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[mirror_ubuntu-bionic-kernel.git] / net / bluetooth / l2cap_core.c
1 /*
2 BlueZ - Bluetooth protocol stack for Linux
3 Copyright (C) 2000-2001 Qualcomm Incorporated
4 Copyright (C) 2009-2010 Gustavo F. Padovan <gustavo@padovan.org>
5 Copyright (C) 2010 Google Inc.
6 Copyright (C) 2011 ProFUSION Embedded Systems
7 Copyright (c) 2012 Code Aurora Forum. All rights reserved.
8
9 Written 2000,2001 by Maxim Krasnyansky <maxk@qualcomm.com>
10
11 This program is free software; you can redistribute it and/or modify
12 it under the terms of the GNU General Public License version 2 as
13 published by the Free Software Foundation;
14
15 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
16 OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS.
18 IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) AND AUTHOR(S) BE LIABLE FOR ANY
19 CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES
20 WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
21 ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
22 OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
23
24 ALL LIABILITY, INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PATENTS,
25 COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS, RELATING TO USE OF THIS
26 SOFTWARE IS DISCLAIMED.
27 */
28
29 /* Bluetooth L2CAP core. */
30
31 #include <linux/module.h>
32
33 #include <linux/debugfs.h>
34 #include <linux/crc16.h>
35 #include <linux/filter.h>
36
37 #include <net/bluetooth/bluetooth.h>
38 #include <net/bluetooth/hci_core.h>
39 #include <net/bluetooth/l2cap.h>
40
41 #include "smp.h"
42 #include "a2mp.h"
43 #include "amp.h"
44
45 #define LE_FLOWCTL_MAX_CREDITS 65535
46
47 bool disable_ertm;
48
49 static u32 l2cap_feat_mask = L2CAP_FEAT_FIXED_CHAN | L2CAP_FEAT_UCD;
50
51 static LIST_HEAD(chan_list);
52 static DEFINE_RWLOCK(chan_list_lock);
53
54 static u16 le_max_credits = L2CAP_LE_MAX_CREDITS;
55 static u16 le_default_mps = L2CAP_LE_DEFAULT_MPS;
56
57 static struct sk_buff *l2cap_build_cmd(struct l2cap_conn *conn,
58 u8 code, u8 ident, u16 dlen, void *data);
59 static void l2cap_send_cmd(struct l2cap_conn *conn, u8 ident, u8 code, u16 len,
60 void *data);
61 static int l2cap_build_conf_req(struct l2cap_chan *chan, void *data, 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 if (olen == sizeof(efs)) {
3367 remote_efs = 1;
3368 memcpy(&efs, (void *) val, olen);
3369 }
3370 break;
3371
3372 case L2CAP_CONF_EWS:
3373 if (!(chan->conn->local_fixed_chan & L2CAP_FC_A2MP))
3374 return -ECONNREFUSED;
3375
3376 set_bit(FLAG_EXT_CTRL, &chan->flags);
3377 set_bit(CONF_EWS_RECV, &chan->conf_state);
3378 chan->tx_win_max = L2CAP_DEFAULT_EXT_WINDOW;
3379 chan->remote_tx_win = val;
3380 break;
3381
3382 default:
3383 if (hint)
3384 break;
3385
3386 result = L2CAP_CONF_UNKNOWN;
3387 *((u8 *) ptr++) = type;
3388 break;
3389 }
3390 }
3391
3392 if (chan->num_conf_rsp || chan->num_conf_req > 1)
3393 goto done;
3394
3395 switch (chan->mode) {
3396 case L2CAP_MODE_STREAMING:
3397 case L2CAP_MODE_ERTM:
3398 if (!test_bit(CONF_STATE2_DEVICE, &chan->conf_state)) {
3399 chan->mode = l2cap_select_mode(rfc.mode,
3400 chan->conn->feat_mask);
3401 break;
3402 }
3403
3404 if (remote_efs) {
3405 if (__l2cap_efs_supported(chan->conn))
3406 set_bit(FLAG_EFS_ENABLE, &chan->flags);
3407 else
3408 return -ECONNREFUSED;
3409 }
3410
3411 if (chan->mode != rfc.mode)
3412 return -ECONNREFUSED;
3413
3414 break;
3415 }
3416
3417 done:
3418 if (chan->mode != rfc.mode) {
3419 result = L2CAP_CONF_UNACCEPT;
3420 rfc.mode = chan->mode;
3421
3422 if (chan->num_conf_rsp == 1)
3423 return -ECONNREFUSED;
3424
3425 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3426 (unsigned long) &rfc, endptr - ptr);
3427 }
3428
3429 if (result == L2CAP_CONF_SUCCESS) {
3430 /* Configure output options and let the other side know
3431 * which ones we don't like. */
3432
3433 if (mtu < L2CAP_DEFAULT_MIN_MTU)
3434 result = L2CAP_CONF_UNACCEPT;
3435 else {
3436 chan->omtu = mtu;
3437 set_bit(CONF_MTU_DONE, &chan->conf_state);
3438 }
3439 l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->omtu, endptr - ptr);
3440
3441 if (remote_efs) {
3442 if (chan->local_stype != L2CAP_SERV_NOTRAFIC &&
3443 efs.stype != L2CAP_SERV_NOTRAFIC &&
3444 efs.stype != chan->local_stype) {
3445
3446 result = L2CAP_CONF_UNACCEPT;
3447
3448 if (chan->num_conf_req >= 1)
3449 return -ECONNREFUSED;
3450
3451 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS,
3452 sizeof(efs),
3453 (unsigned long) &efs, endptr - ptr);
3454 } else {
3455 /* Send PENDING Conf Rsp */
3456 result = L2CAP_CONF_PENDING;
3457 set_bit(CONF_LOC_CONF_PEND, &chan->conf_state);
3458 }
3459 }
3460
3461 switch (rfc.mode) {
3462 case L2CAP_MODE_BASIC:
3463 chan->fcs = L2CAP_FCS_NONE;
3464 set_bit(CONF_MODE_DONE, &chan->conf_state);
3465 break;
3466
3467 case L2CAP_MODE_ERTM:
3468 if (!test_bit(CONF_EWS_RECV, &chan->conf_state))
3469 chan->remote_tx_win = rfc.txwin_size;
3470 else
3471 rfc.txwin_size = L2CAP_DEFAULT_TX_WINDOW;
3472
3473 chan->remote_max_tx = rfc.max_transmit;
3474
3475 size = min_t(u16, le16_to_cpu(rfc.max_pdu_size),
3476 chan->conn->mtu - L2CAP_EXT_HDR_SIZE -
3477 L2CAP_SDULEN_SIZE - L2CAP_FCS_SIZE);
3478 rfc.max_pdu_size = cpu_to_le16(size);
3479 chan->remote_mps = size;
3480
3481 __l2cap_set_ertm_timeouts(chan, &rfc);
3482
3483 set_bit(CONF_MODE_DONE, &chan->conf_state);
3484
3485 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC,
3486 sizeof(rfc), (unsigned long) &rfc, endptr - ptr);
3487
3488 if (test_bit(FLAG_EFS_ENABLE, &chan->flags)) {
3489 chan->remote_id = efs.id;
3490 chan->remote_stype = efs.stype;
3491 chan->remote_msdu = le16_to_cpu(efs.msdu);
3492 chan->remote_flush_to =
3493 le32_to_cpu(efs.flush_to);
3494 chan->remote_acc_lat =
3495 le32_to_cpu(efs.acc_lat);
3496 chan->remote_sdu_itime =
3497 le32_to_cpu(efs.sdu_itime);
3498 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS,
3499 sizeof(efs),
3500 (unsigned long) &efs, endptr - ptr);
3501 }
3502 break;
3503
3504 case L2CAP_MODE_STREAMING:
3505 size = min_t(u16, le16_to_cpu(rfc.max_pdu_size),
3506 chan->conn->mtu - L2CAP_EXT_HDR_SIZE -
3507 L2CAP_SDULEN_SIZE - L2CAP_FCS_SIZE);
3508 rfc.max_pdu_size = cpu_to_le16(size);
3509 chan->remote_mps = size;
3510
3511 set_bit(CONF_MODE_DONE, &chan->conf_state);
3512
3513 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3514 (unsigned long) &rfc, endptr - ptr);
3515
3516 break;
3517
3518 default:
3519 result = L2CAP_CONF_UNACCEPT;
3520
3521 memset(&rfc, 0, sizeof(rfc));
3522 rfc.mode = chan->mode;
3523 }
3524
3525 if (result == L2CAP_CONF_SUCCESS)
3526 set_bit(CONF_OUTPUT_DONE, &chan->conf_state);
3527 }
3528 rsp->scid = cpu_to_le16(chan->dcid);
3529 rsp->result = cpu_to_le16(result);
3530 rsp->flags = cpu_to_le16(0);
3531
3532 return ptr - data;
3533 }
3534
3535 static int l2cap_parse_conf_rsp(struct l2cap_chan *chan, void *rsp, int len,
3536 void *data, size_t size, u16 *result)
3537 {
3538 struct l2cap_conf_req *req = data;
3539 void *ptr = req->data;
3540 void *endptr = data + size;
3541 int type, olen;
3542 unsigned long val;
3543 struct l2cap_conf_rfc rfc = { .mode = L2CAP_MODE_BASIC };
3544 struct l2cap_conf_efs efs;
3545
3546 BT_DBG("chan %p, rsp %p, len %d, req %p", chan, rsp, len, data);
3547
3548 while (len >= L2CAP_CONF_OPT_SIZE) {
3549 len -= l2cap_get_conf_opt(&rsp, &type, &olen, &val);
3550
3551 switch (type) {
3552 case L2CAP_CONF_MTU:
3553 if (val < L2CAP_DEFAULT_MIN_MTU) {
3554 *result = L2CAP_CONF_UNACCEPT;
3555 chan->imtu = L2CAP_DEFAULT_MIN_MTU;
3556 } else
3557 chan->imtu = val;
3558 l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->imtu, endptr - ptr);
3559 break;
3560
3561 case L2CAP_CONF_FLUSH_TO:
3562 chan->flush_to = val;
3563 l2cap_add_conf_opt(&ptr, L2CAP_CONF_FLUSH_TO,
3564 2, chan->flush_to, endptr - ptr);
3565 break;
3566
3567 case L2CAP_CONF_RFC:
3568 if (olen == sizeof(rfc))
3569 memcpy(&rfc, (void *)val, olen);
3570
3571 if (test_bit(CONF_STATE2_DEVICE, &chan->conf_state) &&
3572 rfc.mode != chan->mode)
3573 return -ECONNREFUSED;
3574
3575 chan->fcs = 0;
3576
3577 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC,
3578 sizeof(rfc), (unsigned long) &rfc, endptr - ptr);
3579 break;
3580
3581 case L2CAP_CONF_EWS:
3582 chan->ack_win = min_t(u16, val, chan->ack_win);
3583 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EWS, 2,
3584 chan->tx_win, endptr - ptr);
3585 break;
3586
3587 case L2CAP_CONF_EFS:
3588 if (olen == sizeof(efs)) {
3589 memcpy(&efs, (void *)val, olen);
3590
3591 if (chan->local_stype != L2CAP_SERV_NOTRAFIC &&
3592 efs.stype != L2CAP_SERV_NOTRAFIC &&
3593 efs.stype != chan->local_stype)
3594 return -ECONNREFUSED;
3595
3596 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS, sizeof(efs),
3597 (unsigned long) &efs, endptr - ptr);
3598 }
3599 break;
3600
3601 case L2CAP_CONF_FCS:
3602 if (*result == L2CAP_CONF_PENDING)
3603 if (val == L2CAP_FCS_NONE)
3604 set_bit(CONF_RECV_NO_FCS,
3605 &chan->conf_state);
3606 break;
3607 }
3608 }
3609
3610 if (chan->mode == L2CAP_MODE_BASIC && chan->mode != rfc.mode)
3611 return -ECONNREFUSED;
3612
3613 chan->mode = rfc.mode;
3614
3615 if (*result == L2CAP_CONF_SUCCESS || *result == L2CAP_CONF_PENDING) {
3616 switch (rfc.mode) {
3617 case L2CAP_MODE_ERTM:
3618 chan->retrans_timeout = le16_to_cpu(rfc.retrans_timeout);
3619 chan->monitor_timeout = le16_to_cpu(rfc.monitor_timeout);
3620 chan->mps = le16_to_cpu(rfc.max_pdu_size);
3621 if (!test_bit(FLAG_EXT_CTRL, &chan->flags))
3622 chan->ack_win = min_t(u16, chan->ack_win,
3623 rfc.txwin_size);
3624
3625 if (test_bit(FLAG_EFS_ENABLE, &chan->flags)) {
3626 chan->local_msdu = le16_to_cpu(efs.msdu);
3627 chan->local_sdu_itime =
3628 le32_to_cpu(efs.sdu_itime);
3629 chan->local_acc_lat = le32_to_cpu(efs.acc_lat);
3630 chan->local_flush_to =
3631 le32_to_cpu(efs.flush_to);
3632 }
3633 break;
3634
3635 case L2CAP_MODE_STREAMING:
3636 chan->mps = le16_to_cpu(rfc.max_pdu_size);
3637 }
3638 }
3639
3640 req->dcid = cpu_to_le16(chan->dcid);
3641 req->flags = cpu_to_le16(0);
3642
3643 return ptr - data;
3644 }
3645
3646 static int l2cap_build_conf_rsp(struct l2cap_chan *chan, void *data,
3647 u16 result, u16 flags)
3648 {
3649 struct l2cap_conf_rsp *rsp = data;
3650 void *ptr = rsp->data;
3651
3652 BT_DBG("chan %p", chan);
3653
3654 rsp->scid = cpu_to_le16(chan->dcid);
3655 rsp->result = cpu_to_le16(result);
3656 rsp->flags = cpu_to_le16(flags);
3657
3658 return ptr - data;
3659 }
3660
3661 void __l2cap_le_connect_rsp_defer(struct l2cap_chan *chan)
3662 {
3663 struct l2cap_le_conn_rsp rsp;
3664 struct l2cap_conn *conn = chan->conn;
3665
3666 BT_DBG("chan %p", chan);
3667
3668 rsp.dcid = cpu_to_le16(chan->scid);
3669 rsp.mtu = cpu_to_le16(chan->imtu);
3670 rsp.mps = cpu_to_le16(chan->mps);
3671 rsp.credits = cpu_to_le16(chan->rx_credits);
3672 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
3673
3674 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CONN_RSP, sizeof(rsp),
3675 &rsp);
3676 }
3677
3678 void __l2cap_connect_rsp_defer(struct l2cap_chan *chan)
3679 {
3680 struct l2cap_conn_rsp rsp;
3681 struct l2cap_conn *conn = chan->conn;
3682 u8 buf[128];
3683 u8 rsp_code;
3684
3685 rsp.scid = cpu_to_le16(chan->dcid);
3686 rsp.dcid = cpu_to_le16(chan->scid);
3687 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
3688 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
3689
3690 if (chan->hs_hcon)
3691 rsp_code = L2CAP_CREATE_CHAN_RSP;
3692 else
3693 rsp_code = L2CAP_CONN_RSP;
3694
3695 BT_DBG("chan %p rsp_code %u", chan, rsp_code);
3696
3697 l2cap_send_cmd(conn, chan->ident, rsp_code, sizeof(rsp), &rsp);
3698
3699 if (test_and_set_bit(CONF_REQ_SENT, &chan->conf_state))
3700 return;
3701
3702 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
3703 l2cap_build_conf_req(chan, buf, sizeof(buf)), buf);
3704 chan->num_conf_req++;
3705 }
3706
3707 static void l2cap_conf_rfc_get(struct l2cap_chan *chan, void *rsp, int len)
3708 {
3709 int type, olen;
3710 unsigned long val;
3711 /* Use sane default values in case a misbehaving remote device
3712 * did not send an RFC or extended window size option.
3713 */
3714 u16 txwin_ext = chan->ack_win;
3715 struct l2cap_conf_rfc rfc = {
3716 .mode = chan->mode,
3717 .retrans_timeout = cpu_to_le16(L2CAP_DEFAULT_RETRANS_TO),
3718 .monitor_timeout = cpu_to_le16(L2CAP_DEFAULT_MONITOR_TO),
3719 .max_pdu_size = cpu_to_le16(chan->imtu),
3720 .txwin_size = min_t(u16, chan->ack_win, L2CAP_DEFAULT_TX_WINDOW),
3721 };
3722
3723 BT_DBG("chan %p, rsp %p, len %d", chan, rsp, len);
3724
3725 if ((chan->mode != L2CAP_MODE_ERTM) && (chan->mode != L2CAP_MODE_STREAMING))
3726 return;
3727
3728 while (len >= L2CAP_CONF_OPT_SIZE) {
3729 len -= l2cap_get_conf_opt(&rsp, &type, &olen, &val);
3730
3731 switch (type) {
3732 case L2CAP_CONF_RFC:
3733 if (olen == sizeof(rfc))
3734 memcpy(&rfc, (void *)val, olen);
3735 break;
3736 case L2CAP_CONF_EWS:
3737 txwin_ext = val;
3738 break;
3739 }
3740 }
3741
3742 switch (rfc.mode) {
3743 case L2CAP_MODE_ERTM:
3744 chan->retrans_timeout = le16_to_cpu(rfc.retrans_timeout);
3745 chan->monitor_timeout = le16_to_cpu(rfc.monitor_timeout);
3746 chan->mps = le16_to_cpu(rfc.max_pdu_size);
3747 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
3748 chan->ack_win = min_t(u16, chan->ack_win, txwin_ext);
3749 else
3750 chan->ack_win = min_t(u16, chan->ack_win,
3751 rfc.txwin_size);
3752 break;
3753 case L2CAP_MODE_STREAMING:
3754 chan->mps = le16_to_cpu(rfc.max_pdu_size);
3755 }
3756 }
3757
3758 static inline int l2cap_command_rej(struct l2cap_conn *conn,
3759 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
3760 u8 *data)
3761 {
3762 struct l2cap_cmd_rej_unk *rej = (struct l2cap_cmd_rej_unk *) data;
3763
3764 if (cmd_len < sizeof(*rej))
3765 return -EPROTO;
3766
3767 if (rej->reason != L2CAP_REJ_NOT_UNDERSTOOD)
3768 return 0;
3769
3770 if ((conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT) &&
3771 cmd->ident == conn->info_ident) {
3772 cancel_delayed_work(&conn->info_timer);
3773
3774 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
3775 conn->info_ident = 0;
3776
3777 l2cap_conn_start(conn);
3778 }
3779
3780 return 0;
3781 }
3782
3783 static struct l2cap_chan *l2cap_connect(struct l2cap_conn *conn,
3784 struct l2cap_cmd_hdr *cmd,
3785 u8 *data, u8 rsp_code, u8 amp_id)
3786 {
3787 struct l2cap_conn_req *req = (struct l2cap_conn_req *) data;
3788 struct l2cap_conn_rsp rsp;
3789 struct l2cap_chan *chan = NULL, *pchan;
3790 int result, status = L2CAP_CS_NO_INFO;
3791
3792 u16 dcid = 0, scid = __le16_to_cpu(req->scid);
3793 __le16 psm = req->psm;
3794
3795 BT_DBG("psm 0x%2.2x scid 0x%4.4x", __le16_to_cpu(psm), scid);
3796
3797 /* Check if we have socket listening on psm */
3798 pchan = l2cap_global_chan_by_psm(BT_LISTEN, psm, &conn->hcon->src,
3799 &conn->hcon->dst, ACL_LINK);
3800 if (!pchan) {
3801 result = L2CAP_CR_BAD_PSM;
3802 goto sendresp;
3803 }
3804
3805 mutex_lock(&conn->chan_lock);
3806 l2cap_chan_lock(pchan);
3807
3808 /* Check if the ACL is secure enough (if not SDP) */
3809 if (psm != cpu_to_le16(L2CAP_PSM_SDP) &&
3810 !hci_conn_check_link_mode(conn->hcon)) {
3811 conn->disc_reason = HCI_ERROR_AUTH_FAILURE;
3812 result = L2CAP_CR_SEC_BLOCK;
3813 goto response;
3814 }
3815
3816 result = L2CAP_CR_NO_MEM;
3817
3818 /* Check if we already have channel with that dcid */
3819 if (__l2cap_get_chan_by_dcid(conn, scid))
3820 goto response;
3821
3822 chan = pchan->ops->new_connection(pchan);
3823 if (!chan)
3824 goto response;
3825
3826 /* For certain devices (ex: HID mouse), support for authentication,
3827 * pairing and bonding is optional. For such devices, inorder to avoid
3828 * the ACL alive for too long after L2CAP disconnection, reset the ACL
3829 * disc_timeout back to HCI_DISCONN_TIMEOUT during L2CAP connect.
3830 */
3831 conn->hcon->disc_timeout = HCI_DISCONN_TIMEOUT;
3832
3833 bacpy(&chan->src, &conn->hcon->src);
3834 bacpy(&chan->dst, &conn->hcon->dst);
3835 chan->src_type = bdaddr_src_type(conn->hcon);
3836 chan->dst_type = bdaddr_dst_type(conn->hcon);
3837 chan->psm = psm;
3838 chan->dcid = scid;
3839 chan->local_amp_id = amp_id;
3840
3841 __l2cap_chan_add(conn, chan);
3842
3843 dcid = chan->scid;
3844
3845 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
3846
3847 chan->ident = cmd->ident;
3848
3849 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE) {
3850 if (l2cap_chan_check_security(chan, false)) {
3851 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
3852 l2cap_state_change(chan, BT_CONNECT2);
3853 result = L2CAP_CR_PEND;
3854 status = L2CAP_CS_AUTHOR_PEND;
3855 chan->ops->defer(chan);
3856 } else {
3857 /* Force pending result for AMP controllers.
3858 * The connection will succeed after the
3859 * physical link is up.
3860 */
3861 if (amp_id == AMP_ID_BREDR) {
3862 l2cap_state_change(chan, BT_CONFIG);
3863 result = L2CAP_CR_SUCCESS;
3864 } else {
3865 l2cap_state_change(chan, BT_CONNECT2);
3866 result = L2CAP_CR_PEND;
3867 }
3868 status = L2CAP_CS_NO_INFO;
3869 }
3870 } else {
3871 l2cap_state_change(chan, BT_CONNECT2);
3872 result = L2CAP_CR_PEND;
3873 status = L2CAP_CS_AUTHEN_PEND;
3874 }
3875 } else {
3876 l2cap_state_change(chan, BT_CONNECT2);
3877 result = L2CAP_CR_PEND;
3878 status = L2CAP_CS_NO_INFO;
3879 }
3880
3881 response:
3882 l2cap_chan_unlock(pchan);
3883 mutex_unlock(&conn->chan_lock);
3884 l2cap_chan_put(pchan);
3885
3886 sendresp:
3887 rsp.scid = cpu_to_le16(scid);
3888 rsp.dcid = cpu_to_le16(dcid);
3889 rsp.result = cpu_to_le16(result);
3890 rsp.status = cpu_to_le16(status);
3891 l2cap_send_cmd(conn, cmd->ident, rsp_code, sizeof(rsp), &rsp);
3892
3893 if (result == L2CAP_CR_PEND && status == L2CAP_CS_NO_INFO) {
3894 struct l2cap_info_req info;
3895 info.type = cpu_to_le16(L2CAP_IT_FEAT_MASK);
3896
3897 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_SENT;
3898 conn->info_ident = l2cap_get_ident(conn);
3899
3900 schedule_delayed_work(&conn->info_timer, L2CAP_INFO_TIMEOUT);
3901
3902 l2cap_send_cmd(conn, conn->info_ident, L2CAP_INFO_REQ,
3903 sizeof(info), &info);
3904 }
3905
3906 if (chan && !test_bit(CONF_REQ_SENT, &chan->conf_state) &&
3907 result == L2CAP_CR_SUCCESS) {
3908 u8 buf[128];
3909 set_bit(CONF_REQ_SENT, &chan->conf_state);
3910 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
3911 l2cap_build_conf_req(chan, buf, sizeof(buf)), buf);
3912 chan->num_conf_req++;
3913 }
3914
3915 return chan;
3916 }
3917
3918 static int l2cap_connect_req(struct l2cap_conn *conn,
3919 struct l2cap_cmd_hdr *cmd, u16 cmd_len, u8 *data)
3920 {
3921 struct hci_dev *hdev = conn->hcon->hdev;
3922 struct hci_conn *hcon = conn->hcon;
3923
3924 if (cmd_len < sizeof(struct l2cap_conn_req))
3925 return -EPROTO;
3926
3927 hci_dev_lock(hdev);
3928 if (hci_dev_test_flag(hdev, HCI_MGMT) &&
3929 !test_and_set_bit(HCI_CONN_MGMT_CONNECTED, &hcon->flags))
3930 mgmt_device_connected(hdev, hcon, 0, NULL, 0);
3931 hci_dev_unlock(hdev);
3932
3933 l2cap_connect(conn, cmd, data, L2CAP_CONN_RSP, 0);
3934 return 0;
3935 }
3936
3937 static int l2cap_connect_create_rsp(struct l2cap_conn *conn,
3938 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
3939 u8 *data)
3940 {
3941 struct l2cap_conn_rsp *rsp = (struct l2cap_conn_rsp *) data;
3942 u16 scid, dcid, result, status;
3943 struct l2cap_chan *chan;
3944 u8 req[128];
3945 int err;
3946
3947 if (cmd_len < sizeof(*rsp))
3948 return -EPROTO;
3949
3950 scid = __le16_to_cpu(rsp->scid);
3951 dcid = __le16_to_cpu(rsp->dcid);
3952 result = __le16_to_cpu(rsp->result);
3953 status = __le16_to_cpu(rsp->status);
3954
3955 BT_DBG("dcid 0x%4.4x scid 0x%4.4x result 0x%2.2x status 0x%2.2x",
3956 dcid, scid, result, status);
3957
3958 mutex_lock(&conn->chan_lock);
3959
3960 if (scid) {
3961 chan = __l2cap_get_chan_by_scid(conn, scid);
3962 if (!chan) {
3963 err = -EBADSLT;
3964 goto unlock;
3965 }
3966 } else {
3967 chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
3968 if (!chan) {
3969 err = -EBADSLT;
3970 goto unlock;
3971 }
3972 }
3973
3974 err = 0;
3975
3976 l2cap_chan_lock(chan);
3977
3978 switch (result) {
3979 case L2CAP_CR_SUCCESS:
3980 l2cap_state_change(chan, BT_CONFIG);
3981 chan->ident = 0;
3982 chan->dcid = dcid;
3983 clear_bit(CONF_CONNECT_PEND, &chan->conf_state);
3984
3985 if (test_and_set_bit(CONF_REQ_SENT, &chan->conf_state))
3986 break;
3987
3988 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
3989 l2cap_build_conf_req(chan, req, sizeof(req)), req);
3990 chan->num_conf_req++;
3991 break;
3992
3993 case L2CAP_CR_PEND:
3994 set_bit(CONF_CONNECT_PEND, &chan->conf_state);
3995 break;
3996
3997 default:
3998 l2cap_chan_del(chan, ECONNREFUSED);
3999 break;
4000 }
4001
4002 l2cap_chan_unlock(chan);
4003
4004 unlock:
4005 mutex_unlock(&conn->chan_lock);
4006
4007 return err;
4008 }
4009
4010 static inline void set_default_fcs(struct l2cap_chan *chan)
4011 {
4012 /* FCS is enabled only in ERTM or streaming mode, if one or both
4013 * sides request it.
4014 */
4015 if (chan->mode != L2CAP_MODE_ERTM && chan->mode != L2CAP_MODE_STREAMING)
4016 chan->fcs = L2CAP_FCS_NONE;
4017 else if (!test_bit(CONF_RECV_NO_FCS, &chan->conf_state))
4018 chan->fcs = L2CAP_FCS_CRC16;
4019 }
4020
4021 static void l2cap_send_efs_conf_rsp(struct l2cap_chan *chan, void *data,
4022 u8 ident, u16 flags)
4023 {
4024 struct l2cap_conn *conn = chan->conn;
4025
4026 BT_DBG("conn %p chan %p ident %d flags 0x%4.4x", conn, chan, ident,
4027 flags);
4028
4029 clear_bit(CONF_LOC_CONF_PEND, &chan->conf_state);
4030 set_bit(CONF_OUTPUT_DONE, &chan->conf_state);
4031
4032 l2cap_send_cmd(conn, ident, L2CAP_CONF_RSP,
4033 l2cap_build_conf_rsp(chan, data,
4034 L2CAP_CONF_SUCCESS, flags), data);
4035 }
4036
4037 static void cmd_reject_invalid_cid(struct l2cap_conn *conn, u8 ident,
4038 u16 scid, u16 dcid)
4039 {
4040 struct l2cap_cmd_rej_cid rej;
4041
4042 rej.reason = cpu_to_le16(L2CAP_REJ_INVALID_CID);
4043 rej.scid = __cpu_to_le16(scid);
4044 rej.dcid = __cpu_to_le16(dcid);
4045
4046 l2cap_send_cmd(conn, ident, L2CAP_COMMAND_REJ, sizeof(rej), &rej);
4047 }
4048
4049 static inline int l2cap_config_req(struct l2cap_conn *conn,
4050 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4051 u8 *data)
4052 {
4053 struct l2cap_conf_req *req = (struct l2cap_conf_req *) data;
4054 u16 dcid, flags;
4055 u8 rsp[64];
4056 struct l2cap_chan *chan;
4057 int len, err = 0;
4058
4059 if (cmd_len < sizeof(*req))
4060 return -EPROTO;
4061
4062 dcid = __le16_to_cpu(req->dcid);
4063 flags = __le16_to_cpu(req->flags);
4064
4065 BT_DBG("dcid 0x%4.4x flags 0x%2.2x", dcid, flags);
4066
4067 chan = l2cap_get_chan_by_scid(conn, dcid);
4068 if (!chan) {
4069 cmd_reject_invalid_cid(conn, cmd->ident, dcid, 0);
4070 return 0;
4071 }
4072
4073 if (chan->state != BT_CONFIG && chan->state != BT_CONNECT2) {
4074 cmd_reject_invalid_cid(conn, cmd->ident, chan->scid,
4075 chan->dcid);
4076 goto unlock;
4077 }
4078
4079 /* Reject if config buffer is too small. */
4080 len = cmd_len - sizeof(*req);
4081 if (chan->conf_len + len > sizeof(chan->conf_req)) {
4082 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP,
4083 l2cap_build_conf_rsp(chan, rsp,
4084 L2CAP_CONF_REJECT, flags), rsp);
4085 goto unlock;
4086 }
4087
4088 /* Store config. */
4089 memcpy(chan->conf_req + chan->conf_len, req->data, len);
4090 chan->conf_len += len;
4091
4092 if (flags & L2CAP_CONF_FLAG_CONTINUATION) {
4093 /* Incomplete config. Send empty response. */
4094 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP,
4095 l2cap_build_conf_rsp(chan, rsp,
4096 L2CAP_CONF_SUCCESS, flags), rsp);
4097 goto unlock;
4098 }
4099
4100 /* Complete config. */
4101 len = l2cap_parse_conf_req(chan, rsp, sizeof(rsp));
4102 if (len < 0) {
4103 l2cap_send_disconn_req(chan, ECONNRESET);
4104 goto unlock;
4105 }
4106
4107 chan->ident = cmd->ident;
4108 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP, len, rsp);
4109 chan->num_conf_rsp++;
4110
4111 /* Reset config buffer. */
4112 chan->conf_len = 0;
4113
4114 if (!test_bit(CONF_OUTPUT_DONE, &chan->conf_state))
4115 goto unlock;
4116
4117 if (test_bit(CONF_INPUT_DONE, &chan->conf_state)) {
4118 set_default_fcs(chan);
4119
4120 if (chan->mode == L2CAP_MODE_ERTM ||
4121 chan->mode == L2CAP_MODE_STREAMING)
4122 err = l2cap_ertm_init(chan);
4123
4124 if (err < 0)
4125 l2cap_send_disconn_req(chan, -err);
4126 else
4127 l2cap_chan_ready(chan);
4128
4129 goto unlock;
4130 }
4131
4132 if (!test_and_set_bit(CONF_REQ_SENT, &chan->conf_state)) {
4133 u8 buf[64];
4134 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
4135 l2cap_build_conf_req(chan, buf, sizeof(buf)), buf);
4136 chan->num_conf_req++;
4137 }
4138
4139 /* Got Conf Rsp PENDING from remote side and assume we sent
4140 Conf Rsp PENDING in the code above */
4141 if (test_bit(CONF_REM_CONF_PEND, &chan->conf_state) &&
4142 test_bit(CONF_LOC_CONF_PEND, &chan->conf_state)) {
4143
4144 /* check compatibility */
4145
4146 /* Send rsp for BR/EDR channel */
4147 if (!chan->hs_hcon)
4148 l2cap_send_efs_conf_rsp(chan, rsp, cmd->ident, flags);
4149 else
4150 chan->ident = cmd->ident;
4151 }
4152
4153 unlock:
4154 l2cap_chan_unlock(chan);
4155 return err;
4156 }
4157
4158 static inline int l2cap_config_rsp(struct l2cap_conn *conn,
4159 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4160 u8 *data)
4161 {
4162 struct l2cap_conf_rsp *rsp = (struct l2cap_conf_rsp *)data;
4163 u16 scid, flags, result;
4164 struct l2cap_chan *chan;
4165 int len = cmd_len - sizeof(*rsp);
4166 int err = 0;
4167
4168 if (cmd_len < sizeof(*rsp))
4169 return -EPROTO;
4170
4171 scid = __le16_to_cpu(rsp->scid);
4172 flags = __le16_to_cpu(rsp->flags);
4173 result = __le16_to_cpu(rsp->result);
4174
4175 BT_DBG("scid 0x%4.4x flags 0x%2.2x result 0x%2.2x len %d", scid, flags,
4176 result, len);
4177
4178 chan = l2cap_get_chan_by_scid(conn, scid);
4179 if (!chan)
4180 return 0;
4181
4182 switch (result) {
4183 case L2CAP_CONF_SUCCESS:
4184 l2cap_conf_rfc_get(chan, rsp->data, len);
4185 clear_bit(CONF_REM_CONF_PEND, &chan->conf_state);
4186 break;
4187
4188 case L2CAP_CONF_PENDING:
4189 set_bit(CONF_REM_CONF_PEND, &chan->conf_state);
4190
4191 if (test_bit(CONF_LOC_CONF_PEND, &chan->conf_state)) {
4192 char buf[64];
4193
4194 len = l2cap_parse_conf_rsp(chan, rsp->data, len,
4195 buf, sizeof(buf), &result);
4196 if (len < 0) {
4197 l2cap_send_disconn_req(chan, ECONNRESET);
4198 goto done;
4199 }
4200
4201 if (!chan->hs_hcon) {
4202 l2cap_send_efs_conf_rsp(chan, buf, cmd->ident,
4203 0);
4204 } else {
4205 if (l2cap_check_efs(chan)) {
4206 amp_create_logical_link(chan);
4207 chan->ident = cmd->ident;
4208 }
4209 }
4210 }
4211 goto done;
4212
4213 case L2CAP_CONF_UNACCEPT:
4214 if (chan->num_conf_rsp <= L2CAP_CONF_MAX_CONF_RSP) {
4215 char req[64];
4216
4217 if (len > sizeof(req) - sizeof(struct l2cap_conf_req)) {
4218 l2cap_send_disconn_req(chan, ECONNRESET);
4219 goto done;
4220 }
4221
4222 /* throw out any old stored conf requests */
4223 result = L2CAP_CONF_SUCCESS;
4224 len = l2cap_parse_conf_rsp(chan, rsp->data, len,
4225 req, sizeof(req), &result);
4226 if (len < 0) {
4227 l2cap_send_disconn_req(chan, ECONNRESET);
4228 goto done;
4229 }
4230
4231 l2cap_send_cmd(conn, l2cap_get_ident(conn),
4232 L2CAP_CONF_REQ, len, req);
4233 chan->num_conf_req++;
4234 if (result != L2CAP_CONF_SUCCESS)
4235 goto done;
4236 break;
4237 }
4238
4239 default:
4240 l2cap_chan_set_err(chan, ECONNRESET);
4241
4242 __set_chan_timer(chan, L2CAP_DISC_REJ_TIMEOUT);
4243 l2cap_send_disconn_req(chan, ECONNRESET);
4244 goto done;
4245 }
4246
4247 if (flags & L2CAP_CONF_FLAG_CONTINUATION)
4248 goto done;
4249
4250 set_bit(CONF_INPUT_DONE, &chan->conf_state);
4251
4252 if (test_bit(CONF_OUTPUT_DONE, &chan->conf_state)) {
4253 set_default_fcs(chan);
4254
4255 if (chan->mode == L2CAP_MODE_ERTM ||
4256 chan->mode == L2CAP_MODE_STREAMING)
4257 err = l2cap_ertm_init(chan);
4258
4259 if (err < 0)
4260 l2cap_send_disconn_req(chan, -err);
4261 else
4262 l2cap_chan_ready(chan);
4263 }
4264
4265 done:
4266 l2cap_chan_unlock(chan);
4267 return err;
4268 }
4269
4270 static inline int l2cap_disconnect_req(struct l2cap_conn *conn,
4271 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4272 u8 *data)
4273 {
4274 struct l2cap_disconn_req *req = (struct l2cap_disconn_req *) data;
4275 struct l2cap_disconn_rsp rsp;
4276 u16 dcid, scid;
4277 struct l2cap_chan *chan;
4278
4279 if (cmd_len != sizeof(*req))
4280 return -EPROTO;
4281
4282 scid = __le16_to_cpu(req->scid);
4283 dcid = __le16_to_cpu(req->dcid);
4284
4285 BT_DBG("scid 0x%4.4x dcid 0x%4.4x", scid, dcid);
4286
4287 mutex_lock(&conn->chan_lock);
4288
4289 chan = __l2cap_get_chan_by_scid(conn, dcid);
4290 if (!chan) {
4291 mutex_unlock(&conn->chan_lock);
4292 cmd_reject_invalid_cid(conn, cmd->ident, dcid, scid);
4293 return 0;
4294 }
4295
4296 l2cap_chan_lock(chan);
4297
4298 rsp.dcid = cpu_to_le16(chan->scid);
4299 rsp.scid = cpu_to_le16(chan->dcid);
4300 l2cap_send_cmd(conn, cmd->ident, L2CAP_DISCONN_RSP, sizeof(rsp), &rsp);
4301
4302 chan->ops->set_shutdown(chan);
4303
4304 l2cap_chan_hold(chan);
4305 l2cap_chan_del(chan, ECONNRESET);
4306
4307 l2cap_chan_unlock(chan);
4308
4309 chan->ops->close(chan);
4310 l2cap_chan_put(chan);
4311
4312 mutex_unlock(&conn->chan_lock);
4313
4314 return 0;
4315 }
4316
4317 static inline int l2cap_disconnect_rsp(struct l2cap_conn *conn,
4318 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4319 u8 *data)
4320 {
4321 struct l2cap_disconn_rsp *rsp = (struct l2cap_disconn_rsp *) data;
4322 u16 dcid, scid;
4323 struct l2cap_chan *chan;
4324
4325 if (cmd_len != sizeof(*rsp))
4326 return -EPROTO;
4327
4328 scid = __le16_to_cpu(rsp->scid);
4329 dcid = __le16_to_cpu(rsp->dcid);
4330
4331 BT_DBG("dcid 0x%4.4x scid 0x%4.4x", dcid, scid);
4332
4333 mutex_lock(&conn->chan_lock);
4334
4335 chan = __l2cap_get_chan_by_scid(conn, scid);
4336 if (!chan) {
4337 mutex_unlock(&conn->chan_lock);
4338 return 0;
4339 }
4340
4341 l2cap_chan_lock(chan);
4342
4343 l2cap_chan_hold(chan);
4344 l2cap_chan_del(chan, 0);
4345
4346 l2cap_chan_unlock(chan);
4347
4348 chan->ops->close(chan);
4349 l2cap_chan_put(chan);
4350
4351 mutex_unlock(&conn->chan_lock);
4352
4353 return 0;
4354 }
4355
4356 static inline int l2cap_information_req(struct l2cap_conn *conn,
4357 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4358 u8 *data)
4359 {
4360 struct l2cap_info_req *req = (struct l2cap_info_req *) data;
4361 u16 type;
4362
4363 if (cmd_len != sizeof(*req))
4364 return -EPROTO;
4365
4366 type = __le16_to_cpu(req->type);
4367
4368 BT_DBG("type 0x%4.4x", type);
4369
4370 if (type == L2CAP_IT_FEAT_MASK) {
4371 u8 buf[8];
4372 u32 feat_mask = l2cap_feat_mask;
4373 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) buf;
4374 rsp->type = cpu_to_le16(L2CAP_IT_FEAT_MASK);
4375 rsp->result = cpu_to_le16(L2CAP_IR_SUCCESS);
4376 if (!disable_ertm)
4377 feat_mask |= L2CAP_FEAT_ERTM | L2CAP_FEAT_STREAMING
4378 | L2CAP_FEAT_FCS;
4379 if (conn->local_fixed_chan & L2CAP_FC_A2MP)
4380 feat_mask |= L2CAP_FEAT_EXT_FLOW
4381 | L2CAP_FEAT_EXT_WINDOW;
4382
4383 put_unaligned_le32(feat_mask, rsp->data);
4384 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(buf),
4385 buf);
4386 } else if (type == L2CAP_IT_FIXED_CHAN) {
4387 u8 buf[12];
4388 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) buf;
4389
4390 rsp->type = cpu_to_le16(L2CAP_IT_FIXED_CHAN);
4391 rsp->result = cpu_to_le16(L2CAP_IR_SUCCESS);
4392 rsp->data[0] = conn->local_fixed_chan;
4393 memset(rsp->data + 1, 0, 7);
4394 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(buf),
4395 buf);
4396 } else {
4397 struct l2cap_info_rsp rsp;
4398 rsp.type = cpu_to_le16(type);
4399 rsp.result = cpu_to_le16(L2CAP_IR_NOTSUPP);
4400 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(rsp),
4401 &rsp);
4402 }
4403
4404 return 0;
4405 }
4406
4407 static inline int l2cap_information_rsp(struct l2cap_conn *conn,
4408 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4409 u8 *data)
4410 {
4411 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) data;
4412 u16 type, result;
4413
4414 if (cmd_len < sizeof(*rsp))
4415 return -EPROTO;
4416
4417 type = __le16_to_cpu(rsp->type);
4418 result = __le16_to_cpu(rsp->result);
4419
4420 BT_DBG("type 0x%4.4x result 0x%2.2x", type, result);
4421
4422 /* L2CAP Info req/rsp are unbound to channels, add extra checks */
4423 if (cmd->ident != conn->info_ident ||
4424 conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE)
4425 return 0;
4426
4427 cancel_delayed_work(&conn->info_timer);
4428
4429 if (result != L2CAP_IR_SUCCESS) {
4430 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4431 conn->info_ident = 0;
4432
4433 l2cap_conn_start(conn);
4434
4435 return 0;
4436 }
4437
4438 switch (type) {
4439 case L2CAP_IT_FEAT_MASK:
4440 conn->feat_mask = get_unaligned_le32(rsp->data);
4441
4442 if (conn->feat_mask & L2CAP_FEAT_FIXED_CHAN) {
4443 struct l2cap_info_req req;
4444 req.type = cpu_to_le16(L2CAP_IT_FIXED_CHAN);
4445
4446 conn->info_ident = l2cap_get_ident(conn);
4447
4448 l2cap_send_cmd(conn, conn->info_ident,
4449 L2CAP_INFO_REQ, sizeof(req), &req);
4450 } else {
4451 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4452 conn->info_ident = 0;
4453
4454 l2cap_conn_start(conn);
4455 }
4456 break;
4457
4458 case L2CAP_IT_FIXED_CHAN:
4459 conn->remote_fixed_chan = rsp->data[0];
4460 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4461 conn->info_ident = 0;
4462
4463 l2cap_conn_start(conn);
4464 break;
4465 }
4466
4467 return 0;
4468 }
4469
4470 static int l2cap_create_channel_req(struct l2cap_conn *conn,
4471 struct l2cap_cmd_hdr *cmd,
4472 u16 cmd_len, void *data)
4473 {
4474 struct l2cap_create_chan_req *req = data;
4475 struct l2cap_create_chan_rsp rsp;
4476 struct l2cap_chan *chan;
4477 struct hci_dev *hdev;
4478 u16 psm, scid;
4479
4480 if (cmd_len != sizeof(*req))
4481 return -EPROTO;
4482
4483 if (!(conn->local_fixed_chan & L2CAP_FC_A2MP))
4484 return -EINVAL;
4485
4486 psm = le16_to_cpu(req->psm);
4487 scid = le16_to_cpu(req->scid);
4488
4489 BT_DBG("psm 0x%2.2x, scid 0x%4.4x, amp_id %d", psm, scid, req->amp_id);
4490
4491 /* For controller id 0 make BR/EDR connection */
4492 if (req->amp_id == AMP_ID_BREDR) {
4493 l2cap_connect(conn, cmd, data, L2CAP_CREATE_CHAN_RSP,
4494 req->amp_id);
4495 return 0;
4496 }
4497
4498 /* Validate AMP controller id */
4499 hdev = hci_dev_get(req->amp_id);
4500 if (!hdev)
4501 goto error;
4502
4503 if (hdev->dev_type != HCI_AMP || !test_bit(HCI_UP, &hdev->flags)) {
4504 hci_dev_put(hdev);
4505 goto error;
4506 }
4507
4508 chan = l2cap_connect(conn, cmd, data, L2CAP_CREATE_CHAN_RSP,
4509 req->amp_id);
4510 if (chan) {
4511 struct amp_mgr *mgr = conn->hcon->amp_mgr;
4512 struct hci_conn *hs_hcon;
4513
4514 hs_hcon = hci_conn_hash_lookup_ba(hdev, AMP_LINK,
4515 &conn->hcon->dst);
4516 if (!hs_hcon) {
4517 hci_dev_put(hdev);
4518 cmd_reject_invalid_cid(conn, cmd->ident, chan->scid,
4519 chan->dcid);
4520 return 0;
4521 }
4522
4523 BT_DBG("mgr %p bredr_chan %p hs_hcon %p", mgr, chan, hs_hcon);
4524
4525 mgr->bredr_chan = chan;
4526 chan->hs_hcon = hs_hcon;
4527 chan->fcs = L2CAP_FCS_NONE;
4528 conn->mtu = hdev->block_mtu;
4529 }
4530
4531 hci_dev_put(hdev);
4532
4533 return 0;
4534
4535 error:
4536 rsp.dcid = 0;
4537 rsp.scid = cpu_to_le16(scid);
4538 rsp.result = cpu_to_le16(L2CAP_CR_BAD_AMP);
4539 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
4540
4541 l2cap_send_cmd(conn, cmd->ident, L2CAP_CREATE_CHAN_RSP,
4542 sizeof(rsp), &rsp);
4543
4544 return 0;
4545 }
4546
4547 static void l2cap_send_move_chan_req(struct l2cap_chan *chan, u8 dest_amp_id)
4548 {
4549 struct l2cap_move_chan_req req;
4550 u8 ident;
4551
4552 BT_DBG("chan %p, dest_amp_id %d", chan, dest_amp_id);
4553
4554 ident = l2cap_get_ident(chan->conn);
4555 chan->ident = ident;
4556
4557 req.icid = cpu_to_le16(chan->scid);
4558 req.dest_amp_id = dest_amp_id;
4559
4560 l2cap_send_cmd(chan->conn, ident, L2CAP_MOVE_CHAN_REQ, sizeof(req),
4561 &req);
4562
4563 __set_chan_timer(chan, L2CAP_MOVE_TIMEOUT);
4564 }
4565
4566 static void l2cap_send_move_chan_rsp(struct l2cap_chan *chan, u16 result)
4567 {
4568 struct l2cap_move_chan_rsp rsp;
4569
4570 BT_DBG("chan %p, result 0x%4.4x", chan, result);
4571
4572 rsp.icid = cpu_to_le16(chan->dcid);
4573 rsp.result = cpu_to_le16(result);
4574
4575 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_MOVE_CHAN_RSP,
4576 sizeof(rsp), &rsp);
4577 }
4578
4579 static void l2cap_send_move_chan_cfm(struct l2cap_chan *chan, u16 result)
4580 {
4581 struct l2cap_move_chan_cfm cfm;
4582
4583 BT_DBG("chan %p, result 0x%4.4x", chan, result);
4584
4585 chan->ident = l2cap_get_ident(chan->conn);
4586
4587 cfm.icid = cpu_to_le16(chan->scid);
4588 cfm.result = cpu_to_le16(result);
4589
4590 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_MOVE_CHAN_CFM,
4591 sizeof(cfm), &cfm);
4592
4593 __set_chan_timer(chan, L2CAP_MOVE_TIMEOUT);
4594 }
4595
4596 static void l2cap_send_move_chan_cfm_icid(struct l2cap_conn *conn, u16 icid)
4597 {
4598 struct l2cap_move_chan_cfm cfm;
4599
4600 BT_DBG("conn %p, icid 0x%4.4x", conn, icid);
4601
4602 cfm.icid = cpu_to_le16(icid);
4603 cfm.result = cpu_to_le16(L2CAP_MC_UNCONFIRMED);
4604
4605 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_MOVE_CHAN_CFM,
4606 sizeof(cfm), &cfm);
4607 }
4608
4609 static void l2cap_send_move_chan_cfm_rsp(struct l2cap_conn *conn, u8 ident,
4610 u16 icid)
4611 {
4612 struct l2cap_move_chan_cfm_rsp rsp;
4613
4614 BT_DBG("icid 0x%4.4x", icid);
4615
4616 rsp.icid = cpu_to_le16(icid);
4617 l2cap_send_cmd(conn, ident, L2CAP_MOVE_CHAN_CFM_RSP, sizeof(rsp), &rsp);
4618 }
4619
4620 static void __release_logical_link(struct l2cap_chan *chan)
4621 {
4622 chan->hs_hchan = NULL;
4623 chan->hs_hcon = NULL;
4624
4625 /* Placeholder - release the logical link */
4626 }
4627
4628 static void l2cap_logical_fail(struct l2cap_chan *chan)
4629 {
4630 /* Logical link setup failed */
4631 if (chan->state != BT_CONNECTED) {
4632 /* Create channel failure, disconnect */
4633 l2cap_send_disconn_req(chan, ECONNRESET);
4634 return;
4635 }
4636
4637 switch (chan->move_role) {
4638 case L2CAP_MOVE_ROLE_RESPONDER:
4639 l2cap_move_done(chan);
4640 l2cap_send_move_chan_rsp(chan, L2CAP_MR_NOT_SUPP);
4641 break;
4642 case L2CAP_MOVE_ROLE_INITIATOR:
4643 if (chan->move_state == L2CAP_MOVE_WAIT_LOGICAL_COMP ||
4644 chan->move_state == L2CAP_MOVE_WAIT_LOGICAL_CFM) {
4645 /* Remote has only sent pending or
4646 * success responses, clean up
4647 */
4648 l2cap_move_done(chan);
4649 }
4650
4651 /* Other amp move states imply that the move
4652 * has already aborted
4653 */
4654 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
4655 break;
4656 }
4657 }
4658
4659 static void l2cap_logical_finish_create(struct l2cap_chan *chan,
4660 struct hci_chan *hchan)
4661 {
4662 struct l2cap_conf_rsp rsp;
4663
4664 chan->hs_hchan = hchan;
4665 chan->hs_hcon->l2cap_data = chan->conn;
4666
4667 l2cap_send_efs_conf_rsp(chan, &rsp, chan->ident, 0);
4668
4669 if (test_bit(CONF_INPUT_DONE, &chan->conf_state)) {
4670 int err;
4671
4672 set_default_fcs(chan);
4673
4674 err = l2cap_ertm_init(chan);
4675 if (err < 0)
4676 l2cap_send_disconn_req(chan, -err);
4677 else
4678 l2cap_chan_ready(chan);
4679 }
4680 }
4681
4682 static void l2cap_logical_finish_move(struct l2cap_chan *chan,
4683 struct hci_chan *hchan)
4684 {
4685 chan->hs_hcon = hchan->conn;
4686 chan->hs_hcon->l2cap_data = chan->conn;
4687
4688 BT_DBG("move_state %d", chan->move_state);
4689
4690 switch (chan->move_state) {
4691 case L2CAP_MOVE_WAIT_LOGICAL_COMP:
4692 /* Move confirm will be sent after a success
4693 * response is received
4694 */
4695 chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
4696 break;
4697 case L2CAP_MOVE_WAIT_LOGICAL_CFM:
4698 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
4699 chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
4700 } else if (chan->move_role == L2CAP_MOVE_ROLE_INITIATOR) {
4701 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM_RSP;
4702 l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
4703 } else if (chan->move_role == L2CAP_MOVE_ROLE_RESPONDER) {
4704 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
4705 l2cap_send_move_chan_rsp(chan, L2CAP_MR_SUCCESS);
4706 }
4707 break;
4708 default:
4709 /* Move was not in expected state, free the channel */
4710 __release_logical_link(chan);
4711
4712 chan->move_state = L2CAP_MOVE_STABLE;
4713 }
4714 }
4715
4716 /* Call with chan locked */
4717 void l2cap_logical_cfm(struct l2cap_chan *chan, struct hci_chan *hchan,
4718 u8 status)
4719 {
4720 BT_DBG("chan %p, hchan %p, status %d", chan, hchan, status);
4721
4722 if (status) {
4723 l2cap_logical_fail(chan);
4724 __release_logical_link(chan);
4725 return;
4726 }
4727
4728 if (chan->state != BT_CONNECTED) {
4729 /* Ignore logical link if channel is on BR/EDR */
4730 if (chan->local_amp_id != AMP_ID_BREDR)
4731 l2cap_logical_finish_create(chan, hchan);
4732 } else {
4733 l2cap_logical_finish_move(chan, hchan);
4734 }
4735 }
4736
4737 void l2cap_move_start(struct l2cap_chan *chan)
4738 {
4739 BT_DBG("chan %p", chan);
4740
4741 if (chan->local_amp_id == AMP_ID_BREDR) {
4742 if (chan->chan_policy != BT_CHANNEL_POLICY_AMP_PREFERRED)
4743 return;
4744 chan->move_role = L2CAP_MOVE_ROLE_INITIATOR;
4745 chan->move_state = L2CAP_MOVE_WAIT_PREPARE;
4746 /* Placeholder - start physical link setup */
4747 } else {
4748 chan->move_role = L2CAP_MOVE_ROLE_INITIATOR;
4749 chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
4750 chan->move_id = 0;
4751 l2cap_move_setup(chan);
4752 l2cap_send_move_chan_req(chan, 0);
4753 }
4754 }
4755
4756 static void l2cap_do_create(struct l2cap_chan *chan, int result,
4757 u8 local_amp_id, u8 remote_amp_id)
4758 {
4759 BT_DBG("chan %p state %s %u -> %u", chan, state_to_string(chan->state),
4760 local_amp_id, remote_amp_id);
4761
4762 chan->fcs = L2CAP_FCS_NONE;
4763
4764 /* Outgoing channel on AMP */
4765 if (chan->state == BT_CONNECT) {
4766 if (result == L2CAP_CR_SUCCESS) {
4767 chan->local_amp_id = local_amp_id;
4768 l2cap_send_create_chan_req(chan, remote_amp_id);
4769 } else {
4770 /* Revert to BR/EDR connect */
4771 l2cap_send_conn_req(chan);
4772 }
4773
4774 return;
4775 }
4776
4777 /* Incoming channel on AMP */
4778 if (__l2cap_no_conn_pending(chan)) {
4779 struct l2cap_conn_rsp rsp;
4780 char buf[128];
4781 rsp.scid = cpu_to_le16(chan->dcid);
4782 rsp.dcid = cpu_to_le16(chan->scid);
4783
4784 if (result == L2CAP_CR_SUCCESS) {
4785 /* Send successful response */
4786 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
4787 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
4788 } else {
4789 /* Send negative response */
4790 rsp.result = cpu_to_le16(L2CAP_CR_NO_MEM);
4791 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
4792 }
4793
4794 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_CREATE_CHAN_RSP,
4795 sizeof(rsp), &rsp);
4796
4797 if (result == L2CAP_CR_SUCCESS) {
4798 l2cap_state_change(chan, BT_CONFIG);
4799 set_bit(CONF_REQ_SENT, &chan->conf_state);
4800 l2cap_send_cmd(chan->conn, l2cap_get_ident(chan->conn),
4801 L2CAP_CONF_REQ,
4802 l2cap_build_conf_req(chan, buf, sizeof(buf)), buf);
4803 chan->num_conf_req++;
4804 }
4805 }
4806 }
4807
4808 static void l2cap_do_move_initiate(struct l2cap_chan *chan, u8 local_amp_id,
4809 u8 remote_amp_id)
4810 {
4811 l2cap_move_setup(chan);
4812 chan->move_id = local_amp_id;
4813 chan->move_state = L2CAP_MOVE_WAIT_RSP;
4814
4815 l2cap_send_move_chan_req(chan, remote_amp_id);
4816 }
4817
4818 static void l2cap_do_move_respond(struct l2cap_chan *chan, int result)
4819 {
4820 struct hci_chan *hchan = NULL;
4821
4822 /* Placeholder - get hci_chan for logical link */
4823
4824 if (hchan) {
4825 if (hchan->state == BT_CONNECTED) {
4826 /* Logical link is ready to go */
4827 chan->hs_hcon = hchan->conn;
4828 chan->hs_hcon->l2cap_data = chan->conn;
4829 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
4830 l2cap_send_move_chan_rsp(chan, L2CAP_MR_SUCCESS);
4831
4832 l2cap_logical_cfm(chan, hchan, L2CAP_MR_SUCCESS);
4833 } else {
4834 /* Wait for logical link to be ready */
4835 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
4836 }
4837 } else {
4838 /* Logical link not available */
4839 l2cap_send_move_chan_rsp(chan, L2CAP_MR_NOT_ALLOWED);
4840 }
4841 }
4842
4843 static void l2cap_do_move_cancel(struct l2cap_chan *chan, int result)
4844 {
4845 if (chan->move_role == L2CAP_MOVE_ROLE_RESPONDER) {
4846 u8 rsp_result;
4847 if (result == -EINVAL)
4848 rsp_result = L2CAP_MR_BAD_ID;
4849 else
4850 rsp_result = L2CAP_MR_NOT_ALLOWED;
4851
4852 l2cap_send_move_chan_rsp(chan, rsp_result);
4853 }
4854
4855 chan->move_role = L2CAP_MOVE_ROLE_NONE;
4856 chan->move_state = L2CAP_MOVE_STABLE;
4857
4858 /* Restart data transmission */
4859 l2cap_ertm_send(chan);
4860 }
4861
4862 /* Invoke with locked chan */
4863 void __l2cap_physical_cfm(struct l2cap_chan *chan, int result)
4864 {
4865 u8 local_amp_id = chan->local_amp_id;
4866 u8 remote_amp_id = chan->remote_amp_id;
4867
4868 BT_DBG("chan %p, result %d, local_amp_id %d, remote_amp_id %d",
4869 chan, result, local_amp_id, remote_amp_id);
4870
4871 if (chan->state == BT_DISCONN || chan->state == BT_CLOSED) {
4872 l2cap_chan_unlock(chan);
4873 return;
4874 }
4875
4876 if (chan->state != BT_CONNECTED) {
4877 l2cap_do_create(chan, result, local_amp_id, remote_amp_id);
4878 } else if (result != L2CAP_MR_SUCCESS) {
4879 l2cap_do_move_cancel(chan, result);
4880 } else {
4881 switch (chan->move_role) {
4882 case L2CAP_MOVE_ROLE_INITIATOR:
4883 l2cap_do_move_initiate(chan, local_amp_id,
4884 remote_amp_id);
4885 break;
4886 case L2CAP_MOVE_ROLE_RESPONDER:
4887 l2cap_do_move_respond(chan, result);
4888 break;
4889 default:
4890 l2cap_do_move_cancel(chan, result);
4891 break;
4892 }
4893 }
4894 }
4895
4896 static inline int l2cap_move_channel_req(struct l2cap_conn *conn,
4897 struct l2cap_cmd_hdr *cmd,
4898 u16 cmd_len, void *data)
4899 {
4900 struct l2cap_move_chan_req *req = data;
4901 struct l2cap_move_chan_rsp rsp;
4902 struct l2cap_chan *chan;
4903 u16 icid = 0;
4904 u16 result = L2CAP_MR_NOT_ALLOWED;
4905
4906 if (cmd_len != sizeof(*req))
4907 return -EPROTO;
4908
4909 icid = le16_to_cpu(req->icid);
4910
4911 BT_DBG("icid 0x%4.4x, dest_amp_id %d", icid, req->dest_amp_id);
4912
4913 if (!(conn->local_fixed_chan & L2CAP_FC_A2MP))
4914 return -EINVAL;
4915
4916 chan = l2cap_get_chan_by_dcid(conn, icid);
4917 if (!chan) {
4918 rsp.icid = cpu_to_le16(icid);
4919 rsp.result = cpu_to_le16(L2CAP_MR_NOT_ALLOWED);
4920 l2cap_send_cmd(conn, cmd->ident, L2CAP_MOVE_CHAN_RSP,
4921 sizeof(rsp), &rsp);
4922 return 0;
4923 }
4924
4925 chan->ident = cmd->ident;
4926
4927 if (chan->scid < L2CAP_CID_DYN_START ||
4928 chan->chan_policy == BT_CHANNEL_POLICY_BREDR_ONLY ||
4929 (chan->mode != L2CAP_MODE_ERTM &&
4930 chan->mode != L2CAP_MODE_STREAMING)) {
4931 result = L2CAP_MR_NOT_ALLOWED;
4932 goto send_move_response;
4933 }
4934
4935 if (chan->local_amp_id == req->dest_amp_id) {
4936 result = L2CAP_MR_SAME_ID;
4937 goto send_move_response;
4938 }
4939
4940 if (req->dest_amp_id != AMP_ID_BREDR) {
4941 struct hci_dev *hdev;
4942 hdev = hci_dev_get(req->dest_amp_id);
4943 if (!hdev || hdev->dev_type != HCI_AMP ||
4944 !test_bit(HCI_UP, &hdev->flags)) {
4945 if (hdev)
4946 hci_dev_put(hdev);
4947
4948 result = L2CAP_MR_BAD_ID;
4949 goto send_move_response;
4950 }
4951 hci_dev_put(hdev);
4952 }
4953
4954 /* Detect a move collision. Only send a collision response
4955 * if this side has "lost", otherwise proceed with the move.
4956 * The winner has the larger bd_addr.
4957 */
4958 if ((__chan_is_moving(chan) ||
4959 chan->move_role != L2CAP_MOVE_ROLE_NONE) &&
4960 bacmp(&conn->hcon->src, &conn->hcon->dst) > 0) {
4961 result = L2CAP_MR_COLLISION;
4962 goto send_move_response;
4963 }
4964
4965 chan->move_role = L2CAP_MOVE_ROLE_RESPONDER;
4966 l2cap_move_setup(chan);
4967 chan->move_id = req->dest_amp_id;
4968 icid = chan->dcid;
4969
4970 if (req->dest_amp_id == AMP_ID_BREDR) {
4971 /* Moving to BR/EDR */
4972 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
4973 chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
4974 result = L2CAP_MR_PEND;
4975 } else {
4976 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
4977 result = L2CAP_MR_SUCCESS;
4978 }
4979 } else {
4980 chan->move_state = L2CAP_MOVE_WAIT_PREPARE;
4981 /* Placeholder - uncomment when amp functions are available */
4982 /*amp_accept_physical(chan, req->dest_amp_id);*/
4983 result = L2CAP_MR_PEND;
4984 }
4985
4986 send_move_response:
4987 l2cap_send_move_chan_rsp(chan, result);
4988
4989 l2cap_chan_unlock(chan);
4990
4991 return 0;
4992 }
4993
4994 static void l2cap_move_continue(struct l2cap_conn *conn, u16 icid, u16 result)
4995 {
4996 struct l2cap_chan *chan;
4997 struct hci_chan *hchan = NULL;
4998
4999 chan = l2cap_get_chan_by_scid(conn, icid);
5000 if (!chan) {
5001 l2cap_send_move_chan_cfm_icid(conn, icid);
5002 return;
5003 }
5004
5005 __clear_chan_timer(chan);
5006 if (result == L2CAP_MR_PEND)
5007 __set_chan_timer(chan, L2CAP_MOVE_ERTX_TIMEOUT);
5008
5009 switch (chan->move_state) {
5010 case L2CAP_MOVE_WAIT_LOGICAL_COMP:
5011 /* Move confirm will be sent when logical link
5012 * is complete.
5013 */
5014 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
5015 break;
5016 case L2CAP_MOVE_WAIT_RSP_SUCCESS:
5017 if (result == L2CAP_MR_PEND) {
5018 break;
5019 } else if (test_bit(CONN_LOCAL_BUSY,
5020 &chan->conn_state)) {
5021 chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
5022 } else {
5023 /* Logical link is up or moving to BR/EDR,
5024 * proceed with move
5025 */
5026 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM_RSP;
5027 l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
5028 }
5029 break;
5030 case L2CAP_MOVE_WAIT_RSP:
5031 /* Moving to AMP */
5032 if (result == L2CAP_MR_SUCCESS) {
5033 /* Remote is ready, send confirm immediately
5034 * after logical link is ready
5035 */
5036 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
5037 } else {
5038 /* Both logical link and move success
5039 * are required to confirm
5040 */
5041 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_COMP;
5042 }
5043
5044 /* Placeholder - get hci_chan for logical link */
5045 if (!hchan) {
5046 /* Logical link not available */
5047 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5048 break;
5049 }
5050
5051 /* If the logical link is not yet connected, do not
5052 * send confirmation.
5053 */
5054 if (hchan->state != BT_CONNECTED)
5055 break;
5056
5057 /* Logical link is already ready to go */
5058
5059 chan->hs_hcon = hchan->conn;
5060 chan->hs_hcon->l2cap_data = chan->conn;
5061
5062 if (result == L2CAP_MR_SUCCESS) {
5063 /* Can confirm now */
5064 l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
5065 } else {
5066 /* Now only need move success
5067 * to confirm
5068 */
5069 chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
5070 }
5071
5072 l2cap_logical_cfm(chan, hchan, L2CAP_MR_SUCCESS);
5073 break;
5074 default:
5075 /* Any other amp move state means the move failed. */
5076 chan->move_id = chan->local_amp_id;
5077 l2cap_move_done(chan);
5078 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5079 }
5080
5081 l2cap_chan_unlock(chan);
5082 }
5083
5084 static void l2cap_move_fail(struct l2cap_conn *conn, u8 ident, u16 icid,
5085 u16 result)
5086 {
5087 struct l2cap_chan *chan;
5088
5089 chan = l2cap_get_chan_by_ident(conn, ident);
5090 if (!chan) {
5091 /* Could not locate channel, icid is best guess */
5092 l2cap_send_move_chan_cfm_icid(conn, icid);
5093 return;
5094 }
5095
5096 __clear_chan_timer(chan);
5097
5098 if (chan->move_role == L2CAP_MOVE_ROLE_INITIATOR) {
5099 if (result == L2CAP_MR_COLLISION) {
5100 chan->move_role = L2CAP_MOVE_ROLE_RESPONDER;
5101 } else {
5102 /* Cleanup - cancel move */
5103 chan->move_id = chan->local_amp_id;
5104 l2cap_move_done(chan);
5105 }
5106 }
5107
5108 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5109
5110 l2cap_chan_unlock(chan);
5111 }
5112
5113 static int l2cap_move_channel_rsp(struct l2cap_conn *conn,
5114 struct l2cap_cmd_hdr *cmd,
5115 u16 cmd_len, void *data)
5116 {
5117 struct l2cap_move_chan_rsp *rsp = data;
5118 u16 icid, result;
5119
5120 if (cmd_len != sizeof(*rsp))
5121 return -EPROTO;
5122
5123 icid = le16_to_cpu(rsp->icid);
5124 result = le16_to_cpu(rsp->result);
5125
5126 BT_DBG("icid 0x%4.4x, result 0x%4.4x", icid, result);
5127
5128 if (result == L2CAP_MR_SUCCESS || result == L2CAP_MR_PEND)
5129 l2cap_move_continue(conn, icid, result);
5130 else
5131 l2cap_move_fail(conn, cmd->ident, icid, result);
5132
5133 return 0;
5134 }
5135
5136 static int l2cap_move_channel_confirm(struct l2cap_conn *conn,
5137 struct l2cap_cmd_hdr *cmd,
5138 u16 cmd_len, void *data)
5139 {
5140 struct l2cap_move_chan_cfm *cfm = data;
5141 struct l2cap_chan *chan;
5142 u16 icid, result;
5143
5144 if (cmd_len != sizeof(*cfm))
5145 return -EPROTO;
5146
5147 icid = le16_to_cpu(cfm->icid);
5148 result = le16_to_cpu(cfm->result);
5149
5150 BT_DBG("icid 0x%4.4x, result 0x%4.4x", icid, result);
5151
5152 chan = l2cap_get_chan_by_dcid(conn, icid);
5153 if (!chan) {
5154 /* Spec requires a response even if the icid was not found */
5155 l2cap_send_move_chan_cfm_rsp(conn, cmd->ident, icid);
5156 return 0;
5157 }
5158
5159 if (chan->move_state == L2CAP_MOVE_WAIT_CONFIRM) {
5160 if (result == L2CAP_MC_CONFIRMED) {
5161 chan->local_amp_id = chan->move_id;
5162 if (chan->local_amp_id == AMP_ID_BREDR)
5163 __release_logical_link(chan);
5164 } else {
5165 chan->move_id = chan->local_amp_id;
5166 }
5167
5168 l2cap_move_done(chan);
5169 }
5170
5171 l2cap_send_move_chan_cfm_rsp(conn, cmd->ident, icid);
5172
5173 l2cap_chan_unlock(chan);
5174
5175 return 0;
5176 }
5177
5178 static inline int l2cap_move_channel_confirm_rsp(struct l2cap_conn *conn,
5179 struct l2cap_cmd_hdr *cmd,
5180 u16 cmd_len, void *data)
5181 {
5182 struct l2cap_move_chan_cfm_rsp *rsp = data;
5183 struct l2cap_chan *chan;
5184 u16 icid;
5185
5186 if (cmd_len != sizeof(*rsp))
5187 return -EPROTO;
5188
5189 icid = le16_to_cpu(rsp->icid);
5190
5191 BT_DBG("icid 0x%4.4x", icid);
5192
5193 chan = l2cap_get_chan_by_scid(conn, icid);
5194 if (!chan)
5195 return 0;
5196
5197 __clear_chan_timer(chan);
5198
5199 if (chan->move_state == L2CAP_MOVE_WAIT_CONFIRM_RSP) {
5200 chan->local_amp_id = chan->move_id;
5201
5202 if (chan->local_amp_id == AMP_ID_BREDR && chan->hs_hchan)
5203 __release_logical_link(chan);
5204
5205 l2cap_move_done(chan);
5206 }
5207
5208 l2cap_chan_unlock(chan);
5209
5210 return 0;
5211 }
5212
5213 static inline int l2cap_conn_param_update_req(struct l2cap_conn *conn,
5214 struct l2cap_cmd_hdr *cmd,
5215 u16 cmd_len, u8 *data)
5216 {
5217 struct hci_conn *hcon = conn->hcon;
5218 struct l2cap_conn_param_update_req *req;
5219 struct l2cap_conn_param_update_rsp rsp;
5220 u16 min, max, latency, to_multiplier;
5221 int err;
5222
5223 if (hcon->role != HCI_ROLE_MASTER)
5224 return -EINVAL;
5225
5226 if (cmd_len != sizeof(struct l2cap_conn_param_update_req))
5227 return -EPROTO;
5228
5229 req = (struct l2cap_conn_param_update_req *) data;
5230 min = __le16_to_cpu(req->min);
5231 max = __le16_to_cpu(req->max);
5232 latency = __le16_to_cpu(req->latency);
5233 to_multiplier = __le16_to_cpu(req->to_multiplier);
5234
5235 BT_DBG("min 0x%4.4x max 0x%4.4x latency: 0x%4.4x Timeout: 0x%4.4x",
5236 min, max, latency, to_multiplier);
5237
5238 memset(&rsp, 0, sizeof(rsp));
5239
5240 err = hci_check_conn_params(min, max, latency, to_multiplier);
5241 if (err)
5242 rsp.result = cpu_to_le16(L2CAP_CONN_PARAM_REJECTED);
5243 else
5244 rsp.result = cpu_to_le16(L2CAP_CONN_PARAM_ACCEPTED);
5245
5246 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONN_PARAM_UPDATE_RSP,
5247 sizeof(rsp), &rsp);
5248
5249 if (!err) {
5250 u8 store_hint;
5251
5252 store_hint = hci_le_conn_update(hcon, min, max, latency,
5253 to_multiplier);
5254 mgmt_new_conn_param(hcon->hdev, &hcon->dst, hcon->dst_type,
5255 store_hint, min, max, latency,
5256 to_multiplier);
5257
5258 }
5259
5260 return 0;
5261 }
5262
5263 static int l2cap_le_connect_rsp(struct l2cap_conn *conn,
5264 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5265 u8 *data)
5266 {
5267 struct l2cap_le_conn_rsp *rsp = (struct l2cap_le_conn_rsp *) data;
5268 struct hci_conn *hcon = conn->hcon;
5269 u16 dcid, mtu, mps, credits, result;
5270 struct l2cap_chan *chan;
5271 int err, sec_level;
5272
5273 if (cmd_len < sizeof(*rsp))
5274 return -EPROTO;
5275
5276 dcid = __le16_to_cpu(rsp->dcid);
5277 mtu = __le16_to_cpu(rsp->mtu);
5278 mps = __le16_to_cpu(rsp->mps);
5279 credits = __le16_to_cpu(rsp->credits);
5280 result = __le16_to_cpu(rsp->result);
5281
5282 if (result == L2CAP_CR_SUCCESS && (mtu < 23 || mps < 23 ||
5283 dcid < L2CAP_CID_DYN_START ||
5284 dcid > L2CAP_CID_LE_DYN_END))
5285 return -EPROTO;
5286
5287 BT_DBG("dcid 0x%4.4x mtu %u mps %u credits %u result 0x%2.2x",
5288 dcid, mtu, mps, credits, result);
5289
5290 mutex_lock(&conn->chan_lock);
5291
5292 chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
5293 if (!chan) {
5294 err = -EBADSLT;
5295 goto unlock;
5296 }
5297
5298 err = 0;
5299
5300 l2cap_chan_lock(chan);
5301
5302 switch (result) {
5303 case L2CAP_CR_SUCCESS:
5304 if (__l2cap_get_chan_by_dcid(conn, dcid)) {
5305 err = -EBADSLT;
5306 break;
5307 }
5308
5309 chan->ident = 0;
5310 chan->dcid = dcid;
5311 chan->omtu = mtu;
5312 chan->remote_mps = mps;
5313 chan->tx_credits = credits;
5314 l2cap_chan_ready(chan);
5315 break;
5316
5317 case L2CAP_CR_AUTHENTICATION:
5318 case L2CAP_CR_ENCRYPTION:
5319 /* If we already have MITM protection we can't do
5320 * anything.
5321 */
5322 if (hcon->sec_level > BT_SECURITY_MEDIUM) {
5323 l2cap_chan_del(chan, ECONNREFUSED);
5324 break;
5325 }
5326
5327 sec_level = hcon->sec_level + 1;
5328 if (chan->sec_level < sec_level)
5329 chan->sec_level = sec_level;
5330
5331 /* We'll need to send a new Connect Request */
5332 clear_bit(FLAG_LE_CONN_REQ_SENT, &chan->flags);
5333
5334 smp_conn_security(hcon, chan->sec_level);
5335 break;
5336
5337 default:
5338 l2cap_chan_del(chan, ECONNREFUSED);
5339 break;
5340 }
5341
5342 l2cap_chan_unlock(chan);
5343
5344 unlock:
5345 mutex_unlock(&conn->chan_lock);
5346
5347 return err;
5348 }
5349
5350 static inline int l2cap_bredr_sig_cmd(struct l2cap_conn *conn,
5351 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5352 u8 *data)
5353 {
5354 int err = 0;
5355
5356 switch (cmd->code) {
5357 case L2CAP_COMMAND_REJ:
5358 l2cap_command_rej(conn, cmd, cmd_len, data);
5359 break;
5360
5361 case L2CAP_CONN_REQ:
5362 err = l2cap_connect_req(conn, cmd, cmd_len, data);
5363 break;
5364
5365 case L2CAP_CONN_RSP:
5366 case L2CAP_CREATE_CHAN_RSP:
5367 l2cap_connect_create_rsp(conn, cmd, cmd_len, data);
5368 break;
5369
5370 case L2CAP_CONF_REQ:
5371 err = l2cap_config_req(conn, cmd, cmd_len, data);
5372 break;
5373
5374 case L2CAP_CONF_RSP:
5375 l2cap_config_rsp(conn, cmd, cmd_len, data);
5376 break;
5377
5378 case L2CAP_DISCONN_REQ:
5379 err = l2cap_disconnect_req(conn, cmd, cmd_len, data);
5380 break;
5381
5382 case L2CAP_DISCONN_RSP:
5383 l2cap_disconnect_rsp(conn, cmd, cmd_len, data);
5384 break;
5385
5386 case L2CAP_ECHO_REQ:
5387 l2cap_send_cmd(conn, cmd->ident, L2CAP_ECHO_RSP, cmd_len, data);
5388 break;
5389
5390 case L2CAP_ECHO_RSP:
5391 break;
5392
5393 case L2CAP_INFO_REQ:
5394 err = l2cap_information_req(conn, cmd, cmd_len, data);
5395 break;
5396
5397 case L2CAP_INFO_RSP:
5398 l2cap_information_rsp(conn, cmd, cmd_len, data);
5399 break;
5400
5401 case L2CAP_CREATE_CHAN_REQ:
5402 err = l2cap_create_channel_req(conn, cmd, cmd_len, data);
5403 break;
5404
5405 case L2CAP_MOVE_CHAN_REQ:
5406 err = l2cap_move_channel_req(conn, cmd, cmd_len, data);
5407 break;
5408
5409 case L2CAP_MOVE_CHAN_RSP:
5410 l2cap_move_channel_rsp(conn, cmd, cmd_len, data);
5411 break;
5412
5413 case L2CAP_MOVE_CHAN_CFM:
5414 err = l2cap_move_channel_confirm(conn, cmd, cmd_len, data);
5415 break;
5416
5417 case L2CAP_MOVE_CHAN_CFM_RSP:
5418 l2cap_move_channel_confirm_rsp(conn, cmd, cmd_len, data);
5419 break;
5420
5421 default:
5422 BT_ERR("Unknown BR/EDR signaling command 0x%2.2x", cmd->code);
5423 err = -EINVAL;
5424 break;
5425 }
5426
5427 return err;
5428 }
5429
5430 static int l2cap_le_connect_req(struct l2cap_conn *conn,
5431 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5432 u8 *data)
5433 {
5434 struct l2cap_le_conn_req *req = (struct l2cap_le_conn_req *) data;
5435 struct l2cap_le_conn_rsp rsp;
5436 struct l2cap_chan *chan, *pchan;
5437 u16 dcid, scid, credits, mtu, mps;
5438 __le16 psm;
5439 u8 result;
5440
5441 if (cmd_len != sizeof(*req))
5442 return -EPROTO;
5443
5444 scid = __le16_to_cpu(req->scid);
5445 mtu = __le16_to_cpu(req->mtu);
5446 mps = __le16_to_cpu(req->mps);
5447 psm = req->psm;
5448 dcid = 0;
5449 credits = 0;
5450
5451 if (mtu < 23 || mps < 23)
5452 return -EPROTO;
5453
5454 BT_DBG("psm 0x%2.2x scid 0x%4.4x mtu %u mps %u", __le16_to_cpu(psm),
5455 scid, mtu, mps);
5456
5457 /* Check if we have socket listening on psm */
5458 pchan = l2cap_global_chan_by_psm(BT_LISTEN, psm, &conn->hcon->src,
5459 &conn->hcon->dst, LE_LINK);
5460 if (!pchan) {
5461 result = L2CAP_CR_BAD_PSM;
5462 chan = NULL;
5463 goto response;
5464 }
5465
5466 mutex_lock(&conn->chan_lock);
5467 l2cap_chan_lock(pchan);
5468
5469 if (!smp_sufficient_security(conn->hcon, pchan->sec_level,
5470 SMP_ALLOW_STK)) {
5471 result = L2CAP_CR_AUTHENTICATION;
5472 chan = NULL;
5473 goto response_unlock;
5474 }
5475
5476 /* Check for valid dynamic CID range */
5477 if (scid < L2CAP_CID_DYN_START || scid > L2CAP_CID_LE_DYN_END) {
5478 result = L2CAP_CR_INVALID_SCID;
5479 chan = NULL;
5480 goto response_unlock;
5481 }
5482
5483 /* Check if we already have channel with that dcid */
5484 if (__l2cap_get_chan_by_dcid(conn, scid)) {
5485 result = L2CAP_CR_SCID_IN_USE;
5486 chan = NULL;
5487 goto response_unlock;
5488 }
5489
5490 chan = pchan->ops->new_connection(pchan);
5491 if (!chan) {
5492 result = L2CAP_CR_NO_MEM;
5493 goto response_unlock;
5494 }
5495
5496 l2cap_le_flowctl_init(chan);
5497
5498 bacpy(&chan->src, &conn->hcon->src);
5499 bacpy(&chan->dst, &conn->hcon->dst);
5500 chan->src_type = bdaddr_src_type(conn->hcon);
5501 chan->dst_type = bdaddr_dst_type(conn->hcon);
5502 chan->psm = psm;
5503 chan->dcid = scid;
5504 chan->omtu = mtu;
5505 chan->remote_mps = mps;
5506 chan->tx_credits = __le16_to_cpu(req->credits);
5507
5508 __l2cap_chan_add(conn, chan);
5509 dcid = chan->scid;
5510 credits = chan->rx_credits;
5511
5512 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
5513
5514 chan->ident = cmd->ident;
5515
5516 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
5517 l2cap_state_change(chan, BT_CONNECT2);
5518 /* The following result value is actually not defined
5519 * for LE CoC but we use it to let the function know
5520 * that it should bail out after doing its cleanup
5521 * instead of sending a response.
5522 */
5523 result = L2CAP_CR_PEND;
5524 chan->ops->defer(chan);
5525 } else {
5526 l2cap_chan_ready(chan);
5527 result = L2CAP_CR_SUCCESS;
5528 }
5529
5530 response_unlock:
5531 l2cap_chan_unlock(pchan);
5532 mutex_unlock(&conn->chan_lock);
5533 l2cap_chan_put(pchan);
5534
5535 if (result == L2CAP_CR_PEND)
5536 return 0;
5537
5538 response:
5539 if (chan) {
5540 rsp.mtu = cpu_to_le16(chan->imtu);
5541 rsp.mps = cpu_to_le16(chan->mps);
5542 } else {
5543 rsp.mtu = 0;
5544 rsp.mps = 0;
5545 }
5546
5547 rsp.dcid = cpu_to_le16(dcid);
5548 rsp.credits = cpu_to_le16(credits);
5549 rsp.result = cpu_to_le16(result);
5550
5551 l2cap_send_cmd(conn, cmd->ident, L2CAP_LE_CONN_RSP, sizeof(rsp), &rsp);
5552
5553 return 0;
5554 }
5555
5556 static inline int l2cap_le_credits(struct l2cap_conn *conn,
5557 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5558 u8 *data)
5559 {
5560 struct l2cap_le_credits *pkt;
5561 struct l2cap_chan *chan;
5562 u16 cid, credits, max_credits;
5563
5564 if (cmd_len != sizeof(*pkt))
5565 return -EPROTO;
5566
5567 pkt = (struct l2cap_le_credits *) data;
5568 cid = __le16_to_cpu(pkt->cid);
5569 credits = __le16_to_cpu(pkt->credits);
5570
5571 BT_DBG("cid 0x%4.4x credits 0x%4.4x", cid, credits);
5572
5573 chan = l2cap_get_chan_by_dcid(conn, cid);
5574 if (!chan)
5575 return -EBADSLT;
5576
5577 max_credits = LE_FLOWCTL_MAX_CREDITS - chan->tx_credits;
5578 if (credits > max_credits) {
5579 BT_ERR("LE credits overflow");
5580 l2cap_send_disconn_req(chan, ECONNRESET);
5581 l2cap_chan_unlock(chan);
5582
5583 /* Return 0 so that we don't trigger an unnecessary
5584 * command reject packet.
5585 */
5586 return 0;
5587 }
5588
5589 chan->tx_credits += credits;
5590
5591 /* Resume sending */
5592 l2cap_le_flowctl_send(chan);
5593
5594 if (chan->tx_credits)
5595 chan->ops->resume(chan);
5596
5597 l2cap_chan_unlock(chan);
5598
5599 return 0;
5600 }
5601
5602 static inline int l2cap_le_command_rej(struct l2cap_conn *conn,
5603 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5604 u8 *data)
5605 {
5606 struct l2cap_cmd_rej_unk *rej = (struct l2cap_cmd_rej_unk *) data;
5607 struct l2cap_chan *chan;
5608
5609 if (cmd_len < sizeof(*rej))
5610 return -EPROTO;
5611
5612 mutex_lock(&conn->chan_lock);
5613
5614 chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
5615 if (!chan)
5616 goto done;
5617
5618 l2cap_chan_lock(chan);
5619 l2cap_chan_del(chan, ECONNREFUSED);
5620 l2cap_chan_unlock(chan);
5621
5622 done:
5623 mutex_unlock(&conn->chan_lock);
5624 return 0;
5625 }
5626
5627 static inline int l2cap_le_sig_cmd(struct l2cap_conn *conn,
5628 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5629 u8 *data)
5630 {
5631 int err = 0;
5632
5633 switch (cmd->code) {
5634 case L2CAP_COMMAND_REJ:
5635 l2cap_le_command_rej(conn, cmd, cmd_len, data);
5636 break;
5637
5638 case L2CAP_CONN_PARAM_UPDATE_REQ:
5639 err = l2cap_conn_param_update_req(conn, cmd, cmd_len, data);
5640 break;
5641
5642 case L2CAP_CONN_PARAM_UPDATE_RSP:
5643 break;
5644
5645 case L2CAP_LE_CONN_RSP:
5646 l2cap_le_connect_rsp(conn, cmd, cmd_len, data);
5647 break;
5648
5649 case L2CAP_LE_CONN_REQ:
5650 err = l2cap_le_connect_req(conn, cmd, cmd_len, data);
5651 break;
5652
5653 case L2CAP_LE_CREDITS:
5654 err = l2cap_le_credits(conn, cmd, cmd_len, data);
5655 break;
5656
5657 case L2CAP_DISCONN_REQ:
5658 err = l2cap_disconnect_req(conn, cmd, cmd_len, data);
5659 break;
5660
5661 case L2CAP_DISCONN_RSP:
5662 l2cap_disconnect_rsp(conn, cmd, cmd_len, data);
5663 break;
5664
5665 default:
5666 BT_ERR("Unknown LE signaling command 0x%2.2x", cmd->code);
5667 err = -EINVAL;
5668 break;
5669 }
5670
5671 return err;
5672 }
5673
5674 static inline void l2cap_le_sig_channel(struct l2cap_conn *conn,
5675 struct sk_buff *skb)
5676 {
5677 struct hci_conn *hcon = conn->hcon;
5678 struct l2cap_cmd_hdr *cmd;
5679 u16 len;
5680 int err;
5681
5682 if (hcon->type != LE_LINK)
5683 goto drop;
5684
5685 if (skb->len < L2CAP_CMD_HDR_SIZE)
5686 goto drop;
5687
5688 cmd = (void *) skb->data;
5689 skb_pull(skb, L2CAP_CMD_HDR_SIZE);
5690
5691 len = le16_to_cpu(cmd->len);
5692
5693 BT_DBG("code 0x%2.2x len %d id 0x%2.2x", cmd->code, len, cmd->ident);
5694
5695 if (len != skb->len || !cmd->ident) {
5696 BT_DBG("corrupted command");
5697 goto drop;
5698 }
5699
5700 err = l2cap_le_sig_cmd(conn, cmd, len, skb->data);
5701 if (err) {
5702 struct l2cap_cmd_rej_unk rej;
5703
5704 BT_ERR("Wrong link type (%d)", err);
5705
5706 rej.reason = cpu_to_le16(L2CAP_REJ_NOT_UNDERSTOOD);
5707 l2cap_send_cmd(conn, cmd->ident, L2CAP_COMMAND_REJ,
5708 sizeof(rej), &rej);
5709 }
5710
5711 drop:
5712 kfree_skb(skb);
5713 }
5714
5715 static inline void l2cap_sig_channel(struct l2cap_conn *conn,
5716 struct sk_buff *skb)
5717 {
5718 struct hci_conn *hcon = conn->hcon;
5719 u8 *data = skb->data;
5720 int len = skb->len;
5721 struct l2cap_cmd_hdr cmd;
5722 int err;
5723
5724 l2cap_raw_recv(conn, skb);
5725
5726 if (hcon->type != ACL_LINK)
5727 goto drop;
5728
5729 while (len >= L2CAP_CMD_HDR_SIZE) {
5730 u16 cmd_len;
5731 memcpy(&cmd, data, L2CAP_CMD_HDR_SIZE);
5732 data += L2CAP_CMD_HDR_SIZE;
5733 len -= L2CAP_CMD_HDR_SIZE;
5734
5735 cmd_len = le16_to_cpu(cmd.len);
5736
5737 BT_DBG("code 0x%2.2x len %d id 0x%2.2x", cmd.code, cmd_len,
5738 cmd.ident);
5739
5740 if (cmd_len > len || !cmd.ident) {
5741 BT_DBG("corrupted command");
5742 break;
5743 }
5744
5745 err = l2cap_bredr_sig_cmd(conn, &cmd, cmd_len, data);
5746 if (err) {
5747 struct l2cap_cmd_rej_unk rej;
5748
5749 BT_ERR("Wrong link type (%d)", err);
5750
5751 rej.reason = cpu_to_le16(L2CAP_REJ_NOT_UNDERSTOOD);
5752 l2cap_send_cmd(conn, cmd.ident, L2CAP_COMMAND_REJ,
5753 sizeof(rej), &rej);
5754 }
5755
5756 data += cmd_len;
5757 len -= cmd_len;
5758 }
5759
5760 drop:
5761 kfree_skb(skb);
5762 }
5763
5764 static int l2cap_check_fcs(struct l2cap_chan *chan, struct sk_buff *skb)
5765 {
5766 u16 our_fcs, rcv_fcs;
5767 int hdr_size;
5768
5769 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
5770 hdr_size = L2CAP_EXT_HDR_SIZE;
5771 else
5772 hdr_size = L2CAP_ENH_HDR_SIZE;
5773
5774 if (chan->fcs == L2CAP_FCS_CRC16) {
5775 skb_trim(skb, skb->len - L2CAP_FCS_SIZE);
5776 rcv_fcs = get_unaligned_le16(skb->data + skb->len);
5777 our_fcs = crc16(0, skb->data - hdr_size, skb->len + hdr_size);
5778
5779 if (our_fcs != rcv_fcs)
5780 return -EBADMSG;
5781 }
5782 return 0;
5783 }
5784
5785 static void l2cap_send_i_or_rr_or_rnr(struct l2cap_chan *chan)
5786 {
5787 struct l2cap_ctrl control;
5788
5789 BT_DBG("chan %p", chan);
5790
5791 memset(&control, 0, sizeof(control));
5792 control.sframe = 1;
5793 control.final = 1;
5794 control.reqseq = chan->buffer_seq;
5795 set_bit(CONN_SEND_FBIT, &chan->conn_state);
5796
5797 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
5798 control.super = L2CAP_SUPER_RNR;
5799 l2cap_send_sframe(chan, &control);
5800 }
5801
5802 if (test_and_clear_bit(CONN_REMOTE_BUSY, &chan->conn_state) &&
5803 chan->unacked_frames > 0)
5804 __set_retrans_timer(chan);
5805
5806 /* Send pending iframes */
5807 l2cap_ertm_send(chan);
5808
5809 if (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state) &&
5810 test_bit(CONN_SEND_FBIT, &chan->conn_state)) {
5811 /* F-bit wasn't sent in an s-frame or i-frame yet, so
5812 * send it now.
5813 */
5814 control.super = L2CAP_SUPER_RR;
5815 l2cap_send_sframe(chan, &control);
5816 }
5817 }
5818
5819 static void append_skb_frag(struct sk_buff *skb, struct sk_buff *new_frag,
5820 struct sk_buff **last_frag)
5821 {
5822 /* skb->len reflects data in skb as well as all fragments
5823 * skb->data_len reflects only data in fragments
5824 */
5825 if (!skb_has_frag_list(skb))
5826 skb_shinfo(skb)->frag_list = new_frag;
5827
5828 new_frag->next = NULL;
5829
5830 (*last_frag)->next = new_frag;
5831 *last_frag = new_frag;
5832
5833 skb->len += new_frag->len;
5834 skb->data_len += new_frag->len;
5835 skb->truesize += new_frag->truesize;
5836 }
5837
5838 static int l2cap_reassemble_sdu(struct l2cap_chan *chan, struct sk_buff *skb,
5839 struct l2cap_ctrl *control)
5840 {
5841 int err = -EINVAL;
5842
5843 switch (control->sar) {
5844 case L2CAP_SAR_UNSEGMENTED:
5845 if (chan->sdu)
5846 break;
5847
5848 err = chan->ops->recv(chan, skb);
5849 break;
5850
5851 case L2CAP_SAR_START:
5852 if (chan->sdu)
5853 break;
5854
5855 if (!pskb_may_pull(skb, L2CAP_SDULEN_SIZE))
5856 break;
5857
5858 chan->sdu_len = get_unaligned_le16(skb->data);
5859 skb_pull(skb, L2CAP_SDULEN_SIZE);
5860
5861 if (chan->sdu_len > chan->imtu) {
5862 err = -EMSGSIZE;
5863 break;
5864 }
5865
5866 if (skb->len >= chan->sdu_len)
5867 break;
5868
5869 chan->sdu = skb;
5870 chan->sdu_last_frag = skb;
5871
5872 skb = NULL;
5873 err = 0;
5874 break;
5875
5876 case L2CAP_SAR_CONTINUE:
5877 if (!chan->sdu)
5878 break;
5879
5880 append_skb_frag(chan->sdu, skb,
5881 &chan->sdu_last_frag);
5882 skb = NULL;
5883
5884 if (chan->sdu->len >= chan->sdu_len)
5885 break;
5886
5887 err = 0;
5888 break;
5889
5890 case L2CAP_SAR_END:
5891 if (!chan->sdu)
5892 break;
5893
5894 append_skb_frag(chan->sdu, skb,
5895 &chan->sdu_last_frag);
5896 skb = NULL;
5897
5898 if (chan->sdu->len != chan->sdu_len)
5899 break;
5900
5901 err = chan->ops->recv(chan, chan->sdu);
5902
5903 if (!err) {
5904 /* Reassembly complete */
5905 chan->sdu = NULL;
5906 chan->sdu_last_frag = NULL;
5907 chan->sdu_len = 0;
5908 }
5909 break;
5910 }
5911
5912 if (err) {
5913 kfree_skb(skb);
5914 kfree_skb(chan->sdu);
5915 chan->sdu = NULL;
5916 chan->sdu_last_frag = NULL;
5917 chan->sdu_len = 0;
5918 }
5919
5920 return err;
5921 }
5922
5923 static int l2cap_resegment(struct l2cap_chan *chan)
5924 {
5925 /* Placeholder */
5926 return 0;
5927 }
5928
5929 void l2cap_chan_busy(struct l2cap_chan *chan, int busy)
5930 {
5931 u8 event;
5932
5933 if (chan->mode != L2CAP_MODE_ERTM)
5934 return;
5935
5936 event = busy ? L2CAP_EV_LOCAL_BUSY_DETECTED : L2CAP_EV_LOCAL_BUSY_CLEAR;
5937 l2cap_tx(chan, NULL, NULL, event);
5938 }
5939
5940 static int l2cap_rx_queued_iframes(struct l2cap_chan *chan)
5941 {
5942 int err = 0;
5943 /* Pass sequential frames to l2cap_reassemble_sdu()
5944 * until a gap is encountered.
5945 */
5946
5947 BT_DBG("chan %p", chan);
5948
5949 while (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
5950 struct sk_buff *skb;
5951 BT_DBG("Searching for skb with txseq %d (queue len %d)",
5952 chan->buffer_seq, skb_queue_len(&chan->srej_q));
5953
5954 skb = l2cap_ertm_seq_in_queue(&chan->srej_q, chan->buffer_seq);
5955
5956 if (!skb)
5957 break;
5958
5959 skb_unlink(skb, &chan->srej_q);
5960 chan->buffer_seq = __next_seq(chan, chan->buffer_seq);
5961 err = l2cap_reassemble_sdu(chan, skb, &bt_cb(skb)->l2cap);
5962 if (err)
5963 break;
5964 }
5965
5966 if (skb_queue_empty(&chan->srej_q)) {
5967 chan->rx_state = L2CAP_RX_STATE_RECV;
5968 l2cap_send_ack(chan);
5969 }
5970
5971 return err;
5972 }
5973
5974 static void l2cap_handle_srej(struct l2cap_chan *chan,
5975 struct l2cap_ctrl *control)
5976 {
5977 struct sk_buff *skb;
5978
5979 BT_DBG("chan %p, control %p", chan, control);
5980
5981 if (control->reqseq == chan->next_tx_seq) {
5982 BT_DBG("Invalid reqseq %d, disconnecting", control->reqseq);
5983 l2cap_send_disconn_req(chan, ECONNRESET);
5984 return;
5985 }
5986
5987 skb = l2cap_ertm_seq_in_queue(&chan->tx_q, control->reqseq);
5988
5989 if (skb == NULL) {
5990 BT_DBG("Seq %d not available for retransmission",
5991 control->reqseq);
5992 return;
5993 }
5994
5995 if (chan->max_tx != 0 && bt_cb(skb)->l2cap.retries >= chan->max_tx) {
5996 BT_DBG("Retry limit exceeded (%d)", chan->max_tx);
5997 l2cap_send_disconn_req(chan, ECONNRESET);
5998 return;
5999 }
6000
6001 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6002
6003 if (control->poll) {
6004 l2cap_pass_to_tx(chan, control);
6005
6006 set_bit(CONN_SEND_FBIT, &chan->conn_state);
6007 l2cap_retransmit(chan, control);
6008 l2cap_ertm_send(chan);
6009
6010 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F) {
6011 set_bit(CONN_SREJ_ACT, &chan->conn_state);
6012 chan->srej_save_reqseq = control->reqseq;
6013 }
6014 } else {
6015 l2cap_pass_to_tx_fbit(chan, control);
6016
6017 if (control->final) {
6018 if (chan->srej_save_reqseq != control->reqseq ||
6019 !test_and_clear_bit(CONN_SREJ_ACT,
6020 &chan->conn_state))
6021 l2cap_retransmit(chan, control);
6022 } else {
6023 l2cap_retransmit(chan, control);
6024 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F) {
6025 set_bit(CONN_SREJ_ACT, &chan->conn_state);
6026 chan->srej_save_reqseq = control->reqseq;
6027 }
6028 }
6029 }
6030 }
6031
6032 static void l2cap_handle_rej(struct l2cap_chan *chan,
6033 struct l2cap_ctrl *control)
6034 {
6035 struct sk_buff *skb;
6036
6037 BT_DBG("chan %p, control %p", chan, control);
6038
6039 if (control->reqseq == chan->next_tx_seq) {
6040 BT_DBG("Invalid reqseq %d, disconnecting", control->reqseq);
6041 l2cap_send_disconn_req(chan, ECONNRESET);
6042 return;
6043 }
6044
6045 skb = l2cap_ertm_seq_in_queue(&chan->tx_q, control->reqseq);
6046
6047 if (chan->max_tx && skb &&
6048 bt_cb(skb)->l2cap.retries >= chan->max_tx) {
6049 BT_DBG("Retry limit exceeded (%d)", chan->max_tx);
6050 l2cap_send_disconn_req(chan, ECONNRESET);
6051 return;
6052 }
6053
6054 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6055
6056 l2cap_pass_to_tx(chan, control);
6057
6058 if (control->final) {
6059 if (!test_and_clear_bit(CONN_REJ_ACT, &chan->conn_state))
6060 l2cap_retransmit_all(chan, control);
6061 } else {
6062 l2cap_retransmit_all(chan, control);
6063 l2cap_ertm_send(chan);
6064 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F)
6065 set_bit(CONN_REJ_ACT, &chan->conn_state);
6066 }
6067 }
6068
6069 static u8 l2cap_classify_txseq(struct l2cap_chan *chan, u16 txseq)
6070 {
6071 BT_DBG("chan %p, txseq %d", chan, txseq);
6072
6073 BT_DBG("last_acked_seq %d, expected_tx_seq %d", chan->last_acked_seq,
6074 chan->expected_tx_seq);
6075
6076 if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) {
6077 if (__seq_offset(chan, txseq, chan->last_acked_seq) >=
6078 chan->tx_win) {
6079 /* See notes below regarding "double poll" and
6080 * invalid packets.
6081 */
6082 if (chan->tx_win <= ((chan->tx_win_max + 1) >> 1)) {
6083 BT_DBG("Invalid/Ignore - after SREJ");
6084 return L2CAP_TXSEQ_INVALID_IGNORE;
6085 } else {
6086 BT_DBG("Invalid - in window after SREJ sent");
6087 return L2CAP_TXSEQ_INVALID;
6088 }
6089 }
6090
6091 if (chan->srej_list.head == txseq) {
6092 BT_DBG("Expected SREJ");
6093 return L2CAP_TXSEQ_EXPECTED_SREJ;
6094 }
6095
6096 if (l2cap_ertm_seq_in_queue(&chan->srej_q, txseq)) {
6097 BT_DBG("Duplicate SREJ - txseq already stored");
6098 return L2CAP_TXSEQ_DUPLICATE_SREJ;
6099 }
6100
6101 if (l2cap_seq_list_contains(&chan->srej_list, txseq)) {
6102 BT_DBG("Unexpected SREJ - not requested");
6103 return L2CAP_TXSEQ_UNEXPECTED_SREJ;
6104 }
6105 }
6106
6107 if (chan->expected_tx_seq == txseq) {
6108 if (__seq_offset(chan, txseq, chan->last_acked_seq) >=
6109 chan->tx_win) {
6110 BT_DBG("Invalid - txseq outside tx window");
6111 return L2CAP_TXSEQ_INVALID;
6112 } else {
6113 BT_DBG("Expected");
6114 return L2CAP_TXSEQ_EXPECTED;
6115 }
6116 }
6117
6118 if (__seq_offset(chan, txseq, chan->last_acked_seq) <
6119 __seq_offset(chan, chan->expected_tx_seq, chan->last_acked_seq)) {
6120 BT_DBG("Duplicate - expected_tx_seq later than txseq");
6121 return L2CAP_TXSEQ_DUPLICATE;
6122 }
6123
6124 if (__seq_offset(chan, txseq, chan->last_acked_seq) >= chan->tx_win) {
6125 /* A source of invalid packets is a "double poll" condition,
6126 * where delays cause us to send multiple poll packets. If
6127 * the remote stack receives and processes both polls,
6128 * sequence numbers can wrap around in such a way that a
6129 * resent frame has a sequence number that looks like new data
6130 * with a sequence gap. This would trigger an erroneous SREJ
6131 * request.
6132 *
6133 * Fortunately, this is impossible with a tx window that's
6134 * less than half of the maximum sequence number, which allows
6135 * invalid frames to be safely ignored.
6136 *
6137 * With tx window sizes greater than half of the tx window
6138 * maximum, the frame is invalid and cannot be ignored. This
6139 * causes a disconnect.
6140 */
6141
6142 if (chan->tx_win <= ((chan->tx_win_max + 1) >> 1)) {
6143 BT_DBG("Invalid/Ignore - txseq outside tx window");
6144 return L2CAP_TXSEQ_INVALID_IGNORE;
6145 } else {
6146 BT_DBG("Invalid - txseq outside tx window");
6147 return L2CAP_TXSEQ_INVALID;
6148 }
6149 } else {
6150 BT_DBG("Unexpected - txseq indicates missing frames");
6151 return L2CAP_TXSEQ_UNEXPECTED;
6152 }
6153 }
6154
6155 static int l2cap_rx_state_recv(struct l2cap_chan *chan,
6156 struct l2cap_ctrl *control,
6157 struct sk_buff *skb, u8 event)
6158 {
6159 int err = 0;
6160 bool skb_in_use = false;
6161
6162 BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
6163 event);
6164
6165 switch (event) {
6166 case L2CAP_EV_RECV_IFRAME:
6167 switch (l2cap_classify_txseq(chan, control->txseq)) {
6168 case L2CAP_TXSEQ_EXPECTED:
6169 l2cap_pass_to_tx(chan, control);
6170
6171 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
6172 BT_DBG("Busy, discarding expected seq %d",
6173 control->txseq);
6174 break;
6175 }
6176
6177 chan->expected_tx_seq = __next_seq(chan,
6178 control->txseq);
6179
6180 chan->buffer_seq = chan->expected_tx_seq;
6181 skb_in_use = true;
6182
6183 err = l2cap_reassemble_sdu(chan, skb, control);
6184 if (err)
6185 break;
6186
6187 if (control->final) {
6188 if (!test_and_clear_bit(CONN_REJ_ACT,
6189 &chan->conn_state)) {
6190 control->final = 0;
6191 l2cap_retransmit_all(chan, control);
6192 l2cap_ertm_send(chan);
6193 }
6194 }
6195
6196 if (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state))
6197 l2cap_send_ack(chan);
6198 break;
6199 case L2CAP_TXSEQ_UNEXPECTED:
6200 l2cap_pass_to_tx(chan, control);
6201
6202 /* Can't issue SREJ frames in the local busy state.
6203 * Drop this frame, it will be seen as missing
6204 * when local busy is exited.
6205 */
6206 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
6207 BT_DBG("Busy, discarding unexpected seq %d",
6208 control->txseq);
6209 break;
6210 }
6211
6212 /* There was a gap in the sequence, so an SREJ
6213 * must be sent for each missing frame. The
6214 * current frame is stored for later use.
6215 */
6216 skb_queue_tail(&chan->srej_q, skb);
6217 skb_in_use = true;
6218 BT_DBG("Queued %p (queue len %d)", skb,
6219 skb_queue_len(&chan->srej_q));
6220
6221 clear_bit(CONN_SREJ_ACT, &chan->conn_state);
6222 l2cap_seq_list_clear(&chan->srej_list);
6223 l2cap_send_srej(chan, control->txseq);
6224
6225 chan->rx_state = L2CAP_RX_STATE_SREJ_SENT;
6226 break;
6227 case L2CAP_TXSEQ_DUPLICATE:
6228 l2cap_pass_to_tx(chan, control);
6229 break;
6230 case L2CAP_TXSEQ_INVALID_IGNORE:
6231 break;
6232 case L2CAP_TXSEQ_INVALID:
6233 default:
6234 l2cap_send_disconn_req(chan, ECONNRESET);
6235 break;
6236 }
6237 break;
6238 case L2CAP_EV_RECV_RR:
6239 l2cap_pass_to_tx(chan, control);
6240 if (control->final) {
6241 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6242
6243 if (!test_and_clear_bit(CONN_REJ_ACT, &chan->conn_state) &&
6244 !__chan_is_moving(chan)) {
6245 control->final = 0;
6246 l2cap_retransmit_all(chan, control);
6247 }
6248
6249 l2cap_ertm_send(chan);
6250 } else if (control->poll) {
6251 l2cap_send_i_or_rr_or_rnr(chan);
6252 } else {
6253 if (test_and_clear_bit(CONN_REMOTE_BUSY,
6254 &chan->conn_state) &&
6255 chan->unacked_frames)
6256 __set_retrans_timer(chan);
6257
6258 l2cap_ertm_send(chan);
6259 }
6260 break;
6261 case L2CAP_EV_RECV_RNR:
6262 set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6263 l2cap_pass_to_tx(chan, control);
6264 if (control && control->poll) {
6265 set_bit(CONN_SEND_FBIT, &chan->conn_state);
6266 l2cap_send_rr_or_rnr(chan, 0);
6267 }
6268 __clear_retrans_timer(chan);
6269 l2cap_seq_list_clear(&chan->retrans_list);
6270 break;
6271 case L2CAP_EV_RECV_REJ:
6272 l2cap_handle_rej(chan, control);
6273 break;
6274 case L2CAP_EV_RECV_SREJ:
6275 l2cap_handle_srej(chan, control);
6276 break;
6277 default:
6278 break;
6279 }
6280
6281 if (skb && !skb_in_use) {
6282 BT_DBG("Freeing %p", skb);
6283 kfree_skb(skb);
6284 }
6285
6286 return err;
6287 }
6288
6289 static int l2cap_rx_state_srej_sent(struct l2cap_chan *chan,
6290 struct l2cap_ctrl *control,
6291 struct sk_buff *skb, u8 event)
6292 {
6293 int err = 0;
6294 u16 txseq = control->txseq;
6295 bool skb_in_use = false;
6296
6297 BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
6298 event);
6299
6300 switch (event) {
6301 case L2CAP_EV_RECV_IFRAME:
6302 switch (l2cap_classify_txseq(chan, txseq)) {
6303 case L2CAP_TXSEQ_EXPECTED:
6304 /* Keep frame for reassembly later */
6305 l2cap_pass_to_tx(chan, control);
6306 skb_queue_tail(&chan->srej_q, skb);
6307 skb_in_use = true;
6308 BT_DBG("Queued %p (queue len %d)", skb,
6309 skb_queue_len(&chan->srej_q));
6310
6311 chan->expected_tx_seq = __next_seq(chan, txseq);
6312 break;
6313 case L2CAP_TXSEQ_EXPECTED_SREJ:
6314 l2cap_seq_list_pop(&chan->srej_list);
6315
6316 l2cap_pass_to_tx(chan, control);
6317 skb_queue_tail(&chan->srej_q, skb);
6318 skb_in_use = true;
6319 BT_DBG("Queued %p (queue len %d)", skb,
6320 skb_queue_len(&chan->srej_q));
6321
6322 err = l2cap_rx_queued_iframes(chan);
6323 if (err)
6324 break;
6325
6326 break;
6327 case L2CAP_TXSEQ_UNEXPECTED:
6328 /* Got a frame that can't be reassembled yet.
6329 * Save it for later, and send SREJs to cover
6330 * the missing frames.
6331 */
6332 skb_queue_tail(&chan->srej_q, skb);
6333 skb_in_use = true;
6334 BT_DBG("Queued %p (queue len %d)", skb,
6335 skb_queue_len(&chan->srej_q));
6336
6337 l2cap_pass_to_tx(chan, control);
6338 l2cap_send_srej(chan, control->txseq);
6339 break;
6340 case L2CAP_TXSEQ_UNEXPECTED_SREJ:
6341 /* This frame was requested with an SREJ, but
6342 * some expected retransmitted frames are
6343 * missing. Request retransmission of missing
6344 * SREJ'd frames.
6345 */
6346 skb_queue_tail(&chan->srej_q, skb);
6347 skb_in_use = true;
6348 BT_DBG("Queued %p (queue len %d)", skb,
6349 skb_queue_len(&chan->srej_q));
6350
6351 l2cap_pass_to_tx(chan, control);
6352 l2cap_send_srej_list(chan, control->txseq);
6353 break;
6354 case L2CAP_TXSEQ_DUPLICATE_SREJ:
6355 /* We've already queued this frame. Drop this copy. */
6356 l2cap_pass_to_tx(chan, control);
6357 break;
6358 case L2CAP_TXSEQ_DUPLICATE:
6359 /* Expecting a later sequence number, so this frame
6360 * was already received. Ignore it completely.
6361 */
6362 break;
6363 case L2CAP_TXSEQ_INVALID_IGNORE:
6364 break;
6365 case L2CAP_TXSEQ_INVALID:
6366 default:
6367 l2cap_send_disconn_req(chan, ECONNRESET);
6368 break;
6369 }
6370 break;
6371 case L2CAP_EV_RECV_RR:
6372 l2cap_pass_to_tx(chan, control);
6373 if (control->final) {
6374 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6375
6376 if (!test_and_clear_bit(CONN_REJ_ACT,
6377 &chan->conn_state)) {
6378 control->final = 0;
6379 l2cap_retransmit_all(chan, control);
6380 }
6381
6382 l2cap_ertm_send(chan);
6383 } else if (control->poll) {
6384 if (test_and_clear_bit(CONN_REMOTE_BUSY,
6385 &chan->conn_state) &&
6386 chan->unacked_frames) {
6387 __set_retrans_timer(chan);
6388 }
6389
6390 set_bit(CONN_SEND_FBIT, &chan->conn_state);
6391 l2cap_send_srej_tail(chan);
6392 } else {
6393 if (test_and_clear_bit(CONN_REMOTE_BUSY,
6394 &chan->conn_state) &&
6395 chan->unacked_frames)
6396 __set_retrans_timer(chan);
6397
6398 l2cap_send_ack(chan);
6399 }
6400 break;
6401 case L2CAP_EV_RECV_RNR:
6402 set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6403 l2cap_pass_to_tx(chan, control);
6404 if (control->poll) {
6405 l2cap_send_srej_tail(chan);
6406 } else {
6407 struct l2cap_ctrl rr_control;
6408 memset(&rr_control, 0, sizeof(rr_control));
6409 rr_control.sframe = 1;
6410 rr_control.super = L2CAP_SUPER_RR;
6411 rr_control.reqseq = chan->buffer_seq;
6412 l2cap_send_sframe(chan, &rr_control);
6413 }
6414
6415 break;
6416 case L2CAP_EV_RECV_REJ:
6417 l2cap_handle_rej(chan, control);
6418 break;
6419 case L2CAP_EV_RECV_SREJ:
6420 l2cap_handle_srej(chan, control);
6421 break;
6422 }
6423
6424 if (skb && !skb_in_use) {
6425 BT_DBG("Freeing %p", skb);
6426 kfree_skb(skb);
6427 }
6428
6429 return err;
6430 }
6431
6432 static int l2cap_finish_move(struct l2cap_chan *chan)
6433 {
6434 BT_DBG("chan %p", chan);
6435
6436 chan->rx_state = L2CAP_RX_STATE_RECV;
6437
6438 if (chan->hs_hcon)
6439 chan->conn->mtu = chan->hs_hcon->hdev->block_mtu;
6440 else
6441 chan->conn->mtu = chan->conn->hcon->hdev->acl_mtu;
6442
6443 return l2cap_resegment(chan);
6444 }
6445
6446 static int l2cap_rx_state_wait_p(struct l2cap_chan *chan,
6447 struct l2cap_ctrl *control,
6448 struct sk_buff *skb, u8 event)
6449 {
6450 int err;
6451
6452 BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
6453 event);
6454
6455 if (!control->poll)
6456 return -EPROTO;
6457
6458 l2cap_process_reqseq(chan, control->reqseq);
6459
6460 if (!skb_queue_empty(&chan->tx_q))
6461 chan->tx_send_head = skb_peek(&chan->tx_q);
6462 else
6463 chan->tx_send_head = NULL;
6464
6465 /* Rewind next_tx_seq to the point expected
6466 * by the receiver.
6467 */
6468 chan->next_tx_seq = control->reqseq;
6469 chan->unacked_frames = 0;
6470
6471 err = l2cap_finish_move(chan);
6472 if (err)
6473 return err;
6474
6475 set_bit(CONN_SEND_FBIT, &chan->conn_state);
6476 l2cap_send_i_or_rr_or_rnr(chan);
6477
6478 if (event == L2CAP_EV_RECV_IFRAME)
6479 return -EPROTO;
6480
6481 return l2cap_rx_state_recv(chan, control, NULL, event);
6482 }
6483
6484 static int l2cap_rx_state_wait_f(struct l2cap_chan *chan,
6485 struct l2cap_ctrl *control,
6486 struct sk_buff *skb, u8 event)
6487 {
6488 int err;
6489
6490 if (!control->final)
6491 return -EPROTO;
6492
6493 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6494
6495 chan->rx_state = L2CAP_RX_STATE_RECV;
6496 l2cap_process_reqseq(chan, control->reqseq);
6497
6498 if (!skb_queue_empty(&chan->tx_q))
6499 chan->tx_send_head = skb_peek(&chan->tx_q);
6500 else
6501 chan->tx_send_head = NULL;
6502
6503 /* Rewind next_tx_seq to the point expected
6504 * by the receiver.
6505 */
6506 chan->next_tx_seq = control->reqseq;
6507 chan->unacked_frames = 0;
6508
6509 if (chan->hs_hcon)
6510 chan->conn->mtu = chan->hs_hcon->hdev->block_mtu;
6511 else
6512 chan->conn->mtu = chan->conn->hcon->hdev->acl_mtu;
6513
6514 err = l2cap_resegment(chan);
6515
6516 if (!err)
6517 err = l2cap_rx_state_recv(chan, control, skb, event);
6518
6519 return err;
6520 }
6521
6522 static bool __valid_reqseq(struct l2cap_chan *chan, u16 reqseq)
6523 {
6524 /* Make sure reqseq is for a packet that has been sent but not acked */
6525 u16 unacked;
6526
6527 unacked = __seq_offset(chan, chan->next_tx_seq, chan->expected_ack_seq);
6528 return __seq_offset(chan, chan->next_tx_seq, reqseq) <= unacked;
6529 }
6530
6531 static int l2cap_rx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
6532 struct sk_buff *skb, u8 event)
6533 {
6534 int err = 0;
6535
6536 BT_DBG("chan %p, control %p, skb %p, event %d, state %d", chan,
6537 control, skb, event, chan->rx_state);
6538
6539 if (__valid_reqseq(chan, control->reqseq)) {
6540 switch (chan->rx_state) {
6541 case L2CAP_RX_STATE_RECV:
6542 err = l2cap_rx_state_recv(chan, control, skb, event);
6543 break;
6544 case L2CAP_RX_STATE_SREJ_SENT:
6545 err = l2cap_rx_state_srej_sent(chan, control, skb,
6546 event);
6547 break;
6548 case L2CAP_RX_STATE_WAIT_P:
6549 err = l2cap_rx_state_wait_p(chan, control, skb, event);
6550 break;
6551 case L2CAP_RX_STATE_WAIT_F:
6552 err = l2cap_rx_state_wait_f(chan, control, skb, event);
6553 break;
6554 default:
6555 /* shut it down */
6556 break;
6557 }
6558 } else {
6559 BT_DBG("Invalid reqseq %d (next_tx_seq %d, expected_ack_seq %d",
6560 control->reqseq, chan->next_tx_seq,
6561 chan->expected_ack_seq);
6562 l2cap_send_disconn_req(chan, ECONNRESET);
6563 }
6564
6565 return err;
6566 }
6567
6568 static int l2cap_stream_rx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
6569 struct sk_buff *skb)
6570 {
6571 BT_DBG("chan %p, control %p, skb %p, state %d", chan, control, skb,
6572 chan->rx_state);
6573
6574 if (l2cap_classify_txseq(chan, control->txseq) ==
6575 L2CAP_TXSEQ_EXPECTED) {
6576 l2cap_pass_to_tx(chan, control);
6577
6578 BT_DBG("buffer_seq %d->%d", chan->buffer_seq,
6579 __next_seq(chan, chan->buffer_seq));
6580
6581 chan->buffer_seq = __next_seq(chan, chan->buffer_seq);
6582
6583 l2cap_reassemble_sdu(chan, skb, control);
6584 } else {
6585 if (chan->sdu) {
6586 kfree_skb(chan->sdu);
6587 chan->sdu = NULL;
6588 }
6589 chan->sdu_last_frag = NULL;
6590 chan->sdu_len = 0;
6591
6592 if (skb) {
6593 BT_DBG("Freeing %p", skb);
6594 kfree_skb(skb);
6595 }
6596 }
6597
6598 chan->last_acked_seq = control->txseq;
6599 chan->expected_tx_seq = __next_seq(chan, control->txseq);
6600
6601 return 0;
6602 }
6603
6604 static int l2cap_data_rcv(struct l2cap_chan *chan, struct sk_buff *skb)
6605 {
6606 struct l2cap_ctrl *control = &bt_cb(skb)->l2cap;
6607 u16 len;
6608 u8 event;
6609
6610 __unpack_control(chan, skb);
6611
6612 len = skb->len;
6613
6614 /*
6615 * We can just drop the corrupted I-frame here.
6616 * Receiver will miss it and start proper recovery
6617 * procedures and ask for retransmission.
6618 */
6619 if (l2cap_check_fcs(chan, skb))
6620 goto drop;
6621
6622 if (!control->sframe && control->sar == L2CAP_SAR_START)
6623 len -= L2CAP_SDULEN_SIZE;
6624
6625 if (chan->fcs == L2CAP_FCS_CRC16)
6626 len -= L2CAP_FCS_SIZE;
6627
6628 if (len > chan->mps) {
6629 l2cap_send_disconn_req(chan, ECONNRESET);
6630 goto drop;
6631 }
6632
6633 if ((chan->mode == L2CAP_MODE_ERTM ||
6634 chan->mode == L2CAP_MODE_STREAMING) && sk_filter(chan->data, skb))
6635 goto drop;
6636
6637 if (!control->sframe) {
6638 int err;
6639
6640 BT_DBG("iframe sar %d, reqseq %d, final %d, txseq %d",
6641 control->sar, control->reqseq, control->final,
6642 control->txseq);
6643
6644 /* Validate F-bit - F=0 always valid, F=1 only
6645 * valid in TX WAIT_F
6646 */
6647 if (control->final && chan->tx_state != L2CAP_TX_STATE_WAIT_F)
6648 goto drop;
6649
6650 if (chan->mode != L2CAP_MODE_STREAMING) {
6651 event = L2CAP_EV_RECV_IFRAME;
6652 err = l2cap_rx(chan, control, skb, event);
6653 } else {
6654 err = l2cap_stream_rx(chan, control, skb);
6655 }
6656
6657 if (err)
6658 l2cap_send_disconn_req(chan, ECONNRESET);
6659 } else {
6660 const u8 rx_func_to_event[4] = {
6661 L2CAP_EV_RECV_RR, L2CAP_EV_RECV_REJ,
6662 L2CAP_EV_RECV_RNR, L2CAP_EV_RECV_SREJ
6663 };
6664
6665 /* Only I-frames are expected in streaming mode */
6666 if (chan->mode == L2CAP_MODE_STREAMING)
6667 goto drop;
6668
6669 BT_DBG("sframe reqseq %d, final %d, poll %d, super %d",
6670 control->reqseq, control->final, control->poll,
6671 control->super);
6672
6673 if (len != 0) {
6674 BT_ERR("Trailing bytes: %d in sframe", len);
6675 l2cap_send_disconn_req(chan, ECONNRESET);
6676 goto drop;
6677 }
6678
6679 /* Validate F and P bits */
6680 if (control->final && (control->poll ||
6681 chan->tx_state != L2CAP_TX_STATE_WAIT_F))
6682 goto drop;
6683
6684 event = rx_func_to_event[control->super];
6685 if (l2cap_rx(chan, control, skb, event))
6686 l2cap_send_disconn_req(chan, ECONNRESET);
6687 }
6688
6689 return 0;
6690
6691 drop:
6692 kfree_skb(skb);
6693 return 0;
6694 }
6695
6696 static void l2cap_chan_le_send_credits(struct l2cap_chan *chan)
6697 {
6698 struct l2cap_conn *conn = chan->conn;
6699 struct l2cap_le_credits pkt;
6700 u16 return_credits;
6701
6702 /* We return more credits to the sender only after the amount of
6703 * credits falls below half of the initial amount.
6704 */
6705 if (chan->rx_credits >= (le_max_credits + 1) / 2)
6706 return;
6707
6708 return_credits = le_max_credits - chan->rx_credits;
6709
6710 BT_DBG("chan %p returning %u credits to sender", chan, return_credits);
6711
6712 chan->rx_credits += return_credits;
6713
6714 pkt.cid = cpu_to_le16(chan->scid);
6715 pkt.credits = cpu_to_le16(return_credits);
6716
6717 chan->ident = l2cap_get_ident(conn);
6718
6719 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CREDITS, sizeof(pkt), &pkt);
6720 }
6721
6722 static int l2cap_le_data_rcv(struct l2cap_chan *chan, struct sk_buff *skb)
6723 {
6724 int err;
6725
6726 if (!chan->rx_credits) {
6727 BT_ERR("No credits to receive LE L2CAP data");
6728 l2cap_send_disconn_req(chan, ECONNRESET);
6729 return -ENOBUFS;
6730 }
6731
6732 if (chan->imtu < skb->len) {
6733 BT_ERR("Too big LE L2CAP PDU");
6734 return -ENOBUFS;
6735 }
6736
6737 chan->rx_credits--;
6738 BT_DBG("rx_credits %u -> %u", chan->rx_credits + 1, chan->rx_credits);
6739
6740 l2cap_chan_le_send_credits(chan);
6741
6742 err = 0;
6743
6744 if (!chan->sdu) {
6745 u16 sdu_len;
6746
6747 sdu_len = get_unaligned_le16(skb->data);
6748 skb_pull(skb, L2CAP_SDULEN_SIZE);
6749
6750 BT_DBG("Start of new SDU. sdu_len %u skb->len %u imtu %u",
6751 sdu_len, skb->len, chan->imtu);
6752
6753 if (sdu_len > chan->imtu) {
6754 BT_ERR("Too big LE L2CAP SDU length received");
6755 err = -EMSGSIZE;
6756 goto failed;
6757 }
6758
6759 if (skb->len > sdu_len) {
6760 BT_ERR("Too much LE L2CAP data received");
6761 err = -EINVAL;
6762 goto failed;
6763 }
6764
6765 if (skb->len == sdu_len)
6766 return chan->ops->recv(chan, skb);
6767
6768 chan->sdu = skb;
6769 chan->sdu_len = sdu_len;
6770 chan->sdu_last_frag = skb;
6771
6772 return 0;
6773 }
6774
6775 BT_DBG("SDU fragment. chan->sdu->len %u skb->len %u chan->sdu_len %u",
6776 chan->sdu->len, skb->len, chan->sdu_len);
6777
6778 if (chan->sdu->len + skb->len > chan->sdu_len) {
6779 BT_ERR("Too much LE L2CAP data received");
6780 err = -EINVAL;
6781 goto failed;
6782 }
6783
6784 append_skb_frag(chan->sdu, skb, &chan->sdu_last_frag);
6785 skb = NULL;
6786
6787 if (chan->sdu->len == chan->sdu_len) {
6788 err = chan->ops->recv(chan, chan->sdu);
6789 if (!err) {
6790 chan->sdu = NULL;
6791 chan->sdu_last_frag = NULL;
6792 chan->sdu_len = 0;
6793 }
6794 }
6795
6796 failed:
6797 if (err) {
6798 kfree_skb(skb);
6799 kfree_skb(chan->sdu);
6800 chan->sdu = NULL;
6801 chan->sdu_last_frag = NULL;
6802 chan->sdu_len = 0;
6803 }
6804
6805 /* We can't return an error here since we took care of the skb
6806 * freeing internally. An error return would cause the caller to
6807 * do a double-free of the skb.
6808 */
6809 return 0;
6810 }
6811
6812 static void l2cap_data_channel(struct l2cap_conn *conn, u16 cid,
6813 struct sk_buff *skb)
6814 {
6815 struct l2cap_chan *chan;
6816
6817 chan = l2cap_get_chan_by_scid(conn, cid);
6818 if (!chan) {
6819 if (cid == L2CAP_CID_A2MP) {
6820 chan = a2mp_channel_create(conn, skb);
6821 if (!chan) {
6822 kfree_skb(skb);
6823 return;
6824 }
6825
6826 l2cap_chan_lock(chan);
6827 } else {
6828 BT_DBG("unknown cid 0x%4.4x", cid);
6829 /* Drop packet and return */
6830 kfree_skb(skb);
6831 return;
6832 }
6833 }
6834
6835 BT_DBG("chan %p, len %d", chan, skb->len);
6836
6837 /* If we receive data on a fixed channel before the info req/rsp
6838 * procdure is done simply assume that the channel is supported
6839 * and mark it as ready.
6840 */
6841 if (chan->chan_type == L2CAP_CHAN_FIXED)
6842 l2cap_chan_ready(chan);
6843
6844 if (chan->state != BT_CONNECTED)
6845 goto drop;
6846
6847 switch (chan->mode) {
6848 case L2CAP_MODE_LE_FLOWCTL:
6849 if (l2cap_le_data_rcv(chan, skb) < 0)
6850 goto drop;
6851
6852 goto done;
6853
6854 case L2CAP_MODE_BASIC:
6855 /* If socket recv buffers overflows we drop data here
6856 * which is *bad* because L2CAP has to be reliable.
6857 * But we don't have any other choice. L2CAP doesn't
6858 * provide flow control mechanism. */
6859
6860 if (chan->imtu < skb->len) {
6861 BT_ERR("Dropping L2CAP data: receive buffer overflow");
6862 goto drop;
6863 }
6864
6865 if (!chan->ops->recv(chan, skb))
6866 goto done;
6867 break;
6868
6869 case L2CAP_MODE_ERTM:
6870 case L2CAP_MODE_STREAMING:
6871 l2cap_data_rcv(chan, skb);
6872 goto done;
6873
6874 default:
6875 BT_DBG("chan %p: bad mode 0x%2.2x", chan, chan->mode);
6876 break;
6877 }
6878
6879 drop:
6880 kfree_skb(skb);
6881
6882 done:
6883 l2cap_chan_unlock(chan);
6884 }
6885
6886 static void l2cap_conless_channel(struct l2cap_conn *conn, __le16 psm,
6887 struct sk_buff *skb)
6888 {
6889 struct hci_conn *hcon = conn->hcon;
6890 struct l2cap_chan *chan;
6891
6892 if (hcon->type != ACL_LINK)
6893 goto free_skb;
6894
6895 chan = l2cap_global_chan_by_psm(0, psm, &hcon->src, &hcon->dst,
6896 ACL_LINK);
6897 if (!chan)
6898 goto free_skb;
6899
6900 BT_DBG("chan %p, len %d", chan, skb->len);
6901
6902 if (chan->state != BT_BOUND && chan->state != BT_CONNECTED)
6903 goto drop;
6904
6905 if (chan->imtu < skb->len)
6906 goto drop;
6907
6908 /* Store remote BD_ADDR and PSM for msg_name */
6909 bacpy(&bt_cb(skb)->l2cap.bdaddr, &hcon->dst);
6910 bt_cb(skb)->l2cap.psm = psm;
6911
6912 if (!chan->ops->recv(chan, skb)) {
6913 l2cap_chan_put(chan);
6914 return;
6915 }
6916
6917 drop:
6918 l2cap_chan_put(chan);
6919 free_skb:
6920 kfree_skb(skb);
6921 }
6922
6923 static void l2cap_recv_frame(struct l2cap_conn *conn, struct sk_buff *skb)
6924 {
6925 struct l2cap_hdr *lh = (void *) skb->data;
6926 struct hci_conn *hcon = conn->hcon;
6927 u16 cid, len;
6928 __le16 psm;
6929
6930 if (hcon->state != BT_CONNECTED) {
6931 BT_DBG("queueing pending rx skb");
6932 skb_queue_tail(&conn->pending_rx, skb);
6933 return;
6934 }
6935
6936 skb_pull(skb, L2CAP_HDR_SIZE);
6937 cid = __le16_to_cpu(lh->cid);
6938 len = __le16_to_cpu(lh->len);
6939
6940 if (len != skb->len) {
6941 kfree_skb(skb);
6942 return;
6943 }
6944
6945 /* Since we can't actively block incoming LE connections we must
6946 * at least ensure that we ignore incoming data from them.
6947 */
6948 if (hcon->type == LE_LINK &&
6949 hci_bdaddr_list_lookup(&hcon->hdev->blacklist, &hcon->dst,
6950 bdaddr_dst_type(hcon))) {
6951 kfree_skb(skb);
6952 return;
6953 }
6954
6955 BT_DBG("len %d, cid 0x%4.4x", len, cid);
6956
6957 switch (cid) {
6958 case L2CAP_CID_SIGNALING:
6959 l2cap_sig_channel(conn, skb);
6960 break;
6961
6962 case L2CAP_CID_CONN_LESS:
6963 psm = get_unaligned((__le16 *) skb->data);
6964 skb_pull(skb, L2CAP_PSMLEN_SIZE);
6965 l2cap_conless_channel(conn, psm, skb);
6966 break;
6967
6968 case L2CAP_CID_LE_SIGNALING:
6969 l2cap_le_sig_channel(conn, skb);
6970 break;
6971
6972 default:
6973 l2cap_data_channel(conn, cid, skb);
6974 break;
6975 }
6976 }
6977
6978 static void process_pending_rx(struct work_struct *work)
6979 {
6980 struct l2cap_conn *conn = container_of(work, struct l2cap_conn,
6981 pending_rx_work);
6982 struct sk_buff *skb;
6983
6984 BT_DBG("");
6985
6986 while ((skb = skb_dequeue(&conn->pending_rx)))
6987 l2cap_recv_frame(conn, skb);
6988 }
6989
6990 static struct l2cap_conn *l2cap_conn_add(struct hci_conn *hcon)
6991 {
6992 struct l2cap_conn *conn = hcon->l2cap_data;
6993 struct hci_chan *hchan;
6994
6995 if (conn)
6996 return conn;
6997
6998 hchan = hci_chan_create(hcon);
6999 if (!hchan)
7000 return NULL;
7001
7002 conn = kzalloc(sizeof(*conn), GFP_KERNEL);
7003 if (!conn) {
7004 hci_chan_del(hchan);
7005 return NULL;
7006 }
7007
7008 kref_init(&conn->ref);
7009 hcon->l2cap_data = conn;
7010 conn->hcon = hci_conn_get(hcon);
7011 conn->hchan = hchan;
7012
7013 BT_DBG("hcon %p conn %p hchan %p", hcon, conn, hchan);
7014
7015 switch (hcon->type) {
7016 case LE_LINK:
7017 if (hcon->hdev->le_mtu) {
7018 conn->mtu = hcon->hdev->le_mtu;
7019 break;
7020 }
7021 /* fall through */
7022 default:
7023 conn->mtu = hcon->hdev->acl_mtu;
7024 break;
7025 }
7026
7027 conn->feat_mask = 0;
7028
7029 conn->local_fixed_chan = L2CAP_FC_SIG_BREDR | L2CAP_FC_CONNLESS;
7030
7031 if (hcon->type == ACL_LINK &&
7032 hci_dev_test_flag(hcon->hdev, HCI_HS_ENABLED))
7033 conn->local_fixed_chan |= L2CAP_FC_A2MP;
7034
7035 if (hci_dev_test_flag(hcon->hdev, HCI_LE_ENABLED) &&
7036 (bredr_sc_enabled(hcon->hdev) ||
7037 hci_dev_test_flag(hcon->hdev, HCI_FORCE_BREDR_SMP)))
7038 conn->local_fixed_chan |= L2CAP_FC_SMP_BREDR;
7039
7040 mutex_init(&conn->ident_lock);
7041 mutex_init(&conn->chan_lock);
7042
7043 INIT_LIST_HEAD(&conn->chan_l);
7044 INIT_LIST_HEAD(&conn->users);
7045
7046 INIT_DELAYED_WORK(&conn->info_timer, l2cap_info_timeout);
7047
7048 skb_queue_head_init(&conn->pending_rx);
7049 INIT_WORK(&conn->pending_rx_work, process_pending_rx);
7050 INIT_WORK(&conn->id_addr_update_work, l2cap_conn_update_id_addr);
7051
7052 conn->disc_reason = HCI_ERROR_REMOTE_USER_TERM;
7053
7054 return conn;
7055 }
7056
7057 static bool is_valid_psm(u16 psm, u8 dst_type) {
7058 if (!psm)
7059 return false;
7060
7061 if (bdaddr_type_is_le(dst_type))
7062 return (psm <= 0x00ff);
7063
7064 /* PSM must be odd and lsb of upper byte must be 0 */
7065 return ((psm & 0x0101) == 0x0001);
7066 }
7067
7068 int l2cap_chan_connect(struct l2cap_chan *chan, __le16 psm, u16 cid,
7069 bdaddr_t *dst, u8 dst_type)
7070 {
7071 struct l2cap_conn *conn;
7072 struct hci_conn *hcon;
7073 struct hci_dev *hdev;
7074 int err;
7075
7076 BT_DBG("%pMR -> %pMR (type %u) psm 0x%2.2x", &chan->src, dst,
7077 dst_type, __le16_to_cpu(psm));
7078
7079 hdev = hci_get_route(dst, &chan->src, chan->src_type);
7080 if (!hdev)
7081 return -EHOSTUNREACH;
7082
7083 hci_dev_lock(hdev);
7084
7085 if (!is_valid_psm(__le16_to_cpu(psm), dst_type) && !cid &&
7086 chan->chan_type != L2CAP_CHAN_RAW) {
7087 err = -EINVAL;
7088 goto done;
7089 }
7090
7091 if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED && !psm) {
7092 err = -EINVAL;
7093 goto done;
7094 }
7095
7096 if (chan->chan_type == L2CAP_CHAN_FIXED && !cid) {
7097 err = -EINVAL;
7098 goto done;
7099 }
7100
7101 switch (chan->mode) {
7102 case L2CAP_MODE_BASIC:
7103 break;
7104 case L2CAP_MODE_LE_FLOWCTL:
7105 l2cap_le_flowctl_init(chan);
7106 break;
7107 case L2CAP_MODE_ERTM:
7108 case L2CAP_MODE_STREAMING:
7109 if (!disable_ertm)
7110 break;
7111 /* fall through */
7112 default:
7113 err = -EOPNOTSUPP;
7114 goto done;
7115 }
7116
7117 switch (chan->state) {
7118 case BT_CONNECT:
7119 case BT_CONNECT2:
7120 case BT_CONFIG:
7121 /* Already connecting */
7122 err = 0;
7123 goto done;
7124
7125 case BT_CONNECTED:
7126 /* Already connected */
7127 err = -EISCONN;
7128 goto done;
7129
7130 case BT_OPEN:
7131 case BT_BOUND:
7132 /* Can connect */
7133 break;
7134
7135 default:
7136 err = -EBADFD;
7137 goto done;
7138 }
7139
7140 /* Set destination address and psm */
7141 bacpy(&chan->dst, dst);
7142 chan->dst_type = dst_type;
7143
7144 chan->psm = psm;
7145 chan->dcid = cid;
7146
7147 if (bdaddr_type_is_le(dst_type)) {
7148 /* Convert from L2CAP channel address type to HCI address type
7149 */
7150 if (dst_type == BDADDR_LE_PUBLIC)
7151 dst_type = ADDR_LE_DEV_PUBLIC;
7152 else
7153 dst_type = ADDR_LE_DEV_RANDOM;
7154
7155 if (hci_dev_test_flag(hdev, HCI_ADVERTISING))
7156 hcon = hci_connect_le(hdev, dst, dst_type,
7157 chan->sec_level,
7158 HCI_LE_CONN_TIMEOUT,
7159 HCI_ROLE_SLAVE, NULL);
7160 else
7161 hcon = hci_connect_le_scan(hdev, dst, dst_type,
7162 chan->sec_level,
7163 HCI_LE_CONN_TIMEOUT);
7164
7165 } else {
7166 u8 auth_type = l2cap_get_auth_type(chan);
7167 hcon = hci_connect_acl(hdev, dst, chan->sec_level, auth_type);
7168 }
7169
7170 if (IS_ERR(hcon)) {
7171 err = PTR_ERR(hcon);
7172 goto done;
7173 }
7174
7175 conn = l2cap_conn_add(hcon);
7176 if (!conn) {
7177 hci_conn_drop(hcon);
7178 err = -ENOMEM;
7179 goto done;
7180 }
7181
7182 mutex_lock(&conn->chan_lock);
7183 l2cap_chan_lock(chan);
7184
7185 if (cid && __l2cap_get_chan_by_dcid(conn, cid)) {
7186 hci_conn_drop(hcon);
7187 err = -EBUSY;
7188 goto chan_unlock;
7189 }
7190
7191 /* Update source addr of the socket */
7192 bacpy(&chan->src, &hcon->src);
7193 chan->src_type = bdaddr_src_type(hcon);
7194
7195 __l2cap_chan_add(conn, chan);
7196
7197 /* l2cap_chan_add takes its own ref so we can drop this one */
7198 hci_conn_drop(hcon);
7199
7200 l2cap_state_change(chan, BT_CONNECT);
7201 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
7202
7203 /* Release chan->sport so that it can be reused by other
7204 * sockets (as it's only used for listening sockets).
7205 */
7206 write_lock(&chan_list_lock);
7207 chan->sport = 0;
7208 write_unlock(&chan_list_lock);
7209
7210 if (hcon->state == BT_CONNECTED) {
7211 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
7212 __clear_chan_timer(chan);
7213 if (l2cap_chan_check_security(chan, true))
7214 l2cap_state_change(chan, BT_CONNECTED);
7215 } else
7216 l2cap_do_start(chan);
7217 }
7218
7219 err = 0;
7220
7221 chan_unlock:
7222 l2cap_chan_unlock(chan);
7223 mutex_unlock(&conn->chan_lock);
7224 done:
7225 hci_dev_unlock(hdev);
7226 hci_dev_put(hdev);
7227 return err;
7228 }
7229 EXPORT_SYMBOL_GPL(l2cap_chan_connect);
7230
7231 /* ---- L2CAP interface with lower layer (HCI) ---- */
7232
7233 int l2cap_connect_ind(struct hci_dev *hdev, bdaddr_t *bdaddr)
7234 {
7235 int exact = 0, lm1 = 0, lm2 = 0;
7236 struct l2cap_chan *c;
7237
7238 BT_DBG("hdev %s, bdaddr %pMR", hdev->name, bdaddr);
7239
7240 /* Find listening sockets and check their link_mode */
7241 read_lock(&chan_list_lock);
7242 list_for_each_entry(c, &chan_list, global_l) {
7243 if (c->state != BT_LISTEN)
7244 continue;
7245
7246 if (!bacmp(&c->src, &hdev->bdaddr)) {
7247 lm1 |= HCI_LM_ACCEPT;
7248 if (test_bit(FLAG_ROLE_SWITCH, &c->flags))
7249 lm1 |= HCI_LM_MASTER;
7250 exact++;
7251 } else if (!bacmp(&c->src, BDADDR_ANY)) {
7252 lm2 |= HCI_LM_ACCEPT;
7253 if (test_bit(FLAG_ROLE_SWITCH, &c->flags))
7254 lm2 |= HCI_LM_MASTER;
7255 }
7256 }
7257 read_unlock(&chan_list_lock);
7258
7259 return exact ? lm1 : lm2;
7260 }
7261
7262 /* Find the next fixed channel in BT_LISTEN state, continue iteration
7263 * from an existing channel in the list or from the beginning of the
7264 * global list (by passing NULL as first parameter).
7265 */
7266 static struct l2cap_chan *l2cap_global_fixed_chan(struct l2cap_chan *c,
7267 struct hci_conn *hcon)
7268 {
7269 u8 src_type = bdaddr_src_type(hcon);
7270
7271 read_lock(&chan_list_lock);
7272
7273 if (c)
7274 c = list_next_entry(c, global_l);
7275 else
7276 c = list_entry(chan_list.next, typeof(*c), global_l);
7277
7278 list_for_each_entry_from(c, &chan_list, global_l) {
7279 if (c->chan_type != L2CAP_CHAN_FIXED)
7280 continue;
7281 if (c->state != BT_LISTEN)
7282 continue;
7283 if (bacmp(&c->src, &hcon->src) && bacmp(&c->src, BDADDR_ANY))
7284 continue;
7285 if (src_type != c->src_type)
7286 continue;
7287
7288 l2cap_chan_hold(c);
7289 read_unlock(&chan_list_lock);
7290 return c;
7291 }
7292
7293 read_unlock(&chan_list_lock);
7294
7295 return NULL;
7296 }
7297
7298 static void l2cap_connect_cfm(struct hci_conn *hcon, u8 status)
7299 {
7300 struct hci_dev *hdev = hcon->hdev;
7301 struct l2cap_conn *conn;
7302 struct l2cap_chan *pchan;
7303 u8 dst_type;
7304
7305 if (hcon->type != ACL_LINK && hcon->type != LE_LINK)
7306 return;
7307
7308 BT_DBG("hcon %p bdaddr %pMR status %d", hcon, &hcon->dst, status);
7309
7310 if (status) {
7311 l2cap_conn_del(hcon, bt_to_errno(status));
7312 return;
7313 }
7314
7315 conn = l2cap_conn_add(hcon);
7316 if (!conn)
7317 return;
7318
7319 dst_type = bdaddr_dst_type(hcon);
7320
7321 /* If device is blocked, do not create channels for it */
7322 if (hci_bdaddr_list_lookup(&hdev->blacklist, &hcon->dst, dst_type))
7323 return;
7324
7325 /* Find fixed channels and notify them of the new connection. We
7326 * use multiple individual lookups, continuing each time where
7327 * we left off, because the list lock would prevent calling the
7328 * potentially sleeping l2cap_chan_lock() function.
7329 */
7330 pchan = l2cap_global_fixed_chan(NULL, hcon);
7331 while (pchan) {
7332 struct l2cap_chan *chan, *next;
7333
7334 /* Client fixed channels should override server ones */
7335 if (__l2cap_get_chan_by_dcid(conn, pchan->scid))
7336 goto next;
7337
7338 l2cap_chan_lock(pchan);
7339 chan = pchan->ops->new_connection(pchan);
7340 if (chan) {
7341 bacpy(&chan->src, &hcon->src);
7342 bacpy(&chan->dst, &hcon->dst);
7343 chan->src_type = bdaddr_src_type(hcon);
7344 chan->dst_type = dst_type;
7345
7346 __l2cap_chan_add(conn, chan);
7347 }
7348
7349 l2cap_chan_unlock(pchan);
7350 next:
7351 next = l2cap_global_fixed_chan(pchan, hcon);
7352 l2cap_chan_put(pchan);
7353 pchan = next;
7354 }
7355
7356 l2cap_conn_ready(conn);
7357 }
7358
7359 int l2cap_disconn_ind(struct hci_conn *hcon)
7360 {
7361 struct l2cap_conn *conn = hcon->l2cap_data;
7362
7363 BT_DBG("hcon %p", hcon);
7364
7365 if (!conn)
7366 return HCI_ERROR_REMOTE_USER_TERM;
7367 return conn->disc_reason;
7368 }
7369
7370 static void l2cap_disconn_cfm(struct hci_conn *hcon, u8 reason)
7371 {
7372 if (hcon->type != ACL_LINK && hcon->type != LE_LINK)
7373 return;
7374
7375 BT_DBG("hcon %p reason %d", hcon, reason);
7376
7377 l2cap_conn_del(hcon, bt_to_errno(reason));
7378 }
7379
7380 static inline void l2cap_check_encryption(struct l2cap_chan *chan, u8 encrypt)
7381 {
7382 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED)
7383 return;
7384
7385 if (encrypt == 0x00) {
7386 if (chan->sec_level == BT_SECURITY_MEDIUM) {
7387 __set_chan_timer(chan, L2CAP_ENC_TIMEOUT);
7388 } else if (chan->sec_level == BT_SECURITY_HIGH ||
7389 chan->sec_level == BT_SECURITY_FIPS)
7390 l2cap_chan_close(chan, ECONNREFUSED);
7391 } else {
7392 if (chan->sec_level == BT_SECURITY_MEDIUM)
7393 __clear_chan_timer(chan);
7394 }
7395 }
7396
7397 static void l2cap_security_cfm(struct hci_conn *hcon, u8 status, u8 encrypt)
7398 {
7399 struct l2cap_conn *conn = hcon->l2cap_data;
7400 struct l2cap_chan *chan;
7401
7402 if (!conn)
7403 return;
7404
7405 BT_DBG("conn %p status 0x%2.2x encrypt %u", conn, status, encrypt);
7406
7407 mutex_lock(&conn->chan_lock);
7408
7409 list_for_each_entry(chan, &conn->chan_l, list) {
7410 l2cap_chan_lock(chan);
7411
7412 BT_DBG("chan %p scid 0x%4.4x state %s", chan, chan->scid,
7413 state_to_string(chan->state));
7414
7415 if (chan->scid == L2CAP_CID_A2MP) {
7416 l2cap_chan_unlock(chan);
7417 continue;
7418 }
7419
7420 if (!status && encrypt)
7421 chan->sec_level = hcon->sec_level;
7422
7423 if (!__l2cap_no_conn_pending(chan)) {
7424 l2cap_chan_unlock(chan);
7425 continue;
7426 }
7427
7428 if (!status && (chan->state == BT_CONNECTED ||
7429 chan->state == BT_CONFIG)) {
7430 chan->ops->resume(chan);
7431 l2cap_check_encryption(chan, encrypt);
7432 l2cap_chan_unlock(chan);
7433 continue;
7434 }
7435
7436 if (chan->state == BT_CONNECT) {
7437 if (!status)
7438 l2cap_start_connection(chan);
7439 else
7440 __set_chan_timer(chan, L2CAP_DISC_TIMEOUT);
7441 } else if (chan->state == BT_CONNECT2 &&
7442 chan->mode != L2CAP_MODE_LE_FLOWCTL) {
7443 struct l2cap_conn_rsp rsp;
7444 __u16 res, stat;
7445
7446 if (!status) {
7447 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
7448 res = L2CAP_CR_PEND;
7449 stat = L2CAP_CS_AUTHOR_PEND;
7450 chan->ops->defer(chan);
7451 } else {
7452 l2cap_state_change(chan, BT_CONFIG);
7453 res = L2CAP_CR_SUCCESS;
7454 stat = L2CAP_CS_NO_INFO;
7455 }
7456 } else {
7457 l2cap_state_change(chan, BT_DISCONN);
7458 __set_chan_timer(chan, L2CAP_DISC_TIMEOUT);
7459 res = L2CAP_CR_SEC_BLOCK;
7460 stat = L2CAP_CS_NO_INFO;
7461 }
7462
7463 rsp.scid = cpu_to_le16(chan->dcid);
7464 rsp.dcid = cpu_to_le16(chan->scid);
7465 rsp.result = cpu_to_le16(res);
7466 rsp.status = cpu_to_le16(stat);
7467 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP,
7468 sizeof(rsp), &rsp);
7469
7470 if (!test_bit(CONF_REQ_SENT, &chan->conf_state) &&
7471 res == L2CAP_CR_SUCCESS) {
7472 char buf[128];
7473 set_bit(CONF_REQ_SENT, &chan->conf_state);
7474 l2cap_send_cmd(conn, l2cap_get_ident(conn),
7475 L2CAP_CONF_REQ,
7476 l2cap_build_conf_req(chan, buf, sizeof(buf)),
7477 buf);
7478 chan->num_conf_req++;
7479 }
7480 }
7481
7482 l2cap_chan_unlock(chan);
7483 }
7484
7485 mutex_unlock(&conn->chan_lock);
7486 }
7487
7488 void l2cap_recv_acldata(struct hci_conn *hcon, struct sk_buff *skb, u16 flags)
7489 {
7490 struct l2cap_conn *conn = hcon->l2cap_data;
7491 struct l2cap_hdr *hdr;
7492 int len;
7493
7494 /* For AMP controller do not create l2cap conn */
7495 if (!conn && hcon->hdev->dev_type != HCI_PRIMARY)
7496 goto drop;
7497
7498 if (!conn)
7499 conn = l2cap_conn_add(hcon);
7500
7501 if (!conn)
7502 goto drop;
7503
7504 BT_DBG("conn %p len %d flags 0x%x", conn, skb->len, flags);
7505
7506 switch (flags) {
7507 case ACL_START:
7508 case ACL_START_NO_FLUSH:
7509 case ACL_COMPLETE:
7510 if (conn->rx_len) {
7511 BT_ERR("Unexpected start frame (len %d)", skb->len);
7512 kfree_skb(conn->rx_skb);
7513 conn->rx_skb = NULL;
7514 conn->rx_len = 0;
7515 l2cap_conn_unreliable(conn, ECOMM);
7516 }
7517
7518 /* Start fragment always begin with Basic L2CAP header */
7519 if (skb->len < L2CAP_HDR_SIZE) {
7520 BT_ERR("Frame is too short (len %d)", skb->len);
7521 l2cap_conn_unreliable(conn, ECOMM);
7522 goto drop;
7523 }
7524
7525 hdr = (struct l2cap_hdr *) skb->data;
7526 len = __le16_to_cpu(hdr->len) + L2CAP_HDR_SIZE;
7527
7528 if (len == skb->len) {
7529 /* Complete frame received */
7530 l2cap_recv_frame(conn, skb);
7531 return;
7532 }
7533
7534 BT_DBG("Start: total len %d, frag len %d", len, skb->len);
7535
7536 if (skb->len > len) {
7537 BT_ERR("Frame is too long (len %d, expected len %d)",
7538 skb->len, len);
7539 l2cap_conn_unreliable(conn, ECOMM);
7540 goto drop;
7541 }
7542
7543 /* Allocate skb for the complete frame (with header) */
7544 conn->rx_skb = bt_skb_alloc(len, GFP_KERNEL);
7545 if (!conn->rx_skb)
7546 goto drop;
7547
7548 skb_copy_from_linear_data(skb, skb_put(conn->rx_skb, skb->len),
7549 skb->len);
7550 conn->rx_len = len - skb->len;
7551 break;
7552
7553 case ACL_CONT:
7554 BT_DBG("Cont: frag len %d (expecting %d)", skb->len, conn->rx_len);
7555
7556 if (!conn->rx_len) {
7557 BT_ERR("Unexpected continuation frame (len %d)", skb->len);
7558 l2cap_conn_unreliable(conn, ECOMM);
7559 goto drop;
7560 }
7561
7562 if (skb->len > conn->rx_len) {
7563 BT_ERR("Fragment is too long (len %d, expected %d)",
7564 skb->len, conn->rx_len);
7565 kfree_skb(conn->rx_skb);
7566 conn->rx_skb = NULL;
7567 conn->rx_len = 0;
7568 l2cap_conn_unreliable(conn, ECOMM);
7569 goto drop;
7570 }
7571
7572 skb_copy_from_linear_data(skb, skb_put(conn->rx_skb, skb->len),
7573 skb->len);
7574 conn->rx_len -= skb->len;
7575
7576 if (!conn->rx_len) {
7577 /* Complete frame received. l2cap_recv_frame
7578 * takes ownership of the skb so set the global
7579 * rx_skb pointer to NULL first.
7580 */
7581 struct sk_buff *rx_skb = conn->rx_skb;
7582 conn->rx_skb = NULL;
7583 l2cap_recv_frame(conn, rx_skb);
7584 }
7585 break;
7586 }
7587
7588 drop:
7589 kfree_skb(skb);
7590 }
7591
7592 static struct hci_cb l2cap_cb = {
7593 .name = "L2CAP",
7594 .connect_cfm = l2cap_connect_cfm,
7595 .disconn_cfm = l2cap_disconn_cfm,
7596 .security_cfm = l2cap_security_cfm,
7597 };
7598
7599 static int l2cap_debugfs_show(struct seq_file *f, void *p)
7600 {
7601 struct l2cap_chan *c;
7602
7603 read_lock(&chan_list_lock);
7604
7605 list_for_each_entry(c, &chan_list, global_l) {
7606 seq_printf(f, "%pMR (%u) %pMR (%u) %d %d 0x%4.4x 0x%4.4x %d %d %d %d\n",
7607 &c->src, c->src_type, &c->dst, c->dst_type,
7608 c->state, __le16_to_cpu(c->psm),
7609 c->scid, c->dcid, c->imtu, c->omtu,
7610 c->sec_level, c->mode);
7611 }
7612
7613 read_unlock(&chan_list_lock);
7614
7615 return 0;
7616 }
7617
7618 static int l2cap_debugfs_open(struct inode *inode, struct file *file)
7619 {
7620 return single_open(file, l2cap_debugfs_show, inode->i_private);
7621 }
7622
7623 static const struct file_operations l2cap_debugfs_fops = {
7624 .open = l2cap_debugfs_open,
7625 .read = seq_read,
7626 .llseek = seq_lseek,
7627 .release = single_release,
7628 };
7629
7630 static struct dentry *l2cap_debugfs;
7631
7632 int __init l2cap_init(void)
7633 {
7634 int err;
7635
7636 err = l2cap_init_sockets();
7637 if (err < 0)
7638 return err;
7639
7640 hci_register_cb(&l2cap_cb);
7641
7642 if (IS_ERR_OR_NULL(bt_debugfs))
7643 return 0;
7644
7645 l2cap_debugfs = debugfs_create_file("l2cap", 0444, bt_debugfs,
7646 NULL, &l2cap_debugfs_fops);
7647
7648 debugfs_create_u16("l2cap_le_max_credits", 0644, bt_debugfs,
7649 &le_max_credits);
7650 debugfs_create_u16("l2cap_le_default_mps", 0644, bt_debugfs,
7651 &le_default_mps);
7652
7653 return 0;
7654 }
7655
7656 void l2cap_exit(void)
7657 {
7658 debugfs_remove(l2cap_debugfs);
7659 hci_unregister_cb(&l2cap_cb);
7660 l2cap_cleanup_sockets();
7661 }
7662
7663 module_param(disable_ertm, bool, 0644);
7664 MODULE_PARM_DESC(disable_ertm, "Disable enhanced retransmission mode");
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