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Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
[mirror_ubuntu-jammy-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 struct sk_buff *l2cap_build_cmd(struct l2cap_conn *conn,
55 u8 code, u8 ident, u16 dlen, void *data);
56 static void l2cap_send_cmd(struct l2cap_conn *conn, u8 ident, u8 code, u16 len,
57 void *data);
58 static int l2cap_build_conf_req(struct l2cap_chan *chan, void *data, size_t data_size);
59 static void l2cap_send_disconn_req(struct l2cap_chan *chan, int err);
60
61 static void l2cap_tx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
62 struct sk_buff_head *skbs, u8 event);
63
64 static inline u8 bdaddr_type(u8 link_type, u8 bdaddr_type)
65 {
66 if (link_type == LE_LINK) {
67 if (bdaddr_type == ADDR_LE_DEV_PUBLIC)
68 return BDADDR_LE_PUBLIC;
69 else
70 return BDADDR_LE_RANDOM;
71 }
72
73 return BDADDR_BREDR;
74 }
75
76 static inline u8 bdaddr_src_type(struct hci_conn *hcon)
77 {
78 return bdaddr_type(hcon->type, hcon->src_type);
79 }
80
81 static inline u8 bdaddr_dst_type(struct hci_conn *hcon)
82 {
83 return bdaddr_type(hcon->type, hcon->dst_type);
84 }
85
86 /* ---- L2CAP channels ---- */
87
88 static struct l2cap_chan *__l2cap_get_chan_by_dcid(struct l2cap_conn *conn,
89 u16 cid)
90 {
91 struct l2cap_chan *c;
92
93 list_for_each_entry(c, &conn->chan_l, list) {
94 if (c->dcid == cid)
95 return c;
96 }
97 return NULL;
98 }
99
100 static struct l2cap_chan *__l2cap_get_chan_by_scid(struct l2cap_conn *conn,
101 u16 cid)
102 {
103 struct l2cap_chan *c;
104
105 list_for_each_entry(c, &conn->chan_l, list) {
106 if (c->scid == cid)
107 return c;
108 }
109 return NULL;
110 }
111
112 /* Find channel with given SCID.
113 * Returns locked channel. */
114 static struct l2cap_chan *l2cap_get_chan_by_scid(struct l2cap_conn *conn,
115 u16 cid)
116 {
117 struct l2cap_chan *c;
118
119 mutex_lock(&conn->chan_lock);
120 c = __l2cap_get_chan_by_scid(conn, cid);
121 if (c)
122 l2cap_chan_lock(c);
123 mutex_unlock(&conn->chan_lock);
124
125 return c;
126 }
127
128 /* Find channel with given DCID.
129 * Returns locked channel.
130 */
131 static struct l2cap_chan *l2cap_get_chan_by_dcid(struct l2cap_conn *conn,
132 u16 cid)
133 {
134 struct l2cap_chan *c;
135
136 mutex_lock(&conn->chan_lock);
137 c = __l2cap_get_chan_by_dcid(conn, cid);
138 if (c)
139 l2cap_chan_lock(c);
140 mutex_unlock(&conn->chan_lock);
141
142 return c;
143 }
144
145 static struct l2cap_chan *__l2cap_get_chan_by_ident(struct l2cap_conn *conn,
146 u8 ident)
147 {
148 struct l2cap_chan *c;
149
150 list_for_each_entry(c, &conn->chan_l, list) {
151 if (c->ident == ident)
152 return c;
153 }
154 return NULL;
155 }
156
157 static struct l2cap_chan *l2cap_get_chan_by_ident(struct l2cap_conn *conn,
158 u8 ident)
159 {
160 struct l2cap_chan *c;
161
162 mutex_lock(&conn->chan_lock);
163 c = __l2cap_get_chan_by_ident(conn, ident);
164 if (c)
165 l2cap_chan_lock(c);
166 mutex_unlock(&conn->chan_lock);
167
168 return c;
169 }
170
171 static struct l2cap_chan *__l2cap_global_chan_by_addr(__le16 psm, bdaddr_t *src,
172 u8 src_type)
173 {
174 struct l2cap_chan *c;
175
176 list_for_each_entry(c, &chan_list, global_l) {
177 if (src_type == BDADDR_BREDR && c->src_type != BDADDR_BREDR)
178 continue;
179
180 if (src_type != BDADDR_BREDR && c->src_type == BDADDR_BREDR)
181 continue;
182
183 if (c->sport == psm && !bacmp(&c->src, src))
184 return c;
185 }
186 return NULL;
187 }
188
189 int l2cap_add_psm(struct l2cap_chan *chan, bdaddr_t *src, __le16 psm)
190 {
191 int err;
192
193 write_lock(&chan_list_lock);
194
195 if (psm && __l2cap_global_chan_by_addr(psm, src, chan->src_type)) {
196 err = -EADDRINUSE;
197 goto done;
198 }
199
200 if (psm) {
201 chan->psm = psm;
202 chan->sport = psm;
203 err = 0;
204 } else {
205 u16 p, start, end, incr;
206
207 if (chan->src_type == BDADDR_BREDR) {
208 start = L2CAP_PSM_DYN_START;
209 end = L2CAP_PSM_AUTO_END;
210 incr = 2;
211 } else {
212 start = L2CAP_PSM_LE_DYN_START;
213 end = L2CAP_PSM_LE_DYN_END;
214 incr = 1;
215 }
216
217 err = -EINVAL;
218 for (p = start; p <= end; p += incr)
219 if (!__l2cap_global_chan_by_addr(cpu_to_le16(p), src,
220 chan->src_type)) {
221 chan->psm = cpu_to_le16(p);
222 chan->sport = cpu_to_le16(p);
223 err = 0;
224 break;
225 }
226 }
227
228 done:
229 write_unlock(&chan_list_lock);
230 return err;
231 }
232 EXPORT_SYMBOL_GPL(l2cap_add_psm);
233
234 int l2cap_add_scid(struct l2cap_chan *chan, __u16 scid)
235 {
236 write_lock(&chan_list_lock);
237
238 /* Override the defaults (which are for conn-oriented) */
239 chan->omtu = L2CAP_DEFAULT_MTU;
240 chan->chan_type = L2CAP_CHAN_FIXED;
241
242 chan->scid = scid;
243
244 write_unlock(&chan_list_lock);
245
246 return 0;
247 }
248
249 static u16 l2cap_alloc_cid(struct l2cap_conn *conn)
250 {
251 u16 cid, dyn_end;
252
253 if (conn->hcon->type == LE_LINK)
254 dyn_end = L2CAP_CID_LE_DYN_END;
255 else
256 dyn_end = L2CAP_CID_DYN_END;
257
258 for (cid = L2CAP_CID_DYN_START; cid <= dyn_end; cid++) {
259 if (!__l2cap_get_chan_by_scid(conn, cid))
260 return cid;
261 }
262
263 return 0;
264 }
265
266 static void l2cap_state_change(struct l2cap_chan *chan, int state)
267 {
268 BT_DBG("chan %p %s -> %s", chan, state_to_string(chan->state),
269 state_to_string(state));
270
271 chan->state = state;
272 chan->ops->state_change(chan, state, 0);
273 }
274
275 static inline void l2cap_state_change_and_error(struct l2cap_chan *chan,
276 int state, int err)
277 {
278 chan->state = state;
279 chan->ops->state_change(chan, chan->state, err);
280 }
281
282 static inline void l2cap_chan_set_err(struct l2cap_chan *chan, int err)
283 {
284 chan->ops->state_change(chan, chan->state, err);
285 }
286
287 static void __set_retrans_timer(struct l2cap_chan *chan)
288 {
289 if (!delayed_work_pending(&chan->monitor_timer) &&
290 chan->retrans_timeout) {
291 l2cap_set_timer(chan, &chan->retrans_timer,
292 msecs_to_jiffies(chan->retrans_timeout));
293 }
294 }
295
296 static void __set_monitor_timer(struct l2cap_chan *chan)
297 {
298 __clear_retrans_timer(chan);
299 if (chan->monitor_timeout) {
300 l2cap_set_timer(chan, &chan->monitor_timer,
301 msecs_to_jiffies(chan->monitor_timeout));
302 }
303 }
304
305 static struct sk_buff *l2cap_ertm_seq_in_queue(struct sk_buff_head *head,
306 u16 seq)
307 {
308 struct sk_buff *skb;
309
310 skb_queue_walk(head, skb) {
311 if (bt_cb(skb)->l2cap.txseq == seq)
312 return skb;
313 }
314
315 return NULL;
316 }
317
318 /* ---- L2CAP sequence number lists ---- */
319
320 /* For ERTM, ordered lists of sequence numbers must be tracked for
321 * SREJ requests that are received and for frames that are to be
322 * retransmitted. These seq_list functions implement a singly-linked
323 * list in an array, where membership in the list can also be checked
324 * in constant time. Items can also be added to the tail of the list
325 * and removed from the head in constant time, without further memory
326 * allocs or frees.
327 */
328
329 static int l2cap_seq_list_init(struct l2cap_seq_list *seq_list, u16 size)
330 {
331 size_t alloc_size, i;
332
333 /* Allocated size is a power of 2 to map sequence numbers
334 * (which may be up to 14 bits) in to a smaller array that is
335 * sized for the negotiated ERTM transmit windows.
336 */
337 alloc_size = roundup_pow_of_two(size);
338
339 seq_list->list = kmalloc_array(alloc_size, sizeof(u16), GFP_KERNEL);
340 if (!seq_list->list)
341 return -ENOMEM;
342
343 seq_list->mask = alloc_size - 1;
344 seq_list->head = L2CAP_SEQ_LIST_CLEAR;
345 seq_list->tail = L2CAP_SEQ_LIST_CLEAR;
346 for (i = 0; i < alloc_size; i++)
347 seq_list->list[i] = L2CAP_SEQ_LIST_CLEAR;
348
349 return 0;
350 }
351
352 static inline void l2cap_seq_list_free(struct l2cap_seq_list *seq_list)
353 {
354 kfree(seq_list->list);
355 }
356
357 static inline bool l2cap_seq_list_contains(struct l2cap_seq_list *seq_list,
358 u16 seq)
359 {
360 /* Constant-time check for list membership */
361 return seq_list->list[seq & seq_list->mask] != L2CAP_SEQ_LIST_CLEAR;
362 }
363
364 static inline u16 l2cap_seq_list_pop(struct l2cap_seq_list *seq_list)
365 {
366 u16 seq = seq_list->head;
367 u16 mask = seq_list->mask;
368
369 seq_list->head = seq_list->list[seq & mask];
370 seq_list->list[seq & mask] = L2CAP_SEQ_LIST_CLEAR;
371
372 if (seq_list->head == L2CAP_SEQ_LIST_TAIL) {
373 seq_list->head = L2CAP_SEQ_LIST_CLEAR;
374 seq_list->tail = L2CAP_SEQ_LIST_CLEAR;
375 }
376
377 return seq;
378 }
379
380 static void l2cap_seq_list_clear(struct l2cap_seq_list *seq_list)
381 {
382 u16 i;
383
384 if (seq_list->head == L2CAP_SEQ_LIST_CLEAR)
385 return;
386
387 for (i = 0; i <= seq_list->mask; i++)
388 seq_list->list[i] = L2CAP_SEQ_LIST_CLEAR;
389
390 seq_list->head = L2CAP_SEQ_LIST_CLEAR;
391 seq_list->tail = L2CAP_SEQ_LIST_CLEAR;
392 }
393
394 static void l2cap_seq_list_append(struct l2cap_seq_list *seq_list, u16 seq)
395 {
396 u16 mask = seq_list->mask;
397
398 /* All appends happen in constant time */
399
400 if (seq_list->list[seq & mask] != L2CAP_SEQ_LIST_CLEAR)
401 return;
402
403 if (seq_list->tail == L2CAP_SEQ_LIST_CLEAR)
404 seq_list->head = seq;
405 else
406 seq_list->list[seq_list->tail & mask] = seq;
407
408 seq_list->tail = seq;
409 seq_list->list[seq & mask] = L2CAP_SEQ_LIST_TAIL;
410 }
411
412 static void l2cap_chan_timeout(struct work_struct *work)
413 {
414 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
415 chan_timer.work);
416 struct l2cap_conn *conn = chan->conn;
417 int reason;
418
419 BT_DBG("chan %p state %s", chan, state_to_string(chan->state));
420
421 mutex_lock(&conn->chan_lock);
422 l2cap_chan_lock(chan);
423
424 if (chan->state == BT_CONNECTED || chan->state == BT_CONFIG)
425 reason = ECONNREFUSED;
426 else if (chan->state == BT_CONNECT &&
427 chan->sec_level != BT_SECURITY_SDP)
428 reason = ECONNREFUSED;
429 else
430 reason = ETIMEDOUT;
431
432 l2cap_chan_close(chan, reason);
433
434 l2cap_chan_unlock(chan);
435
436 chan->ops->close(chan);
437 mutex_unlock(&conn->chan_lock);
438
439 l2cap_chan_put(chan);
440 }
441
442 struct l2cap_chan *l2cap_chan_create(void)
443 {
444 struct l2cap_chan *chan;
445
446 chan = kzalloc(sizeof(*chan), GFP_ATOMIC);
447 if (!chan)
448 return NULL;
449
450 mutex_init(&chan->lock);
451
452 /* Set default lock nesting level */
453 atomic_set(&chan->nesting, L2CAP_NESTING_NORMAL);
454
455 write_lock(&chan_list_lock);
456 list_add(&chan->global_l, &chan_list);
457 write_unlock(&chan_list_lock);
458
459 INIT_DELAYED_WORK(&chan->chan_timer, l2cap_chan_timeout);
460
461 chan->state = BT_OPEN;
462
463 kref_init(&chan->kref);
464
465 /* This flag is cleared in l2cap_chan_ready() */
466 set_bit(CONF_NOT_COMPLETE, &chan->conf_state);
467
468 BT_DBG("chan %p", chan);
469
470 return chan;
471 }
472 EXPORT_SYMBOL_GPL(l2cap_chan_create);
473
474 static void l2cap_chan_destroy(struct kref *kref)
475 {
476 struct l2cap_chan *chan = container_of(kref, struct l2cap_chan, kref);
477
478 BT_DBG("chan %p", chan);
479
480 write_lock(&chan_list_lock);
481 list_del(&chan->global_l);
482 write_unlock(&chan_list_lock);
483
484 kfree(chan);
485 }
486
487 void l2cap_chan_hold(struct l2cap_chan *c)
488 {
489 BT_DBG("chan %p orig refcnt %d", c, kref_read(&c->kref));
490
491 kref_get(&c->kref);
492 }
493
494 void l2cap_chan_put(struct l2cap_chan *c)
495 {
496 BT_DBG("chan %p orig refcnt %d", c, kref_read(&c->kref));
497
498 kref_put(&c->kref, l2cap_chan_destroy);
499 }
500 EXPORT_SYMBOL_GPL(l2cap_chan_put);
501
502 void l2cap_chan_set_defaults(struct l2cap_chan *chan)
503 {
504 chan->fcs = L2CAP_FCS_CRC16;
505 chan->max_tx = L2CAP_DEFAULT_MAX_TX;
506 chan->tx_win = L2CAP_DEFAULT_TX_WINDOW;
507 chan->tx_win_max = L2CAP_DEFAULT_TX_WINDOW;
508 chan->remote_max_tx = chan->max_tx;
509 chan->remote_tx_win = chan->tx_win;
510 chan->ack_win = L2CAP_DEFAULT_TX_WINDOW;
511 chan->sec_level = BT_SECURITY_LOW;
512 chan->flush_to = L2CAP_DEFAULT_FLUSH_TO;
513 chan->retrans_timeout = L2CAP_DEFAULT_RETRANS_TO;
514 chan->monitor_timeout = L2CAP_DEFAULT_MONITOR_TO;
515 chan->conf_state = 0;
516
517 set_bit(FLAG_FORCE_ACTIVE, &chan->flags);
518 }
519 EXPORT_SYMBOL_GPL(l2cap_chan_set_defaults);
520
521 static void l2cap_le_flowctl_init(struct l2cap_chan *chan, u16 tx_credits)
522 {
523 chan->sdu = NULL;
524 chan->sdu_last_frag = NULL;
525 chan->sdu_len = 0;
526 chan->tx_credits = tx_credits;
527 /* Derive MPS from connection MTU to stop HCI fragmentation */
528 chan->mps = min_t(u16, chan->imtu, chan->conn->mtu - L2CAP_HDR_SIZE);
529 /* Give enough credits for a full packet */
530 chan->rx_credits = (chan->imtu / chan->mps) + 1;
531
532 skb_queue_head_init(&chan->tx_q);
533 }
534
535 void __l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan)
536 {
537 BT_DBG("conn %p, psm 0x%2.2x, dcid 0x%4.4x", conn,
538 __le16_to_cpu(chan->psm), chan->dcid);
539
540 conn->disc_reason = HCI_ERROR_REMOTE_USER_TERM;
541
542 chan->conn = conn;
543
544 switch (chan->chan_type) {
545 case L2CAP_CHAN_CONN_ORIENTED:
546 /* Alloc CID for connection-oriented socket */
547 chan->scid = l2cap_alloc_cid(conn);
548 if (conn->hcon->type == ACL_LINK)
549 chan->omtu = L2CAP_DEFAULT_MTU;
550 break;
551
552 case L2CAP_CHAN_CONN_LESS:
553 /* Connectionless socket */
554 chan->scid = L2CAP_CID_CONN_LESS;
555 chan->dcid = L2CAP_CID_CONN_LESS;
556 chan->omtu = L2CAP_DEFAULT_MTU;
557 break;
558
559 case L2CAP_CHAN_FIXED:
560 /* Caller will set CID and CID specific MTU values */
561 break;
562
563 default:
564 /* Raw socket can send/recv signalling messages only */
565 chan->scid = L2CAP_CID_SIGNALING;
566 chan->dcid = L2CAP_CID_SIGNALING;
567 chan->omtu = L2CAP_DEFAULT_MTU;
568 }
569
570 chan->local_id = L2CAP_BESTEFFORT_ID;
571 chan->local_stype = L2CAP_SERV_BESTEFFORT;
572 chan->local_msdu = L2CAP_DEFAULT_MAX_SDU_SIZE;
573 chan->local_sdu_itime = L2CAP_DEFAULT_SDU_ITIME;
574 chan->local_acc_lat = L2CAP_DEFAULT_ACC_LAT;
575 chan->local_flush_to = L2CAP_EFS_DEFAULT_FLUSH_TO;
576
577 l2cap_chan_hold(chan);
578
579 /* Only keep a reference for fixed channels if they requested it */
580 if (chan->chan_type != L2CAP_CHAN_FIXED ||
581 test_bit(FLAG_HOLD_HCI_CONN, &chan->flags))
582 hci_conn_hold(conn->hcon);
583
584 list_add(&chan->list, &conn->chan_l);
585 }
586
587 void l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan)
588 {
589 mutex_lock(&conn->chan_lock);
590 __l2cap_chan_add(conn, chan);
591 mutex_unlock(&conn->chan_lock);
592 }
593
594 void l2cap_chan_del(struct l2cap_chan *chan, int err)
595 {
596 struct l2cap_conn *conn = chan->conn;
597
598 __clear_chan_timer(chan);
599
600 BT_DBG("chan %p, conn %p, err %d, state %s", chan, conn, err,
601 state_to_string(chan->state));
602
603 chan->ops->teardown(chan, err);
604
605 if (conn) {
606 struct amp_mgr *mgr = conn->hcon->amp_mgr;
607 /* Delete from channel list */
608 list_del(&chan->list);
609
610 l2cap_chan_put(chan);
611
612 chan->conn = NULL;
613
614 /* Reference was only held for non-fixed channels or
615 * fixed channels that explicitly requested it using the
616 * FLAG_HOLD_HCI_CONN flag.
617 */
618 if (chan->chan_type != L2CAP_CHAN_FIXED ||
619 test_bit(FLAG_HOLD_HCI_CONN, &chan->flags))
620 hci_conn_drop(conn->hcon);
621
622 if (mgr && mgr->bredr_chan == chan)
623 mgr->bredr_chan = NULL;
624 }
625
626 if (chan->hs_hchan) {
627 struct hci_chan *hs_hchan = chan->hs_hchan;
628
629 BT_DBG("chan %p disconnect hs_hchan %p", chan, hs_hchan);
630 amp_disconnect_logical_link(hs_hchan);
631 }
632
633 if (test_bit(CONF_NOT_COMPLETE, &chan->conf_state))
634 return;
635
636 switch(chan->mode) {
637 case L2CAP_MODE_BASIC:
638 break;
639
640 case L2CAP_MODE_LE_FLOWCTL:
641 skb_queue_purge(&chan->tx_q);
642 break;
643
644 case L2CAP_MODE_ERTM:
645 __clear_retrans_timer(chan);
646 __clear_monitor_timer(chan);
647 __clear_ack_timer(chan);
648
649 skb_queue_purge(&chan->srej_q);
650
651 l2cap_seq_list_free(&chan->srej_list);
652 l2cap_seq_list_free(&chan->retrans_list);
653
654 /* fall through */
655
656 case L2CAP_MODE_STREAMING:
657 skb_queue_purge(&chan->tx_q);
658 break;
659 }
660
661 return;
662 }
663 EXPORT_SYMBOL_GPL(l2cap_chan_del);
664
665 static void l2cap_conn_update_id_addr(struct work_struct *work)
666 {
667 struct l2cap_conn *conn = container_of(work, struct l2cap_conn,
668 id_addr_update_work);
669 struct hci_conn *hcon = conn->hcon;
670 struct l2cap_chan *chan;
671
672 mutex_lock(&conn->chan_lock);
673
674 list_for_each_entry(chan, &conn->chan_l, list) {
675 l2cap_chan_lock(chan);
676 bacpy(&chan->dst, &hcon->dst);
677 chan->dst_type = bdaddr_dst_type(hcon);
678 l2cap_chan_unlock(chan);
679 }
680
681 mutex_unlock(&conn->chan_lock);
682 }
683
684 static void l2cap_chan_le_connect_reject(struct l2cap_chan *chan)
685 {
686 struct l2cap_conn *conn = chan->conn;
687 struct l2cap_le_conn_rsp rsp;
688 u16 result;
689
690 if (test_bit(FLAG_DEFER_SETUP, &chan->flags))
691 result = L2CAP_CR_LE_AUTHORIZATION;
692 else
693 result = L2CAP_CR_LE_BAD_PSM;
694
695 l2cap_state_change(chan, BT_DISCONN);
696
697 rsp.dcid = cpu_to_le16(chan->scid);
698 rsp.mtu = cpu_to_le16(chan->imtu);
699 rsp.mps = cpu_to_le16(chan->mps);
700 rsp.credits = cpu_to_le16(chan->rx_credits);
701 rsp.result = cpu_to_le16(result);
702
703 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CONN_RSP, sizeof(rsp),
704 &rsp);
705 }
706
707 static void l2cap_chan_connect_reject(struct l2cap_chan *chan)
708 {
709 struct l2cap_conn *conn = chan->conn;
710 struct l2cap_conn_rsp rsp;
711 u16 result;
712
713 if (test_bit(FLAG_DEFER_SETUP, &chan->flags))
714 result = L2CAP_CR_SEC_BLOCK;
715 else
716 result = L2CAP_CR_BAD_PSM;
717
718 l2cap_state_change(chan, BT_DISCONN);
719
720 rsp.scid = cpu_to_le16(chan->dcid);
721 rsp.dcid = cpu_to_le16(chan->scid);
722 rsp.result = cpu_to_le16(result);
723 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
724
725 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP, sizeof(rsp), &rsp);
726 }
727
728 void l2cap_chan_close(struct l2cap_chan *chan, int reason)
729 {
730 struct l2cap_conn *conn = chan->conn;
731
732 BT_DBG("chan %p state %s", chan, state_to_string(chan->state));
733
734 switch (chan->state) {
735 case BT_LISTEN:
736 chan->ops->teardown(chan, 0);
737 break;
738
739 case BT_CONNECTED:
740 case BT_CONFIG:
741 if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED) {
742 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
743 l2cap_send_disconn_req(chan, reason);
744 } else
745 l2cap_chan_del(chan, reason);
746 break;
747
748 case BT_CONNECT2:
749 if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED) {
750 if (conn->hcon->type == ACL_LINK)
751 l2cap_chan_connect_reject(chan);
752 else if (conn->hcon->type == LE_LINK)
753 l2cap_chan_le_connect_reject(chan);
754 }
755
756 l2cap_chan_del(chan, reason);
757 break;
758
759 case BT_CONNECT:
760 case BT_DISCONN:
761 l2cap_chan_del(chan, reason);
762 break;
763
764 default:
765 chan->ops->teardown(chan, 0);
766 break;
767 }
768 }
769 EXPORT_SYMBOL(l2cap_chan_close);
770
771 static inline u8 l2cap_get_auth_type(struct l2cap_chan *chan)
772 {
773 switch (chan->chan_type) {
774 case L2CAP_CHAN_RAW:
775 switch (chan->sec_level) {
776 case BT_SECURITY_HIGH:
777 case BT_SECURITY_FIPS:
778 return HCI_AT_DEDICATED_BONDING_MITM;
779 case BT_SECURITY_MEDIUM:
780 return HCI_AT_DEDICATED_BONDING;
781 default:
782 return HCI_AT_NO_BONDING;
783 }
784 break;
785 case L2CAP_CHAN_CONN_LESS:
786 if (chan->psm == cpu_to_le16(L2CAP_PSM_3DSP)) {
787 if (chan->sec_level == BT_SECURITY_LOW)
788 chan->sec_level = BT_SECURITY_SDP;
789 }
790 if (chan->sec_level == BT_SECURITY_HIGH ||
791 chan->sec_level == BT_SECURITY_FIPS)
792 return HCI_AT_NO_BONDING_MITM;
793 else
794 return HCI_AT_NO_BONDING;
795 break;
796 case L2CAP_CHAN_CONN_ORIENTED:
797 if (chan->psm == cpu_to_le16(L2CAP_PSM_SDP)) {
798 if (chan->sec_level == BT_SECURITY_LOW)
799 chan->sec_level = BT_SECURITY_SDP;
800
801 if (chan->sec_level == BT_SECURITY_HIGH ||
802 chan->sec_level == BT_SECURITY_FIPS)
803 return HCI_AT_NO_BONDING_MITM;
804 else
805 return HCI_AT_NO_BONDING;
806 }
807 /* fall through */
808 default:
809 switch (chan->sec_level) {
810 case BT_SECURITY_HIGH:
811 case BT_SECURITY_FIPS:
812 return HCI_AT_GENERAL_BONDING_MITM;
813 case BT_SECURITY_MEDIUM:
814 return HCI_AT_GENERAL_BONDING;
815 default:
816 return HCI_AT_NO_BONDING;
817 }
818 break;
819 }
820 }
821
822 /* Service level security */
823 int l2cap_chan_check_security(struct l2cap_chan *chan, bool initiator)
824 {
825 struct l2cap_conn *conn = chan->conn;
826 __u8 auth_type;
827
828 if (conn->hcon->type == LE_LINK)
829 return smp_conn_security(conn->hcon, chan->sec_level);
830
831 auth_type = l2cap_get_auth_type(chan);
832
833 return hci_conn_security(conn->hcon, chan->sec_level, auth_type,
834 initiator);
835 }
836
837 static u8 l2cap_get_ident(struct l2cap_conn *conn)
838 {
839 u8 id;
840
841 /* Get next available identificator.
842 * 1 - 128 are used by kernel.
843 * 129 - 199 are reserved.
844 * 200 - 254 are used by utilities like l2ping, etc.
845 */
846
847 mutex_lock(&conn->ident_lock);
848
849 if (++conn->tx_ident > 128)
850 conn->tx_ident = 1;
851
852 id = conn->tx_ident;
853
854 mutex_unlock(&conn->ident_lock);
855
856 return id;
857 }
858
859 static void l2cap_send_cmd(struct l2cap_conn *conn, u8 ident, u8 code, u16 len,
860 void *data)
861 {
862 struct sk_buff *skb = l2cap_build_cmd(conn, code, ident, len, data);
863 u8 flags;
864
865 BT_DBG("code 0x%2.2x", code);
866
867 if (!skb)
868 return;
869
870 /* Use NO_FLUSH if supported or we have an LE link (which does
871 * not support auto-flushing packets) */
872 if (lmp_no_flush_capable(conn->hcon->hdev) ||
873 conn->hcon->type == LE_LINK)
874 flags = ACL_START_NO_FLUSH;
875 else
876 flags = ACL_START;
877
878 bt_cb(skb)->force_active = BT_POWER_FORCE_ACTIVE_ON;
879 skb->priority = HCI_PRIO_MAX;
880
881 hci_send_acl(conn->hchan, skb, flags);
882 }
883
884 static bool __chan_is_moving(struct l2cap_chan *chan)
885 {
886 return chan->move_state != L2CAP_MOVE_STABLE &&
887 chan->move_state != L2CAP_MOVE_WAIT_PREPARE;
888 }
889
890 static void l2cap_do_send(struct l2cap_chan *chan, struct sk_buff *skb)
891 {
892 struct hci_conn *hcon = chan->conn->hcon;
893 u16 flags;
894
895 BT_DBG("chan %p, skb %p len %d priority %u", chan, skb, skb->len,
896 skb->priority);
897
898 if (chan->hs_hcon && !__chan_is_moving(chan)) {
899 if (chan->hs_hchan)
900 hci_send_acl(chan->hs_hchan, skb, ACL_COMPLETE);
901 else
902 kfree_skb(skb);
903
904 return;
905 }
906
907 /* Use NO_FLUSH for LE links (where this is the only option) or
908 * if the BR/EDR link supports it and flushing has not been
909 * explicitly requested (through FLAG_FLUSHABLE).
910 */
911 if (hcon->type == LE_LINK ||
912 (!test_bit(FLAG_FLUSHABLE, &chan->flags) &&
913 lmp_no_flush_capable(hcon->hdev)))
914 flags = ACL_START_NO_FLUSH;
915 else
916 flags = ACL_START;
917
918 bt_cb(skb)->force_active = test_bit(FLAG_FORCE_ACTIVE, &chan->flags);
919 hci_send_acl(chan->conn->hchan, skb, flags);
920 }
921
922 static void __unpack_enhanced_control(u16 enh, struct l2cap_ctrl *control)
923 {
924 control->reqseq = (enh & L2CAP_CTRL_REQSEQ) >> L2CAP_CTRL_REQSEQ_SHIFT;
925 control->final = (enh & L2CAP_CTRL_FINAL) >> L2CAP_CTRL_FINAL_SHIFT;
926
927 if (enh & L2CAP_CTRL_FRAME_TYPE) {
928 /* S-Frame */
929 control->sframe = 1;
930 control->poll = (enh & L2CAP_CTRL_POLL) >> L2CAP_CTRL_POLL_SHIFT;
931 control->super = (enh & L2CAP_CTRL_SUPERVISE) >> L2CAP_CTRL_SUPER_SHIFT;
932
933 control->sar = 0;
934 control->txseq = 0;
935 } else {
936 /* I-Frame */
937 control->sframe = 0;
938 control->sar = (enh & L2CAP_CTRL_SAR) >> L2CAP_CTRL_SAR_SHIFT;
939 control->txseq = (enh & L2CAP_CTRL_TXSEQ) >> L2CAP_CTRL_TXSEQ_SHIFT;
940
941 control->poll = 0;
942 control->super = 0;
943 }
944 }
945
946 static void __unpack_extended_control(u32 ext, struct l2cap_ctrl *control)
947 {
948 control->reqseq = (ext & L2CAP_EXT_CTRL_REQSEQ) >> L2CAP_EXT_CTRL_REQSEQ_SHIFT;
949 control->final = (ext & L2CAP_EXT_CTRL_FINAL) >> L2CAP_EXT_CTRL_FINAL_SHIFT;
950
951 if (ext & L2CAP_EXT_CTRL_FRAME_TYPE) {
952 /* S-Frame */
953 control->sframe = 1;
954 control->poll = (ext & L2CAP_EXT_CTRL_POLL) >> L2CAP_EXT_CTRL_POLL_SHIFT;
955 control->super = (ext & L2CAP_EXT_CTRL_SUPERVISE) >> L2CAP_EXT_CTRL_SUPER_SHIFT;
956
957 control->sar = 0;
958 control->txseq = 0;
959 } else {
960 /* I-Frame */
961 control->sframe = 0;
962 control->sar = (ext & L2CAP_EXT_CTRL_SAR) >> L2CAP_EXT_CTRL_SAR_SHIFT;
963 control->txseq = (ext & L2CAP_EXT_CTRL_TXSEQ) >> L2CAP_EXT_CTRL_TXSEQ_SHIFT;
964
965 control->poll = 0;
966 control->super = 0;
967 }
968 }
969
970 static inline void __unpack_control(struct l2cap_chan *chan,
971 struct sk_buff *skb)
972 {
973 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) {
974 __unpack_extended_control(get_unaligned_le32(skb->data),
975 &bt_cb(skb)->l2cap);
976 skb_pull(skb, L2CAP_EXT_CTRL_SIZE);
977 } else {
978 __unpack_enhanced_control(get_unaligned_le16(skb->data),
979 &bt_cb(skb)->l2cap);
980 skb_pull(skb, L2CAP_ENH_CTRL_SIZE);
981 }
982 }
983
984 static u32 __pack_extended_control(struct l2cap_ctrl *control)
985 {
986 u32 packed;
987
988 packed = control->reqseq << L2CAP_EXT_CTRL_REQSEQ_SHIFT;
989 packed |= control->final << L2CAP_EXT_CTRL_FINAL_SHIFT;
990
991 if (control->sframe) {
992 packed |= control->poll << L2CAP_EXT_CTRL_POLL_SHIFT;
993 packed |= control->super << L2CAP_EXT_CTRL_SUPER_SHIFT;
994 packed |= L2CAP_EXT_CTRL_FRAME_TYPE;
995 } else {
996 packed |= control->sar << L2CAP_EXT_CTRL_SAR_SHIFT;
997 packed |= control->txseq << L2CAP_EXT_CTRL_TXSEQ_SHIFT;
998 }
999
1000 return packed;
1001 }
1002
1003 static u16 __pack_enhanced_control(struct l2cap_ctrl *control)
1004 {
1005 u16 packed;
1006
1007 packed = control->reqseq << L2CAP_CTRL_REQSEQ_SHIFT;
1008 packed |= control->final << L2CAP_CTRL_FINAL_SHIFT;
1009
1010 if (control->sframe) {
1011 packed |= control->poll << L2CAP_CTRL_POLL_SHIFT;
1012 packed |= control->super << L2CAP_CTRL_SUPER_SHIFT;
1013 packed |= L2CAP_CTRL_FRAME_TYPE;
1014 } else {
1015 packed |= control->sar << L2CAP_CTRL_SAR_SHIFT;
1016 packed |= control->txseq << L2CAP_CTRL_TXSEQ_SHIFT;
1017 }
1018
1019 return packed;
1020 }
1021
1022 static inline void __pack_control(struct l2cap_chan *chan,
1023 struct l2cap_ctrl *control,
1024 struct sk_buff *skb)
1025 {
1026 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) {
1027 put_unaligned_le32(__pack_extended_control(control),
1028 skb->data + L2CAP_HDR_SIZE);
1029 } else {
1030 put_unaligned_le16(__pack_enhanced_control(control),
1031 skb->data + L2CAP_HDR_SIZE);
1032 }
1033 }
1034
1035 static inline unsigned int __ertm_hdr_size(struct l2cap_chan *chan)
1036 {
1037 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
1038 return L2CAP_EXT_HDR_SIZE;
1039 else
1040 return L2CAP_ENH_HDR_SIZE;
1041 }
1042
1043 static struct sk_buff *l2cap_create_sframe_pdu(struct l2cap_chan *chan,
1044 u32 control)
1045 {
1046 struct sk_buff *skb;
1047 struct l2cap_hdr *lh;
1048 int hlen = __ertm_hdr_size(chan);
1049
1050 if (chan->fcs == L2CAP_FCS_CRC16)
1051 hlen += L2CAP_FCS_SIZE;
1052
1053 skb = bt_skb_alloc(hlen, GFP_KERNEL);
1054
1055 if (!skb)
1056 return ERR_PTR(-ENOMEM);
1057
1058 lh = skb_put(skb, L2CAP_HDR_SIZE);
1059 lh->len = cpu_to_le16(hlen - L2CAP_HDR_SIZE);
1060 lh->cid = cpu_to_le16(chan->dcid);
1061
1062 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
1063 put_unaligned_le32(control, skb_put(skb, L2CAP_EXT_CTRL_SIZE));
1064 else
1065 put_unaligned_le16(control, skb_put(skb, L2CAP_ENH_CTRL_SIZE));
1066
1067 if (chan->fcs == L2CAP_FCS_CRC16) {
1068 u16 fcs = crc16(0, (u8 *)skb->data, skb->len);
1069 put_unaligned_le16(fcs, skb_put(skb, L2CAP_FCS_SIZE));
1070 }
1071
1072 skb->priority = HCI_PRIO_MAX;
1073 return skb;
1074 }
1075
1076 static void l2cap_send_sframe(struct l2cap_chan *chan,
1077 struct l2cap_ctrl *control)
1078 {
1079 struct sk_buff *skb;
1080 u32 control_field;
1081
1082 BT_DBG("chan %p, control %p", chan, control);
1083
1084 if (!control->sframe)
1085 return;
1086
1087 if (__chan_is_moving(chan))
1088 return;
1089
1090 if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state) &&
1091 !control->poll)
1092 control->final = 1;
1093
1094 if (control->super == L2CAP_SUPER_RR)
1095 clear_bit(CONN_RNR_SENT, &chan->conn_state);
1096 else if (control->super == L2CAP_SUPER_RNR)
1097 set_bit(CONN_RNR_SENT, &chan->conn_state);
1098
1099 if (control->super != L2CAP_SUPER_SREJ) {
1100 chan->last_acked_seq = control->reqseq;
1101 __clear_ack_timer(chan);
1102 }
1103
1104 BT_DBG("reqseq %d, final %d, poll %d, super %d", control->reqseq,
1105 control->final, control->poll, control->super);
1106
1107 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
1108 control_field = __pack_extended_control(control);
1109 else
1110 control_field = __pack_enhanced_control(control);
1111
1112 skb = l2cap_create_sframe_pdu(chan, control_field);
1113 if (!IS_ERR(skb))
1114 l2cap_do_send(chan, skb);
1115 }
1116
1117 static void l2cap_send_rr_or_rnr(struct l2cap_chan *chan, bool poll)
1118 {
1119 struct l2cap_ctrl control;
1120
1121 BT_DBG("chan %p, poll %d", chan, poll);
1122
1123 memset(&control, 0, sizeof(control));
1124 control.sframe = 1;
1125 control.poll = poll;
1126
1127 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state))
1128 control.super = L2CAP_SUPER_RNR;
1129 else
1130 control.super = L2CAP_SUPER_RR;
1131
1132 control.reqseq = chan->buffer_seq;
1133 l2cap_send_sframe(chan, &control);
1134 }
1135
1136 static inline int __l2cap_no_conn_pending(struct l2cap_chan *chan)
1137 {
1138 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED)
1139 return true;
1140
1141 return !test_bit(CONF_CONNECT_PEND, &chan->conf_state);
1142 }
1143
1144 static bool __amp_capable(struct l2cap_chan *chan)
1145 {
1146 struct l2cap_conn *conn = chan->conn;
1147 struct hci_dev *hdev;
1148 bool amp_available = false;
1149
1150 if (!(conn->local_fixed_chan & L2CAP_FC_A2MP))
1151 return false;
1152
1153 if (!(conn->remote_fixed_chan & L2CAP_FC_A2MP))
1154 return false;
1155
1156 read_lock(&hci_dev_list_lock);
1157 list_for_each_entry(hdev, &hci_dev_list, list) {
1158 if (hdev->amp_type != AMP_TYPE_BREDR &&
1159 test_bit(HCI_UP, &hdev->flags)) {
1160 amp_available = true;
1161 break;
1162 }
1163 }
1164 read_unlock(&hci_dev_list_lock);
1165
1166 if (chan->chan_policy == BT_CHANNEL_POLICY_AMP_PREFERRED)
1167 return amp_available;
1168
1169 return false;
1170 }
1171
1172 static bool l2cap_check_efs(struct l2cap_chan *chan)
1173 {
1174 /* Check EFS parameters */
1175 return true;
1176 }
1177
1178 void l2cap_send_conn_req(struct l2cap_chan *chan)
1179 {
1180 struct l2cap_conn *conn = chan->conn;
1181 struct l2cap_conn_req req;
1182
1183 req.scid = cpu_to_le16(chan->scid);
1184 req.psm = chan->psm;
1185
1186 chan->ident = l2cap_get_ident(conn);
1187
1188 set_bit(CONF_CONNECT_PEND, &chan->conf_state);
1189
1190 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_REQ, sizeof(req), &req);
1191 }
1192
1193 static void l2cap_send_create_chan_req(struct l2cap_chan *chan, u8 amp_id)
1194 {
1195 struct l2cap_create_chan_req req;
1196 req.scid = cpu_to_le16(chan->scid);
1197 req.psm = chan->psm;
1198 req.amp_id = amp_id;
1199
1200 chan->ident = l2cap_get_ident(chan->conn);
1201
1202 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_CREATE_CHAN_REQ,
1203 sizeof(req), &req);
1204 }
1205
1206 static void l2cap_move_setup(struct l2cap_chan *chan)
1207 {
1208 struct sk_buff *skb;
1209
1210 BT_DBG("chan %p", chan);
1211
1212 if (chan->mode != L2CAP_MODE_ERTM)
1213 return;
1214
1215 __clear_retrans_timer(chan);
1216 __clear_monitor_timer(chan);
1217 __clear_ack_timer(chan);
1218
1219 chan->retry_count = 0;
1220 skb_queue_walk(&chan->tx_q, skb) {
1221 if (bt_cb(skb)->l2cap.retries)
1222 bt_cb(skb)->l2cap.retries = 1;
1223 else
1224 break;
1225 }
1226
1227 chan->expected_tx_seq = chan->buffer_seq;
1228
1229 clear_bit(CONN_REJ_ACT, &chan->conn_state);
1230 clear_bit(CONN_SREJ_ACT, &chan->conn_state);
1231 l2cap_seq_list_clear(&chan->retrans_list);
1232 l2cap_seq_list_clear(&chan->srej_list);
1233 skb_queue_purge(&chan->srej_q);
1234
1235 chan->tx_state = L2CAP_TX_STATE_XMIT;
1236 chan->rx_state = L2CAP_RX_STATE_MOVE;
1237
1238 set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
1239 }
1240
1241 static void l2cap_move_done(struct l2cap_chan *chan)
1242 {
1243 u8 move_role = chan->move_role;
1244 BT_DBG("chan %p", chan);
1245
1246 chan->move_state = L2CAP_MOVE_STABLE;
1247 chan->move_role = L2CAP_MOVE_ROLE_NONE;
1248
1249 if (chan->mode != L2CAP_MODE_ERTM)
1250 return;
1251
1252 switch (move_role) {
1253 case L2CAP_MOVE_ROLE_INITIATOR:
1254 l2cap_tx(chan, NULL, NULL, L2CAP_EV_EXPLICIT_POLL);
1255 chan->rx_state = L2CAP_RX_STATE_WAIT_F;
1256 break;
1257 case L2CAP_MOVE_ROLE_RESPONDER:
1258 chan->rx_state = L2CAP_RX_STATE_WAIT_P;
1259 break;
1260 }
1261 }
1262
1263 static void l2cap_chan_ready(struct l2cap_chan *chan)
1264 {
1265 /* The channel may have already been flagged as connected in
1266 * case of receiving data before the L2CAP info req/rsp
1267 * procedure is complete.
1268 */
1269 if (chan->state == BT_CONNECTED)
1270 return;
1271
1272 /* This clears all conf flags, including CONF_NOT_COMPLETE */
1273 chan->conf_state = 0;
1274 __clear_chan_timer(chan);
1275
1276 if (chan->mode == L2CAP_MODE_LE_FLOWCTL && !chan->tx_credits)
1277 chan->ops->suspend(chan);
1278
1279 chan->state = BT_CONNECTED;
1280
1281 chan->ops->ready(chan);
1282 }
1283
1284 static void l2cap_le_connect(struct l2cap_chan *chan)
1285 {
1286 struct l2cap_conn *conn = chan->conn;
1287 struct l2cap_le_conn_req req;
1288
1289 if (test_and_set_bit(FLAG_LE_CONN_REQ_SENT, &chan->flags))
1290 return;
1291
1292 l2cap_le_flowctl_init(chan, 0);
1293
1294 req.psm = chan->psm;
1295 req.scid = cpu_to_le16(chan->scid);
1296 req.mtu = cpu_to_le16(chan->imtu);
1297 req.mps = cpu_to_le16(chan->mps);
1298 req.credits = cpu_to_le16(chan->rx_credits);
1299
1300 chan->ident = l2cap_get_ident(conn);
1301
1302 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CONN_REQ,
1303 sizeof(req), &req);
1304 }
1305
1306 static void l2cap_le_start(struct l2cap_chan *chan)
1307 {
1308 struct l2cap_conn *conn = chan->conn;
1309
1310 if (!smp_conn_security(conn->hcon, chan->sec_level))
1311 return;
1312
1313 if (!chan->psm) {
1314 l2cap_chan_ready(chan);
1315 return;
1316 }
1317
1318 if (chan->state == BT_CONNECT)
1319 l2cap_le_connect(chan);
1320 }
1321
1322 static void l2cap_start_connection(struct l2cap_chan *chan)
1323 {
1324 if (__amp_capable(chan)) {
1325 BT_DBG("chan %p AMP capable: discover AMPs", chan);
1326 a2mp_discover_amp(chan);
1327 } else if (chan->conn->hcon->type == LE_LINK) {
1328 l2cap_le_start(chan);
1329 } else {
1330 l2cap_send_conn_req(chan);
1331 }
1332 }
1333
1334 static void l2cap_request_info(struct l2cap_conn *conn)
1335 {
1336 struct l2cap_info_req req;
1337
1338 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT)
1339 return;
1340
1341 req.type = cpu_to_le16(L2CAP_IT_FEAT_MASK);
1342
1343 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_SENT;
1344 conn->info_ident = l2cap_get_ident(conn);
1345
1346 schedule_delayed_work(&conn->info_timer, L2CAP_INFO_TIMEOUT);
1347
1348 l2cap_send_cmd(conn, conn->info_ident, L2CAP_INFO_REQ,
1349 sizeof(req), &req);
1350 }
1351
1352 static bool l2cap_check_enc_key_size(struct hci_conn *hcon)
1353 {
1354 /* The minimum encryption key size needs to be enforced by the
1355 * host stack before establishing any L2CAP connections. The
1356 * specification in theory allows a minimum of 1, but to align
1357 * BR/EDR and LE transports, a minimum of 7 is chosen.
1358 *
1359 * This check might also be called for unencrypted connections
1360 * that have no key size requirements. Ensure that the link is
1361 * actually encrypted before enforcing a key size.
1362 */
1363 return (!test_bit(HCI_CONN_ENCRYPT, &hcon->flags) ||
1364 hcon->enc_key_size >= hcon->hdev->min_enc_key_size);
1365 }
1366
1367 static void l2cap_do_start(struct l2cap_chan *chan)
1368 {
1369 struct l2cap_conn *conn = chan->conn;
1370
1371 if (conn->hcon->type == LE_LINK) {
1372 l2cap_le_start(chan);
1373 return;
1374 }
1375
1376 if (!(conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT)) {
1377 l2cap_request_info(conn);
1378 return;
1379 }
1380
1381 if (!(conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE))
1382 return;
1383
1384 if (!l2cap_chan_check_security(chan, true) ||
1385 !__l2cap_no_conn_pending(chan))
1386 return;
1387
1388 if (l2cap_check_enc_key_size(conn->hcon))
1389 l2cap_start_connection(chan);
1390 else
1391 __set_chan_timer(chan, L2CAP_DISC_TIMEOUT);
1392 }
1393
1394 static inline int l2cap_mode_supported(__u8 mode, __u32 feat_mask)
1395 {
1396 u32 local_feat_mask = l2cap_feat_mask;
1397 if (!disable_ertm)
1398 local_feat_mask |= L2CAP_FEAT_ERTM | L2CAP_FEAT_STREAMING;
1399
1400 switch (mode) {
1401 case L2CAP_MODE_ERTM:
1402 return L2CAP_FEAT_ERTM & feat_mask & local_feat_mask;
1403 case L2CAP_MODE_STREAMING:
1404 return L2CAP_FEAT_STREAMING & feat_mask & local_feat_mask;
1405 default:
1406 return 0x00;
1407 }
1408 }
1409
1410 static void l2cap_send_disconn_req(struct l2cap_chan *chan, int err)
1411 {
1412 struct l2cap_conn *conn = chan->conn;
1413 struct l2cap_disconn_req req;
1414
1415 if (!conn)
1416 return;
1417
1418 if (chan->mode == L2CAP_MODE_ERTM && chan->state == BT_CONNECTED) {
1419 __clear_retrans_timer(chan);
1420 __clear_monitor_timer(chan);
1421 __clear_ack_timer(chan);
1422 }
1423
1424 if (chan->scid == L2CAP_CID_A2MP) {
1425 l2cap_state_change(chan, BT_DISCONN);
1426 return;
1427 }
1428
1429 req.dcid = cpu_to_le16(chan->dcid);
1430 req.scid = cpu_to_le16(chan->scid);
1431 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_DISCONN_REQ,
1432 sizeof(req), &req);
1433
1434 l2cap_state_change_and_error(chan, BT_DISCONN, err);
1435 }
1436
1437 /* ---- L2CAP connections ---- */
1438 static void l2cap_conn_start(struct l2cap_conn *conn)
1439 {
1440 struct l2cap_chan *chan, *tmp;
1441
1442 BT_DBG("conn %p", conn);
1443
1444 mutex_lock(&conn->chan_lock);
1445
1446 list_for_each_entry_safe(chan, tmp, &conn->chan_l, list) {
1447 l2cap_chan_lock(chan);
1448
1449 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
1450 l2cap_chan_ready(chan);
1451 l2cap_chan_unlock(chan);
1452 continue;
1453 }
1454
1455 if (chan->state == BT_CONNECT) {
1456 if (!l2cap_chan_check_security(chan, true) ||
1457 !__l2cap_no_conn_pending(chan)) {
1458 l2cap_chan_unlock(chan);
1459 continue;
1460 }
1461
1462 if (!l2cap_mode_supported(chan->mode, conn->feat_mask)
1463 && test_bit(CONF_STATE2_DEVICE,
1464 &chan->conf_state)) {
1465 l2cap_chan_close(chan, ECONNRESET);
1466 l2cap_chan_unlock(chan);
1467 continue;
1468 }
1469
1470 if (l2cap_check_enc_key_size(conn->hcon))
1471 l2cap_start_connection(chan);
1472 else
1473 l2cap_chan_close(chan, ECONNREFUSED);
1474
1475 } else if (chan->state == BT_CONNECT2) {
1476 struct l2cap_conn_rsp rsp;
1477 char buf[128];
1478 rsp.scid = cpu_to_le16(chan->dcid);
1479 rsp.dcid = cpu_to_le16(chan->scid);
1480
1481 if (l2cap_chan_check_security(chan, false)) {
1482 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
1483 rsp.result = cpu_to_le16(L2CAP_CR_PEND);
1484 rsp.status = cpu_to_le16(L2CAP_CS_AUTHOR_PEND);
1485 chan->ops->defer(chan);
1486
1487 } else {
1488 l2cap_state_change(chan, BT_CONFIG);
1489 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
1490 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
1491 }
1492 } else {
1493 rsp.result = cpu_to_le16(L2CAP_CR_PEND);
1494 rsp.status = cpu_to_le16(L2CAP_CS_AUTHEN_PEND);
1495 }
1496
1497 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP,
1498 sizeof(rsp), &rsp);
1499
1500 if (test_bit(CONF_REQ_SENT, &chan->conf_state) ||
1501 rsp.result != L2CAP_CR_SUCCESS) {
1502 l2cap_chan_unlock(chan);
1503 continue;
1504 }
1505
1506 set_bit(CONF_REQ_SENT, &chan->conf_state);
1507 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
1508 l2cap_build_conf_req(chan, buf, sizeof(buf)), buf);
1509 chan->num_conf_req++;
1510 }
1511
1512 l2cap_chan_unlock(chan);
1513 }
1514
1515 mutex_unlock(&conn->chan_lock);
1516 }
1517
1518 static void l2cap_le_conn_ready(struct l2cap_conn *conn)
1519 {
1520 struct hci_conn *hcon = conn->hcon;
1521 struct hci_dev *hdev = hcon->hdev;
1522
1523 BT_DBG("%s conn %p", hdev->name, conn);
1524
1525 /* For outgoing pairing which doesn't necessarily have an
1526 * associated socket (e.g. mgmt_pair_device).
1527 */
1528 if (hcon->out)
1529 smp_conn_security(hcon, hcon->pending_sec_level);
1530
1531 /* For LE slave connections, make sure the connection interval
1532 * is in the range of the minium and maximum interval that has
1533 * been configured for this connection. If not, then trigger
1534 * the connection update procedure.
1535 */
1536 if (hcon->role == HCI_ROLE_SLAVE &&
1537 (hcon->le_conn_interval < hcon->le_conn_min_interval ||
1538 hcon->le_conn_interval > hcon->le_conn_max_interval)) {
1539 struct l2cap_conn_param_update_req req;
1540
1541 req.min = cpu_to_le16(hcon->le_conn_min_interval);
1542 req.max = cpu_to_le16(hcon->le_conn_max_interval);
1543 req.latency = cpu_to_le16(hcon->le_conn_latency);
1544 req.to_multiplier = cpu_to_le16(hcon->le_supv_timeout);
1545
1546 l2cap_send_cmd(conn, l2cap_get_ident(conn),
1547 L2CAP_CONN_PARAM_UPDATE_REQ, sizeof(req), &req);
1548 }
1549 }
1550
1551 static void l2cap_conn_ready(struct l2cap_conn *conn)
1552 {
1553 struct l2cap_chan *chan;
1554 struct hci_conn *hcon = conn->hcon;
1555
1556 BT_DBG("conn %p", conn);
1557
1558 if (hcon->type == ACL_LINK)
1559 l2cap_request_info(conn);
1560
1561 mutex_lock(&conn->chan_lock);
1562
1563 list_for_each_entry(chan, &conn->chan_l, list) {
1564
1565 l2cap_chan_lock(chan);
1566
1567 if (chan->scid == L2CAP_CID_A2MP) {
1568 l2cap_chan_unlock(chan);
1569 continue;
1570 }
1571
1572 if (hcon->type == LE_LINK) {
1573 l2cap_le_start(chan);
1574 } else if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
1575 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE)
1576 l2cap_chan_ready(chan);
1577 } else if (chan->state == BT_CONNECT) {
1578 l2cap_do_start(chan);
1579 }
1580
1581 l2cap_chan_unlock(chan);
1582 }
1583
1584 mutex_unlock(&conn->chan_lock);
1585
1586 if (hcon->type == LE_LINK)
1587 l2cap_le_conn_ready(conn);
1588
1589 queue_work(hcon->hdev->workqueue, &conn->pending_rx_work);
1590 }
1591
1592 /* Notify sockets that we cannot guaranty reliability anymore */
1593 static void l2cap_conn_unreliable(struct l2cap_conn *conn, int err)
1594 {
1595 struct l2cap_chan *chan;
1596
1597 BT_DBG("conn %p", conn);
1598
1599 mutex_lock(&conn->chan_lock);
1600
1601 list_for_each_entry(chan, &conn->chan_l, list) {
1602 if (test_bit(FLAG_FORCE_RELIABLE, &chan->flags))
1603 l2cap_chan_set_err(chan, err);
1604 }
1605
1606 mutex_unlock(&conn->chan_lock);
1607 }
1608
1609 static void l2cap_info_timeout(struct work_struct *work)
1610 {
1611 struct l2cap_conn *conn = container_of(work, struct l2cap_conn,
1612 info_timer.work);
1613
1614 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
1615 conn->info_ident = 0;
1616
1617 l2cap_conn_start(conn);
1618 }
1619
1620 /*
1621 * l2cap_user
1622 * External modules can register l2cap_user objects on l2cap_conn. The ->probe
1623 * callback is called during registration. The ->remove callback is called
1624 * during unregistration.
1625 * An l2cap_user object can either be explicitly unregistered or when the
1626 * underlying l2cap_conn object is deleted. This guarantees that l2cap->hcon,
1627 * l2cap->hchan, .. are valid as long as the remove callback hasn't been called.
1628 * External modules must own a reference to the l2cap_conn object if they intend
1629 * to call l2cap_unregister_user(). The l2cap_conn object might get destroyed at
1630 * any time if they don't.
1631 */
1632
1633 int l2cap_register_user(struct l2cap_conn *conn, struct l2cap_user *user)
1634 {
1635 struct hci_dev *hdev = conn->hcon->hdev;
1636 int ret;
1637
1638 /* We need to check whether l2cap_conn is registered. If it is not, we
1639 * must not register the l2cap_user. l2cap_conn_del() is unregisters
1640 * l2cap_conn objects, but doesn't provide its own locking. Instead, it
1641 * relies on the parent hci_conn object to be locked. This itself relies
1642 * on the hci_dev object to be locked. So we must lock the hci device
1643 * here, too. */
1644
1645 hci_dev_lock(hdev);
1646
1647 if (!list_empty(&user->list)) {
1648 ret = -EINVAL;
1649 goto out_unlock;
1650 }
1651
1652 /* conn->hchan is NULL after l2cap_conn_del() was called */
1653 if (!conn->hchan) {
1654 ret = -ENODEV;
1655 goto out_unlock;
1656 }
1657
1658 ret = user->probe(conn, user);
1659 if (ret)
1660 goto out_unlock;
1661
1662 list_add(&user->list, &conn->users);
1663 ret = 0;
1664
1665 out_unlock:
1666 hci_dev_unlock(hdev);
1667 return ret;
1668 }
1669 EXPORT_SYMBOL(l2cap_register_user);
1670
1671 void l2cap_unregister_user(struct l2cap_conn *conn, struct l2cap_user *user)
1672 {
1673 struct hci_dev *hdev = conn->hcon->hdev;
1674
1675 hci_dev_lock(hdev);
1676
1677 if (list_empty(&user->list))
1678 goto out_unlock;
1679
1680 list_del_init(&user->list);
1681 user->remove(conn, user);
1682
1683 out_unlock:
1684 hci_dev_unlock(hdev);
1685 }
1686 EXPORT_SYMBOL(l2cap_unregister_user);
1687
1688 static void l2cap_unregister_all_users(struct l2cap_conn *conn)
1689 {
1690 struct l2cap_user *user;
1691
1692 while (!list_empty(&conn->users)) {
1693 user = list_first_entry(&conn->users, struct l2cap_user, list);
1694 list_del_init(&user->list);
1695 user->remove(conn, user);
1696 }
1697 }
1698
1699 static void l2cap_conn_del(struct hci_conn *hcon, int err)
1700 {
1701 struct l2cap_conn *conn = hcon->l2cap_data;
1702 struct l2cap_chan *chan, *l;
1703
1704 if (!conn)
1705 return;
1706
1707 BT_DBG("hcon %p conn %p, err %d", hcon, conn, err);
1708
1709 kfree_skb(conn->rx_skb);
1710
1711 skb_queue_purge(&conn->pending_rx);
1712
1713 /* We can not call flush_work(&conn->pending_rx_work) here since we
1714 * might block if we are running on a worker from the same workqueue
1715 * pending_rx_work is waiting on.
1716 */
1717 if (work_pending(&conn->pending_rx_work))
1718 cancel_work_sync(&conn->pending_rx_work);
1719
1720 if (work_pending(&conn->id_addr_update_work))
1721 cancel_work_sync(&conn->id_addr_update_work);
1722
1723 l2cap_unregister_all_users(conn);
1724
1725 /* Force the connection to be immediately dropped */
1726 hcon->disc_timeout = 0;
1727
1728 mutex_lock(&conn->chan_lock);
1729
1730 /* Kill channels */
1731 list_for_each_entry_safe(chan, l, &conn->chan_l, list) {
1732 l2cap_chan_hold(chan);
1733 l2cap_chan_lock(chan);
1734
1735 l2cap_chan_del(chan, err);
1736
1737 l2cap_chan_unlock(chan);
1738
1739 chan->ops->close(chan);
1740 l2cap_chan_put(chan);
1741 }
1742
1743 mutex_unlock(&conn->chan_lock);
1744
1745 hci_chan_del(conn->hchan);
1746
1747 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT)
1748 cancel_delayed_work_sync(&conn->info_timer);
1749
1750 hcon->l2cap_data = NULL;
1751 conn->hchan = NULL;
1752 l2cap_conn_put(conn);
1753 }
1754
1755 static void l2cap_conn_free(struct kref *ref)
1756 {
1757 struct l2cap_conn *conn = container_of(ref, struct l2cap_conn, ref);
1758
1759 hci_conn_put(conn->hcon);
1760 kfree(conn);
1761 }
1762
1763 struct l2cap_conn *l2cap_conn_get(struct l2cap_conn *conn)
1764 {
1765 kref_get(&conn->ref);
1766 return conn;
1767 }
1768 EXPORT_SYMBOL(l2cap_conn_get);
1769
1770 void l2cap_conn_put(struct l2cap_conn *conn)
1771 {
1772 kref_put(&conn->ref, l2cap_conn_free);
1773 }
1774 EXPORT_SYMBOL(l2cap_conn_put);
1775
1776 /* ---- Socket interface ---- */
1777
1778 /* Find socket with psm and source / destination bdaddr.
1779 * Returns closest match.
1780 */
1781 static struct l2cap_chan *l2cap_global_chan_by_psm(int state, __le16 psm,
1782 bdaddr_t *src,
1783 bdaddr_t *dst,
1784 u8 link_type)
1785 {
1786 struct l2cap_chan *c, *c1 = NULL;
1787
1788 read_lock(&chan_list_lock);
1789
1790 list_for_each_entry(c, &chan_list, global_l) {
1791 if (state && c->state != state)
1792 continue;
1793
1794 if (link_type == ACL_LINK && c->src_type != BDADDR_BREDR)
1795 continue;
1796
1797 if (link_type == LE_LINK && c->src_type == BDADDR_BREDR)
1798 continue;
1799
1800 if (c->psm == psm) {
1801 int src_match, dst_match;
1802 int src_any, dst_any;
1803
1804 /* Exact match. */
1805 src_match = !bacmp(&c->src, src);
1806 dst_match = !bacmp(&c->dst, dst);
1807 if (src_match && dst_match) {
1808 l2cap_chan_hold(c);
1809 read_unlock(&chan_list_lock);
1810 return c;
1811 }
1812
1813 /* Closest match */
1814 src_any = !bacmp(&c->src, BDADDR_ANY);
1815 dst_any = !bacmp(&c->dst, BDADDR_ANY);
1816 if ((src_match && dst_any) || (src_any && dst_match) ||
1817 (src_any && dst_any))
1818 c1 = c;
1819 }
1820 }
1821
1822 if (c1)
1823 l2cap_chan_hold(c1);
1824
1825 read_unlock(&chan_list_lock);
1826
1827 return c1;
1828 }
1829
1830 static void l2cap_monitor_timeout(struct work_struct *work)
1831 {
1832 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
1833 monitor_timer.work);
1834
1835 BT_DBG("chan %p", chan);
1836
1837 l2cap_chan_lock(chan);
1838
1839 if (!chan->conn) {
1840 l2cap_chan_unlock(chan);
1841 l2cap_chan_put(chan);
1842 return;
1843 }
1844
1845 l2cap_tx(chan, NULL, NULL, L2CAP_EV_MONITOR_TO);
1846
1847 l2cap_chan_unlock(chan);
1848 l2cap_chan_put(chan);
1849 }
1850
1851 static void l2cap_retrans_timeout(struct work_struct *work)
1852 {
1853 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
1854 retrans_timer.work);
1855
1856 BT_DBG("chan %p", chan);
1857
1858 l2cap_chan_lock(chan);
1859
1860 if (!chan->conn) {
1861 l2cap_chan_unlock(chan);
1862 l2cap_chan_put(chan);
1863 return;
1864 }
1865
1866 l2cap_tx(chan, NULL, NULL, L2CAP_EV_RETRANS_TO);
1867 l2cap_chan_unlock(chan);
1868 l2cap_chan_put(chan);
1869 }
1870
1871 static void l2cap_streaming_send(struct l2cap_chan *chan,
1872 struct sk_buff_head *skbs)
1873 {
1874 struct sk_buff *skb;
1875 struct l2cap_ctrl *control;
1876
1877 BT_DBG("chan %p, skbs %p", chan, skbs);
1878
1879 if (__chan_is_moving(chan))
1880 return;
1881
1882 skb_queue_splice_tail_init(skbs, &chan->tx_q);
1883
1884 while (!skb_queue_empty(&chan->tx_q)) {
1885
1886 skb = skb_dequeue(&chan->tx_q);
1887
1888 bt_cb(skb)->l2cap.retries = 1;
1889 control = &bt_cb(skb)->l2cap;
1890
1891 control->reqseq = 0;
1892 control->txseq = chan->next_tx_seq;
1893
1894 __pack_control(chan, control, skb);
1895
1896 if (chan->fcs == L2CAP_FCS_CRC16) {
1897 u16 fcs = crc16(0, (u8 *) skb->data, skb->len);
1898 put_unaligned_le16(fcs, skb_put(skb, L2CAP_FCS_SIZE));
1899 }
1900
1901 l2cap_do_send(chan, skb);
1902
1903 BT_DBG("Sent txseq %u", control->txseq);
1904
1905 chan->next_tx_seq = __next_seq(chan, chan->next_tx_seq);
1906 chan->frames_sent++;
1907 }
1908 }
1909
1910 static int l2cap_ertm_send(struct l2cap_chan *chan)
1911 {
1912 struct sk_buff *skb, *tx_skb;
1913 struct l2cap_ctrl *control;
1914 int sent = 0;
1915
1916 BT_DBG("chan %p", chan);
1917
1918 if (chan->state != BT_CONNECTED)
1919 return -ENOTCONN;
1920
1921 if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state))
1922 return 0;
1923
1924 if (__chan_is_moving(chan))
1925 return 0;
1926
1927 while (chan->tx_send_head &&
1928 chan->unacked_frames < chan->remote_tx_win &&
1929 chan->tx_state == L2CAP_TX_STATE_XMIT) {
1930
1931 skb = chan->tx_send_head;
1932
1933 bt_cb(skb)->l2cap.retries = 1;
1934 control = &bt_cb(skb)->l2cap;
1935
1936 if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state))
1937 control->final = 1;
1938
1939 control->reqseq = chan->buffer_seq;
1940 chan->last_acked_seq = chan->buffer_seq;
1941 control->txseq = chan->next_tx_seq;
1942
1943 __pack_control(chan, control, skb);
1944
1945 if (chan->fcs == L2CAP_FCS_CRC16) {
1946 u16 fcs = crc16(0, (u8 *) skb->data, skb->len);
1947 put_unaligned_le16(fcs, skb_put(skb, L2CAP_FCS_SIZE));
1948 }
1949
1950 /* Clone after data has been modified. Data is assumed to be
1951 read-only (for locking purposes) on cloned sk_buffs.
1952 */
1953 tx_skb = skb_clone(skb, GFP_KERNEL);
1954
1955 if (!tx_skb)
1956 break;
1957
1958 __set_retrans_timer(chan);
1959
1960 chan->next_tx_seq = __next_seq(chan, chan->next_tx_seq);
1961 chan->unacked_frames++;
1962 chan->frames_sent++;
1963 sent++;
1964
1965 if (skb_queue_is_last(&chan->tx_q, skb))
1966 chan->tx_send_head = NULL;
1967 else
1968 chan->tx_send_head = skb_queue_next(&chan->tx_q, skb);
1969
1970 l2cap_do_send(chan, tx_skb);
1971 BT_DBG("Sent txseq %u", control->txseq);
1972 }
1973
1974 BT_DBG("Sent %d, %u unacked, %u in ERTM queue", sent,
1975 chan->unacked_frames, skb_queue_len(&chan->tx_q));
1976
1977 return sent;
1978 }
1979
1980 static void l2cap_ertm_resend(struct l2cap_chan *chan)
1981 {
1982 struct l2cap_ctrl control;
1983 struct sk_buff *skb;
1984 struct sk_buff *tx_skb;
1985 u16 seq;
1986
1987 BT_DBG("chan %p", chan);
1988
1989 if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state))
1990 return;
1991
1992 if (__chan_is_moving(chan))
1993 return;
1994
1995 while (chan->retrans_list.head != L2CAP_SEQ_LIST_CLEAR) {
1996 seq = l2cap_seq_list_pop(&chan->retrans_list);
1997
1998 skb = l2cap_ertm_seq_in_queue(&chan->tx_q, seq);
1999 if (!skb) {
2000 BT_DBG("Error: Can't retransmit seq %d, frame missing",
2001 seq);
2002 continue;
2003 }
2004
2005 bt_cb(skb)->l2cap.retries++;
2006 control = bt_cb(skb)->l2cap;
2007
2008 if (chan->max_tx != 0 &&
2009 bt_cb(skb)->l2cap.retries > chan->max_tx) {
2010 BT_DBG("Retry limit exceeded (%d)", chan->max_tx);
2011 l2cap_send_disconn_req(chan, ECONNRESET);
2012 l2cap_seq_list_clear(&chan->retrans_list);
2013 break;
2014 }
2015
2016 control.reqseq = chan->buffer_seq;
2017 if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state))
2018 control.final = 1;
2019 else
2020 control.final = 0;
2021
2022 if (skb_cloned(skb)) {
2023 /* Cloned sk_buffs are read-only, so we need a
2024 * writeable copy
2025 */
2026 tx_skb = skb_copy(skb, GFP_KERNEL);
2027 } else {
2028 tx_skb = skb_clone(skb, GFP_KERNEL);
2029 }
2030
2031 if (!tx_skb) {
2032 l2cap_seq_list_clear(&chan->retrans_list);
2033 break;
2034 }
2035
2036 /* Update skb contents */
2037 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) {
2038 put_unaligned_le32(__pack_extended_control(&control),
2039 tx_skb->data + L2CAP_HDR_SIZE);
2040 } else {
2041 put_unaligned_le16(__pack_enhanced_control(&control),
2042 tx_skb->data + L2CAP_HDR_SIZE);
2043 }
2044
2045 /* Update FCS */
2046 if (chan->fcs == L2CAP_FCS_CRC16) {
2047 u16 fcs = crc16(0, (u8 *) tx_skb->data,
2048 tx_skb->len - L2CAP_FCS_SIZE);
2049 put_unaligned_le16(fcs, skb_tail_pointer(tx_skb) -
2050 L2CAP_FCS_SIZE);
2051 }
2052
2053 l2cap_do_send(chan, tx_skb);
2054
2055 BT_DBG("Resent txseq %d", control.txseq);
2056
2057 chan->last_acked_seq = chan->buffer_seq;
2058 }
2059 }
2060
2061 static void l2cap_retransmit(struct l2cap_chan *chan,
2062 struct l2cap_ctrl *control)
2063 {
2064 BT_DBG("chan %p, control %p", chan, control);
2065
2066 l2cap_seq_list_append(&chan->retrans_list, control->reqseq);
2067 l2cap_ertm_resend(chan);
2068 }
2069
2070 static void l2cap_retransmit_all(struct l2cap_chan *chan,
2071 struct l2cap_ctrl *control)
2072 {
2073 struct sk_buff *skb;
2074
2075 BT_DBG("chan %p, control %p", chan, control);
2076
2077 if (control->poll)
2078 set_bit(CONN_SEND_FBIT, &chan->conn_state);
2079
2080 l2cap_seq_list_clear(&chan->retrans_list);
2081
2082 if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state))
2083 return;
2084
2085 if (chan->unacked_frames) {
2086 skb_queue_walk(&chan->tx_q, skb) {
2087 if (bt_cb(skb)->l2cap.txseq == control->reqseq ||
2088 skb == chan->tx_send_head)
2089 break;
2090 }
2091
2092 skb_queue_walk_from(&chan->tx_q, skb) {
2093 if (skb == chan->tx_send_head)
2094 break;
2095
2096 l2cap_seq_list_append(&chan->retrans_list,
2097 bt_cb(skb)->l2cap.txseq);
2098 }
2099
2100 l2cap_ertm_resend(chan);
2101 }
2102 }
2103
2104 static void l2cap_send_ack(struct l2cap_chan *chan)
2105 {
2106 struct l2cap_ctrl control;
2107 u16 frames_to_ack = __seq_offset(chan, chan->buffer_seq,
2108 chan->last_acked_seq);
2109 int threshold;
2110
2111 BT_DBG("chan %p last_acked_seq %d buffer_seq %d",
2112 chan, chan->last_acked_seq, chan->buffer_seq);
2113
2114 memset(&control, 0, sizeof(control));
2115 control.sframe = 1;
2116
2117 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state) &&
2118 chan->rx_state == L2CAP_RX_STATE_RECV) {
2119 __clear_ack_timer(chan);
2120 control.super = L2CAP_SUPER_RNR;
2121 control.reqseq = chan->buffer_seq;
2122 l2cap_send_sframe(chan, &control);
2123 } else {
2124 if (!test_bit(CONN_REMOTE_BUSY, &chan->conn_state)) {
2125 l2cap_ertm_send(chan);
2126 /* If any i-frames were sent, they included an ack */
2127 if (chan->buffer_seq == chan->last_acked_seq)
2128 frames_to_ack = 0;
2129 }
2130
2131 /* Ack now if the window is 3/4ths full.
2132 * Calculate without mul or div
2133 */
2134 threshold = chan->ack_win;
2135 threshold += threshold << 1;
2136 threshold >>= 2;
2137
2138 BT_DBG("frames_to_ack %u, threshold %d", frames_to_ack,
2139 threshold);
2140
2141 if (frames_to_ack >= threshold) {
2142 __clear_ack_timer(chan);
2143 control.super = L2CAP_SUPER_RR;
2144 control.reqseq = chan->buffer_seq;
2145 l2cap_send_sframe(chan, &control);
2146 frames_to_ack = 0;
2147 }
2148
2149 if (frames_to_ack)
2150 __set_ack_timer(chan);
2151 }
2152 }
2153
2154 static inline int l2cap_skbuff_fromiovec(struct l2cap_chan *chan,
2155 struct msghdr *msg, int len,
2156 int count, struct sk_buff *skb)
2157 {
2158 struct l2cap_conn *conn = chan->conn;
2159 struct sk_buff **frag;
2160 int sent = 0;
2161
2162 if (!copy_from_iter_full(skb_put(skb, count), count, &msg->msg_iter))
2163 return -EFAULT;
2164
2165 sent += count;
2166 len -= count;
2167
2168 /* Continuation fragments (no L2CAP header) */
2169 frag = &skb_shinfo(skb)->frag_list;
2170 while (len) {
2171 struct sk_buff *tmp;
2172
2173 count = min_t(unsigned int, conn->mtu, len);
2174
2175 tmp = chan->ops->alloc_skb(chan, 0, count,
2176 msg->msg_flags & MSG_DONTWAIT);
2177 if (IS_ERR(tmp))
2178 return PTR_ERR(tmp);
2179
2180 *frag = tmp;
2181
2182 if (!copy_from_iter_full(skb_put(*frag, count), count,
2183 &msg->msg_iter))
2184 return -EFAULT;
2185
2186 sent += count;
2187 len -= count;
2188
2189 skb->len += (*frag)->len;
2190 skb->data_len += (*frag)->len;
2191
2192 frag = &(*frag)->next;
2193 }
2194
2195 return sent;
2196 }
2197
2198 static struct sk_buff *l2cap_create_connless_pdu(struct l2cap_chan *chan,
2199 struct msghdr *msg, size_t len)
2200 {
2201 struct l2cap_conn *conn = chan->conn;
2202 struct sk_buff *skb;
2203 int err, count, hlen = L2CAP_HDR_SIZE + L2CAP_PSMLEN_SIZE;
2204 struct l2cap_hdr *lh;
2205
2206 BT_DBG("chan %p psm 0x%2.2x len %zu", chan,
2207 __le16_to_cpu(chan->psm), len);
2208
2209 count = min_t(unsigned int, (conn->mtu - hlen), len);
2210
2211 skb = chan->ops->alloc_skb(chan, hlen, count,
2212 msg->msg_flags & MSG_DONTWAIT);
2213 if (IS_ERR(skb))
2214 return skb;
2215
2216 /* Create L2CAP header */
2217 lh = skb_put(skb, L2CAP_HDR_SIZE);
2218 lh->cid = cpu_to_le16(chan->dcid);
2219 lh->len = cpu_to_le16(len + L2CAP_PSMLEN_SIZE);
2220 put_unaligned(chan->psm, (__le16 *) skb_put(skb, L2CAP_PSMLEN_SIZE));
2221
2222 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2223 if (unlikely(err < 0)) {
2224 kfree_skb(skb);
2225 return ERR_PTR(err);
2226 }
2227 return skb;
2228 }
2229
2230 static struct sk_buff *l2cap_create_basic_pdu(struct l2cap_chan *chan,
2231 struct msghdr *msg, size_t len)
2232 {
2233 struct l2cap_conn *conn = chan->conn;
2234 struct sk_buff *skb;
2235 int err, count;
2236 struct l2cap_hdr *lh;
2237
2238 BT_DBG("chan %p len %zu", chan, len);
2239
2240 count = min_t(unsigned int, (conn->mtu - L2CAP_HDR_SIZE), len);
2241
2242 skb = chan->ops->alloc_skb(chan, L2CAP_HDR_SIZE, count,
2243 msg->msg_flags & MSG_DONTWAIT);
2244 if (IS_ERR(skb))
2245 return skb;
2246
2247 /* Create L2CAP header */
2248 lh = skb_put(skb, L2CAP_HDR_SIZE);
2249 lh->cid = cpu_to_le16(chan->dcid);
2250 lh->len = cpu_to_le16(len);
2251
2252 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2253 if (unlikely(err < 0)) {
2254 kfree_skb(skb);
2255 return ERR_PTR(err);
2256 }
2257 return skb;
2258 }
2259
2260 static struct sk_buff *l2cap_create_iframe_pdu(struct l2cap_chan *chan,
2261 struct msghdr *msg, size_t len,
2262 u16 sdulen)
2263 {
2264 struct l2cap_conn *conn = chan->conn;
2265 struct sk_buff *skb;
2266 int err, count, hlen;
2267 struct l2cap_hdr *lh;
2268
2269 BT_DBG("chan %p len %zu", chan, len);
2270
2271 if (!conn)
2272 return ERR_PTR(-ENOTCONN);
2273
2274 hlen = __ertm_hdr_size(chan);
2275
2276 if (sdulen)
2277 hlen += L2CAP_SDULEN_SIZE;
2278
2279 if (chan->fcs == L2CAP_FCS_CRC16)
2280 hlen += L2CAP_FCS_SIZE;
2281
2282 count = min_t(unsigned int, (conn->mtu - hlen), len);
2283
2284 skb = chan->ops->alloc_skb(chan, hlen, count,
2285 msg->msg_flags & MSG_DONTWAIT);
2286 if (IS_ERR(skb))
2287 return skb;
2288
2289 /* Create L2CAP header */
2290 lh = skb_put(skb, L2CAP_HDR_SIZE);
2291 lh->cid = cpu_to_le16(chan->dcid);
2292 lh->len = cpu_to_le16(len + (hlen - L2CAP_HDR_SIZE));
2293
2294 /* Control header is populated later */
2295 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
2296 put_unaligned_le32(0, skb_put(skb, L2CAP_EXT_CTRL_SIZE));
2297 else
2298 put_unaligned_le16(0, skb_put(skb, L2CAP_ENH_CTRL_SIZE));
2299
2300 if (sdulen)
2301 put_unaligned_le16(sdulen, skb_put(skb, L2CAP_SDULEN_SIZE));
2302
2303 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2304 if (unlikely(err < 0)) {
2305 kfree_skb(skb);
2306 return ERR_PTR(err);
2307 }
2308
2309 bt_cb(skb)->l2cap.fcs = chan->fcs;
2310 bt_cb(skb)->l2cap.retries = 0;
2311 return skb;
2312 }
2313
2314 static int l2cap_segment_sdu(struct l2cap_chan *chan,
2315 struct sk_buff_head *seg_queue,
2316 struct msghdr *msg, size_t len)
2317 {
2318 struct sk_buff *skb;
2319 u16 sdu_len;
2320 size_t pdu_len;
2321 u8 sar;
2322
2323 BT_DBG("chan %p, msg %p, len %zu", chan, msg, len);
2324
2325 /* It is critical that ERTM PDUs fit in a single HCI fragment,
2326 * so fragmented skbs are not used. The HCI layer's handling
2327 * of fragmented skbs is not compatible with ERTM's queueing.
2328 */
2329
2330 /* PDU size is derived from the HCI MTU */
2331 pdu_len = chan->conn->mtu;
2332
2333 /* Constrain PDU size for BR/EDR connections */
2334 if (!chan->hs_hcon)
2335 pdu_len = min_t(size_t, pdu_len, L2CAP_BREDR_MAX_PAYLOAD);
2336
2337 /* Adjust for largest possible L2CAP overhead. */
2338 if (chan->fcs)
2339 pdu_len -= L2CAP_FCS_SIZE;
2340
2341 pdu_len -= __ertm_hdr_size(chan);
2342
2343 /* Remote device may have requested smaller PDUs */
2344 pdu_len = min_t(size_t, pdu_len, chan->remote_mps);
2345
2346 if (len <= pdu_len) {
2347 sar = L2CAP_SAR_UNSEGMENTED;
2348 sdu_len = 0;
2349 pdu_len = len;
2350 } else {
2351 sar = L2CAP_SAR_START;
2352 sdu_len = len;
2353 }
2354
2355 while (len > 0) {
2356 skb = l2cap_create_iframe_pdu(chan, msg, pdu_len, sdu_len);
2357
2358 if (IS_ERR(skb)) {
2359 __skb_queue_purge(seg_queue);
2360 return PTR_ERR(skb);
2361 }
2362
2363 bt_cb(skb)->l2cap.sar = sar;
2364 __skb_queue_tail(seg_queue, skb);
2365
2366 len -= pdu_len;
2367 if (sdu_len)
2368 sdu_len = 0;
2369
2370 if (len <= pdu_len) {
2371 sar = L2CAP_SAR_END;
2372 pdu_len = len;
2373 } else {
2374 sar = L2CAP_SAR_CONTINUE;
2375 }
2376 }
2377
2378 return 0;
2379 }
2380
2381 static struct sk_buff *l2cap_create_le_flowctl_pdu(struct l2cap_chan *chan,
2382 struct msghdr *msg,
2383 size_t len, u16 sdulen)
2384 {
2385 struct l2cap_conn *conn = chan->conn;
2386 struct sk_buff *skb;
2387 int err, count, hlen;
2388 struct l2cap_hdr *lh;
2389
2390 BT_DBG("chan %p len %zu", chan, len);
2391
2392 if (!conn)
2393 return ERR_PTR(-ENOTCONN);
2394
2395 hlen = L2CAP_HDR_SIZE;
2396
2397 if (sdulen)
2398 hlen += L2CAP_SDULEN_SIZE;
2399
2400 count = min_t(unsigned int, (conn->mtu - hlen), len);
2401
2402 skb = chan->ops->alloc_skb(chan, hlen, count,
2403 msg->msg_flags & MSG_DONTWAIT);
2404 if (IS_ERR(skb))
2405 return skb;
2406
2407 /* Create L2CAP header */
2408 lh = skb_put(skb, L2CAP_HDR_SIZE);
2409 lh->cid = cpu_to_le16(chan->dcid);
2410 lh->len = cpu_to_le16(len + (hlen - L2CAP_HDR_SIZE));
2411
2412 if (sdulen)
2413 put_unaligned_le16(sdulen, skb_put(skb, L2CAP_SDULEN_SIZE));
2414
2415 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2416 if (unlikely(err < 0)) {
2417 kfree_skb(skb);
2418 return ERR_PTR(err);
2419 }
2420
2421 return skb;
2422 }
2423
2424 static int l2cap_segment_le_sdu(struct l2cap_chan *chan,
2425 struct sk_buff_head *seg_queue,
2426 struct msghdr *msg, size_t len)
2427 {
2428 struct sk_buff *skb;
2429 size_t pdu_len;
2430 u16 sdu_len;
2431
2432 BT_DBG("chan %p, msg %p, len %zu", chan, msg, len);
2433
2434 sdu_len = len;
2435 pdu_len = chan->remote_mps - L2CAP_SDULEN_SIZE;
2436
2437 while (len > 0) {
2438 if (len <= pdu_len)
2439 pdu_len = len;
2440
2441 skb = l2cap_create_le_flowctl_pdu(chan, msg, pdu_len, sdu_len);
2442 if (IS_ERR(skb)) {
2443 __skb_queue_purge(seg_queue);
2444 return PTR_ERR(skb);
2445 }
2446
2447 __skb_queue_tail(seg_queue, skb);
2448
2449 len -= pdu_len;
2450
2451 if (sdu_len) {
2452 sdu_len = 0;
2453 pdu_len += L2CAP_SDULEN_SIZE;
2454 }
2455 }
2456
2457 return 0;
2458 }
2459
2460 static void l2cap_le_flowctl_send(struct l2cap_chan *chan)
2461 {
2462 int sent = 0;
2463
2464 BT_DBG("chan %p", chan);
2465
2466 while (chan->tx_credits && !skb_queue_empty(&chan->tx_q)) {
2467 l2cap_do_send(chan, skb_dequeue(&chan->tx_q));
2468 chan->tx_credits--;
2469 sent++;
2470 }
2471
2472 BT_DBG("Sent %d credits %u queued %u", sent, chan->tx_credits,
2473 skb_queue_len(&chan->tx_q));
2474 }
2475
2476 int l2cap_chan_send(struct l2cap_chan *chan, struct msghdr *msg, size_t len)
2477 {
2478 struct sk_buff *skb;
2479 int err;
2480 struct sk_buff_head seg_queue;
2481
2482 if (!chan->conn)
2483 return -ENOTCONN;
2484
2485 /* Connectionless channel */
2486 if (chan->chan_type == L2CAP_CHAN_CONN_LESS) {
2487 skb = l2cap_create_connless_pdu(chan, msg, len);
2488 if (IS_ERR(skb))
2489 return PTR_ERR(skb);
2490
2491 /* Channel lock is released before requesting new skb and then
2492 * reacquired thus we need to recheck channel state.
2493 */
2494 if (chan->state != BT_CONNECTED) {
2495 kfree_skb(skb);
2496 return -ENOTCONN;
2497 }
2498
2499 l2cap_do_send(chan, skb);
2500 return len;
2501 }
2502
2503 switch (chan->mode) {
2504 case L2CAP_MODE_LE_FLOWCTL:
2505 /* Check outgoing MTU */
2506 if (len > chan->omtu)
2507 return -EMSGSIZE;
2508
2509 __skb_queue_head_init(&seg_queue);
2510
2511 err = l2cap_segment_le_sdu(chan, &seg_queue, msg, len);
2512
2513 if (chan->state != BT_CONNECTED) {
2514 __skb_queue_purge(&seg_queue);
2515 err = -ENOTCONN;
2516 }
2517
2518 if (err)
2519 return err;
2520
2521 skb_queue_splice_tail_init(&seg_queue, &chan->tx_q);
2522
2523 l2cap_le_flowctl_send(chan);
2524
2525 if (!chan->tx_credits)
2526 chan->ops->suspend(chan);
2527
2528 err = len;
2529
2530 break;
2531
2532 case L2CAP_MODE_BASIC:
2533 /* Check outgoing MTU */
2534 if (len > chan->omtu)
2535 return -EMSGSIZE;
2536
2537 /* Create a basic PDU */
2538 skb = l2cap_create_basic_pdu(chan, msg, len);
2539 if (IS_ERR(skb))
2540 return PTR_ERR(skb);
2541
2542 /* Channel lock is released before requesting new skb and then
2543 * reacquired thus we need to recheck channel state.
2544 */
2545 if (chan->state != BT_CONNECTED) {
2546 kfree_skb(skb);
2547 return -ENOTCONN;
2548 }
2549
2550 l2cap_do_send(chan, skb);
2551 err = len;
2552 break;
2553
2554 case L2CAP_MODE_ERTM:
2555 case L2CAP_MODE_STREAMING:
2556 /* Check outgoing MTU */
2557 if (len > chan->omtu) {
2558 err = -EMSGSIZE;
2559 break;
2560 }
2561
2562 __skb_queue_head_init(&seg_queue);
2563
2564 /* Do segmentation before calling in to the state machine,
2565 * since it's possible to block while waiting for memory
2566 * allocation.
2567 */
2568 err = l2cap_segment_sdu(chan, &seg_queue, msg, len);
2569
2570 /* The channel could have been closed while segmenting,
2571 * check that it is still connected.
2572 */
2573 if (chan->state != BT_CONNECTED) {
2574 __skb_queue_purge(&seg_queue);
2575 err = -ENOTCONN;
2576 }
2577
2578 if (err)
2579 break;
2580
2581 if (chan->mode == L2CAP_MODE_ERTM)
2582 l2cap_tx(chan, NULL, &seg_queue, L2CAP_EV_DATA_REQUEST);
2583 else
2584 l2cap_streaming_send(chan, &seg_queue);
2585
2586 err = len;
2587
2588 /* If the skbs were not queued for sending, they'll still be in
2589 * seg_queue and need to be purged.
2590 */
2591 __skb_queue_purge(&seg_queue);
2592 break;
2593
2594 default:
2595 BT_DBG("bad state %1.1x", chan->mode);
2596 err = -EBADFD;
2597 }
2598
2599 return err;
2600 }
2601 EXPORT_SYMBOL_GPL(l2cap_chan_send);
2602
2603 static void l2cap_send_srej(struct l2cap_chan *chan, u16 txseq)
2604 {
2605 struct l2cap_ctrl control;
2606 u16 seq;
2607
2608 BT_DBG("chan %p, txseq %u", chan, txseq);
2609
2610 memset(&control, 0, sizeof(control));
2611 control.sframe = 1;
2612 control.super = L2CAP_SUPER_SREJ;
2613
2614 for (seq = chan->expected_tx_seq; seq != txseq;
2615 seq = __next_seq(chan, seq)) {
2616 if (!l2cap_ertm_seq_in_queue(&chan->srej_q, seq)) {
2617 control.reqseq = seq;
2618 l2cap_send_sframe(chan, &control);
2619 l2cap_seq_list_append(&chan->srej_list, seq);
2620 }
2621 }
2622
2623 chan->expected_tx_seq = __next_seq(chan, txseq);
2624 }
2625
2626 static void l2cap_send_srej_tail(struct l2cap_chan *chan)
2627 {
2628 struct l2cap_ctrl control;
2629
2630 BT_DBG("chan %p", chan);
2631
2632 if (chan->srej_list.tail == L2CAP_SEQ_LIST_CLEAR)
2633 return;
2634
2635 memset(&control, 0, sizeof(control));
2636 control.sframe = 1;
2637 control.super = L2CAP_SUPER_SREJ;
2638 control.reqseq = chan->srej_list.tail;
2639 l2cap_send_sframe(chan, &control);
2640 }
2641
2642 static void l2cap_send_srej_list(struct l2cap_chan *chan, u16 txseq)
2643 {
2644 struct l2cap_ctrl control;
2645 u16 initial_head;
2646 u16 seq;
2647
2648 BT_DBG("chan %p, txseq %u", chan, txseq);
2649
2650 memset(&control, 0, sizeof(control));
2651 control.sframe = 1;
2652 control.super = L2CAP_SUPER_SREJ;
2653
2654 /* Capture initial list head to allow only one pass through the list. */
2655 initial_head = chan->srej_list.head;
2656
2657 do {
2658 seq = l2cap_seq_list_pop(&chan->srej_list);
2659 if (seq == txseq || seq == L2CAP_SEQ_LIST_CLEAR)
2660 break;
2661
2662 control.reqseq = seq;
2663 l2cap_send_sframe(chan, &control);
2664 l2cap_seq_list_append(&chan->srej_list, seq);
2665 } while (chan->srej_list.head != initial_head);
2666 }
2667
2668 static void l2cap_process_reqseq(struct l2cap_chan *chan, u16 reqseq)
2669 {
2670 struct sk_buff *acked_skb;
2671 u16 ackseq;
2672
2673 BT_DBG("chan %p, reqseq %u", chan, reqseq);
2674
2675 if (chan->unacked_frames == 0 || reqseq == chan->expected_ack_seq)
2676 return;
2677
2678 BT_DBG("expected_ack_seq %u, unacked_frames %u",
2679 chan->expected_ack_seq, chan->unacked_frames);
2680
2681 for (ackseq = chan->expected_ack_seq; ackseq != reqseq;
2682 ackseq = __next_seq(chan, ackseq)) {
2683
2684 acked_skb = l2cap_ertm_seq_in_queue(&chan->tx_q, ackseq);
2685 if (acked_skb) {
2686 skb_unlink(acked_skb, &chan->tx_q);
2687 kfree_skb(acked_skb);
2688 chan->unacked_frames--;
2689 }
2690 }
2691
2692 chan->expected_ack_seq = reqseq;
2693
2694 if (chan->unacked_frames == 0)
2695 __clear_retrans_timer(chan);
2696
2697 BT_DBG("unacked_frames %u", chan->unacked_frames);
2698 }
2699
2700 static void l2cap_abort_rx_srej_sent(struct l2cap_chan *chan)
2701 {
2702 BT_DBG("chan %p", chan);
2703
2704 chan->expected_tx_seq = chan->buffer_seq;
2705 l2cap_seq_list_clear(&chan->srej_list);
2706 skb_queue_purge(&chan->srej_q);
2707 chan->rx_state = L2CAP_RX_STATE_RECV;
2708 }
2709
2710 static void l2cap_tx_state_xmit(struct l2cap_chan *chan,
2711 struct l2cap_ctrl *control,
2712 struct sk_buff_head *skbs, u8 event)
2713 {
2714 BT_DBG("chan %p, control %p, skbs %p, event %d", chan, control, skbs,
2715 event);
2716
2717 switch (event) {
2718 case L2CAP_EV_DATA_REQUEST:
2719 if (chan->tx_send_head == NULL)
2720 chan->tx_send_head = skb_peek(skbs);
2721
2722 skb_queue_splice_tail_init(skbs, &chan->tx_q);
2723 l2cap_ertm_send(chan);
2724 break;
2725 case L2CAP_EV_LOCAL_BUSY_DETECTED:
2726 BT_DBG("Enter LOCAL_BUSY");
2727 set_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2728
2729 if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) {
2730 /* The SREJ_SENT state must be aborted if we are to
2731 * enter the LOCAL_BUSY state.
2732 */
2733 l2cap_abort_rx_srej_sent(chan);
2734 }
2735
2736 l2cap_send_ack(chan);
2737
2738 break;
2739 case L2CAP_EV_LOCAL_BUSY_CLEAR:
2740 BT_DBG("Exit LOCAL_BUSY");
2741 clear_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2742
2743 if (test_bit(CONN_RNR_SENT, &chan->conn_state)) {
2744 struct l2cap_ctrl local_control;
2745
2746 memset(&local_control, 0, sizeof(local_control));
2747 local_control.sframe = 1;
2748 local_control.super = L2CAP_SUPER_RR;
2749 local_control.poll = 1;
2750 local_control.reqseq = chan->buffer_seq;
2751 l2cap_send_sframe(chan, &local_control);
2752
2753 chan->retry_count = 1;
2754 __set_monitor_timer(chan);
2755 chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2756 }
2757 break;
2758 case L2CAP_EV_RECV_REQSEQ_AND_FBIT:
2759 l2cap_process_reqseq(chan, control->reqseq);
2760 break;
2761 case L2CAP_EV_EXPLICIT_POLL:
2762 l2cap_send_rr_or_rnr(chan, 1);
2763 chan->retry_count = 1;
2764 __set_monitor_timer(chan);
2765 __clear_ack_timer(chan);
2766 chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2767 break;
2768 case L2CAP_EV_RETRANS_TO:
2769 l2cap_send_rr_or_rnr(chan, 1);
2770 chan->retry_count = 1;
2771 __set_monitor_timer(chan);
2772 chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2773 break;
2774 case L2CAP_EV_RECV_FBIT:
2775 /* Nothing to process */
2776 break;
2777 default:
2778 break;
2779 }
2780 }
2781
2782 static void l2cap_tx_state_wait_f(struct l2cap_chan *chan,
2783 struct l2cap_ctrl *control,
2784 struct sk_buff_head *skbs, u8 event)
2785 {
2786 BT_DBG("chan %p, control %p, skbs %p, event %d", chan, control, skbs,
2787 event);
2788
2789 switch (event) {
2790 case L2CAP_EV_DATA_REQUEST:
2791 if (chan->tx_send_head == NULL)
2792 chan->tx_send_head = skb_peek(skbs);
2793 /* Queue data, but don't send. */
2794 skb_queue_splice_tail_init(skbs, &chan->tx_q);
2795 break;
2796 case L2CAP_EV_LOCAL_BUSY_DETECTED:
2797 BT_DBG("Enter LOCAL_BUSY");
2798 set_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2799
2800 if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) {
2801 /* The SREJ_SENT state must be aborted if we are to
2802 * enter the LOCAL_BUSY state.
2803 */
2804 l2cap_abort_rx_srej_sent(chan);
2805 }
2806
2807 l2cap_send_ack(chan);
2808
2809 break;
2810 case L2CAP_EV_LOCAL_BUSY_CLEAR:
2811 BT_DBG("Exit LOCAL_BUSY");
2812 clear_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2813
2814 if (test_bit(CONN_RNR_SENT, &chan->conn_state)) {
2815 struct l2cap_ctrl local_control;
2816 memset(&local_control, 0, sizeof(local_control));
2817 local_control.sframe = 1;
2818 local_control.super = L2CAP_SUPER_RR;
2819 local_control.poll = 1;
2820 local_control.reqseq = chan->buffer_seq;
2821 l2cap_send_sframe(chan, &local_control);
2822
2823 chan->retry_count = 1;
2824 __set_monitor_timer(chan);
2825 chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2826 }
2827 break;
2828 case L2CAP_EV_RECV_REQSEQ_AND_FBIT:
2829 l2cap_process_reqseq(chan, control->reqseq);
2830
2831 /* Fall through */
2832
2833 case L2CAP_EV_RECV_FBIT:
2834 if (control && control->final) {
2835 __clear_monitor_timer(chan);
2836 if (chan->unacked_frames > 0)
2837 __set_retrans_timer(chan);
2838 chan->retry_count = 0;
2839 chan->tx_state = L2CAP_TX_STATE_XMIT;
2840 BT_DBG("recv fbit tx_state 0x2.2%x", chan->tx_state);
2841 }
2842 break;
2843 case L2CAP_EV_EXPLICIT_POLL:
2844 /* Ignore */
2845 break;
2846 case L2CAP_EV_MONITOR_TO:
2847 if (chan->max_tx == 0 || chan->retry_count < chan->max_tx) {
2848 l2cap_send_rr_or_rnr(chan, 1);
2849 __set_monitor_timer(chan);
2850 chan->retry_count++;
2851 } else {
2852 l2cap_send_disconn_req(chan, ECONNABORTED);
2853 }
2854 break;
2855 default:
2856 break;
2857 }
2858 }
2859
2860 static void l2cap_tx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
2861 struct sk_buff_head *skbs, u8 event)
2862 {
2863 BT_DBG("chan %p, control %p, skbs %p, event %d, state %d",
2864 chan, control, skbs, event, chan->tx_state);
2865
2866 switch (chan->tx_state) {
2867 case L2CAP_TX_STATE_XMIT:
2868 l2cap_tx_state_xmit(chan, control, skbs, event);
2869 break;
2870 case L2CAP_TX_STATE_WAIT_F:
2871 l2cap_tx_state_wait_f(chan, control, skbs, event);
2872 break;
2873 default:
2874 /* Ignore event */
2875 break;
2876 }
2877 }
2878
2879 static void l2cap_pass_to_tx(struct l2cap_chan *chan,
2880 struct l2cap_ctrl *control)
2881 {
2882 BT_DBG("chan %p, control %p", chan, control);
2883 l2cap_tx(chan, control, NULL, L2CAP_EV_RECV_REQSEQ_AND_FBIT);
2884 }
2885
2886 static void l2cap_pass_to_tx_fbit(struct l2cap_chan *chan,
2887 struct l2cap_ctrl *control)
2888 {
2889 BT_DBG("chan %p, control %p", chan, control);
2890 l2cap_tx(chan, control, NULL, L2CAP_EV_RECV_FBIT);
2891 }
2892
2893 /* Copy frame to all raw sockets on that connection */
2894 static void l2cap_raw_recv(struct l2cap_conn *conn, struct sk_buff *skb)
2895 {
2896 struct sk_buff *nskb;
2897 struct l2cap_chan *chan;
2898
2899 BT_DBG("conn %p", conn);
2900
2901 mutex_lock(&conn->chan_lock);
2902
2903 list_for_each_entry(chan, &conn->chan_l, list) {
2904 if (chan->chan_type != L2CAP_CHAN_RAW)
2905 continue;
2906
2907 /* Don't send frame to the channel it came from */
2908 if (bt_cb(skb)->l2cap.chan == chan)
2909 continue;
2910
2911 nskb = skb_clone(skb, GFP_KERNEL);
2912 if (!nskb)
2913 continue;
2914 if (chan->ops->recv(chan, nskb))
2915 kfree_skb(nskb);
2916 }
2917
2918 mutex_unlock(&conn->chan_lock);
2919 }
2920
2921 /* ---- L2CAP signalling commands ---- */
2922 static struct sk_buff *l2cap_build_cmd(struct l2cap_conn *conn, u8 code,
2923 u8 ident, u16 dlen, void *data)
2924 {
2925 struct sk_buff *skb, **frag;
2926 struct l2cap_cmd_hdr *cmd;
2927 struct l2cap_hdr *lh;
2928 int len, count;
2929
2930 BT_DBG("conn %p, code 0x%2.2x, ident 0x%2.2x, len %u",
2931 conn, code, ident, dlen);
2932
2933 if (conn->mtu < L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE)
2934 return NULL;
2935
2936 len = L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE + dlen;
2937 count = min_t(unsigned int, conn->mtu, len);
2938
2939 skb = bt_skb_alloc(count, GFP_KERNEL);
2940 if (!skb)
2941 return NULL;
2942
2943 lh = skb_put(skb, L2CAP_HDR_SIZE);
2944 lh->len = cpu_to_le16(L2CAP_CMD_HDR_SIZE + dlen);
2945
2946 if (conn->hcon->type == LE_LINK)
2947 lh->cid = cpu_to_le16(L2CAP_CID_LE_SIGNALING);
2948 else
2949 lh->cid = cpu_to_le16(L2CAP_CID_SIGNALING);
2950
2951 cmd = skb_put(skb, L2CAP_CMD_HDR_SIZE);
2952 cmd->code = code;
2953 cmd->ident = ident;
2954 cmd->len = cpu_to_le16(dlen);
2955
2956 if (dlen) {
2957 count -= L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE;
2958 skb_put_data(skb, data, count);
2959 data += count;
2960 }
2961
2962 len -= skb->len;
2963
2964 /* Continuation fragments (no L2CAP header) */
2965 frag = &skb_shinfo(skb)->frag_list;
2966 while (len) {
2967 count = min_t(unsigned int, conn->mtu, len);
2968
2969 *frag = bt_skb_alloc(count, GFP_KERNEL);
2970 if (!*frag)
2971 goto fail;
2972
2973 skb_put_data(*frag, data, count);
2974
2975 len -= count;
2976 data += count;
2977
2978 frag = &(*frag)->next;
2979 }
2980
2981 return skb;
2982
2983 fail:
2984 kfree_skb(skb);
2985 return NULL;
2986 }
2987
2988 static inline int l2cap_get_conf_opt(void **ptr, int *type, int *olen,
2989 unsigned long *val)
2990 {
2991 struct l2cap_conf_opt *opt = *ptr;
2992 int len;
2993
2994 len = L2CAP_CONF_OPT_SIZE + opt->len;
2995 *ptr += len;
2996
2997 *type = opt->type;
2998 *olen = opt->len;
2999
3000 switch (opt->len) {
3001 case 1:
3002 *val = *((u8 *) opt->val);
3003 break;
3004
3005 case 2:
3006 *val = get_unaligned_le16(opt->val);
3007 break;
3008
3009 case 4:
3010 *val = get_unaligned_le32(opt->val);
3011 break;
3012
3013 default:
3014 *val = (unsigned long) opt->val;
3015 break;
3016 }
3017
3018 BT_DBG("type 0x%2.2x len %u val 0x%lx", *type, opt->len, *val);
3019 return len;
3020 }
3021
3022 static void l2cap_add_conf_opt(void **ptr, u8 type, u8 len, unsigned long val, size_t size)
3023 {
3024 struct l2cap_conf_opt *opt = *ptr;
3025
3026 BT_DBG("type 0x%2.2x len %u val 0x%lx", type, len, val);
3027
3028 if (size < L2CAP_CONF_OPT_SIZE + len)
3029 return;
3030
3031 opt->type = type;
3032 opt->len = len;
3033
3034 switch (len) {
3035 case 1:
3036 *((u8 *) opt->val) = val;
3037 break;
3038
3039 case 2:
3040 put_unaligned_le16(val, opt->val);
3041 break;
3042
3043 case 4:
3044 put_unaligned_le32(val, opt->val);
3045 break;
3046
3047 default:
3048 memcpy(opt->val, (void *) val, len);
3049 break;
3050 }
3051
3052 *ptr += L2CAP_CONF_OPT_SIZE + len;
3053 }
3054
3055 static void l2cap_add_opt_efs(void **ptr, struct l2cap_chan *chan, size_t size)
3056 {
3057 struct l2cap_conf_efs efs;
3058
3059 switch (chan->mode) {
3060 case L2CAP_MODE_ERTM:
3061 efs.id = chan->local_id;
3062 efs.stype = chan->local_stype;
3063 efs.msdu = cpu_to_le16(chan->local_msdu);
3064 efs.sdu_itime = cpu_to_le32(chan->local_sdu_itime);
3065 efs.acc_lat = cpu_to_le32(L2CAP_DEFAULT_ACC_LAT);
3066 efs.flush_to = cpu_to_le32(L2CAP_EFS_DEFAULT_FLUSH_TO);
3067 break;
3068
3069 case L2CAP_MODE_STREAMING:
3070 efs.id = 1;
3071 efs.stype = L2CAP_SERV_BESTEFFORT;
3072 efs.msdu = cpu_to_le16(chan->local_msdu);
3073 efs.sdu_itime = cpu_to_le32(chan->local_sdu_itime);
3074 efs.acc_lat = 0;
3075 efs.flush_to = 0;
3076 break;
3077
3078 default:
3079 return;
3080 }
3081
3082 l2cap_add_conf_opt(ptr, L2CAP_CONF_EFS, sizeof(efs),
3083 (unsigned long) &efs, size);
3084 }
3085
3086 static void l2cap_ack_timeout(struct work_struct *work)
3087 {
3088 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
3089 ack_timer.work);
3090 u16 frames_to_ack;
3091
3092 BT_DBG("chan %p", chan);
3093
3094 l2cap_chan_lock(chan);
3095
3096 frames_to_ack = __seq_offset(chan, chan->buffer_seq,
3097 chan->last_acked_seq);
3098
3099 if (frames_to_ack)
3100 l2cap_send_rr_or_rnr(chan, 0);
3101
3102 l2cap_chan_unlock(chan);
3103 l2cap_chan_put(chan);
3104 }
3105
3106 int l2cap_ertm_init(struct l2cap_chan *chan)
3107 {
3108 int err;
3109
3110 chan->next_tx_seq = 0;
3111 chan->expected_tx_seq = 0;
3112 chan->expected_ack_seq = 0;
3113 chan->unacked_frames = 0;
3114 chan->buffer_seq = 0;
3115 chan->frames_sent = 0;
3116 chan->last_acked_seq = 0;
3117 chan->sdu = NULL;
3118 chan->sdu_last_frag = NULL;
3119 chan->sdu_len = 0;
3120
3121 skb_queue_head_init(&chan->tx_q);
3122
3123 chan->local_amp_id = AMP_ID_BREDR;
3124 chan->move_id = AMP_ID_BREDR;
3125 chan->move_state = L2CAP_MOVE_STABLE;
3126 chan->move_role = L2CAP_MOVE_ROLE_NONE;
3127
3128 if (chan->mode != L2CAP_MODE_ERTM)
3129 return 0;
3130
3131 chan->rx_state = L2CAP_RX_STATE_RECV;
3132 chan->tx_state = L2CAP_TX_STATE_XMIT;
3133
3134 INIT_DELAYED_WORK(&chan->retrans_timer, l2cap_retrans_timeout);
3135 INIT_DELAYED_WORK(&chan->monitor_timer, l2cap_monitor_timeout);
3136 INIT_DELAYED_WORK(&chan->ack_timer, l2cap_ack_timeout);
3137
3138 skb_queue_head_init(&chan->srej_q);
3139
3140 err = l2cap_seq_list_init(&chan->srej_list, chan->tx_win);
3141 if (err < 0)
3142 return err;
3143
3144 err = l2cap_seq_list_init(&chan->retrans_list, chan->remote_tx_win);
3145 if (err < 0)
3146 l2cap_seq_list_free(&chan->srej_list);
3147
3148 return err;
3149 }
3150
3151 static inline __u8 l2cap_select_mode(__u8 mode, __u16 remote_feat_mask)
3152 {
3153 switch (mode) {
3154 case L2CAP_MODE_STREAMING:
3155 case L2CAP_MODE_ERTM:
3156 if (l2cap_mode_supported(mode, remote_feat_mask))
3157 return mode;
3158 /* fall through */
3159 default:
3160 return L2CAP_MODE_BASIC;
3161 }
3162 }
3163
3164 static inline bool __l2cap_ews_supported(struct l2cap_conn *conn)
3165 {
3166 return ((conn->local_fixed_chan & L2CAP_FC_A2MP) &&
3167 (conn->feat_mask & L2CAP_FEAT_EXT_WINDOW));
3168 }
3169
3170 static inline bool __l2cap_efs_supported(struct l2cap_conn *conn)
3171 {
3172 return ((conn->local_fixed_chan & L2CAP_FC_A2MP) &&
3173 (conn->feat_mask & L2CAP_FEAT_EXT_FLOW));
3174 }
3175
3176 static void __l2cap_set_ertm_timeouts(struct l2cap_chan *chan,
3177 struct l2cap_conf_rfc *rfc)
3178 {
3179 if (chan->local_amp_id != AMP_ID_BREDR && chan->hs_hcon) {
3180 u64 ertm_to = chan->hs_hcon->hdev->amp_be_flush_to;
3181
3182 /* Class 1 devices have must have ERTM timeouts
3183 * exceeding the Link Supervision Timeout. The
3184 * default Link Supervision Timeout for AMP
3185 * controllers is 10 seconds.
3186 *
3187 * Class 1 devices use 0xffffffff for their
3188 * best-effort flush timeout, so the clamping logic
3189 * will result in a timeout that meets the above
3190 * requirement. ERTM timeouts are 16-bit values, so
3191 * the maximum timeout is 65.535 seconds.
3192 */
3193
3194 /* Convert timeout to milliseconds and round */
3195 ertm_to = DIV_ROUND_UP_ULL(ertm_to, 1000);
3196
3197 /* This is the recommended formula for class 2 devices
3198 * that start ERTM timers when packets are sent to the
3199 * controller.
3200 */
3201 ertm_to = 3 * ertm_to + 500;
3202
3203 if (ertm_to > 0xffff)
3204 ertm_to = 0xffff;
3205
3206 rfc->retrans_timeout = cpu_to_le16((u16) ertm_to);
3207 rfc->monitor_timeout = rfc->retrans_timeout;
3208 } else {
3209 rfc->retrans_timeout = cpu_to_le16(L2CAP_DEFAULT_RETRANS_TO);
3210 rfc->monitor_timeout = cpu_to_le16(L2CAP_DEFAULT_MONITOR_TO);
3211 }
3212 }
3213
3214 static inline void l2cap_txwin_setup(struct l2cap_chan *chan)
3215 {
3216 if (chan->tx_win > L2CAP_DEFAULT_TX_WINDOW &&
3217 __l2cap_ews_supported(chan->conn)) {
3218 /* use extended control field */
3219 set_bit(FLAG_EXT_CTRL, &chan->flags);
3220 chan->tx_win_max = L2CAP_DEFAULT_EXT_WINDOW;
3221 } else {
3222 chan->tx_win = min_t(u16, chan->tx_win,
3223 L2CAP_DEFAULT_TX_WINDOW);
3224 chan->tx_win_max = L2CAP_DEFAULT_TX_WINDOW;
3225 }
3226 chan->ack_win = chan->tx_win;
3227 }
3228
3229 static int l2cap_build_conf_req(struct l2cap_chan *chan, void *data, size_t data_size)
3230 {
3231 struct l2cap_conf_req *req = data;
3232 struct l2cap_conf_rfc rfc = { .mode = chan->mode };
3233 void *ptr = req->data;
3234 void *endptr = data + data_size;
3235 u16 size;
3236
3237 BT_DBG("chan %p", chan);
3238
3239 if (chan->num_conf_req || chan->num_conf_rsp)
3240 goto done;
3241
3242 switch (chan->mode) {
3243 case L2CAP_MODE_STREAMING:
3244 case L2CAP_MODE_ERTM:
3245 if (test_bit(CONF_STATE2_DEVICE, &chan->conf_state))
3246 break;
3247
3248 if (__l2cap_efs_supported(chan->conn))
3249 set_bit(FLAG_EFS_ENABLE, &chan->flags);
3250
3251 /* fall through */
3252 default:
3253 chan->mode = l2cap_select_mode(rfc.mode, chan->conn->feat_mask);
3254 break;
3255 }
3256
3257 done:
3258 if (chan->imtu != L2CAP_DEFAULT_MTU)
3259 l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->imtu, endptr - ptr);
3260
3261 switch (chan->mode) {
3262 case L2CAP_MODE_BASIC:
3263 if (disable_ertm)
3264 break;
3265
3266 if (!(chan->conn->feat_mask & L2CAP_FEAT_ERTM) &&
3267 !(chan->conn->feat_mask & L2CAP_FEAT_STREAMING))
3268 break;
3269
3270 rfc.mode = L2CAP_MODE_BASIC;
3271 rfc.txwin_size = 0;
3272 rfc.max_transmit = 0;
3273 rfc.retrans_timeout = 0;
3274 rfc.monitor_timeout = 0;
3275 rfc.max_pdu_size = 0;
3276
3277 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3278 (unsigned long) &rfc, endptr - ptr);
3279 break;
3280
3281 case L2CAP_MODE_ERTM:
3282 rfc.mode = L2CAP_MODE_ERTM;
3283 rfc.max_transmit = chan->max_tx;
3284
3285 __l2cap_set_ertm_timeouts(chan, &rfc);
3286
3287 size = min_t(u16, L2CAP_DEFAULT_MAX_PDU_SIZE, chan->conn->mtu -
3288 L2CAP_EXT_HDR_SIZE - L2CAP_SDULEN_SIZE -
3289 L2CAP_FCS_SIZE);
3290 rfc.max_pdu_size = cpu_to_le16(size);
3291
3292 l2cap_txwin_setup(chan);
3293
3294 rfc.txwin_size = min_t(u16, chan->tx_win,
3295 L2CAP_DEFAULT_TX_WINDOW);
3296
3297 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3298 (unsigned long) &rfc, endptr - ptr);
3299
3300 if (test_bit(FLAG_EFS_ENABLE, &chan->flags))
3301 l2cap_add_opt_efs(&ptr, chan, endptr - ptr);
3302
3303 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
3304 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EWS, 2,
3305 chan->tx_win, endptr - ptr);
3306
3307 if (chan->conn->feat_mask & L2CAP_FEAT_FCS)
3308 if (chan->fcs == L2CAP_FCS_NONE ||
3309 test_bit(CONF_RECV_NO_FCS, &chan->conf_state)) {
3310 chan->fcs = L2CAP_FCS_NONE;
3311 l2cap_add_conf_opt(&ptr, L2CAP_CONF_FCS, 1,
3312 chan->fcs, endptr - ptr);
3313 }
3314 break;
3315
3316 case L2CAP_MODE_STREAMING:
3317 l2cap_txwin_setup(chan);
3318 rfc.mode = L2CAP_MODE_STREAMING;
3319 rfc.txwin_size = 0;
3320 rfc.max_transmit = 0;
3321 rfc.retrans_timeout = 0;
3322 rfc.monitor_timeout = 0;
3323
3324 size = min_t(u16, L2CAP_DEFAULT_MAX_PDU_SIZE, chan->conn->mtu -
3325 L2CAP_EXT_HDR_SIZE - L2CAP_SDULEN_SIZE -
3326 L2CAP_FCS_SIZE);
3327 rfc.max_pdu_size = cpu_to_le16(size);
3328
3329 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3330 (unsigned long) &rfc, endptr - ptr);
3331
3332 if (test_bit(FLAG_EFS_ENABLE, &chan->flags))
3333 l2cap_add_opt_efs(&ptr, chan, endptr - ptr);
3334
3335 if (chan->conn->feat_mask & L2CAP_FEAT_FCS)
3336 if (chan->fcs == L2CAP_FCS_NONE ||
3337 test_bit(CONF_RECV_NO_FCS, &chan->conf_state)) {
3338 chan->fcs = L2CAP_FCS_NONE;
3339 l2cap_add_conf_opt(&ptr, L2CAP_CONF_FCS, 1,
3340 chan->fcs, endptr - ptr);
3341 }
3342 break;
3343 }
3344
3345 req->dcid = cpu_to_le16(chan->dcid);
3346 req->flags = cpu_to_le16(0);
3347
3348 return ptr - data;
3349 }
3350
3351 static int l2cap_parse_conf_req(struct l2cap_chan *chan, void *data, size_t data_size)
3352 {
3353 struct l2cap_conf_rsp *rsp = data;
3354 void *ptr = rsp->data;
3355 void *endptr = data + data_size;
3356 void *req = chan->conf_req;
3357 int len = chan->conf_len;
3358 int type, hint, olen;
3359 unsigned long val;
3360 struct l2cap_conf_rfc rfc = { .mode = L2CAP_MODE_BASIC };
3361 struct l2cap_conf_efs efs;
3362 u8 remote_efs = 0;
3363 u16 mtu = L2CAP_DEFAULT_MTU;
3364 u16 result = L2CAP_CONF_SUCCESS;
3365 u16 size;
3366
3367 BT_DBG("chan %p", chan);
3368
3369 while (len >= L2CAP_CONF_OPT_SIZE) {
3370 len -= l2cap_get_conf_opt(&req, &type, &olen, &val);
3371 if (len < 0)
3372 break;
3373
3374 hint = type & L2CAP_CONF_HINT;
3375 type &= L2CAP_CONF_MASK;
3376
3377 switch (type) {
3378 case L2CAP_CONF_MTU:
3379 if (olen != 2)
3380 break;
3381 mtu = val;
3382 break;
3383
3384 case L2CAP_CONF_FLUSH_TO:
3385 if (olen != 2)
3386 break;
3387 chan->flush_to = val;
3388 break;
3389
3390 case L2CAP_CONF_QOS:
3391 break;
3392
3393 case L2CAP_CONF_RFC:
3394 if (olen != sizeof(rfc))
3395 break;
3396 memcpy(&rfc, (void *) val, olen);
3397 break;
3398
3399 case L2CAP_CONF_FCS:
3400 if (olen != 1)
3401 break;
3402 if (val == L2CAP_FCS_NONE)
3403 set_bit(CONF_RECV_NO_FCS, &chan->conf_state);
3404 break;
3405
3406 case L2CAP_CONF_EFS:
3407 if (olen != sizeof(efs))
3408 break;
3409 remote_efs = 1;
3410 memcpy(&efs, (void *) val, olen);
3411 break;
3412
3413 case L2CAP_CONF_EWS:
3414 if (olen != 2)
3415 break;
3416 if (!(chan->conn->local_fixed_chan & L2CAP_FC_A2MP))
3417 return -ECONNREFUSED;
3418 set_bit(FLAG_EXT_CTRL, &chan->flags);
3419 set_bit(CONF_EWS_RECV, &chan->conf_state);
3420 chan->tx_win_max = L2CAP_DEFAULT_EXT_WINDOW;
3421 chan->remote_tx_win = val;
3422 break;
3423
3424 default:
3425 if (hint)
3426 break;
3427 result = L2CAP_CONF_UNKNOWN;
3428 *((u8 *) ptr++) = type;
3429 break;
3430 }
3431 }
3432
3433 if (chan->num_conf_rsp || chan->num_conf_req > 1)
3434 goto done;
3435
3436 switch (chan->mode) {
3437 case L2CAP_MODE_STREAMING:
3438 case L2CAP_MODE_ERTM:
3439 if (!test_bit(CONF_STATE2_DEVICE, &chan->conf_state)) {
3440 chan->mode = l2cap_select_mode(rfc.mode,
3441 chan->conn->feat_mask);
3442 break;
3443 }
3444
3445 if (remote_efs) {
3446 if (__l2cap_efs_supported(chan->conn))
3447 set_bit(FLAG_EFS_ENABLE, &chan->flags);
3448 else
3449 return -ECONNREFUSED;
3450 }
3451
3452 if (chan->mode != rfc.mode)
3453 return -ECONNREFUSED;
3454
3455 break;
3456 }
3457
3458 done:
3459 if (chan->mode != rfc.mode) {
3460 result = L2CAP_CONF_UNACCEPT;
3461 rfc.mode = chan->mode;
3462
3463 if (chan->num_conf_rsp == 1)
3464 return -ECONNREFUSED;
3465
3466 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3467 (unsigned long) &rfc, endptr - ptr);
3468 }
3469
3470 if (result == L2CAP_CONF_SUCCESS) {
3471 /* Configure output options and let the other side know
3472 * which ones we don't like. */
3473
3474 if (mtu < L2CAP_DEFAULT_MIN_MTU)
3475 result = L2CAP_CONF_UNACCEPT;
3476 else {
3477 chan->omtu = mtu;
3478 set_bit(CONF_MTU_DONE, &chan->conf_state);
3479 }
3480 l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->omtu, endptr - ptr);
3481
3482 if (remote_efs) {
3483 if (chan->local_stype != L2CAP_SERV_NOTRAFIC &&
3484 efs.stype != L2CAP_SERV_NOTRAFIC &&
3485 efs.stype != chan->local_stype) {
3486
3487 result = L2CAP_CONF_UNACCEPT;
3488
3489 if (chan->num_conf_req >= 1)
3490 return -ECONNREFUSED;
3491
3492 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS,
3493 sizeof(efs),
3494 (unsigned long) &efs, endptr - ptr);
3495 } else {
3496 /* Send PENDING Conf Rsp */
3497 result = L2CAP_CONF_PENDING;
3498 set_bit(CONF_LOC_CONF_PEND, &chan->conf_state);
3499 }
3500 }
3501
3502 switch (rfc.mode) {
3503 case L2CAP_MODE_BASIC:
3504 chan->fcs = L2CAP_FCS_NONE;
3505 set_bit(CONF_MODE_DONE, &chan->conf_state);
3506 break;
3507
3508 case L2CAP_MODE_ERTM:
3509 if (!test_bit(CONF_EWS_RECV, &chan->conf_state))
3510 chan->remote_tx_win = rfc.txwin_size;
3511 else
3512 rfc.txwin_size = L2CAP_DEFAULT_TX_WINDOW;
3513
3514 chan->remote_max_tx = rfc.max_transmit;
3515
3516 size = min_t(u16, le16_to_cpu(rfc.max_pdu_size),
3517 chan->conn->mtu - L2CAP_EXT_HDR_SIZE -
3518 L2CAP_SDULEN_SIZE - L2CAP_FCS_SIZE);
3519 rfc.max_pdu_size = cpu_to_le16(size);
3520 chan->remote_mps = size;
3521
3522 __l2cap_set_ertm_timeouts(chan, &rfc);
3523
3524 set_bit(CONF_MODE_DONE, &chan->conf_state);
3525
3526 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC,
3527 sizeof(rfc), (unsigned long) &rfc, endptr - ptr);
3528
3529 if (test_bit(FLAG_EFS_ENABLE, &chan->flags)) {
3530 chan->remote_id = efs.id;
3531 chan->remote_stype = efs.stype;
3532 chan->remote_msdu = le16_to_cpu(efs.msdu);
3533 chan->remote_flush_to =
3534 le32_to_cpu(efs.flush_to);
3535 chan->remote_acc_lat =
3536 le32_to_cpu(efs.acc_lat);
3537 chan->remote_sdu_itime =
3538 le32_to_cpu(efs.sdu_itime);
3539 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS,
3540 sizeof(efs),
3541 (unsigned long) &efs, endptr - ptr);
3542 }
3543 break;
3544
3545 case L2CAP_MODE_STREAMING:
3546 size = min_t(u16, le16_to_cpu(rfc.max_pdu_size),
3547 chan->conn->mtu - L2CAP_EXT_HDR_SIZE -
3548 L2CAP_SDULEN_SIZE - L2CAP_FCS_SIZE);
3549 rfc.max_pdu_size = cpu_to_le16(size);
3550 chan->remote_mps = size;
3551
3552 set_bit(CONF_MODE_DONE, &chan->conf_state);
3553
3554 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3555 (unsigned long) &rfc, endptr - ptr);
3556
3557 break;
3558
3559 default:
3560 result = L2CAP_CONF_UNACCEPT;
3561
3562 memset(&rfc, 0, sizeof(rfc));
3563 rfc.mode = chan->mode;
3564 }
3565
3566 if (result == L2CAP_CONF_SUCCESS)
3567 set_bit(CONF_OUTPUT_DONE, &chan->conf_state);
3568 }
3569 rsp->scid = cpu_to_le16(chan->dcid);
3570 rsp->result = cpu_to_le16(result);
3571 rsp->flags = cpu_to_le16(0);
3572
3573 return ptr - data;
3574 }
3575
3576 static int l2cap_parse_conf_rsp(struct l2cap_chan *chan, void *rsp, int len,
3577 void *data, size_t size, u16 *result)
3578 {
3579 struct l2cap_conf_req *req = data;
3580 void *ptr = req->data;
3581 void *endptr = data + size;
3582 int type, olen;
3583 unsigned long val;
3584 struct l2cap_conf_rfc rfc = { .mode = L2CAP_MODE_BASIC };
3585 struct l2cap_conf_efs efs;
3586
3587 BT_DBG("chan %p, rsp %p, len %d, req %p", chan, rsp, len, data);
3588
3589 while (len >= L2CAP_CONF_OPT_SIZE) {
3590 len -= l2cap_get_conf_opt(&rsp, &type, &olen, &val);
3591 if (len < 0)
3592 break;
3593
3594 switch (type) {
3595 case L2CAP_CONF_MTU:
3596 if (olen != 2)
3597 break;
3598 if (val < L2CAP_DEFAULT_MIN_MTU) {
3599 *result = L2CAP_CONF_UNACCEPT;
3600 chan->imtu = L2CAP_DEFAULT_MIN_MTU;
3601 } else
3602 chan->imtu = val;
3603 l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->imtu,
3604 endptr - ptr);
3605 break;
3606
3607 case L2CAP_CONF_FLUSH_TO:
3608 if (olen != 2)
3609 break;
3610 chan->flush_to = val;
3611 l2cap_add_conf_opt(&ptr, L2CAP_CONF_FLUSH_TO, 2,
3612 chan->flush_to, endptr - ptr);
3613 break;
3614
3615 case L2CAP_CONF_RFC:
3616 if (olen != sizeof(rfc))
3617 break;
3618 memcpy(&rfc, (void *)val, olen);
3619 if (test_bit(CONF_STATE2_DEVICE, &chan->conf_state) &&
3620 rfc.mode != chan->mode)
3621 return -ECONNREFUSED;
3622 chan->fcs = 0;
3623 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3624 (unsigned long) &rfc, endptr - ptr);
3625 break;
3626
3627 case L2CAP_CONF_EWS:
3628 if (olen != 2)
3629 break;
3630 chan->ack_win = min_t(u16, val, chan->ack_win);
3631 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EWS, 2,
3632 chan->tx_win, endptr - ptr);
3633 break;
3634
3635 case L2CAP_CONF_EFS:
3636 if (olen != sizeof(efs))
3637 break;
3638 memcpy(&efs, (void *)val, olen);
3639 if (chan->local_stype != L2CAP_SERV_NOTRAFIC &&
3640 efs.stype != L2CAP_SERV_NOTRAFIC &&
3641 efs.stype != chan->local_stype)
3642 return -ECONNREFUSED;
3643 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS, sizeof(efs),
3644 (unsigned long) &efs, endptr - ptr);
3645 break;
3646
3647 case L2CAP_CONF_FCS:
3648 if (olen != 1)
3649 break;
3650 if (*result == L2CAP_CONF_PENDING)
3651 if (val == L2CAP_FCS_NONE)
3652 set_bit(CONF_RECV_NO_FCS,
3653 &chan->conf_state);
3654 break;
3655 }
3656 }
3657
3658 if (chan->mode == L2CAP_MODE_BASIC && chan->mode != rfc.mode)
3659 return -ECONNREFUSED;
3660
3661 chan->mode = rfc.mode;
3662
3663 if (*result == L2CAP_CONF_SUCCESS || *result == L2CAP_CONF_PENDING) {
3664 switch (rfc.mode) {
3665 case L2CAP_MODE_ERTM:
3666 chan->retrans_timeout = le16_to_cpu(rfc.retrans_timeout);
3667 chan->monitor_timeout = le16_to_cpu(rfc.monitor_timeout);
3668 chan->mps = le16_to_cpu(rfc.max_pdu_size);
3669 if (!test_bit(FLAG_EXT_CTRL, &chan->flags))
3670 chan->ack_win = min_t(u16, chan->ack_win,
3671 rfc.txwin_size);
3672
3673 if (test_bit(FLAG_EFS_ENABLE, &chan->flags)) {
3674 chan->local_msdu = le16_to_cpu(efs.msdu);
3675 chan->local_sdu_itime =
3676 le32_to_cpu(efs.sdu_itime);
3677 chan->local_acc_lat = le32_to_cpu(efs.acc_lat);
3678 chan->local_flush_to =
3679 le32_to_cpu(efs.flush_to);
3680 }
3681 break;
3682
3683 case L2CAP_MODE_STREAMING:
3684 chan->mps = le16_to_cpu(rfc.max_pdu_size);
3685 }
3686 }
3687
3688 req->dcid = cpu_to_le16(chan->dcid);
3689 req->flags = cpu_to_le16(0);
3690
3691 return ptr - data;
3692 }
3693
3694 static int l2cap_build_conf_rsp(struct l2cap_chan *chan, void *data,
3695 u16 result, u16 flags)
3696 {
3697 struct l2cap_conf_rsp *rsp = data;
3698 void *ptr = rsp->data;
3699
3700 BT_DBG("chan %p", chan);
3701
3702 rsp->scid = cpu_to_le16(chan->dcid);
3703 rsp->result = cpu_to_le16(result);
3704 rsp->flags = cpu_to_le16(flags);
3705
3706 return ptr - data;
3707 }
3708
3709 void __l2cap_le_connect_rsp_defer(struct l2cap_chan *chan)
3710 {
3711 struct l2cap_le_conn_rsp rsp;
3712 struct l2cap_conn *conn = chan->conn;
3713
3714 BT_DBG("chan %p", chan);
3715
3716 rsp.dcid = cpu_to_le16(chan->scid);
3717 rsp.mtu = cpu_to_le16(chan->imtu);
3718 rsp.mps = cpu_to_le16(chan->mps);
3719 rsp.credits = cpu_to_le16(chan->rx_credits);
3720 rsp.result = cpu_to_le16(L2CAP_CR_LE_SUCCESS);
3721
3722 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CONN_RSP, sizeof(rsp),
3723 &rsp);
3724 }
3725
3726 void __l2cap_connect_rsp_defer(struct l2cap_chan *chan)
3727 {
3728 struct l2cap_conn_rsp rsp;
3729 struct l2cap_conn *conn = chan->conn;
3730 u8 buf[128];
3731 u8 rsp_code;
3732
3733 rsp.scid = cpu_to_le16(chan->dcid);
3734 rsp.dcid = cpu_to_le16(chan->scid);
3735 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
3736 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
3737
3738 if (chan->hs_hcon)
3739 rsp_code = L2CAP_CREATE_CHAN_RSP;
3740 else
3741 rsp_code = L2CAP_CONN_RSP;
3742
3743 BT_DBG("chan %p rsp_code %u", chan, rsp_code);
3744
3745 l2cap_send_cmd(conn, chan->ident, rsp_code, sizeof(rsp), &rsp);
3746
3747 if (test_and_set_bit(CONF_REQ_SENT, &chan->conf_state))
3748 return;
3749
3750 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
3751 l2cap_build_conf_req(chan, buf, sizeof(buf)), buf);
3752 chan->num_conf_req++;
3753 }
3754
3755 static void l2cap_conf_rfc_get(struct l2cap_chan *chan, void *rsp, int len)
3756 {
3757 int type, olen;
3758 unsigned long val;
3759 /* Use sane default values in case a misbehaving remote device
3760 * did not send an RFC or extended window size option.
3761 */
3762 u16 txwin_ext = chan->ack_win;
3763 struct l2cap_conf_rfc rfc = {
3764 .mode = chan->mode,
3765 .retrans_timeout = cpu_to_le16(L2CAP_DEFAULT_RETRANS_TO),
3766 .monitor_timeout = cpu_to_le16(L2CAP_DEFAULT_MONITOR_TO),
3767 .max_pdu_size = cpu_to_le16(chan->imtu),
3768 .txwin_size = min_t(u16, chan->ack_win, L2CAP_DEFAULT_TX_WINDOW),
3769 };
3770
3771 BT_DBG("chan %p, rsp %p, len %d", chan, rsp, len);
3772
3773 if ((chan->mode != L2CAP_MODE_ERTM) && (chan->mode != L2CAP_MODE_STREAMING))
3774 return;
3775
3776 while (len >= L2CAP_CONF_OPT_SIZE) {
3777 len -= l2cap_get_conf_opt(&rsp, &type, &olen, &val);
3778 if (len < 0)
3779 break;
3780
3781 switch (type) {
3782 case L2CAP_CONF_RFC:
3783 if (olen != sizeof(rfc))
3784 break;
3785 memcpy(&rfc, (void *)val, olen);
3786 break;
3787 case L2CAP_CONF_EWS:
3788 if (olen != 2)
3789 break;
3790 txwin_ext = val;
3791 break;
3792 }
3793 }
3794
3795 switch (rfc.mode) {
3796 case L2CAP_MODE_ERTM:
3797 chan->retrans_timeout = le16_to_cpu(rfc.retrans_timeout);
3798 chan->monitor_timeout = le16_to_cpu(rfc.monitor_timeout);
3799 chan->mps = le16_to_cpu(rfc.max_pdu_size);
3800 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
3801 chan->ack_win = min_t(u16, chan->ack_win, txwin_ext);
3802 else
3803 chan->ack_win = min_t(u16, chan->ack_win,
3804 rfc.txwin_size);
3805 break;
3806 case L2CAP_MODE_STREAMING:
3807 chan->mps = le16_to_cpu(rfc.max_pdu_size);
3808 }
3809 }
3810
3811 static inline int l2cap_command_rej(struct l2cap_conn *conn,
3812 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
3813 u8 *data)
3814 {
3815 struct l2cap_cmd_rej_unk *rej = (struct l2cap_cmd_rej_unk *) data;
3816
3817 if (cmd_len < sizeof(*rej))
3818 return -EPROTO;
3819
3820 if (rej->reason != L2CAP_REJ_NOT_UNDERSTOOD)
3821 return 0;
3822
3823 if ((conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT) &&
3824 cmd->ident == conn->info_ident) {
3825 cancel_delayed_work(&conn->info_timer);
3826
3827 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
3828 conn->info_ident = 0;
3829
3830 l2cap_conn_start(conn);
3831 }
3832
3833 return 0;
3834 }
3835
3836 static struct l2cap_chan *l2cap_connect(struct l2cap_conn *conn,
3837 struct l2cap_cmd_hdr *cmd,
3838 u8 *data, u8 rsp_code, u8 amp_id)
3839 {
3840 struct l2cap_conn_req *req = (struct l2cap_conn_req *) data;
3841 struct l2cap_conn_rsp rsp;
3842 struct l2cap_chan *chan = NULL, *pchan;
3843 int result, status = L2CAP_CS_NO_INFO;
3844
3845 u16 dcid = 0, scid = __le16_to_cpu(req->scid);
3846 __le16 psm = req->psm;
3847
3848 BT_DBG("psm 0x%2.2x scid 0x%4.4x", __le16_to_cpu(psm), scid);
3849
3850 /* Check if we have socket listening on psm */
3851 pchan = l2cap_global_chan_by_psm(BT_LISTEN, psm, &conn->hcon->src,
3852 &conn->hcon->dst, ACL_LINK);
3853 if (!pchan) {
3854 result = L2CAP_CR_BAD_PSM;
3855 goto sendresp;
3856 }
3857
3858 mutex_lock(&conn->chan_lock);
3859 l2cap_chan_lock(pchan);
3860
3861 /* Check if the ACL is secure enough (if not SDP) */
3862 if (psm != cpu_to_le16(L2CAP_PSM_SDP) &&
3863 !hci_conn_check_link_mode(conn->hcon)) {
3864 conn->disc_reason = HCI_ERROR_AUTH_FAILURE;
3865 result = L2CAP_CR_SEC_BLOCK;
3866 goto response;
3867 }
3868
3869 result = L2CAP_CR_NO_MEM;
3870
3871 /* Check for valid dynamic CID range (as per Erratum 3253) */
3872 if (scid < L2CAP_CID_DYN_START || scid > L2CAP_CID_DYN_END) {
3873 result = L2CAP_CR_INVALID_SCID;
3874 goto response;
3875 }
3876
3877 /* Check if we already have channel with that dcid */
3878 if (__l2cap_get_chan_by_dcid(conn, scid)) {
3879 result = L2CAP_CR_SCID_IN_USE;
3880 goto response;
3881 }
3882
3883 chan = pchan->ops->new_connection(pchan);
3884 if (!chan)
3885 goto response;
3886
3887 /* For certain devices (ex: HID mouse), support for authentication,
3888 * pairing and bonding is optional. For such devices, inorder to avoid
3889 * the ACL alive for too long after L2CAP disconnection, reset the ACL
3890 * disc_timeout back to HCI_DISCONN_TIMEOUT during L2CAP connect.
3891 */
3892 conn->hcon->disc_timeout = HCI_DISCONN_TIMEOUT;
3893
3894 bacpy(&chan->src, &conn->hcon->src);
3895 bacpy(&chan->dst, &conn->hcon->dst);
3896 chan->src_type = bdaddr_src_type(conn->hcon);
3897 chan->dst_type = bdaddr_dst_type(conn->hcon);
3898 chan->psm = psm;
3899 chan->dcid = scid;
3900 chan->local_amp_id = amp_id;
3901
3902 __l2cap_chan_add(conn, chan);
3903
3904 dcid = chan->scid;
3905
3906 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
3907
3908 chan->ident = cmd->ident;
3909
3910 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE) {
3911 if (l2cap_chan_check_security(chan, false)) {
3912 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
3913 l2cap_state_change(chan, BT_CONNECT2);
3914 result = L2CAP_CR_PEND;
3915 status = L2CAP_CS_AUTHOR_PEND;
3916 chan->ops->defer(chan);
3917 } else {
3918 /* Force pending result for AMP controllers.
3919 * The connection will succeed after the
3920 * physical link is up.
3921 */
3922 if (amp_id == AMP_ID_BREDR) {
3923 l2cap_state_change(chan, BT_CONFIG);
3924 result = L2CAP_CR_SUCCESS;
3925 } else {
3926 l2cap_state_change(chan, BT_CONNECT2);
3927 result = L2CAP_CR_PEND;
3928 }
3929 status = L2CAP_CS_NO_INFO;
3930 }
3931 } else {
3932 l2cap_state_change(chan, BT_CONNECT2);
3933 result = L2CAP_CR_PEND;
3934 status = L2CAP_CS_AUTHEN_PEND;
3935 }
3936 } else {
3937 l2cap_state_change(chan, BT_CONNECT2);
3938 result = L2CAP_CR_PEND;
3939 status = L2CAP_CS_NO_INFO;
3940 }
3941
3942 response:
3943 l2cap_chan_unlock(pchan);
3944 mutex_unlock(&conn->chan_lock);
3945 l2cap_chan_put(pchan);
3946
3947 sendresp:
3948 rsp.scid = cpu_to_le16(scid);
3949 rsp.dcid = cpu_to_le16(dcid);
3950 rsp.result = cpu_to_le16(result);
3951 rsp.status = cpu_to_le16(status);
3952 l2cap_send_cmd(conn, cmd->ident, rsp_code, sizeof(rsp), &rsp);
3953
3954 if (result == L2CAP_CR_PEND && status == L2CAP_CS_NO_INFO) {
3955 struct l2cap_info_req info;
3956 info.type = cpu_to_le16(L2CAP_IT_FEAT_MASK);
3957
3958 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_SENT;
3959 conn->info_ident = l2cap_get_ident(conn);
3960
3961 schedule_delayed_work(&conn->info_timer, L2CAP_INFO_TIMEOUT);
3962
3963 l2cap_send_cmd(conn, conn->info_ident, L2CAP_INFO_REQ,
3964 sizeof(info), &info);
3965 }
3966
3967 if (chan && !test_bit(CONF_REQ_SENT, &chan->conf_state) &&
3968 result == L2CAP_CR_SUCCESS) {
3969 u8 buf[128];
3970 set_bit(CONF_REQ_SENT, &chan->conf_state);
3971 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
3972 l2cap_build_conf_req(chan, buf, sizeof(buf)), buf);
3973 chan->num_conf_req++;
3974 }
3975
3976 return chan;
3977 }
3978
3979 static int l2cap_connect_req(struct l2cap_conn *conn,
3980 struct l2cap_cmd_hdr *cmd, u16 cmd_len, u8 *data)
3981 {
3982 struct hci_dev *hdev = conn->hcon->hdev;
3983 struct hci_conn *hcon = conn->hcon;
3984
3985 if (cmd_len < sizeof(struct l2cap_conn_req))
3986 return -EPROTO;
3987
3988 hci_dev_lock(hdev);
3989 if (hci_dev_test_flag(hdev, HCI_MGMT) &&
3990 !test_and_set_bit(HCI_CONN_MGMT_CONNECTED, &hcon->flags))
3991 mgmt_device_connected(hdev, hcon, 0, NULL, 0);
3992 hci_dev_unlock(hdev);
3993
3994 l2cap_connect(conn, cmd, data, L2CAP_CONN_RSP, 0);
3995 return 0;
3996 }
3997
3998 static int l2cap_connect_create_rsp(struct l2cap_conn *conn,
3999 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4000 u8 *data)
4001 {
4002 struct l2cap_conn_rsp *rsp = (struct l2cap_conn_rsp *) data;
4003 u16 scid, dcid, result, status;
4004 struct l2cap_chan *chan;
4005 u8 req[128];
4006 int err;
4007
4008 if (cmd_len < sizeof(*rsp))
4009 return -EPROTO;
4010
4011 scid = __le16_to_cpu(rsp->scid);
4012 dcid = __le16_to_cpu(rsp->dcid);
4013 result = __le16_to_cpu(rsp->result);
4014 status = __le16_to_cpu(rsp->status);
4015
4016 BT_DBG("dcid 0x%4.4x scid 0x%4.4x result 0x%2.2x status 0x%2.2x",
4017 dcid, scid, result, status);
4018
4019 mutex_lock(&conn->chan_lock);
4020
4021 if (scid) {
4022 chan = __l2cap_get_chan_by_scid(conn, scid);
4023 if (!chan) {
4024 err = -EBADSLT;
4025 goto unlock;
4026 }
4027 } else {
4028 chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
4029 if (!chan) {
4030 err = -EBADSLT;
4031 goto unlock;
4032 }
4033 }
4034
4035 err = 0;
4036
4037 l2cap_chan_lock(chan);
4038
4039 switch (result) {
4040 case L2CAP_CR_SUCCESS:
4041 l2cap_state_change(chan, BT_CONFIG);
4042 chan->ident = 0;
4043 chan->dcid = dcid;
4044 clear_bit(CONF_CONNECT_PEND, &chan->conf_state);
4045
4046 if (test_and_set_bit(CONF_REQ_SENT, &chan->conf_state))
4047 break;
4048
4049 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
4050 l2cap_build_conf_req(chan, req, sizeof(req)), req);
4051 chan->num_conf_req++;
4052 break;
4053
4054 case L2CAP_CR_PEND:
4055 set_bit(CONF_CONNECT_PEND, &chan->conf_state);
4056 break;
4057
4058 default:
4059 l2cap_chan_del(chan, ECONNREFUSED);
4060 break;
4061 }
4062
4063 l2cap_chan_unlock(chan);
4064
4065 unlock:
4066 mutex_unlock(&conn->chan_lock);
4067
4068 return err;
4069 }
4070
4071 static inline void set_default_fcs(struct l2cap_chan *chan)
4072 {
4073 /* FCS is enabled only in ERTM or streaming mode, if one or both
4074 * sides request it.
4075 */
4076 if (chan->mode != L2CAP_MODE_ERTM && chan->mode != L2CAP_MODE_STREAMING)
4077 chan->fcs = L2CAP_FCS_NONE;
4078 else if (!test_bit(CONF_RECV_NO_FCS, &chan->conf_state))
4079 chan->fcs = L2CAP_FCS_CRC16;
4080 }
4081
4082 static void l2cap_send_efs_conf_rsp(struct l2cap_chan *chan, void *data,
4083 u8 ident, u16 flags)
4084 {
4085 struct l2cap_conn *conn = chan->conn;
4086
4087 BT_DBG("conn %p chan %p ident %d flags 0x%4.4x", conn, chan, ident,
4088 flags);
4089
4090 clear_bit(CONF_LOC_CONF_PEND, &chan->conf_state);
4091 set_bit(CONF_OUTPUT_DONE, &chan->conf_state);
4092
4093 l2cap_send_cmd(conn, ident, L2CAP_CONF_RSP,
4094 l2cap_build_conf_rsp(chan, data,
4095 L2CAP_CONF_SUCCESS, flags), data);
4096 }
4097
4098 static void cmd_reject_invalid_cid(struct l2cap_conn *conn, u8 ident,
4099 u16 scid, u16 dcid)
4100 {
4101 struct l2cap_cmd_rej_cid rej;
4102
4103 rej.reason = cpu_to_le16(L2CAP_REJ_INVALID_CID);
4104 rej.scid = __cpu_to_le16(scid);
4105 rej.dcid = __cpu_to_le16(dcid);
4106
4107 l2cap_send_cmd(conn, ident, L2CAP_COMMAND_REJ, sizeof(rej), &rej);
4108 }
4109
4110 static inline int l2cap_config_req(struct l2cap_conn *conn,
4111 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4112 u8 *data)
4113 {
4114 struct l2cap_conf_req *req = (struct l2cap_conf_req *) data;
4115 u16 dcid, flags;
4116 u8 rsp[64];
4117 struct l2cap_chan *chan;
4118 int len, err = 0;
4119
4120 if (cmd_len < sizeof(*req))
4121 return -EPROTO;
4122
4123 dcid = __le16_to_cpu(req->dcid);
4124 flags = __le16_to_cpu(req->flags);
4125
4126 BT_DBG("dcid 0x%4.4x flags 0x%2.2x", dcid, flags);
4127
4128 chan = l2cap_get_chan_by_scid(conn, dcid);
4129 if (!chan) {
4130 cmd_reject_invalid_cid(conn, cmd->ident, dcid, 0);
4131 return 0;
4132 }
4133
4134 if (chan->state != BT_CONFIG && chan->state != BT_CONNECT2) {
4135 cmd_reject_invalid_cid(conn, cmd->ident, chan->scid,
4136 chan->dcid);
4137 goto unlock;
4138 }
4139
4140 /* Reject if config buffer is too small. */
4141 len = cmd_len - sizeof(*req);
4142 if (chan->conf_len + len > sizeof(chan->conf_req)) {
4143 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP,
4144 l2cap_build_conf_rsp(chan, rsp,
4145 L2CAP_CONF_REJECT, flags), rsp);
4146 goto unlock;
4147 }
4148
4149 /* Store config. */
4150 memcpy(chan->conf_req + chan->conf_len, req->data, len);
4151 chan->conf_len += len;
4152
4153 if (flags & L2CAP_CONF_FLAG_CONTINUATION) {
4154 /* Incomplete config. Send empty response. */
4155 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP,
4156 l2cap_build_conf_rsp(chan, rsp,
4157 L2CAP_CONF_SUCCESS, flags), rsp);
4158 goto unlock;
4159 }
4160
4161 /* Complete config. */
4162 len = l2cap_parse_conf_req(chan, rsp, sizeof(rsp));
4163 if (len < 0) {
4164 l2cap_send_disconn_req(chan, ECONNRESET);
4165 goto unlock;
4166 }
4167
4168 chan->ident = cmd->ident;
4169 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP, len, rsp);
4170 chan->num_conf_rsp++;
4171
4172 /* Reset config buffer. */
4173 chan->conf_len = 0;
4174
4175 if (!test_bit(CONF_OUTPUT_DONE, &chan->conf_state))
4176 goto unlock;
4177
4178 if (test_bit(CONF_INPUT_DONE, &chan->conf_state)) {
4179 set_default_fcs(chan);
4180
4181 if (chan->mode == L2CAP_MODE_ERTM ||
4182 chan->mode == L2CAP_MODE_STREAMING)
4183 err = l2cap_ertm_init(chan);
4184
4185 if (err < 0)
4186 l2cap_send_disconn_req(chan, -err);
4187 else
4188 l2cap_chan_ready(chan);
4189
4190 goto unlock;
4191 }
4192
4193 if (!test_and_set_bit(CONF_REQ_SENT, &chan->conf_state)) {
4194 u8 buf[64];
4195 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
4196 l2cap_build_conf_req(chan, buf, sizeof(buf)), buf);
4197 chan->num_conf_req++;
4198 }
4199
4200 /* Got Conf Rsp PENDING from remote side and assume we sent
4201 Conf Rsp PENDING in the code above */
4202 if (test_bit(CONF_REM_CONF_PEND, &chan->conf_state) &&
4203 test_bit(CONF_LOC_CONF_PEND, &chan->conf_state)) {
4204
4205 /* check compatibility */
4206
4207 /* Send rsp for BR/EDR channel */
4208 if (!chan->hs_hcon)
4209 l2cap_send_efs_conf_rsp(chan, rsp, cmd->ident, flags);
4210 else
4211 chan->ident = cmd->ident;
4212 }
4213
4214 unlock:
4215 l2cap_chan_unlock(chan);
4216 return err;
4217 }
4218
4219 static inline int l2cap_config_rsp(struct l2cap_conn *conn,
4220 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4221 u8 *data)
4222 {
4223 struct l2cap_conf_rsp *rsp = (struct l2cap_conf_rsp *)data;
4224 u16 scid, flags, result;
4225 struct l2cap_chan *chan;
4226 int len = cmd_len - sizeof(*rsp);
4227 int err = 0;
4228
4229 if (cmd_len < sizeof(*rsp))
4230 return -EPROTO;
4231
4232 scid = __le16_to_cpu(rsp->scid);
4233 flags = __le16_to_cpu(rsp->flags);
4234 result = __le16_to_cpu(rsp->result);
4235
4236 BT_DBG("scid 0x%4.4x flags 0x%2.2x result 0x%2.2x len %d", scid, flags,
4237 result, len);
4238
4239 chan = l2cap_get_chan_by_scid(conn, scid);
4240 if (!chan)
4241 return 0;
4242
4243 switch (result) {
4244 case L2CAP_CONF_SUCCESS:
4245 l2cap_conf_rfc_get(chan, rsp->data, len);
4246 clear_bit(CONF_REM_CONF_PEND, &chan->conf_state);
4247 break;
4248
4249 case L2CAP_CONF_PENDING:
4250 set_bit(CONF_REM_CONF_PEND, &chan->conf_state);
4251
4252 if (test_bit(CONF_LOC_CONF_PEND, &chan->conf_state)) {
4253 char buf[64];
4254
4255 len = l2cap_parse_conf_rsp(chan, rsp->data, len,
4256 buf, sizeof(buf), &result);
4257 if (len < 0) {
4258 l2cap_send_disconn_req(chan, ECONNRESET);
4259 goto done;
4260 }
4261
4262 if (!chan->hs_hcon) {
4263 l2cap_send_efs_conf_rsp(chan, buf, cmd->ident,
4264 0);
4265 } else {
4266 if (l2cap_check_efs(chan)) {
4267 amp_create_logical_link(chan);
4268 chan->ident = cmd->ident;
4269 }
4270 }
4271 }
4272 goto done;
4273
4274 case L2CAP_CONF_UNACCEPT:
4275 if (chan->num_conf_rsp <= L2CAP_CONF_MAX_CONF_RSP) {
4276 char req[64];
4277
4278 if (len > sizeof(req) - sizeof(struct l2cap_conf_req)) {
4279 l2cap_send_disconn_req(chan, ECONNRESET);
4280 goto done;
4281 }
4282
4283 /* throw out any old stored conf requests */
4284 result = L2CAP_CONF_SUCCESS;
4285 len = l2cap_parse_conf_rsp(chan, rsp->data, len,
4286 req, sizeof(req), &result);
4287 if (len < 0) {
4288 l2cap_send_disconn_req(chan, ECONNRESET);
4289 goto done;
4290 }
4291
4292 l2cap_send_cmd(conn, l2cap_get_ident(conn),
4293 L2CAP_CONF_REQ, len, req);
4294 chan->num_conf_req++;
4295 if (result != L2CAP_CONF_SUCCESS)
4296 goto done;
4297 break;
4298 }
4299 /* fall through */
4300
4301 default:
4302 l2cap_chan_set_err(chan, ECONNRESET);
4303
4304 __set_chan_timer(chan, L2CAP_DISC_REJ_TIMEOUT);
4305 l2cap_send_disconn_req(chan, ECONNRESET);
4306 goto done;
4307 }
4308
4309 if (flags & L2CAP_CONF_FLAG_CONTINUATION)
4310 goto done;
4311
4312 set_bit(CONF_INPUT_DONE, &chan->conf_state);
4313
4314 if (test_bit(CONF_OUTPUT_DONE, &chan->conf_state)) {
4315 set_default_fcs(chan);
4316
4317 if (chan->mode == L2CAP_MODE_ERTM ||
4318 chan->mode == L2CAP_MODE_STREAMING)
4319 err = l2cap_ertm_init(chan);
4320
4321 if (err < 0)
4322 l2cap_send_disconn_req(chan, -err);
4323 else
4324 l2cap_chan_ready(chan);
4325 }
4326
4327 done:
4328 l2cap_chan_unlock(chan);
4329 return err;
4330 }
4331
4332 static inline int l2cap_disconnect_req(struct l2cap_conn *conn,
4333 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4334 u8 *data)
4335 {
4336 struct l2cap_disconn_req *req = (struct l2cap_disconn_req *) data;
4337 struct l2cap_disconn_rsp rsp;
4338 u16 dcid, scid;
4339 struct l2cap_chan *chan;
4340
4341 if (cmd_len != sizeof(*req))
4342 return -EPROTO;
4343
4344 scid = __le16_to_cpu(req->scid);
4345 dcid = __le16_to_cpu(req->dcid);
4346
4347 BT_DBG("scid 0x%4.4x dcid 0x%4.4x", scid, dcid);
4348
4349 mutex_lock(&conn->chan_lock);
4350
4351 chan = __l2cap_get_chan_by_scid(conn, dcid);
4352 if (!chan) {
4353 mutex_unlock(&conn->chan_lock);
4354 cmd_reject_invalid_cid(conn, cmd->ident, dcid, scid);
4355 return 0;
4356 }
4357
4358 l2cap_chan_lock(chan);
4359
4360 rsp.dcid = cpu_to_le16(chan->scid);
4361 rsp.scid = cpu_to_le16(chan->dcid);
4362 l2cap_send_cmd(conn, cmd->ident, L2CAP_DISCONN_RSP, sizeof(rsp), &rsp);
4363
4364 chan->ops->set_shutdown(chan);
4365
4366 l2cap_chan_hold(chan);
4367 l2cap_chan_del(chan, ECONNRESET);
4368
4369 l2cap_chan_unlock(chan);
4370
4371 chan->ops->close(chan);
4372 l2cap_chan_put(chan);
4373
4374 mutex_unlock(&conn->chan_lock);
4375
4376 return 0;
4377 }
4378
4379 static inline int l2cap_disconnect_rsp(struct l2cap_conn *conn,
4380 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4381 u8 *data)
4382 {
4383 struct l2cap_disconn_rsp *rsp = (struct l2cap_disconn_rsp *) data;
4384 u16 dcid, scid;
4385 struct l2cap_chan *chan;
4386
4387 if (cmd_len != sizeof(*rsp))
4388 return -EPROTO;
4389
4390 scid = __le16_to_cpu(rsp->scid);
4391 dcid = __le16_to_cpu(rsp->dcid);
4392
4393 BT_DBG("dcid 0x%4.4x scid 0x%4.4x", dcid, scid);
4394
4395 mutex_lock(&conn->chan_lock);
4396
4397 chan = __l2cap_get_chan_by_scid(conn, scid);
4398 if (!chan) {
4399 mutex_unlock(&conn->chan_lock);
4400 return 0;
4401 }
4402
4403 l2cap_chan_lock(chan);
4404
4405 if (chan->state != BT_DISCONN) {
4406 l2cap_chan_unlock(chan);
4407 mutex_unlock(&conn->chan_lock);
4408 return 0;
4409 }
4410
4411 l2cap_chan_hold(chan);
4412 l2cap_chan_del(chan, 0);
4413
4414 l2cap_chan_unlock(chan);
4415
4416 chan->ops->close(chan);
4417 l2cap_chan_put(chan);
4418
4419 mutex_unlock(&conn->chan_lock);
4420
4421 return 0;
4422 }
4423
4424 static inline int l2cap_information_req(struct l2cap_conn *conn,
4425 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4426 u8 *data)
4427 {
4428 struct l2cap_info_req *req = (struct l2cap_info_req *) data;
4429 u16 type;
4430
4431 if (cmd_len != sizeof(*req))
4432 return -EPROTO;
4433
4434 type = __le16_to_cpu(req->type);
4435
4436 BT_DBG("type 0x%4.4x", type);
4437
4438 if (type == L2CAP_IT_FEAT_MASK) {
4439 u8 buf[8];
4440 u32 feat_mask = l2cap_feat_mask;
4441 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) buf;
4442 rsp->type = cpu_to_le16(L2CAP_IT_FEAT_MASK);
4443 rsp->result = cpu_to_le16(L2CAP_IR_SUCCESS);
4444 if (!disable_ertm)
4445 feat_mask |= L2CAP_FEAT_ERTM | L2CAP_FEAT_STREAMING
4446 | L2CAP_FEAT_FCS;
4447 if (conn->local_fixed_chan & L2CAP_FC_A2MP)
4448 feat_mask |= L2CAP_FEAT_EXT_FLOW
4449 | L2CAP_FEAT_EXT_WINDOW;
4450
4451 put_unaligned_le32(feat_mask, rsp->data);
4452 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(buf),
4453 buf);
4454 } else if (type == L2CAP_IT_FIXED_CHAN) {
4455 u8 buf[12];
4456 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) buf;
4457
4458 rsp->type = cpu_to_le16(L2CAP_IT_FIXED_CHAN);
4459 rsp->result = cpu_to_le16(L2CAP_IR_SUCCESS);
4460 rsp->data[0] = conn->local_fixed_chan;
4461 memset(rsp->data + 1, 0, 7);
4462 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(buf),
4463 buf);
4464 } else {
4465 struct l2cap_info_rsp rsp;
4466 rsp.type = cpu_to_le16(type);
4467 rsp.result = cpu_to_le16(L2CAP_IR_NOTSUPP);
4468 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(rsp),
4469 &rsp);
4470 }
4471
4472 return 0;
4473 }
4474
4475 static inline int l2cap_information_rsp(struct l2cap_conn *conn,
4476 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4477 u8 *data)
4478 {
4479 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) data;
4480 u16 type, result;
4481
4482 if (cmd_len < sizeof(*rsp))
4483 return -EPROTO;
4484
4485 type = __le16_to_cpu(rsp->type);
4486 result = __le16_to_cpu(rsp->result);
4487
4488 BT_DBG("type 0x%4.4x result 0x%2.2x", type, result);
4489
4490 /* L2CAP Info req/rsp are unbound to channels, add extra checks */
4491 if (cmd->ident != conn->info_ident ||
4492 conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE)
4493 return 0;
4494
4495 cancel_delayed_work(&conn->info_timer);
4496
4497 if (result != L2CAP_IR_SUCCESS) {
4498 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4499 conn->info_ident = 0;
4500
4501 l2cap_conn_start(conn);
4502
4503 return 0;
4504 }
4505
4506 switch (type) {
4507 case L2CAP_IT_FEAT_MASK:
4508 conn->feat_mask = get_unaligned_le32(rsp->data);
4509
4510 if (conn->feat_mask & L2CAP_FEAT_FIXED_CHAN) {
4511 struct l2cap_info_req req;
4512 req.type = cpu_to_le16(L2CAP_IT_FIXED_CHAN);
4513
4514 conn->info_ident = l2cap_get_ident(conn);
4515
4516 l2cap_send_cmd(conn, conn->info_ident,
4517 L2CAP_INFO_REQ, sizeof(req), &req);
4518 } else {
4519 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4520 conn->info_ident = 0;
4521
4522 l2cap_conn_start(conn);
4523 }
4524 break;
4525
4526 case L2CAP_IT_FIXED_CHAN:
4527 conn->remote_fixed_chan = rsp->data[0];
4528 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4529 conn->info_ident = 0;
4530
4531 l2cap_conn_start(conn);
4532 break;
4533 }
4534
4535 return 0;
4536 }
4537
4538 static int l2cap_create_channel_req(struct l2cap_conn *conn,
4539 struct l2cap_cmd_hdr *cmd,
4540 u16 cmd_len, void *data)
4541 {
4542 struct l2cap_create_chan_req *req = data;
4543 struct l2cap_create_chan_rsp rsp;
4544 struct l2cap_chan *chan;
4545 struct hci_dev *hdev;
4546 u16 psm, scid;
4547
4548 if (cmd_len != sizeof(*req))
4549 return -EPROTO;
4550
4551 if (!(conn->local_fixed_chan & L2CAP_FC_A2MP))
4552 return -EINVAL;
4553
4554 psm = le16_to_cpu(req->psm);
4555 scid = le16_to_cpu(req->scid);
4556
4557 BT_DBG("psm 0x%2.2x, scid 0x%4.4x, amp_id %d", psm, scid, req->amp_id);
4558
4559 /* For controller id 0 make BR/EDR connection */
4560 if (req->amp_id == AMP_ID_BREDR) {
4561 l2cap_connect(conn, cmd, data, L2CAP_CREATE_CHAN_RSP,
4562 req->amp_id);
4563 return 0;
4564 }
4565
4566 /* Validate AMP controller id */
4567 hdev = hci_dev_get(req->amp_id);
4568 if (!hdev)
4569 goto error;
4570
4571 if (hdev->dev_type != HCI_AMP || !test_bit(HCI_UP, &hdev->flags)) {
4572 hci_dev_put(hdev);
4573 goto error;
4574 }
4575
4576 chan = l2cap_connect(conn, cmd, data, L2CAP_CREATE_CHAN_RSP,
4577 req->amp_id);
4578 if (chan) {
4579 struct amp_mgr *mgr = conn->hcon->amp_mgr;
4580 struct hci_conn *hs_hcon;
4581
4582 hs_hcon = hci_conn_hash_lookup_ba(hdev, AMP_LINK,
4583 &conn->hcon->dst);
4584 if (!hs_hcon) {
4585 hci_dev_put(hdev);
4586 cmd_reject_invalid_cid(conn, cmd->ident, chan->scid,
4587 chan->dcid);
4588 return 0;
4589 }
4590
4591 BT_DBG("mgr %p bredr_chan %p hs_hcon %p", mgr, chan, hs_hcon);
4592
4593 mgr->bredr_chan = chan;
4594 chan->hs_hcon = hs_hcon;
4595 chan->fcs = L2CAP_FCS_NONE;
4596 conn->mtu = hdev->block_mtu;
4597 }
4598
4599 hci_dev_put(hdev);
4600
4601 return 0;
4602
4603 error:
4604 rsp.dcid = 0;
4605 rsp.scid = cpu_to_le16(scid);
4606 rsp.result = cpu_to_le16(L2CAP_CR_BAD_AMP);
4607 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
4608
4609 l2cap_send_cmd(conn, cmd->ident, L2CAP_CREATE_CHAN_RSP,
4610 sizeof(rsp), &rsp);
4611
4612 return 0;
4613 }
4614
4615 static void l2cap_send_move_chan_req(struct l2cap_chan *chan, u8 dest_amp_id)
4616 {
4617 struct l2cap_move_chan_req req;
4618 u8 ident;
4619
4620 BT_DBG("chan %p, dest_amp_id %d", chan, dest_amp_id);
4621
4622 ident = l2cap_get_ident(chan->conn);
4623 chan->ident = ident;
4624
4625 req.icid = cpu_to_le16(chan->scid);
4626 req.dest_amp_id = dest_amp_id;
4627
4628 l2cap_send_cmd(chan->conn, ident, L2CAP_MOVE_CHAN_REQ, sizeof(req),
4629 &req);
4630
4631 __set_chan_timer(chan, L2CAP_MOVE_TIMEOUT);
4632 }
4633
4634 static void l2cap_send_move_chan_rsp(struct l2cap_chan *chan, u16 result)
4635 {
4636 struct l2cap_move_chan_rsp rsp;
4637
4638 BT_DBG("chan %p, result 0x%4.4x", chan, result);
4639
4640 rsp.icid = cpu_to_le16(chan->dcid);
4641 rsp.result = cpu_to_le16(result);
4642
4643 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_MOVE_CHAN_RSP,
4644 sizeof(rsp), &rsp);
4645 }
4646
4647 static void l2cap_send_move_chan_cfm(struct l2cap_chan *chan, u16 result)
4648 {
4649 struct l2cap_move_chan_cfm cfm;
4650
4651 BT_DBG("chan %p, result 0x%4.4x", chan, result);
4652
4653 chan->ident = l2cap_get_ident(chan->conn);
4654
4655 cfm.icid = cpu_to_le16(chan->scid);
4656 cfm.result = cpu_to_le16(result);
4657
4658 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_MOVE_CHAN_CFM,
4659 sizeof(cfm), &cfm);
4660
4661 __set_chan_timer(chan, L2CAP_MOVE_TIMEOUT);
4662 }
4663
4664 static void l2cap_send_move_chan_cfm_icid(struct l2cap_conn *conn, u16 icid)
4665 {
4666 struct l2cap_move_chan_cfm cfm;
4667
4668 BT_DBG("conn %p, icid 0x%4.4x", conn, icid);
4669
4670 cfm.icid = cpu_to_le16(icid);
4671 cfm.result = cpu_to_le16(L2CAP_MC_UNCONFIRMED);
4672
4673 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_MOVE_CHAN_CFM,
4674 sizeof(cfm), &cfm);
4675 }
4676
4677 static void l2cap_send_move_chan_cfm_rsp(struct l2cap_conn *conn, u8 ident,
4678 u16 icid)
4679 {
4680 struct l2cap_move_chan_cfm_rsp rsp;
4681
4682 BT_DBG("icid 0x%4.4x", icid);
4683
4684 rsp.icid = cpu_to_le16(icid);
4685 l2cap_send_cmd(conn, ident, L2CAP_MOVE_CHAN_CFM_RSP, sizeof(rsp), &rsp);
4686 }
4687
4688 static void __release_logical_link(struct l2cap_chan *chan)
4689 {
4690 chan->hs_hchan = NULL;
4691 chan->hs_hcon = NULL;
4692
4693 /* Placeholder - release the logical link */
4694 }
4695
4696 static void l2cap_logical_fail(struct l2cap_chan *chan)
4697 {
4698 /* Logical link setup failed */
4699 if (chan->state != BT_CONNECTED) {
4700 /* Create channel failure, disconnect */
4701 l2cap_send_disconn_req(chan, ECONNRESET);
4702 return;
4703 }
4704
4705 switch (chan->move_role) {
4706 case L2CAP_MOVE_ROLE_RESPONDER:
4707 l2cap_move_done(chan);
4708 l2cap_send_move_chan_rsp(chan, L2CAP_MR_NOT_SUPP);
4709 break;
4710 case L2CAP_MOVE_ROLE_INITIATOR:
4711 if (chan->move_state == L2CAP_MOVE_WAIT_LOGICAL_COMP ||
4712 chan->move_state == L2CAP_MOVE_WAIT_LOGICAL_CFM) {
4713 /* Remote has only sent pending or
4714 * success responses, clean up
4715 */
4716 l2cap_move_done(chan);
4717 }
4718
4719 /* Other amp move states imply that the move
4720 * has already aborted
4721 */
4722 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
4723 break;
4724 }
4725 }
4726
4727 static void l2cap_logical_finish_create(struct l2cap_chan *chan,
4728 struct hci_chan *hchan)
4729 {
4730 struct l2cap_conf_rsp rsp;
4731
4732 chan->hs_hchan = hchan;
4733 chan->hs_hcon->l2cap_data = chan->conn;
4734
4735 l2cap_send_efs_conf_rsp(chan, &rsp, chan->ident, 0);
4736
4737 if (test_bit(CONF_INPUT_DONE, &chan->conf_state)) {
4738 int err;
4739
4740 set_default_fcs(chan);
4741
4742 err = l2cap_ertm_init(chan);
4743 if (err < 0)
4744 l2cap_send_disconn_req(chan, -err);
4745 else
4746 l2cap_chan_ready(chan);
4747 }
4748 }
4749
4750 static void l2cap_logical_finish_move(struct l2cap_chan *chan,
4751 struct hci_chan *hchan)
4752 {
4753 chan->hs_hcon = hchan->conn;
4754 chan->hs_hcon->l2cap_data = chan->conn;
4755
4756 BT_DBG("move_state %d", chan->move_state);
4757
4758 switch (chan->move_state) {
4759 case L2CAP_MOVE_WAIT_LOGICAL_COMP:
4760 /* Move confirm will be sent after a success
4761 * response is received
4762 */
4763 chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
4764 break;
4765 case L2CAP_MOVE_WAIT_LOGICAL_CFM:
4766 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
4767 chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
4768 } else if (chan->move_role == L2CAP_MOVE_ROLE_INITIATOR) {
4769 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM_RSP;
4770 l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
4771 } else if (chan->move_role == L2CAP_MOVE_ROLE_RESPONDER) {
4772 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
4773 l2cap_send_move_chan_rsp(chan, L2CAP_MR_SUCCESS);
4774 }
4775 break;
4776 default:
4777 /* Move was not in expected state, free the channel */
4778 __release_logical_link(chan);
4779
4780 chan->move_state = L2CAP_MOVE_STABLE;
4781 }
4782 }
4783
4784 /* Call with chan locked */
4785 void l2cap_logical_cfm(struct l2cap_chan *chan, struct hci_chan *hchan,
4786 u8 status)
4787 {
4788 BT_DBG("chan %p, hchan %p, status %d", chan, hchan, status);
4789
4790 if (status) {
4791 l2cap_logical_fail(chan);
4792 __release_logical_link(chan);
4793 return;
4794 }
4795
4796 if (chan->state != BT_CONNECTED) {
4797 /* Ignore logical link if channel is on BR/EDR */
4798 if (chan->local_amp_id != AMP_ID_BREDR)
4799 l2cap_logical_finish_create(chan, hchan);
4800 } else {
4801 l2cap_logical_finish_move(chan, hchan);
4802 }
4803 }
4804
4805 void l2cap_move_start(struct l2cap_chan *chan)
4806 {
4807 BT_DBG("chan %p", chan);
4808
4809 if (chan->local_amp_id == AMP_ID_BREDR) {
4810 if (chan->chan_policy != BT_CHANNEL_POLICY_AMP_PREFERRED)
4811 return;
4812 chan->move_role = L2CAP_MOVE_ROLE_INITIATOR;
4813 chan->move_state = L2CAP_MOVE_WAIT_PREPARE;
4814 /* Placeholder - start physical link setup */
4815 } else {
4816 chan->move_role = L2CAP_MOVE_ROLE_INITIATOR;
4817 chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
4818 chan->move_id = 0;
4819 l2cap_move_setup(chan);
4820 l2cap_send_move_chan_req(chan, 0);
4821 }
4822 }
4823
4824 static void l2cap_do_create(struct l2cap_chan *chan, int result,
4825 u8 local_amp_id, u8 remote_amp_id)
4826 {
4827 BT_DBG("chan %p state %s %u -> %u", chan, state_to_string(chan->state),
4828 local_amp_id, remote_amp_id);
4829
4830 chan->fcs = L2CAP_FCS_NONE;
4831
4832 /* Outgoing channel on AMP */
4833 if (chan->state == BT_CONNECT) {
4834 if (result == L2CAP_CR_SUCCESS) {
4835 chan->local_amp_id = local_amp_id;
4836 l2cap_send_create_chan_req(chan, remote_amp_id);
4837 } else {
4838 /* Revert to BR/EDR connect */
4839 l2cap_send_conn_req(chan);
4840 }
4841
4842 return;
4843 }
4844
4845 /* Incoming channel on AMP */
4846 if (__l2cap_no_conn_pending(chan)) {
4847 struct l2cap_conn_rsp rsp;
4848 char buf[128];
4849 rsp.scid = cpu_to_le16(chan->dcid);
4850 rsp.dcid = cpu_to_le16(chan->scid);
4851
4852 if (result == L2CAP_CR_SUCCESS) {
4853 /* Send successful response */
4854 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
4855 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
4856 } else {
4857 /* Send negative response */
4858 rsp.result = cpu_to_le16(L2CAP_CR_NO_MEM);
4859 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
4860 }
4861
4862 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_CREATE_CHAN_RSP,
4863 sizeof(rsp), &rsp);
4864
4865 if (result == L2CAP_CR_SUCCESS) {
4866 l2cap_state_change(chan, BT_CONFIG);
4867 set_bit(CONF_REQ_SENT, &chan->conf_state);
4868 l2cap_send_cmd(chan->conn, l2cap_get_ident(chan->conn),
4869 L2CAP_CONF_REQ,
4870 l2cap_build_conf_req(chan, buf, sizeof(buf)), buf);
4871 chan->num_conf_req++;
4872 }
4873 }
4874 }
4875
4876 static void l2cap_do_move_initiate(struct l2cap_chan *chan, u8 local_amp_id,
4877 u8 remote_amp_id)
4878 {
4879 l2cap_move_setup(chan);
4880 chan->move_id = local_amp_id;
4881 chan->move_state = L2CAP_MOVE_WAIT_RSP;
4882
4883 l2cap_send_move_chan_req(chan, remote_amp_id);
4884 }
4885
4886 static void l2cap_do_move_respond(struct l2cap_chan *chan, int result)
4887 {
4888 struct hci_chan *hchan = NULL;
4889
4890 /* Placeholder - get hci_chan for logical link */
4891
4892 if (hchan) {
4893 if (hchan->state == BT_CONNECTED) {
4894 /* Logical link is ready to go */
4895 chan->hs_hcon = hchan->conn;
4896 chan->hs_hcon->l2cap_data = chan->conn;
4897 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
4898 l2cap_send_move_chan_rsp(chan, L2CAP_MR_SUCCESS);
4899
4900 l2cap_logical_cfm(chan, hchan, L2CAP_MR_SUCCESS);
4901 } else {
4902 /* Wait for logical link to be ready */
4903 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
4904 }
4905 } else {
4906 /* Logical link not available */
4907 l2cap_send_move_chan_rsp(chan, L2CAP_MR_NOT_ALLOWED);
4908 }
4909 }
4910
4911 static void l2cap_do_move_cancel(struct l2cap_chan *chan, int result)
4912 {
4913 if (chan->move_role == L2CAP_MOVE_ROLE_RESPONDER) {
4914 u8 rsp_result;
4915 if (result == -EINVAL)
4916 rsp_result = L2CAP_MR_BAD_ID;
4917 else
4918 rsp_result = L2CAP_MR_NOT_ALLOWED;
4919
4920 l2cap_send_move_chan_rsp(chan, rsp_result);
4921 }
4922
4923 chan->move_role = L2CAP_MOVE_ROLE_NONE;
4924 chan->move_state = L2CAP_MOVE_STABLE;
4925
4926 /* Restart data transmission */
4927 l2cap_ertm_send(chan);
4928 }
4929
4930 /* Invoke with locked chan */
4931 void __l2cap_physical_cfm(struct l2cap_chan *chan, int result)
4932 {
4933 u8 local_amp_id = chan->local_amp_id;
4934 u8 remote_amp_id = chan->remote_amp_id;
4935
4936 BT_DBG("chan %p, result %d, local_amp_id %d, remote_amp_id %d",
4937 chan, result, local_amp_id, remote_amp_id);
4938
4939 if (chan->state == BT_DISCONN || chan->state == BT_CLOSED)
4940 return;
4941
4942 if (chan->state != BT_CONNECTED) {
4943 l2cap_do_create(chan, result, local_amp_id, remote_amp_id);
4944 } else if (result != L2CAP_MR_SUCCESS) {
4945 l2cap_do_move_cancel(chan, result);
4946 } else {
4947 switch (chan->move_role) {
4948 case L2CAP_MOVE_ROLE_INITIATOR:
4949 l2cap_do_move_initiate(chan, local_amp_id,
4950 remote_amp_id);
4951 break;
4952 case L2CAP_MOVE_ROLE_RESPONDER:
4953 l2cap_do_move_respond(chan, result);
4954 break;
4955 default:
4956 l2cap_do_move_cancel(chan, result);
4957 break;
4958 }
4959 }
4960 }
4961
4962 static inline int l2cap_move_channel_req(struct l2cap_conn *conn,
4963 struct l2cap_cmd_hdr *cmd,
4964 u16 cmd_len, void *data)
4965 {
4966 struct l2cap_move_chan_req *req = data;
4967 struct l2cap_move_chan_rsp rsp;
4968 struct l2cap_chan *chan;
4969 u16 icid = 0;
4970 u16 result = L2CAP_MR_NOT_ALLOWED;
4971
4972 if (cmd_len != sizeof(*req))
4973 return -EPROTO;
4974
4975 icid = le16_to_cpu(req->icid);
4976
4977 BT_DBG("icid 0x%4.4x, dest_amp_id %d", icid, req->dest_amp_id);
4978
4979 if (!(conn->local_fixed_chan & L2CAP_FC_A2MP))
4980 return -EINVAL;
4981
4982 chan = l2cap_get_chan_by_dcid(conn, icid);
4983 if (!chan) {
4984 rsp.icid = cpu_to_le16(icid);
4985 rsp.result = cpu_to_le16(L2CAP_MR_NOT_ALLOWED);
4986 l2cap_send_cmd(conn, cmd->ident, L2CAP_MOVE_CHAN_RSP,
4987 sizeof(rsp), &rsp);
4988 return 0;
4989 }
4990
4991 chan->ident = cmd->ident;
4992
4993 if (chan->scid < L2CAP_CID_DYN_START ||
4994 chan->chan_policy == BT_CHANNEL_POLICY_BREDR_ONLY ||
4995 (chan->mode != L2CAP_MODE_ERTM &&
4996 chan->mode != L2CAP_MODE_STREAMING)) {
4997 result = L2CAP_MR_NOT_ALLOWED;
4998 goto send_move_response;
4999 }
5000
5001 if (chan->local_amp_id == req->dest_amp_id) {
5002 result = L2CAP_MR_SAME_ID;
5003 goto send_move_response;
5004 }
5005
5006 if (req->dest_amp_id != AMP_ID_BREDR) {
5007 struct hci_dev *hdev;
5008 hdev = hci_dev_get(req->dest_amp_id);
5009 if (!hdev || hdev->dev_type != HCI_AMP ||
5010 !test_bit(HCI_UP, &hdev->flags)) {
5011 if (hdev)
5012 hci_dev_put(hdev);
5013
5014 result = L2CAP_MR_BAD_ID;
5015 goto send_move_response;
5016 }
5017 hci_dev_put(hdev);
5018 }
5019
5020 /* Detect a move collision. Only send a collision response
5021 * if this side has "lost", otherwise proceed with the move.
5022 * The winner has the larger bd_addr.
5023 */
5024 if ((__chan_is_moving(chan) ||
5025 chan->move_role != L2CAP_MOVE_ROLE_NONE) &&
5026 bacmp(&conn->hcon->src, &conn->hcon->dst) > 0) {
5027 result = L2CAP_MR_COLLISION;
5028 goto send_move_response;
5029 }
5030
5031 chan->move_role = L2CAP_MOVE_ROLE_RESPONDER;
5032 l2cap_move_setup(chan);
5033 chan->move_id = req->dest_amp_id;
5034 icid = chan->dcid;
5035
5036 if (req->dest_amp_id == AMP_ID_BREDR) {
5037 /* Moving to BR/EDR */
5038 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
5039 chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
5040 result = L2CAP_MR_PEND;
5041 } else {
5042 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
5043 result = L2CAP_MR_SUCCESS;
5044 }
5045 } else {
5046 chan->move_state = L2CAP_MOVE_WAIT_PREPARE;
5047 /* Placeholder - uncomment when amp functions are available */
5048 /*amp_accept_physical(chan, req->dest_amp_id);*/
5049 result = L2CAP_MR_PEND;
5050 }
5051
5052 send_move_response:
5053 l2cap_send_move_chan_rsp(chan, result);
5054
5055 l2cap_chan_unlock(chan);
5056
5057 return 0;
5058 }
5059
5060 static void l2cap_move_continue(struct l2cap_conn *conn, u16 icid, u16 result)
5061 {
5062 struct l2cap_chan *chan;
5063 struct hci_chan *hchan = NULL;
5064
5065 chan = l2cap_get_chan_by_scid(conn, icid);
5066 if (!chan) {
5067 l2cap_send_move_chan_cfm_icid(conn, icid);
5068 return;
5069 }
5070
5071 __clear_chan_timer(chan);
5072 if (result == L2CAP_MR_PEND)
5073 __set_chan_timer(chan, L2CAP_MOVE_ERTX_TIMEOUT);
5074
5075 switch (chan->move_state) {
5076 case L2CAP_MOVE_WAIT_LOGICAL_COMP:
5077 /* Move confirm will be sent when logical link
5078 * is complete.
5079 */
5080 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
5081 break;
5082 case L2CAP_MOVE_WAIT_RSP_SUCCESS:
5083 if (result == L2CAP_MR_PEND) {
5084 break;
5085 } else if (test_bit(CONN_LOCAL_BUSY,
5086 &chan->conn_state)) {
5087 chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
5088 } else {
5089 /* Logical link is up or moving to BR/EDR,
5090 * proceed with move
5091 */
5092 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM_RSP;
5093 l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
5094 }
5095 break;
5096 case L2CAP_MOVE_WAIT_RSP:
5097 /* Moving to AMP */
5098 if (result == L2CAP_MR_SUCCESS) {
5099 /* Remote is ready, send confirm immediately
5100 * after logical link is ready
5101 */
5102 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
5103 } else {
5104 /* Both logical link and move success
5105 * are required to confirm
5106 */
5107 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_COMP;
5108 }
5109
5110 /* Placeholder - get hci_chan for logical link */
5111 if (!hchan) {
5112 /* Logical link not available */
5113 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5114 break;
5115 }
5116
5117 /* If the logical link is not yet connected, do not
5118 * send confirmation.
5119 */
5120 if (hchan->state != BT_CONNECTED)
5121 break;
5122
5123 /* Logical link is already ready to go */
5124
5125 chan->hs_hcon = hchan->conn;
5126 chan->hs_hcon->l2cap_data = chan->conn;
5127
5128 if (result == L2CAP_MR_SUCCESS) {
5129 /* Can confirm now */
5130 l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
5131 } else {
5132 /* Now only need move success
5133 * to confirm
5134 */
5135 chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
5136 }
5137
5138 l2cap_logical_cfm(chan, hchan, L2CAP_MR_SUCCESS);
5139 break;
5140 default:
5141 /* Any other amp move state means the move failed. */
5142 chan->move_id = chan->local_amp_id;
5143 l2cap_move_done(chan);
5144 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5145 }
5146
5147 l2cap_chan_unlock(chan);
5148 }
5149
5150 static void l2cap_move_fail(struct l2cap_conn *conn, u8 ident, u16 icid,
5151 u16 result)
5152 {
5153 struct l2cap_chan *chan;
5154
5155 chan = l2cap_get_chan_by_ident(conn, ident);
5156 if (!chan) {
5157 /* Could not locate channel, icid is best guess */
5158 l2cap_send_move_chan_cfm_icid(conn, icid);
5159 return;
5160 }
5161
5162 __clear_chan_timer(chan);
5163
5164 if (chan->move_role == L2CAP_MOVE_ROLE_INITIATOR) {
5165 if (result == L2CAP_MR_COLLISION) {
5166 chan->move_role = L2CAP_MOVE_ROLE_RESPONDER;
5167 } else {
5168 /* Cleanup - cancel move */
5169 chan->move_id = chan->local_amp_id;
5170 l2cap_move_done(chan);
5171 }
5172 }
5173
5174 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5175
5176 l2cap_chan_unlock(chan);
5177 }
5178
5179 static int l2cap_move_channel_rsp(struct l2cap_conn *conn,
5180 struct l2cap_cmd_hdr *cmd,
5181 u16 cmd_len, void *data)
5182 {
5183 struct l2cap_move_chan_rsp *rsp = data;
5184 u16 icid, result;
5185
5186 if (cmd_len != sizeof(*rsp))
5187 return -EPROTO;
5188
5189 icid = le16_to_cpu(rsp->icid);
5190 result = le16_to_cpu(rsp->result);
5191
5192 BT_DBG("icid 0x%4.4x, result 0x%4.4x", icid, result);
5193
5194 if (result == L2CAP_MR_SUCCESS || result == L2CAP_MR_PEND)
5195 l2cap_move_continue(conn, icid, result);
5196 else
5197 l2cap_move_fail(conn, cmd->ident, icid, result);
5198
5199 return 0;
5200 }
5201
5202 static int l2cap_move_channel_confirm(struct l2cap_conn *conn,
5203 struct l2cap_cmd_hdr *cmd,
5204 u16 cmd_len, void *data)
5205 {
5206 struct l2cap_move_chan_cfm *cfm = data;
5207 struct l2cap_chan *chan;
5208 u16 icid, result;
5209
5210 if (cmd_len != sizeof(*cfm))
5211 return -EPROTO;
5212
5213 icid = le16_to_cpu(cfm->icid);
5214 result = le16_to_cpu(cfm->result);
5215
5216 BT_DBG("icid 0x%4.4x, result 0x%4.4x", icid, result);
5217
5218 chan = l2cap_get_chan_by_dcid(conn, icid);
5219 if (!chan) {
5220 /* Spec requires a response even if the icid was not found */
5221 l2cap_send_move_chan_cfm_rsp(conn, cmd->ident, icid);
5222 return 0;
5223 }
5224
5225 if (chan->move_state == L2CAP_MOVE_WAIT_CONFIRM) {
5226 if (result == L2CAP_MC_CONFIRMED) {
5227 chan->local_amp_id = chan->move_id;
5228 if (chan->local_amp_id == AMP_ID_BREDR)
5229 __release_logical_link(chan);
5230 } else {
5231 chan->move_id = chan->local_amp_id;
5232 }
5233
5234 l2cap_move_done(chan);
5235 }
5236
5237 l2cap_send_move_chan_cfm_rsp(conn, cmd->ident, icid);
5238
5239 l2cap_chan_unlock(chan);
5240
5241 return 0;
5242 }
5243
5244 static inline int l2cap_move_channel_confirm_rsp(struct l2cap_conn *conn,
5245 struct l2cap_cmd_hdr *cmd,
5246 u16 cmd_len, void *data)
5247 {
5248 struct l2cap_move_chan_cfm_rsp *rsp = data;
5249 struct l2cap_chan *chan;
5250 u16 icid;
5251
5252 if (cmd_len != sizeof(*rsp))
5253 return -EPROTO;
5254
5255 icid = le16_to_cpu(rsp->icid);
5256
5257 BT_DBG("icid 0x%4.4x", icid);
5258
5259 chan = l2cap_get_chan_by_scid(conn, icid);
5260 if (!chan)
5261 return 0;
5262
5263 __clear_chan_timer(chan);
5264
5265 if (chan->move_state == L2CAP_MOVE_WAIT_CONFIRM_RSP) {
5266 chan->local_amp_id = chan->move_id;
5267
5268 if (chan->local_amp_id == AMP_ID_BREDR && chan->hs_hchan)
5269 __release_logical_link(chan);
5270
5271 l2cap_move_done(chan);
5272 }
5273
5274 l2cap_chan_unlock(chan);
5275
5276 return 0;
5277 }
5278
5279 static inline int l2cap_conn_param_update_req(struct l2cap_conn *conn,
5280 struct l2cap_cmd_hdr *cmd,
5281 u16 cmd_len, u8 *data)
5282 {
5283 struct hci_conn *hcon = conn->hcon;
5284 struct l2cap_conn_param_update_req *req;
5285 struct l2cap_conn_param_update_rsp rsp;
5286 u16 min, max, latency, to_multiplier;
5287 int err;
5288
5289 if (hcon->role != HCI_ROLE_MASTER)
5290 return -EINVAL;
5291
5292 if (cmd_len != sizeof(struct l2cap_conn_param_update_req))
5293 return -EPROTO;
5294
5295 req = (struct l2cap_conn_param_update_req *) data;
5296 min = __le16_to_cpu(req->min);
5297 max = __le16_to_cpu(req->max);
5298 latency = __le16_to_cpu(req->latency);
5299 to_multiplier = __le16_to_cpu(req->to_multiplier);
5300
5301 BT_DBG("min 0x%4.4x max 0x%4.4x latency: 0x%4.4x Timeout: 0x%4.4x",
5302 min, max, latency, to_multiplier);
5303
5304 memset(&rsp, 0, sizeof(rsp));
5305
5306 err = hci_check_conn_params(min, max, latency, to_multiplier);
5307 if (err)
5308 rsp.result = cpu_to_le16(L2CAP_CONN_PARAM_REJECTED);
5309 else
5310 rsp.result = cpu_to_le16(L2CAP_CONN_PARAM_ACCEPTED);
5311
5312 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONN_PARAM_UPDATE_RSP,
5313 sizeof(rsp), &rsp);
5314
5315 if (!err) {
5316 u8 store_hint;
5317
5318 store_hint = hci_le_conn_update(hcon, min, max, latency,
5319 to_multiplier);
5320 mgmt_new_conn_param(hcon->hdev, &hcon->dst, hcon->dst_type,
5321 store_hint, min, max, latency,
5322 to_multiplier);
5323
5324 }
5325
5326 return 0;
5327 }
5328
5329 static int l2cap_le_connect_rsp(struct l2cap_conn *conn,
5330 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5331 u8 *data)
5332 {
5333 struct l2cap_le_conn_rsp *rsp = (struct l2cap_le_conn_rsp *) data;
5334 struct hci_conn *hcon = conn->hcon;
5335 u16 dcid, mtu, mps, credits, result;
5336 struct l2cap_chan *chan;
5337 int err, sec_level;
5338
5339 if (cmd_len < sizeof(*rsp))
5340 return -EPROTO;
5341
5342 dcid = __le16_to_cpu(rsp->dcid);
5343 mtu = __le16_to_cpu(rsp->mtu);
5344 mps = __le16_to_cpu(rsp->mps);
5345 credits = __le16_to_cpu(rsp->credits);
5346 result = __le16_to_cpu(rsp->result);
5347
5348 if (result == L2CAP_CR_LE_SUCCESS && (mtu < 23 || mps < 23 ||
5349 dcid < L2CAP_CID_DYN_START ||
5350 dcid > L2CAP_CID_LE_DYN_END))
5351 return -EPROTO;
5352
5353 BT_DBG("dcid 0x%4.4x mtu %u mps %u credits %u result 0x%2.2x",
5354 dcid, mtu, mps, credits, result);
5355
5356 mutex_lock(&conn->chan_lock);
5357
5358 chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
5359 if (!chan) {
5360 err = -EBADSLT;
5361 goto unlock;
5362 }
5363
5364 err = 0;
5365
5366 l2cap_chan_lock(chan);
5367
5368 switch (result) {
5369 case L2CAP_CR_LE_SUCCESS:
5370 if (__l2cap_get_chan_by_dcid(conn, dcid)) {
5371 err = -EBADSLT;
5372 break;
5373 }
5374
5375 chan->ident = 0;
5376 chan->dcid = dcid;
5377 chan->omtu = mtu;
5378 chan->remote_mps = mps;
5379 chan->tx_credits = credits;
5380 l2cap_chan_ready(chan);
5381 break;
5382
5383 case L2CAP_CR_LE_AUTHENTICATION:
5384 case L2CAP_CR_LE_ENCRYPTION:
5385 /* If we already have MITM protection we can't do
5386 * anything.
5387 */
5388 if (hcon->sec_level > BT_SECURITY_MEDIUM) {
5389 l2cap_chan_del(chan, ECONNREFUSED);
5390 break;
5391 }
5392
5393 sec_level = hcon->sec_level + 1;
5394 if (chan->sec_level < sec_level)
5395 chan->sec_level = sec_level;
5396
5397 /* We'll need to send a new Connect Request */
5398 clear_bit(FLAG_LE_CONN_REQ_SENT, &chan->flags);
5399
5400 smp_conn_security(hcon, chan->sec_level);
5401 break;
5402
5403 default:
5404 l2cap_chan_del(chan, ECONNREFUSED);
5405 break;
5406 }
5407
5408 l2cap_chan_unlock(chan);
5409
5410 unlock:
5411 mutex_unlock(&conn->chan_lock);
5412
5413 return err;
5414 }
5415
5416 static inline int l2cap_bredr_sig_cmd(struct l2cap_conn *conn,
5417 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5418 u8 *data)
5419 {
5420 int err = 0;
5421
5422 switch (cmd->code) {
5423 case L2CAP_COMMAND_REJ:
5424 l2cap_command_rej(conn, cmd, cmd_len, data);
5425 break;
5426
5427 case L2CAP_CONN_REQ:
5428 err = l2cap_connect_req(conn, cmd, cmd_len, data);
5429 break;
5430
5431 case L2CAP_CONN_RSP:
5432 case L2CAP_CREATE_CHAN_RSP:
5433 l2cap_connect_create_rsp(conn, cmd, cmd_len, data);
5434 break;
5435
5436 case L2CAP_CONF_REQ:
5437 err = l2cap_config_req(conn, cmd, cmd_len, data);
5438 break;
5439
5440 case L2CAP_CONF_RSP:
5441 l2cap_config_rsp(conn, cmd, cmd_len, data);
5442 break;
5443
5444 case L2CAP_DISCONN_REQ:
5445 err = l2cap_disconnect_req(conn, cmd, cmd_len, data);
5446 break;
5447
5448 case L2CAP_DISCONN_RSP:
5449 l2cap_disconnect_rsp(conn, cmd, cmd_len, data);
5450 break;
5451
5452 case L2CAP_ECHO_REQ:
5453 l2cap_send_cmd(conn, cmd->ident, L2CAP_ECHO_RSP, cmd_len, data);
5454 break;
5455
5456 case L2CAP_ECHO_RSP:
5457 break;
5458
5459 case L2CAP_INFO_REQ:
5460 err = l2cap_information_req(conn, cmd, cmd_len, data);
5461 break;
5462
5463 case L2CAP_INFO_RSP:
5464 l2cap_information_rsp(conn, cmd, cmd_len, data);
5465 break;
5466
5467 case L2CAP_CREATE_CHAN_REQ:
5468 err = l2cap_create_channel_req(conn, cmd, cmd_len, data);
5469 break;
5470
5471 case L2CAP_MOVE_CHAN_REQ:
5472 err = l2cap_move_channel_req(conn, cmd, cmd_len, data);
5473 break;
5474
5475 case L2CAP_MOVE_CHAN_RSP:
5476 l2cap_move_channel_rsp(conn, cmd, cmd_len, data);
5477 break;
5478
5479 case L2CAP_MOVE_CHAN_CFM:
5480 err = l2cap_move_channel_confirm(conn, cmd, cmd_len, data);
5481 break;
5482
5483 case L2CAP_MOVE_CHAN_CFM_RSP:
5484 l2cap_move_channel_confirm_rsp(conn, cmd, cmd_len, data);
5485 break;
5486
5487 default:
5488 BT_ERR("Unknown BR/EDR signaling command 0x%2.2x", cmd->code);
5489 err = -EINVAL;
5490 break;
5491 }
5492
5493 return err;
5494 }
5495
5496 static int l2cap_le_connect_req(struct l2cap_conn *conn,
5497 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5498 u8 *data)
5499 {
5500 struct l2cap_le_conn_req *req = (struct l2cap_le_conn_req *) data;
5501 struct l2cap_le_conn_rsp rsp;
5502 struct l2cap_chan *chan, *pchan;
5503 u16 dcid, scid, credits, mtu, mps;
5504 __le16 psm;
5505 u8 result;
5506
5507 if (cmd_len != sizeof(*req))
5508 return -EPROTO;
5509
5510 scid = __le16_to_cpu(req->scid);
5511 mtu = __le16_to_cpu(req->mtu);
5512 mps = __le16_to_cpu(req->mps);
5513 psm = req->psm;
5514 dcid = 0;
5515 credits = 0;
5516
5517 if (mtu < 23 || mps < 23)
5518 return -EPROTO;
5519
5520 BT_DBG("psm 0x%2.2x scid 0x%4.4x mtu %u mps %u", __le16_to_cpu(psm),
5521 scid, mtu, mps);
5522
5523 /* Check if we have socket listening on psm */
5524 pchan = l2cap_global_chan_by_psm(BT_LISTEN, psm, &conn->hcon->src,
5525 &conn->hcon->dst, LE_LINK);
5526 if (!pchan) {
5527 result = L2CAP_CR_LE_BAD_PSM;
5528 chan = NULL;
5529 goto response;
5530 }
5531
5532 mutex_lock(&conn->chan_lock);
5533 l2cap_chan_lock(pchan);
5534
5535 if (!smp_sufficient_security(conn->hcon, pchan->sec_level,
5536 SMP_ALLOW_STK)) {
5537 result = L2CAP_CR_LE_AUTHENTICATION;
5538 chan = NULL;
5539 goto response_unlock;
5540 }
5541
5542 /* Check for valid dynamic CID range */
5543 if (scid < L2CAP_CID_DYN_START || scid > L2CAP_CID_LE_DYN_END) {
5544 result = L2CAP_CR_LE_INVALID_SCID;
5545 chan = NULL;
5546 goto response_unlock;
5547 }
5548
5549 /* Check if we already have channel with that dcid */
5550 if (__l2cap_get_chan_by_dcid(conn, scid)) {
5551 result = L2CAP_CR_LE_SCID_IN_USE;
5552 chan = NULL;
5553 goto response_unlock;
5554 }
5555
5556 chan = pchan->ops->new_connection(pchan);
5557 if (!chan) {
5558 result = L2CAP_CR_LE_NO_MEM;
5559 goto response_unlock;
5560 }
5561
5562 bacpy(&chan->src, &conn->hcon->src);
5563 bacpy(&chan->dst, &conn->hcon->dst);
5564 chan->src_type = bdaddr_src_type(conn->hcon);
5565 chan->dst_type = bdaddr_dst_type(conn->hcon);
5566 chan->psm = psm;
5567 chan->dcid = scid;
5568 chan->omtu = mtu;
5569 chan->remote_mps = mps;
5570
5571 __l2cap_chan_add(conn, chan);
5572
5573 l2cap_le_flowctl_init(chan, __le16_to_cpu(req->credits));
5574
5575 dcid = chan->scid;
5576 credits = chan->rx_credits;
5577
5578 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
5579
5580 chan->ident = cmd->ident;
5581
5582 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
5583 l2cap_state_change(chan, BT_CONNECT2);
5584 /* The following result value is actually not defined
5585 * for LE CoC but we use it to let the function know
5586 * that it should bail out after doing its cleanup
5587 * instead of sending a response.
5588 */
5589 result = L2CAP_CR_PEND;
5590 chan->ops->defer(chan);
5591 } else {
5592 l2cap_chan_ready(chan);
5593 result = L2CAP_CR_LE_SUCCESS;
5594 }
5595
5596 response_unlock:
5597 l2cap_chan_unlock(pchan);
5598 mutex_unlock(&conn->chan_lock);
5599 l2cap_chan_put(pchan);
5600
5601 if (result == L2CAP_CR_PEND)
5602 return 0;
5603
5604 response:
5605 if (chan) {
5606 rsp.mtu = cpu_to_le16(chan->imtu);
5607 rsp.mps = cpu_to_le16(chan->mps);
5608 } else {
5609 rsp.mtu = 0;
5610 rsp.mps = 0;
5611 }
5612
5613 rsp.dcid = cpu_to_le16(dcid);
5614 rsp.credits = cpu_to_le16(credits);
5615 rsp.result = cpu_to_le16(result);
5616
5617 l2cap_send_cmd(conn, cmd->ident, L2CAP_LE_CONN_RSP, sizeof(rsp), &rsp);
5618
5619 return 0;
5620 }
5621
5622 static inline int l2cap_le_credits(struct l2cap_conn *conn,
5623 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5624 u8 *data)
5625 {
5626 struct l2cap_le_credits *pkt;
5627 struct l2cap_chan *chan;
5628 u16 cid, credits, max_credits;
5629
5630 if (cmd_len != sizeof(*pkt))
5631 return -EPROTO;
5632
5633 pkt = (struct l2cap_le_credits *) data;
5634 cid = __le16_to_cpu(pkt->cid);
5635 credits = __le16_to_cpu(pkt->credits);
5636
5637 BT_DBG("cid 0x%4.4x credits 0x%4.4x", cid, credits);
5638
5639 chan = l2cap_get_chan_by_dcid(conn, cid);
5640 if (!chan)
5641 return -EBADSLT;
5642
5643 max_credits = LE_FLOWCTL_MAX_CREDITS - chan->tx_credits;
5644 if (credits > max_credits) {
5645 BT_ERR("LE credits overflow");
5646 l2cap_send_disconn_req(chan, ECONNRESET);
5647 l2cap_chan_unlock(chan);
5648
5649 /* Return 0 so that we don't trigger an unnecessary
5650 * command reject packet.
5651 */
5652 return 0;
5653 }
5654
5655 chan->tx_credits += credits;
5656
5657 /* Resume sending */
5658 l2cap_le_flowctl_send(chan);
5659
5660 if (chan->tx_credits)
5661 chan->ops->resume(chan);
5662
5663 l2cap_chan_unlock(chan);
5664
5665 return 0;
5666 }
5667
5668 static inline int l2cap_le_command_rej(struct l2cap_conn *conn,
5669 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5670 u8 *data)
5671 {
5672 struct l2cap_cmd_rej_unk *rej = (struct l2cap_cmd_rej_unk *) data;
5673 struct l2cap_chan *chan;
5674
5675 if (cmd_len < sizeof(*rej))
5676 return -EPROTO;
5677
5678 mutex_lock(&conn->chan_lock);
5679
5680 chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
5681 if (!chan)
5682 goto done;
5683
5684 l2cap_chan_lock(chan);
5685 l2cap_chan_del(chan, ECONNREFUSED);
5686 l2cap_chan_unlock(chan);
5687
5688 done:
5689 mutex_unlock(&conn->chan_lock);
5690 return 0;
5691 }
5692
5693 static inline int l2cap_le_sig_cmd(struct l2cap_conn *conn,
5694 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5695 u8 *data)
5696 {
5697 int err = 0;
5698
5699 switch (cmd->code) {
5700 case L2CAP_COMMAND_REJ:
5701 l2cap_le_command_rej(conn, cmd, cmd_len, data);
5702 break;
5703
5704 case L2CAP_CONN_PARAM_UPDATE_REQ:
5705 err = l2cap_conn_param_update_req(conn, cmd, cmd_len, data);
5706 break;
5707
5708 case L2CAP_CONN_PARAM_UPDATE_RSP:
5709 break;
5710
5711 case L2CAP_LE_CONN_RSP:
5712 l2cap_le_connect_rsp(conn, cmd, cmd_len, data);
5713 break;
5714
5715 case L2CAP_LE_CONN_REQ:
5716 err = l2cap_le_connect_req(conn, cmd, cmd_len, data);
5717 break;
5718
5719 case L2CAP_LE_CREDITS:
5720 err = l2cap_le_credits(conn, cmd, cmd_len, data);
5721 break;
5722
5723 case L2CAP_DISCONN_REQ:
5724 err = l2cap_disconnect_req(conn, cmd, cmd_len, data);
5725 break;
5726
5727 case L2CAP_DISCONN_RSP:
5728 l2cap_disconnect_rsp(conn, cmd, cmd_len, data);
5729 break;
5730
5731 default:
5732 BT_ERR("Unknown LE signaling command 0x%2.2x", cmd->code);
5733 err = -EINVAL;
5734 break;
5735 }
5736
5737 return err;
5738 }
5739
5740 static inline void l2cap_le_sig_channel(struct l2cap_conn *conn,
5741 struct sk_buff *skb)
5742 {
5743 struct hci_conn *hcon = conn->hcon;
5744 struct l2cap_cmd_hdr *cmd;
5745 u16 len;
5746 int err;
5747
5748 if (hcon->type != LE_LINK)
5749 goto drop;
5750
5751 if (skb->len < L2CAP_CMD_HDR_SIZE)
5752 goto drop;
5753
5754 cmd = (void *) skb->data;
5755 skb_pull(skb, L2CAP_CMD_HDR_SIZE);
5756
5757 len = le16_to_cpu(cmd->len);
5758
5759 BT_DBG("code 0x%2.2x len %d id 0x%2.2x", cmd->code, len, cmd->ident);
5760
5761 if (len != skb->len || !cmd->ident) {
5762 BT_DBG("corrupted command");
5763 goto drop;
5764 }
5765
5766 err = l2cap_le_sig_cmd(conn, cmd, len, skb->data);
5767 if (err) {
5768 struct l2cap_cmd_rej_unk rej;
5769
5770 BT_ERR("Wrong link type (%d)", err);
5771
5772 rej.reason = cpu_to_le16(L2CAP_REJ_NOT_UNDERSTOOD);
5773 l2cap_send_cmd(conn, cmd->ident, L2CAP_COMMAND_REJ,
5774 sizeof(rej), &rej);
5775 }
5776
5777 drop:
5778 kfree_skb(skb);
5779 }
5780
5781 static inline void l2cap_sig_channel(struct l2cap_conn *conn,
5782 struct sk_buff *skb)
5783 {
5784 struct hci_conn *hcon = conn->hcon;
5785 u8 *data = skb->data;
5786 int len = skb->len;
5787 struct l2cap_cmd_hdr cmd;
5788 int err;
5789
5790 l2cap_raw_recv(conn, skb);
5791
5792 if (hcon->type != ACL_LINK)
5793 goto drop;
5794
5795 while (len >= L2CAP_CMD_HDR_SIZE) {
5796 u16 cmd_len;
5797 memcpy(&cmd, data, L2CAP_CMD_HDR_SIZE);
5798 data += L2CAP_CMD_HDR_SIZE;
5799 len -= L2CAP_CMD_HDR_SIZE;
5800
5801 cmd_len = le16_to_cpu(cmd.len);
5802
5803 BT_DBG("code 0x%2.2x len %d id 0x%2.2x", cmd.code, cmd_len,
5804 cmd.ident);
5805
5806 if (cmd_len > len || !cmd.ident) {
5807 BT_DBG("corrupted command");
5808 break;
5809 }
5810
5811 err = l2cap_bredr_sig_cmd(conn, &cmd, cmd_len, data);
5812 if (err) {
5813 struct l2cap_cmd_rej_unk rej;
5814
5815 BT_ERR("Wrong link type (%d)", err);
5816
5817 rej.reason = cpu_to_le16(L2CAP_REJ_NOT_UNDERSTOOD);
5818 l2cap_send_cmd(conn, cmd.ident, L2CAP_COMMAND_REJ,
5819 sizeof(rej), &rej);
5820 }
5821
5822 data += cmd_len;
5823 len -= cmd_len;
5824 }
5825
5826 drop:
5827 kfree_skb(skb);
5828 }
5829
5830 static int l2cap_check_fcs(struct l2cap_chan *chan, struct sk_buff *skb)
5831 {
5832 u16 our_fcs, rcv_fcs;
5833 int hdr_size;
5834
5835 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
5836 hdr_size = L2CAP_EXT_HDR_SIZE;
5837 else
5838 hdr_size = L2CAP_ENH_HDR_SIZE;
5839
5840 if (chan->fcs == L2CAP_FCS_CRC16) {
5841 skb_trim(skb, skb->len - L2CAP_FCS_SIZE);
5842 rcv_fcs = get_unaligned_le16(skb->data + skb->len);
5843 our_fcs = crc16(0, skb->data - hdr_size, skb->len + hdr_size);
5844
5845 if (our_fcs != rcv_fcs)
5846 return -EBADMSG;
5847 }
5848 return 0;
5849 }
5850
5851 static void l2cap_send_i_or_rr_or_rnr(struct l2cap_chan *chan)
5852 {
5853 struct l2cap_ctrl control;
5854
5855 BT_DBG("chan %p", chan);
5856
5857 memset(&control, 0, sizeof(control));
5858 control.sframe = 1;
5859 control.final = 1;
5860 control.reqseq = chan->buffer_seq;
5861 set_bit(CONN_SEND_FBIT, &chan->conn_state);
5862
5863 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
5864 control.super = L2CAP_SUPER_RNR;
5865 l2cap_send_sframe(chan, &control);
5866 }
5867
5868 if (test_and_clear_bit(CONN_REMOTE_BUSY, &chan->conn_state) &&
5869 chan->unacked_frames > 0)
5870 __set_retrans_timer(chan);
5871
5872 /* Send pending iframes */
5873 l2cap_ertm_send(chan);
5874
5875 if (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state) &&
5876 test_bit(CONN_SEND_FBIT, &chan->conn_state)) {
5877 /* F-bit wasn't sent in an s-frame or i-frame yet, so
5878 * send it now.
5879 */
5880 control.super = L2CAP_SUPER_RR;
5881 l2cap_send_sframe(chan, &control);
5882 }
5883 }
5884
5885 static void append_skb_frag(struct sk_buff *skb, struct sk_buff *new_frag,
5886 struct sk_buff **last_frag)
5887 {
5888 /* skb->len reflects data in skb as well as all fragments
5889 * skb->data_len reflects only data in fragments
5890 */
5891 if (!skb_has_frag_list(skb))
5892 skb_shinfo(skb)->frag_list = new_frag;
5893
5894 new_frag->next = NULL;
5895
5896 (*last_frag)->next = new_frag;
5897 *last_frag = new_frag;
5898
5899 skb->len += new_frag->len;
5900 skb->data_len += new_frag->len;
5901 skb->truesize += new_frag->truesize;
5902 }
5903
5904 static int l2cap_reassemble_sdu(struct l2cap_chan *chan, struct sk_buff *skb,
5905 struct l2cap_ctrl *control)
5906 {
5907 int err = -EINVAL;
5908
5909 switch (control->sar) {
5910 case L2CAP_SAR_UNSEGMENTED:
5911 if (chan->sdu)
5912 break;
5913
5914 err = chan->ops->recv(chan, skb);
5915 break;
5916
5917 case L2CAP_SAR_START:
5918 if (chan->sdu)
5919 break;
5920
5921 if (!pskb_may_pull(skb, L2CAP_SDULEN_SIZE))
5922 break;
5923
5924 chan->sdu_len = get_unaligned_le16(skb->data);
5925 skb_pull(skb, L2CAP_SDULEN_SIZE);
5926
5927 if (chan->sdu_len > chan->imtu) {
5928 err = -EMSGSIZE;
5929 break;
5930 }
5931
5932 if (skb->len >= chan->sdu_len)
5933 break;
5934
5935 chan->sdu = skb;
5936 chan->sdu_last_frag = skb;
5937
5938 skb = NULL;
5939 err = 0;
5940 break;
5941
5942 case L2CAP_SAR_CONTINUE:
5943 if (!chan->sdu)
5944 break;
5945
5946 append_skb_frag(chan->sdu, skb,
5947 &chan->sdu_last_frag);
5948 skb = NULL;
5949
5950 if (chan->sdu->len >= chan->sdu_len)
5951 break;
5952
5953 err = 0;
5954 break;
5955
5956 case L2CAP_SAR_END:
5957 if (!chan->sdu)
5958 break;
5959
5960 append_skb_frag(chan->sdu, skb,
5961 &chan->sdu_last_frag);
5962 skb = NULL;
5963
5964 if (chan->sdu->len != chan->sdu_len)
5965 break;
5966
5967 err = chan->ops->recv(chan, chan->sdu);
5968
5969 if (!err) {
5970 /* Reassembly complete */
5971 chan->sdu = NULL;
5972 chan->sdu_last_frag = NULL;
5973 chan->sdu_len = 0;
5974 }
5975 break;
5976 }
5977
5978 if (err) {
5979 kfree_skb(skb);
5980 kfree_skb(chan->sdu);
5981 chan->sdu = NULL;
5982 chan->sdu_last_frag = NULL;
5983 chan->sdu_len = 0;
5984 }
5985
5986 return err;
5987 }
5988
5989 static int l2cap_resegment(struct l2cap_chan *chan)
5990 {
5991 /* Placeholder */
5992 return 0;
5993 }
5994
5995 void l2cap_chan_busy(struct l2cap_chan *chan, int busy)
5996 {
5997 u8 event;
5998
5999 if (chan->mode != L2CAP_MODE_ERTM)
6000 return;
6001
6002 event = busy ? L2CAP_EV_LOCAL_BUSY_DETECTED : L2CAP_EV_LOCAL_BUSY_CLEAR;
6003 l2cap_tx(chan, NULL, NULL, event);
6004 }
6005
6006 static int l2cap_rx_queued_iframes(struct l2cap_chan *chan)
6007 {
6008 int err = 0;
6009 /* Pass sequential frames to l2cap_reassemble_sdu()
6010 * until a gap is encountered.
6011 */
6012
6013 BT_DBG("chan %p", chan);
6014
6015 while (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
6016 struct sk_buff *skb;
6017 BT_DBG("Searching for skb with txseq %d (queue len %d)",
6018 chan->buffer_seq, skb_queue_len(&chan->srej_q));
6019
6020 skb = l2cap_ertm_seq_in_queue(&chan->srej_q, chan->buffer_seq);
6021
6022 if (!skb)
6023 break;
6024
6025 skb_unlink(skb, &chan->srej_q);
6026 chan->buffer_seq = __next_seq(chan, chan->buffer_seq);
6027 err = l2cap_reassemble_sdu(chan, skb, &bt_cb(skb)->l2cap);
6028 if (err)
6029 break;
6030 }
6031
6032 if (skb_queue_empty(&chan->srej_q)) {
6033 chan->rx_state = L2CAP_RX_STATE_RECV;
6034 l2cap_send_ack(chan);
6035 }
6036
6037 return err;
6038 }
6039
6040 static void l2cap_handle_srej(struct l2cap_chan *chan,
6041 struct l2cap_ctrl *control)
6042 {
6043 struct sk_buff *skb;
6044
6045 BT_DBG("chan %p, control %p", chan, control);
6046
6047 if (control->reqseq == chan->next_tx_seq) {
6048 BT_DBG("Invalid reqseq %d, disconnecting", control->reqseq);
6049 l2cap_send_disconn_req(chan, ECONNRESET);
6050 return;
6051 }
6052
6053 skb = l2cap_ertm_seq_in_queue(&chan->tx_q, control->reqseq);
6054
6055 if (skb == NULL) {
6056 BT_DBG("Seq %d not available for retransmission",
6057 control->reqseq);
6058 return;
6059 }
6060
6061 if (chan->max_tx != 0 && bt_cb(skb)->l2cap.retries >= chan->max_tx) {
6062 BT_DBG("Retry limit exceeded (%d)", chan->max_tx);
6063 l2cap_send_disconn_req(chan, ECONNRESET);
6064 return;
6065 }
6066
6067 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6068
6069 if (control->poll) {
6070 l2cap_pass_to_tx(chan, control);
6071
6072 set_bit(CONN_SEND_FBIT, &chan->conn_state);
6073 l2cap_retransmit(chan, control);
6074 l2cap_ertm_send(chan);
6075
6076 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F) {
6077 set_bit(CONN_SREJ_ACT, &chan->conn_state);
6078 chan->srej_save_reqseq = control->reqseq;
6079 }
6080 } else {
6081 l2cap_pass_to_tx_fbit(chan, control);
6082
6083 if (control->final) {
6084 if (chan->srej_save_reqseq != control->reqseq ||
6085 !test_and_clear_bit(CONN_SREJ_ACT,
6086 &chan->conn_state))
6087 l2cap_retransmit(chan, control);
6088 } else {
6089 l2cap_retransmit(chan, control);
6090 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F) {
6091 set_bit(CONN_SREJ_ACT, &chan->conn_state);
6092 chan->srej_save_reqseq = control->reqseq;
6093 }
6094 }
6095 }
6096 }
6097
6098 static void l2cap_handle_rej(struct l2cap_chan *chan,
6099 struct l2cap_ctrl *control)
6100 {
6101 struct sk_buff *skb;
6102
6103 BT_DBG("chan %p, control %p", chan, control);
6104
6105 if (control->reqseq == chan->next_tx_seq) {
6106 BT_DBG("Invalid reqseq %d, disconnecting", control->reqseq);
6107 l2cap_send_disconn_req(chan, ECONNRESET);
6108 return;
6109 }
6110
6111 skb = l2cap_ertm_seq_in_queue(&chan->tx_q, control->reqseq);
6112
6113 if (chan->max_tx && skb &&
6114 bt_cb(skb)->l2cap.retries >= chan->max_tx) {
6115 BT_DBG("Retry limit exceeded (%d)", chan->max_tx);
6116 l2cap_send_disconn_req(chan, ECONNRESET);
6117 return;
6118 }
6119
6120 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6121
6122 l2cap_pass_to_tx(chan, control);
6123
6124 if (control->final) {
6125 if (!test_and_clear_bit(CONN_REJ_ACT, &chan->conn_state))
6126 l2cap_retransmit_all(chan, control);
6127 } else {
6128 l2cap_retransmit_all(chan, control);
6129 l2cap_ertm_send(chan);
6130 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F)
6131 set_bit(CONN_REJ_ACT, &chan->conn_state);
6132 }
6133 }
6134
6135 static u8 l2cap_classify_txseq(struct l2cap_chan *chan, u16 txseq)
6136 {
6137 BT_DBG("chan %p, txseq %d", chan, txseq);
6138
6139 BT_DBG("last_acked_seq %d, expected_tx_seq %d", chan->last_acked_seq,
6140 chan->expected_tx_seq);
6141
6142 if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) {
6143 if (__seq_offset(chan, txseq, chan->last_acked_seq) >=
6144 chan->tx_win) {
6145 /* See notes below regarding "double poll" and
6146 * invalid packets.
6147 */
6148 if (chan->tx_win <= ((chan->tx_win_max + 1) >> 1)) {
6149 BT_DBG("Invalid/Ignore - after SREJ");
6150 return L2CAP_TXSEQ_INVALID_IGNORE;
6151 } else {
6152 BT_DBG("Invalid - in window after SREJ sent");
6153 return L2CAP_TXSEQ_INVALID;
6154 }
6155 }
6156
6157 if (chan->srej_list.head == txseq) {
6158 BT_DBG("Expected SREJ");
6159 return L2CAP_TXSEQ_EXPECTED_SREJ;
6160 }
6161
6162 if (l2cap_ertm_seq_in_queue(&chan->srej_q, txseq)) {
6163 BT_DBG("Duplicate SREJ - txseq already stored");
6164 return L2CAP_TXSEQ_DUPLICATE_SREJ;
6165 }
6166
6167 if (l2cap_seq_list_contains(&chan->srej_list, txseq)) {
6168 BT_DBG("Unexpected SREJ - not requested");
6169 return L2CAP_TXSEQ_UNEXPECTED_SREJ;
6170 }
6171 }
6172
6173 if (chan->expected_tx_seq == txseq) {
6174 if (__seq_offset(chan, txseq, chan->last_acked_seq) >=
6175 chan->tx_win) {
6176 BT_DBG("Invalid - txseq outside tx window");
6177 return L2CAP_TXSEQ_INVALID;
6178 } else {
6179 BT_DBG("Expected");
6180 return L2CAP_TXSEQ_EXPECTED;
6181 }
6182 }
6183
6184 if (__seq_offset(chan, txseq, chan->last_acked_seq) <
6185 __seq_offset(chan, chan->expected_tx_seq, chan->last_acked_seq)) {
6186 BT_DBG("Duplicate - expected_tx_seq later than txseq");
6187 return L2CAP_TXSEQ_DUPLICATE;
6188 }
6189
6190 if (__seq_offset(chan, txseq, chan->last_acked_seq) >= chan->tx_win) {
6191 /* A source of invalid packets is a "double poll" condition,
6192 * where delays cause us to send multiple poll packets. If
6193 * the remote stack receives and processes both polls,
6194 * sequence numbers can wrap around in such a way that a
6195 * resent frame has a sequence number that looks like new data
6196 * with a sequence gap. This would trigger an erroneous SREJ
6197 * request.
6198 *
6199 * Fortunately, this is impossible with a tx window that's
6200 * less than half of the maximum sequence number, which allows
6201 * invalid frames to be safely ignored.
6202 *
6203 * With tx window sizes greater than half of the tx window
6204 * maximum, the frame is invalid and cannot be ignored. This
6205 * causes a disconnect.
6206 */
6207
6208 if (chan->tx_win <= ((chan->tx_win_max + 1) >> 1)) {
6209 BT_DBG("Invalid/Ignore - txseq outside tx window");
6210 return L2CAP_TXSEQ_INVALID_IGNORE;
6211 } else {
6212 BT_DBG("Invalid - txseq outside tx window");
6213 return L2CAP_TXSEQ_INVALID;
6214 }
6215 } else {
6216 BT_DBG("Unexpected - txseq indicates missing frames");
6217 return L2CAP_TXSEQ_UNEXPECTED;
6218 }
6219 }
6220
6221 static int l2cap_rx_state_recv(struct l2cap_chan *chan,
6222 struct l2cap_ctrl *control,
6223 struct sk_buff *skb, u8 event)
6224 {
6225 int err = 0;
6226 bool skb_in_use = false;
6227
6228 BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
6229 event);
6230
6231 switch (event) {
6232 case L2CAP_EV_RECV_IFRAME:
6233 switch (l2cap_classify_txseq(chan, control->txseq)) {
6234 case L2CAP_TXSEQ_EXPECTED:
6235 l2cap_pass_to_tx(chan, control);
6236
6237 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
6238 BT_DBG("Busy, discarding expected seq %d",
6239 control->txseq);
6240 break;
6241 }
6242
6243 chan->expected_tx_seq = __next_seq(chan,
6244 control->txseq);
6245
6246 chan->buffer_seq = chan->expected_tx_seq;
6247 skb_in_use = true;
6248
6249 err = l2cap_reassemble_sdu(chan, skb, control);
6250 if (err)
6251 break;
6252
6253 if (control->final) {
6254 if (!test_and_clear_bit(CONN_REJ_ACT,
6255 &chan->conn_state)) {
6256 control->final = 0;
6257 l2cap_retransmit_all(chan, control);
6258 l2cap_ertm_send(chan);
6259 }
6260 }
6261
6262 if (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state))
6263 l2cap_send_ack(chan);
6264 break;
6265 case L2CAP_TXSEQ_UNEXPECTED:
6266 l2cap_pass_to_tx(chan, control);
6267
6268 /* Can't issue SREJ frames in the local busy state.
6269 * Drop this frame, it will be seen as missing
6270 * when local busy is exited.
6271 */
6272 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
6273 BT_DBG("Busy, discarding unexpected seq %d",
6274 control->txseq);
6275 break;
6276 }
6277
6278 /* There was a gap in the sequence, so an SREJ
6279 * must be sent for each missing frame. The
6280 * current frame is stored for later use.
6281 */
6282 skb_queue_tail(&chan->srej_q, skb);
6283 skb_in_use = true;
6284 BT_DBG("Queued %p (queue len %d)", skb,
6285 skb_queue_len(&chan->srej_q));
6286
6287 clear_bit(CONN_SREJ_ACT, &chan->conn_state);
6288 l2cap_seq_list_clear(&chan->srej_list);
6289 l2cap_send_srej(chan, control->txseq);
6290
6291 chan->rx_state = L2CAP_RX_STATE_SREJ_SENT;
6292 break;
6293 case L2CAP_TXSEQ_DUPLICATE:
6294 l2cap_pass_to_tx(chan, control);
6295 break;
6296 case L2CAP_TXSEQ_INVALID_IGNORE:
6297 break;
6298 case L2CAP_TXSEQ_INVALID:
6299 default:
6300 l2cap_send_disconn_req(chan, ECONNRESET);
6301 break;
6302 }
6303 break;
6304 case L2CAP_EV_RECV_RR:
6305 l2cap_pass_to_tx(chan, control);
6306 if (control->final) {
6307 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6308
6309 if (!test_and_clear_bit(CONN_REJ_ACT, &chan->conn_state) &&
6310 !__chan_is_moving(chan)) {
6311 control->final = 0;
6312 l2cap_retransmit_all(chan, control);
6313 }
6314
6315 l2cap_ertm_send(chan);
6316 } else if (control->poll) {
6317 l2cap_send_i_or_rr_or_rnr(chan);
6318 } else {
6319 if (test_and_clear_bit(CONN_REMOTE_BUSY,
6320 &chan->conn_state) &&
6321 chan->unacked_frames)
6322 __set_retrans_timer(chan);
6323
6324 l2cap_ertm_send(chan);
6325 }
6326 break;
6327 case L2CAP_EV_RECV_RNR:
6328 set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6329 l2cap_pass_to_tx(chan, control);
6330 if (control && control->poll) {
6331 set_bit(CONN_SEND_FBIT, &chan->conn_state);
6332 l2cap_send_rr_or_rnr(chan, 0);
6333 }
6334 __clear_retrans_timer(chan);
6335 l2cap_seq_list_clear(&chan->retrans_list);
6336 break;
6337 case L2CAP_EV_RECV_REJ:
6338 l2cap_handle_rej(chan, control);
6339 break;
6340 case L2CAP_EV_RECV_SREJ:
6341 l2cap_handle_srej(chan, control);
6342 break;
6343 default:
6344 break;
6345 }
6346
6347 if (skb && !skb_in_use) {
6348 BT_DBG("Freeing %p", skb);
6349 kfree_skb(skb);
6350 }
6351
6352 return err;
6353 }
6354
6355 static int l2cap_rx_state_srej_sent(struct l2cap_chan *chan,
6356 struct l2cap_ctrl *control,
6357 struct sk_buff *skb, u8 event)
6358 {
6359 int err = 0;
6360 u16 txseq = control->txseq;
6361 bool skb_in_use = false;
6362
6363 BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
6364 event);
6365
6366 switch (event) {
6367 case L2CAP_EV_RECV_IFRAME:
6368 switch (l2cap_classify_txseq(chan, txseq)) {
6369 case L2CAP_TXSEQ_EXPECTED:
6370 /* Keep frame for reassembly later */
6371 l2cap_pass_to_tx(chan, control);
6372 skb_queue_tail(&chan->srej_q, skb);
6373 skb_in_use = true;
6374 BT_DBG("Queued %p (queue len %d)", skb,
6375 skb_queue_len(&chan->srej_q));
6376
6377 chan->expected_tx_seq = __next_seq(chan, txseq);
6378 break;
6379 case L2CAP_TXSEQ_EXPECTED_SREJ:
6380 l2cap_seq_list_pop(&chan->srej_list);
6381
6382 l2cap_pass_to_tx(chan, control);
6383 skb_queue_tail(&chan->srej_q, skb);
6384 skb_in_use = true;
6385 BT_DBG("Queued %p (queue len %d)", skb,
6386 skb_queue_len(&chan->srej_q));
6387
6388 err = l2cap_rx_queued_iframes(chan);
6389 if (err)
6390 break;
6391
6392 break;
6393 case L2CAP_TXSEQ_UNEXPECTED:
6394 /* Got a frame that can't be reassembled yet.
6395 * Save it for later, and send SREJs to cover
6396 * the missing frames.
6397 */
6398 skb_queue_tail(&chan->srej_q, skb);
6399 skb_in_use = true;
6400 BT_DBG("Queued %p (queue len %d)", skb,
6401 skb_queue_len(&chan->srej_q));
6402
6403 l2cap_pass_to_tx(chan, control);
6404 l2cap_send_srej(chan, control->txseq);
6405 break;
6406 case L2CAP_TXSEQ_UNEXPECTED_SREJ:
6407 /* This frame was requested with an SREJ, but
6408 * some expected retransmitted frames are
6409 * missing. Request retransmission of missing
6410 * SREJ'd frames.
6411 */
6412 skb_queue_tail(&chan->srej_q, skb);
6413 skb_in_use = true;
6414 BT_DBG("Queued %p (queue len %d)", skb,
6415 skb_queue_len(&chan->srej_q));
6416
6417 l2cap_pass_to_tx(chan, control);
6418 l2cap_send_srej_list(chan, control->txseq);
6419 break;
6420 case L2CAP_TXSEQ_DUPLICATE_SREJ:
6421 /* We've already queued this frame. Drop this copy. */
6422 l2cap_pass_to_tx(chan, control);
6423 break;
6424 case L2CAP_TXSEQ_DUPLICATE:
6425 /* Expecting a later sequence number, so this frame
6426 * was already received. Ignore it completely.
6427 */
6428 break;
6429 case L2CAP_TXSEQ_INVALID_IGNORE:
6430 break;
6431 case L2CAP_TXSEQ_INVALID:
6432 default:
6433 l2cap_send_disconn_req(chan, ECONNRESET);
6434 break;
6435 }
6436 break;
6437 case L2CAP_EV_RECV_RR:
6438 l2cap_pass_to_tx(chan, control);
6439 if (control->final) {
6440 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6441
6442 if (!test_and_clear_bit(CONN_REJ_ACT,
6443 &chan->conn_state)) {
6444 control->final = 0;
6445 l2cap_retransmit_all(chan, control);
6446 }
6447
6448 l2cap_ertm_send(chan);
6449 } else if (control->poll) {
6450 if (test_and_clear_bit(CONN_REMOTE_BUSY,
6451 &chan->conn_state) &&
6452 chan->unacked_frames) {
6453 __set_retrans_timer(chan);
6454 }
6455
6456 set_bit(CONN_SEND_FBIT, &chan->conn_state);
6457 l2cap_send_srej_tail(chan);
6458 } else {
6459 if (test_and_clear_bit(CONN_REMOTE_BUSY,
6460 &chan->conn_state) &&
6461 chan->unacked_frames)
6462 __set_retrans_timer(chan);
6463
6464 l2cap_send_ack(chan);
6465 }
6466 break;
6467 case L2CAP_EV_RECV_RNR:
6468 set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6469 l2cap_pass_to_tx(chan, control);
6470 if (control->poll) {
6471 l2cap_send_srej_tail(chan);
6472 } else {
6473 struct l2cap_ctrl rr_control;
6474 memset(&rr_control, 0, sizeof(rr_control));
6475 rr_control.sframe = 1;
6476 rr_control.super = L2CAP_SUPER_RR;
6477 rr_control.reqseq = chan->buffer_seq;
6478 l2cap_send_sframe(chan, &rr_control);
6479 }
6480
6481 break;
6482 case L2CAP_EV_RECV_REJ:
6483 l2cap_handle_rej(chan, control);
6484 break;
6485 case L2CAP_EV_RECV_SREJ:
6486 l2cap_handle_srej(chan, control);
6487 break;
6488 }
6489
6490 if (skb && !skb_in_use) {
6491 BT_DBG("Freeing %p", skb);
6492 kfree_skb(skb);
6493 }
6494
6495 return err;
6496 }
6497
6498 static int l2cap_finish_move(struct l2cap_chan *chan)
6499 {
6500 BT_DBG("chan %p", chan);
6501
6502 chan->rx_state = L2CAP_RX_STATE_RECV;
6503
6504 if (chan->hs_hcon)
6505 chan->conn->mtu = chan->hs_hcon->hdev->block_mtu;
6506 else
6507 chan->conn->mtu = chan->conn->hcon->hdev->acl_mtu;
6508
6509 return l2cap_resegment(chan);
6510 }
6511
6512 static int l2cap_rx_state_wait_p(struct l2cap_chan *chan,
6513 struct l2cap_ctrl *control,
6514 struct sk_buff *skb, u8 event)
6515 {
6516 int err;
6517
6518 BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
6519 event);
6520
6521 if (!control->poll)
6522 return -EPROTO;
6523
6524 l2cap_process_reqseq(chan, control->reqseq);
6525
6526 if (!skb_queue_empty(&chan->tx_q))
6527 chan->tx_send_head = skb_peek(&chan->tx_q);
6528 else
6529 chan->tx_send_head = NULL;
6530
6531 /* Rewind next_tx_seq to the point expected
6532 * by the receiver.
6533 */
6534 chan->next_tx_seq = control->reqseq;
6535 chan->unacked_frames = 0;
6536
6537 err = l2cap_finish_move(chan);
6538 if (err)
6539 return err;
6540
6541 set_bit(CONN_SEND_FBIT, &chan->conn_state);
6542 l2cap_send_i_or_rr_or_rnr(chan);
6543
6544 if (event == L2CAP_EV_RECV_IFRAME)
6545 return -EPROTO;
6546
6547 return l2cap_rx_state_recv(chan, control, NULL, event);
6548 }
6549
6550 static int l2cap_rx_state_wait_f(struct l2cap_chan *chan,
6551 struct l2cap_ctrl *control,
6552 struct sk_buff *skb, u8 event)
6553 {
6554 int err;
6555
6556 if (!control->final)
6557 return -EPROTO;
6558
6559 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6560
6561 chan->rx_state = L2CAP_RX_STATE_RECV;
6562 l2cap_process_reqseq(chan, control->reqseq);
6563
6564 if (!skb_queue_empty(&chan->tx_q))
6565 chan->tx_send_head = skb_peek(&chan->tx_q);
6566 else
6567 chan->tx_send_head = NULL;
6568
6569 /* Rewind next_tx_seq to the point expected
6570 * by the receiver.
6571 */
6572 chan->next_tx_seq = control->reqseq;
6573 chan->unacked_frames = 0;
6574
6575 if (chan->hs_hcon)
6576 chan->conn->mtu = chan->hs_hcon->hdev->block_mtu;
6577 else
6578 chan->conn->mtu = chan->conn->hcon->hdev->acl_mtu;
6579
6580 err = l2cap_resegment(chan);
6581
6582 if (!err)
6583 err = l2cap_rx_state_recv(chan, control, skb, event);
6584
6585 return err;
6586 }
6587
6588 static bool __valid_reqseq(struct l2cap_chan *chan, u16 reqseq)
6589 {
6590 /* Make sure reqseq is for a packet that has been sent but not acked */
6591 u16 unacked;
6592
6593 unacked = __seq_offset(chan, chan->next_tx_seq, chan->expected_ack_seq);
6594 return __seq_offset(chan, chan->next_tx_seq, reqseq) <= unacked;
6595 }
6596
6597 static int l2cap_rx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
6598 struct sk_buff *skb, u8 event)
6599 {
6600 int err = 0;
6601
6602 BT_DBG("chan %p, control %p, skb %p, event %d, state %d", chan,
6603 control, skb, event, chan->rx_state);
6604
6605 if (__valid_reqseq(chan, control->reqseq)) {
6606 switch (chan->rx_state) {
6607 case L2CAP_RX_STATE_RECV:
6608 err = l2cap_rx_state_recv(chan, control, skb, event);
6609 break;
6610 case L2CAP_RX_STATE_SREJ_SENT:
6611 err = l2cap_rx_state_srej_sent(chan, control, skb,
6612 event);
6613 break;
6614 case L2CAP_RX_STATE_WAIT_P:
6615 err = l2cap_rx_state_wait_p(chan, control, skb, event);
6616 break;
6617 case L2CAP_RX_STATE_WAIT_F:
6618 err = l2cap_rx_state_wait_f(chan, control, skb, event);
6619 break;
6620 default:
6621 /* shut it down */
6622 break;
6623 }
6624 } else {
6625 BT_DBG("Invalid reqseq %d (next_tx_seq %d, expected_ack_seq %d",
6626 control->reqseq, chan->next_tx_seq,
6627 chan->expected_ack_seq);
6628 l2cap_send_disconn_req(chan, ECONNRESET);
6629 }
6630
6631 return err;
6632 }
6633
6634 static int l2cap_stream_rx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
6635 struct sk_buff *skb)
6636 {
6637 BT_DBG("chan %p, control %p, skb %p, state %d", chan, control, skb,
6638 chan->rx_state);
6639
6640 if (l2cap_classify_txseq(chan, control->txseq) ==
6641 L2CAP_TXSEQ_EXPECTED) {
6642 l2cap_pass_to_tx(chan, control);
6643
6644 BT_DBG("buffer_seq %d->%d", chan->buffer_seq,
6645 __next_seq(chan, chan->buffer_seq));
6646
6647 chan->buffer_seq = __next_seq(chan, chan->buffer_seq);
6648
6649 l2cap_reassemble_sdu(chan, skb, control);
6650 } else {
6651 if (chan->sdu) {
6652 kfree_skb(chan->sdu);
6653 chan->sdu = NULL;
6654 }
6655 chan->sdu_last_frag = NULL;
6656 chan->sdu_len = 0;
6657
6658 if (skb) {
6659 BT_DBG("Freeing %p", skb);
6660 kfree_skb(skb);
6661 }
6662 }
6663
6664 chan->last_acked_seq = control->txseq;
6665 chan->expected_tx_seq = __next_seq(chan, control->txseq);
6666
6667 return 0;
6668 }
6669
6670 static int l2cap_data_rcv(struct l2cap_chan *chan, struct sk_buff *skb)
6671 {
6672 struct l2cap_ctrl *control = &bt_cb(skb)->l2cap;
6673 u16 len;
6674 u8 event;
6675
6676 __unpack_control(chan, skb);
6677
6678 len = skb->len;
6679
6680 /*
6681 * We can just drop the corrupted I-frame here.
6682 * Receiver will miss it and start proper recovery
6683 * procedures and ask for retransmission.
6684 */
6685 if (l2cap_check_fcs(chan, skb))
6686 goto drop;
6687
6688 if (!control->sframe && control->sar == L2CAP_SAR_START)
6689 len -= L2CAP_SDULEN_SIZE;
6690
6691 if (chan->fcs == L2CAP_FCS_CRC16)
6692 len -= L2CAP_FCS_SIZE;
6693
6694 if (len > chan->mps) {
6695 l2cap_send_disconn_req(chan, ECONNRESET);
6696 goto drop;
6697 }
6698
6699 if ((chan->mode == L2CAP_MODE_ERTM ||
6700 chan->mode == L2CAP_MODE_STREAMING) && sk_filter(chan->data, skb))
6701 goto drop;
6702
6703 if (!control->sframe) {
6704 int err;
6705
6706 BT_DBG("iframe sar %d, reqseq %d, final %d, txseq %d",
6707 control->sar, control->reqseq, control->final,
6708 control->txseq);
6709
6710 /* Validate F-bit - F=0 always valid, F=1 only
6711 * valid in TX WAIT_F
6712 */
6713 if (control->final && chan->tx_state != L2CAP_TX_STATE_WAIT_F)
6714 goto drop;
6715
6716 if (chan->mode != L2CAP_MODE_STREAMING) {
6717 event = L2CAP_EV_RECV_IFRAME;
6718 err = l2cap_rx(chan, control, skb, event);
6719 } else {
6720 err = l2cap_stream_rx(chan, control, skb);
6721 }
6722
6723 if (err)
6724 l2cap_send_disconn_req(chan, ECONNRESET);
6725 } else {
6726 const u8 rx_func_to_event[4] = {
6727 L2CAP_EV_RECV_RR, L2CAP_EV_RECV_REJ,
6728 L2CAP_EV_RECV_RNR, L2CAP_EV_RECV_SREJ
6729 };
6730
6731 /* Only I-frames are expected in streaming mode */
6732 if (chan->mode == L2CAP_MODE_STREAMING)
6733 goto drop;
6734
6735 BT_DBG("sframe reqseq %d, final %d, poll %d, super %d",
6736 control->reqseq, control->final, control->poll,
6737 control->super);
6738
6739 if (len != 0) {
6740 BT_ERR("Trailing bytes: %d in sframe", len);
6741 l2cap_send_disconn_req(chan, ECONNRESET);
6742 goto drop;
6743 }
6744
6745 /* Validate F and P bits */
6746 if (control->final && (control->poll ||
6747 chan->tx_state != L2CAP_TX_STATE_WAIT_F))
6748 goto drop;
6749
6750 event = rx_func_to_event[control->super];
6751 if (l2cap_rx(chan, control, skb, event))
6752 l2cap_send_disconn_req(chan, ECONNRESET);
6753 }
6754
6755 return 0;
6756
6757 drop:
6758 kfree_skb(skb);
6759 return 0;
6760 }
6761
6762 static void l2cap_chan_le_send_credits(struct l2cap_chan *chan)
6763 {
6764 struct l2cap_conn *conn = chan->conn;
6765 struct l2cap_le_credits pkt;
6766 u16 return_credits;
6767
6768 return_credits = ((chan->imtu / chan->mps) + 1) - chan->rx_credits;
6769
6770 if (!return_credits)
6771 return;
6772
6773 BT_DBG("chan %p returning %u credits to sender", chan, return_credits);
6774
6775 chan->rx_credits += return_credits;
6776
6777 pkt.cid = cpu_to_le16(chan->scid);
6778 pkt.credits = cpu_to_le16(return_credits);
6779
6780 chan->ident = l2cap_get_ident(conn);
6781
6782 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CREDITS, sizeof(pkt), &pkt);
6783 }
6784
6785 static int l2cap_le_recv(struct l2cap_chan *chan, struct sk_buff *skb)
6786 {
6787 int err;
6788
6789 BT_DBG("SDU reassemble complete: chan %p skb->len %u", chan, skb->len);
6790
6791 /* Wait recv to confirm reception before updating the credits */
6792 err = chan->ops->recv(chan, skb);
6793
6794 /* Update credits whenever an SDU is received */
6795 l2cap_chan_le_send_credits(chan);
6796
6797 return err;
6798 }
6799
6800 static int l2cap_le_data_rcv(struct l2cap_chan *chan, struct sk_buff *skb)
6801 {
6802 int err;
6803
6804 if (!chan->rx_credits) {
6805 BT_ERR("No credits to receive LE L2CAP data");
6806 l2cap_send_disconn_req(chan, ECONNRESET);
6807 return -ENOBUFS;
6808 }
6809
6810 if (chan->imtu < skb->len) {
6811 BT_ERR("Too big LE L2CAP PDU");
6812 return -ENOBUFS;
6813 }
6814
6815 chan->rx_credits--;
6816 BT_DBG("rx_credits %u -> %u", chan->rx_credits + 1, chan->rx_credits);
6817
6818 /* Update if remote had run out of credits, this should only happens
6819 * if the remote is not using the entire MPS.
6820 */
6821 if (!chan->rx_credits)
6822 l2cap_chan_le_send_credits(chan);
6823
6824 err = 0;
6825
6826 if (!chan->sdu) {
6827 u16 sdu_len;
6828
6829 sdu_len = get_unaligned_le16(skb->data);
6830 skb_pull(skb, L2CAP_SDULEN_SIZE);
6831
6832 BT_DBG("Start of new SDU. sdu_len %u skb->len %u imtu %u",
6833 sdu_len, skb->len, chan->imtu);
6834
6835 if (sdu_len > chan->imtu) {
6836 BT_ERR("Too big LE L2CAP SDU length received");
6837 err = -EMSGSIZE;
6838 goto failed;
6839 }
6840
6841 if (skb->len > sdu_len) {
6842 BT_ERR("Too much LE L2CAP data received");
6843 err = -EINVAL;
6844 goto failed;
6845 }
6846
6847 if (skb->len == sdu_len)
6848 return l2cap_le_recv(chan, skb);
6849
6850 chan->sdu = skb;
6851 chan->sdu_len = sdu_len;
6852 chan->sdu_last_frag = skb;
6853
6854 /* Detect if remote is not able to use the selected MPS */
6855 if (skb->len + L2CAP_SDULEN_SIZE < chan->mps) {
6856 u16 mps_len = skb->len + L2CAP_SDULEN_SIZE;
6857
6858 /* Adjust the number of credits */
6859 BT_DBG("chan->mps %u -> %u", chan->mps, mps_len);
6860 chan->mps = mps_len;
6861 l2cap_chan_le_send_credits(chan);
6862 }
6863
6864 return 0;
6865 }
6866
6867 BT_DBG("SDU fragment. chan->sdu->len %u skb->len %u chan->sdu_len %u",
6868 chan->sdu->len, skb->len, chan->sdu_len);
6869
6870 if (chan->sdu->len + skb->len > chan->sdu_len) {
6871 BT_ERR("Too much LE L2CAP data received");
6872 err = -EINVAL;
6873 goto failed;
6874 }
6875
6876 append_skb_frag(chan->sdu, skb, &chan->sdu_last_frag);
6877 skb = NULL;
6878
6879 if (chan->sdu->len == chan->sdu_len) {
6880 err = l2cap_le_recv(chan, chan->sdu);
6881 if (!err) {
6882 chan->sdu = NULL;
6883 chan->sdu_last_frag = NULL;
6884 chan->sdu_len = 0;
6885 }
6886 }
6887
6888 failed:
6889 if (err) {
6890 kfree_skb(skb);
6891 kfree_skb(chan->sdu);
6892 chan->sdu = NULL;
6893 chan->sdu_last_frag = NULL;
6894 chan->sdu_len = 0;
6895 }
6896
6897 /* We can't return an error here since we took care of the skb
6898 * freeing internally. An error return would cause the caller to
6899 * do a double-free of the skb.
6900 */
6901 return 0;
6902 }
6903
6904 static void l2cap_data_channel(struct l2cap_conn *conn, u16 cid,
6905 struct sk_buff *skb)
6906 {
6907 struct l2cap_chan *chan;
6908
6909 chan = l2cap_get_chan_by_scid(conn, cid);
6910 if (!chan) {
6911 if (cid == L2CAP_CID_A2MP) {
6912 chan = a2mp_channel_create(conn, skb);
6913 if (!chan) {
6914 kfree_skb(skb);
6915 return;
6916 }
6917
6918 l2cap_chan_lock(chan);
6919 } else {
6920 BT_DBG("unknown cid 0x%4.4x", cid);
6921 /* Drop packet and return */
6922 kfree_skb(skb);
6923 return;
6924 }
6925 }
6926
6927 BT_DBG("chan %p, len %d", chan, skb->len);
6928
6929 /* If we receive data on a fixed channel before the info req/rsp
6930 * procdure is done simply assume that the channel is supported
6931 * and mark it as ready.
6932 */
6933 if (chan->chan_type == L2CAP_CHAN_FIXED)
6934 l2cap_chan_ready(chan);
6935
6936 if (chan->state != BT_CONNECTED)
6937 goto drop;
6938
6939 switch (chan->mode) {
6940 case L2CAP_MODE_LE_FLOWCTL:
6941 if (l2cap_le_data_rcv(chan, skb) < 0)
6942 goto drop;
6943
6944 goto done;
6945
6946 case L2CAP_MODE_BASIC:
6947 /* If socket recv buffers overflows we drop data here
6948 * which is *bad* because L2CAP has to be reliable.
6949 * But we don't have any other choice. L2CAP doesn't
6950 * provide flow control mechanism. */
6951
6952 if (chan->imtu < skb->len) {
6953 BT_ERR("Dropping L2CAP data: receive buffer overflow");
6954 goto drop;
6955 }
6956
6957 if (!chan->ops->recv(chan, skb))
6958 goto done;
6959 break;
6960
6961 case L2CAP_MODE_ERTM:
6962 case L2CAP_MODE_STREAMING:
6963 l2cap_data_rcv(chan, skb);
6964 goto done;
6965
6966 default:
6967 BT_DBG("chan %p: bad mode 0x%2.2x", chan, chan->mode);
6968 break;
6969 }
6970
6971 drop:
6972 kfree_skb(skb);
6973
6974 done:
6975 l2cap_chan_unlock(chan);
6976 }
6977
6978 static void l2cap_conless_channel(struct l2cap_conn *conn, __le16 psm,
6979 struct sk_buff *skb)
6980 {
6981 struct hci_conn *hcon = conn->hcon;
6982 struct l2cap_chan *chan;
6983
6984 if (hcon->type != ACL_LINK)
6985 goto free_skb;
6986
6987 chan = l2cap_global_chan_by_psm(0, psm, &hcon->src, &hcon->dst,
6988 ACL_LINK);
6989 if (!chan)
6990 goto free_skb;
6991
6992 BT_DBG("chan %p, len %d", chan, skb->len);
6993
6994 if (chan->state != BT_BOUND && chan->state != BT_CONNECTED)
6995 goto drop;
6996
6997 if (chan->imtu < skb->len)
6998 goto drop;
6999
7000 /* Store remote BD_ADDR and PSM for msg_name */
7001 bacpy(&bt_cb(skb)->l2cap.bdaddr, &hcon->dst);
7002 bt_cb(skb)->l2cap.psm = psm;
7003
7004 if (!chan->ops->recv(chan, skb)) {
7005 l2cap_chan_put(chan);
7006 return;
7007 }
7008
7009 drop:
7010 l2cap_chan_put(chan);
7011 free_skb:
7012 kfree_skb(skb);
7013 }
7014
7015 static void l2cap_recv_frame(struct l2cap_conn *conn, struct sk_buff *skb)
7016 {
7017 struct l2cap_hdr *lh = (void *) skb->data;
7018 struct hci_conn *hcon = conn->hcon;
7019 u16 cid, len;
7020 __le16 psm;
7021
7022 if (hcon->state != BT_CONNECTED) {
7023 BT_DBG("queueing pending rx skb");
7024 skb_queue_tail(&conn->pending_rx, skb);
7025 return;
7026 }
7027
7028 skb_pull(skb, L2CAP_HDR_SIZE);
7029 cid = __le16_to_cpu(lh->cid);
7030 len = __le16_to_cpu(lh->len);
7031
7032 if (len != skb->len) {
7033 kfree_skb(skb);
7034 return;
7035 }
7036
7037 /* Since we can't actively block incoming LE connections we must
7038 * at least ensure that we ignore incoming data from them.
7039 */
7040 if (hcon->type == LE_LINK &&
7041 hci_bdaddr_list_lookup(&hcon->hdev->blacklist, &hcon->dst,
7042 bdaddr_dst_type(hcon))) {
7043 kfree_skb(skb);
7044 return;
7045 }
7046
7047 BT_DBG("len %d, cid 0x%4.4x", len, cid);
7048
7049 switch (cid) {
7050 case L2CAP_CID_SIGNALING:
7051 l2cap_sig_channel(conn, skb);
7052 break;
7053
7054 case L2CAP_CID_CONN_LESS:
7055 psm = get_unaligned((__le16 *) skb->data);
7056 skb_pull(skb, L2CAP_PSMLEN_SIZE);
7057 l2cap_conless_channel(conn, psm, skb);
7058 break;
7059
7060 case L2CAP_CID_LE_SIGNALING:
7061 l2cap_le_sig_channel(conn, skb);
7062 break;
7063
7064 default:
7065 l2cap_data_channel(conn, cid, skb);
7066 break;
7067 }
7068 }
7069
7070 static void process_pending_rx(struct work_struct *work)
7071 {
7072 struct l2cap_conn *conn = container_of(work, struct l2cap_conn,
7073 pending_rx_work);
7074 struct sk_buff *skb;
7075
7076 BT_DBG("");
7077
7078 while ((skb = skb_dequeue(&conn->pending_rx)))
7079 l2cap_recv_frame(conn, skb);
7080 }
7081
7082 static struct l2cap_conn *l2cap_conn_add(struct hci_conn *hcon)
7083 {
7084 struct l2cap_conn *conn = hcon->l2cap_data;
7085 struct hci_chan *hchan;
7086
7087 if (conn)
7088 return conn;
7089
7090 hchan = hci_chan_create(hcon);
7091 if (!hchan)
7092 return NULL;
7093
7094 conn = kzalloc(sizeof(*conn), GFP_KERNEL);
7095 if (!conn) {
7096 hci_chan_del(hchan);
7097 return NULL;
7098 }
7099
7100 kref_init(&conn->ref);
7101 hcon->l2cap_data = conn;
7102 conn->hcon = hci_conn_get(hcon);
7103 conn->hchan = hchan;
7104
7105 BT_DBG("hcon %p conn %p hchan %p", hcon, conn, hchan);
7106
7107 switch (hcon->type) {
7108 case LE_LINK:
7109 if (hcon->hdev->le_mtu) {
7110 conn->mtu = hcon->hdev->le_mtu;
7111 break;
7112 }
7113 /* fall through */
7114 default:
7115 conn->mtu = hcon->hdev->acl_mtu;
7116 break;
7117 }
7118
7119 conn->feat_mask = 0;
7120
7121 conn->local_fixed_chan = L2CAP_FC_SIG_BREDR | L2CAP_FC_CONNLESS;
7122
7123 if (hcon->type == ACL_LINK &&
7124 hci_dev_test_flag(hcon->hdev, HCI_HS_ENABLED))
7125 conn->local_fixed_chan |= L2CAP_FC_A2MP;
7126
7127 if (hci_dev_test_flag(hcon->hdev, HCI_LE_ENABLED) &&
7128 (bredr_sc_enabled(hcon->hdev) ||
7129 hci_dev_test_flag(hcon->hdev, HCI_FORCE_BREDR_SMP)))
7130 conn->local_fixed_chan |= L2CAP_FC_SMP_BREDR;
7131
7132 mutex_init(&conn->ident_lock);
7133 mutex_init(&conn->chan_lock);
7134
7135 INIT_LIST_HEAD(&conn->chan_l);
7136 INIT_LIST_HEAD(&conn->users);
7137
7138 INIT_DELAYED_WORK(&conn->info_timer, l2cap_info_timeout);
7139
7140 skb_queue_head_init(&conn->pending_rx);
7141 INIT_WORK(&conn->pending_rx_work, process_pending_rx);
7142 INIT_WORK(&conn->id_addr_update_work, l2cap_conn_update_id_addr);
7143
7144 conn->disc_reason = HCI_ERROR_REMOTE_USER_TERM;
7145
7146 return conn;
7147 }
7148
7149 static bool is_valid_psm(u16 psm, u8 dst_type) {
7150 if (!psm)
7151 return false;
7152
7153 if (bdaddr_type_is_le(dst_type))
7154 return (psm <= 0x00ff);
7155
7156 /* PSM must be odd and lsb of upper byte must be 0 */
7157 return ((psm & 0x0101) == 0x0001);
7158 }
7159
7160 int l2cap_chan_connect(struct l2cap_chan *chan, __le16 psm, u16 cid,
7161 bdaddr_t *dst, u8 dst_type)
7162 {
7163 struct l2cap_conn *conn;
7164 struct hci_conn *hcon;
7165 struct hci_dev *hdev;
7166 int err;
7167
7168 BT_DBG("%pMR -> %pMR (type %u) psm 0x%2.2x", &chan->src, dst,
7169 dst_type, __le16_to_cpu(psm));
7170
7171 hdev = hci_get_route(dst, &chan->src, chan->src_type);
7172 if (!hdev)
7173 return -EHOSTUNREACH;
7174
7175 hci_dev_lock(hdev);
7176
7177 if (!is_valid_psm(__le16_to_cpu(psm), dst_type) && !cid &&
7178 chan->chan_type != L2CAP_CHAN_RAW) {
7179 err = -EINVAL;
7180 goto done;
7181 }
7182
7183 if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED && !psm) {
7184 err = -EINVAL;
7185 goto done;
7186 }
7187
7188 if (chan->chan_type == L2CAP_CHAN_FIXED && !cid) {
7189 err = -EINVAL;
7190 goto done;
7191 }
7192
7193 switch (chan->mode) {
7194 case L2CAP_MODE_BASIC:
7195 break;
7196 case L2CAP_MODE_LE_FLOWCTL:
7197 break;
7198 case L2CAP_MODE_ERTM:
7199 case L2CAP_MODE_STREAMING:
7200 if (!disable_ertm)
7201 break;
7202 /* fall through */
7203 default:
7204 err = -EOPNOTSUPP;
7205 goto done;
7206 }
7207
7208 switch (chan->state) {
7209 case BT_CONNECT:
7210 case BT_CONNECT2:
7211 case BT_CONFIG:
7212 /* Already connecting */
7213 err = 0;
7214 goto done;
7215
7216 case BT_CONNECTED:
7217 /* Already connected */
7218 err = -EISCONN;
7219 goto done;
7220
7221 case BT_OPEN:
7222 case BT_BOUND:
7223 /* Can connect */
7224 break;
7225
7226 default:
7227 err = -EBADFD;
7228 goto done;
7229 }
7230
7231 /* Set destination address and psm */
7232 bacpy(&chan->dst, dst);
7233 chan->dst_type = dst_type;
7234
7235 chan->psm = psm;
7236 chan->dcid = cid;
7237
7238 if (bdaddr_type_is_le(dst_type)) {
7239 /* Convert from L2CAP channel address type to HCI address type
7240 */
7241 if (dst_type == BDADDR_LE_PUBLIC)
7242 dst_type = ADDR_LE_DEV_PUBLIC;
7243 else
7244 dst_type = ADDR_LE_DEV_RANDOM;
7245
7246 if (hci_dev_test_flag(hdev, HCI_ADVERTISING))
7247 hcon = hci_connect_le(hdev, dst, dst_type,
7248 chan->sec_level,
7249 HCI_LE_CONN_TIMEOUT,
7250 HCI_ROLE_SLAVE, NULL);
7251 else
7252 hcon = hci_connect_le_scan(hdev, dst, dst_type,
7253 chan->sec_level,
7254 HCI_LE_CONN_TIMEOUT);
7255
7256 } else {
7257 u8 auth_type = l2cap_get_auth_type(chan);
7258 hcon = hci_connect_acl(hdev, dst, chan->sec_level, auth_type);
7259 }
7260
7261 if (IS_ERR(hcon)) {
7262 err = PTR_ERR(hcon);
7263 goto done;
7264 }
7265
7266 conn = l2cap_conn_add(hcon);
7267 if (!conn) {
7268 hci_conn_drop(hcon);
7269 err = -ENOMEM;
7270 goto done;
7271 }
7272
7273 mutex_lock(&conn->chan_lock);
7274 l2cap_chan_lock(chan);
7275
7276 if (cid && __l2cap_get_chan_by_dcid(conn, cid)) {
7277 hci_conn_drop(hcon);
7278 err = -EBUSY;
7279 goto chan_unlock;
7280 }
7281
7282 /* Update source addr of the socket */
7283 bacpy(&chan->src, &hcon->src);
7284 chan->src_type = bdaddr_src_type(hcon);
7285
7286 __l2cap_chan_add(conn, chan);
7287
7288 /* l2cap_chan_add takes its own ref so we can drop this one */
7289 hci_conn_drop(hcon);
7290
7291 l2cap_state_change(chan, BT_CONNECT);
7292 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
7293
7294 /* Release chan->sport so that it can be reused by other
7295 * sockets (as it's only used for listening sockets).
7296 */
7297 write_lock(&chan_list_lock);
7298 chan->sport = 0;
7299 write_unlock(&chan_list_lock);
7300
7301 if (hcon->state == BT_CONNECTED) {
7302 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
7303 __clear_chan_timer(chan);
7304 if (l2cap_chan_check_security(chan, true))
7305 l2cap_state_change(chan, BT_CONNECTED);
7306 } else
7307 l2cap_do_start(chan);
7308 }
7309
7310 err = 0;
7311
7312 chan_unlock:
7313 l2cap_chan_unlock(chan);
7314 mutex_unlock(&conn->chan_lock);
7315 done:
7316 hci_dev_unlock(hdev);
7317 hci_dev_put(hdev);
7318 return err;
7319 }
7320 EXPORT_SYMBOL_GPL(l2cap_chan_connect);
7321
7322 /* ---- L2CAP interface with lower layer (HCI) ---- */
7323
7324 int l2cap_connect_ind(struct hci_dev *hdev, bdaddr_t *bdaddr)
7325 {
7326 int exact = 0, lm1 = 0, lm2 = 0;
7327 struct l2cap_chan *c;
7328
7329 BT_DBG("hdev %s, bdaddr %pMR", hdev->name, bdaddr);
7330
7331 /* Find listening sockets and check their link_mode */
7332 read_lock(&chan_list_lock);
7333 list_for_each_entry(c, &chan_list, global_l) {
7334 if (c->state != BT_LISTEN)
7335 continue;
7336
7337 if (!bacmp(&c->src, &hdev->bdaddr)) {
7338 lm1 |= HCI_LM_ACCEPT;
7339 if (test_bit(FLAG_ROLE_SWITCH, &c->flags))
7340 lm1 |= HCI_LM_MASTER;
7341 exact++;
7342 } else if (!bacmp(&c->src, BDADDR_ANY)) {
7343 lm2 |= HCI_LM_ACCEPT;
7344 if (test_bit(FLAG_ROLE_SWITCH, &c->flags))
7345 lm2 |= HCI_LM_MASTER;
7346 }
7347 }
7348 read_unlock(&chan_list_lock);
7349
7350 return exact ? lm1 : lm2;
7351 }
7352
7353 /* Find the next fixed channel in BT_LISTEN state, continue iteration
7354 * from an existing channel in the list or from the beginning of the
7355 * global list (by passing NULL as first parameter).
7356 */
7357 static struct l2cap_chan *l2cap_global_fixed_chan(struct l2cap_chan *c,
7358 struct hci_conn *hcon)
7359 {
7360 u8 src_type = bdaddr_src_type(hcon);
7361
7362 read_lock(&chan_list_lock);
7363
7364 if (c)
7365 c = list_next_entry(c, global_l);
7366 else
7367 c = list_entry(chan_list.next, typeof(*c), global_l);
7368
7369 list_for_each_entry_from(c, &chan_list, global_l) {
7370 if (c->chan_type != L2CAP_CHAN_FIXED)
7371 continue;
7372 if (c->state != BT_LISTEN)
7373 continue;
7374 if (bacmp(&c->src, &hcon->src) && bacmp(&c->src, BDADDR_ANY))
7375 continue;
7376 if (src_type != c->src_type)
7377 continue;
7378
7379 l2cap_chan_hold(c);
7380 read_unlock(&chan_list_lock);
7381 return c;
7382 }
7383
7384 read_unlock(&chan_list_lock);
7385
7386 return NULL;
7387 }
7388
7389 static void l2cap_connect_cfm(struct hci_conn *hcon, u8 status)
7390 {
7391 struct hci_dev *hdev = hcon->hdev;
7392 struct l2cap_conn *conn;
7393 struct l2cap_chan *pchan;
7394 u8 dst_type;
7395
7396 if (hcon->type != ACL_LINK && hcon->type != LE_LINK)
7397 return;
7398
7399 BT_DBG("hcon %p bdaddr %pMR status %d", hcon, &hcon->dst, status);
7400
7401 if (status) {
7402 l2cap_conn_del(hcon, bt_to_errno(status));
7403 return;
7404 }
7405
7406 conn = l2cap_conn_add(hcon);
7407 if (!conn)
7408 return;
7409
7410 dst_type = bdaddr_dst_type(hcon);
7411
7412 /* If device is blocked, do not create channels for it */
7413 if (hci_bdaddr_list_lookup(&hdev->blacklist, &hcon->dst, dst_type))
7414 return;
7415
7416 /* Find fixed channels and notify them of the new connection. We
7417 * use multiple individual lookups, continuing each time where
7418 * we left off, because the list lock would prevent calling the
7419 * potentially sleeping l2cap_chan_lock() function.
7420 */
7421 pchan = l2cap_global_fixed_chan(NULL, hcon);
7422 while (pchan) {
7423 struct l2cap_chan *chan, *next;
7424
7425 /* Client fixed channels should override server ones */
7426 if (__l2cap_get_chan_by_dcid(conn, pchan->scid))
7427 goto next;
7428
7429 l2cap_chan_lock(pchan);
7430 chan = pchan->ops->new_connection(pchan);
7431 if (chan) {
7432 bacpy(&chan->src, &hcon->src);
7433 bacpy(&chan->dst, &hcon->dst);
7434 chan->src_type = bdaddr_src_type(hcon);
7435 chan->dst_type = dst_type;
7436
7437 __l2cap_chan_add(conn, chan);
7438 }
7439
7440 l2cap_chan_unlock(pchan);
7441 next:
7442 next = l2cap_global_fixed_chan(pchan, hcon);
7443 l2cap_chan_put(pchan);
7444 pchan = next;
7445 }
7446
7447 l2cap_conn_ready(conn);
7448 }
7449
7450 int l2cap_disconn_ind(struct hci_conn *hcon)
7451 {
7452 struct l2cap_conn *conn = hcon->l2cap_data;
7453
7454 BT_DBG("hcon %p", hcon);
7455
7456 if (!conn)
7457 return HCI_ERROR_REMOTE_USER_TERM;
7458 return conn->disc_reason;
7459 }
7460
7461 static void l2cap_disconn_cfm(struct hci_conn *hcon, u8 reason)
7462 {
7463 if (hcon->type != ACL_LINK && hcon->type != LE_LINK)
7464 return;
7465
7466 BT_DBG("hcon %p reason %d", hcon, reason);
7467
7468 l2cap_conn_del(hcon, bt_to_errno(reason));
7469 }
7470
7471 static inline void l2cap_check_encryption(struct l2cap_chan *chan, u8 encrypt)
7472 {
7473 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED)
7474 return;
7475
7476 if (encrypt == 0x00) {
7477 if (chan->sec_level == BT_SECURITY_MEDIUM) {
7478 __set_chan_timer(chan, L2CAP_ENC_TIMEOUT);
7479 } else if (chan->sec_level == BT_SECURITY_HIGH ||
7480 chan->sec_level == BT_SECURITY_FIPS)
7481 l2cap_chan_close(chan, ECONNREFUSED);
7482 } else {
7483 if (chan->sec_level == BT_SECURITY_MEDIUM)
7484 __clear_chan_timer(chan);
7485 }
7486 }
7487
7488 static void l2cap_security_cfm(struct hci_conn *hcon, u8 status, u8 encrypt)
7489 {
7490 struct l2cap_conn *conn = hcon->l2cap_data;
7491 struct l2cap_chan *chan;
7492
7493 if (!conn)
7494 return;
7495
7496 BT_DBG("conn %p status 0x%2.2x encrypt %u", conn, status, encrypt);
7497
7498 mutex_lock(&conn->chan_lock);
7499
7500 list_for_each_entry(chan, &conn->chan_l, list) {
7501 l2cap_chan_lock(chan);
7502
7503 BT_DBG("chan %p scid 0x%4.4x state %s", chan, chan->scid,
7504 state_to_string(chan->state));
7505
7506 if (chan->scid == L2CAP_CID_A2MP) {
7507 l2cap_chan_unlock(chan);
7508 continue;
7509 }
7510
7511 if (!status && encrypt)
7512 chan->sec_level = hcon->sec_level;
7513
7514 if (!__l2cap_no_conn_pending(chan)) {
7515 l2cap_chan_unlock(chan);
7516 continue;
7517 }
7518
7519 if (!status && (chan->state == BT_CONNECTED ||
7520 chan->state == BT_CONFIG)) {
7521 chan->ops->resume(chan);
7522 l2cap_check_encryption(chan, encrypt);
7523 l2cap_chan_unlock(chan);
7524 continue;
7525 }
7526
7527 if (chan->state == BT_CONNECT) {
7528 if (!status && l2cap_check_enc_key_size(hcon))
7529 l2cap_start_connection(chan);
7530 else
7531 __set_chan_timer(chan, L2CAP_DISC_TIMEOUT);
7532 } else if (chan->state == BT_CONNECT2 &&
7533 chan->mode != L2CAP_MODE_LE_FLOWCTL) {
7534 struct l2cap_conn_rsp rsp;
7535 __u16 res, stat;
7536
7537 if (!status && l2cap_check_enc_key_size(hcon)) {
7538 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
7539 res = L2CAP_CR_PEND;
7540 stat = L2CAP_CS_AUTHOR_PEND;
7541 chan->ops->defer(chan);
7542 } else {
7543 l2cap_state_change(chan, BT_CONFIG);
7544 res = L2CAP_CR_SUCCESS;
7545 stat = L2CAP_CS_NO_INFO;
7546 }
7547 } else {
7548 l2cap_state_change(chan, BT_DISCONN);
7549 __set_chan_timer(chan, L2CAP_DISC_TIMEOUT);
7550 res = L2CAP_CR_SEC_BLOCK;
7551 stat = L2CAP_CS_NO_INFO;
7552 }
7553
7554 rsp.scid = cpu_to_le16(chan->dcid);
7555 rsp.dcid = cpu_to_le16(chan->scid);
7556 rsp.result = cpu_to_le16(res);
7557 rsp.status = cpu_to_le16(stat);
7558 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP,
7559 sizeof(rsp), &rsp);
7560
7561 if (!test_bit(CONF_REQ_SENT, &chan->conf_state) &&
7562 res == L2CAP_CR_SUCCESS) {
7563 char buf[128];
7564 set_bit(CONF_REQ_SENT, &chan->conf_state);
7565 l2cap_send_cmd(conn, l2cap_get_ident(conn),
7566 L2CAP_CONF_REQ,
7567 l2cap_build_conf_req(chan, buf, sizeof(buf)),
7568 buf);
7569 chan->num_conf_req++;
7570 }
7571 }
7572
7573 l2cap_chan_unlock(chan);
7574 }
7575
7576 mutex_unlock(&conn->chan_lock);
7577 }
7578
7579 void l2cap_recv_acldata(struct hci_conn *hcon, struct sk_buff *skb, u16 flags)
7580 {
7581 struct l2cap_conn *conn = hcon->l2cap_data;
7582 struct l2cap_hdr *hdr;
7583 int len;
7584
7585 /* For AMP controller do not create l2cap conn */
7586 if (!conn && hcon->hdev->dev_type != HCI_PRIMARY)
7587 goto drop;
7588
7589 if (!conn)
7590 conn = l2cap_conn_add(hcon);
7591
7592 if (!conn)
7593 goto drop;
7594
7595 BT_DBG("conn %p len %d flags 0x%x", conn, skb->len, flags);
7596
7597 switch (flags) {
7598 case ACL_START:
7599 case ACL_START_NO_FLUSH:
7600 case ACL_COMPLETE:
7601 if (conn->rx_len) {
7602 BT_ERR("Unexpected start frame (len %d)", skb->len);
7603 kfree_skb(conn->rx_skb);
7604 conn->rx_skb = NULL;
7605 conn->rx_len = 0;
7606 l2cap_conn_unreliable(conn, ECOMM);
7607 }
7608
7609 /* Start fragment always begin with Basic L2CAP header */
7610 if (skb->len < L2CAP_HDR_SIZE) {
7611 BT_ERR("Frame is too short (len %d)", skb->len);
7612 l2cap_conn_unreliable(conn, ECOMM);
7613 goto drop;
7614 }
7615
7616 hdr = (struct l2cap_hdr *) skb->data;
7617 len = __le16_to_cpu(hdr->len) + L2CAP_HDR_SIZE;
7618
7619 if (len == skb->len) {
7620 /* Complete frame received */
7621 l2cap_recv_frame(conn, skb);
7622 return;
7623 }
7624
7625 BT_DBG("Start: total len %d, frag len %d", len, skb->len);
7626
7627 if (skb->len > len) {
7628 BT_ERR("Frame is too long (len %d, expected len %d)",
7629 skb->len, len);
7630 l2cap_conn_unreliable(conn, ECOMM);
7631 goto drop;
7632 }
7633
7634 /* Allocate skb for the complete frame (with header) */
7635 conn->rx_skb = bt_skb_alloc(len, GFP_KERNEL);
7636 if (!conn->rx_skb)
7637 goto drop;
7638
7639 skb_copy_from_linear_data(skb, skb_put(conn->rx_skb, skb->len),
7640 skb->len);
7641 conn->rx_len = len - skb->len;
7642 break;
7643
7644 case ACL_CONT:
7645 BT_DBG("Cont: frag len %d (expecting %d)", skb->len, conn->rx_len);
7646
7647 if (!conn->rx_len) {
7648 BT_ERR("Unexpected continuation frame (len %d)", skb->len);
7649 l2cap_conn_unreliable(conn, ECOMM);
7650 goto drop;
7651 }
7652
7653 if (skb->len > conn->rx_len) {
7654 BT_ERR("Fragment is too long (len %d, expected %d)",
7655 skb->len, conn->rx_len);
7656 kfree_skb(conn->rx_skb);
7657 conn->rx_skb = NULL;
7658 conn->rx_len = 0;
7659 l2cap_conn_unreliable(conn, ECOMM);
7660 goto drop;
7661 }
7662
7663 skb_copy_from_linear_data(skb, skb_put(conn->rx_skb, skb->len),
7664 skb->len);
7665 conn->rx_len -= skb->len;
7666
7667 if (!conn->rx_len) {
7668 /* Complete frame received. l2cap_recv_frame
7669 * takes ownership of the skb so set the global
7670 * rx_skb pointer to NULL first.
7671 */
7672 struct sk_buff *rx_skb = conn->rx_skb;
7673 conn->rx_skb = NULL;
7674 l2cap_recv_frame(conn, rx_skb);
7675 }
7676 break;
7677 }
7678
7679 drop:
7680 kfree_skb(skb);
7681 }
7682
7683 static struct hci_cb l2cap_cb = {
7684 .name = "L2CAP",
7685 .connect_cfm = l2cap_connect_cfm,
7686 .disconn_cfm = l2cap_disconn_cfm,
7687 .security_cfm = l2cap_security_cfm,
7688 };
7689
7690 static int l2cap_debugfs_show(struct seq_file *f, void *p)
7691 {
7692 struct l2cap_chan *c;
7693
7694 read_lock(&chan_list_lock);
7695
7696 list_for_each_entry(c, &chan_list, global_l) {
7697 seq_printf(f, "%pMR (%u) %pMR (%u) %d %d 0x%4.4x 0x%4.4x %d %d %d %d\n",
7698 &c->src, c->src_type, &c->dst, c->dst_type,
7699 c->state, __le16_to_cpu(c->psm),
7700 c->scid, c->dcid, c->imtu, c->omtu,
7701 c->sec_level, c->mode);
7702 }
7703
7704 read_unlock(&chan_list_lock);
7705
7706 return 0;
7707 }
7708
7709 DEFINE_SHOW_ATTRIBUTE(l2cap_debugfs);
7710
7711 static struct dentry *l2cap_debugfs;
7712
7713 int __init l2cap_init(void)
7714 {
7715 int err;
7716
7717 err = l2cap_init_sockets();
7718 if (err < 0)
7719 return err;
7720
7721 hci_register_cb(&l2cap_cb);
7722
7723 if (IS_ERR_OR_NULL(bt_debugfs))
7724 return 0;
7725
7726 l2cap_debugfs = debugfs_create_file("l2cap", 0444, bt_debugfs,
7727 NULL, &l2cap_debugfs_fops);
7728
7729 return 0;
7730 }
7731
7732 void l2cap_exit(void)
7733 {
7734 debugfs_remove(l2cap_debugfs);
7735 hci_unregister_cb(&l2cap_cb);
7736 l2cap_cleanup_sockets();
7737 }
7738
7739 module_param(disable_ertm, bool, 0644);
7740 MODULE_PARM_DESC(disable_ertm, "Disable enhanced retransmission mode");
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