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[thirdparty/linux.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 l2cap_chan_unlock(chan);
4941 return;
4942 }
4943
4944 if (chan->state != BT_CONNECTED) {
4945 l2cap_do_create(chan, result, local_amp_id, remote_amp_id);
4946 } else if (result != L2CAP_MR_SUCCESS) {
4947 l2cap_do_move_cancel(chan, result);
4948 } else {
4949 switch (chan->move_role) {
4950 case L2CAP_MOVE_ROLE_INITIATOR:
4951 l2cap_do_move_initiate(chan, local_amp_id,
4952 remote_amp_id);
4953 break;
4954 case L2CAP_MOVE_ROLE_RESPONDER:
4955 l2cap_do_move_respond(chan, result);
4956 break;
4957 default:
4958 l2cap_do_move_cancel(chan, result);
4959 break;
4960 }
4961 }
4962 }
4963
4964 static inline int l2cap_move_channel_req(struct l2cap_conn *conn,
4965 struct l2cap_cmd_hdr *cmd,
4966 u16 cmd_len, void *data)
4967 {
4968 struct l2cap_move_chan_req *req = data;
4969 struct l2cap_move_chan_rsp rsp;
4970 struct l2cap_chan *chan;
4971 u16 icid = 0;
4972 u16 result = L2CAP_MR_NOT_ALLOWED;
4973
4974 if (cmd_len != sizeof(*req))
4975 return -EPROTO;
4976
4977 icid = le16_to_cpu(req->icid);
4978
4979 BT_DBG("icid 0x%4.4x, dest_amp_id %d", icid, req->dest_amp_id);
4980
4981 if (!(conn->local_fixed_chan & L2CAP_FC_A2MP))
4982 return -EINVAL;
4983
4984 chan = l2cap_get_chan_by_dcid(conn, icid);
4985 if (!chan) {
4986 rsp.icid = cpu_to_le16(icid);
4987 rsp.result = cpu_to_le16(L2CAP_MR_NOT_ALLOWED);
4988 l2cap_send_cmd(conn, cmd->ident, L2CAP_MOVE_CHAN_RSP,
4989 sizeof(rsp), &rsp);
4990 return 0;
4991 }
4992
4993 chan->ident = cmd->ident;
4994
4995 if (chan->scid < L2CAP_CID_DYN_START ||
4996 chan->chan_policy == BT_CHANNEL_POLICY_BREDR_ONLY ||
4997 (chan->mode != L2CAP_MODE_ERTM &&
4998 chan->mode != L2CAP_MODE_STREAMING)) {
4999 result = L2CAP_MR_NOT_ALLOWED;
5000 goto send_move_response;
5001 }
5002
5003 if (chan->local_amp_id == req->dest_amp_id) {
5004 result = L2CAP_MR_SAME_ID;
5005 goto send_move_response;
5006 }
5007
5008 if (req->dest_amp_id != AMP_ID_BREDR) {
5009 struct hci_dev *hdev;
5010 hdev = hci_dev_get(req->dest_amp_id);
5011 if (!hdev || hdev->dev_type != HCI_AMP ||
5012 !test_bit(HCI_UP, &hdev->flags)) {
5013 if (hdev)
5014 hci_dev_put(hdev);
5015
5016 result = L2CAP_MR_BAD_ID;
5017 goto send_move_response;
5018 }
5019 hci_dev_put(hdev);
5020 }
5021
5022 /* Detect a move collision. Only send a collision response
5023 * if this side has "lost", otherwise proceed with the move.
5024 * The winner has the larger bd_addr.
5025 */
5026 if ((__chan_is_moving(chan) ||
5027 chan->move_role != L2CAP_MOVE_ROLE_NONE) &&
5028 bacmp(&conn->hcon->src, &conn->hcon->dst) > 0) {
5029 result = L2CAP_MR_COLLISION;
5030 goto send_move_response;
5031 }
5032
5033 chan->move_role = L2CAP_MOVE_ROLE_RESPONDER;
5034 l2cap_move_setup(chan);
5035 chan->move_id = req->dest_amp_id;
5036 icid = chan->dcid;
5037
5038 if (req->dest_amp_id == AMP_ID_BREDR) {
5039 /* Moving to BR/EDR */
5040 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
5041 chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
5042 result = L2CAP_MR_PEND;
5043 } else {
5044 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
5045 result = L2CAP_MR_SUCCESS;
5046 }
5047 } else {
5048 chan->move_state = L2CAP_MOVE_WAIT_PREPARE;
5049 /* Placeholder - uncomment when amp functions are available */
5050 /*amp_accept_physical(chan, req->dest_amp_id);*/
5051 result = L2CAP_MR_PEND;
5052 }
5053
5054 send_move_response:
5055 l2cap_send_move_chan_rsp(chan, result);
5056
5057 l2cap_chan_unlock(chan);
5058
5059 return 0;
5060 }
5061
5062 static void l2cap_move_continue(struct l2cap_conn *conn, u16 icid, u16 result)
5063 {
5064 struct l2cap_chan *chan;
5065 struct hci_chan *hchan = NULL;
5066
5067 chan = l2cap_get_chan_by_scid(conn, icid);
5068 if (!chan) {
5069 l2cap_send_move_chan_cfm_icid(conn, icid);
5070 return;
5071 }
5072
5073 __clear_chan_timer(chan);
5074 if (result == L2CAP_MR_PEND)
5075 __set_chan_timer(chan, L2CAP_MOVE_ERTX_TIMEOUT);
5076
5077 switch (chan->move_state) {
5078 case L2CAP_MOVE_WAIT_LOGICAL_COMP:
5079 /* Move confirm will be sent when logical link
5080 * is complete.
5081 */
5082 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
5083 break;
5084 case L2CAP_MOVE_WAIT_RSP_SUCCESS:
5085 if (result == L2CAP_MR_PEND) {
5086 break;
5087 } else if (test_bit(CONN_LOCAL_BUSY,
5088 &chan->conn_state)) {
5089 chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
5090 } else {
5091 /* Logical link is up or moving to BR/EDR,
5092 * proceed with move
5093 */
5094 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM_RSP;
5095 l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
5096 }
5097 break;
5098 case L2CAP_MOVE_WAIT_RSP:
5099 /* Moving to AMP */
5100 if (result == L2CAP_MR_SUCCESS) {
5101 /* Remote is ready, send confirm immediately
5102 * after logical link is ready
5103 */
5104 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
5105 } else {
5106 /* Both logical link and move success
5107 * are required to confirm
5108 */
5109 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_COMP;
5110 }
5111
5112 /* Placeholder - get hci_chan for logical link */
5113 if (!hchan) {
5114 /* Logical link not available */
5115 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5116 break;
5117 }
5118
5119 /* If the logical link is not yet connected, do not
5120 * send confirmation.
5121 */
5122 if (hchan->state != BT_CONNECTED)
5123 break;
5124
5125 /* Logical link is already ready to go */
5126
5127 chan->hs_hcon = hchan->conn;
5128 chan->hs_hcon->l2cap_data = chan->conn;
5129
5130 if (result == L2CAP_MR_SUCCESS) {
5131 /* Can confirm now */
5132 l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
5133 } else {
5134 /* Now only need move success
5135 * to confirm
5136 */
5137 chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
5138 }
5139
5140 l2cap_logical_cfm(chan, hchan, L2CAP_MR_SUCCESS);
5141 break;
5142 default:
5143 /* Any other amp move state means the move failed. */
5144 chan->move_id = chan->local_amp_id;
5145 l2cap_move_done(chan);
5146 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5147 }
5148
5149 l2cap_chan_unlock(chan);
5150 }
5151
5152 static void l2cap_move_fail(struct l2cap_conn *conn, u8 ident, u16 icid,
5153 u16 result)
5154 {
5155 struct l2cap_chan *chan;
5156
5157 chan = l2cap_get_chan_by_ident(conn, ident);
5158 if (!chan) {
5159 /* Could not locate channel, icid is best guess */
5160 l2cap_send_move_chan_cfm_icid(conn, icid);
5161 return;
5162 }
5163
5164 __clear_chan_timer(chan);
5165
5166 if (chan->move_role == L2CAP_MOVE_ROLE_INITIATOR) {
5167 if (result == L2CAP_MR_COLLISION) {
5168 chan->move_role = L2CAP_MOVE_ROLE_RESPONDER;
5169 } else {
5170 /* Cleanup - cancel move */
5171 chan->move_id = chan->local_amp_id;
5172 l2cap_move_done(chan);
5173 }
5174 }
5175
5176 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5177
5178 l2cap_chan_unlock(chan);
5179 }
5180
5181 static int l2cap_move_channel_rsp(struct l2cap_conn *conn,
5182 struct l2cap_cmd_hdr *cmd,
5183 u16 cmd_len, void *data)
5184 {
5185 struct l2cap_move_chan_rsp *rsp = data;
5186 u16 icid, result;
5187
5188 if (cmd_len != sizeof(*rsp))
5189 return -EPROTO;
5190
5191 icid = le16_to_cpu(rsp->icid);
5192 result = le16_to_cpu(rsp->result);
5193
5194 BT_DBG("icid 0x%4.4x, result 0x%4.4x", icid, result);
5195
5196 if (result == L2CAP_MR_SUCCESS || result == L2CAP_MR_PEND)
5197 l2cap_move_continue(conn, icid, result);
5198 else
5199 l2cap_move_fail(conn, cmd->ident, icid, result);
5200
5201 return 0;
5202 }
5203
5204 static int l2cap_move_channel_confirm(struct l2cap_conn *conn,
5205 struct l2cap_cmd_hdr *cmd,
5206 u16 cmd_len, void *data)
5207 {
5208 struct l2cap_move_chan_cfm *cfm = data;
5209 struct l2cap_chan *chan;
5210 u16 icid, result;
5211
5212 if (cmd_len != sizeof(*cfm))
5213 return -EPROTO;
5214
5215 icid = le16_to_cpu(cfm->icid);
5216 result = le16_to_cpu(cfm->result);
5217
5218 BT_DBG("icid 0x%4.4x, result 0x%4.4x", icid, result);
5219
5220 chan = l2cap_get_chan_by_dcid(conn, icid);
5221 if (!chan) {
5222 /* Spec requires a response even if the icid was not found */
5223 l2cap_send_move_chan_cfm_rsp(conn, cmd->ident, icid);
5224 return 0;
5225 }
5226
5227 if (chan->move_state == L2CAP_MOVE_WAIT_CONFIRM) {
5228 if (result == L2CAP_MC_CONFIRMED) {
5229 chan->local_amp_id = chan->move_id;
5230 if (chan->local_amp_id == AMP_ID_BREDR)
5231 __release_logical_link(chan);
5232 } else {
5233 chan->move_id = chan->local_amp_id;
5234 }
5235
5236 l2cap_move_done(chan);
5237 }
5238
5239 l2cap_send_move_chan_cfm_rsp(conn, cmd->ident, icid);
5240
5241 l2cap_chan_unlock(chan);
5242
5243 return 0;
5244 }
5245
5246 static inline int l2cap_move_channel_confirm_rsp(struct l2cap_conn *conn,
5247 struct l2cap_cmd_hdr *cmd,
5248 u16 cmd_len, void *data)
5249 {
5250 struct l2cap_move_chan_cfm_rsp *rsp = data;
5251 struct l2cap_chan *chan;
5252 u16 icid;
5253
5254 if (cmd_len != sizeof(*rsp))
5255 return -EPROTO;
5256
5257 icid = le16_to_cpu(rsp->icid);
5258
5259 BT_DBG("icid 0x%4.4x", icid);
5260
5261 chan = l2cap_get_chan_by_scid(conn, icid);
5262 if (!chan)
5263 return 0;
5264
5265 __clear_chan_timer(chan);
5266
5267 if (chan->move_state == L2CAP_MOVE_WAIT_CONFIRM_RSP) {
5268 chan->local_amp_id = chan->move_id;
5269
5270 if (chan->local_amp_id == AMP_ID_BREDR && chan->hs_hchan)
5271 __release_logical_link(chan);
5272
5273 l2cap_move_done(chan);
5274 }
5275
5276 l2cap_chan_unlock(chan);
5277
5278 return 0;
5279 }
5280
5281 static inline int l2cap_conn_param_update_req(struct l2cap_conn *conn,
5282 struct l2cap_cmd_hdr *cmd,
5283 u16 cmd_len, u8 *data)
5284 {
5285 struct hci_conn *hcon = conn->hcon;
5286 struct l2cap_conn_param_update_req *req;
5287 struct l2cap_conn_param_update_rsp rsp;
5288 u16 min, max, latency, to_multiplier;
5289 int err;
5290
5291 if (hcon->role != HCI_ROLE_MASTER)
5292 return -EINVAL;
5293
5294 if (cmd_len != sizeof(struct l2cap_conn_param_update_req))
5295 return -EPROTO;
5296
5297 req = (struct l2cap_conn_param_update_req *) data;
5298 min = __le16_to_cpu(req->min);
5299 max = __le16_to_cpu(req->max);
5300 latency = __le16_to_cpu(req->latency);
5301 to_multiplier = __le16_to_cpu(req->to_multiplier);
5302
5303 BT_DBG("min 0x%4.4x max 0x%4.4x latency: 0x%4.4x Timeout: 0x%4.4x",
5304 min, max, latency, to_multiplier);
5305
5306 memset(&rsp, 0, sizeof(rsp));
5307
5308 if (min < hcon->le_conn_min_interval ||
5309 max > hcon->le_conn_max_interval) {
5310 BT_DBG("requested connection interval exceeds current bounds.");
5311 err = -EINVAL;
5312 } else {
5313 err = hci_check_conn_params(min, max, latency, to_multiplier);
5314 }
5315
5316 if (err)
5317 rsp.result = cpu_to_le16(L2CAP_CONN_PARAM_REJECTED);
5318 else
5319 rsp.result = cpu_to_le16(L2CAP_CONN_PARAM_ACCEPTED);
5320
5321 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONN_PARAM_UPDATE_RSP,
5322 sizeof(rsp), &rsp);
5323
5324 if (!err) {
5325 u8 store_hint;
5326
5327 store_hint = hci_le_conn_update(hcon, min, max, latency,
5328 to_multiplier);
5329 mgmt_new_conn_param(hcon->hdev, &hcon->dst, hcon->dst_type,
5330 store_hint, min, max, latency,
5331 to_multiplier);
5332
5333 }
5334
5335 return 0;
5336 }
5337
5338 static int l2cap_le_connect_rsp(struct l2cap_conn *conn,
5339 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5340 u8 *data)
5341 {
5342 struct l2cap_le_conn_rsp *rsp = (struct l2cap_le_conn_rsp *) data;
5343 struct hci_conn *hcon = conn->hcon;
5344 u16 dcid, mtu, mps, credits, result;
5345 struct l2cap_chan *chan;
5346 int err, sec_level;
5347
5348 if (cmd_len < sizeof(*rsp))
5349 return -EPROTO;
5350
5351 dcid = __le16_to_cpu(rsp->dcid);
5352 mtu = __le16_to_cpu(rsp->mtu);
5353 mps = __le16_to_cpu(rsp->mps);
5354 credits = __le16_to_cpu(rsp->credits);
5355 result = __le16_to_cpu(rsp->result);
5356
5357 if (result == L2CAP_CR_LE_SUCCESS && (mtu < 23 || mps < 23 ||
5358 dcid < L2CAP_CID_DYN_START ||
5359 dcid > L2CAP_CID_LE_DYN_END))
5360 return -EPROTO;
5361
5362 BT_DBG("dcid 0x%4.4x mtu %u mps %u credits %u result 0x%2.2x",
5363 dcid, mtu, mps, credits, result);
5364
5365 mutex_lock(&conn->chan_lock);
5366
5367 chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
5368 if (!chan) {
5369 err = -EBADSLT;
5370 goto unlock;
5371 }
5372
5373 err = 0;
5374
5375 l2cap_chan_lock(chan);
5376
5377 switch (result) {
5378 case L2CAP_CR_LE_SUCCESS:
5379 if (__l2cap_get_chan_by_dcid(conn, dcid)) {
5380 err = -EBADSLT;
5381 break;
5382 }
5383
5384 chan->ident = 0;
5385 chan->dcid = dcid;
5386 chan->omtu = mtu;
5387 chan->remote_mps = mps;
5388 chan->tx_credits = credits;
5389 l2cap_chan_ready(chan);
5390 break;
5391
5392 case L2CAP_CR_LE_AUTHENTICATION:
5393 case L2CAP_CR_LE_ENCRYPTION:
5394 /* If we already have MITM protection we can't do
5395 * anything.
5396 */
5397 if (hcon->sec_level > BT_SECURITY_MEDIUM) {
5398 l2cap_chan_del(chan, ECONNREFUSED);
5399 break;
5400 }
5401
5402 sec_level = hcon->sec_level + 1;
5403 if (chan->sec_level < sec_level)
5404 chan->sec_level = sec_level;
5405
5406 /* We'll need to send a new Connect Request */
5407 clear_bit(FLAG_LE_CONN_REQ_SENT, &chan->flags);
5408
5409 smp_conn_security(hcon, chan->sec_level);
5410 break;
5411
5412 default:
5413 l2cap_chan_del(chan, ECONNREFUSED);
5414 break;
5415 }
5416
5417 l2cap_chan_unlock(chan);
5418
5419 unlock:
5420 mutex_unlock(&conn->chan_lock);
5421
5422 return err;
5423 }
5424
5425 static inline int l2cap_bredr_sig_cmd(struct l2cap_conn *conn,
5426 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5427 u8 *data)
5428 {
5429 int err = 0;
5430
5431 switch (cmd->code) {
5432 case L2CAP_COMMAND_REJ:
5433 l2cap_command_rej(conn, cmd, cmd_len, data);
5434 break;
5435
5436 case L2CAP_CONN_REQ:
5437 err = l2cap_connect_req(conn, cmd, cmd_len, data);
5438 break;
5439
5440 case L2CAP_CONN_RSP:
5441 case L2CAP_CREATE_CHAN_RSP:
5442 l2cap_connect_create_rsp(conn, cmd, cmd_len, data);
5443 break;
5444
5445 case L2CAP_CONF_REQ:
5446 err = l2cap_config_req(conn, cmd, cmd_len, data);
5447 break;
5448
5449 case L2CAP_CONF_RSP:
5450 l2cap_config_rsp(conn, cmd, cmd_len, data);
5451 break;
5452
5453 case L2CAP_DISCONN_REQ:
5454 err = l2cap_disconnect_req(conn, cmd, cmd_len, data);
5455 break;
5456
5457 case L2CAP_DISCONN_RSP:
5458 l2cap_disconnect_rsp(conn, cmd, cmd_len, data);
5459 break;
5460
5461 case L2CAP_ECHO_REQ:
5462 l2cap_send_cmd(conn, cmd->ident, L2CAP_ECHO_RSP, cmd_len, data);
5463 break;
5464
5465 case L2CAP_ECHO_RSP:
5466 break;
5467
5468 case L2CAP_INFO_REQ:
5469 err = l2cap_information_req(conn, cmd, cmd_len, data);
5470 break;
5471
5472 case L2CAP_INFO_RSP:
5473 l2cap_information_rsp(conn, cmd, cmd_len, data);
5474 break;
5475
5476 case L2CAP_CREATE_CHAN_REQ:
5477 err = l2cap_create_channel_req(conn, cmd, cmd_len, data);
5478 break;
5479
5480 case L2CAP_MOVE_CHAN_REQ:
5481 err = l2cap_move_channel_req(conn, cmd, cmd_len, data);
5482 break;
5483
5484 case L2CAP_MOVE_CHAN_RSP:
5485 l2cap_move_channel_rsp(conn, cmd, cmd_len, data);
5486 break;
5487
5488 case L2CAP_MOVE_CHAN_CFM:
5489 err = l2cap_move_channel_confirm(conn, cmd, cmd_len, data);
5490 break;
5491
5492 case L2CAP_MOVE_CHAN_CFM_RSP:
5493 l2cap_move_channel_confirm_rsp(conn, cmd, cmd_len, data);
5494 break;
5495
5496 default:
5497 BT_ERR("Unknown BR/EDR signaling command 0x%2.2x", cmd->code);
5498 err = -EINVAL;
5499 break;
5500 }
5501
5502 return err;
5503 }
5504
5505 static int l2cap_le_connect_req(struct l2cap_conn *conn,
5506 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5507 u8 *data)
5508 {
5509 struct l2cap_le_conn_req *req = (struct l2cap_le_conn_req *) data;
5510 struct l2cap_le_conn_rsp rsp;
5511 struct l2cap_chan *chan, *pchan;
5512 u16 dcid, scid, credits, mtu, mps;
5513 __le16 psm;
5514 u8 result;
5515
5516 if (cmd_len != sizeof(*req))
5517 return -EPROTO;
5518
5519 scid = __le16_to_cpu(req->scid);
5520 mtu = __le16_to_cpu(req->mtu);
5521 mps = __le16_to_cpu(req->mps);
5522 psm = req->psm;
5523 dcid = 0;
5524 credits = 0;
5525
5526 if (mtu < 23 || mps < 23)
5527 return -EPROTO;
5528
5529 BT_DBG("psm 0x%2.2x scid 0x%4.4x mtu %u mps %u", __le16_to_cpu(psm),
5530 scid, mtu, mps);
5531
5532 /* Check if we have socket listening on psm */
5533 pchan = l2cap_global_chan_by_psm(BT_LISTEN, psm, &conn->hcon->src,
5534 &conn->hcon->dst, LE_LINK);
5535 if (!pchan) {
5536 result = L2CAP_CR_LE_BAD_PSM;
5537 chan = NULL;
5538 goto response;
5539 }
5540
5541 mutex_lock(&conn->chan_lock);
5542 l2cap_chan_lock(pchan);
5543
5544 if (!smp_sufficient_security(conn->hcon, pchan->sec_level,
5545 SMP_ALLOW_STK)) {
5546 result = L2CAP_CR_LE_AUTHENTICATION;
5547 chan = NULL;
5548 goto response_unlock;
5549 }
5550
5551 /* Check for valid dynamic CID range */
5552 if (scid < L2CAP_CID_DYN_START || scid > L2CAP_CID_LE_DYN_END) {
5553 result = L2CAP_CR_LE_INVALID_SCID;
5554 chan = NULL;
5555 goto response_unlock;
5556 }
5557
5558 /* Check if we already have channel with that dcid */
5559 if (__l2cap_get_chan_by_dcid(conn, scid)) {
5560 result = L2CAP_CR_LE_SCID_IN_USE;
5561 chan = NULL;
5562 goto response_unlock;
5563 }
5564
5565 chan = pchan->ops->new_connection(pchan);
5566 if (!chan) {
5567 result = L2CAP_CR_LE_NO_MEM;
5568 goto response_unlock;
5569 }
5570
5571 bacpy(&chan->src, &conn->hcon->src);
5572 bacpy(&chan->dst, &conn->hcon->dst);
5573 chan->src_type = bdaddr_src_type(conn->hcon);
5574 chan->dst_type = bdaddr_dst_type(conn->hcon);
5575 chan->psm = psm;
5576 chan->dcid = scid;
5577 chan->omtu = mtu;
5578 chan->remote_mps = mps;
5579
5580 __l2cap_chan_add(conn, chan);
5581
5582 l2cap_le_flowctl_init(chan, __le16_to_cpu(req->credits));
5583
5584 dcid = chan->scid;
5585 credits = chan->rx_credits;
5586
5587 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
5588
5589 chan->ident = cmd->ident;
5590
5591 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
5592 l2cap_state_change(chan, BT_CONNECT2);
5593 /* The following result value is actually not defined
5594 * for LE CoC but we use it to let the function know
5595 * that it should bail out after doing its cleanup
5596 * instead of sending a response.
5597 */
5598 result = L2CAP_CR_PEND;
5599 chan->ops->defer(chan);
5600 } else {
5601 l2cap_chan_ready(chan);
5602 result = L2CAP_CR_LE_SUCCESS;
5603 }
5604
5605 response_unlock:
5606 l2cap_chan_unlock(pchan);
5607 mutex_unlock(&conn->chan_lock);
5608 l2cap_chan_put(pchan);
5609
5610 if (result == L2CAP_CR_PEND)
5611 return 0;
5612
5613 response:
5614 if (chan) {
5615 rsp.mtu = cpu_to_le16(chan->imtu);
5616 rsp.mps = cpu_to_le16(chan->mps);
5617 } else {
5618 rsp.mtu = 0;
5619 rsp.mps = 0;
5620 }
5621
5622 rsp.dcid = cpu_to_le16(dcid);
5623 rsp.credits = cpu_to_le16(credits);
5624 rsp.result = cpu_to_le16(result);
5625
5626 l2cap_send_cmd(conn, cmd->ident, L2CAP_LE_CONN_RSP, sizeof(rsp), &rsp);
5627
5628 return 0;
5629 }
5630
5631 static inline int l2cap_le_credits(struct l2cap_conn *conn,
5632 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5633 u8 *data)
5634 {
5635 struct l2cap_le_credits *pkt;
5636 struct l2cap_chan *chan;
5637 u16 cid, credits, max_credits;
5638
5639 if (cmd_len != sizeof(*pkt))
5640 return -EPROTO;
5641
5642 pkt = (struct l2cap_le_credits *) data;
5643 cid = __le16_to_cpu(pkt->cid);
5644 credits = __le16_to_cpu(pkt->credits);
5645
5646 BT_DBG("cid 0x%4.4x credits 0x%4.4x", cid, credits);
5647
5648 chan = l2cap_get_chan_by_dcid(conn, cid);
5649 if (!chan)
5650 return -EBADSLT;
5651
5652 max_credits = LE_FLOWCTL_MAX_CREDITS - chan->tx_credits;
5653 if (credits > max_credits) {
5654 BT_ERR("LE credits overflow");
5655 l2cap_send_disconn_req(chan, ECONNRESET);
5656 l2cap_chan_unlock(chan);
5657
5658 /* Return 0 so that we don't trigger an unnecessary
5659 * command reject packet.
5660 */
5661 return 0;
5662 }
5663
5664 chan->tx_credits += credits;
5665
5666 /* Resume sending */
5667 l2cap_le_flowctl_send(chan);
5668
5669 if (chan->tx_credits)
5670 chan->ops->resume(chan);
5671
5672 l2cap_chan_unlock(chan);
5673
5674 return 0;
5675 }
5676
5677 static inline int l2cap_le_command_rej(struct l2cap_conn *conn,
5678 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5679 u8 *data)
5680 {
5681 struct l2cap_cmd_rej_unk *rej = (struct l2cap_cmd_rej_unk *) data;
5682 struct l2cap_chan *chan;
5683
5684 if (cmd_len < sizeof(*rej))
5685 return -EPROTO;
5686
5687 mutex_lock(&conn->chan_lock);
5688
5689 chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
5690 if (!chan)
5691 goto done;
5692
5693 l2cap_chan_lock(chan);
5694 l2cap_chan_del(chan, ECONNREFUSED);
5695 l2cap_chan_unlock(chan);
5696
5697 done:
5698 mutex_unlock(&conn->chan_lock);
5699 return 0;
5700 }
5701
5702 static inline int l2cap_le_sig_cmd(struct l2cap_conn *conn,
5703 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5704 u8 *data)
5705 {
5706 int err = 0;
5707
5708 switch (cmd->code) {
5709 case L2CAP_COMMAND_REJ:
5710 l2cap_le_command_rej(conn, cmd, cmd_len, data);
5711 break;
5712
5713 case L2CAP_CONN_PARAM_UPDATE_REQ:
5714 err = l2cap_conn_param_update_req(conn, cmd, cmd_len, data);
5715 break;
5716
5717 case L2CAP_CONN_PARAM_UPDATE_RSP:
5718 break;
5719
5720 case L2CAP_LE_CONN_RSP:
5721 l2cap_le_connect_rsp(conn, cmd, cmd_len, data);
5722 break;
5723
5724 case L2CAP_LE_CONN_REQ:
5725 err = l2cap_le_connect_req(conn, cmd, cmd_len, data);
5726 break;
5727
5728 case L2CAP_LE_CREDITS:
5729 err = l2cap_le_credits(conn, cmd, cmd_len, data);
5730 break;
5731
5732 case L2CAP_DISCONN_REQ:
5733 err = l2cap_disconnect_req(conn, cmd, cmd_len, data);
5734 break;
5735
5736 case L2CAP_DISCONN_RSP:
5737 l2cap_disconnect_rsp(conn, cmd, cmd_len, data);
5738 break;
5739
5740 default:
5741 BT_ERR("Unknown LE signaling command 0x%2.2x", cmd->code);
5742 err = -EINVAL;
5743 break;
5744 }
5745
5746 return err;
5747 }
5748
5749 static inline void l2cap_le_sig_channel(struct l2cap_conn *conn,
5750 struct sk_buff *skb)
5751 {
5752 struct hci_conn *hcon = conn->hcon;
5753 struct l2cap_cmd_hdr *cmd;
5754 u16 len;
5755 int err;
5756
5757 if (hcon->type != LE_LINK)
5758 goto drop;
5759
5760 if (skb->len < L2CAP_CMD_HDR_SIZE)
5761 goto drop;
5762
5763 cmd = (void *) skb->data;
5764 skb_pull(skb, L2CAP_CMD_HDR_SIZE);
5765
5766 len = le16_to_cpu(cmd->len);
5767
5768 BT_DBG("code 0x%2.2x len %d id 0x%2.2x", cmd->code, len, cmd->ident);
5769
5770 if (len != skb->len || !cmd->ident) {
5771 BT_DBG("corrupted command");
5772 goto drop;
5773 }
5774
5775 err = l2cap_le_sig_cmd(conn, cmd, len, skb->data);
5776 if (err) {
5777 struct l2cap_cmd_rej_unk rej;
5778
5779 BT_ERR("Wrong link type (%d)", err);
5780
5781 rej.reason = cpu_to_le16(L2CAP_REJ_NOT_UNDERSTOOD);
5782 l2cap_send_cmd(conn, cmd->ident, L2CAP_COMMAND_REJ,
5783 sizeof(rej), &rej);
5784 }
5785
5786 drop:
5787 kfree_skb(skb);
5788 }
5789
5790 static inline void l2cap_sig_channel(struct l2cap_conn *conn,
5791 struct sk_buff *skb)
5792 {
5793 struct hci_conn *hcon = conn->hcon;
5794 u8 *data = skb->data;
5795 int len = skb->len;
5796 struct l2cap_cmd_hdr cmd;
5797 int err;
5798
5799 l2cap_raw_recv(conn, skb);
5800
5801 if (hcon->type != ACL_LINK)
5802 goto drop;
5803
5804 while (len >= L2CAP_CMD_HDR_SIZE) {
5805 u16 cmd_len;
5806 memcpy(&cmd, data, L2CAP_CMD_HDR_SIZE);
5807 data += L2CAP_CMD_HDR_SIZE;
5808 len -= L2CAP_CMD_HDR_SIZE;
5809
5810 cmd_len = le16_to_cpu(cmd.len);
5811
5812 BT_DBG("code 0x%2.2x len %d id 0x%2.2x", cmd.code, cmd_len,
5813 cmd.ident);
5814
5815 if (cmd_len > len || !cmd.ident) {
5816 BT_DBG("corrupted command");
5817 break;
5818 }
5819
5820 err = l2cap_bredr_sig_cmd(conn, &cmd, cmd_len, data);
5821 if (err) {
5822 struct l2cap_cmd_rej_unk rej;
5823
5824 BT_ERR("Wrong link type (%d)", err);
5825
5826 rej.reason = cpu_to_le16(L2CAP_REJ_NOT_UNDERSTOOD);
5827 l2cap_send_cmd(conn, cmd.ident, L2CAP_COMMAND_REJ,
5828 sizeof(rej), &rej);
5829 }
5830
5831 data += cmd_len;
5832 len -= cmd_len;
5833 }
5834
5835 drop:
5836 kfree_skb(skb);
5837 }
5838
5839 static int l2cap_check_fcs(struct l2cap_chan *chan, struct sk_buff *skb)
5840 {
5841 u16 our_fcs, rcv_fcs;
5842 int hdr_size;
5843
5844 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
5845 hdr_size = L2CAP_EXT_HDR_SIZE;
5846 else
5847 hdr_size = L2CAP_ENH_HDR_SIZE;
5848
5849 if (chan->fcs == L2CAP_FCS_CRC16) {
5850 skb_trim(skb, skb->len - L2CAP_FCS_SIZE);
5851 rcv_fcs = get_unaligned_le16(skb->data + skb->len);
5852 our_fcs = crc16(0, skb->data - hdr_size, skb->len + hdr_size);
5853
5854 if (our_fcs != rcv_fcs)
5855 return -EBADMSG;
5856 }
5857 return 0;
5858 }
5859
5860 static void l2cap_send_i_or_rr_or_rnr(struct l2cap_chan *chan)
5861 {
5862 struct l2cap_ctrl control;
5863
5864 BT_DBG("chan %p", chan);
5865
5866 memset(&control, 0, sizeof(control));
5867 control.sframe = 1;
5868 control.final = 1;
5869 control.reqseq = chan->buffer_seq;
5870 set_bit(CONN_SEND_FBIT, &chan->conn_state);
5871
5872 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
5873 control.super = L2CAP_SUPER_RNR;
5874 l2cap_send_sframe(chan, &control);
5875 }
5876
5877 if (test_and_clear_bit(CONN_REMOTE_BUSY, &chan->conn_state) &&
5878 chan->unacked_frames > 0)
5879 __set_retrans_timer(chan);
5880
5881 /* Send pending iframes */
5882 l2cap_ertm_send(chan);
5883
5884 if (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state) &&
5885 test_bit(CONN_SEND_FBIT, &chan->conn_state)) {
5886 /* F-bit wasn't sent in an s-frame or i-frame yet, so
5887 * send it now.
5888 */
5889 control.super = L2CAP_SUPER_RR;
5890 l2cap_send_sframe(chan, &control);
5891 }
5892 }
5893
5894 static void append_skb_frag(struct sk_buff *skb, struct sk_buff *new_frag,
5895 struct sk_buff **last_frag)
5896 {
5897 /* skb->len reflects data in skb as well as all fragments
5898 * skb->data_len reflects only data in fragments
5899 */
5900 if (!skb_has_frag_list(skb))
5901 skb_shinfo(skb)->frag_list = new_frag;
5902
5903 new_frag->next = NULL;
5904
5905 (*last_frag)->next = new_frag;
5906 *last_frag = new_frag;
5907
5908 skb->len += new_frag->len;
5909 skb->data_len += new_frag->len;
5910 skb->truesize += new_frag->truesize;
5911 }
5912
5913 static int l2cap_reassemble_sdu(struct l2cap_chan *chan, struct sk_buff *skb,
5914 struct l2cap_ctrl *control)
5915 {
5916 int err = -EINVAL;
5917
5918 switch (control->sar) {
5919 case L2CAP_SAR_UNSEGMENTED:
5920 if (chan->sdu)
5921 break;
5922
5923 err = chan->ops->recv(chan, skb);
5924 break;
5925
5926 case L2CAP_SAR_START:
5927 if (chan->sdu)
5928 break;
5929
5930 if (!pskb_may_pull(skb, L2CAP_SDULEN_SIZE))
5931 break;
5932
5933 chan->sdu_len = get_unaligned_le16(skb->data);
5934 skb_pull(skb, L2CAP_SDULEN_SIZE);
5935
5936 if (chan->sdu_len > chan->imtu) {
5937 err = -EMSGSIZE;
5938 break;
5939 }
5940
5941 if (skb->len >= chan->sdu_len)
5942 break;
5943
5944 chan->sdu = skb;
5945 chan->sdu_last_frag = skb;
5946
5947 skb = NULL;
5948 err = 0;
5949 break;
5950
5951 case L2CAP_SAR_CONTINUE:
5952 if (!chan->sdu)
5953 break;
5954
5955 append_skb_frag(chan->sdu, skb,
5956 &chan->sdu_last_frag);
5957 skb = NULL;
5958
5959 if (chan->sdu->len >= chan->sdu_len)
5960 break;
5961
5962 err = 0;
5963 break;
5964
5965 case L2CAP_SAR_END:
5966 if (!chan->sdu)
5967 break;
5968
5969 append_skb_frag(chan->sdu, skb,
5970 &chan->sdu_last_frag);
5971 skb = NULL;
5972
5973 if (chan->sdu->len != chan->sdu_len)
5974 break;
5975
5976 err = chan->ops->recv(chan, chan->sdu);
5977
5978 if (!err) {
5979 /* Reassembly complete */
5980 chan->sdu = NULL;
5981 chan->sdu_last_frag = NULL;
5982 chan->sdu_len = 0;
5983 }
5984 break;
5985 }
5986
5987 if (err) {
5988 kfree_skb(skb);
5989 kfree_skb(chan->sdu);
5990 chan->sdu = NULL;
5991 chan->sdu_last_frag = NULL;
5992 chan->sdu_len = 0;
5993 }
5994
5995 return err;
5996 }
5997
5998 static int l2cap_resegment(struct l2cap_chan *chan)
5999 {
6000 /* Placeholder */
6001 return 0;
6002 }
6003
6004 void l2cap_chan_busy(struct l2cap_chan *chan, int busy)
6005 {
6006 u8 event;
6007
6008 if (chan->mode != L2CAP_MODE_ERTM)
6009 return;
6010
6011 event = busy ? L2CAP_EV_LOCAL_BUSY_DETECTED : L2CAP_EV_LOCAL_BUSY_CLEAR;
6012 l2cap_tx(chan, NULL, NULL, event);
6013 }
6014
6015 static int l2cap_rx_queued_iframes(struct l2cap_chan *chan)
6016 {
6017 int err = 0;
6018 /* Pass sequential frames to l2cap_reassemble_sdu()
6019 * until a gap is encountered.
6020 */
6021
6022 BT_DBG("chan %p", chan);
6023
6024 while (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
6025 struct sk_buff *skb;
6026 BT_DBG("Searching for skb with txseq %d (queue len %d)",
6027 chan->buffer_seq, skb_queue_len(&chan->srej_q));
6028
6029 skb = l2cap_ertm_seq_in_queue(&chan->srej_q, chan->buffer_seq);
6030
6031 if (!skb)
6032 break;
6033
6034 skb_unlink(skb, &chan->srej_q);
6035 chan->buffer_seq = __next_seq(chan, chan->buffer_seq);
6036 err = l2cap_reassemble_sdu(chan, skb, &bt_cb(skb)->l2cap);
6037 if (err)
6038 break;
6039 }
6040
6041 if (skb_queue_empty(&chan->srej_q)) {
6042 chan->rx_state = L2CAP_RX_STATE_RECV;
6043 l2cap_send_ack(chan);
6044 }
6045
6046 return err;
6047 }
6048
6049 static void l2cap_handle_srej(struct l2cap_chan *chan,
6050 struct l2cap_ctrl *control)
6051 {
6052 struct sk_buff *skb;
6053
6054 BT_DBG("chan %p, control %p", chan, control);
6055
6056 if (control->reqseq == chan->next_tx_seq) {
6057 BT_DBG("Invalid reqseq %d, disconnecting", control->reqseq);
6058 l2cap_send_disconn_req(chan, ECONNRESET);
6059 return;
6060 }
6061
6062 skb = l2cap_ertm_seq_in_queue(&chan->tx_q, control->reqseq);
6063
6064 if (skb == NULL) {
6065 BT_DBG("Seq %d not available for retransmission",
6066 control->reqseq);
6067 return;
6068 }
6069
6070 if (chan->max_tx != 0 && bt_cb(skb)->l2cap.retries >= chan->max_tx) {
6071 BT_DBG("Retry limit exceeded (%d)", chan->max_tx);
6072 l2cap_send_disconn_req(chan, ECONNRESET);
6073 return;
6074 }
6075
6076 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6077
6078 if (control->poll) {
6079 l2cap_pass_to_tx(chan, control);
6080
6081 set_bit(CONN_SEND_FBIT, &chan->conn_state);
6082 l2cap_retransmit(chan, control);
6083 l2cap_ertm_send(chan);
6084
6085 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F) {
6086 set_bit(CONN_SREJ_ACT, &chan->conn_state);
6087 chan->srej_save_reqseq = control->reqseq;
6088 }
6089 } else {
6090 l2cap_pass_to_tx_fbit(chan, control);
6091
6092 if (control->final) {
6093 if (chan->srej_save_reqseq != control->reqseq ||
6094 !test_and_clear_bit(CONN_SREJ_ACT,
6095 &chan->conn_state))
6096 l2cap_retransmit(chan, control);
6097 } else {
6098 l2cap_retransmit(chan, control);
6099 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F) {
6100 set_bit(CONN_SREJ_ACT, &chan->conn_state);
6101 chan->srej_save_reqseq = control->reqseq;
6102 }
6103 }
6104 }
6105 }
6106
6107 static void l2cap_handle_rej(struct l2cap_chan *chan,
6108 struct l2cap_ctrl *control)
6109 {
6110 struct sk_buff *skb;
6111
6112 BT_DBG("chan %p, control %p", chan, control);
6113
6114 if (control->reqseq == chan->next_tx_seq) {
6115 BT_DBG("Invalid reqseq %d, disconnecting", control->reqseq);
6116 l2cap_send_disconn_req(chan, ECONNRESET);
6117 return;
6118 }
6119
6120 skb = l2cap_ertm_seq_in_queue(&chan->tx_q, control->reqseq);
6121
6122 if (chan->max_tx && skb &&
6123 bt_cb(skb)->l2cap.retries >= chan->max_tx) {
6124 BT_DBG("Retry limit exceeded (%d)", chan->max_tx);
6125 l2cap_send_disconn_req(chan, ECONNRESET);
6126 return;
6127 }
6128
6129 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6130
6131 l2cap_pass_to_tx(chan, control);
6132
6133 if (control->final) {
6134 if (!test_and_clear_bit(CONN_REJ_ACT, &chan->conn_state))
6135 l2cap_retransmit_all(chan, control);
6136 } else {
6137 l2cap_retransmit_all(chan, control);
6138 l2cap_ertm_send(chan);
6139 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F)
6140 set_bit(CONN_REJ_ACT, &chan->conn_state);
6141 }
6142 }
6143
6144 static u8 l2cap_classify_txseq(struct l2cap_chan *chan, u16 txseq)
6145 {
6146 BT_DBG("chan %p, txseq %d", chan, txseq);
6147
6148 BT_DBG("last_acked_seq %d, expected_tx_seq %d", chan->last_acked_seq,
6149 chan->expected_tx_seq);
6150
6151 if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) {
6152 if (__seq_offset(chan, txseq, chan->last_acked_seq) >=
6153 chan->tx_win) {
6154 /* See notes below regarding "double poll" and
6155 * invalid packets.
6156 */
6157 if (chan->tx_win <= ((chan->tx_win_max + 1) >> 1)) {
6158 BT_DBG("Invalid/Ignore - after SREJ");
6159 return L2CAP_TXSEQ_INVALID_IGNORE;
6160 } else {
6161 BT_DBG("Invalid - in window after SREJ sent");
6162 return L2CAP_TXSEQ_INVALID;
6163 }
6164 }
6165
6166 if (chan->srej_list.head == txseq) {
6167 BT_DBG("Expected SREJ");
6168 return L2CAP_TXSEQ_EXPECTED_SREJ;
6169 }
6170
6171 if (l2cap_ertm_seq_in_queue(&chan->srej_q, txseq)) {
6172 BT_DBG("Duplicate SREJ - txseq already stored");
6173 return L2CAP_TXSEQ_DUPLICATE_SREJ;
6174 }
6175
6176 if (l2cap_seq_list_contains(&chan->srej_list, txseq)) {
6177 BT_DBG("Unexpected SREJ - not requested");
6178 return L2CAP_TXSEQ_UNEXPECTED_SREJ;
6179 }
6180 }
6181
6182 if (chan->expected_tx_seq == txseq) {
6183 if (__seq_offset(chan, txseq, chan->last_acked_seq) >=
6184 chan->tx_win) {
6185 BT_DBG("Invalid - txseq outside tx window");
6186 return L2CAP_TXSEQ_INVALID;
6187 } else {
6188 BT_DBG("Expected");
6189 return L2CAP_TXSEQ_EXPECTED;
6190 }
6191 }
6192
6193 if (__seq_offset(chan, txseq, chan->last_acked_seq) <
6194 __seq_offset(chan, chan->expected_tx_seq, chan->last_acked_seq)) {
6195 BT_DBG("Duplicate - expected_tx_seq later than txseq");
6196 return L2CAP_TXSEQ_DUPLICATE;
6197 }
6198
6199 if (__seq_offset(chan, txseq, chan->last_acked_seq) >= chan->tx_win) {
6200 /* A source of invalid packets is a "double poll" condition,
6201 * where delays cause us to send multiple poll packets. If
6202 * the remote stack receives and processes both polls,
6203 * sequence numbers can wrap around in such a way that a
6204 * resent frame has a sequence number that looks like new data
6205 * with a sequence gap. This would trigger an erroneous SREJ
6206 * request.
6207 *
6208 * Fortunately, this is impossible with a tx window that's
6209 * less than half of the maximum sequence number, which allows
6210 * invalid frames to be safely ignored.
6211 *
6212 * With tx window sizes greater than half of the tx window
6213 * maximum, the frame is invalid and cannot be ignored. This
6214 * causes a disconnect.
6215 */
6216
6217 if (chan->tx_win <= ((chan->tx_win_max + 1) >> 1)) {
6218 BT_DBG("Invalid/Ignore - txseq outside tx window");
6219 return L2CAP_TXSEQ_INVALID_IGNORE;
6220 } else {
6221 BT_DBG("Invalid - txseq outside tx window");
6222 return L2CAP_TXSEQ_INVALID;
6223 }
6224 } else {
6225 BT_DBG("Unexpected - txseq indicates missing frames");
6226 return L2CAP_TXSEQ_UNEXPECTED;
6227 }
6228 }
6229
6230 static int l2cap_rx_state_recv(struct l2cap_chan *chan,
6231 struct l2cap_ctrl *control,
6232 struct sk_buff *skb, u8 event)
6233 {
6234 int err = 0;
6235 bool skb_in_use = false;
6236
6237 BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
6238 event);
6239
6240 switch (event) {
6241 case L2CAP_EV_RECV_IFRAME:
6242 switch (l2cap_classify_txseq(chan, control->txseq)) {
6243 case L2CAP_TXSEQ_EXPECTED:
6244 l2cap_pass_to_tx(chan, control);
6245
6246 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
6247 BT_DBG("Busy, discarding expected seq %d",
6248 control->txseq);
6249 break;
6250 }
6251
6252 chan->expected_tx_seq = __next_seq(chan,
6253 control->txseq);
6254
6255 chan->buffer_seq = chan->expected_tx_seq;
6256 skb_in_use = true;
6257
6258 err = l2cap_reassemble_sdu(chan, skb, control);
6259 if (err)
6260 break;
6261
6262 if (control->final) {
6263 if (!test_and_clear_bit(CONN_REJ_ACT,
6264 &chan->conn_state)) {
6265 control->final = 0;
6266 l2cap_retransmit_all(chan, control);
6267 l2cap_ertm_send(chan);
6268 }
6269 }
6270
6271 if (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state))
6272 l2cap_send_ack(chan);
6273 break;
6274 case L2CAP_TXSEQ_UNEXPECTED:
6275 l2cap_pass_to_tx(chan, control);
6276
6277 /* Can't issue SREJ frames in the local busy state.
6278 * Drop this frame, it will be seen as missing
6279 * when local busy is exited.
6280 */
6281 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
6282 BT_DBG("Busy, discarding unexpected seq %d",
6283 control->txseq);
6284 break;
6285 }
6286
6287 /* There was a gap in the sequence, so an SREJ
6288 * must be sent for each missing frame. The
6289 * current frame is stored for later use.
6290 */
6291 skb_queue_tail(&chan->srej_q, skb);
6292 skb_in_use = true;
6293 BT_DBG("Queued %p (queue len %d)", skb,
6294 skb_queue_len(&chan->srej_q));
6295
6296 clear_bit(CONN_SREJ_ACT, &chan->conn_state);
6297 l2cap_seq_list_clear(&chan->srej_list);
6298 l2cap_send_srej(chan, control->txseq);
6299
6300 chan->rx_state = L2CAP_RX_STATE_SREJ_SENT;
6301 break;
6302 case L2CAP_TXSEQ_DUPLICATE:
6303 l2cap_pass_to_tx(chan, control);
6304 break;
6305 case L2CAP_TXSEQ_INVALID_IGNORE:
6306 break;
6307 case L2CAP_TXSEQ_INVALID:
6308 default:
6309 l2cap_send_disconn_req(chan, ECONNRESET);
6310 break;
6311 }
6312 break;
6313 case L2CAP_EV_RECV_RR:
6314 l2cap_pass_to_tx(chan, control);
6315 if (control->final) {
6316 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6317
6318 if (!test_and_clear_bit(CONN_REJ_ACT, &chan->conn_state) &&
6319 !__chan_is_moving(chan)) {
6320 control->final = 0;
6321 l2cap_retransmit_all(chan, control);
6322 }
6323
6324 l2cap_ertm_send(chan);
6325 } else if (control->poll) {
6326 l2cap_send_i_or_rr_or_rnr(chan);
6327 } else {
6328 if (test_and_clear_bit(CONN_REMOTE_BUSY,
6329 &chan->conn_state) &&
6330 chan->unacked_frames)
6331 __set_retrans_timer(chan);
6332
6333 l2cap_ertm_send(chan);
6334 }
6335 break;
6336 case L2CAP_EV_RECV_RNR:
6337 set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6338 l2cap_pass_to_tx(chan, control);
6339 if (control && control->poll) {
6340 set_bit(CONN_SEND_FBIT, &chan->conn_state);
6341 l2cap_send_rr_or_rnr(chan, 0);
6342 }
6343 __clear_retrans_timer(chan);
6344 l2cap_seq_list_clear(&chan->retrans_list);
6345 break;
6346 case L2CAP_EV_RECV_REJ:
6347 l2cap_handle_rej(chan, control);
6348 break;
6349 case L2CAP_EV_RECV_SREJ:
6350 l2cap_handle_srej(chan, control);
6351 break;
6352 default:
6353 break;
6354 }
6355
6356 if (skb && !skb_in_use) {
6357 BT_DBG("Freeing %p", skb);
6358 kfree_skb(skb);
6359 }
6360
6361 return err;
6362 }
6363
6364 static int l2cap_rx_state_srej_sent(struct l2cap_chan *chan,
6365 struct l2cap_ctrl *control,
6366 struct sk_buff *skb, u8 event)
6367 {
6368 int err = 0;
6369 u16 txseq = control->txseq;
6370 bool skb_in_use = false;
6371
6372 BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
6373 event);
6374
6375 switch (event) {
6376 case L2CAP_EV_RECV_IFRAME:
6377 switch (l2cap_classify_txseq(chan, txseq)) {
6378 case L2CAP_TXSEQ_EXPECTED:
6379 /* Keep frame for reassembly later */
6380 l2cap_pass_to_tx(chan, control);
6381 skb_queue_tail(&chan->srej_q, skb);
6382 skb_in_use = true;
6383 BT_DBG("Queued %p (queue len %d)", skb,
6384 skb_queue_len(&chan->srej_q));
6385
6386 chan->expected_tx_seq = __next_seq(chan, txseq);
6387 break;
6388 case L2CAP_TXSEQ_EXPECTED_SREJ:
6389 l2cap_seq_list_pop(&chan->srej_list);
6390
6391 l2cap_pass_to_tx(chan, control);
6392 skb_queue_tail(&chan->srej_q, skb);
6393 skb_in_use = true;
6394 BT_DBG("Queued %p (queue len %d)", skb,
6395 skb_queue_len(&chan->srej_q));
6396
6397 err = l2cap_rx_queued_iframes(chan);
6398 if (err)
6399 break;
6400
6401 break;
6402 case L2CAP_TXSEQ_UNEXPECTED:
6403 /* Got a frame that can't be reassembled yet.
6404 * Save it for later, and send SREJs to cover
6405 * the missing frames.
6406 */
6407 skb_queue_tail(&chan->srej_q, skb);
6408 skb_in_use = true;
6409 BT_DBG("Queued %p (queue len %d)", skb,
6410 skb_queue_len(&chan->srej_q));
6411
6412 l2cap_pass_to_tx(chan, control);
6413 l2cap_send_srej(chan, control->txseq);
6414 break;
6415 case L2CAP_TXSEQ_UNEXPECTED_SREJ:
6416 /* This frame was requested with an SREJ, but
6417 * some expected retransmitted frames are
6418 * missing. Request retransmission of missing
6419 * SREJ'd frames.
6420 */
6421 skb_queue_tail(&chan->srej_q, skb);
6422 skb_in_use = true;
6423 BT_DBG("Queued %p (queue len %d)", skb,
6424 skb_queue_len(&chan->srej_q));
6425
6426 l2cap_pass_to_tx(chan, control);
6427 l2cap_send_srej_list(chan, control->txseq);
6428 break;
6429 case L2CAP_TXSEQ_DUPLICATE_SREJ:
6430 /* We've already queued this frame. Drop this copy. */
6431 l2cap_pass_to_tx(chan, control);
6432 break;
6433 case L2CAP_TXSEQ_DUPLICATE:
6434 /* Expecting a later sequence number, so this frame
6435 * was already received. Ignore it completely.
6436 */
6437 break;
6438 case L2CAP_TXSEQ_INVALID_IGNORE:
6439 break;
6440 case L2CAP_TXSEQ_INVALID:
6441 default:
6442 l2cap_send_disconn_req(chan, ECONNRESET);
6443 break;
6444 }
6445 break;
6446 case L2CAP_EV_RECV_RR:
6447 l2cap_pass_to_tx(chan, control);
6448 if (control->final) {
6449 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6450
6451 if (!test_and_clear_bit(CONN_REJ_ACT,
6452 &chan->conn_state)) {
6453 control->final = 0;
6454 l2cap_retransmit_all(chan, control);
6455 }
6456
6457 l2cap_ertm_send(chan);
6458 } else if (control->poll) {
6459 if (test_and_clear_bit(CONN_REMOTE_BUSY,
6460 &chan->conn_state) &&
6461 chan->unacked_frames) {
6462 __set_retrans_timer(chan);
6463 }
6464
6465 set_bit(CONN_SEND_FBIT, &chan->conn_state);
6466 l2cap_send_srej_tail(chan);
6467 } else {
6468 if (test_and_clear_bit(CONN_REMOTE_BUSY,
6469 &chan->conn_state) &&
6470 chan->unacked_frames)
6471 __set_retrans_timer(chan);
6472
6473 l2cap_send_ack(chan);
6474 }
6475 break;
6476 case L2CAP_EV_RECV_RNR:
6477 set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6478 l2cap_pass_to_tx(chan, control);
6479 if (control->poll) {
6480 l2cap_send_srej_tail(chan);
6481 } else {
6482 struct l2cap_ctrl rr_control;
6483 memset(&rr_control, 0, sizeof(rr_control));
6484 rr_control.sframe = 1;
6485 rr_control.super = L2CAP_SUPER_RR;
6486 rr_control.reqseq = chan->buffer_seq;
6487 l2cap_send_sframe(chan, &rr_control);
6488 }
6489
6490 break;
6491 case L2CAP_EV_RECV_REJ:
6492 l2cap_handle_rej(chan, control);
6493 break;
6494 case L2CAP_EV_RECV_SREJ:
6495 l2cap_handle_srej(chan, control);
6496 break;
6497 }
6498
6499 if (skb && !skb_in_use) {
6500 BT_DBG("Freeing %p", skb);
6501 kfree_skb(skb);
6502 }
6503
6504 return err;
6505 }
6506
6507 static int l2cap_finish_move(struct l2cap_chan *chan)
6508 {
6509 BT_DBG("chan %p", chan);
6510
6511 chan->rx_state = L2CAP_RX_STATE_RECV;
6512
6513 if (chan->hs_hcon)
6514 chan->conn->mtu = chan->hs_hcon->hdev->block_mtu;
6515 else
6516 chan->conn->mtu = chan->conn->hcon->hdev->acl_mtu;
6517
6518 return l2cap_resegment(chan);
6519 }
6520
6521 static int l2cap_rx_state_wait_p(struct l2cap_chan *chan,
6522 struct l2cap_ctrl *control,
6523 struct sk_buff *skb, u8 event)
6524 {
6525 int err;
6526
6527 BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
6528 event);
6529
6530 if (!control->poll)
6531 return -EPROTO;
6532
6533 l2cap_process_reqseq(chan, control->reqseq);
6534
6535 if (!skb_queue_empty(&chan->tx_q))
6536 chan->tx_send_head = skb_peek(&chan->tx_q);
6537 else
6538 chan->tx_send_head = NULL;
6539
6540 /* Rewind next_tx_seq to the point expected
6541 * by the receiver.
6542 */
6543 chan->next_tx_seq = control->reqseq;
6544 chan->unacked_frames = 0;
6545
6546 err = l2cap_finish_move(chan);
6547 if (err)
6548 return err;
6549
6550 set_bit(CONN_SEND_FBIT, &chan->conn_state);
6551 l2cap_send_i_or_rr_or_rnr(chan);
6552
6553 if (event == L2CAP_EV_RECV_IFRAME)
6554 return -EPROTO;
6555
6556 return l2cap_rx_state_recv(chan, control, NULL, event);
6557 }
6558
6559 static int l2cap_rx_state_wait_f(struct l2cap_chan *chan,
6560 struct l2cap_ctrl *control,
6561 struct sk_buff *skb, u8 event)
6562 {
6563 int err;
6564
6565 if (!control->final)
6566 return -EPROTO;
6567
6568 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6569
6570 chan->rx_state = L2CAP_RX_STATE_RECV;
6571 l2cap_process_reqseq(chan, control->reqseq);
6572
6573 if (!skb_queue_empty(&chan->tx_q))
6574 chan->tx_send_head = skb_peek(&chan->tx_q);
6575 else
6576 chan->tx_send_head = NULL;
6577
6578 /* Rewind next_tx_seq to the point expected
6579 * by the receiver.
6580 */
6581 chan->next_tx_seq = control->reqseq;
6582 chan->unacked_frames = 0;
6583
6584 if (chan->hs_hcon)
6585 chan->conn->mtu = chan->hs_hcon->hdev->block_mtu;
6586 else
6587 chan->conn->mtu = chan->conn->hcon->hdev->acl_mtu;
6588
6589 err = l2cap_resegment(chan);
6590
6591 if (!err)
6592 err = l2cap_rx_state_recv(chan, control, skb, event);
6593
6594 return err;
6595 }
6596
6597 static bool __valid_reqseq(struct l2cap_chan *chan, u16 reqseq)
6598 {
6599 /* Make sure reqseq is for a packet that has been sent but not acked */
6600 u16 unacked;
6601
6602 unacked = __seq_offset(chan, chan->next_tx_seq, chan->expected_ack_seq);
6603 return __seq_offset(chan, chan->next_tx_seq, reqseq) <= unacked;
6604 }
6605
6606 static int l2cap_rx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
6607 struct sk_buff *skb, u8 event)
6608 {
6609 int err = 0;
6610
6611 BT_DBG("chan %p, control %p, skb %p, event %d, state %d", chan,
6612 control, skb, event, chan->rx_state);
6613
6614 if (__valid_reqseq(chan, control->reqseq)) {
6615 switch (chan->rx_state) {
6616 case L2CAP_RX_STATE_RECV:
6617 err = l2cap_rx_state_recv(chan, control, skb, event);
6618 break;
6619 case L2CAP_RX_STATE_SREJ_SENT:
6620 err = l2cap_rx_state_srej_sent(chan, control, skb,
6621 event);
6622 break;
6623 case L2CAP_RX_STATE_WAIT_P:
6624 err = l2cap_rx_state_wait_p(chan, control, skb, event);
6625 break;
6626 case L2CAP_RX_STATE_WAIT_F:
6627 err = l2cap_rx_state_wait_f(chan, control, skb, event);
6628 break;
6629 default:
6630 /* shut it down */
6631 break;
6632 }
6633 } else {
6634 BT_DBG("Invalid reqseq %d (next_tx_seq %d, expected_ack_seq %d",
6635 control->reqseq, chan->next_tx_seq,
6636 chan->expected_ack_seq);
6637 l2cap_send_disconn_req(chan, ECONNRESET);
6638 }
6639
6640 return err;
6641 }
6642
6643 static int l2cap_stream_rx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
6644 struct sk_buff *skb)
6645 {
6646 BT_DBG("chan %p, control %p, skb %p, state %d", chan, control, skb,
6647 chan->rx_state);
6648
6649 if (l2cap_classify_txseq(chan, control->txseq) ==
6650 L2CAP_TXSEQ_EXPECTED) {
6651 l2cap_pass_to_tx(chan, control);
6652
6653 BT_DBG("buffer_seq %d->%d", chan->buffer_seq,
6654 __next_seq(chan, chan->buffer_seq));
6655
6656 chan->buffer_seq = __next_seq(chan, chan->buffer_seq);
6657
6658 l2cap_reassemble_sdu(chan, skb, control);
6659 } else {
6660 if (chan->sdu) {
6661 kfree_skb(chan->sdu);
6662 chan->sdu = NULL;
6663 }
6664 chan->sdu_last_frag = NULL;
6665 chan->sdu_len = 0;
6666
6667 if (skb) {
6668 BT_DBG("Freeing %p", skb);
6669 kfree_skb(skb);
6670 }
6671 }
6672
6673 chan->last_acked_seq = control->txseq;
6674 chan->expected_tx_seq = __next_seq(chan, control->txseq);
6675
6676 return 0;
6677 }
6678
6679 static int l2cap_data_rcv(struct l2cap_chan *chan, struct sk_buff *skb)
6680 {
6681 struct l2cap_ctrl *control = &bt_cb(skb)->l2cap;
6682 u16 len;
6683 u8 event;
6684
6685 __unpack_control(chan, skb);
6686
6687 len = skb->len;
6688
6689 /*
6690 * We can just drop the corrupted I-frame here.
6691 * Receiver will miss it and start proper recovery
6692 * procedures and ask for retransmission.
6693 */
6694 if (l2cap_check_fcs(chan, skb))
6695 goto drop;
6696
6697 if (!control->sframe && control->sar == L2CAP_SAR_START)
6698 len -= L2CAP_SDULEN_SIZE;
6699
6700 if (chan->fcs == L2CAP_FCS_CRC16)
6701 len -= L2CAP_FCS_SIZE;
6702
6703 if (len > chan->mps) {
6704 l2cap_send_disconn_req(chan, ECONNRESET);
6705 goto drop;
6706 }
6707
6708 if ((chan->mode == L2CAP_MODE_ERTM ||
6709 chan->mode == L2CAP_MODE_STREAMING) && sk_filter(chan->data, skb))
6710 goto drop;
6711
6712 if (!control->sframe) {
6713 int err;
6714
6715 BT_DBG("iframe sar %d, reqseq %d, final %d, txseq %d",
6716 control->sar, control->reqseq, control->final,
6717 control->txseq);
6718
6719 /* Validate F-bit - F=0 always valid, F=1 only
6720 * valid in TX WAIT_F
6721 */
6722 if (control->final && chan->tx_state != L2CAP_TX_STATE_WAIT_F)
6723 goto drop;
6724
6725 if (chan->mode != L2CAP_MODE_STREAMING) {
6726 event = L2CAP_EV_RECV_IFRAME;
6727 err = l2cap_rx(chan, control, skb, event);
6728 } else {
6729 err = l2cap_stream_rx(chan, control, skb);
6730 }
6731
6732 if (err)
6733 l2cap_send_disconn_req(chan, ECONNRESET);
6734 } else {
6735 const u8 rx_func_to_event[4] = {
6736 L2CAP_EV_RECV_RR, L2CAP_EV_RECV_REJ,
6737 L2CAP_EV_RECV_RNR, L2CAP_EV_RECV_SREJ
6738 };
6739
6740 /* Only I-frames are expected in streaming mode */
6741 if (chan->mode == L2CAP_MODE_STREAMING)
6742 goto drop;
6743
6744 BT_DBG("sframe reqseq %d, final %d, poll %d, super %d",
6745 control->reqseq, control->final, control->poll,
6746 control->super);
6747
6748 if (len != 0) {
6749 BT_ERR("Trailing bytes: %d in sframe", len);
6750 l2cap_send_disconn_req(chan, ECONNRESET);
6751 goto drop;
6752 }
6753
6754 /* Validate F and P bits */
6755 if (control->final && (control->poll ||
6756 chan->tx_state != L2CAP_TX_STATE_WAIT_F))
6757 goto drop;
6758
6759 event = rx_func_to_event[control->super];
6760 if (l2cap_rx(chan, control, skb, event))
6761 l2cap_send_disconn_req(chan, ECONNRESET);
6762 }
6763
6764 return 0;
6765
6766 drop:
6767 kfree_skb(skb);
6768 return 0;
6769 }
6770
6771 static void l2cap_chan_le_send_credits(struct l2cap_chan *chan)
6772 {
6773 struct l2cap_conn *conn = chan->conn;
6774 struct l2cap_le_credits pkt;
6775 u16 return_credits;
6776
6777 return_credits = ((chan->imtu / chan->mps) + 1) - chan->rx_credits;
6778
6779 if (!return_credits)
6780 return;
6781
6782 BT_DBG("chan %p returning %u credits to sender", chan, return_credits);
6783
6784 chan->rx_credits += return_credits;
6785
6786 pkt.cid = cpu_to_le16(chan->scid);
6787 pkt.credits = cpu_to_le16(return_credits);
6788
6789 chan->ident = l2cap_get_ident(conn);
6790
6791 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CREDITS, sizeof(pkt), &pkt);
6792 }
6793
6794 static int l2cap_le_recv(struct l2cap_chan *chan, struct sk_buff *skb)
6795 {
6796 int err;
6797
6798 BT_DBG("SDU reassemble complete: chan %p skb->len %u", chan, skb->len);
6799
6800 /* Wait recv to confirm reception before updating the credits */
6801 err = chan->ops->recv(chan, skb);
6802
6803 /* Update credits whenever an SDU is received */
6804 l2cap_chan_le_send_credits(chan);
6805
6806 return err;
6807 }
6808
6809 static int l2cap_le_data_rcv(struct l2cap_chan *chan, struct sk_buff *skb)
6810 {
6811 int err;
6812
6813 if (!chan->rx_credits) {
6814 BT_ERR("No credits to receive LE L2CAP data");
6815 l2cap_send_disconn_req(chan, ECONNRESET);
6816 return -ENOBUFS;
6817 }
6818
6819 if (chan->imtu < skb->len) {
6820 BT_ERR("Too big LE L2CAP PDU");
6821 return -ENOBUFS;
6822 }
6823
6824 chan->rx_credits--;
6825 BT_DBG("rx_credits %u -> %u", chan->rx_credits + 1, chan->rx_credits);
6826
6827 /* Update if remote had run out of credits, this should only happens
6828 * if the remote is not using the entire MPS.
6829 */
6830 if (!chan->rx_credits)
6831 l2cap_chan_le_send_credits(chan);
6832
6833 err = 0;
6834
6835 if (!chan->sdu) {
6836 u16 sdu_len;
6837
6838 sdu_len = get_unaligned_le16(skb->data);
6839 skb_pull(skb, L2CAP_SDULEN_SIZE);
6840
6841 BT_DBG("Start of new SDU. sdu_len %u skb->len %u imtu %u",
6842 sdu_len, skb->len, chan->imtu);
6843
6844 if (sdu_len > chan->imtu) {
6845 BT_ERR("Too big LE L2CAP SDU length received");
6846 err = -EMSGSIZE;
6847 goto failed;
6848 }
6849
6850 if (skb->len > sdu_len) {
6851 BT_ERR("Too much LE L2CAP data received");
6852 err = -EINVAL;
6853 goto failed;
6854 }
6855
6856 if (skb->len == sdu_len)
6857 return l2cap_le_recv(chan, skb);
6858
6859 chan->sdu = skb;
6860 chan->sdu_len = sdu_len;
6861 chan->sdu_last_frag = skb;
6862
6863 /* Detect if remote is not able to use the selected MPS */
6864 if (skb->len + L2CAP_SDULEN_SIZE < chan->mps) {
6865 u16 mps_len = skb->len + L2CAP_SDULEN_SIZE;
6866
6867 /* Adjust the number of credits */
6868 BT_DBG("chan->mps %u -> %u", chan->mps, mps_len);
6869 chan->mps = mps_len;
6870 l2cap_chan_le_send_credits(chan);
6871 }
6872
6873 return 0;
6874 }
6875
6876 BT_DBG("SDU fragment. chan->sdu->len %u skb->len %u chan->sdu_len %u",
6877 chan->sdu->len, skb->len, chan->sdu_len);
6878
6879 if (chan->sdu->len + skb->len > chan->sdu_len) {
6880 BT_ERR("Too much LE L2CAP data received");
6881 err = -EINVAL;
6882 goto failed;
6883 }
6884
6885 append_skb_frag(chan->sdu, skb, &chan->sdu_last_frag);
6886 skb = NULL;
6887
6888 if (chan->sdu->len == chan->sdu_len) {
6889 err = l2cap_le_recv(chan, chan->sdu);
6890 if (!err) {
6891 chan->sdu = NULL;
6892 chan->sdu_last_frag = NULL;
6893 chan->sdu_len = 0;
6894 }
6895 }
6896
6897 failed:
6898 if (err) {
6899 kfree_skb(skb);
6900 kfree_skb(chan->sdu);
6901 chan->sdu = NULL;
6902 chan->sdu_last_frag = NULL;
6903 chan->sdu_len = 0;
6904 }
6905
6906 /* We can't return an error here since we took care of the skb
6907 * freeing internally. An error return would cause the caller to
6908 * do a double-free of the skb.
6909 */
6910 return 0;
6911 }
6912
6913 static void l2cap_data_channel(struct l2cap_conn *conn, u16 cid,
6914 struct sk_buff *skb)
6915 {
6916 struct l2cap_chan *chan;
6917
6918 chan = l2cap_get_chan_by_scid(conn, cid);
6919 if (!chan) {
6920 if (cid == L2CAP_CID_A2MP) {
6921 chan = a2mp_channel_create(conn, skb);
6922 if (!chan) {
6923 kfree_skb(skb);
6924 return;
6925 }
6926
6927 l2cap_chan_lock(chan);
6928 } else {
6929 BT_DBG("unknown cid 0x%4.4x", cid);
6930 /* Drop packet and return */
6931 kfree_skb(skb);
6932 return;
6933 }
6934 }
6935
6936 BT_DBG("chan %p, len %d", chan, skb->len);
6937
6938 /* If we receive data on a fixed channel before the info req/rsp
6939 * procdure is done simply assume that the channel is supported
6940 * and mark it as ready.
6941 */
6942 if (chan->chan_type == L2CAP_CHAN_FIXED)
6943 l2cap_chan_ready(chan);
6944
6945 if (chan->state != BT_CONNECTED)
6946 goto drop;
6947
6948 switch (chan->mode) {
6949 case L2CAP_MODE_LE_FLOWCTL:
6950 if (l2cap_le_data_rcv(chan, skb) < 0)
6951 goto drop;
6952
6953 goto done;
6954
6955 case L2CAP_MODE_BASIC:
6956 /* If socket recv buffers overflows we drop data here
6957 * which is *bad* because L2CAP has to be reliable.
6958 * But we don't have any other choice. L2CAP doesn't
6959 * provide flow control mechanism. */
6960
6961 if (chan->imtu < skb->len) {
6962 BT_ERR("Dropping L2CAP data: receive buffer overflow");
6963 goto drop;
6964 }
6965
6966 if (!chan->ops->recv(chan, skb))
6967 goto done;
6968 break;
6969
6970 case L2CAP_MODE_ERTM:
6971 case L2CAP_MODE_STREAMING:
6972 l2cap_data_rcv(chan, skb);
6973 goto done;
6974
6975 default:
6976 BT_DBG("chan %p: bad mode 0x%2.2x", chan, chan->mode);
6977 break;
6978 }
6979
6980 drop:
6981 kfree_skb(skb);
6982
6983 done:
6984 l2cap_chan_unlock(chan);
6985 }
6986
6987 static void l2cap_conless_channel(struct l2cap_conn *conn, __le16 psm,
6988 struct sk_buff *skb)
6989 {
6990 struct hci_conn *hcon = conn->hcon;
6991 struct l2cap_chan *chan;
6992
6993 if (hcon->type != ACL_LINK)
6994 goto free_skb;
6995
6996 chan = l2cap_global_chan_by_psm(0, psm, &hcon->src, &hcon->dst,
6997 ACL_LINK);
6998 if (!chan)
6999 goto free_skb;
7000
7001 BT_DBG("chan %p, len %d", chan, skb->len);
7002
7003 if (chan->state != BT_BOUND && chan->state != BT_CONNECTED)
7004 goto drop;
7005
7006 if (chan->imtu < skb->len)
7007 goto drop;
7008
7009 /* Store remote BD_ADDR and PSM for msg_name */
7010 bacpy(&bt_cb(skb)->l2cap.bdaddr, &hcon->dst);
7011 bt_cb(skb)->l2cap.psm = psm;
7012
7013 if (!chan->ops->recv(chan, skb)) {
7014 l2cap_chan_put(chan);
7015 return;
7016 }
7017
7018 drop:
7019 l2cap_chan_put(chan);
7020 free_skb:
7021 kfree_skb(skb);
7022 }
7023
7024 static void l2cap_recv_frame(struct l2cap_conn *conn, struct sk_buff *skb)
7025 {
7026 struct l2cap_hdr *lh = (void *) skb->data;
7027 struct hci_conn *hcon = conn->hcon;
7028 u16 cid, len;
7029 __le16 psm;
7030
7031 if (hcon->state != BT_CONNECTED) {
7032 BT_DBG("queueing pending rx skb");
7033 skb_queue_tail(&conn->pending_rx, skb);
7034 return;
7035 }
7036
7037 skb_pull(skb, L2CAP_HDR_SIZE);
7038 cid = __le16_to_cpu(lh->cid);
7039 len = __le16_to_cpu(lh->len);
7040
7041 if (len != skb->len) {
7042 kfree_skb(skb);
7043 return;
7044 }
7045
7046 /* Since we can't actively block incoming LE connections we must
7047 * at least ensure that we ignore incoming data from them.
7048 */
7049 if (hcon->type == LE_LINK &&
7050 hci_bdaddr_list_lookup(&hcon->hdev->blacklist, &hcon->dst,
7051 bdaddr_dst_type(hcon))) {
7052 kfree_skb(skb);
7053 return;
7054 }
7055
7056 BT_DBG("len %d, cid 0x%4.4x", len, cid);
7057
7058 switch (cid) {
7059 case L2CAP_CID_SIGNALING:
7060 l2cap_sig_channel(conn, skb);
7061 break;
7062
7063 case L2CAP_CID_CONN_LESS:
7064 psm = get_unaligned((__le16 *) skb->data);
7065 skb_pull(skb, L2CAP_PSMLEN_SIZE);
7066 l2cap_conless_channel(conn, psm, skb);
7067 break;
7068
7069 case L2CAP_CID_LE_SIGNALING:
7070 l2cap_le_sig_channel(conn, skb);
7071 break;
7072
7073 default:
7074 l2cap_data_channel(conn, cid, skb);
7075 break;
7076 }
7077 }
7078
7079 static void process_pending_rx(struct work_struct *work)
7080 {
7081 struct l2cap_conn *conn = container_of(work, struct l2cap_conn,
7082 pending_rx_work);
7083 struct sk_buff *skb;
7084
7085 BT_DBG("");
7086
7087 while ((skb = skb_dequeue(&conn->pending_rx)))
7088 l2cap_recv_frame(conn, skb);
7089 }
7090
7091 static struct l2cap_conn *l2cap_conn_add(struct hci_conn *hcon)
7092 {
7093 struct l2cap_conn *conn = hcon->l2cap_data;
7094 struct hci_chan *hchan;
7095
7096 if (conn)
7097 return conn;
7098
7099 hchan = hci_chan_create(hcon);
7100 if (!hchan)
7101 return NULL;
7102
7103 conn = kzalloc(sizeof(*conn), GFP_KERNEL);
7104 if (!conn) {
7105 hci_chan_del(hchan);
7106 return NULL;
7107 }
7108
7109 kref_init(&conn->ref);
7110 hcon->l2cap_data = conn;
7111 conn->hcon = hci_conn_get(hcon);
7112 conn->hchan = hchan;
7113
7114 BT_DBG("hcon %p conn %p hchan %p", hcon, conn, hchan);
7115
7116 switch (hcon->type) {
7117 case LE_LINK:
7118 if (hcon->hdev->le_mtu) {
7119 conn->mtu = hcon->hdev->le_mtu;
7120 break;
7121 }
7122 /* fall through */
7123 default:
7124 conn->mtu = hcon->hdev->acl_mtu;
7125 break;
7126 }
7127
7128 conn->feat_mask = 0;
7129
7130 conn->local_fixed_chan = L2CAP_FC_SIG_BREDR | L2CAP_FC_CONNLESS;
7131
7132 if (hcon->type == ACL_LINK &&
7133 hci_dev_test_flag(hcon->hdev, HCI_HS_ENABLED))
7134 conn->local_fixed_chan |= L2CAP_FC_A2MP;
7135
7136 if (hci_dev_test_flag(hcon->hdev, HCI_LE_ENABLED) &&
7137 (bredr_sc_enabled(hcon->hdev) ||
7138 hci_dev_test_flag(hcon->hdev, HCI_FORCE_BREDR_SMP)))
7139 conn->local_fixed_chan |= L2CAP_FC_SMP_BREDR;
7140
7141 mutex_init(&conn->ident_lock);
7142 mutex_init(&conn->chan_lock);
7143
7144 INIT_LIST_HEAD(&conn->chan_l);
7145 INIT_LIST_HEAD(&conn->users);
7146
7147 INIT_DELAYED_WORK(&conn->info_timer, l2cap_info_timeout);
7148
7149 skb_queue_head_init(&conn->pending_rx);
7150 INIT_WORK(&conn->pending_rx_work, process_pending_rx);
7151 INIT_WORK(&conn->id_addr_update_work, l2cap_conn_update_id_addr);
7152
7153 conn->disc_reason = HCI_ERROR_REMOTE_USER_TERM;
7154
7155 return conn;
7156 }
7157
7158 static bool is_valid_psm(u16 psm, u8 dst_type) {
7159 if (!psm)
7160 return false;
7161
7162 if (bdaddr_type_is_le(dst_type))
7163 return (psm <= 0x00ff);
7164
7165 /* PSM must be odd and lsb of upper byte must be 0 */
7166 return ((psm & 0x0101) == 0x0001);
7167 }
7168
7169 int l2cap_chan_connect(struct l2cap_chan *chan, __le16 psm, u16 cid,
7170 bdaddr_t *dst, u8 dst_type)
7171 {
7172 struct l2cap_conn *conn;
7173 struct hci_conn *hcon;
7174 struct hci_dev *hdev;
7175 int err;
7176
7177 BT_DBG("%pMR -> %pMR (type %u) psm 0x%2.2x", &chan->src, dst,
7178 dst_type, __le16_to_cpu(psm));
7179
7180 hdev = hci_get_route(dst, &chan->src, chan->src_type);
7181 if (!hdev)
7182 return -EHOSTUNREACH;
7183
7184 hci_dev_lock(hdev);
7185
7186 if (!is_valid_psm(__le16_to_cpu(psm), dst_type) && !cid &&
7187 chan->chan_type != L2CAP_CHAN_RAW) {
7188 err = -EINVAL;
7189 goto done;
7190 }
7191
7192 if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED && !psm) {
7193 err = -EINVAL;
7194 goto done;
7195 }
7196
7197 if (chan->chan_type == L2CAP_CHAN_FIXED && !cid) {
7198 err = -EINVAL;
7199 goto done;
7200 }
7201
7202 switch (chan->mode) {
7203 case L2CAP_MODE_BASIC:
7204 break;
7205 case L2CAP_MODE_LE_FLOWCTL:
7206 break;
7207 case L2CAP_MODE_ERTM:
7208 case L2CAP_MODE_STREAMING:
7209 if (!disable_ertm)
7210 break;
7211 /* fall through */
7212 default:
7213 err = -EOPNOTSUPP;
7214 goto done;
7215 }
7216
7217 switch (chan->state) {
7218 case BT_CONNECT:
7219 case BT_CONNECT2:
7220 case BT_CONFIG:
7221 /* Already connecting */
7222 err = 0;
7223 goto done;
7224
7225 case BT_CONNECTED:
7226 /* Already connected */
7227 err = -EISCONN;
7228 goto done;
7229
7230 case BT_OPEN:
7231 case BT_BOUND:
7232 /* Can connect */
7233 break;
7234
7235 default:
7236 err = -EBADFD;
7237 goto done;
7238 }
7239
7240 /* Set destination address and psm */
7241 bacpy(&chan->dst, dst);
7242 chan->dst_type = dst_type;
7243
7244 chan->psm = psm;
7245 chan->dcid = cid;
7246
7247 if (bdaddr_type_is_le(dst_type)) {
7248 /* Convert from L2CAP channel address type to HCI address type
7249 */
7250 if (dst_type == BDADDR_LE_PUBLIC)
7251 dst_type = ADDR_LE_DEV_PUBLIC;
7252 else
7253 dst_type = ADDR_LE_DEV_RANDOM;
7254
7255 if (hci_dev_test_flag(hdev, HCI_ADVERTISING))
7256 hcon = hci_connect_le(hdev, dst, dst_type,
7257 chan->sec_level,
7258 HCI_LE_CONN_TIMEOUT,
7259 HCI_ROLE_SLAVE, NULL);
7260 else
7261 hcon = hci_connect_le_scan(hdev, dst, dst_type,
7262 chan->sec_level,
7263 HCI_LE_CONN_TIMEOUT);
7264
7265 } else {
7266 u8 auth_type = l2cap_get_auth_type(chan);
7267 hcon = hci_connect_acl(hdev, dst, chan->sec_level, auth_type);
7268 }
7269
7270 if (IS_ERR(hcon)) {
7271 err = PTR_ERR(hcon);
7272 goto done;
7273 }
7274
7275 conn = l2cap_conn_add(hcon);
7276 if (!conn) {
7277 hci_conn_drop(hcon);
7278 err = -ENOMEM;
7279 goto done;
7280 }
7281
7282 mutex_lock(&conn->chan_lock);
7283 l2cap_chan_lock(chan);
7284
7285 if (cid && __l2cap_get_chan_by_dcid(conn, cid)) {
7286 hci_conn_drop(hcon);
7287 err = -EBUSY;
7288 goto chan_unlock;
7289 }
7290
7291 /* Update source addr of the socket */
7292 bacpy(&chan->src, &hcon->src);
7293 chan->src_type = bdaddr_src_type(hcon);
7294
7295 __l2cap_chan_add(conn, chan);
7296
7297 /* l2cap_chan_add takes its own ref so we can drop this one */
7298 hci_conn_drop(hcon);
7299
7300 l2cap_state_change(chan, BT_CONNECT);
7301 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
7302
7303 /* Release chan->sport so that it can be reused by other
7304 * sockets (as it's only used for listening sockets).
7305 */
7306 write_lock(&chan_list_lock);
7307 chan->sport = 0;
7308 write_unlock(&chan_list_lock);
7309
7310 if (hcon->state == BT_CONNECTED) {
7311 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
7312 __clear_chan_timer(chan);
7313 if (l2cap_chan_check_security(chan, true))
7314 l2cap_state_change(chan, BT_CONNECTED);
7315 } else
7316 l2cap_do_start(chan);
7317 }
7318
7319 err = 0;
7320
7321 chan_unlock:
7322 l2cap_chan_unlock(chan);
7323 mutex_unlock(&conn->chan_lock);
7324 done:
7325 hci_dev_unlock(hdev);
7326 hci_dev_put(hdev);
7327 return err;
7328 }
7329 EXPORT_SYMBOL_GPL(l2cap_chan_connect);
7330
7331 /* ---- L2CAP interface with lower layer (HCI) ---- */
7332
7333 int l2cap_connect_ind(struct hci_dev *hdev, bdaddr_t *bdaddr)
7334 {
7335 int exact = 0, lm1 = 0, lm2 = 0;
7336 struct l2cap_chan *c;
7337
7338 BT_DBG("hdev %s, bdaddr %pMR", hdev->name, bdaddr);
7339
7340 /* Find listening sockets and check their link_mode */
7341 read_lock(&chan_list_lock);
7342 list_for_each_entry(c, &chan_list, global_l) {
7343 if (c->state != BT_LISTEN)
7344 continue;
7345
7346 if (!bacmp(&c->src, &hdev->bdaddr)) {
7347 lm1 |= HCI_LM_ACCEPT;
7348 if (test_bit(FLAG_ROLE_SWITCH, &c->flags))
7349 lm1 |= HCI_LM_MASTER;
7350 exact++;
7351 } else if (!bacmp(&c->src, BDADDR_ANY)) {
7352 lm2 |= HCI_LM_ACCEPT;
7353 if (test_bit(FLAG_ROLE_SWITCH, &c->flags))
7354 lm2 |= HCI_LM_MASTER;
7355 }
7356 }
7357 read_unlock(&chan_list_lock);
7358
7359 return exact ? lm1 : lm2;
7360 }
7361
7362 /* Find the next fixed channel in BT_LISTEN state, continue iteration
7363 * from an existing channel in the list or from the beginning of the
7364 * global list (by passing NULL as first parameter).
7365 */
7366 static struct l2cap_chan *l2cap_global_fixed_chan(struct l2cap_chan *c,
7367 struct hci_conn *hcon)
7368 {
7369 u8 src_type = bdaddr_src_type(hcon);
7370
7371 read_lock(&chan_list_lock);
7372
7373 if (c)
7374 c = list_next_entry(c, global_l);
7375 else
7376 c = list_entry(chan_list.next, typeof(*c), global_l);
7377
7378 list_for_each_entry_from(c, &chan_list, global_l) {
7379 if (c->chan_type != L2CAP_CHAN_FIXED)
7380 continue;
7381 if (c->state != BT_LISTEN)
7382 continue;
7383 if (bacmp(&c->src, &hcon->src) && bacmp(&c->src, BDADDR_ANY))
7384 continue;
7385 if (src_type != c->src_type)
7386 continue;
7387
7388 l2cap_chan_hold(c);
7389 read_unlock(&chan_list_lock);
7390 return c;
7391 }
7392
7393 read_unlock(&chan_list_lock);
7394
7395 return NULL;
7396 }
7397
7398 static void l2cap_connect_cfm(struct hci_conn *hcon, u8 status)
7399 {
7400 struct hci_dev *hdev = hcon->hdev;
7401 struct l2cap_conn *conn;
7402 struct l2cap_chan *pchan;
7403 u8 dst_type;
7404
7405 if (hcon->type != ACL_LINK && hcon->type != LE_LINK)
7406 return;
7407
7408 BT_DBG("hcon %p bdaddr %pMR status %d", hcon, &hcon->dst, status);
7409
7410 if (status) {
7411 l2cap_conn_del(hcon, bt_to_errno(status));
7412 return;
7413 }
7414
7415 conn = l2cap_conn_add(hcon);
7416 if (!conn)
7417 return;
7418
7419 dst_type = bdaddr_dst_type(hcon);
7420
7421 /* If device is blocked, do not create channels for it */
7422 if (hci_bdaddr_list_lookup(&hdev->blacklist, &hcon->dst, dst_type))
7423 return;
7424
7425 /* Find fixed channels and notify them of the new connection. We
7426 * use multiple individual lookups, continuing each time where
7427 * we left off, because the list lock would prevent calling the
7428 * potentially sleeping l2cap_chan_lock() function.
7429 */
7430 pchan = l2cap_global_fixed_chan(NULL, hcon);
7431 while (pchan) {
7432 struct l2cap_chan *chan, *next;
7433
7434 /* Client fixed channels should override server ones */
7435 if (__l2cap_get_chan_by_dcid(conn, pchan->scid))
7436 goto next;
7437
7438 l2cap_chan_lock(pchan);
7439 chan = pchan->ops->new_connection(pchan);
7440 if (chan) {
7441 bacpy(&chan->src, &hcon->src);
7442 bacpy(&chan->dst, &hcon->dst);
7443 chan->src_type = bdaddr_src_type(hcon);
7444 chan->dst_type = dst_type;
7445
7446 __l2cap_chan_add(conn, chan);
7447 }
7448
7449 l2cap_chan_unlock(pchan);
7450 next:
7451 next = l2cap_global_fixed_chan(pchan, hcon);
7452 l2cap_chan_put(pchan);
7453 pchan = next;
7454 }
7455
7456 l2cap_conn_ready(conn);
7457 }
7458
7459 int l2cap_disconn_ind(struct hci_conn *hcon)
7460 {
7461 struct l2cap_conn *conn = hcon->l2cap_data;
7462
7463 BT_DBG("hcon %p", hcon);
7464
7465 if (!conn)
7466 return HCI_ERROR_REMOTE_USER_TERM;
7467 return conn->disc_reason;
7468 }
7469
7470 static void l2cap_disconn_cfm(struct hci_conn *hcon, u8 reason)
7471 {
7472 if (hcon->type != ACL_LINK && hcon->type != LE_LINK)
7473 return;
7474
7475 BT_DBG("hcon %p reason %d", hcon, reason);
7476
7477 l2cap_conn_del(hcon, bt_to_errno(reason));
7478 }
7479
7480 static inline void l2cap_check_encryption(struct l2cap_chan *chan, u8 encrypt)
7481 {
7482 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED)
7483 return;
7484
7485 if (encrypt == 0x00) {
7486 if (chan->sec_level == BT_SECURITY_MEDIUM) {
7487 __set_chan_timer(chan, L2CAP_ENC_TIMEOUT);
7488 } else if (chan->sec_level == BT_SECURITY_HIGH ||
7489 chan->sec_level == BT_SECURITY_FIPS)
7490 l2cap_chan_close(chan, ECONNREFUSED);
7491 } else {
7492 if (chan->sec_level == BT_SECURITY_MEDIUM)
7493 __clear_chan_timer(chan);
7494 }
7495 }
7496
7497 static void l2cap_security_cfm(struct hci_conn *hcon, u8 status, u8 encrypt)
7498 {
7499 struct l2cap_conn *conn = hcon->l2cap_data;
7500 struct l2cap_chan *chan;
7501
7502 if (!conn)
7503 return;
7504
7505 BT_DBG("conn %p status 0x%2.2x encrypt %u", conn, status, encrypt);
7506
7507 mutex_lock(&conn->chan_lock);
7508
7509 list_for_each_entry(chan, &conn->chan_l, list) {
7510 l2cap_chan_lock(chan);
7511
7512 BT_DBG("chan %p scid 0x%4.4x state %s", chan, chan->scid,
7513 state_to_string(chan->state));
7514
7515 if (chan->scid == L2CAP_CID_A2MP) {
7516 l2cap_chan_unlock(chan);
7517 continue;
7518 }
7519
7520 if (!status && encrypt)
7521 chan->sec_level = hcon->sec_level;
7522
7523 if (!__l2cap_no_conn_pending(chan)) {
7524 l2cap_chan_unlock(chan);
7525 continue;
7526 }
7527
7528 if (!status && (chan->state == BT_CONNECTED ||
7529 chan->state == BT_CONFIG)) {
7530 chan->ops->resume(chan);
7531 l2cap_check_encryption(chan, encrypt);
7532 l2cap_chan_unlock(chan);
7533 continue;
7534 }
7535
7536 if (chan->state == BT_CONNECT) {
7537 if (!status && l2cap_check_enc_key_size(hcon))
7538 l2cap_start_connection(chan);
7539 else
7540 __set_chan_timer(chan, L2CAP_DISC_TIMEOUT);
7541 } else if (chan->state == BT_CONNECT2 &&
7542 chan->mode != L2CAP_MODE_LE_FLOWCTL) {
7543 struct l2cap_conn_rsp rsp;
7544 __u16 res, stat;
7545
7546 if (!status && l2cap_check_enc_key_size(hcon)) {
7547 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
7548 res = L2CAP_CR_PEND;
7549 stat = L2CAP_CS_AUTHOR_PEND;
7550 chan->ops->defer(chan);
7551 } else {
7552 l2cap_state_change(chan, BT_CONFIG);
7553 res = L2CAP_CR_SUCCESS;
7554 stat = L2CAP_CS_NO_INFO;
7555 }
7556 } else {
7557 l2cap_state_change(chan, BT_DISCONN);
7558 __set_chan_timer(chan, L2CAP_DISC_TIMEOUT);
7559 res = L2CAP_CR_SEC_BLOCK;
7560 stat = L2CAP_CS_NO_INFO;
7561 }
7562
7563 rsp.scid = cpu_to_le16(chan->dcid);
7564 rsp.dcid = cpu_to_le16(chan->scid);
7565 rsp.result = cpu_to_le16(res);
7566 rsp.status = cpu_to_le16(stat);
7567 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP,
7568 sizeof(rsp), &rsp);
7569
7570 if (!test_bit(CONF_REQ_SENT, &chan->conf_state) &&
7571 res == L2CAP_CR_SUCCESS) {
7572 char buf[128];
7573 set_bit(CONF_REQ_SENT, &chan->conf_state);
7574 l2cap_send_cmd(conn, l2cap_get_ident(conn),
7575 L2CAP_CONF_REQ,
7576 l2cap_build_conf_req(chan, buf, sizeof(buf)),
7577 buf);
7578 chan->num_conf_req++;
7579 }
7580 }
7581
7582 l2cap_chan_unlock(chan);
7583 }
7584
7585 mutex_unlock(&conn->chan_lock);
7586 }
7587
7588 void l2cap_recv_acldata(struct hci_conn *hcon, struct sk_buff *skb, u16 flags)
7589 {
7590 struct l2cap_conn *conn = hcon->l2cap_data;
7591 struct l2cap_hdr *hdr;
7592 int len;
7593
7594 /* For AMP controller do not create l2cap conn */
7595 if (!conn && hcon->hdev->dev_type != HCI_PRIMARY)
7596 goto drop;
7597
7598 if (!conn)
7599 conn = l2cap_conn_add(hcon);
7600
7601 if (!conn)
7602 goto drop;
7603
7604 BT_DBG("conn %p len %d flags 0x%x", conn, skb->len, flags);
7605
7606 switch (flags) {
7607 case ACL_START:
7608 case ACL_START_NO_FLUSH:
7609 case ACL_COMPLETE:
7610 if (conn->rx_len) {
7611 BT_ERR("Unexpected start frame (len %d)", skb->len);
7612 kfree_skb(conn->rx_skb);
7613 conn->rx_skb = NULL;
7614 conn->rx_len = 0;
7615 l2cap_conn_unreliable(conn, ECOMM);
7616 }
7617
7618 /* Start fragment always begin with Basic L2CAP header */
7619 if (skb->len < L2CAP_HDR_SIZE) {
7620 BT_ERR("Frame is too short (len %d)", skb->len);
7621 l2cap_conn_unreliable(conn, ECOMM);
7622 goto drop;
7623 }
7624
7625 hdr = (struct l2cap_hdr *) skb->data;
7626 len = __le16_to_cpu(hdr->len) + L2CAP_HDR_SIZE;
7627
7628 if (len == skb->len) {
7629 /* Complete frame received */
7630 l2cap_recv_frame(conn, skb);
7631 return;
7632 }
7633
7634 BT_DBG("Start: total len %d, frag len %d", len, skb->len);
7635
7636 if (skb->len > len) {
7637 BT_ERR("Frame is too long (len %d, expected len %d)",
7638 skb->len, len);
7639 l2cap_conn_unreliable(conn, ECOMM);
7640 goto drop;
7641 }
7642
7643 /* Allocate skb for the complete frame (with header) */
7644 conn->rx_skb = bt_skb_alloc(len, GFP_KERNEL);
7645 if (!conn->rx_skb)
7646 goto drop;
7647
7648 skb_copy_from_linear_data(skb, skb_put(conn->rx_skb, skb->len),
7649 skb->len);
7650 conn->rx_len = len - skb->len;
7651 break;
7652
7653 case ACL_CONT:
7654 BT_DBG("Cont: frag len %d (expecting %d)", skb->len, conn->rx_len);
7655
7656 if (!conn->rx_len) {
7657 BT_ERR("Unexpected continuation frame (len %d)", skb->len);
7658 l2cap_conn_unreliable(conn, ECOMM);
7659 goto drop;
7660 }
7661
7662 if (skb->len > conn->rx_len) {
7663 BT_ERR("Fragment is too long (len %d, expected %d)",
7664 skb->len, conn->rx_len);
7665 kfree_skb(conn->rx_skb);
7666 conn->rx_skb = NULL;
7667 conn->rx_len = 0;
7668 l2cap_conn_unreliable(conn, ECOMM);
7669 goto drop;
7670 }
7671
7672 skb_copy_from_linear_data(skb, skb_put(conn->rx_skb, skb->len),
7673 skb->len);
7674 conn->rx_len -= skb->len;
7675
7676 if (!conn->rx_len) {
7677 /* Complete frame received. l2cap_recv_frame
7678 * takes ownership of the skb so set the global
7679 * rx_skb pointer to NULL first.
7680 */
7681 struct sk_buff *rx_skb = conn->rx_skb;
7682 conn->rx_skb = NULL;
7683 l2cap_recv_frame(conn, rx_skb);
7684 }
7685 break;
7686 }
7687
7688 drop:
7689 kfree_skb(skb);
7690 }
7691
7692 static struct hci_cb l2cap_cb = {
7693 .name = "L2CAP",
7694 .connect_cfm = l2cap_connect_cfm,
7695 .disconn_cfm = l2cap_disconn_cfm,
7696 .security_cfm = l2cap_security_cfm,
7697 };
7698
7699 static int l2cap_debugfs_show(struct seq_file *f, void *p)
7700 {
7701 struct l2cap_chan *c;
7702
7703 read_lock(&chan_list_lock);
7704
7705 list_for_each_entry(c, &chan_list, global_l) {
7706 seq_printf(f, "%pMR (%u) %pMR (%u) %d %d 0x%4.4x 0x%4.4x %d %d %d %d\n",
7707 &c->src, c->src_type, &c->dst, c->dst_type,
7708 c->state, __le16_to_cpu(c->psm),
7709 c->scid, c->dcid, c->imtu, c->omtu,
7710 c->sec_level, c->mode);
7711 }
7712
7713 read_unlock(&chan_list_lock);
7714
7715 return 0;
7716 }
7717
7718 DEFINE_SHOW_ATTRIBUTE(l2cap_debugfs);
7719
7720 static struct dentry *l2cap_debugfs;
7721
7722 int __init l2cap_init(void)
7723 {
7724 int err;
7725
7726 err = l2cap_init_sockets();
7727 if (err < 0)
7728 return err;
7729
7730 hci_register_cb(&l2cap_cb);
7731
7732 if (IS_ERR_OR_NULL(bt_debugfs))
7733 return 0;
7734
7735 l2cap_debugfs = debugfs_create_file("l2cap", 0444, bt_debugfs,
7736 NULL, &l2cap_debugfs_fops);
7737
7738 return 0;
7739 }
7740
7741 void l2cap_exit(void)
7742 {
7743 debugfs_remove(l2cap_debugfs);
7744 hci_unregister_cb(&l2cap_cb);
7745 l2cap_cleanup_sockets();
7746 }
7747
7748 module_param(disable_ertm, bool, 0644);
7749 MODULE_PARM_DESC(disable_ertm, "Disable enhanced retransmission mode");
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