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[deliverable/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
36 #include <net/bluetooth/bluetooth.h>
37 #include <net/bluetooth/hci_core.h>
38 #include <net/bluetooth/l2cap.h>
39
40 #include "smp.h"
41 #include "a2mp.h"
42 #include "amp.h"
43
44 #define LE_FLOWCTL_MAX_CREDITS 65535
45
46 bool disable_ertm;
47
48 static u32 l2cap_feat_mask = L2CAP_FEAT_FIXED_CHAN | L2CAP_FEAT_UCD;
49
50 static LIST_HEAD(chan_list);
51 static DEFINE_RWLOCK(chan_list_lock);
52
53 static u16 le_max_credits = L2CAP_LE_MAX_CREDITS;
54 static u16 le_default_mps = L2CAP_LE_DEFAULT_MPS;
55
56 static struct sk_buff *l2cap_build_cmd(struct l2cap_conn *conn,
57 u8 code, u8 ident, u16 dlen, void *data);
58 static void l2cap_send_cmd(struct l2cap_conn *conn, u8 ident, u8 code, u16 len,
59 void *data);
60 static int l2cap_build_conf_req(struct l2cap_chan *chan, void *data);
61 static void l2cap_send_disconn_req(struct l2cap_chan *chan, int err);
62
63 static void l2cap_tx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
64 struct sk_buff_head *skbs, u8 event);
65
66 static inline u8 bdaddr_type(u8 link_type, u8 bdaddr_type)
67 {
68 if (link_type == LE_LINK) {
69 if (bdaddr_type == ADDR_LE_DEV_PUBLIC)
70 return BDADDR_LE_PUBLIC;
71 else
72 return BDADDR_LE_RANDOM;
73 }
74
75 return BDADDR_BREDR;
76 }
77
78 static inline u8 bdaddr_src_type(struct hci_conn *hcon)
79 {
80 return bdaddr_type(hcon->type, hcon->src_type);
81 }
82
83 static inline u8 bdaddr_dst_type(struct hci_conn *hcon)
84 {
85 return bdaddr_type(hcon->type, hcon->dst_type);
86 }
87
88 /* ---- L2CAP channels ---- */
89
90 static struct l2cap_chan *__l2cap_get_chan_by_dcid(struct l2cap_conn *conn,
91 u16 cid)
92 {
93 struct l2cap_chan *c;
94
95 list_for_each_entry(c, &conn->chan_l, list) {
96 if (c->dcid == cid)
97 return c;
98 }
99 return NULL;
100 }
101
102 static struct l2cap_chan *__l2cap_get_chan_by_scid(struct l2cap_conn *conn,
103 u16 cid)
104 {
105 struct l2cap_chan *c;
106
107 list_for_each_entry(c, &conn->chan_l, list) {
108 if (c->scid == cid)
109 return c;
110 }
111 return NULL;
112 }
113
114 /* Find channel with given SCID.
115 * Returns locked channel. */
116 static struct l2cap_chan *l2cap_get_chan_by_scid(struct l2cap_conn *conn,
117 u16 cid)
118 {
119 struct l2cap_chan *c;
120
121 mutex_lock(&conn->chan_lock);
122 c = __l2cap_get_chan_by_scid(conn, cid);
123 if (c)
124 l2cap_chan_lock(c);
125 mutex_unlock(&conn->chan_lock);
126
127 return c;
128 }
129
130 /* Find channel with given DCID.
131 * Returns locked channel.
132 */
133 static struct l2cap_chan *l2cap_get_chan_by_dcid(struct l2cap_conn *conn,
134 u16 cid)
135 {
136 struct l2cap_chan *c;
137
138 mutex_lock(&conn->chan_lock);
139 c = __l2cap_get_chan_by_dcid(conn, cid);
140 if (c)
141 l2cap_chan_lock(c);
142 mutex_unlock(&conn->chan_lock);
143
144 return c;
145 }
146
147 static struct l2cap_chan *__l2cap_get_chan_by_ident(struct l2cap_conn *conn,
148 u8 ident)
149 {
150 struct l2cap_chan *c;
151
152 list_for_each_entry(c, &conn->chan_l, list) {
153 if (c->ident == ident)
154 return c;
155 }
156 return NULL;
157 }
158
159 static struct l2cap_chan *l2cap_get_chan_by_ident(struct l2cap_conn *conn,
160 u8 ident)
161 {
162 struct l2cap_chan *c;
163
164 mutex_lock(&conn->chan_lock);
165 c = __l2cap_get_chan_by_ident(conn, ident);
166 if (c)
167 l2cap_chan_lock(c);
168 mutex_unlock(&conn->chan_lock);
169
170 return c;
171 }
172
173 static struct l2cap_chan *__l2cap_global_chan_by_addr(__le16 psm, bdaddr_t *src)
174 {
175 struct l2cap_chan *c;
176
177 list_for_each_entry(c, &chan_list, global_l) {
178 if (c->sport == psm && !bacmp(&c->src, src))
179 return c;
180 }
181 return NULL;
182 }
183
184 int l2cap_add_psm(struct l2cap_chan *chan, bdaddr_t *src, __le16 psm)
185 {
186 int err;
187
188 write_lock(&chan_list_lock);
189
190 if (psm && __l2cap_global_chan_by_addr(psm, src)) {
191 err = -EADDRINUSE;
192 goto done;
193 }
194
195 if (psm) {
196 chan->psm = psm;
197 chan->sport = psm;
198 err = 0;
199 } else {
200 u16 p, start, end, incr;
201
202 if (chan->src_type == BDADDR_BREDR) {
203 start = L2CAP_PSM_DYN_START;
204 end = L2CAP_PSM_AUTO_END;
205 incr = 2;
206 } else {
207 start = L2CAP_PSM_LE_DYN_START;
208 end = L2CAP_PSM_LE_DYN_END;
209 incr = 1;
210 }
211
212 err = -EINVAL;
213 for (p = start; p <= end; p += incr)
214 if (!__l2cap_global_chan_by_addr(cpu_to_le16(p), src)) {
215 chan->psm = cpu_to_le16(p);
216 chan->sport = cpu_to_le16(p);
217 err = 0;
218 break;
219 }
220 }
221
222 done:
223 write_unlock(&chan_list_lock);
224 return err;
225 }
226 EXPORT_SYMBOL_GPL(l2cap_add_psm);
227
228 int l2cap_add_scid(struct l2cap_chan *chan, __u16 scid)
229 {
230 write_lock(&chan_list_lock);
231
232 /* Override the defaults (which are for conn-oriented) */
233 chan->omtu = L2CAP_DEFAULT_MTU;
234 chan->chan_type = L2CAP_CHAN_FIXED;
235
236 chan->scid = scid;
237
238 write_unlock(&chan_list_lock);
239
240 return 0;
241 }
242
243 static u16 l2cap_alloc_cid(struct l2cap_conn *conn)
244 {
245 u16 cid, dyn_end;
246
247 if (conn->hcon->type == LE_LINK)
248 dyn_end = L2CAP_CID_LE_DYN_END;
249 else
250 dyn_end = L2CAP_CID_DYN_END;
251
252 for (cid = L2CAP_CID_DYN_START; cid <= dyn_end; cid++) {
253 if (!__l2cap_get_chan_by_scid(conn, cid))
254 return cid;
255 }
256
257 return 0;
258 }
259
260 static void l2cap_state_change(struct l2cap_chan *chan, int state)
261 {
262 BT_DBG("chan %p %s -> %s", chan, state_to_string(chan->state),
263 state_to_string(state));
264
265 chan->state = state;
266 chan->ops->state_change(chan, state, 0);
267 }
268
269 static inline void l2cap_state_change_and_error(struct l2cap_chan *chan,
270 int state, int err)
271 {
272 chan->state = state;
273 chan->ops->state_change(chan, chan->state, err);
274 }
275
276 static inline void l2cap_chan_set_err(struct l2cap_chan *chan, int err)
277 {
278 chan->ops->state_change(chan, chan->state, err);
279 }
280
281 static void __set_retrans_timer(struct l2cap_chan *chan)
282 {
283 if (!delayed_work_pending(&chan->monitor_timer) &&
284 chan->retrans_timeout) {
285 l2cap_set_timer(chan, &chan->retrans_timer,
286 msecs_to_jiffies(chan->retrans_timeout));
287 }
288 }
289
290 static void __set_monitor_timer(struct l2cap_chan *chan)
291 {
292 __clear_retrans_timer(chan);
293 if (chan->monitor_timeout) {
294 l2cap_set_timer(chan, &chan->monitor_timer,
295 msecs_to_jiffies(chan->monitor_timeout));
296 }
297 }
298
299 static struct sk_buff *l2cap_ertm_seq_in_queue(struct sk_buff_head *head,
300 u16 seq)
301 {
302 struct sk_buff *skb;
303
304 skb_queue_walk(head, skb) {
305 if (bt_cb(skb)->l2cap.txseq == seq)
306 return skb;
307 }
308
309 return NULL;
310 }
311
312 /* ---- L2CAP sequence number lists ---- */
313
314 /* For ERTM, ordered lists of sequence numbers must be tracked for
315 * SREJ requests that are received and for frames that are to be
316 * retransmitted. These seq_list functions implement a singly-linked
317 * list in an array, where membership in the list can also be checked
318 * in constant time. Items can also be added to the tail of the list
319 * and removed from the head in constant time, without further memory
320 * allocs or frees.
321 */
322
323 static int l2cap_seq_list_init(struct l2cap_seq_list *seq_list, u16 size)
324 {
325 size_t alloc_size, i;
326
327 /* Allocated size is a power of 2 to map sequence numbers
328 * (which may be up to 14 bits) in to a smaller array that is
329 * sized for the negotiated ERTM transmit windows.
330 */
331 alloc_size = roundup_pow_of_two(size);
332
333 seq_list->list = kmalloc(sizeof(u16) * alloc_size, GFP_KERNEL);
334 if (!seq_list->list)
335 return -ENOMEM;
336
337 seq_list->mask = alloc_size - 1;
338 seq_list->head = L2CAP_SEQ_LIST_CLEAR;
339 seq_list->tail = L2CAP_SEQ_LIST_CLEAR;
340 for (i = 0; i < alloc_size; i++)
341 seq_list->list[i] = L2CAP_SEQ_LIST_CLEAR;
342
343 return 0;
344 }
345
346 static inline void l2cap_seq_list_free(struct l2cap_seq_list *seq_list)
347 {
348 kfree(seq_list->list);
349 }
350
351 static inline bool l2cap_seq_list_contains(struct l2cap_seq_list *seq_list,
352 u16 seq)
353 {
354 /* Constant-time check for list membership */
355 return seq_list->list[seq & seq_list->mask] != L2CAP_SEQ_LIST_CLEAR;
356 }
357
358 static inline u16 l2cap_seq_list_pop(struct l2cap_seq_list *seq_list)
359 {
360 u16 seq = seq_list->head;
361 u16 mask = seq_list->mask;
362
363 seq_list->head = seq_list->list[seq & mask];
364 seq_list->list[seq & mask] = L2CAP_SEQ_LIST_CLEAR;
365
366 if (seq_list->head == L2CAP_SEQ_LIST_TAIL) {
367 seq_list->head = L2CAP_SEQ_LIST_CLEAR;
368 seq_list->tail = L2CAP_SEQ_LIST_CLEAR;
369 }
370
371 return seq;
372 }
373
374 static void l2cap_seq_list_clear(struct l2cap_seq_list *seq_list)
375 {
376 u16 i;
377
378 if (seq_list->head == L2CAP_SEQ_LIST_CLEAR)
379 return;
380
381 for (i = 0; i <= seq_list->mask; i++)
382 seq_list->list[i] = L2CAP_SEQ_LIST_CLEAR;
383
384 seq_list->head = L2CAP_SEQ_LIST_CLEAR;
385 seq_list->tail = L2CAP_SEQ_LIST_CLEAR;
386 }
387
388 static void l2cap_seq_list_append(struct l2cap_seq_list *seq_list, u16 seq)
389 {
390 u16 mask = seq_list->mask;
391
392 /* All appends happen in constant time */
393
394 if (seq_list->list[seq & mask] != L2CAP_SEQ_LIST_CLEAR)
395 return;
396
397 if (seq_list->tail == L2CAP_SEQ_LIST_CLEAR)
398 seq_list->head = seq;
399 else
400 seq_list->list[seq_list->tail & mask] = seq;
401
402 seq_list->tail = seq;
403 seq_list->list[seq & mask] = L2CAP_SEQ_LIST_TAIL;
404 }
405
406 static void l2cap_chan_timeout(struct work_struct *work)
407 {
408 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
409 chan_timer.work);
410 struct l2cap_conn *conn = chan->conn;
411 int reason;
412
413 BT_DBG("chan %p state %s", chan, state_to_string(chan->state));
414
415 mutex_lock(&conn->chan_lock);
416 l2cap_chan_lock(chan);
417
418 if (chan->state == BT_CONNECTED || chan->state == BT_CONFIG)
419 reason = ECONNREFUSED;
420 else if (chan->state == BT_CONNECT &&
421 chan->sec_level != BT_SECURITY_SDP)
422 reason = ECONNREFUSED;
423 else
424 reason = ETIMEDOUT;
425
426 l2cap_chan_close(chan, reason);
427
428 l2cap_chan_unlock(chan);
429
430 chan->ops->close(chan);
431 mutex_unlock(&conn->chan_lock);
432
433 l2cap_chan_put(chan);
434 }
435
436 struct l2cap_chan *l2cap_chan_create(void)
437 {
438 struct l2cap_chan *chan;
439
440 chan = kzalloc(sizeof(*chan), GFP_ATOMIC);
441 if (!chan)
442 return NULL;
443
444 mutex_init(&chan->lock);
445
446 /* Set default lock nesting level */
447 atomic_set(&chan->nesting, L2CAP_NESTING_NORMAL);
448
449 write_lock(&chan_list_lock);
450 list_add(&chan->global_l, &chan_list);
451 write_unlock(&chan_list_lock);
452
453 INIT_DELAYED_WORK(&chan->chan_timer, l2cap_chan_timeout);
454
455 chan->state = BT_OPEN;
456
457 kref_init(&chan->kref);
458
459 /* This flag is cleared in l2cap_chan_ready() */
460 set_bit(CONF_NOT_COMPLETE, &chan->conf_state);
461
462 BT_DBG("chan %p", chan);
463
464 return chan;
465 }
466 EXPORT_SYMBOL_GPL(l2cap_chan_create);
467
468 static void l2cap_chan_destroy(struct kref *kref)
469 {
470 struct l2cap_chan *chan = container_of(kref, struct l2cap_chan, kref);
471
472 BT_DBG("chan %p", chan);
473
474 write_lock(&chan_list_lock);
475 list_del(&chan->global_l);
476 write_unlock(&chan_list_lock);
477
478 kfree(chan);
479 }
480
481 void l2cap_chan_hold(struct l2cap_chan *c)
482 {
483 BT_DBG("chan %p orig refcnt %d", c, atomic_read(&c->kref.refcount));
484
485 kref_get(&c->kref);
486 }
487
488 void l2cap_chan_put(struct l2cap_chan *c)
489 {
490 BT_DBG("chan %p orig refcnt %d", c, atomic_read(&c->kref.refcount));
491
492 kref_put(&c->kref, l2cap_chan_destroy);
493 }
494 EXPORT_SYMBOL_GPL(l2cap_chan_put);
495
496 void l2cap_chan_set_defaults(struct l2cap_chan *chan)
497 {
498 chan->fcs = L2CAP_FCS_CRC16;
499 chan->max_tx = L2CAP_DEFAULT_MAX_TX;
500 chan->tx_win = L2CAP_DEFAULT_TX_WINDOW;
501 chan->tx_win_max = L2CAP_DEFAULT_TX_WINDOW;
502 chan->remote_max_tx = chan->max_tx;
503 chan->remote_tx_win = chan->tx_win;
504 chan->ack_win = L2CAP_DEFAULT_TX_WINDOW;
505 chan->sec_level = BT_SECURITY_LOW;
506 chan->flush_to = L2CAP_DEFAULT_FLUSH_TO;
507 chan->retrans_timeout = L2CAP_DEFAULT_RETRANS_TO;
508 chan->monitor_timeout = L2CAP_DEFAULT_MONITOR_TO;
509 chan->conf_state = 0;
510
511 set_bit(FLAG_FORCE_ACTIVE, &chan->flags);
512 }
513 EXPORT_SYMBOL_GPL(l2cap_chan_set_defaults);
514
515 static void l2cap_le_flowctl_init(struct l2cap_chan *chan)
516 {
517 chan->sdu = NULL;
518 chan->sdu_last_frag = NULL;
519 chan->sdu_len = 0;
520 chan->tx_credits = 0;
521 chan->rx_credits = le_max_credits;
522 chan->mps = min_t(u16, chan->imtu, le_default_mps);
523
524 skb_queue_head_init(&chan->tx_q);
525 }
526
527 void __l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan)
528 {
529 BT_DBG("conn %p, psm 0x%2.2x, dcid 0x%4.4x", conn,
530 __le16_to_cpu(chan->psm), chan->dcid);
531
532 conn->disc_reason = HCI_ERROR_REMOTE_USER_TERM;
533
534 chan->conn = conn;
535
536 switch (chan->chan_type) {
537 case L2CAP_CHAN_CONN_ORIENTED:
538 /* Alloc CID for connection-oriented socket */
539 chan->scid = l2cap_alloc_cid(conn);
540 if (conn->hcon->type == ACL_LINK)
541 chan->omtu = L2CAP_DEFAULT_MTU;
542 break;
543
544 case L2CAP_CHAN_CONN_LESS:
545 /* Connectionless socket */
546 chan->scid = L2CAP_CID_CONN_LESS;
547 chan->dcid = L2CAP_CID_CONN_LESS;
548 chan->omtu = L2CAP_DEFAULT_MTU;
549 break;
550
551 case L2CAP_CHAN_FIXED:
552 /* Caller will set CID and CID specific MTU values */
553 break;
554
555 default:
556 /* Raw socket can send/recv signalling messages only */
557 chan->scid = L2CAP_CID_SIGNALING;
558 chan->dcid = L2CAP_CID_SIGNALING;
559 chan->omtu = L2CAP_DEFAULT_MTU;
560 }
561
562 chan->local_id = L2CAP_BESTEFFORT_ID;
563 chan->local_stype = L2CAP_SERV_BESTEFFORT;
564 chan->local_msdu = L2CAP_DEFAULT_MAX_SDU_SIZE;
565 chan->local_sdu_itime = L2CAP_DEFAULT_SDU_ITIME;
566 chan->local_acc_lat = L2CAP_DEFAULT_ACC_LAT;
567 chan->local_flush_to = L2CAP_EFS_DEFAULT_FLUSH_TO;
568
569 l2cap_chan_hold(chan);
570
571 /* Only keep a reference for fixed channels if they requested it */
572 if (chan->chan_type != L2CAP_CHAN_FIXED ||
573 test_bit(FLAG_HOLD_HCI_CONN, &chan->flags))
574 hci_conn_hold(conn->hcon);
575
576 list_add(&chan->list, &conn->chan_l);
577 }
578
579 void l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan)
580 {
581 mutex_lock(&conn->chan_lock);
582 __l2cap_chan_add(conn, chan);
583 mutex_unlock(&conn->chan_lock);
584 }
585
586 void l2cap_chan_del(struct l2cap_chan *chan, int err)
587 {
588 struct l2cap_conn *conn = chan->conn;
589
590 __clear_chan_timer(chan);
591
592 BT_DBG("chan %p, conn %p, err %d, state %s", chan, conn, err,
593 state_to_string(chan->state));
594
595 chan->ops->teardown(chan, err);
596
597 if (conn) {
598 struct amp_mgr *mgr = conn->hcon->amp_mgr;
599 /* Delete from channel list */
600 list_del(&chan->list);
601
602 l2cap_chan_put(chan);
603
604 chan->conn = NULL;
605
606 /* Reference was only held for non-fixed channels or
607 * fixed channels that explicitly requested it using the
608 * FLAG_HOLD_HCI_CONN flag.
609 */
610 if (chan->chan_type != L2CAP_CHAN_FIXED ||
611 test_bit(FLAG_HOLD_HCI_CONN, &chan->flags))
612 hci_conn_drop(conn->hcon);
613
614 if (mgr && mgr->bredr_chan == chan)
615 mgr->bredr_chan = NULL;
616 }
617
618 if (chan->hs_hchan) {
619 struct hci_chan *hs_hchan = chan->hs_hchan;
620
621 BT_DBG("chan %p disconnect hs_hchan %p", chan, hs_hchan);
622 amp_disconnect_logical_link(hs_hchan);
623 }
624
625 if (test_bit(CONF_NOT_COMPLETE, &chan->conf_state))
626 return;
627
628 switch(chan->mode) {
629 case L2CAP_MODE_BASIC:
630 break;
631
632 case L2CAP_MODE_LE_FLOWCTL:
633 skb_queue_purge(&chan->tx_q);
634 break;
635
636 case L2CAP_MODE_ERTM:
637 __clear_retrans_timer(chan);
638 __clear_monitor_timer(chan);
639 __clear_ack_timer(chan);
640
641 skb_queue_purge(&chan->srej_q);
642
643 l2cap_seq_list_free(&chan->srej_list);
644 l2cap_seq_list_free(&chan->retrans_list);
645
646 /* fall through */
647
648 case L2CAP_MODE_STREAMING:
649 skb_queue_purge(&chan->tx_q);
650 break;
651 }
652
653 return;
654 }
655 EXPORT_SYMBOL_GPL(l2cap_chan_del);
656
657 static void l2cap_conn_update_id_addr(struct work_struct *work)
658 {
659 struct l2cap_conn *conn = container_of(work, struct l2cap_conn,
660 id_addr_update_work);
661 struct hci_conn *hcon = conn->hcon;
662 struct l2cap_chan *chan;
663
664 mutex_lock(&conn->chan_lock);
665
666 list_for_each_entry(chan, &conn->chan_l, list) {
667 l2cap_chan_lock(chan);
668 bacpy(&chan->dst, &hcon->dst);
669 chan->dst_type = bdaddr_dst_type(hcon);
670 l2cap_chan_unlock(chan);
671 }
672
673 mutex_unlock(&conn->chan_lock);
674 }
675
676 static void l2cap_chan_le_connect_reject(struct l2cap_chan *chan)
677 {
678 struct l2cap_conn *conn = chan->conn;
679 struct l2cap_le_conn_rsp rsp;
680 u16 result;
681
682 if (test_bit(FLAG_DEFER_SETUP, &chan->flags))
683 result = L2CAP_CR_AUTHORIZATION;
684 else
685 result = L2CAP_CR_BAD_PSM;
686
687 l2cap_state_change(chan, BT_DISCONN);
688
689 rsp.dcid = cpu_to_le16(chan->scid);
690 rsp.mtu = cpu_to_le16(chan->imtu);
691 rsp.mps = cpu_to_le16(chan->mps);
692 rsp.credits = cpu_to_le16(chan->rx_credits);
693 rsp.result = cpu_to_le16(result);
694
695 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CONN_RSP, sizeof(rsp),
696 &rsp);
697 }
698
699 static void l2cap_chan_connect_reject(struct l2cap_chan *chan)
700 {
701 struct l2cap_conn *conn = chan->conn;
702 struct l2cap_conn_rsp rsp;
703 u16 result;
704
705 if (test_bit(FLAG_DEFER_SETUP, &chan->flags))
706 result = L2CAP_CR_SEC_BLOCK;
707 else
708 result = L2CAP_CR_BAD_PSM;
709
710 l2cap_state_change(chan, BT_DISCONN);
711
712 rsp.scid = cpu_to_le16(chan->dcid);
713 rsp.dcid = cpu_to_le16(chan->scid);
714 rsp.result = cpu_to_le16(result);
715 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
716
717 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP, sizeof(rsp), &rsp);
718 }
719
720 void l2cap_chan_close(struct l2cap_chan *chan, int reason)
721 {
722 struct l2cap_conn *conn = chan->conn;
723
724 BT_DBG("chan %p state %s", chan, state_to_string(chan->state));
725
726 switch (chan->state) {
727 case BT_LISTEN:
728 chan->ops->teardown(chan, 0);
729 break;
730
731 case BT_CONNECTED:
732 case BT_CONFIG:
733 if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED) {
734 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
735 l2cap_send_disconn_req(chan, reason);
736 } else
737 l2cap_chan_del(chan, reason);
738 break;
739
740 case BT_CONNECT2:
741 if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED) {
742 if (conn->hcon->type == ACL_LINK)
743 l2cap_chan_connect_reject(chan);
744 else if (conn->hcon->type == LE_LINK)
745 l2cap_chan_le_connect_reject(chan);
746 }
747
748 l2cap_chan_del(chan, reason);
749 break;
750
751 case BT_CONNECT:
752 case BT_DISCONN:
753 l2cap_chan_del(chan, reason);
754 break;
755
756 default:
757 chan->ops->teardown(chan, 0);
758 break;
759 }
760 }
761 EXPORT_SYMBOL(l2cap_chan_close);
762
763 static inline u8 l2cap_get_auth_type(struct l2cap_chan *chan)
764 {
765 switch (chan->chan_type) {
766 case L2CAP_CHAN_RAW:
767 switch (chan->sec_level) {
768 case BT_SECURITY_HIGH:
769 case BT_SECURITY_FIPS:
770 return HCI_AT_DEDICATED_BONDING_MITM;
771 case BT_SECURITY_MEDIUM:
772 return HCI_AT_DEDICATED_BONDING;
773 default:
774 return HCI_AT_NO_BONDING;
775 }
776 break;
777 case L2CAP_CHAN_CONN_LESS:
778 if (chan->psm == cpu_to_le16(L2CAP_PSM_3DSP)) {
779 if (chan->sec_level == BT_SECURITY_LOW)
780 chan->sec_level = BT_SECURITY_SDP;
781 }
782 if (chan->sec_level == BT_SECURITY_HIGH ||
783 chan->sec_level == BT_SECURITY_FIPS)
784 return HCI_AT_NO_BONDING_MITM;
785 else
786 return HCI_AT_NO_BONDING;
787 break;
788 case L2CAP_CHAN_CONN_ORIENTED:
789 if (chan->psm == cpu_to_le16(L2CAP_PSM_SDP)) {
790 if (chan->sec_level == BT_SECURITY_LOW)
791 chan->sec_level = BT_SECURITY_SDP;
792
793 if (chan->sec_level == BT_SECURITY_HIGH ||
794 chan->sec_level == BT_SECURITY_FIPS)
795 return HCI_AT_NO_BONDING_MITM;
796 else
797 return HCI_AT_NO_BONDING;
798 }
799 /* fall through */
800 default:
801 switch (chan->sec_level) {
802 case BT_SECURITY_HIGH:
803 case BT_SECURITY_FIPS:
804 return HCI_AT_GENERAL_BONDING_MITM;
805 case BT_SECURITY_MEDIUM:
806 return HCI_AT_GENERAL_BONDING;
807 default:
808 return HCI_AT_NO_BONDING;
809 }
810 break;
811 }
812 }
813
814 /* Service level security */
815 int l2cap_chan_check_security(struct l2cap_chan *chan, bool initiator)
816 {
817 struct l2cap_conn *conn = chan->conn;
818 __u8 auth_type;
819
820 if (conn->hcon->type == LE_LINK)
821 return smp_conn_security(conn->hcon, chan->sec_level);
822
823 auth_type = l2cap_get_auth_type(chan);
824
825 return hci_conn_security(conn->hcon, chan->sec_level, auth_type,
826 initiator);
827 }
828
829 static u8 l2cap_get_ident(struct l2cap_conn *conn)
830 {
831 u8 id;
832
833 /* Get next available identificator.
834 * 1 - 128 are used by kernel.
835 * 129 - 199 are reserved.
836 * 200 - 254 are used by utilities like l2ping, etc.
837 */
838
839 mutex_lock(&conn->ident_lock);
840
841 if (++conn->tx_ident > 128)
842 conn->tx_ident = 1;
843
844 id = conn->tx_ident;
845
846 mutex_unlock(&conn->ident_lock);
847
848 return id;
849 }
850
851 static void l2cap_send_cmd(struct l2cap_conn *conn, u8 ident, u8 code, u16 len,
852 void *data)
853 {
854 struct sk_buff *skb = l2cap_build_cmd(conn, code, ident, len, data);
855 u8 flags;
856
857 BT_DBG("code 0x%2.2x", code);
858
859 if (!skb)
860 return;
861
862 /* Use NO_FLUSH if supported or we have an LE link (which does
863 * not support auto-flushing packets) */
864 if (lmp_no_flush_capable(conn->hcon->hdev) ||
865 conn->hcon->type == LE_LINK)
866 flags = ACL_START_NO_FLUSH;
867 else
868 flags = ACL_START;
869
870 bt_cb(skb)->force_active = BT_POWER_FORCE_ACTIVE_ON;
871 skb->priority = HCI_PRIO_MAX;
872
873 hci_send_acl(conn->hchan, skb, flags);
874 }
875
876 static bool __chan_is_moving(struct l2cap_chan *chan)
877 {
878 return chan->move_state != L2CAP_MOVE_STABLE &&
879 chan->move_state != L2CAP_MOVE_WAIT_PREPARE;
880 }
881
882 static void l2cap_do_send(struct l2cap_chan *chan, struct sk_buff *skb)
883 {
884 struct hci_conn *hcon = chan->conn->hcon;
885 u16 flags;
886
887 BT_DBG("chan %p, skb %p len %d priority %u", chan, skb, skb->len,
888 skb->priority);
889
890 if (chan->hs_hcon && !__chan_is_moving(chan)) {
891 if (chan->hs_hchan)
892 hci_send_acl(chan->hs_hchan, skb, ACL_COMPLETE);
893 else
894 kfree_skb(skb);
895
896 return;
897 }
898
899 /* Use NO_FLUSH for LE links (where this is the only option) or
900 * if the BR/EDR link supports it and flushing has not been
901 * explicitly requested (through FLAG_FLUSHABLE).
902 */
903 if (hcon->type == LE_LINK ||
904 (!test_bit(FLAG_FLUSHABLE, &chan->flags) &&
905 lmp_no_flush_capable(hcon->hdev)))
906 flags = ACL_START_NO_FLUSH;
907 else
908 flags = ACL_START;
909
910 bt_cb(skb)->force_active = test_bit(FLAG_FORCE_ACTIVE, &chan->flags);
911 hci_send_acl(chan->conn->hchan, skb, flags);
912 }
913
914 static void __unpack_enhanced_control(u16 enh, struct l2cap_ctrl *control)
915 {
916 control->reqseq = (enh & L2CAP_CTRL_REQSEQ) >> L2CAP_CTRL_REQSEQ_SHIFT;
917 control->final = (enh & L2CAP_CTRL_FINAL) >> L2CAP_CTRL_FINAL_SHIFT;
918
919 if (enh & L2CAP_CTRL_FRAME_TYPE) {
920 /* S-Frame */
921 control->sframe = 1;
922 control->poll = (enh & L2CAP_CTRL_POLL) >> L2CAP_CTRL_POLL_SHIFT;
923 control->super = (enh & L2CAP_CTRL_SUPERVISE) >> L2CAP_CTRL_SUPER_SHIFT;
924
925 control->sar = 0;
926 control->txseq = 0;
927 } else {
928 /* I-Frame */
929 control->sframe = 0;
930 control->sar = (enh & L2CAP_CTRL_SAR) >> L2CAP_CTRL_SAR_SHIFT;
931 control->txseq = (enh & L2CAP_CTRL_TXSEQ) >> L2CAP_CTRL_TXSEQ_SHIFT;
932
933 control->poll = 0;
934 control->super = 0;
935 }
936 }
937
938 static void __unpack_extended_control(u32 ext, struct l2cap_ctrl *control)
939 {
940 control->reqseq = (ext & L2CAP_EXT_CTRL_REQSEQ) >> L2CAP_EXT_CTRL_REQSEQ_SHIFT;
941 control->final = (ext & L2CAP_EXT_CTRL_FINAL) >> L2CAP_EXT_CTRL_FINAL_SHIFT;
942
943 if (ext & L2CAP_EXT_CTRL_FRAME_TYPE) {
944 /* S-Frame */
945 control->sframe = 1;
946 control->poll = (ext & L2CAP_EXT_CTRL_POLL) >> L2CAP_EXT_CTRL_POLL_SHIFT;
947 control->super = (ext & L2CAP_EXT_CTRL_SUPERVISE) >> L2CAP_EXT_CTRL_SUPER_SHIFT;
948
949 control->sar = 0;
950 control->txseq = 0;
951 } else {
952 /* I-Frame */
953 control->sframe = 0;
954 control->sar = (ext & L2CAP_EXT_CTRL_SAR) >> L2CAP_EXT_CTRL_SAR_SHIFT;
955 control->txseq = (ext & L2CAP_EXT_CTRL_TXSEQ) >> L2CAP_EXT_CTRL_TXSEQ_SHIFT;
956
957 control->poll = 0;
958 control->super = 0;
959 }
960 }
961
962 static inline void __unpack_control(struct l2cap_chan *chan,
963 struct sk_buff *skb)
964 {
965 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) {
966 __unpack_extended_control(get_unaligned_le32(skb->data),
967 &bt_cb(skb)->l2cap);
968 skb_pull(skb, L2CAP_EXT_CTRL_SIZE);
969 } else {
970 __unpack_enhanced_control(get_unaligned_le16(skb->data),
971 &bt_cb(skb)->l2cap);
972 skb_pull(skb, L2CAP_ENH_CTRL_SIZE);
973 }
974 }
975
976 static u32 __pack_extended_control(struct l2cap_ctrl *control)
977 {
978 u32 packed;
979
980 packed = control->reqseq << L2CAP_EXT_CTRL_REQSEQ_SHIFT;
981 packed |= control->final << L2CAP_EXT_CTRL_FINAL_SHIFT;
982
983 if (control->sframe) {
984 packed |= control->poll << L2CAP_EXT_CTRL_POLL_SHIFT;
985 packed |= control->super << L2CAP_EXT_CTRL_SUPER_SHIFT;
986 packed |= L2CAP_EXT_CTRL_FRAME_TYPE;
987 } else {
988 packed |= control->sar << L2CAP_EXT_CTRL_SAR_SHIFT;
989 packed |= control->txseq << L2CAP_EXT_CTRL_TXSEQ_SHIFT;
990 }
991
992 return packed;
993 }
994
995 static u16 __pack_enhanced_control(struct l2cap_ctrl *control)
996 {
997 u16 packed;
998
999 packed = control->reqseq << L2CAP_CTRL_REQSEQ_SHIFT;
1000 packed |= control->final << L2CAP_CTRL_FINAL_SHIFT;
1001
1002 if (control->sframe) {
1003 packed |= control->poll << L2CAP_CTRL_POLL_SHIFT;
1004 packed |= control->super << L2CAP_CTRL_SUPER_SHIFT;
1005 packed |= L2CAP_CTRL_FRAME_TYPE;
1006 } else {
1007 packed |= control->sar << L2CAP_CTRL_SAR_SHIFT;
1008 packed |= control->txseq << L2CAP_CTRL_TXSEQ_SHIFT;
1009 }
1010
1011 return packed;
1012 }
1013
1014 static inline void __pack_control(struct l2cap_chan *chan,
1015 struct l2cap_ctrl *control,
1016 struct sk_buff *skb)
1017 {
1018 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) {
1019 put_unaligned_le32(__pack_extended_control(control),
1020 skb->data + L2CAP_HDR_SIZE);
1021 } else {
1022 put_unaligned_le16(__pack_enhanced_control(control),
1023 skb->data + L2CAP_HDR_SIZE);
1024 }
1025 }
1026
1027 static inline unsigned int __ertm_hdr_size(struct l2cap_chan *chan)
1028 {
1029 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
1030 return L2CAP_EXT_HDR_SIZE;
1031 else
1032 return L2CAP_ENH_HDR_SIZE;
1033 }
1034
1035 static struct sk_buff *l2cap_create_sframe_pdu(struct l2cap_chan *chan,
1036 u32 control)
1037 {
1038 struct sk_buff *skb;
1039 struct l2cap_hdr *lh;
1040 int hlen = __ertm_hdr_size(chan);
1041
1042 if (chan->fcs == L2CAP_FCS_CRC16)
1043 hlen += L2CAP_FCS_SIZE;
1044
1045 skb = bt_skb_alloc(hlen, GFP_KERNEL);
1046
1047 if (!skb)
1048 return ERR_PTR(-ENOMEM);
1049
1050 lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
1051 lh->len = cpu_to_le16(hlen - L2CAP_HDR_SIZE);
1052 lh->cid = cpu_to_le16(chan->dcid);
1053
1054 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
1055 put_unaligned_le32(control, skb_put(skb, L2CAP_EXT_CTRL_SIZE));
1056 else
1057 put_unaligned_le16(control, skb_put(skb, L2CAP_ENH_CTRL_SIZE));
1058
1059 if (chan->fcs == L2CAP_FCS_CRC16) {
1060 u16 fcs = crc16(0, (u8 *)skb->data, skb->len);
1061 put_unaligned_le16(fcs, skb_put(skb, L2CAP_FCS_SIZE));
1062 }
1063
1064 skb->priority = HCI_PRIO_MAX;
1065 return skb;
1066 }
1067
1068 static void l2cap_send_sframe(struct l2cap_chan *chan,
1069 struct l2cap_ctrl *control)
1070 {
1071 struct sk_buff *skb;
1072 u32 control_field;
1073
1074 BT_DBG("chan %p, control %p", chan, control);
1075
1076 if (!control->sframe)
1077 return;
1078
1079 if (__chan_is_moving(chan))
1080 return;
1081
1082 if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state) &&
1083 !control->poll)
1084 control->final = 1;
1085
1086 if (control->super == L2CAP_SUPER_RR)
1087 clear_bit(CONN_RNR_SENT, &chan->conn_state);
1088 else if (control->super == L2CAP_SUPER_RNR)
1089 set_bit(CONN_RNR_SENT, &chan->conn_state);
1090
1091 if (control->super != L2CAP_SUPER_SREJ) {
1092 chan->last_acked_seq = control->reqseq;
1093 __clear_ack_timer(chan);
1094 }
1095
1096 BT_DBG("reqseq %d, final %d, poll %d, super %d", control->reqseq,
1097 control->final, control->poll, control->super);
1098
1099 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
1100 control_field = __pack_extended_control(control);
1101 else
1102 control_field = __pack_enhanced_control(control);
1103
1104 skb = l2cap_create_sframe_pdu(chan, control_field);
1105 if (!IS_ERR(skb))
1106 l2cap_do_send(chan, skb);
1107 }
1108
1109 static void l2cap_send_rr_or_rnr(struct l2cap_chan *chan, bool poll)
1110 {
1111 struct l2cap_ctrl control;
1112
1113 BT_DBG("chan %p, poll %d", chan, poll);
1114
1115 memset(&control, 0, sizeof(control));
1116 control.sframe = 1;
1117 control.poll = poll;
1118
1119 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state))
1120 control.super = L2CAP_SUPER_RNR;
1121 else
1122 control.super = L2CAP_SUPER_RR;
1123
1124 control.reqseq = chan->buffer_seq;
1125 l2cap_send_sframe(chan, &control);
1126 }
1127
1128 static inline int __l2cap_no_conn_pending(struct l2cap_chan *chan)
1129 {
1130 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED)
1131 return true;
1132
1133 return !test_bit(CONF_CONNECT_PEND, &chan->conf_state);
1134 }
1135
1136 static bool __amp_capable(struct l2cap_chan *chan)
1137 {
1138 struct l2cap_conn *conn = chan->conn;
1139 struct hci_dev *hdev;
1140 bool amp_available = false;
1141
1142 if (!(conn->local_fixed_chan & L2CAP_FC_A2MP))
1143 return false;
1144
1145 if (!(conn->remote_fixed_chan & L2CAP_FC_A2MP))
1146 return false;
1147
1148 read_lock(&hci_dev_list_lock);
1149 list_for_each_entry(hdev, &hci_dev_list, list) {
1150 if (hdev->amp_type != AMP_TYPE_BREDR &&
1151 test_bit(HCI_UP, &hdev->flags)) {
1152 amp_available = true;
1153 break;
1154 }
1155 }
1156 read_unlock(&hci_dev_list_lock);
1157
1158 if (chan->chan_policy == BT_CHANNEL_POLICY_AMP_PREFERRED)
1159 return amp_available;
1160
1161 return false;
1162 }
1163
1164 static bool l2cap_check_efs(struct l2cap_chan *chan)
1165 {
1166 /* Check EFS parameters */
1167 return true;
1168 }
1169
1170 void l2cap_send_conn_req(struct l2cap_chan *chan)
1171 {
1172 struct l2cap_conn *conn = chan->conn;
1173 struct l2cap_conn_req req;
1174
1175 req.scid = cpu_to_le16(chan->scid);
1176 req.psm = chan->psm;
1177
1178 chan->ident = l2cap_get_ident(conn);
1179
1180 set_bit(CONF_CONNECT_PEND, &chan->conf_state);
1181
1182 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_REQ, sizeof(req), &req);
1183 }
1184
1185 static void l2cap_send_create_chan_req(struct l2cap_chan *chan, u8 amp_id)
1186 {
1187 struct l2cap_create_chan_req req;
1188 req.scid = cpu_to_le16(chan->scid);
1189 req.psm = chan->psm;
1190 req.amp_id = amp_id;
1191
1192 chan->ident = l2cap_get_ident(chan->conn);
1193
1194 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_CREATE_CHAN_REQ,
1195 sizeof(req), &req);
1196 }
1197
1198 static void l2cap_move_setup(struct l2cap_chan *chan)
1199 {
1200 struct sk_buff *skb;
1201
1202 BT_DBG("chan %p", chan);
1203
1204 if (chan->mode != L2CAP_MODE_ERTM)
1205 return;
1206
1207 __clear_retrans_timer(chan);
1208 __clear_monitor_timer(chan);
1209 __clear_ack_timer(chan);
1210
1211 chan->retry_count = 0;
1212 skb_queue_walk(&chan->tx_q, skb) {
1213 if (bt_cb(skb)->l2cap.retries)
1214 bt_cb(skb)->l2cap.retries = 1;
1215 else
1216 break;
1217 }
1218
1219 chan->expected_tx_seq = chan->buffer_seq;
1220
1221 clear_bit(CONN_REJ_ACT, &chan->conn_state);
1222 clear_bit(CONN_SREJ_ACT, &chan->conn_state);
1223 l2cap_seq_list_clear(&chan->retrans_list);
1224 l2cap_seq_list_clear(&chan->srej_list);
1225 skb_queue_purge(&chan->srej_q);
1226
1227 chan->tx_state = L2CAP_TX_STATE_XMIT;
1228 chan->rx_state = L2CAP_RX_STATE_MOVE;
1229
1230 set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
1231 }
1232
1233 static void l2cap_move_done(struct l2cap_chan *chan)
1234 {
1235 u8 move_role = chan->move_role;
1236 BT_DBG("chan %p", chan);
1237
1238 chan->move_state = L2CAP_MOVE_STABLE;
1239 chan->move_role = L2CAP_MOVE_ROLE_NONE;
1240
1241 if (chan->mode != L2CAP_MODE_ERTM)
1242 return;
1243
1244 switch (move_role) {
1245 case L2CAP_MOVE_ROLE_INITIATOR:
1246 l2cap_tx(chan, NULL, NULL, L2CAP_EV_EXPLICIT_POLL);
1247 chan->rx_state = L2CAP_RX_STATE_WAIT_F;
1248 break;
1249 case L2CAP_MOVE_ROLE_RESPONDER:
1250 chan->rx_state = L2CAP_RX_STATE_WAIT_P;
1251 break;
1252 }
1253 }
1254
1255 static void l2cap_chan_ready(struct l2cap_chan *chan)
1256 {
1257 /* The channel may have already been flagged as connected in
1258 * case of receiving data before the L2CAP info req/rsp
1259 * procedure is complete.
1260 */
1261 if (chan->state == BT_CONNECTED)
1262 return;
1263
1264 /* This clears all conf flags, including CONF_NOT_COMPLETE */
1265 chan->conf_state = 0;
1266 __clear_chan_timer(chan);
1267
1268 if (chan->mode == L2CAP_MODE_LE_FLOWCTL && !chan->tx_credits)
1269 chan->ops->suspend(chan);
1270
1271 chan->state = BT_CONNECTED;
1272
1273 chan->ops->ready(chan);
1274 }
1275
1276 static void l2cap_le_connect(struct l2cap_chan *chan)
1277 {
1278 struct l2cap_conn *conn = chan->conn;
1279 struct l2cap_le_conn_req req;
1280
1281 if (test_and_set_bit(FLAG_LE_CONN_REQ_SENT, &chan->flags))
1282 return;
1283
1284 req.psm = chan->psm;
1285 req.scid = cpu_to_le16(chan->scid);
1286 req.mtu = cpu_to_le16(chan->imtu);
1287 req.mps = cpu_to_le16(chan->mps);
1288 req.credits = cpu_to_le16(chan->rx_credits);
1289
1290 chan->ident = l2cap_get_ident(conn);
1291
1292 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CONN_REQ,
1293 sizeof(req), &req);
1294 }
1295
1296 static void l2cap_le_start(struct l2cap_chan *chan)
1297 {
1298 struct l2cap_conn *conn = chan->conn;
1299
1300 if (!smp_conn_security(conn->hcon, chan->sec_level))
1301 return;
1302
1303 if (!chan->psm) {
1304 l2cap_chan_ready(chan);
1305 return;
1306 }
1307
1308 if (chan->state == BT_CONNECT)
1309 l2cap_le_connect(chan);
1310 }
1311
1312 static void l2cap_start_connection(struct l2cap_chan *chan)
1313 {
1314 if (__amp_capable(chan)) {
1315 BT_DBG("chan %p AMP capable: discover AMPs", chan);
1316 a2mp_discover_amp(chan);
1317 } else if (chan->conn->hcon->type == LE_LINK) {
1318 l2cap_le_start(chan);
1319 } else {
1320 l2cap_send_conn_req(chan);
1321 }
1322 }
1323
1324 static void l2cap_request_info(struct l2cap_conn *conn)
1325 {
1326 struct l2cap_info_req req;
1327
1328 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT)
1329 return;
1330
1331 req.type = cpu_to_le16(L2CAP_IT_FEAT_MASK);
1332
1333 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_SENT;
1334 conn->info_ident = l2cap_get_ident(conn);
1335
1336 schedule_delayed_work(&conn->info_timer, L2CAP_INFO_TIMEOUT);
1337
1338 l2cap_send_cmd(conn, conn->info_ident, L2CAP_INFO_REQ,
1339 sizeof(req), &req);
1340 }
1341
1342 static void l2cap_do_start(struct l2cap_chan *chan)
1343 {
1344 struct l2cap_conn *conn = chan->conn;
1345
1346 if (conn->hcon->type == LE_LINK) {
1347 l2cap_le_start(chan);
1348 return;
1349 }
1350
1351 if (!(conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT)) {
1352 l2cap_request_info(conn);
1353 return;
1354 }
1355
1356 if (!(conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE))
1357 return;
1358
1359 if (l2cap_chan_check_security(chan, true) &&
1360 __l2cap_no_conn_pending(chan))
1361 l2cap_start_connection(chan);
1362 }
1363
1364 static inline int l2cap_mode_supported(__u8 mode, __u32 feat_mask)
1365 {
1366 u32 local_feat_mask = l2cap_feat_mask;
1367 if (!disable_ertm)
1368 local_feat_mask |= L2CAP_FEAT_ERTM | L2CAP_FEAT_STREAMING;
1369
1370 switch (mode) {
1371 case L2CAP_MODE_ERTM:
1372 return L2CAP_FEAT_ERTM & feat_mask & local_feat_mask;
1373 case L2CAP_MODE_STREAMING:
1374 return L2CAP_FEAT_STREAMING & feat_mask & local_feat_mask;
1375 default:
1376 return 0x00;
1377 }
1378 }
1379
1380 static void l2cap_send_disconn_req(struct l2cap_chan *chan, int err)
1381 {
1382 struct l2cap_conn *conn = chan->conn;
1383 struct l2cap_disconn_req req;
1384
1385 if (!conn)
1386 return;
1387
1388 if (chan->mode == L2CAP_MODE_ERTM && chan->state == BT_CONNECTED) {
1389 __clear_retrans_timer(chan);
1390 __clear_monitor_timer(chan);
1391 __clear_ack_timer(chan);
1392 }
1393
1394 if (chan->scid == L2CAP_CID_A2MP) {
1395 l2cap_state_change(chan, BT_DISCONN);
1396 return;
1397 }
1398
1399 req.dcid = cpu_to_le16(chan->dcid);
1400 req.scid = cpu_to_le16(chan->scid);
1401 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_DISCONN_REQ,
1402 sizeof(req), &req);
1403
1404 l2cap_state_change_and_error(chan, BT_DISCONN, err);
1405 }
1406
1407 /* ---- L2CAP connections ---- */
1408 static void l2cap_conn_start(struct l2cap_conn *conn)
1409 {
1410 struct l2cap_chan *chan, *tmp;
1411
1412 BT_DBG("conn %p", conn);
1413
1414 mutex_lock(&conn->chan_lock);
1415
1416 list_for_each_entry_safe(chan, tmp, &conn->chan_l, list) {
1417 l2cap_chan_lock(chan);
1418
1419 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
1420 l2cap_chan_ready(chan);
1421 l2cap_chan_unlock(chan);
1422 continue;
1423 }
1424
1425 if (chan->state == BT_CONNECT) {
1426 if (!l2cap_chan_check_security(chan, true) ||
1427 !__l2cap_no_conn_pending(chan)) {
1428 l2cap_chan_unlock(chan);
1429 continue;
1430 }
1431
1432 if (!l2cap_mode_supported(chan->mode, conn->feat_mask)
1433 && test_bit(CONF_STATE2_DEVICE,
1434 &chan->conf_state)) {
1435 l2cap_chan_close(chan, ECONNRESET);
1436 l2cap_chan_unlock(chan);
1437 continue;
1438 }
1439
1440 l2cap_start_connection(chan);
1441
1442 } else if (chan->state == BT_CONNECT2) {
1443 struct l2cap_conn_rsp rsp;
1444 char buf[128];
1445 rsp.scid = cpu_to_le16(chan->dcid);
1446 rsp.dcid = cpu_to_le16(chan->scid);
1447
1448 if (l2cap_chan_check_security(chan, false)) {
1449 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
1450 rsp.result = cpu_to_le16(L2CAP_CR_PEND);
1451 rsp.status = cpu_to_le16(L2CAP_CS_AUTHOR_PEND);
1452 chan->ops->defer(chan);
1453
1454 } else {
1455 l2cap_state_change(chan, BT_CONFIG);
1456 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
1457 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
1458 }
1459 } else {
1460 rsp.result = cpu_to_le16(L2CAP_CR_PEND);
1461 rsp.status = cpu_to_le16(L2CAP_CS_AUTHEN_PEND);
1462 }
1463
1464 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP,
1465 sizeof(rsp), &rsp);
1466
1467 if (test_bit(CONF_REQ_SENT, &chan->conf_state) ||
1468 rsp.result != L2CAP_CR_SUCCESS) {
1469 l2cap_chan_unlock(chan);
1470 continue;
1471 }
1472
1473 set_bit(CONF_REQ_SENT, &chan->conf_state);
1474 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
1475 l2cap_build_conf_req(chan, buf), buf);
1476 chan->num_conf_req++;
1477 }
1478
1479 l2cap_chan_unlock(chan);
1480 }
1481
1482 mutex_unlock(&conn->chan_lock);
1483 }
1484
1485 static void l2cap_le_conn_ready(struct l2cap_conn *conn)
1486 {
1487 struct hci_conn *hcon = conn->hcon;
1488 struct hci_dev *hdev = hcon->hdev;
1489
1490 BT_DBG("%s conn %p", hdev->name, conn);
1491
1492 /* For outgoing pairing which doesn't necessarily have an
1493 * associated socket (e.g. mgmt_pair_device).
1494 */
1495 if (hcon->out)
1496 smp_conn_security(hcon, hcon->pending_sec_level);
1497
1498 /* For LE slave connections, make sure the connection interval
1499 * is in the range of the minium and maximum interval that has
1500 * been configured for this connection. If not, then trigger
1501 * the connection update procedure.
1502 */
1503 if (hcon->role == HCI_ROLE_SLAVE &&
1504 (hcon->le_conn_interval < hcon->le_conn_min_interval ||
1505 hcon->le_conn_interval > hcon->le_conn_max_interval)) {
1506 struct l2cap_conn_param_update_req req;
1507
1508 req.min = cpu_to_le16(hcon->le_conn_min_interval);
1509 req.max = cpu_to_le16(hcon->le_conn_max_interval);
1510 req.latency = cpu_to_le16(hcon->le_conn_latency);
1511 req.to_multiplier = cpu_to_le16(hcon->le_supv_timeout);
1512
1513 l2cap_send_cmd(conn, l2cap_get_ident(conn),
1514 L2CAP_CONN_PARAM_UPDATE_REQ, sizeof(req), &req);
1515 }
1516 }
1517
1518 static void l2cap_conn_ready(struct l2cap_conn *conn)
1519 {
1520 struct l2cap_chan *chan;
1521 struct hci_conn *hcon = conn->hcon;
1522
1523 BT_DBG("conn %p", conn);
1524
1525 if (hcon->type == ACL_LINK)
1526 l2cap_request_info(conn);
1527
1528 mutex_lock(&conn->chan_lock);
1529
1530 list_for_each_entry(chan, &conn->chan_l, list) {
1531
1532 l2cap_chan_lock(chan);
1533
1534 if (chan->scid == L2CAP_CID_A2MP) {
1535 l2cap_chan_unlock(chan);
1536 continue;
1537 }
1538
1539 if (hcon->type == LE_LINK) {
1540 l2cap_le_start(chan);
1541 } else if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
1542 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE)
1543 l2cap_chan_ready(chan);
1544 } else if (chan->state == BT_CONNECT) {
1545 l2cap_do_start(chan);
1546 }
1547
1548 l2cap_chan_unlock(chan);
1549 }
1550
1551 mutex_unlock(&conn->chan_lock);
1552
1553 if (hcon->type == LE_LINK)
1554 l2cap_le_conn_ready(conn);
1555
1556 queue_work(hcon->hdev->workqueue, &conn->pending_rx_work);
1557 }
1558
1559 /* Notify sockets that we cannot guaranty reliability anymore */
1560 static void l2cap_conn_unreliable(struct l2cap_conn *conn, int err)
1561 {
1562 struct l2cap_chan *chan;
1563
1564 BT_DBG("conn %p", conn);
1565
1566 mutex_lock(&conn->chan_lock);
1567
1568 list_for_each_entry(chan, &conn->chan_l, list) {
1569 if (test_bit(FLAG_FORCE_RELIABLE, &chan->flags))
1570 l2cap_chan_set_err(chan, err);
1571 }
1572
1573 mutex_unlock(&conn->chan_lock);
1574 }
1575
1576 static void l2cap_info_timeout(struct work_struct *work)
1577 {
1578 struct l2cap_conn *conn = container_of(work, struct l2cap_conn,
1579 info_timer.work);
1580
1581 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
1582 conn->info_ident = 0;
1583
1584 l2cap_conn_start(conn);
1585 }
1586
1587 /*
1588 * l2cap_user
1589 * External modules can register l2cap_user objects on l2cap_conn. The ->probe
1590 * callback is called during registration. The ->remove callback is called
1591 * during unregistration.
1592 * An l2cap_user object can either be explicitly unregistered or when the
1593 * underlying l2cap_conn object is deleted. This guarantees that l2cap->hcon,
1594 * l2cap->hchan, .. are valid as long as the remove callback hasn't been called.
1595 * External modules must own a reference to the l2cap_conn object if they intend
1596 * to call l2cap_unregister_user(). The l2cap_conn object might get destroyed at
1597 * any time if they don't.
1598 */
1599
1600 int l2cap_register_user(struct l2cap_conn *conn, struct l2cap_user *user)
1601 {
1602 struct hci_dev *hdev = conn->hcon->hdev;
1603 int ret;
1604
1605 /* We need to check whether l2cap_conn is registered. If it is not, we
1606 * must not register the l2cap_user. l2cap_conn_del() is unregisters
1607 * l2cap_conn objects, but doesn't provide its own locking. Instead, it
1608 * relies on the parent hci_conn object to be locked. This itself relies
1609 * on the hci_dev object to be locked. So we must lock the hci device
1610 * here, too. */
1611
1612 hci_dev_lock(hdev);
1613
1614 if (!list_empty(&user->list)) {
1615 ret = -EINVAL;
1616 goto out_unlock;
1617 }
1618
1619 /* conn->hchan is NULL after l2cap_conn_del() was called */
1620 if (!conn->hchan) {
1621 ret = -ENODEV;
1622 goto out_unlock;
1623 }
1624
1625 ret = user->probe(conn, user);
1626 if (ret)
1627 goto out_unlock;
1628
1629 list_add(&user->list, &conn->users);
1630 ret = 0;
1631
1632 out_unlock:
1633 hci_dev_unlock(hdev);
1634 return ret;
1635 }
1636 EXPORT_SYMBOL(l2cap_register_user);
1637
1638 void l2cap_unregister_user(struct l2cap_conn *conn, struct l2cap_user *user)
1639 {
1640 struct hci_dev *hdev = conn->hcon->hdev;
1641
1642 hci_dev_lock(hdev);
1643
1644 if (list_empty(&user->list))
1645 goto out_unlock;
1646
1647 list_del_init(&user->list);
1648 user->remove(conn, user);
1649
1650 out_unlock:
1651 hci_dev_unlock(hdev);
1652 }
1653 EXPORT_SYMBOL(l2cap_unregister_user);
1654
1655 static void l2cap_unregister_all_users(struct l2cap_conn *conn)
1656 {
1657 struct l2cap_user *user;
1658
1659 while (!list_empty(&conn->users)) {
1660 user = list_first_entry(&conn->users, struct l2cap_user, list);
1661 list_del_init(&user->list);
1662 user->remove(conn, user);
1663 }
1664 }
1665
1666 static void l2cap_conn_del(struct hci_conn *hcon, int err)
1667 {
1668 struct l2cap_conn *conn = hcon->l2cap_data;
1669 struct l2cap_chan *chan, *l;
1670
1671 if (!conn)
1672 return;
1673
1674 BT_DBG("hcon %p conn %p, err %d", hcon, conn, err);
1675
1676 kfree_skb(conn->rx_skb);
1677
1678 skb_queue_purge(&conn->pending_rx);
1679
1680 /* We can not call flush_work(&conn->pending_rx_work) here since we
1681 * might block if we are running on a worker from the same workqueue
1682 * pending_rx_work is waiting on.
1683 */
1684 if (work_pending(&conn->pending_rx_work))
1685 cancel_work_sync(&conn->pending_rx_work);
1686
1687 if (work_pending(&conn->id_addr_update_work))
1688 cancel_work_sync(&conn->id_addr_update_work);
1689
1690 l2cap_unregister_all_users(conn);
1691
1692 /* Force the connection to be immediately dropped */
1693 hcon->disc_timeout = 0;
1694
1695 mutex_lock(&conn->chan_lock);
1696
1697 /* Kill channels */
1698 list_for_each_entry_safe(chan, l, &conn->chan_l, list) {
1699 l2cap_chan_hold(chan);
1700 l2cap_chan_lock(chan);
1701
1702 l2cap_chan_del(chan, err);
1703
1704 l2cap_chan_unlock(chan);
1705
1706 chan->ops->close(chan);
1707 l2cap_chan_put(chan);
1708 }
1709
1710 mutex_unlock(&conn->chan_lock);
1711
1712 hci_chan_del(conn->hchan);
1713
1714 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT)
1715 cancel_delayed_work_sync(&conn->info_timer);
1716
1717 hcon->l2cap_data = NULL;
1718 conn->hchan = NULL;
1719 l2cap_conn_put(conn);
1720 }
1721
1722 static void l2cap_conn_free(struct kref *ref)
1723 {
1724 struct l2cap_conn *conn = container_of(ref, struct l2cap_conn, ref);
1725
1726 hci_conn_put(conn->hcon);
1727 kfree(conn);
1728 }
1729
1730 struct l2cap_conn *l2cap_conn_get(struct l2cap_conn *conn)
1731 {
1732 kref_get(&conn->ref);
1733 return conn;
1734 }
1735 EXPORT_SYMBOL(l2cap_conn_get);
1736
1737 void l2cap_conn_put(struct l2cap_conn *conn)
1738 {
1739 kref_put(&conn->ref, l2cap_conn_free);
1740 }
1741 EXPORT_SYMBOL(l2cap_conn_put);
1742
1743 /* ---- Socket interface ---- */
1744
1745 /* Find socket with psm and source / destination bdaddr.
1746 * Returns closest match.
1747 */
1748 static struct l2cap_chan *l2cap_global_chan_by_psm(int state, __le16 psm,
1749 bdaddr_t *src,
1750 bdaddr_t *dst,
1751 u8 link_type)
1752 {
1753 struct l2cap_chan *c, *c1 = NULL;
1754
1755 read_lock(&chan_list_lock);
1756
1757 list_for_each_entry(c, &chan_list, global_l) {
1758 if (state && c->state != state)
1759 continue;
1760
1761 if (link_type == ACL_LINK && c->src_type != BDADDR_BREDR)
1762 continue;
1763
1764 if (link_type == LE_LINK && c->src_type == BDADDR_BREDR)
1765 continue;
1766
1767 if (c->psm == psm) {
1768 int src_match, dst_match;
1769 int src_any, dst_any;
1770
1771 /* Exact match. */
1772 src_match = !bacmp(&c->src, src);
1773 dst_match = !bacmp(&c->dst, dst);
1774 if (src_match && dst_match) {
1775 l2cap_chan_hold(c);
1776 read_unlock(&chan_list_lock);
1777 return c;
1778 }
1779
1780 /* Closest match */
1781 src_any = !bacmp(&c->src, BDADDR_ANY);
1782 dst_any = !bacmp(&c->dst, BDADDR_ANY);
1783 if ((src_match && dst_any) || (src_any && dst_match) ||
1784 (src_any && dst_any))
1785 c1 = c;
1786 }
1787 }
1788
1789 if (c1)
1790 l2cap_chan_hold(c1);
1791
1792 read_unlock(&chan_list_lock);
1793
1794 return c1;
1795 }
1796
1797 static void l2cap_monitor_timeout(struct work_struct *work)
1798 {
1799 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
1800 monitor_timer.work);
1801
1802 BT_DBG("chan %p", chan);
1803
1804 l2cap_chan_lock(chan);
1805
1806 if (!chan->conn) {
1807 l2cap_chan_unlock(chan);
1808 l2cap_chan_put(chan);
1809 return;
1810 }
1811
1812 l2cap_tx(chan, NULL, NULL, L2CAP_EV_MONITOR_TO);
1813
1814 l2cap_chan_unlock(chan);
1815 l2cap_chan_put(chan);
1816 }
1817
1818 static void l2cap_retrans_timeout(struct work_struct *work)
1819 {
1820 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
1821 retrans_timer.work);
1822
1823 BT_DBG("chan %p", chan);
1824
1825 l2cap_chan_lock(chan);
1826
1827 if (!chan->conn) {
1828 l2cap_chan_unlock(chan);
1829 l2cap_chan_put(chan);
1830 return;
1831 }
1832
1833 l2cap_tx(chan, NULL, NULL, L2CAP_EV_RETRANS_TO);
1834 l2cap_chan_unlock(chan);
1835 l2cap_chan_put(chan);
1836 }
1837
1838 static void l2cap_streaming_send(struct l2cap_chan *chan,
1839 struct sk_buff_head *skbs)
1840 {
1841 struct sk_buff *skb;
1842 struct l2cap_ctrl *control;
1843
1844 BT_DBG("chan %p, skbs %p", chan, skbs);
1845
1846 if (__chan_is_moving(chan))
1847 return;
1848
1849 skb_queue_splice_tail_init(skbs, &chan->tx_q);
1850
1851 while (!skb_queue_empty(&chan->tx_q)) {
1852
1853 skb = skb_dequeue(&chan->tx_q);
1854
1855 bt_cb(skb)->l2cap.retries = 1;
1856 control = &bt_cb(skb)->l2cap;
1857
1858 control->reqseq = 0;
1859 control->txseq = chan->next_tx_seq;
1860
1861 __pack_control(chan, control, skb);
1862
1863 if (chan->fcs == L2CAP_FCS_CRC16) {
1864 u16 fcs = crc16(0, (u8 *) skb->data, skb->len);
1865 put_unaligned_le16(fcs, skb_put(skb, L2CAP_FCS_SIZE));
1866 }
1867
1868 l2cap_do_send(chan, skb);
1869
1870 BT_DBG("Sent txseq %u", control->txseq);
1871
1872 chan->next_tx_seq = __next_seq(chan, chan->next_tx_seq);
1873 chan->frames_sent++;
1874 }
1875 }
1876
1877 static int l2cap_ertm_send(struct l2cap_chan *chan)
1878 {
1879 struct sk_buff *skb, *tx_skb;
1880 struct l2cap_ctrl *control;
1881 int sent = 0;
1882
1883 BT_DBG("chan %p", chan);
1884
1885 if (chan->state != BT_CONNECTED)
1886 return -ENOTCONN;
1887
1888 if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state))
1889 return 0;
1890
1891 if (__chan_is_moving(chan))
1892 return 0;
1893
1894 while (chan->tx_send_head &&
1895 chan->unacked_frames < chan->remote_tx_win &&
1896 chan->tx_state == L2CAP_TX_STATE_XMIT) {
1897
1898 skb = chan->tx_send_head;
1899
1900 bt_cb(skb)->l2cap.retries = 1;
1901 control = &bt_cb(skb)->l2cap;
1902
1903 if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state))
1904 control->final = 1;
1905
1906 control->reqseq = chan->buffer_seq;
1907 chan->last_acked_seq = chan->buffer_seq;
1908 control->txseq = chan->next_tx_seq;
1909
1910 __pack_control(chan, control, skb);
1911
1912 if (chan->fcs == L2CAP_FCS_CRC16) {
1913 u16 fcs = crc16(0, (u8 *) skb->data, skb->len);
1914 put_unaligned_le16(fcs, skb_put(skb, L2CAP_FCS_SIZE));
1915 }
1916
1917 /* Clone after data has been modified. Data is assumed to be
1918 read-only (for locking purposes) on cloned sk_buffs.
1919 */
1920 tx_skb = skb_clone(skb, GFP_KERNEL);
1921
1922 if (!tx_skb)
1923 break;
1924
1925 __set_retrans_timer(chan);
1926
1927 chan->next_tx_seq = __next_seq(chan, chan->next_tx_seq);
1928 chan->unacked_frames++;
1929 chan->frames_sent++;
1930 sent++;
1931
1932 if (skb_queue_is_last(&chan->tx_q, skb))
1933 chan->tx_send_head = NULL;
1934 else
1935 chan->tx_send_head = skb_queue_next(&chan->tx_q, skb);
1936
1937 l2cap_do_send(chan, tx_skb);
1938 BT_DBG("Sent txseq %u", control->txseq);
1939 }
1940
1941 BT_DBG("Sent %d, %u unacked, %u in ERTM queue", sent,
1942 chan->unacked_frames, skb_queue_len(&chan->tx_q));
1943
1944 return sent;
1945 }
1946
1947 static void l2cap_ertm_resend(struct l2cap_chan *chan)
1948 {
1949 struct l2cap_ctrl control;
1950 struct sk_buff *skb;
1951 struct sk_buff *tx_skb;
1952 u16 seq;
1953
1954 BT_DBG("chan %p", chan);
1955
1956 if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state))
1957 return;
1958
1959 if (__chan_is_moving(chan))
1960 return;
1961
1962 while (chan->retrans_list.head != L2CAP_SEQ_LIST_CLEAR) {
1963 seq = l2cap_seq_list_pop(&chan->retrans_list);
1964
1965 skb = l2cap_ertm_seq_in_queue(&chan->tx_q, seq);
1966 if (!skb) {
1967 BT_DBG("Error: Can't retransmit seq %d, frame missing",
1968 seq);
1969 continue;
1970 }
1971
1972 bt_cb(skb)->l2cap.retries++;
1973 control = bt_cb(skb)->l2cap;
1974
1975 if (chan->max_tx != 0 &&
1976 bt_cb(skb)->l2cap.retries > chan->max_tx) {
1977 BT_DBG("Retry limit exceeded (%d)", chan->max_tx);
1978 l2cap_send_disconn_req(chan, ECONNRESET);
1979 l2cap_seq_list_clear(&chan->retrans_list);
1980 break;
1981 }
1982
1983 control.reqseq = chan->buffer_seq;
1984 if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state))
1985 control.final = 1;
1986 else
1987 control.final = 0;
1988
1989 if (skb_cloned(skb)) {
1990 /* Cloned sk_buffs are read-only, so we need a
1991 * writeable copy
1992 */
1993 tx_skb = skb_copy(skb, GFP_KERNEL);
1994 } else {
1995 tx_skb = skb_clone(skb, GFP_KERNEL);
1996 }
1997
1998 if (!tx_skb) {
1999 l2cap_seq_list_clear(&chan->retrans_list);
2000 break;
2001 }
2002
2003 /* Update skb contents */
2004 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) {
2005 put_unaligned_le32(__pack_extended_control(&control),
2006 tx_skb->data + L2CAP_HDR_SIZE);
2007 } else {
2008 put_unaligned_le16(__pack_enhanced_control(&control),
2009 tx_skb->data + L2CAP_HDR_SIZE);
2010 }
2011
2012 /* Update FCS */
2013 if (chan->fcs == L2CAP_FCS_CRC16) {
2014 u16 fcs = crc16(0, (u8 *) tx_skb->data,
2015 tx_skb->len - L2CAP_FCS_SIZE);
2016 put_unaligned_le16(fcs, skb_tail_pointer(tx_skb) -
2017 L2CAP_FCS_SIZE);
2018 }
2019
2020 l2cap_do_send(chan, tx_skb);
2021
2022 BT_DBG("Resent txseq %d", control.txseq);
2023
2024 chan->last_acked_seq = chan->buffer_seq;
2025 }
2026 }
2027
2028 static void l2cap_retransmit(struct l2cap_chan *chan,
2029 struct l2cap_ctrl *control)
2030 {
2031 BT_DBG("chan %p, control %p", chan, control);
2032
2033 l2cap_seq_list_append(&chan->retrans_list, control->reqseq);
2034 l2cap_ertm_resend(chan);
2035 }
2036
2037 static void l2cap_retransmit_all(struct l2cap_chan *chan,
2038 struct l2cap_ctrl *control)
2039 {
2040 struct sk_buff *skb;
2041
2042 BT_DBG("chan %p, control %p", chan, control);
2043
2044 if (control->poll)
2045 set_bit(CONN_SEND_FBIT, &chan->conn_state);
2046
2047 l2cap_seq_list_clear(&chan->retrans_list);
2048
2049 if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state))
2050 return;
2051
2052 if (chan->unacked_frames) {
2053 skb_queue_walk(&chan->tx_q, skb) {
2054 if (bt_cb(skb)->l2cap.txseq == control->reqseq ||
2055 skb == chan->tx_send_head)
2056 break;
2057 }
2058
2059 skb_queue_walk_from(&chan->tx_q, skb) {
2060 if (skb == chan->tx_send_head)
2061 break;
2062
2063 l2cap_seq_list_append(&chan->retrans_list,
2064 bt_cb(skb)->l2cap.txseq);
2065 }
2066
2067 l2cap_ertm_resend(chan);
2068 }
2069 }
2070
2071 static void l2cap_send_ack(struct l2cap_chan *chan)
2072 {
2073 struct l2cap_ctrl control;
2074 u16 frames_to_ack = __seq_offset(chan, chan->buffer_seq,
2075 chan->last_acked_seq);
2076 int threshold;
2077
2078 BT_DBG("chan %p last_acked_seq %d buffer_seq %d",
2079 chan, chan->last_acked_seq, chan->buffer_seq);
2080
2081 memset(&control, 0, sizeof(control));
2082 control.sframe = 1;
2083
2084 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state) &&
2085 chan->rx_state == L2CAP_RX_STATE_RECV) {
2086 __clear_ack_timer(chan);
2087 control.super = L2CAP_SUPER_RNR;
2088 control.reqseq = chan->buffer_seq;
2089 l2cap_send_sframe(chan, &control);
2090 } else {
2091 if (!test_bit(CONN_REMOTE_BUSY, &chan->conn_state)) {
2092 l2cap_ertm_send(chan);
2093 /* If any i-frames were sent, they included an ack */
2094 if (chan->buffer_seq == chan->last_acked_seq)
2095 frames_to_ack = 0;
2096 }
2097
2098 /* Ack now if the window is 3/4ths full.
2099 * Calculate without mul or div
2100 */
2101 threshold = chan->ack_win;
2102 threshold += threshold << 1;
2103 threshold >>= 2;
2104
2105 BT_DBG("frames_to_ack %u, threshold %d", frames_to_ack,
2106 threshold);
2107
2108 if (frames_to_ack >= threshold) {
2109 __clear_ack_timer(chan);
2110 control.super = L2CAP_SUPER_RR;
2111 control.reqseq = chan->buffer_seq;
2112 l2cap_send_sframe(chan, &control);
2113 frames_to_ack = 0;
2114 }
2115
2116 if (frames_to_ack)
2117 __set_ack_timer(chan);
2118 }
2119 }
2120
2121 static inline int l2cap_skbuff_fromiovec(struct l2cap_chan *chan,
2122 struct msghdr *msg, int len,
2123 int count, struct sk_buff *skb)
2124 {
2125 struct l2cap_conn *conn = chan->conn;
2126 struct sk_buff **frag;
2127 int sent = 0;
2128
2129 if (copy_from_iter(skb_put(skb, count), count, &msg->msg_iter) != count)
2130 return -EFAULT;
2131
2132 sent += count;
2133 len -= count;
2134
2135 /* Continuation fragments (no L2CAP header) */
2136 frag = &skb_shinfo(skb)->frag_list;
2137 while (len) {
2138 struct sk_buff *tmp;
2139
2140 count = min_t(unsigned int, conn->mtu, len);
2141
2142 tmp = chan->ops->alloc_skb(chan, 0, count,
2143 msg->msg_flags & MSG_DONTWAIT);
2144 if (IS_ERR(tmp))
2145 return PTR_ERR(tmp);
2146
2147 *frag = tmp;
2148
2149 if (copy_from_iter(skb_put(*frag, count), count,
2150 &msg->msg_iter) != count)
2151 return -EFAULT;
2152
2153 sent += count;
2154 len -= count;
2155
2156 skb->len += (*frag)->len;
2157 skb->data_len += (*frag)->len;
2158
2159 frag = &(*frag)->next;
2160 }
2161
2162 return sent;
2163 }
2164
2165 static struct sk_buff *l2cap_create_connless_pdu(struct l2cap_chan *chan,
2166 struct msghdr *msg, size_t len)
2167 {
2168 struct l2cap_conn *conn = chan->conn;
2169 struct sk_buff *skb;
2170 int err, count, hlen = L2CAP_HDR_SIZE + L2CAP_PSMLEN_SIZE;
2171 struct l2cap_hdr *lh;
2172
2173 BT_DBG("chan %p psm 0x%2.2x len %zu", chan,
2174 __le16_to_cpu(chan->psm), len);
2175
2176 count = min_t(unsigned int, (conn->mtu - hlen), len);
2177
2178 skb = chan->ops->alloc_skb(chan, hlen, count,
2179 msg->msg_flags & MSG_DONTWAIT);
2180 if (IS_ERR(skb))
2181 return skb;
2182
2183 /* Create L2CAP header */
2184 lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
2185 lh->cid = cpu_to_le16(chan->dcid);
2186 lh->len = cpu_to_le16(len + L2CAP_PSMLEN_SIZE);
2187 put_unaligned(chan->psm, (__le16 *) skb_put(skb, L2CAP_PSMLEN_SIZE));
2188
2189 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2190 if (unlikely(err < 0)) {
2191 kfree_skb(skb);
2192 return ERR_PTR(err);
2193 }
2194 return skb;
2195 }
2196
2197 static struct sk_buff *l2cap_create_basic_pdu(struct l2cap_chan *chan,
2198 struct msghdr *msg, size_t len)
2199 {
2200 struct l2cap_conn *conn = chan->conn;
2201 struct sk_buff *skb;
2202 int err, count;
2203 struct l2cap_hdr *lh;
2204
2205 BT_DBG("chan %p len %zu", chan, len);
2206
2207 count = min_t(unsigned int, (conn->mtu - L2CAP_HDR_SIZE), len);
2208
2209 skb = chan->ops->alloc_skb(chan, L2CAP_HDR_SIZE, count,
2210 msg->msg_flags & MSG_DONTWAIT);
2211 if (IS_ERR(skb))
2212 return skb;
2213
2214 /* Create L2CAP header */
2215 lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
2216 lh->cid = cpu_to_le16(chan->dcid);
2217 lh->len = cpu_to_le16(len);
2218
2219 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2220 if (unlikely(err < 0)) {
2221 kfree_skb(skb);
2222 return ERR_PTR(err);
2223 }
2224 return skb;
2225 }
2226
2227 static struct sk_buff *l2cap_create_iframe_pdu(struct l2cap_chan *chan,
2228 struct msghdr *msg, size_t len,
2229 u16 sdulen)
2230 {
2231 struct l2cap_conn *conn = chan->conn;
2232 struct sk_buff *skb;
2233 int err, count, hlen;
2234 struct l2cap_hdr *lh;
2235
2236 BT_DBG("chan %p len %zu", chan, len);
2237
2238 if (!conn)
2239 return ERR_PTR(-ENOTCONN);
2240
2241 hlen = __ertm_hdr_size(chan);
2242
2243 if (sdulen)
2244 hlen += L2CAP_SDULEN_SIZE;
2245
2246 if (chan->fcs == L2CAP_FCS_CRC16)
2247 hlen += L2CAP_FCS_SIZE;
2248
2249 count = min_t(unsigned int, (conn->mtu - hlen), len);
2250
2251 skb = chan->ops->alloc_skb(chan, hlen, count,
2252 msg->msg_flags & MSG_DONTWAIT);
2253 if (IS_ERR(skb))
2254 return skb;
2255
2256 /* Create L2CAP header */
2257 lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
2258 lh->cid = cpu_to_le16(chan->dcid);
2259 lh->len = cpu_to_le16(len + (hlen - L2CAP_HDR_SIZE));
2260
2261 /* Control header is populated later */
2262 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
2263 put_unaligned_le32(0, skb_put(skb, L2CAP_EXT_CTRL_SIZE));
2264 else
2265 put_unaligned_le16(0, skb_put(skb, L2CAP_ENH_CTRL_SIZE));
2266
2267 if (sdulen)
2268 put_unaligned_le16(sdulen, skb_put(skb, L2CAP_SDULEN_SIZE));
2269
2270 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2271 if (unlikely(err < 0)) {
2272 kfree_skb(skb);
2273 return ERR_PTR(err);
2274 }
2275
2276 bt_cb(skb)->l2cap.fcs = chan->fcs;
2277 bt_cb(skb)->l2cap.retries = 0;
2278 return skb;
2279 }
2280
2281 static int l2cap_segment_sdu(struct l2cap_chan *chan,
2282 struct sk_buff_head *seg_queue,
2283 struct msghdr *msg, size_t len)
2284 {
2285 struct sk_buff *skb;
2286 u16 sdu_len;
2287 size_t pdu_len;
2288 u8 sar;
2289
2290 BT_DBG("chan %p, msg %p, len %zu", chan, msg, len);
2291
2292 /* It is critical that ERTM PDUs fit in a single HCI fragment,
2293 * so fragmented skbs are not used. The HCI layer's handling
2294 * of fragmented skbs is not compatible with ERTM's queueing.
2295 */
2296
2297 /* PDU size is derived from the HCI MTU */
2298 pdu_len = chan->conn->mtu;
2299
2300 /* Constrain PDU size for BR/EDR connections */
2301 if (!chan->hs_hcon)
2302 pdu_len = min_t(size_t, pdu_len, L2CAP_BREDR_MAX_PAYLOAD);
2303
2304 /* Adjust for largest possible L2CAP overhead. */
2305 if (chan->fcs)
2306 pdu_len -= L2CAP_FCS_SIZE;
2307
2308 pdu_len -= __ertm_hdr_size(chan);
2309
2310 /* Remote device may have requested smaller PDUs */
2311 pdu_len = min_t(size_t, pdu_len, chan->remote_mps);
2312
2313 if (len <= pdu_len) {
2314 sar = L2CAP_SAR_UNSEGMENTED;
2315 sdu_len = 0;
2316 pdu_len = len;
2317 } else {
2318 sar = L2CAP_SAR_START;
2319 sdu_len = len;
2320 }
2321
2322 while (len > 0) {
2323 skb = l2cap_create_iframe_pdu(chan, msg, pdu_len, sdu_len);
2324
2325 if (IS_ERR(skb)) {
2326 __skb_queue_purge(seg_queue);
2327 return PTR_ERR(skb);
2328 }
2329
2330 bt_cb(skb)->l2cap.sar = sar;
2331 __skb_queue_tail(seg_queue, skb);
2332
2333 len -= pdu_len;
2334 if (sdu_len)
2335 sdu_len = 0;
2336
2337 if (len <= pdu_len) {
2338 sar = L2CAP_SAR_END;
2339 pdu_len = len;
2340 } else {
2341 sar = L2CAP_SAR_CONTINUE;
2342 }
2343 }
2344
2345 return 0;
2346 }
2347
2348 static struct sk_buff *l2cap_create_le_flowctl_pdu(struct l2cap_chan *chan,
2349 struct msghdr *msg,
2350 size_t len, u16 sdulen)
2351 {
2352 struct l2cap_conn *conn = chan->conn;
2353 struct sk_buff *skb;
2354 int err, count, hlen;
2355 struct l2cap_hdr *lh;
2356
2357 BT_DBG("chan %p len %zu", chan, len);
2358
2359 if (!conn)
2360 return ERR_PTR(-ENOTCONN);
2361
2362 hlen = L2CAP_HDR_SIZE;
2363
2364 if (sdulen)
2365 hlen += L2CAP_SDULEN_SIZE;
2366
2367 count = min_t(unsigned int, (conn->mtu - hlen), len);
2368
2369 skb = chan->ops->alloc_skb(chan, hlen, count,
2370 msg->msg_flags & MSG_DONTWAIT);
2371 if (IS_ERR(skb))
2372 return skb;
2373
2374 /* Create L2CAP header */
2375 lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
2376 lh->cid = cpu_to_le16(chan->dcid);
2377 lh->len = cpu_to_le16(len + (hlen - L2CAP_HDR_SIZE));
2378
2379 if (sdulen)
2380 put_unaligned_le16(sdulen, skb_put(skb, L2CAP_SDULEN_SIZE));
2381
2382 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2383 if (unlikely(err < 0)) {
2384 kfree_skb(skb);
2385 return ERR_PTR(err);
2386 }
2387
2388 return skb;
2389 }
2390
2391 static int l2cap_segment_le_sdu(struct l2cap_chan *chan,
2392 struct sk_buff_head *seg_queue,
2393 struct msghdr *msg, size_t len)
2394 {
2395 struct sk_buff *skb;
2396 size_t pdu_len;
2397 u16 sdu_len;
2398
2399 BT_DBG("chan %p, msg %p, len %zu", chan, msg, len);
2400
2401 sdu_len = len;
2402 pdu_len = chan->remote_mps - L2CAP_SDULEN_SIZE;
2403
2404 while (len > 0) {
2405 if (len <= pdu_len)
2406 pdu_len = len;
2407
2408 skb = l2cap_create_le_flowctl_pdu(chan, msg, pdu_len, sdu_len);
2409 if (IS_ERR(skb)) {
2410 __skb_queue_purge(seg_queue);
2411 return PTR_ERR(skb);
2412 }
2413
2414 __skb_queue_tail(seg_queue, skb);
2415
2416 len -= pdu_len;
2417
2418 if (sdu_len) {
2419 sdu_len = 0;
2420 pdu_len += L2CAP_SDULEN_SIZE;
2421 }
2422 }
2423
2424 return 0;
2425 }
2426
2427 int l2cap_chan_send(struct l2cap_chan *chan, struct msghdr *msg, size_t len)
2428 {
2429 struct sk_buff *skb;
2430 int err;
2431 struct sk_buff_head seg_queue;
2432
2433 if (!chan->conn)
2434 return -ENOTCONN;
2435
2436 /* Connectionless channel */
2437 if (chan->chan_type == L2CAP_CHAN_CONN_LESS) {
2438 skb = l2cap_create_connless_pdu(chan, msg, len);
2439 if (IS_ERR(skb))
2440 return PTR_ERR(skb);
2441
2442 /* Channel lock is released before requesting new skb and then
2443 * reacquired thus we need to recheck channel state.
2444 */
2445 if (chan->state != BT_CONNECTED) {
2446 kfree_skb(skb);
2447 return -ENOTCONN;
2448 }
2449
2450 l2cap_do_send(chan, skb);
2451 return len;
2452 }
2453
2454 switch (chan->mode) {
2455 case L2CAP_MODE_LE_FLOWCTL:
2456 /* Check outgoing MTU */
2457 if (len > chan->omtu)
2458 return -EMSGSIZE;
2459
2460 if (!chan->tx_credits)
2461 return -EAGAIN;
2462
2463 __skb_queue_head_init(&seg_queue);
2464
2465 err = l2cap_segment_le_sdu(chan, &seg_queue, msg, len);
2466
2467 if (chan->state != BT_CONNECTED) {
2468 __skb_queue_purge(&seg_queue);
2469 err = -ENOTCONN;
2470 }
2471
2472 if (err)
2473 return err;
2474
2475 skb_queue_splice_tail_init(&seg_queue, &chan->tx_q);
2476
2477 while (chan->tx_credits && !skb_queue_empty(&chan->tx_q)) {
2478 l2cap_do_send(chan, skb_dequeue(&chan->tx_q));
2479 chan->tx_credits--;
2480 }
2481
2482 if (!chan->tx_credits)
2483 chan->ops->suspend(chan);
2484
2485 err = len;
2486
2487 break;
2488
2489 case L2CAP_MODE_BASIC:
2490 /* Check outgoing MTU */
2491 if (len > chan->omtu)
2492 return -EMSGSIZE;
2493
2494 /* Create a basic PDU */
2495 skb = l2cap_create_basic_pdu(chan, msg, len);
2496 if (IS_ERR(skb))
2497 return PTR_ERR(skb);
2498
2499 /* Channel lock is released before requesting new skb and then
2500 * reacquired thus we need to recheck channel state.
2501 */
2502 if (chan->state != BT_CONNECTED) {
2503 kfree_skb(skb);
2504 return -ENOTCONN;
2505 }
2506
2507 l2cap_do_send(chan, skb);
2508 err = len;
2509 break;
2510
2511 case L2CAP_MODE_ERTM:
2512 case L2CAP_MODE_STREAMING:
2513 /* Check outgoing MTU */
2514 if (len > chan->omtu) {
2515 err = -EMSGSIZE;
2516 break;
2517 }
2518
2519 __skb_queue_head_init(&seg_queue);
2520
2521 /* Do segmentation before calling in to the state machine,
2522 * since it's possible to block while waiting for memory
2523 * allocation.
2524 */
2525 err = l2cap_segment_sdu(chan, &seg_queue, msg, len);
2526
2527 /* The channel could have been closed while segmenting,
2528 * check that it is still connected.
2529 */
2530 if (chan->state != BT_CONNECTED) {
2531 __skb_queue_purge(&seg_queue);
2532 err = -ENOTCONN;
2533 }
2534
2535 if (err)
2536 break;
2537
2538 if (chan->mode == L2CAP_MODE_ERTM)
2539 l2cap_tx(chan, NULL, &seg_queue, L2CAP_EV_DATA_REQUEST);
2540 else
2541 l2cap_streaming_send(chan, &seg_queue);
2542
2543 err = len;
2544
2545 /* If the skbs were not queued for sending, they'll still be in
2546 * seg_queue and need to be purged.
2547 */
2548 __skb_queue_purge(&seg_queue);
2549 break;
2550
2551 default:
2552 BT_DBG("bad state %1.1x", chan->mode);
2553 err = -EBADFD;
2554 }
2555
2556 return err;
2557 }
2558 EXPORT_SYMBOL_GPL(l2cap_chan_send);
2559
2560 static void l2cap_send_srej(struct l2cap_chan *chan, u16 txseq)
2561 {
2562 struct l2cap_ctrl control;
2563 u16 seq;
2564
2565 BT_DBG("chan %p, txseq %u", chan, txseq);
2566
2567 memset(&control, 0, sizeof(control));
2568 control.sframe = 1;
2569 control.super = L2CAP_SUPER_SREJ;
2570
2571 for (seq = chan->expected_tx_seq; seq != txseq;
2572 seq = __next_seq(chan, seq)) {
2573 if (!l2cap_ertm_seq_in_queue(&chan->srej_q, seq)) {
2574 control.reqseq = seq;
2575 l2cap_send_sframe(chan, &control);
2576 l2cap_seq_list_append(&chan->srej_list, seq);
2577 }
2578 }
2579
2580 chan->expected_tx_seq = __next_seq(chan, txseq);
2581 }
2582
2583 static void l2cap_send_srej_tail(struct l2cap_chan *chan)
2584 {
2585 struct l2cap_ctrl control;
2586
2587 BT_DBG("chan %p", chan);
2588
2589 if (chan->srej_list.tail == L2CAP_SEQ_LIST_CLEAR)
2590 return;
2591
2592 memset(&control, 0, sizeof(control));
2593 control.sframe = 1;
2594 control.super = L2CAP_SUPER_SREJ;
2595 control.reqseq = chan->srej_list.tail;
2596 l2cap_send_sframe(chan, &control);
2597 }
2598
2599 static void l2cap_send_srej_list(struct l2cap_chan *chan, u16 txseq)
2600 {
2601 struct l2cap_ctrl control;
2602 u16 initial_head;
2603 u16 seq;
2604
2605 BT_DBG("chan %p, txseq %u", chan, txseq);
2606
2607 memset(&control, 0, sizeof(control));
2608 control.sframe = 1;
2609 control.super = L2CAP_SUPER_SREJ;
2610
2611 /* Capture initial list head to allow only one pass through the list. */
2612 initial_head = chan->srej_list.head;
2613
2614 do {
2615 seq = l2cap_seq_list_pop(&chan->srej_list);
2616 if (seq == txseq || seq == L2CAP_SEQ_LIST_CLEAR)
2617 break;
2618
2619 control.reqseq = seq;
2620 l2cap_send_sframe(chan, &control);
2621 l2cap_seq_list_append(&chan->srej_list, seq);
2622 } while (chan->srej_list.head != initial_head);
2623 }
2624
2625 static void l2cap_process_reqseq(struct l2cap_chan *chan, u16 reqseq)
2626 {
2627 struct sk_buff *acked_skb;
2628 u16 ackseq;
2629
2630 BT_DBG("chan %p, reqseq %u", chan, reqseq);
2631
2632 if (chan->unacked_frames == 0 || reqseq == chan->expected_ack_seq)
2633 return;
2634
2635 BT_DBG("expected_ack_seq %u, unacked_frames %u",
2636 chan->expected_ack_seq, chan->unacked_frames);
2637
2638 for (ackseq = chan->expected_ack_seq; ackseq != reqseq;
2639 ackseq = __next_seq(chan, ackseq)) {
2640
2641 acked_skb = l2cap_ertm_seq_in_queue(&chan->tx_q, ackseq);
2642 if (acked_skb) {
2643 skb_unlink(acked_skb, &chan->tx_q);
2644 kfree_skb(acked_skb);
2645 chan->unacked_frames--;
2646 }
2647 }
2648
2649 chan->expected_ack_seq = reqseq;
2650
2651 if (chan->unacked_frames == 0)
2652 __clear_retrans_timer(chan);
2653
2654 BT_DBG("unacked_frames %u", chan->unacked_frames);
2655 }
2656
2657 static void l2cap_abort_rx_srej_sent(struct l2cap_chan *chan)
2658 {
2659 BT_DBG("chan %p", chan);
2660
2661 chan->expected_tx_seq = chan->buffer_seq;
2662 l2cap_seq_list_clear(&chan->srej_list);
2663 skb_queue_purge(&chan->srej_q);
2664 chan->rx_state = L2CAP_RX_STATE_RECV;
2665 }
2666
2667 static void l2cap_tx_state_xmit(struct l2cap_chan *chan,
2668 struct l2cap_ctrl *control,
2669 struct sk_buff_head *skbs, u8 event)
2670 {
2671 BT_DBG("chan %p, control %p, skbs %p, event %d", chan, control, skbs,
2672 event);
2673
2674 switch (event) {
2675 case L2CAP_EV_DATA_REQUEST:
2676 if (chan->tx_send_head == NULL)
2677 chan->tx_send_head = skb_peek(skbs);
2678
2679 skb_queue_splice_tail_init(skbs, &chan->tx_q);
2680 l2cap_ertm_send(chan);
2681 break;
2682 case L2CAP_EV_LOCAL_BUSY_DETECTED:
2683 BT_DBG("Enter LOCAL_BUSY");
2684 set_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2685
2686 if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) {
2687 /* The SREJ_SENT state must be aborted if we are to
2688 * enter the LOCAL_BUSY state.
2689 */
2690 l2cap_abort_rx_srej_sent(chan);
2691 }
2692
2693 l2cap_send_ack(chan);
2694
2695 break;
2696 case L2CAP_EV_LOCAL_BUSY_CLEAR:
2697 BT_DBG("Exit LOCAL_BUSY");
2698 clear_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2699
2700 if (test_bit(CONN_RNR_SENT, &chan->conn_state)) {
2701 struct l2cap_ctrl local_control;
2702
2703 memset(&local_control, 0, sizeof(local_control));
2704 local_control.sframe = 1;
2705 local_control.super = L2CAP_SUPER_RR;
2706 local_control.poll = 1;
2707 local_control.reqseq = chan->buffer_seq;
2708 l2cap_send_sframe(chan, &local_control);
2709
2710 chan->retry_count = 1;
2711 __set_monitor_timer(chan);
2712 chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2713 }
2714 break;
2715 case L2CAP_EV_RECV_REQSEQ_AND_FBIT:
2716 l2cap_process_reqseq(chan, control->reqseq);
2717 break;
2718 case L2CAP_EV_EXPLICIT_POLL:
2719 l2cap_send_rr_or_rnr(chan, 1);
2720 chan->retry_count = 1;
2721 __set_monitor_timer(chan);
2722 __clear_ack_timer(chan);
2723 chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2724 break;
2725 case L2CAP_EV_RETRANS_TO:
2726 l2cap_send_rr_or_rnr(chan, 1);
2727 chan->retry_count = 1;
2728 __set_monitor_timer(chan);
2729 chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2730 break;
2731 case L2CAP_EV_RECV_FBIT:
2732 /* Nothing to process */
2733 break;
2734 default:
2735 break;
2736 }
2737 }
2738
2739 static void l2cap_tx_state_wait_f(struct l2cap_chan *chan,
2740 struct l2cap_ctrl *control,
2741 struct sk_buff_head *skbs, u8 event)
2742 {
2743 BT_DBG("chan %p, control %p, skbs %p, event %d", chan, control, skbs,
2744 event);
2745
2746 switch (event) {
2747 case L2CAP_EV_DATA_REQUEST:
2748 if (chan->tx_send_head == NULL)
2749 chan->tx_send_head = skb_peek(skbs);
2750 /* Queue data, but don't send. */
2751 skb_queue_splice_tail_init(skbs, &chan->tx_q);
2752 break;
2753 case L2CAP_EV_LOCAL_BUSY_DETECTED:
2754 BT_DBG("Enter LOCAL_BUSY");
2755 set_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2756
2757 if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) {
2758 /* The SREJ_SENT state must be aborted if we are to
2759 * enter the LOCAL_BUSY state.
2760 */
2761 l2cap_abort_rx_srej_sent(chan);
2762 }
2763
2764 l2cap_send_ack(chan);
2765
2766 break;
2767 case L2CAP_EV_LOCAL_BUSY_CLEAR:
2768 BT_DBG("Exit LOCAL_BUSY");
2769 clear_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2770
2771 if (test_bit(CONN_RNR_SENT, &chan->conn_state)) {
2772 struct l2cap_ctrl local_control;
2773 memset(&local_control, 0, sizeof(local_control));
2774 local_control.sframe = 1;
2775 local_control.super = L2CAP_SUPER_RR;
2776 local_control.poll = 1;
2777 local_control.reqseq = chan->buffer_seq;
2778 l2cap_send_sframe(chan, &local_control);
2779
2780 chan->retry_count = 1;
2781 __set_monitor_timer(chan);
2782 chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2783 }
2784 break;
2785 case L2CAP_EV_RECV_REQSEQ_AND_FBIT:
2786 l2cap_process_reqseq(chan, control->reqseq);
2787
2788 /* Fall through */
2789
2790 case L2CAP_EV_RECV_FBIT:
2791 if (control && control->final) {
2792 __clear_monitor_timer(chan);
2793 if (chan->unacked_frames > 0)
2794 __set_retrans_timer(chan);
2795 chan->retry_count = 0;
2796 chan->tx_state = L2CAP_TX_STATE_XMIT;
2797 BT_DBG("recv fbit tx_state 0x2.2%x", chan->tx_state);
2798 }
2799 break;
2800 case L2CAP_EV_EXPLICIT_POLL:
2801 /* Ignore */
2802 break;
2803 case L2CAP_EV_MONITOR_TO:
2804 if (chan->max_tx == 0 || chan->retry_count < chan->max_tx) {
2805 l2cap_send_rr_or_rnr(chan, 1);
2806 __set_monitor_timer(chan);
2807 chan->retry_count++;
2808 } else {
2809 l2cap_send_disconn_req(chan, ECONNABORTED);
2810 }
2811 break;
2812 default:
2813 break;
2814 }
2815 }
2816
2817 static void l2cap_tx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
2818 struct sk_buff_head *skbs, u8 event)
2819 {
2820 BT_DBG("chan %p, control %p, skbs %p, event %d, state %d",
2821 chan, control, skbs, event, chan->tx_state);
2822
2823 switch (chan->tx_state) {
2824 case L2CAP_TX_STATE_XMIT:
2825 l2cap_tx_state_xmit(chan, control, skbs, event);
2826 break;
2827 case L2CAP_TX_STATE_WAIT_F:
2828 l2cap_tx_state_wait_f(chan, control, skbs, event);
2829 break;
2830 default:
2831 /* Ignore event */
2832 break;
2833 }
2834 }
2835
2836 static void l2cap_pass_to_tx(struct l2cap_chan *chan,
2837 struct l2cap_ctrl *control)
2838 {
2839 BT_DBG("chan %p, control %p", chan, control);
2840 l2cap_tx(chan, control, NULL, L2CAP_EV_RECV_REQSEQ_AND_FBIT);
2841 }
2842
2843 static void l2cap_pass_to_tx_fbit(struct l2cap_chan *chan,
2844 struct l2cap_ctrl *control)
2845 {
2846 BT_DBG("chan %p, control %p", chan, control);
2847 l2cap_tx(chan, control, NULL, L2CAP_EV_RECV_FBIT);
2848 }
2849
2850 /* Copy frame to all raw sockets on that connection */
2851 static void l2cap_raw_recv(struct l2cap_conn *conn, struct sk_buff *skb)
2852 {
2853 struct sk_buff *nskb;
2854 struct l2cap_chan *chan;
2855
2856 BT_DBG("conn %p", conn);
2857
2858 mutex_lock(&conn->chan_lock);
2859
2860 list_for_each_entry(chan, &conn->chan_l, list) {
2861 if (chan->chan_type != L2CAP_CHAN_RAW)
2862 continue;
2863
2864 /* Don't send frame to the channel it came from */
2865 if (bt_cb(skb)->l2cap.chan == chan)
2866 continue;
2867
2868 nskb = skb_clone(skb, GFP_KERNEL);
2869 if (!nskb)
2870 continue;
2871 if (chan->ops->recv(chan, nskb))
2872 kfree_skb(nskb);
2873 }
2874
2875 mutex_unlock(&conn->chan_lock);
2876 }
2877
2878 /* ---- L2CAP signalling commands ---- */
2879 static struct sk_buff *l2cap_build_cmd(struct l2cap_conn *conn, u8 code,
2880 u8 ident, u16 dlen, void *data)
2881 {
2882 struct sk_buff *skb, **frag;
2883 struct l2cap_cmd_hdr *cmd;
2884 struct l2cap_hdr *lh;
2885 int len, count;
2886
2887 BT_DBG("conn %p, code 0x%2.2x, ident 0x%2.2x, len %u",
2888 conn, code, ident, dlen);
2889
2890 if (conn->mtu < L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE)
2891 return NULL;
2892
2893 len = L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE + dlen;
2894 count = min_t(unsigned int, conn->mtu, len);
2895
2896 skb = bt_skb_alloc(count, GFP_KERNEL);
2897 if (!skb)
2898 return NULL;
2899
2900 lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
2901 lh->len = cpu_to_le16(L2CAP_CMD_HDR_SIZE + dlen);
2902
2903 if (conn->hcon->type == LE_LINK)
2904 lh->cid = cpu_to_le16(L2CAP_CID_LE_SIGNALING);
2905 else
2906 lh->cid = cpu_to_le16(L2CAP_CID_SIGNALING);
2907
2908 cmd = (struct l2cap_cmd_hdr *) skb_put(skb, L2CAP_CMD_HDR_SIZE);
2909 cmd->code = code;
2910 cmd->ident = ident;
2911 cmd->len = cpu_to_le16(dlen);
2912
2913 if (dlen) {
2914 count -= L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE;
2915 memcpy(skb_put(skb, count), data, count);
2916 data += count;
2917 }
2918
2919 len -= skb->len;
2920
2921 /* Continuation fragments (no L2CAP header) */
2922 frag = &skb_shinfo(skb)->frag_list;
2923 while (len) {
2924 count = min_t(unsigned int, conn->mtu, len);
2925
2926 *frag = bt_skb_alloc(count, GFP_KERNEL);
2927 if (!*frag)
2928 goto fail;
2929
2930 memcpy(skb_put(*frag, count), data, count);
2931
2932 len -= count;
2933 data += count;
2934
2935 frag = &(*frag)->next;
2936 }
2937
2938 return skb;
2939
2940 fail:
2941 kfree_skb(skb);
2942 return NULL;
2943 }
2944
2945 static inline int l2cap_get_conf_opt(void **ptr, int *type, int *olen,
2946 unsigned long *val)
2947 {
2948 struct l2cap_conf_opt *opt = *ptr;
2949 int len;
2950
2951 len = L2CAP_CONF_OPT_SIZE + opt->len;
2952 *ptr += len;
2953
2954 *type = opt->type;
2955 *olen = opt->len;
2956
2957 switch (opt->len) {
2958 case 1:
2959 *val = *((u8 *) opt->val);
2960 break;
2961
2962 case 2:
2963 *val = get_unaligned_le16(opt->val);
2964 break;
2965
2966 case 4:
2967 *val = get_unaligned_le32(opt->val);
2968 break;
2969
2970 default:
2971 *val = (unsigned long) opt->val;
2972 break;
2973 }
2974
2975 BT_DBG("type 0x%2.2x len %u val 0x%lx", *type, opt->len, *val);
2976 return len;
2977 }
2978
2979 static void l2cap_add_conf_opt(void **ptr, u8 type, u8 len, unsigned long val)
2980 {
2981 struct l2cap_conf_opt *opt = *ptr;
2982
2983 BT_DBG("type 0x%2.2x len %u val 0x%lx", type, len, val);
2984
2985 opt->type = type;
2986 opt->len = len;
2987
2988 switch (len) {
2989 case 1:
2990 *((u8 *) opt->val) = val;
2991 break;
2992
2993 case 2:
2994 put_unaligned_le16(val, opt->val);
2995 break;
2996
2997 case 4:
2998 put_unaligned_le32(val, opt->val);
2999 break;
3000
3001 default:
3002 memcpy(opt->val, (void *) val, len);
3003 break;
3004 }
3005
3006 *ptr += L2CAP_CONF_OPT_SIZE + len;
3007 }
3008
3009 static void l2cap_add_opt_efs(void **ptr, struct l2cap_chan *chan)
3010 {
3011 struct l2cap_conf_efs efs;
3012
3013 switch (chan->mode) {
3014 case L2CAP_MODE_ERTM:
3015 efs.id = chan->local_id;
3016 efs.stype = chan->local_stype;
3017 efs.msdu = cpu_to_le16(chan->local_msdu);
3018 efs.sdu_itime = cpu_to_le32(chan->local_sdu_itime);
3019 efs.acc_lat = cpu_to_le32(L2CAP_DEFAULT_ACC_LAT);
3020 efs.flush_to = cpu_to_le32(L2CAP_EFS_DEFAULT_FLUSH_TO);
3021 break;
3022
3023 case L2CAP_MODE_STREAMING:
3024 efs.id = 1;
3025 efs.stype = L2CAP_SERV_BESTEFFORT;
3026 efs.msdu = cpu_to_le16(chan->local_msdu);
3027 efs.sdu_itime = cpu_to_le32(chan->local_sdu_itime);
3028 efs.acc_lat = 0;
3029 efs.flush_to = 0;
3030 break;
3031
3032 default:
3033 return;
3034 }
3035
3036 l2cap_add_conf_opt(ptr, L2CAP_CONF_EFS, sizeof(efs),
3037 (unsigned long) &efs);
3038 }
3039
3040 static void l2cap_ack_timeout(struct work_struct *work)
3041 {
3042 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
3043 ack_timer.work);
3044 u16 frames_to_ack;
3045
3046 BT_DBG("chan %p", chan);
3047
3048 l2cap_chan_lock(chan);
3049
3050 frames_to_ack = __seq_offset(chan, chan->buffer_seq,
3051 chan->last_acked_seq);
3052
3053 if (frames_to_ack)
3054 l2cap_send_rr_or_rnr(chan, 0);
3055
3056 l2cap_chan_unlock(chan);
3057 l2cap_chan_put(chan);
3058 }
3059
3060 int l2cap_ertm_init(struct l2cap_chan *chan)
3061 {
3062 int err;
3063
3064 chan->next_tx_seq = 0;
3065 chan->expected_tx_seq = 0;
3066 chan->expected_ack_seq = 0;
3067 chan->unacked_frames = 0;
3068 chan->buffer_seq = 0;
3069 chan->frames_sent = 0;
3070 chan->last_acked_seq = 0;
3071 chan->sdu = NULL;
3072 chan->sdu_last_frag = NULL;
3073 chan->sdu_len = 0;
3074
3075 skb_queue_head_init(&chan->tx_q);
3076
3077 chan->local_amp_id = AMP_ID_BREDR;
3078 chan->move_id = AMP_ID_BREDR;
3079 chan->move_state = L2CAP_MOVE_STABLE;
3080 chan->move_role = L2CAP_MOVE_ROLE_NONE;
3081
3082 if (chan->mode != L2CAP_MODE_ERTM)
3083 return 0;
3084
3085 chan->rx_state = L2CAP_RX_STATE_RECV;
3086 chan->tx_state = L2CAP_TX_STATE_XMIT;
3087
3088 INIT_DELAYED_WORK(&chan->retrans_timer, l2cap_retrans_timeout);
3089 INIT_DELAYED_WORK(&chan->monitor_timer, l2cap_monitor_timeout);
3090 INIT_DELAYED_WORK(&chan->ack_timer, l2cap_ack_timeout);
3091
3092 skb_queue_head_init(&chan->srej_q);
3093
3094 err = l2cap_seq_list_init(&chan->srej_list, chan->tx_win);
3095 if (err < 0)
3096 return err;
3097
3098 err = l2cap_seq_list_init(&chan->retrans_list, chan->remote_tx_win);
3099 if (err < 0)
3100 l2cap_seq_list_free(&chan->srej_list);
3101
3102 return err;
3103 }
3104
3105 static inline __u8 l2cap_select_mode(__u8 mode, __u16 remote_feat_mask)
3106 {
3107 switch (mode) {
3108 case L2CAP_MODE_STREAMING:
3109 case L2CAP_MODE_ERTM:
3110 if (l2cap_mode_supported(mode, remote_feat_mask))
3111 return mode;
3112 /* fall through */
3113 default:
3114 return L2CAP_MODE_BASIC;
3115 }
3116 }
3117
3118 static inline bool __l2cap_ews_supported(struct l2cap_conn *conn)
3119 {
3120 return ((conn->local_fixed_chan & L2CAP_FC_A2MP) &&
3121 (conn->feat_mask & L2CAP_FEAT_EXT_WINDOW));
3122 }
3123
3124 static inline bool __l2cap_efs_supported(struct l2cap_conn *conn)
3125 {
3126 return ((conn->local_fixed_chan & L2CAP_FC_A2MP) &&
3127 (conn->feat_mask & L2CAP_FEAT_EXT_FLOW));
3128 }
3129
3130 static void __l2cap_set_ertm_timeouts(struct l2cap_chan *chan,
3131 struct l2cap_conf_rfc *rfc)
3132 {
3133 if (chan->local_amp_id != AMP_ID_BREDR && chan->hs_hcon) {
3134 u64 ertm_to = chan->hs_hcon->hdev->amp_be_flush_to;
3135
3136 /* Class 1 devices have must have ERTM timeouts
3137 * exceeding the Link Supervision Timeout. The
3138 * default Link Supervision Timeout for AMP
3139 * controllers is 10 seconds.
3140 *
3141 * Class 1 devices use 0xffffffff for their
3142 * best-effort flush timeout, so the clamping logic
3143 * will result in a timeout that meets the above
3144 * requirement. ERTM timeouts are 16-bit values, so
3145 * the maximum timeout is 65.535 seconds.
3146 */
3147
3148 /* Convert timeout to milliseconds and round */
3149 ertm_to = DIV_ROUND_UP_ULL(ertm_to, 1000);
3150
3151 /* This is the recommended formula for class 2 devices
3152 * that start ERTM timers when packets are sent to the
3153 * controller.
3154 */
3155 ertm_to = 3 * ertm_to + 500;
3156
3157 if (ertm_to > 0xffff)
3158 ertm_to = 0xffff;
3159
3160 rfc->retrans_timeout = cpu_to_le16((u16) ertm_to);
3161 rfc->monitor_timeout = rfc->retrans_timeout;
3162 } else {
3163 rfc->retrans_timeout = cpu_to_le16(L2CAP_DEFAULT_RETRANS_TO);
3164 rfc->monitor_timeout = cpu_to_le16(L2CAP_DEFAULT_MONITOR_TO);
3165 }
3166 }
3167
3168 static inline void l2cap_txwin_setup(struct l2cap_chan *chan)
3169 {
3170 if (chan->tx_win > L2CAP_DEFAULT_TX_WINDOW &&
3171 __l2cap_ews_supported(chan->conn)) {
3172 /* use extended control field */
3173 set_bit(FLAG_EXT_CTRL, &chan->flags);
3174 chan->tx_win_max = L2CAP_DEFAULT_EXT_WINDOW;
3175 } else {
3176 chan->tx_win = min_t(u16, chan->tx_win,
3177 L2CAP_DEFAULT_TX_WINDOW);
3178 chan->tx_win_max = L2CAP_DEFAULT_TX_WINDOW;
3179 }
3180 chan->ack_win = chan->tx_win;
3181 }
3182
3183 static int l2cap_build_conf_req(struct l2cap_chan *chan, void *data)
3184 {
3185 struct l2cap_conf_req *req = data;
3186 struct l2cap_conf_rfc rfc = { .mode = chan->mode };
3187 void *ptr = req->data;
3188 u16 size;
3189
3190 BT_DBG("chan %p", chan);
3191
3192 if (chan->num_conf_req || chan->num_conf_rsp)
3193 goto done;
3194
3195 switch (chan->mode) {
3196 case L2CAP_MODE_STREAMING:
3197 case L2CAP_MODE_ERTM:
3198 if (test_bit(CONF_STATE2_DEVICE, &chan->conf_state))
3199 break;
3200
3201 if (__l2cap_efs_supported(chan->conn))
3202 set_bit(FLAG_EFS_ENABLE, &chan->flags);
3203
3204 /* fall through */
3205 default:
3206 chan->mode = l2cap_select_mode(rfc.mode, chan->conn->feat_mask);
3207 break;
3208 }
3209
3210 done:
3211 if (chan->imtu != L2CAP_DEFAULT_MTU)
3212 l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->imtu);
3213
3214 switch (chan->mode) {
3215 case L2CAP_MODE_BASIC:
3216 if (disable_ertm)
3217 break;
3218
3219 if (!(chan->conn->feat_mask & L2CAP_FEAT_ERTM) &&
3220 !(chan->conn->feat_mask & L2CAP_FEAT_STREAMING))
3221 break;
3222
3223 rfc.mode = L2CAP_MODE_BASIC;
3224 rfc.txwin_size = 0;
3225 rfc.max_transmit = 0;
3226 rfc.retrans_timeout = 0;
3227 rfc.monitor_timeout = 0;
3228 rfc.max_pdu_size = 0;
3229
3230 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3231 (unsigned long) &rfc);
3232 break;
3233
3234 case L2CAP_MODE_ERTM:
3235 rfc.mode = L2CAP_MODE_ERTM;
3236 rfc.max_transmit = chan->max_tx;
3237
3238 __l2cap_set_ertm_timeouts(chan, &rfc);
3239
3240 size = min_t(u16, L2CAP_DEFAULT_MAX_PDU_SIZE, chan->conn->mtu -
3241 L2CAP_EXT_HDR_SIZE - L2CAP_SDULEN_SIZE -
3242 L2CAP_FCS_SIZE);
3243 rfc.max_pdu_size = cpu_to_le16(size);
3244
3245 l2cap_txwin_setup(chan);
3246
3247 rfc.txwin_size = min_t(u16, chan->tx_win,
3248 L2CAP_DEFAULT_TX_WINDOW);
3249
3250 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3251 (unsigned long) &rfc);
3252
3253 if (test_bit(FLAG_EFS_ENABLE, &chan->flags))
3254 l2cap_add_opt_efs(&ptr, chan);
3255
3256 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
3257 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EWS, 2,
3258 chan->tx_win);
3259
3260 if (chan->conn->feat_mask & L2CAP_FEAT_FCS)
3261 if (chan->fcs == L2CAP_FCS_NONE ||
3262 test_bit(CONF_RECV_NO_FCS, &chan->conf_state)) {
3263 chan->fcs = L2CAP_FCS_NONE;
3264 l2cap_add_conf_opt(&ptr, L2CAP_CONF_FCS, 1,
3265 chan->fcs);
3266 }
3267 break;
3268
3269 case L2CAP_MODE_STREAMING:
3270 l2cap_txwin_setup(chan);
3271 rfc.mode = L2CAP_MODE_STREAMING;
3272 rfc.txwin_size = 0;
3273 rfc.max_transmit = 0;
3274 rfc.retrans_timeout = 0;
3275 rfc.monitor_timeout = 0;
3276
3277 size = min_t(u16, L2CAP_DEFAULT_MAX_PDU_SIZE, chan->conn->mtu -
3278 L2CAP_EXT_HDR_SIZE - L2CAP_SDULEN_SIZE -
3279 L2CAP_FCS_SIZE);
3280 rfc.max_pdu_size = cpu_to_le16(size);
3281
3282 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3283 (unsigned long) &rfc);
3284
3285 if (test_bit(FLAG_EFS_ENABLE, &chan->flags))
3286 l2cap_add_opt_efs(&ptr, chan);
3287
3288 if (chan->conn->feat_mask & L2CAP_FEAT_FCS)
3289 if (chan->fcs == L2CAP_FCS_NONE ||
3290 test_bit(CONF_RECV_NO_FCS, &chan->conf_state)) {
3291 chan->fcs = L2CAP_FCS_NONE;
3292 l2cap_add_conf_opt(&ptr, L2CAP_CONF_FCS, 1,
3293 chan->fcs);
3294 }
3295 break;
3296 }
3297
3298 req->dcid = cpu_to_le16(chan->dcid);
3299 req->flags = cpu_to_le16(0);
3300
3301 return ptr - data;
3302 }
3303
3304 static int l2cap_parse_conf_req(struct l2cap_chan *chan, void *data)
3305 {
3306 struct l2cap_conf_rsp *rsp = data;
3307 void *ptr = rsp->data;
3308 void *req = chan->conf_req;
3309 int len = chan->conf_len;
3310 int type, hint, olen;
3311 unsigned long val;
3312 struct l2cap_conf_rfc rfc = { .mode = L2CAP_MODE_BASIC };
3313 struct l2cap_conf_efs efs;
3314 u8 remote_efs = 0;
3315 u16 mtu = L2CAP_DEFAULT_MTU;
3316 u16 result = L2CAP_CONF_SUCCESS;
3317 u16 size;
3318
3319 BT_DBG("chan %p", chan);
3320
3321 while (len >= L2CAP_CONF_OPT_SIZE) {
3322 len -= l2cap_get_conf_opt(&req, &type, &olen, &val);
3323
3324 hint = type & L2CAP_CONF_HINT;
3325 type &= L2CAP_CONF_MASK;
3326
3327 switch (type) {
3328 case L2CAP_CONF_MTU:
3329 mtu = val;
3330 break;
3331
3332 case L2CAP_CONF_FLUSH_TO:
3333 chan->flush_to = val;
3334 break;
3335
3336 case L2CAP_CONF_QOS:
3337 break;
3338
3339 case L2CAP_CONF_RFC:
3340 if (olen == sizeof(rfc))
3341 memcpy(&rfc, (void *) val, olen);
3342 break;
3343
3344 case L2CAP_CONF_FCS:
3345 if (val == L2CAP_FCS_NONE)
3346 set_bit(CONF_RECV_NO_FCS, &chan->conf_state);
3347 break;
3348
3349 case L2CAP_CONF_EFS:
3350 remote_efs = 1;
3351 if (olen == sizeof(efs))
3352 memcpy(&efs, (void *) val, olen);
3353 break;
3354
3355 case L2CAP_CONF_EWS:
3356 if (!(chan->conn->local_fixed_chan & L2CAP_FC_A2MP))
3357 return -ECONNREFUSED;
3358
3359 set_bit(FLAG_EXT_CTRL, &chan->flags);
3360 set_bit(CONF_EWS_RECV, &chan->conf_state);
3361 chan->tx_win_max = L2CAP_DEFAULT_EXT_WINDOW;
3362 chan->remote_tx_win = val;
3363 break;
3364
3365 default:
3366 if (hint)
3367 break;
3368
3369 result = L2CAP_CONF_UNKNOWN;
3370 *((u8 *) ptr++) = type;
3371 break;
3372 }
3373 }
3374
3375 if (chan->num_conf_rsp || chan->num_conf_req > 1)
3376 goto done;
3377
3378 switch (chan->mode) {
3379 case L2CAP_MODE_STREAMING:
3380 case L2CAP_MODE_ERTM:
3381 if (!test_bit(CONF_STATE2_DEVICE, &chan->conf_state)) {
3382 chan->mode = l2cap_select_mode(rfc.mode,
3383 chan->conn->feat_mask);
3384 break;
3385 }
3386
3387 if (remote_efs) {
3388 if (__l2cap_efs_supported(chan->conn))
3389 set_bit(FLAG_EFS_ENABLE, &chan->flags);
3390 else
3391 return -ECONNREFUSED;
3392 }
3393
3394 if (chan->mode != rfc.mode)
3395 return -ECONNREFUSED;
3396
3397 break;
3398 }
3399
3400 done:
3401 if (chan->mode != rfc.mode) {
3402 result = L2CAP_CONF_UNACCEPT;
3403 rfc.mode = chan->mode;
3404
3405 if (chan->num_conf_rsp == 1)
3406 return -ECONNREFUSED;
3407
3408 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3409 (unsigned long) &rfc);
3410 }
3411
3412 if (result == L2CAP_CONF_SUCCESS) {
3413 /* Configure output options and let the other side know
3414 * which ones we don't like. */
3415
3416 if (mtu < L2CAP_DEFAULT_MIN_MTU)
3417 result = L2CAP_CONF_UNACCEPT;
3418 else {
3419 chan->omtu = mtu;
3420 set_bit(CONF_MTU_DONE, &chan->conf_state);
3421 }
3422 l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->omtu);
3423
3424 if (remote_efs) {
3425 if (chan->local_stype != L2CAP_SERV_NOTRAFIC &&
3426 efs.stype != L2CAP_SERV_NOTRAFIC &&
3427 efs.stype != chan->local_stype) {
3428
3429 result = L2CAP_CONF_UNACCEPT;
3430
3431 if (chan->num_conf_req >= 1)
3432 return -ECONNREFUSED;
3433
3434 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS,
3435 sizeof(efs),
3436 (unsigned long) &efs);
3437 } else {
3438 /* Send PENDING Conf Rsp */
3439 result = L2CAP_CONF_PENDING;
3440 set_bit(CONF_LOC_CONF_PEND, &chan->conf_state);
3441 }
3442 }
3443
3444 switch (rfc.mode) {
3445 case L2CAP_MODE_BASIC:
3446 chan->fcs = L2CAP_FCS_NONE;
3447 set_bit(CONF_MODE_DONE, &chan->conf_state);
3448 break;
3449
3450 case L2CAP_MODE_ERTM:
3451 if (!test_bit(CONF_EWS_RECV, &chan->conf_state))
3452 chan->remote_tx_win = rfc.txwin_size;
3453 else
3454 rfc.txwin_size = L2CAP_DEFAULT_TX_WINDOW;
3455
3456 chan->remote_max_tx = rfc.max_transmit;
3457
3458 size = min_t(u16, le16_to_cpu(rfc.max_pdu_size),
3459 chan->conn->mtu - L2CAP_EXT_HDR_SIZE -
3460 L2CAP_SDULEN_SIZE - L2CAP_FCS_SIZE);
3461 rfc.max_pdu_size = cpu_to_le16(size);
3462 chan->remote_mps = size;
3463
3464 __l2cap_set_ertm_timeouts(chan, &rfc);
3465
3466 set_bit(CONF_MODE_DONE, &chan->conf_state);
3467
3468 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC,
3469 sizeof(rfc), (unsigned long) &rfc);
3470
3471 if (test_bit(FLAG_EFS_ENABLE, &chan->flags)) {
3472 chan->remote_id = efs.id;
3473 chan->remote_stype = efs.stype;
3474 chan->remote_msdu = le16_to_cpu(efs.msdu);
3475 chan->remote_flush_to =
3476 le32_to_cpu(efs.flush_to);
3477 chan->remote_acc_lat =
3478 le32_to_cpu(efs.acc_lat);
3479 chan->remote_sdu_itime =
3480 le32_to_cpu(efs.sdu_itime);
3481 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS,
3482 sizeof(efs),
3483 (unsigned long) &efs);
3484 }
3485 break;
3486
3487 case L2CAP_MODE_STREAMING:
3488 size = min_t(u16, le16_to_cpu(rfc.max_pdu_size),
3489 chan->conn->mtu - L2CAP_EXT_HDR_SIZE -
3490 L2CAP_SDULEN_SIZE - L2CAP_FCS_SIZE);
3491 rfc.max_pdu_size = cpu_to_le16(size);
3492 chan->remote_mps = size;
3493
3494 set_bit(CONF_MODE_DONE, &chan->conf_state);
3495
3496 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3497 (unsigned long) &rfc);
3498
3499 break;
3500
3501 default:
3502 result = L2CAP_CONF_UNACCEPT;
3503
3504 memset(&rfc, 0, sizeof(rfc));
3505 rfc.mode = chan->mode;
3506 }
3507
3508 if (result == L2CAP_CONF_SUCCESS)
3509 set_bit(CONF_OUTPUT_DONE, &chan->conf_state);
3510 }
3511 rsp->scid = cpu_to_le16(chan->dcid);
3512 rsp->result = cpu_to_le16(result);
3513 rsp->flags = cpu_to_le16(0);
3514
3515 return ptr - data;
3516 }
3517
3518 static int l2cap_parse_conf_rsp(struct l2cap_chan *chan, void *rsp, int len,
3519 void *data, u16 *result)
3520 {
3521 struct l2cap_conf_req *req = data;
3522 void *ptr = req->data;
3523 int type, olen;
3524 unsigned long val;
3525 struct l2cap_conf_rfc rfc = { .mode = L2CAP_MODE_BASIC };
3526 struct l2cap_conf_efs efs;
3527
3528 BT_DBG("chan %p, rsp %p, len %d, req %p", chan, rsp, len, data);
3529
3530 while (len >= L2CAP_CONF_OPT_SIZE) {
3531 len -= l2cap_get_conf_opt(&rsp, &type, &olen, &val);
3532
3533 switch (type) {
3534 case L2CAP_CONF_MTU:
3535 if (val < L2CAP_DEFAULT_MIN_MTU) {
3536 *result = L2CAP_CONF_UNACCEPT;
3537 chan->imtu = L2CAP_DEFAULT_MIN_MTU;
3538 } else
3539 chan->imtu = val;
3540 l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->imtu);
3541 break;
3542
3543 case L2CAP_CONF_FLUSH_TO:
3544 chan->flush_to = val;
3545 l2cap_add_conf_opt(&ptr, L2CAP_CONF_FLUSH_TO,
3546 2, chan->flush_to);
3547 break;
3548
3549 case L2CAP_CONF_RFC:
3550 if (olen == sizeof(rfc))
3551 memcpy(&rfc, (void *)val, olen);
3552
3553 if (test_bit(CONF_STATE2_DEVICE, &chan->conf_state) &&
3554 rfc.mode != chan->mode)
3555 return -ECONNREFUSED;
3556
3557 chan->fcs = 0;
3558
3559 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC,
3560 sizeof(rfc), (unsigned long) &rfc);
3561 break;
3562
3563 case L2CAP_CONF_EWS:
3564 chan->ack_win = min_t(u16, val, chan->ack_win);
3565 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EWS, 2,
3566 chan->tx_win);
3567 break;
3568
3569 case L2CAP_CONF_EFS:
3570 if (olen == sizeof(efs))
3571 memcpy(&efs, (void *)val, olen);
3572
3573 if (chan->local_stype != L2CAP_SERV_NOTRAFIC &&
3574 efs.stype != L2CAP_SERV_NOTRAFIC &&
3575 efs.stype != chan->local_stype)
3576 return -ECONNREFUSED;
3577
3578 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS, sizeof(efs),
3579 (unsigned long) &efs);
3580 break;
3581
3582 case L2CAP_CONF_FCS:
3583 if (*result == L2CAP_CONF_PENDING)
3584 if (val == L2CAP_FCS_NONE)
3585 set_bit(CONF_RECV_NO_FCS,
3586 &chan->conf_state);
3587 break;
3588 }
3589 }
3590
3591 if (chan->mode == L2CAP_MODE_BASIC && chan->mode != rfc.mode)
3592 return -ECONNREFUSED;
3593
3594 chan->mode = rfc.mode;
3595
3596 if (*result == L2CAP_CONF_SUCCESS || *result == L2CAP_CONF_PENDING) {
3597 switch (rfc.mode) {
3598 case L2CAP_MODE_ERTM:
3599 chan->retrans_timeout = le16_to_cpu(rfc.retrans_timeout);
3600 chan->monitor_timeout = le16_to_cpu(rfc.monitor_timeout);
3601 chan->mps = le16_to_cpu(rfc.max_pdu_size);
3602 if (!test_bit(FLAG_EXT_CTRL, &chan->flags))
3603 chan->ack_win = min_t(u16, chan->ack_win,
3604 rfc.txwin_size);
3605
3606 if (test_bit(FLAG_EFS_ENABLE, &chan->flags)) {
3607 chan->local_msdu = le16_to_cpu(efs.msdu);
3608 chan->local_sdu_itime =
3609 le32_to_cpu(efs.sdu_itime);
3610 chan->local_acc_lat = le32_to_cpu(efs.acc_lat);
3611 chan->local_flush_to =
3612 le32_to_cpu(efs.flush_to);
3613 }
3614 break;
3615
3616 case L2CAP_MODE_STREAMING:
3617 chan->mps = le16_to_cpu(rfc.max_pdu_size);
3618 }
3619 }
3620
3621 req->dcid = cpu_to_le16(chan->dcid);
3622 req->flags = cpu_to_le16(0);
3623
3624 return ptr - data;
3625 }
3626
3627 static int l2cap_build_conf_rsp(struct l2cap_chan *chan, void *data,
3628 u16 result, u16 flags)
3629 {
3630 struct l2cap_conf_rsp *rsp = data;
3631 void *ptr = rsp->data;
3632
3633 BT_DBG("chan %p", chan);
3634
3635 rsp->scid = cpu_to_le16(chan->dcid);
3636 rsp->result = cpu_to_le16(result);
3637 rsp->flags = cpu_to_le16(flags);
3638
3639 return ptr - data;
3640 }
3641
3642 void __l2cap_le_connect_rsp_defer(struct l2cap_chan *chan)
3643 {
3644 struct l2cap_le_conn_rsp rsp;
3645 struct l2cap_conn *conn = chan->conn;
3646
3647 BT_DBG("chan %p", chan);
3648
3649 rsp.dcid = cpu_to_le16(chan->scid);
3650 rsp.mtu = cpu_to_le16(chan->imtu);
3651 rsp.mps = cpu_to_le16(chan->mps);
3652 rsp.credits = cpu_to_le16(chan->rx_credits);
3653 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
3654
3655 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CONN_RSP, sizeof(rsp),
3656 &rsp);
3657 }
3658
3659 void __l2cap_connect_rsp_defer(struct l2cap_chan *chan)
3660 {
3661 struct l2cap_conn_rsp rsp;
3662 struct l2cap_conn *conn = chan->conn;
3663 u8 buf[128];
3664 u8 rsp_code;
3665
3666 rsp.scid = cpu_to_le16(chan->dcid);
3667 rsp.dcid = cpu_to_le16(chan->scid);
3668 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
3669 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
3670
3671 if (chan->hs_hcon)
3672 rsp_code = L2CAP_CREATE_CHAN_RSP;
3673 else
3674 rsp_code = L2CAP_CONN_RSP;
3675
3676 BT_DBG("chan %p rsp_code %u", chan, rsp_code);
3677
3678 l2cap_send_cmd(conn, chan->ident, rsp_code, sizeof(rsp), &rsp);
3679
3680 if (test_and_set_bit(CONF_REQ_SENT, &chan->conf_state))
3681 return;
3682
3683 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
3684 l2cap_build_conf_req(chan, buf), buf);
3685 chan->num_conf_req++;
3686 }
3687
3688 static void l2cap_conf_rfc_get(struct l2cap_chan *chan, void *rsp, int len)
3689 {
3690 int type, olen;
3691 unsigned long val;
3692 /* Use sane default values in case a misbehaving remote device
3693 * did not send an RFC or extended window size option.
3694 */
3695 u16 txwin_ext = chan->ack_win;
3696 struct l2cap_conf_rfc rfc = {
3697 .mode = chan->mode,
3698 .retrans_timeout = cpu_to_le16(L2CAP_DEFAULT_RETRANS_TO),
3699 .monitor_timeout = cpu_to_le16(L2CAP_DEFAULT_MONITOR_TO),
3700 .max_pdu_size = cpu_to_le16(chan->imtu),
3701 .txwin_size = min_t(u16, chan->ack_win, L2CAP_DEFAULT_TX_WINDOW),
3702 };
3703
3704 BT_DBG("chan %p, rsp %p, len %d", chan, rsp, len);
3705
3706 if ((chan->mode != L2CAP_MODE_ERTM) && (chan->mode != L2CAP_MODE_STREAMING))
3707 return;
3708
3709 while (len >= L2CAP_CONF_OPT_SIZE) {
3710 len -= l2cap_get_conf_opt(&rsp, &type, &olen, &val);
3711
3712 switch (type) {
3713 case L2CAP_CONF_RFC:
3714 if (olen == sizeof(rfc))
3715 memcpy(&rfc, (void *)val, olen);
3716 break;
3717 case L2CAP_CONF_EWS:
3718 txwin_ext = val;
3719 break;
3720 }
3721 }
3722
3723 switch (rfc.mode) {
3724 case L2CAP_MODE_ERTM:
3725 chan->retrans_timeout = le16_to_cpu(rfc.retrans_timeout);
3726 chan->monitor_timeout = le16_to_cpu(rfc.monitor_timeout);
3727 chan->mps = le16_to_cpu(rfc.max_pdu_size);
3728 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
3729 chan->ack_win = min_t(u16, chan->ack_win, txwin_ext);
3730 else
3731 chan->ack_win = min_t(u16, chan->ack_win,
3732 rfc.txwin_size);
3733 break;
3734 case L2CAP_MODE_STREAMING:
3735 chan->mps = le16_to_cpu(rfc.max_pdu_size);
3736 }
3737 }
3738
3739 static inline int l2cap_command_rej(struct l2cap_conn *conn,
3740 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
3741 u8 *data)
3742 {
3743 struct l2cap_cmd_rej_unk *rej = (struct l2cap_cmd_rej_unk *) data;
3744
3745 if (cmd_len < sizeof(*rej))
3746 return -EPROTO;
3747
3748 if (rej->reason != L2CAP_REJ_NOT_UNDERSTOOD)
3749 return 0;
3750
3751 if ((conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT) &&
3752 cmd->ident == conn->info_ident) {
3753 cancel_delayed_work(&conn->info_timer);
3754
3755 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
3756 conn->info_ident = 0;
3757
3758 l2cap_conn_start(conn);
3759 }
3760
3761 return 0;
3762 }
3763
3764 static struct l2cap_chan *l2cap_connect(struct l2cap_conn *conn,
3765 struct l2cap_cmd_hdr *cmd,
3766 u8 *data, u8 rsp_code, u8 amp_id)
3767 {
3768 struct l2cap_conn_req *req = (struct l2cap_conn_req *) data;
3769 struct l2cap_conn_rsp rsp;
3770 struct l2cap_chan *chan = NULL, *pchan;
3771 int result, status = L2CAP_CS_NO_INFO;
3772
3773 u16 dcid = 0, scid = __le16_to_cpu(req->scid);
3774 __le16 psm = req->psm;
3775
3776 BT_DBG("psm 0x%2.2x scid 0x%4.4x", __le16_to_cpu(psm), scid);
3777
3778 /* Check if we have socket listening on psm */
3779 pchan = l2cap_global_chan_by_psm(BT_LISTEN, psm, &conn->hcon->src,
3780 &conn->hcon->dst, ACL_LINK);
3781 if (!pchan) {
3782 result = L2CAP_CR_BAD_PSM;
3783 goto sendresp;
3784 }
3785
3786 mutex_lock(&conn->chan_lock);
3787 l2cap_chan_lock(pchan);
3788
3789 /* Check if the ACL is secure enough (if not SDP) */
3790 if (psm != cpu_to_le16(L2CAP_PSM_SDP) &&
3791 !hci_conn_check_link_mode(conn->hcon)) {
3792 conn->disc_reason = HCI_ERROR_AUTH_FAILURE;
3793 result = L2CAP_CR_SEC_BLOCK;
3794 goto response;
3795 }
3796
3797 result = L2CAP_CR_NO_MEM;
3798
3799 /* Check if we already have channel with that dcid */
3800 if (__l2cap_get_chan_by_dcid(conn, scid))
3801 goto response;
3802
3803 chan = pchan->ops->new_connection(pchan);
3804 if (!chan)
3805 goto response;
3806
3807 /* For certain devices (ex: HID mouse), support for authentication,
3808 * pairing and bonding is optional. For such devices, inorder to avoid
3809 * the ACL alive for too long after L2CAP disconnection, reset the ACL
3810 * disc_timeout back to HCI_DISCONN_TIMEOUT during L2CAP connect.
3811 */
3812 conn->hcon->disc_timeout = HCI_DISCONN_TIMEOUT;
3813
3814 bacpy(&chan->src, &conn->hcon->src);
3815 bacpy(&chan->dst, &conn->hcon->dst);
3816 chan->src_type = bdaddr_src_type(conn->hcon);
3817 chan->dst_type = bdaddr_dst_type(conn->hcon);
3818 chan->psm = psm;
3819 chan->dcid = scid;
3820 chan->local_amp_id = amp_id;
3821
3822 __l2cap_chan_add(conn, chan);
3823
3824 dcid = chan->scid;
3825
3826 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
3827
3828 chan->ident = cmd->ident;
3829
3830 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE) {
3831 if (l2cap_chan_check_security(chan, false)) {
3832 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
3833 l2cap_state_change(chan, BT_CONNECT2);
3834 result = L2CAP_CR_PEND;
3835 status = L2CAP_CS_AUTHOR_PEND;
3836 chan->ops->defer(chan);
3837 } else {
3838 /* Force pending result for AMP controllers.
3839 * The connection will succeed after the
3840 * physical link is up.
3841 */
3842 if (amp_id == AMP_ID_BREDR) {
3843 l2cap_state_change(chan, BT_CONFIG);
3844 result = L2CAP_CR_SUCCESS;
3845 } else {
3846 l2cap_state_change(chan, BT_CONNECT2);
3847 result = L2CAP_CR_PEND;
3848 }
3849 status = L2CAP_CS_NO_INFO;
3850 }
3851 } else {
3852 l2cap_state_change(chan, BT_CONNECT2);
3853 result = L2CAP_CR_PEND;
3854 status = L2CAP_CS_AUTHEN_PEND;
3855 }
3856 } else {
3857 l2cap_state_change(chan, BT_CONNECT2);
3858 result = L2CAP_CR_PEND;
3859 status = L2CAP_CS_NO_INFO;
3860 }
3861
3862 response:
3863 l2cap_chan_unlock(pchan);
3864 mutex_unlock(&conn->chan_lock);
3865 l2cap_chan_put(pchan);
3866
3867 sendresp:
3868 rsp.scid = cpu_to_le16(scid);
3869 rsp.dcid = cpu_to_le16(dcid);
3870 rsp.result = cpu_to_le16(result);
3871 rsp.status = cpu_to_le16(status);
3872 l2cap_send_cmd(conn, cmd->ident, rsp_code, sizeof(rsp), &rsp);
3873
3874 if (result == L2CAP_CR_PEND && status == L2CAP_CS_NO_INFO) {
3875 struct l2cap_info_req info;
3876 info.type = cpu_to_le16(L2CAP_IT_FEAT_MASK);
3877
3878 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_SENT;
3879 conn->info_ident = l2cap_get_ident(conn);
3880
3881 schedule_delayed_work(&conn->info_timer, L2CAP_INFO_TIMEOUT);
3882
3883 l2cap_send_cmd(conn, conn->info_ident, L2CAP_INFO_REQ,
3884 sizeof(info), &info);
3885 }
3886
3887 if (chan && !test_bit(CONF_REQ_SENT, &chan->conf_state) &&
3888 result == L2CAP_CR_SUCCESS) {
3889 u8 buf[128];
3890 set_bit(CONF_REQ_SENT, &chan->conf_state);
3891 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
3892 l2cap_build_conf_req(chan, buf), buf);
3893 chan->num_conf_req++;
3894 }
3895
3896 return chan;
3897 }
3898
3899 static int l2cap_connect_req(struct l2cap_conn *conn,
3900 struct l2cap_cmd_hdr *cmd, u16 cmd_len, u8 *data)
3901 {
3902 struct hci_dev *hdev = conn->hcon->hdev;
3903 struct hci_conn *hcon = conn->hcon;
3904
3905 if (cmd_len < sizeof(struct l2cap_conn_req))
3906 return -EPROTO;
3907
3908 hci_dev_lock(hdev);
3909 if (hci_dev_test_flag(hdev, HCI_MGMT) &&
3910 !test_and_set_bit(HCI_CONN_MGMT_CONNECTED, &hcon->flags))
3911 mgmt_device_connected(hdev, hcon, 0, NULL, 0);
3912 hci_dev_unlock(hdev);
3913
3914 l2cap_connect(conn, cmd, data, L2CAP_CONN_RSP, 0);
3915 return 0;
3916 }
3917
3918 static int l2cap_connect_create_rsp(struct l2cap_conn *conn,
3919 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
3920 u8 *data)
3921 {
3922 struct l2cap_conn_rsp *rsp = (struct l2cap_conn_rsp *) data;
3923 u16 scid, dcid, result, status;
3924 struct l2cap_chan *chan;
3925 u8 req[128];
3926 int err;
3927
3928 if (cmd_len < sizeof(*rsp))
3929 return -EPROTO;
3930
3931 scid = __le16_to_cpu(rsp->scid);
3932 dcid = __le16_to_cpu(rsp->dcid);
3933 result = __le16_to_cpu(rsp->result);
3934 status = __le16_to_cpu(rsp->status);
3935
3936 BT_DBG("dcid 0x%4.4x scid 0x%4.4x result 0x%2.2x status 0x%2.2x",
3937 dcid, scid, result, status);
3938
3939 mutex_lock(&conn->chan_lock);
3940
3941 if (scid) {
3942 chan = __l2cap_get_chan_by_scid(conn, scid);
3943 if (!chan) {
3944 err = -EBADSLT;
3945 goto unlock;
3946 }
3947 } else {
3948 chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
3949 if (!chan) {
3950 err = -EBADSLT;
3951 goto unlock;
3952 }
3953 }
3954
3955 err = 0;
3956
3957 l2cap_chan_lock(chan);
3958
3959 switch (result) {
3960 case L2CAP_CR_SUCCESS:
3961 l2cap_state_change(chan, BT_CONFIG);
3962 chan->ident = 0;
3963 chan->dcid = dcid;
3964 clear_bit(CONF_CONNECT_PEND, &chan->conf_state);
3965
3966 if (test_and_set_bit(CONF_REQ_SENT, &chan->conf_state))
3967 break;
3968
3969 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
3970 l2cap_build_conf_req(chan, req), req);
3971 chan->num_conf_req++;
3972 break;
3973
3974 case L2CAP_CR_PEND:
3975 set_bit(CONF_CONNECT_PEND, &chan->conf_state);
3976 break;
3977
3978 default:
3979 l2cap_chan_del(chan, ECONNREFUSED);
3980 break;
3981 }
3982
3983 l2cap_chan_unlock(chan);
3984
3985 unlock:
3986 mutex_unlock(&conn->chan_lock);
3987
3988 return err;
3989 }
3990
3991 static inline void set_default_fcs(struct l2cap_chan *chan)
3992 {
3993 /* FCS is enabled only in ERTM or streaming mode, if one or both
3994 * sides request it.
3995 */
3996 if (chan->mode != L2CAP_MODE_ERTM && chan->mode != L2CAP_MODE_STREAMING)
3997 chan->fcs = L2CAP_FCS_NONE;
3998 else if (!test_bit(CONF_RECV_NO_FCS, &chan->conf_state))
3999 chan->fcs = L2CAP_FCS_CRC16;
4000 }
4001
4002 static void l2cap_send_efs_conf_rsp(struct l2cap_chan *chan, void *data,
4003 u8 ident, u16 flags)
4004 {
4005 struct l2cap_conn *conn = chan->conn;
4006
4007 BT_DBG("conn %p chan %p ident %d flags 0x%4.4x", conn, chan, ident,
4008 flags);
4009
4010 clear_bit(CONF_LOC_CONF_PEND, &chan->conf_state);
4011 set_bit(CONF_OUTPUT_DONE, &chan->conf_state);
4012
4013 l2cap_send_cmd(conn, ident, L2CAP_CONF_RSP,
4014 l2cap_build_conf_rsp(chan, data,
4015 L2CAP_CONF_SUCCESS, flags), data);
4016 }
4017
4018 static void cmd_reject_invalid_cid(struct l2cap_conn *conn, u8 ident,
4019 u16 scid, u16 dcid)
4020 {
4021 struct l2cap_cmd_rej_cid rej;
4022
4023 rej.reason = cpu_to_le16(L2CAP_REJ_INVALID_CID);
4024 rej.scid = __cpu_to_le16(scid);
4025 rej.dcid = __cpu_to_le16(dcid);
4026
4027 l2cap_send_cmd(conn, ident, L2CAP_COMMAND_REJ, sizeof(rej), &rej);
4028 }
4029
4030 static inline int l2cap_config_req(struct l2cap_conn *conn,
4031 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4032 u8 *data)
4033 {
4034 struct l2cap_conf_req *req = (struct l2cap_conf_req *) data;
4035 u16 dcid, flags;
4036 u8 rsp[64];
4037 struct l2cap_chan *chan;
4038 int len, err = 0;
4039
4040 if (cmd_len < sizeof(*req))
4041 return -EPROTO;
4042
4043 dcid = __le16_to_cpu(req->dcid);
4044 flags = __le16_to_cpu(req->flags);
4045
4046 BT_DBG("dcid 0x%4.4x flags 0x%2.2x", dcid, flags);
4047
4048 chan = l2cap_get_chan_by_scid(conn, dcid);
4049 if (!chan) {
4050 cmd_reject_invalid_cid(conn, cmd->ident, dcid, 0);
4051 return 0;
4052 }
4053
4054 if (chan->state != BT_CONFIG && chan->state != BT_CONNECT2) {
4055 cmd_reject_invalid_cid(conn, cmd->ident, chan->scid,
4056 chan->dcid);
4057 goto unlock;
4058 }
4059
4060 /* Reject if config buffer is too small. */
4061 len = cmd_len - sizeof(*req);
4062 if (chan->conf_len + len > sizeof(chan->conf_req)) {
4063 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP,
4064 l2cap_build_conf_rsp(chan, rsp,
4065 L2CAP_CONF_REJECT, flags), rsp);
4066 goto unlock;
4067 }
4068
4069 /* Store config. */
4070 memcpy(chan->conf_req + chan->conf_len, req->data, len);
4071 chan->conf_len += len;
4072
4073 if (flags & L2CAP_CONF_FLAG_CONTINUATION) {
4074 /* Incomplete config. Send empty response. */
4075 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP,
4076 l2cap_build_conf_rsp(chan, rsp,
4077 L2CAP_CONF_SUCCESS, flags), rsp);
4078 goto unlock;
4079 }
4080
4081 /* Complete config. */
4082 len = l2cap_parse_conf_req(chan, rsp);
4083 if (len < 0) {
4084 l2cap_send_disconn_req(chan, ECONNRESET);
4085 goto unlock;
4086 }
4087
4088 chan->ident = cmd->ident;
4089 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP, len, rsp);
4090 chan->num_conf_rsp++;
4091
4092 /* Reset config buffer. */
4093 chan->conf_len = 0;
4094
4095 if (!test_bit(CONF_OUTPUT_DONE, &chan->conf_state))
4096 goto unlock;
4097
4098 if (test_bit(CONF_INPUT_DONE, &chan->conf_state)) {
4099 set_default_fcs(chan);
4100
4101 if (chan->mode == L2CAP_MODE_ERTM ||
4102 chan->mode == L2CAP_MODE_STREAMING)
4103 err = l2cap_ertm_init(chan);
4104
4105 if (err < 0)
4106 l2cap_send_disconn_req(chan, -err);
4107 else
4108 l2cap_chan_ready(chan);
4109
4110 goto unlock;
4111 }
4112
4113 if (!test_and_set_bit(CONF_REQ_SENT, &chan->conf_state)) {
4114 u8 buf[64];
4115 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
4116 l2cap_build_conf_req(chan, buf), buf);
4117 chan->num_conf_req++;
4118 }
4119
4120 /* Got Conf Rsp PENDING from remote side and assume we sent
4121 Conf Rsp PENDING in the code above */
4122 if (test_bit(CONF_REM_CONF_PEND, &chan->conf_state) &&
4123 test_bit(CONF_LOC_CONF_PEND, &chan->conf_state)) {
4124
4125 /* check compatibility */
4126
4127 /* Send rsp for BR/EDR channel */
4128 if (!chan->hs_hcon)
4129 l2cap_send_efs_conf_rsp(chan, rsp, cmd->ident, flags);
4130 else
4131 chan->ident = cmd->ident;
4132 }
4133
4134 unlock:
4135 l2cap_chan_unlock(chan);
4136 return err;
4137 }
4138
4139 static inline int l2cap_config_rsp(struct l2cap_conn *conn,
4140 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4141 u8 *data)
4142 {
4143 struct l2cap_conf_rsp *rsp = (struct l2cap_conf_rsp *)data;
4144 u16 scid, flags, result;
4145 struct l2cap_chan *chan;
4146 int len = cmd_len - sizeof(*rsp);
4147 int err = 0;
4148
4149 if (cmd_len < sizeof(*rsp))
4150 return -EPROTO;
4151
4152 scid = __le16_to_cpu(rsp->scid);
4153 flags = __le16_to_cpu(rsp->flags);
4154 result = __le16_to_cpu(rsp->result);
4155
4156 BT_DBG("scid 0x%4.4x flags 0x%2.2x result 0x%2.2x len %d", scid, flags,
4157 result, len);
4158
4159 chan = l2cap_get_chan_by_scid(conn, scid);
4160 if (!chan)
4161 return 0;
4162
4163 switch (result) {
4164 case L2CAP_CONF_SUCCESS:
4165 l2cap_conf_rfc_get(chan, rsp->data, len);
4166 clear_bit(CONF_REM_CONF_PEND, &chan->conf_state);
4167 break;
4168
4169 case L2CAP_CONF_PENDING:
4170 set_bit(CONF_REM_CONF_PEND, &chan->conf_state);
4171
4172 if (test_bit(CONF_LOC_CONF_PEND, &chan->conf_state)) {
4173 char buf[64];
4174
4175 len = l2cap_parse_conf_rsp(chan, rsp->data, len,
4176 buf, &result);
4177 if (len < 0) {
4178 l2cap_send_disconn_req(chan, ECONNRESET);
4179 goto done;
4180 }
4181
4182 if (!chan->hs_hcon) {
4183 l2cap_send_efs_conf_rsp(chan, buf, cmd->ident,
4184 0);
4185 } else {
4186 if (l2cap_check_efs(chan)) {
4187 amp_create_logical_link(chan);
4188 chan->ident = cmd->ident;
4189 }
4190 }
4191 }
4192 goto done;
4193
4194 case L2CAP_CONF_UNACCEPT:
4195 if (chan->num_conf_rsp <= L2CAP_CONF_MAX_CONF_RSP) {
4196 char req[64];
4197
4198 if (len > sizeof(req) - sizeof(struct l2cap_conf_req)) {
4199 l2cap_send_disconn_req(chan, ECONNRESET);
4200 goto done;
4201 }
4202
4203 /* throw out any old stored conf requests */
4204 result = L2CAP_CONF_SUCCESS;
4205 len = l2cap_parse_conf_rsp(chan, rsp->data, len,
4206 req, &result);
4207 if (len < 0) {
4208 l2cap_send_disconn_req(chan, ECONNRESET);
4209 goto done;
4210 }
4211
4212 l2cap_send_cmd(conn, l2cap_get_ident(conn),
4213 L2CAP_CONF_REQ, len, req);
4214 chan->num_conf_req++;
4215 if (result != L2CAP_CONF_SUCCESS)
4216 goto done;
4217 break;
4218 }
4219
4220 default:
4221 l2cap_chan_set_err(chan, ECONNRESET);
4222
4223 __set_chan_timer(chan, L2CAP_DISC_REJ_TIMEOUT);
4224 l2cap_send_disconn_req(chan, ECONNRESET);
4225 goto done;
4226 }
4227
4228 if (flags & L2CAP_CONF_FLAG_CONTINUATION)
4229 goto done;
4230
4231 set_bit(CONF_INPUT_DONE, &chan->conf_state);
4232
4233 if (test_bit(CONF_OUTPUT_DONE, &chan->conf_state)) {
4234 set_default_fcs(chan);
4235
4236 if (chan->mode == L2CAP_MODE_ERTM ||
4237 chan->mode == L2CAP_MODE_STREAMING)
4238 err = l2cap_ertm_init(chan);
4239
4240 if (err < 0)
4241 l2cap_send_disconn_req(chan, -err);
4242 else
4243 l2cap_chan_ready(chan);
4244 }
4245
4246 done:
4247 l2cap_chan_unlock(chan);
4248 return err;
4249 }
4250
4251 static inline int l2cap_disconnect_req(struct l2cap_conn *conn,
4252 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4253 u8 *data)
4254 {
4255 struct l2cap_disconn_req *req = (struct l2cap_disconn_req *) data;
4256 struct l2cap_disconn_rsp rsp;
4257 u16 dcid, scid;
4258 struct l2cap_chan *chan;
4259
4260 if (cmd_len != sizeof(*req))
4261 return -EPROTO;
4262
4263 scid = __le16_to_cpu(req->scid);
4264 dcid = __le16_to_cpu(req->dcid);
4265
4266 BT_DBG("scid 0x%4.4x dcid 0x%4.4x", scid, dcid);
4267
4268 mutex_lock(&conn->chan_lock);
4269
4270 chan = __l2cap_get_chan_by_scid(conn, dcid);
4271 if (!chan) {
4272 mutex_unlock(&conn->chan_lock);
4273 cmd_reject_invalid_cid(conn, cmd->ident, dcid, scid);
4274 return 0;
4275 }
4276
4277 l2cap_chan_lock(chan);
4278
4279 rsp.dcid = cpu_to_le16(chan->scid);
4280 rsp.scid = cpu_to_le16(chan->dcid);
4281 l2cap_send_cmd(conn, cmd->ident, L2CAP_DISCONN_RSP, sizeof(rsp), &rsp);
4282
4283 chan->ops->set_shutdown(chan);
4284
4285 l2cap_chan_hold(chan);
4286 l2cap_chan_del(chan, ECONNRESET);
4287
4288 l2cap_chan_unlock(chan);
4289
4290 chan->ops->close(chan);
4291 l2cap_chan_put(chan);
4292
4293 mutex_unlock(&conn->chan_lock);
4294
4295 return 0;
4296 }
4297
4298 static inline int l2cap_disconnect_rsp(struct l2cap_conn *conn,
4299 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4300 u8 *data)
4301 {
4302 struct l2cap_disconn_rsp *rsp = (struct l2cap_disconn_rsp *) data;
4303 u16 dcid, scid;
4304 struct l2cap_chan *chan;
4305
4306 if (cmd_len != sizeof(*rsp))
4307 return -EPROTO;
4308
4309 scid = __le16_to_cpu(rsp->scid);
4310 dcid = __le16_to_cpu(rsp->dcid);
4311
4312 BT_DBG("dcid 0x%4.4x scid 0x%4.4x", dcid, scid);
4313
4314 mutex_lock(&conn->chan_lock);
4315
4316 chan = __l2cap_get_chan_by_scid(conn, scid);
4317 if (!chan) {
4318 mutex_unlock(&conn->chan_lock);
4319 return 0;
4320 }
4321
4322 l2cap_chan_lock(chan);
4323
4324 l2cap_chan_hold(chan);
4325 l2cap_chan_del(chan, 0);
4326
4327 l2cap_chan_unlock(chan);
4328
4329 chan->ops->close(chan);
4330 l2cap_chan_put(chan);
4331
4332 mutex_unlock(&conn->chan_lock);
4333
4334 return 0;
4335 }
4336
4337 static inline int l2cap_information_req(struct l2cap_conn *conn,
4338 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4339 u8 *data)
4340 {
4341 struct l2cap_info_req *req = (struct l2cap_info_req *) data;
4342 u16 type;
4343
4344 if (cmd_len != sizeof(*req))
4345 return -EPROTO;
4346
4347 type = __le16_to_cpu(req->type);
4348
4349 BT_DBG("type 0x%4.4x", type);
4350
4351 if (type == L2CAP_IT_FEAT_MASK) {
4352 u8 buf[8];
4353 u32 feat_mask = l2cap_feat_mask;
4354 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) buf;
4355 rsp->type = cpu_to_le16(L2CAP_IT_FEAT_MASK);
4356 rsp->result = cpu_to_le16(L2CAP_IR_SUCCESS);
4357 if (!disable_ertm)
4358 feat_mask |= L2CAP_FEAT_ERTM | L2CAP_FEAT_STREAMING
4359 | L2CAP_FEAT_FCS;
4360 if (conn->local_fixed_chan & L2CAP_FC_A2MP)
4361 feat_mask |= L2CAP_FEAT_EXT_FLOW
4362 | L2CAP_FEAT_EXT_WINDOW;
4363
4364 put_unaligned_le32(feat_mask, rsp->data);
4365 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(buf),
4366 buf);
4367 } else if (type == L2CAP_IT_FIXED_CHAN) {
4368 u8 buf[12];
4369 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) buf;
4370
4371 rsp->type = cpu_to_le16(L2CAP_IT_FIXED_CHAN);
4372 rsp->result = cpu_to_le16(L2CAP_IR_SUCCESS);
4373 rsp->data[0] = conn->local_fixed_chan;
4374 memset(rsp->data + 1, 0, 7);
4375 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(buf),
4376 buf);
4377 } else {
4378 struct l2cap_info_rsp rsp;
4379 rsp.type = cpu_to_le16(type);
4380 rsp.result = cpu_to_le16(L2CAP_IR_NOTSUPP);
4381 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(rsp),
4382 &rsp);
4383 }
4384
4385 return 0;
4386 }
4387
4388 static inline int l2cap_information_rsp(struct l2cap_conn *conn,
4389 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4390 u8 *data)
4391 {
4392 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) data;
4393 u16 type, result;
4394
4395 if (cmd_len < sizeof(*rsp))
4396 return -EPROTO;
4397
4398 type = __le16_to_cpu(rsp->type);
4399 result = __le16_to_cpu(rsp->result);
4400
4401 BT_DBG("type 0x%4.4x result 0x%2.2x", type, result);
4402
4403 /* L2CAP Info req/rsp are unbound to channels, add extra checks */
4404 if (cmd->ident != conn->info_ident ||
4405 conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE)
4406 return 0;
4407
4408 cancel_delayed_work(&conn->info_timer);
4409
4410 if (result != L2CAP_IR_SUCCESS) {
4411 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4412 conn->info_ident = 0;
4413
4414 l2cap_conn_start(conn);
4415
4416 return 0;
4417 }
4418
4419 switch (type) {
4420 case L2CAP_IT_FEAT_MASK:
4421 conn->feat_mask = get_unaligned_le32(rsp->data);
4422
4423 if (conn->feat_mask & L2CAP_FEAT_FIXED_CHAN) {
4424 struct l2cap_info_req req;
4425 req.type = cpu_to_le16(L2CAP_IT_FIXED_CHAN);
4426
4427 conn->info_ident = l2cap_get_ident(conn);
4428
4429 l2cap_send_cmd(conn, conn->info_ident,
4430 L2CAP_INFO_REQ, sizeof(req), &req);
4431 } else {
4432 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4433 conn->info_ident = 0;
4434
4435 l2cap_conn_start(conn);
4436 }
4437 break;
4438
4439 case L2CAP_IT_FIXED_CHAN:
4440 conn->remote_fixed_chan = rsp->data[0];
4441 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4442 conn->info_ident = 0;
4443
4444 l2cap_conn_start(conn);
4445 break;
4446 }
4447
4448 return 0;
4449 }
4450
4451 static int l2cap_create_channel_req(struct l2cap_conn *conn,
4452 struct l2cap_cmd_hdr *cmd,
4453 u16 cmd_len, void *data)
4454 {
4455 struct l2cap_create_chan_req *req = data;
4456 struct l2cap_create_chan_rsp rsp;
4457 struct l2cap_chan *chan;
4458 struct hci_dev *hdev;
4459 u16 psm, scid;
4460
4461 if (cmd_len != sizeof(*req))
4462 return -EPROTO;
4463
4464 if (!(conn->local_fixed_chan & L2CAP_FC_A2MP))
4465 return -EINVAL;
4466
4467 psm = le16_to_cpu(req->psm);
4468 scid = le16_to_cpu(req->scid);
4469
4470 BT_DBG("psm 0x%2.2x, scid 0x%4.4x, amp_id %d", psm, scid, req->amp_id);
4471
4472 /* For controller id 0 make BR/EDR connection */
4473 if (req->amp_id == AMP_ID_BREDR) {
4474 l2cap_connect(conn, cmd, data, L2CAP_CREATE_CHAN_RSP,
4475 req->amp_id);
4476 return 0;
4477 }
4478
4479 /* Validate AMP controller id */
4480 hdev = hci_dev_get(req->amp_id);
4481 if (!hdev)
4482 goto error;
4483
4484 if (hdev->dev_type != HCI_AMP || !test_bit(HCI_UP, &hdev->flags)) {
4485 hci_dev_put(hdev);
4486 goto error;
4487 }
4488
4489 chan = l2cap_connect(conn, cmd, data, L2CAP_CREATE_CHAN_RSP,
4490 req->amp_id);
4491 if (chan) {
4492 struct amp_mgr *mgr = conn->hcon->amp_mgr;
4493 struct hci_conn *hs_hcon;
4494
4495 hs_hcon = hci_conn_hash_lookup_ba(hdev, AMP_LINK,
4496 &conn->hcon->dst);
4497 if (!hs_hcon) {
4498 hci_dev_put(hdev);
4499 cmd_reject_invalid_cid(conn, cmd->ident, chan->scid,
4500 chan->dcid);
4501 return 0;
4502 }
4503
4504 BT_DBG("mgr %p bredr_chan %p hs_hcon %p", mgr, chan, hs_hcon);
4505
4506 mgr->bredr_chan = chan;
4507 chan->hs_hcon = hs_hcon;
4508 chan->fcs = L2CAP_FCS_NONE;
4509 conn->mtu = hdev->block_mtu;
4510 }
4511
4512 hci_dev_put(hdev);
4513
4514 return 0;
4515
4516 error:
4517 rsp.dcid = 0;
4518 rsp.scid = cpu_to_le16(scid);
4519 rsp.result = cpu_to_le16(L2CAP_CR_BAD_AMP);
4520 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
4521
4522 l2cap_send_cmd(conn, cmd->ident, L2CAP_CREATE_CHAN_RSP,
4523 sizeof(rsp), &rsp);
4524
4525 return 0;
4526 }
4527
4528 static void l2cap_send_move_chan_req(struct l2cap_chan *chan, u8 dest_amp_id)
4529 {
4530 struct l2cap_move_chan_req req;
4531 u8 ident;
4532
4533 BT_DBG("chan %p, dest_amp_id %d", chan, dest_amp_id);
4534
4535 ident = l2cap_get_ident(chan->conn);
4536 chan->ident = ident;
4537
4538 req.icid = cpu_to_le16(chan->scid);
4539 req.dest_amp_id = dest_amp_id;
4540
4541 l2cap_send_cmd(chan->conn, ident, L2CAP_MOVE_CHAN_REQ, sizeof(req),
4542 &req);
4543
4544 __set_chan_timer(chan, L2CAP_MOVE_TIMEOUT);
4545 }
4546
4547 static void l2cap_send_move_chan_rsp(struct l2cap_chan *chan, u16 result)
4548 {
4549 struct l2cap_move_chan_rsp rsp;
4550
4551 BT_DBG("chan %p, result 0x%4.4x", chan, result);
4552
4553 rsp.icid = cpu_to_le16(chan->dcid);
4554 rsp.result = cpu_to_le16(result);
4555
4556 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_MOVE_CHAN_RSP,
4557 sizeof(rsp), &rsp);
4558 }
4559
4560 static void l2cap_send_move_chan_cfm(struct l2cap_chan *chan, u16 result)
4561 {
4562 struct l2cap_move_chan_cfm cfm;
4563
4564 BT_DBG("chan %p, result 0x%4.4x", chan, result);
4565
4566 chan->ident = l2cap_get_ident(chan->conn);
4567
4568 cfm.icid = cpu_to_le16(chan->scid);
4569 cfm.result = cpu_to_le16(result);
4570
4571 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_MOVE_CHAN_CFM,
4572 sizeof(cfm), &cfm);
4573
4574 __set_chan_timer(chan, L2CAP_MOVE_TIMEOUT);
4575 }
4576
4577 static void l2cap_send_move_chan_cfm_icid(struct l2cap_conn *conn, u16 icid)
4578 {
4579 struct l2cap_move_chan_cfm cfm;
4580
4581 BT_DBG("conn %p, icid 0x%4.4x", conn, icid);
4582
4583 cfm.icid = cpu_to_le16(icid);
4584 cfm.result = cpu_to_le16(L2CAP_MC_UNCONFIRMED);
4585
4586 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_MOVE_CHAN_CFM,
4587 sizeof(cfm), &cfm);
4588 }
4589
4590 static void l2cap_send_move_chan_cfm_rsp(struct l2cap_conn *conn, u8 ident,
4591 u16 icid)
4592 {
4593 struct l2cap_move_chan_cfm_rsp rsp;
4594
4595 BT_DBG("icid 0x%4.4x", icid);
4596
4597 rsp.icid = cpu_to_le16(icid);
4598 l2cap_send_cmd(conn, ident, L2CAP_MOVE_CHAN_CFM_RSP, sizeof(rsp), &rsp);
4599 }
4600
4601 static void __release_logical_link(struct l2cap_chan *chan)
4602 {
4603 chan->hs_hchan = NULL;
4604 chan->hs_hcon = NULL;
4605
4606 /* Placeholder - release the logical link */
4607 }
4608
4609 static void l2cap_logical_fail(struct l2cap_chan *chan)
4610 {
4611 /* Logical link setup failed */
4612 if (chan->state != BT_CONNECTED) {
4613 /* Create channel failure, disconnect */
4614 l2cap_send_disconn_req(chan, ECONNRESET);
4615 return;
4616 }
4617
4618 switch (chan->move_role) {
4619 case L2CAP_MOVE_ROLE_RESPONDER:
4620 l2cap_move_done(chan);
4621 l2cap_send_move_chan_rsp(chan, L2CAP_MR_NOT_SUPP);
4622 break;
4623 case L2CAP_MOVE_ROLE_INITIATOR:
4624 if (chan->move_state == L2CAP_MOVE_WAIT_LOGICAL_COMP ||
4625 chan->move_state == L2CAP_MOVE_WAIT_LOGICAL_CFM) {
4626 /* Remote has only sent pending or
4627 * success responses, clean up
4628 */
4629 l2cap_move_done(chan);
4630 }
4631
4632 /* Other amp move states imply that the move
4633 * has already aborted
4634 */
4635 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
4636 break;
4637 }
4638 }
4639
4640 static void l2cap_logical_finish_create(struct l2cap_chan *chan,
4641 struct hci_chan *hchan)
4642 {
4643 struct l2cap_conf_rsp rsp;
4644
4645 chan->hs_hchan = hchan;
4646 chan->hs_hcon->l2cap_data = chan->conn;
4647
4648 l2cap_send_efs_conf_rsp(chan, &rsp, chan->ident, 0);
4649
4650 if (test_bit(CONF_INPUT_DONE, &chan->conf_state)) {
4651 int err;
4652
4653 set_default_fcs(chan);
4654
4655 err = l2cap_ertm_init(chan);
4656 if (err < 0)
4657 l2cap_send_disconn_req(chan, -err);
4658 else
4659 l2cap_chan_ready(chan);
4660 }
4661 }
4662
4663 static void l2cap_logical_finish_move(struct l2cap_chan *chan,
4664 struct hci_chan *hchan)
4665 {
4666 chan->hs_hcon = hchan->conn;
4667 chan->hs_hcon->l2cap_data = chan->conn;
4668
4669 BT_DBG("move_state %d", chan->move_state);
4670
4671 switch (chan->move_state) {
4672 case L2CAP_MOVE_WAIT_LOGICAL_COMP:
4673 /* Move confirm will be sent after a success
4674 * response is received
4675 */
4676 chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
4677 break;
4678 case L2CAP_MOVE_WAIT_LOGICAL_CFM:
4679 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
4680 chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
4681 } else if (chan->move_role == L2CAP_MOVE_ROLE_INITIATOR) {
4682 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM_RSP;
4683 l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
4684 } else if (chan->move_role == L2CAP_MOVE_ROLE_RESPONDER) {
4685 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
4686 l2cap_send_move_chan_rsp(chan, L2CAP_MR_SUCCESS);
4687 }
4688 break;
4689 default:
4690 /* Move was not in expected state, free the channel */
4691 __release_logical_link(chan);
4692
4693 chan->move_state = L2CAP_MOVE_STABLE;
4694 }
4695 }
4696
4697 /* Call with chan locked */
4698 void l2cap_logical_cfm(struct l2cap_chan *chan, struct hci_chan *hchan,
4699 u8 status)
4700 {
4701 BT_DBG("chan %p, hchan %p, status %d", chan, hchan, status);
4702
4703 if (status) {
4704 l2cap_logical_fail(chan);
4705 __release_logical_link(chan);
4706 return;
4707 }
4708
4709 if (chan->state != BT_CONNECTED) {
4710 /* Ignore logical link if channel is on BR/EDR */
4711 if (chan->local_amp_id != AMP_ID_BREDR)
4712 l2cap_logical_finish_create(chan, hchan);
4713 } else {
4714 l2cap_logical_finish_move(chan, hchan);
4715 }
4716 }
4717
4718 void l2cap_move_start(struct l2cap_chan *chan)
4719 {
4720 BT_DBG("chan %p", chan);
4721
4722 if (chan->local_amp_id == AMP_ID_BREDR) {
4723 if (chan->chan_policy != BT_CHANNEL_POLICY_AMP_PREFERRED)
4724 return;
4725 chan->move_role = L2CAP_MOVE_ROLE_INITIATOR;
4726 chan->move_state = L2CAP_MOVE_WAIT_PREPARE;
4727 /* Placeholder - start physical link setup */
4728 } else {
4729 chan->move_role = L2CAP_MOVE_ROLE_INITIATOR;
4730 chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
4731 chan->move_id = 0;
4732 l2cap_move_setup(chan);
4733 l2cap_send_move_chan_req(chan, 0);
4734 }
4735 }
4736
4737 static void l2cap_do_create(struct l2cap_chan *chan, int result,
4738 u8 local_amp_id, u8 remote_amp_id)
4739 {
4740 BT_DBG("chan %p state %s %u -> %u", chan, state_to_string(chan->state),
4741 local_amp_id, remote_amp_id);
4742
4743 chan->fcs = L2CAP_FCS_NONE;
4744
4745 /* Outgoing channel on AMP */
4746 if (chan->state == BT_CONNECT) {
4747 if (result == L2CAP_CR_SUCCESS) {
4748 chan->local_amp_id = local_amp_id;
4749 l2cap_send_create_chan_req(chan, remote_amp_id);
4750 } else {
4751 /* Revert to BR/EDR connect */
4752 l2cap_send_conn_req(chan);
4753 }
4754
4755 return;
4756 }
4757
4758 /* Incoming channel on AMP */
4759 if (__l2cap_no_conn_pending(chan)) {
4760 struct l2cap_conn_rsp rsp;
4761 char buf[128];
4762 rsp.scid = cpu_to_le16(chan->dcid);
4763 rsp.dcid = cpu_to_le16(chan->scid);
4764
4765 if (result == L2CAP_CR_SUCCESS) {
4766 /* Send successful response */
4767 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
4768 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
4769 } else {
4770 /* Send negative response */
4771 rsp.result = cpu_to_le16(L2CAP_CR_NO_MEM);
4772 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
4773 }
4774
4775 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_CREATE_CHAN_RSP,
4776 sizeof(rsp), &rsp);
4777
4778 if (result == L2CAP_CR_SUCCESS) {
4779 l2cap_state_change(chan, BT_CONFIG);
4780 set_bit(CONF_REQ_SENT, &chan->conf_state);
4781 l2cap_send_cmd(chan->conn, l2cap_get_ident(chan->conn),
4782 L2CAP_CONF_REQ,
4783 l2cap_build_conf_req(chan, buf), buf);
4784 chan->num_conf_req++;
4785 }
4786 }
4787 }
4788
4789 static void l2cap_do_move_initiate(struct l2cap_chan *chan, u8 local_amp_id,
4790 u8 remote_amp_id)
4791 {
4792 l2cap_move_setup(chan);
4793 chan->move_id = local_amp_id;
4794 chan->move_state = L2CAP_MOVE_WAIT_RSP;
4795
4796 l2cap_send_move_chan_req(chan, remote_amp_id);
4797 }
4798
4799 static void l2cap_do_move_respond(struct l2cap_chan *chan, int result)
4800 {
4801 struct hci_chan *hchan = NULL;
4802
4803 /* Placeholder - get hci_chan for logical link */
4804
4805 if (hchan) {
4806 if (hchan->state == BT_CONNECTED) {
4807 /* Logical link is ready to go */
4808 chan->hs_hcon = hchan->conn;
4809 chan->hs_hcon->l2cap_data = chan->conn;
4810 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
4811 l2cap_send_move_chan_rsp(chan, L2CAP_MR_SUCCESS);
4812
4813 l2cap_logical_cfm(chan, hchan, L2CAP_MR_SUCCESS);
4814 } else {
4815 /* Wait for logical link to be ready */
4816 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
4817 }
4818 } else {
4819 /* Logical link not available */
4820 l2cap_send_move_chan_rsp(chan, L2CAP_MR_NOT_ALLOWED);
4821 }
4822 }
4823
4824 static void l2cap_do_move_cancel(struct l2cap_chan *chan, int result)
4825 {
4826 if (chan->move_role == L2CAP_MOVE_ROLE_RESPONDER) {
4827 u8 rsp_result;
4828 if (result == -EINVAL)
4829 rsp_result = L2CAP_MR_BAD_ID;
4830 else
4831 rsp_result = L2CAP_MR_NOT_ALLOWED;
4832
4833 l2cap_send_move_chan_rsp(chan, rsp_result);
4834 }
4835
4836 chan->move_role = L2CAP_MOVE_ROLE_NONE;
4837 chan->move_state = L2CAP_MOVE_STABLE;
4838
4839 /* Restart data transmission */
4840 l2cap_ertm_send(chan);
4841 }
4842
4843 /* Invoke with locked chan */
4844 void __l2cap_physical_cfm(struct l2cap_chan *chan, int result)
4845 {
4846 u8 local_amp_id = chan->local_amp_id;
4847 u8 remote_amp_id = chan->remote_amp_id;
4848
4849 BT_DBG("chan %p, result %d, local_amp_id %d, remote_amp_id %d",
4850 chan, result, local_amp_id, remote_amp_id);
4851
4852 if (chan->state == BT_DISCONN || chan->state == BT_CLOSED) {
4853 l2cap_chan_unlock(chan);
4854 return;
4855 }
4856
4857 if (chan->state != BT_CONNECTED) {
4858 l2cap_do_create(chan, result, local_amp_id, remote_amp_id);
4859 } else if (result != L2CAP_MR_SUCCESS) {
4860 l2cap_do_move_cancel(chan, result);
4861 } else {
4862 switch (chan->move_role) {
4863 case L2CAP_MOVE_ROLE_INITIATOR:
4864 l2cap_do_move_initiate(chan, local_amp_id,
4865 remote_amp_id);
4866 break;
4867 case L2CAP_MOVE_ROLE_RESPONDER:
4868 l2cap_do_move_respond(chan, result);
4869 break;
4870 default:
4871 l2cap_do_move_cancel(chan, result);
4872 break;
4873 }
4874 }
4875 }
4876
4877 static inline int l2cap_move_channel_req(struct l2cap_conn *conn,
4878 struct l2cap_cmd_hdr *cmd,
4879 u16 cmd_len, void *data)
4880 {
4881 struct l2cap_move_chan_req *req = data;
4882 struct l2cap_move_chan_rsp rsp;
4883 struct l2cap_chan *chan;
4884 u16 icid = 0;
4885 u16 result = L2CAP_MR_NOT_ALLOWED;
4886
4887 if (cmd_len != sizeof(*req))
4888 return -EPROTO;
4889
4890 icid = le16_to_cpu(req->icid);
4891
4892 BT_DBG("icid 0x%4.4x, dest_amp_id %d", icid, req->dest_amp_id);
4893
4894 if (!(conn->local_fixed_chan & L2CAP_FC_A2MP))
4895 return -EINVAL;
4896
4897 chan = l2cap_get_chan_by_dcid(conn, icid);
4898 if (!chan) {
4899 rsp.icid = cpu_to_le16(icid);
4900 rsp.result = cpu_to_le16(L2CAP_MR_NOT_ALLOWED);
4901 l2cap_send_cmd(conn, cmd->ident, L2CAP_MOVE_CHAN_RSP,
4902 sizeof(rsp), &rsp);
4903 return 0;
4904 }
4905
4906 chan->ident = cmd->ident;
4907
4908 if (chan->scid < L2CAP_CID_DYN_START ||
4909 chan->chan_policy == BT_CHANNEL_POLICY_BREDR_ONLY ||
4910 (chan->mode != L2CAP_MODE_ERTM &&
4911 chan->mode != L2CAP_MODE_STREAMING)) {
4912 result = L2CAP_MR_NOT_ALLOWED;
4913 goto send_move_response;
4914 }
4915
4916 if (chan->local_amp_id == req->dest_amp_id) {
4917 result = L2CAP_MR_SAME_ID;
4918 goto send_move_response;
4919 }
4920
4921 if (req->dest_amp_id != AMP_ID_BREDR) {
4922 struct hci_dev *hdev;
4923 hdev = hci_dev_get(req->dest_amp_id);
4924 if (!hdev || hdev->dev_type != HCI_AMP ||
4925 !test_bit(HCI_UP, &hdev->flags)) {
4926 if (hdev)
4927 hci_dev_put(hdev);
4928
4929 result = L2CAP_MR_BAD_ID;
4930 goto send_move_response;
4931 }
4932 hci_dev_put(hdev);
4933 }
4934
4935 /* Detect a move collision. Only send a collision response
4936 * if this side has "lost", otherwise proceed with the move.
4937 * The winner has the larger bd_addr.
4938 */
4939 if ((__chan_is_moving(chan) ||
4940 chan->move_role != L2CAP_MOVE_ROLE_NONE) &&
4941 bacmp(&conn->hcon->src, &conn->hcon->dst) > 0) {
4942 result = L2CAP_MR_COLLISION;
4943 goto send_move_response;
4944 }
4945
4946 chan->move_role = L2CAP_MOVE_ROLE_RESPONDER;
4947 l2cap_move_setup(chan);
4948 chan->move_id = req->dest_amp_id;
4949 icid = chan->dcid;
4950
4951 if (req->dest_amp_id == AMP_ID_BREDR) {
4952 /* Moving to BR/EDR */
4953 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
4954 chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
4955 result = L2CAP_MR_PEND;
4956 } else {
4957 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
4958 result = L2CAP_MR_SUCCESS;
4959 }
4960 } else {
4961 chan->move_state = L2CAP_MOVE_WAIT_PREPARE;
4962 /* Placeholder - uncomment when amp functions are available */
4963 /*amp_accept_physical(chan, req->dest_amp_id);*/
4964 result = L2CAP_MR_PEND;
4965 }
4966
4967 send_move_response:
4968 l2cap_send_move_chan_rsp(chan, result);
4969
4970 l2cap_chan_unlock(chan);
4971
4972 return 0;
4973 }
4974
4975 static void l2cap_move_continue(struct l2cap_conn *conn, u16 icid, u16 result)
4976 {
4977 struct l2cap_chan *chan;
4978 struct hci_chan *hchan = NULL;
4979
4980 chan = l2cap_get_chan_by_scid(conn, icid);
4981 if (!chan) {
4982 l2cap_send_move_chan_cfm_icid(conn, icid);
4983 return;
4984 }
4985
4986 __clear_chan_timer(chan);
4987 if (result == L2CAP_MR_PEND)
4988 __set_chan_timer(chan, L2CAP_MOVE_ERTX_TIMEOUT);
4989
4990 switch (chan->move_state) {
4991 case L2CAP_MOVE_WAIT_LOGICAL_COMP:
4992 /* Move confirm will be sent when logical link
4993 * is complete.
4994 */
4995 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
4996 break;
4997 case L2CAP_MOVE_WAIT_RSP_SUCCESS:
4998 if (result == L2CAP_MR_PEND) {
4999 break;
5000 } else if (test_bit(CONN_LOCAL_BUSY,
5001 &chan->conn_state)) {
5002 chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
5003 } else {
5004 /* Logical link is up or moving to BR/EDR,
5005 * proceed with move
5006 */
5007 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM_RSP;
5008 l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
5009 }
5010 break;
5011 case L2CAP_MOVE_WAIT_RSP:
5012 /* Moving to AMP */
5013 if (result == L2CAP_MR_SUCCESS) {
5014 /* Remote is ready, send confirm immediately
5015 * after logical link is ready
5016 */
5017 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
5018 } else {
5019 /* Both logical link and move success
5020 * are required to confirm
5021 */
5022 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_COMP;
5023 }
5024
5025 /* Placeholder - get hci_chan for logical link */
5026 if (!hchan) {
5027 /* Logical link not available */
5028 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5029 break;
5030 }
5031
5032 /* If the logical link is not yet connected, do not
5033 * send confirmation.
5034 */
5035 if (hchan->state != BT_CONNECTED)
5036 break;
5037
5038 /* Logical link is already ready to go */
5039
5040 chan->hs_hcon = hchan->conn;
5041 chan->hs_hcon->l2cap_data = chan->conn;
5042
5043 if (result == L2CAP_MR_SUCCESS) {
5044 /* Can confirm now */
5045 l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
5046 } else {
5047 /* Now only need move success
5048 * to confirm
5049 */
5050 chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
5051 }
5052
5053 l2cap_logical_cfm(chan, hchan, L2CAP_MR_SUCCESS);
5054 break;
5055 default:
5056 /* Any other amp move state means the move failed. */
5057 chan->move_id = chan->local_amp_id;
5058 l2cap_move_done(chan);
5059 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5060 }
5061
5062 l2cap_chan_unlock(chan);
5063 }
5064
5065 static void l2cap_move_fail(struct l2cap_conn *conn, u8 ident, u16 icid,
5066 u16 result)
5067 {
5068 struct l2cap_chan *chan;
5069
5070 chan = l2cap_get_chan_by_ident(conn, ident);
5071 if (!chan) {
5072 /* Could not locate channel, icid is best guess */
5073 l2cap_send_move_chan_cfm_icid(conn, icid);
5074 return;
5075 }
5076
5077 __clear_chan_timer(chan);
5078
5079 if (chan->move_role == L2CAP_MOVE_ROLE_INITIATOR) {
5080 if (result == L2CAP_MR_COLLISION) {
5081 chan->move_role = L2CAP_MOVE_ROLE_RESPONDER;
5082 } else {
5083 /* Cleanup - cancel move */
5084 chan->move_id = chan->local_amp_id;
5085 l2cap_move_done(chan);
5086 }
5087 }
5088
5089 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5090
5091 l2cap_chan_unlock(chan);
5092 }
5093
5094 static int l2cap_move_channel_rsp(struct l2cap_conn *conn,
5095 struct l2cap_cmd_hdr *cmd,
5096 u16 cmd_len, void *data)
5097 {
5098 struct l2cap_move_chan_rsp *rsp = data;
5099 u16 icid, result;
5100
5101 if (cmd_len != sizeof(*rsp))
5102 return -EPROTO;
5103
5104 icid = le16_to_cpu(rsp->icid);
5105 result = le16_to_cpu(rsp->result);
5106
5107 BT_DBG("icid 0x%4.4x, result 0x%4.4x", icid, result);
5108
5109 if (result == L2CAP_MR_SUCCESS || result == L2CAP_MR_PEND)
5110 l2cap_move_continue(conn, icid, result);
5111 else
5112 l2cap_move_fail(conn, cmd->ident, icid, result);
5113
5114 return 0;
5115 }
5116
5117 static int l2cap_move_channel_confirm(struct l2cap_conn *conn,
5118 struct l2cap_cmd_hdr *cmd,
5119 u16 cmd_len, void *data)
5120 {
5121 struct l2cap_move_chan_cfm *cfm = data;
5122 struct l2cap_chan *chan;
5123 u16 icid, result;
5124
5125 if (cmd_len != sizeof(*cfm))
5126 return -EPROTO;
5127
5128 icid = le16_to_cpu(cfm->icid);
5129 result = le16_to_cpu(cfm->result);
5130
5131 BT_DBG("icid 0x%4.4x, result 0x%4.4x", icid, result);
5132
5133 chan = l2cap_get_chan_by_dcid(conn, icid);
5134 if (!chan) {
5135 /* Spec requires a response even if the icid was not found */
5136 l2cap_send_move_chan_cfm_rsp(conn, cmd->ident, icid);
5137 return 0;
5138 }
5139
5140 if (chan->move_state == L2CAP_MOVE_WAIT_CONFIRM) {
5141 if (result == L2CAP_MC_CONFIRMED) {
5142 chan->local_amp_id = chan->move_id;
5143 if (chan->local_amp_id == AMP_ID_BREDR)
5144 __release_logical_link(chan);
5145 } else {
5146 chan->move_id = chan->local_amp_id;
5147 }
5148
5149 l2cap_move_done(chan);
5150 }
5151
5152 l2cap_send_move_chan_cfm_rsp(conn, cmd->ident, icid);
5153
5154 l2cap_chan_unlock(chan);
5155
5156 return 0;
5157 }
5158
5159 static inline int l2cap_move_channel_confirm_rsp(struct l2cap_conn *conn,
5160 struct l2cap_cmd_hdr *cmd,
5161 u16 cmd_len, void *data)
5162 {
5163 struct l2cap_move_chan_cfm_rsp *rsp = data;
5164 struct l2cap_chan *chan;
5165 u16 icid;
5166
5167 if (cmd_len != sizeof(*rsp))
5168 return -EPROTO;
5169
5170 icid = le16_to_cpu(rsp->icid);
5171
5172 BT_DBG("icid 0x%4.4x", icid);
5173
5174 chan = l2cap_get_chan_by_scid(conn, icid);
5175 if (!chan)
5176 return 0;
5177
5178 __clear_chan_timer(chan);
5179
5180 if (chan->move_state == L2CAP_MOVE_WAIT_CONFIRM_RSP) {
5181 chan->local_amp_id = chan->move_id;
5182
5183 if (chan->local_amp_id == AMP_ID_BREDR && chan->hs_hchan)
5184 __release_logical_link(chan);
5185
5186 l2cap_move_done(chan);
5187 }
5188
5189 l2cap_chan_unlock(chan);
5190
5191 return 0;
5192 }
5193
5194 static inline int l2cap_conn_param_update_req(struct l2cap_conn *conn,
5195 struct l2cap_cmd_hdr *cmd,
5196 u16 cmd_len, u8 *data)
5197 {
5198 struct hci_conn *hcon = conn->hcon;
5199 struct l2cap_conn_param_update_req *req;
5200 struct l2cap_conn_param_update_rsp rsp;
5201 u16 min, max, latency, to_multiplier;
5202 int err;
5203
5204 if (hcon->role != HCI_ROLE_MASTER)
5205 return -EINVAL;
5206
5207 if (cmd_len != sizeof(struct l2cap_conn_param_update_req))
5208 return -EPROTO;
5209
5210 req = (struct l2cap_conn_param_update_req *) data;
5211 min = __le16_to_cpu(req->min);
5212 max = __le16_to_cpu(req->max);
5213 latency = __le16_to_cpu(req->latency);
5214 to_multiplier = __le16_to_cpu(req->to_multiplier);
5215
5216 BT_DBG("min 0x%4.4x max 0x%4.4x latency: 0x%4.4x Timeout: 0x%4.4x",
5217 min, max, latency, to_multiplier);
5218
5219 memset(&rsp, 0, sizeof(rsp));
5220
5221 err = hci_check_conn_params(min, max, latency, to_multiplier);
5222 if (err)
5223 rsp.result = cpu_to_le16(L2CAP_CONN_PARAM_REJECTED);
5224 else
5225 rsp.result = cpu_to_le16(L2CAP_CONN_PARAM_ACCEPTED);
5226
5227 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONN_PARAM_UPDATE_RSP,
5228 sizeof(rsp), &rsp);
5229
5230 if (!err) {
5231 u8 store_hint;
5232
5233 store_hint = hci_le_conn_update(hcon, min, max, latency,
5234 to_multiplier);
5235 mgmt_new_conn_param(hcon->hdev, &hcon->dst, hcon->dst_type,
5236 store_hint, min, max, latency,
5237 to_multiplier);
5238
5239 }
5240
5241 return 0;
5242 }
5243
5244 static int l2cap_le_connect_rsp(struct l2cap_conn *conn,
5245 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5246 u8 *data)
5247 {
5248 struct l2cap_le_conn_rsp *rsp = (struct l2cap_le_conn_rsp *) data;
5249 struct hci_conn *hcon = conn->hcon;
5250 u16 dcid, mtu, mps, credits, result;
5251 struct l2cap_chan *chan;
5252 int err, sec_level;
5253
5254 if (cmd_len < sizeof(*rsp))
5255 return -EPROTO;
5256
5257 dcid = __le16_to_cpu(rsp->dcid);
5258 mtu = __le16_to_cpu(rsp->mtu);
5259 mps = __le16_to_cpu(rsp->mps);
5260 credits = __le16_to_cpu(rsp->credits);
5261 result = __le16_to_cpu(rsp->result);
5262
5263 if (result == L2CAP_CR_SUCCESS && (mtu < 23 || mps < 23 ||
5264 dcid < L2CAP_CID_DYN_START ||
5265 dcid > L2CAP_CID_LE_DYN_END))
5266 return -EPROTO;
5267
5268 BT_DBG("dcid 0x%4.4x mtu %u mps %u credits %u result 0x%2.2x",
5269 dcid, mtu, mps, credits, result);
5270
5271 mutex_lock(&conn->chan_lock);
5272
5273 chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
5274 if (!chan) {
5275 err = -EBADSLT;
5276 goto unlock;
5277 }
5278
5279 err = 0;
5280
5281 l2cap_chan_lock(chan);
5282
5283 switch (result) {
5284 case L2CAP_CR_SUCCESS:
5285 if (__l2cap_get_chan_by_dcid(conn, dcid)) {
5286 err = -EBADSLT;
5287 break;
5288 }
5289
5290 chan->ident = 0;
5291 chan->dcid = dcid;
5292 chan->omtu = mtu;
5293 chan->remote_mps = mps;
5294 chan->tx_credits = credits;
5295 l2cap_chan_ready(chan);
5296 break;
5297
5298 case L2CAP_CR_AUTHENTICATION:
5299 case L2CAP_CR_ENCRYPTION:
5300 /* If we already have MITM protection we can't do
5301 * anything.
5302 */
5303 if (hcon->sec_level > BT_SECURITY_MEDIUM) {
5304 l2cap_chan_del(chan, ECONNREFUSED);
5305 break;
5306 }
5307
5308 sec_level = hcon->sec_level + 1;
5309 if (chan->sec_level < sec_level)
5310 chan->sec_level = sec_level;
5311
5312 /* We'll need to send a new Connect Request */
5313 clear_bit(FLAG_LE_CONN_REQ_SENT, &chan->flags);
5314
5315 smp_conn_security(hcon, chan->sec_level);
5316 break;
5317
5318 default:
5319 l2cap_chan_del(chan, ECONNREFUSED);
5320 break;
5321 }
5322
5323 l2cap_chan_unlock(chan);
5324
5325 unlock:
5326 mutex_unlock(&conn->chan_lock);
5327
5328 return err;
5329 }
5330
5331 static inline int l2cap_bredr_sig_cmd(struct l2cap_conn *conn,
5332 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5333 u8 *data)
5334 {
5335 int err = 0;
5336
5337 switch (cmd->code) {
5338 case L2CAP_COMMAND_REJ:
5339 l2cap_command_rej(conn, cmd, cmd_len, data);
5340 break;
5341
5342 case L2CAP_CONN_REQ:
5343 err = l2cap_connect_req(conn, cmd, cmd_len, data);
5344 break;
5345
5346 case L2CAP_CONN_RSP:
5347 case L2CAP_CREATE_CHAN_RSP:
5348 l2cap_connect_create_rsp(conn, cmd, cmd_len, data);
5349 break;
5350
5351 case L2CAP_CONF_REQ:
5352 err = l2cap_config_req(conn, cmd, cmd_len, data);
5353 break;
5354
5355 case L2CAP_CONF_RSP:
5356 l2cap_config_rsp(conn, cmd, cmd_len, data);
5357 break;
5358
5359 case L2CAP_DISCONN_REQ:
5360 err = l2cap_disconnect_req(conn, cmd, cmd_len, data);
5361 break;
5362
5363 case L2CAP_DISCONN_RSP:
5364 l2cap_disconnect_rsp(conn, cmd, cmd_len, data);
5365 break;
5366
5367 case L2CAP_ECHO_REQ:
5368 l2cap_send_cmd(conn, cmd->ident, L2CAP_ECHO_RSP, cmd_len, data);
5369 break;
5370
5371 case L2CAP_ECHO_RSP:
5372 break;
5373
5374 case L2CAP_INFO_REQ:
5375 err = l2cap_information_req(conn, cmd, cmd_len, data);
5376 break;
5377
5378 case L2CAP_INFO_RSP:
5379 l2cap_information_rsp(conn, cmd, cmd_len, data);
5380 break;
5381
5382 case L2CAP_CREATE_CHAN_REQ:
5383 err = l2cap_create_channel_req(conn, cmd, cmd_len, data);
5384 break;
5385
5386 case L2CAP_MOVE_CHAN_REQ:
5387 err = l2cap_move_channel_req(conn, cmd, cmd_len, data);
5388 break;
5389
5390 case L2CAP_MOVE_CHAN_RSP:
5391 l2cap_move_channel_rsp(conn, cmd, cmd_len, data);
5392 break;
5393
5394 case L2CAP_MOVE_CHAN_CFM:
5395 err = l2cap_move_channel_confirm(conn, cmd, cmd_len, data);
5396 break;
5397
5398 case L2CAP_MOVE_CHAN_CFM_RSP:
5399 l2cap_move_channel_confirm_rsp(conn, cmd, cmd_len, data);
5400 break;
5401
5402 default:
5403 BT_ERR("Unknown BR/EDR signaling command 0x%2.2x", cmd->code);
5404 err = -EINVAL;
5405 break;
5406 }
5407
5408 return err;
5409 }
5410
5411 static int l2cap_le_connect_req(struct l2cap_conn *conn,
5412 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5413 u8 *data)
5414 {
5415 struct l2cap_le_conn_req *req = (struct l2cap_le_conn_req *) data;
5416 struct l2cap_le_conn_rsp rsp;
5417 struct l2cap_chan *chan, *pchan;
5418 u16 dcid, scid, credits, mtu, mps;
5419 __le16 psm;
5420 u8 result;
5421
5422 if (cmd_len != sizeof(*req))
5423 return -EPROTO;
5424
5425 scid = __le16_to_cpu(req->scid);
5426 mtu = __le16_to_cpu(req->mtu);
5427 mps = __le16_to_cpu(req->mps);
5428 psm = req->psm;
5429 dcid = 0;
5430 credits = 0;
5431
5432 if (mtu < 23 || mps < 23)
5433 return -EPROTO;
5434
5435 BT_DBG("psm 0x%2.2x scid 0x%4.4x mtu %u mps %u", __le16_to_cpu(psm),
5436 scid, mtu, mps);
5437
5438 /* Check if we have socket listening on psm */
5439 pchan = l2cap_global_chan_by_psm(BT_LISTEN, psm, &conn->hcon->src,
5440 &conn->hcon->dst, LE_LINK);
5441 if (!pchan) {
5442 result = L2CAP_CR_BAD_PSM;
5443 chan = NULL;
5444 goto response;
5445 }
5446
5447 mutex_lock(&conn->chan_lock);
5448 l2cap_chan_lock(pchan);
5449
5450 if (!smp_sufficient_security(conn->hcon, pchan->sec_level,
5451 SMP_ALLOW_STK)) {
5452 result = L2CAP_CR_AUTHENTICATION;
5453 chan = NULL;
5454 goto response_unlock;
5455 }
5456
5457 /* Check for valid dynamic CID range */
5458 if (scid < L2CAP_CID_DYN_START || scid > L2CAP_CID_LE_DYN_END) {
5459 result = L2CAP_CR_INVALID_SCID;
5460 chan = NULL;
5461 goto response_unlock;
5462 }
5463
5464 /* Check if we already have channel with that dcid */
5465 if (__l2cap_get_chan_by_dcid(conn, scid)) {
5466 result = L2CAP_CR_SCID_IN_USE;
5467 chan = NULL;
5468 goto response_unlock;
5469 }
5470
5471 chan = pchan->ops->new_connection(pchan);
5472 if (!chan) {
5473 result = L2CAP_CR_NO_MEM;
5474 goto response_unlock;
5475 }
5476
5477 l2cap_le_flowctl_init(chan);
5478
5479 bacpy(&chan->src, &conn->hcon->src);
5480 bacpy(&chan->dst, &conn->hcon->dst);
5481 chan->src_type = bdaddr_src_type(conn->hcon);
5482 chan->dst_type = bdaddr_dst_type(conn->hcon);
5483 chan->psm = psm;
5484 chan->dcid = scid;
5485 chan->omtu = mtu;
5486 chan->remote_mps = mps;
5487 chan->tx_credits = __le16_to_cpu(req->credits);
5488
5489 __l2cap_chan_add(conn, chan);
5490 dcid = chan->scid;
5491 credits = chan->rx_credits;
5492
5493 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
5494
5495 chan->ident = cmd->ident;
5496
5497 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
5498 l2cap_state_change(chan, BT_CONNECT2);
5499 /* The following result value is actually not defined
5500 * for LE CoC but we use it to let the function know
5501 * that it should bail out after doing its cleanup
5502 * instead of sending a response.
5503 */
5504 result = L2CAP_CR_PEND;
5505 chan->ops->defer(chan);
5506 } else {
5507 l2cap_chan_ready(chan);
5508 result = L2CAP_CR_SUCCESS;
5509 }
5510
5511 response_unlock:
5512 l2cap_chan_unlock(pchan);
5513 mutex_unlock(&conn->chan_lock);
5514 l2cap_chan_put(pchan);
5515
5516 if (result == L2CAP_CR_PEND)
5517 return 0;
5518
5519 response:
5520 if (chan) {
5521 rsp.mtu = cpu_to_le16(chan->imtu);
5522 rsp.mps = cpu_to_le16(chan->mps);
5523 } else {
5524 rsp.mtu = 0;
5525 rsp.mps = 0;
5526 }
5527
5528 rsp.dcid = cpu_to_le16(dcid);
5529 rsp.credits = cpu_to_le16(credits);
5530 rsp.result = cpu_to_le16(result);
5531
5532 l2cap_send_cmd(conn, cmd->ident, L2CAP_LE_CONN_RSP, sizeof(rsp), &rsp);
5533
5534 return 0;
5535 }
5536
5537 static inline int l2cap_le_credits(struct l2cap_conn *conn,
5538 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5539 u8 *data)
5540 {
5541 struct l2cap_le_credits *pkt;
5542 struct l2cap_chan *chan;
5543 u16 cid, credits, max_credits;
5544
5545 if (cmd_len != sizeof(*pkt))
5546 return -EPROTO;
5547
5548 pkt = (struct l2cap_le_credits *) data;
5549 cid = __le16_to_cpu(pkt->cid);
5550 credits = __le16_to_cpu(pkt->credits);
5551
5552 BT_DBG("cid 0x%4.4x credits 0x%4.4x", cid, credits);
5553
5554 chan = l2cap_get_chan_by_dcid(conn, cid);
5555 if (!chan)
5556 return -EBADSLT;
5557
5558 max_credits = LE_FLOWCTL_MAX_CREDITS - chan->tx_credits;
5559 if (credits > max_credits) {
5560 BT_ERR("LE credits overflow");
5561 l2cap_send_disconn_req(chan, ECONNRESET);
5562 l2cap_chan_unlock(chan);
5563
5564 /* Return 0 so that we don't trigger an unnecessary
5565 * command reject packet.
5566 */
5567 return 0;
5568 }
5569
5570 chan->tx_credits += credits;
5571
5572 while (chan->tx_credits && !skb_queue_empty(&chan->tx_q)) {
5573 l2cap_do_send(chan, skb_dequeue(&chan->tx_q));
5574 chan->tx_credits--;
5575 }
5576
5577 if (chan->tx_credits)
5578 chan->ops->resume(chan);
5579
5580 l2cap_chan_unlock(chan);
5581
5582 return 0;
5583 }
5584
5585 static inline int l2cap_le_command_rej(struct l2cap_conn *conn,
5586 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5587 u8 *data)
5588 {
5589 struct l2cap_cmd_rej_unk *rej = (struct l2cap_cmd_rej_unk *) data;
5590 struct l2cap_chan *chan;
5591
5592 if (cmd_len < sizeof(*rej))
5593 return -EPROTO;
5594
5595 mutex_lock(&conn->chan_lock);
5596
5597 chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
5598 if (!chan)
5599 goto done;
5600
5601 l2cap_chan_lock(chan);
5602 l2cap_chan_del(chan, ECONNREFUSED);
5603 l2cap_chan_unlock(chan);
5604
5605 done:
5606 mutex_unlock(&conn->chan_lock);
5607 return 0;
5608 }
5609
5610 static inline int l2cap_le_sig_cmd(struct l2cap_conn *conn,
5611 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5612 u8 *data)
5613 {
5614 int err = 0;
5615
5616 switch (cmd->code) {
5617 case L2CAP_COMMAND_REJ:
5618 l2cap_le_command_rej(conn, cmd, cmd_len, data);
5619 break;
5620
5621 case L2CAP_CONN_PARAM_UPDATE_REQ:
5622 err = l2cap_conn_param_update_req(conn, cmd, cmd_len, data);
5623 break;
5624
5625 case L2CAP_CONN_PARAM_UPDATE_RSP:
5626 break;
5627
5628 case L2CAP_LE_CONN_RSP:
5629 l2cap_le_connect_rsp(conn, cmd, cmd_len, data);
5630 break;
5631
5632 case L2CAP_LE_CONN_REQ:
5633 err = l2cap_le_connect_req(conn, cmd, cmd_len, data);
5634 break;
5635
5636 case L2CAP_LE_CREDITS:
5637 err = l2cap_le_credits(conn, cmd, cmd_len, data);
5638 break;
5639
5640 case L2CAP_DISCONN_REQ:
5641 err = l2cap_disconnect_req(conn, cmd, cmd_len, data);
5642 break;
5643
5644 case L2CAP_DISCONN_RSP:
5645 l2cap_disconnect_rsp(conn, cmd, cmd_len, data);
5646 break;
5647
5648 default:
5649 BT_ERR("Unknown LE signaling command 0x%2.2x", cmd->code);
5650 err = -EINVAL;
5651 break;
5652 }
5653
5654 return err;
5655 }
5656
5657 static inline void l2cap_le_sig_channel(struct l2cap_conn *conn,
5658 struct sk_buff *skb)
5659 {
5660 struct hci_conn *hcon = conn->hcon;
5661 struct l2cap_cmd_hdr *cmd;
5662 u16 len;
5663 int err;
5664
5665 if (hcon->type != LE_LINK)
5666 goto drop;
5667
5668 if (skb->len < L2CAP_CMD_HDR_SIZE)
5669 goto drop;
5670
5671 cmd = (void *) skb->data;
5672 skb_pull(skb, L2CAP_CMD_HDR_SIZE);
5673
5674 len = le16_to_cpu(cmd->len);
5675
5676 BT_DBG("code 0x%2.2x len %d id 0x%2.2x", cmd->code, len, cmd->ident);
5677
5678 if (len != skb->len || !cmd->ident) {
5679 BT_DBG("corrupted command");
5680 goto drop;
5681 }
5682
5683 err = l2cap_le_sig_cmd(conn, cmd, len, skb->data);
5684 if (err) {
5685 struct l2cap_cmd_rej_unk rej;
5686
5687 BT_ERR("Wrong link type (%d)", err);
5688
5689 rej.reason = cpu_to_le16(L2CAP_REJ_NOT_UNDERSTOOD);
5690 l2cap_send_cmd(conn, cmd->ident, L2CAP_COMMAND_REJ,
5691 sizeof(rej), &rej);
5692 }
5693
5694 drop:
5695 kfree_skb(skb);
5696 }
5697
5698 static inline void l2cap_sig_channel(struct l2cap_conn *conn,
5699 struct sk_buff *skb)
5700 {
5701 struct hci_conn *hcon = conn->hcon;
5702 u8 *data = skb->data;
5703 int len = skb->len;
5704 struct l2cap_cmd_hdr cmd;
5705 int err;
5706
5707 l2cap_raw_recv(conn, skb);
5708
5709 if (hcon->type != ACL_LINK)
5710 goto drop;
5711
5712 while (len >= L2CAP_CMD_HDR_SIZE) {
5713 u16 cmd_len;
5714 memcpy(&cmd, data, L2CAP_CMD_HDR_SIZE);
5715 data += L2CAP_CMD_HDR_SIZE;
5716 len -= L2CAP_CMD_HDR_SIZE;
5717
5718 cmd_len = le16_to_cpu(cmd.len);
5719
5720 BT_DBG("code 0x%2.2x len %d id 0x%2.2x", cmd.code, cmd_len,
5721 cmd.ident);
5722
5723 if (cmd_len > len || !cmd.ident) {
5724 BT_DBG("corrupted command");
5725 break;
5726 }
5727
5728 err = l2cap_bredr_sig_cmd(conn, &cmd, cmd_len, data);
5729 if (err) {
5730 struct l2cap_cmd_rej_unk rej;
5731
5732 BT_ERR("Wrong link type (%d)", err);
5733
5734 rej.reason = cpu_to_le16(L2CAP_REJ_NOT_UNDERSTOOD);
5735 l2cap_send_cmd(conn, cmd.ident, L2CAP_COMMAND_REJ,
5736 sizeof(rej), &rej);
5737 }
5738
5739 data += cmd_len;
5740 len -= cmd_len;
5741 }
5742
5743 drop:
5744 kfree_skb(skb);
5745 }
5746
5747 static int l2cap_check_fcs(struct l2cap_chan *chan, struct sk_buff *skb)
5748 {
5749 u16 our_fcs, rcv_fcs;
5750 int hdr_size;
5751
5752 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
5753 hdr_size = L2CAP_EXT_HDR_SIZE;
5754 else
5755 hdr_size = L2CAP_ENH_HDR_SIZE;
5756
5757 if (chan->fcs == L2CAP_FCS_CRC16) {
5758 skb_trim(skb, skb->len - L2CAP_FCS_SIZE);
5759 rcv_fcs = get_unaligned_le16(skb->data + skb->len);
5760 our_fcs = crc16(0, skb->data - hdr_size, skb->len + hdr_size);
5761
5762 if (our_fcs != rcv_fcs)
5763 return -EBADMSG;
5764 }
5765 return 0;
5766 }
5767
5768 static void l2cap_send_i_or_rr_or_rnr(struct l2cap_chan *chan)
5769 {
5770 struct l2cap_ctrl control;
5771
5772 BT_DBG("chan %p", chan);
5773
5774 memset(&control, 0, sizeof(control));
5775 control.sframe = 1;
5776 control.final = 1;
5777 control.reqseq = chan->buffer_seq;
5778 set_bit(CONN_SEND_FBIT, &chan->conn_state);
5779
5780 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
5781 control.super = L2CAP_SUPER_RNR;
5782 l2cap_send_sframe(chan, &control);
5783 }
5784
5785 if (test_and_clear_bit(CONN_REMOTE_BUSY, &chan->conn_state) &&
5786 chan->unacked_frames > 0)
5787 __set_retrans_timer(chan);
5788
5789 /* Send pending iframes */
5790 l2cap_ertm_send(chan);
5791
5792 if (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state) &&
5793 test_bit(CONN_SEND_FBIT, &chan->conn_state)) {
5794 /* F-bit wasn't sent in an s-frame or i-frame yet, so
5795 * send it now.
5796 */
5797 control.super = L2CAP_SUPER_RR;
5798 l2cap_send_sframe(chan, &control);
5799 }
5800 }
5801
5802 static void append_skb_frag(struct sk_buff *skb, struct sk_buff *new_frag,
5803 struct sk_buff **last_frag)
5804 {
5805 /* skb->len reflects data in skb as well as all fragments
5806 * skb->data_len reflects only data in fragments
5807 */
5808 if (!skb_has_frag_list(skb))
5809 skb_shinfo(skb)->frag_list = new_frag;
5810
5811 new_frag->next = NULL;
5812
5813 (*last_frag)->next = new_frag;
5814 *last_frag = new_frag;
5815
5816 skb->len += new_frag->len;
5817 skb->data_len += new_frag->len;
5818 skb->truesize += new_frag->truesize;
5819 }
5820
5821 static int l2cap_reassemble_sdu(struct l2cap_chan *chan, struct sk_buff *skb,
5822 struct l2cap_ctrl *control)
5823 {
5824 int err = -EINVAL;
5825
5826 switch (control->sar) {
5827 case L2CAP_SAR_UNSEGMENTED:
5828 if (chan->sdu)
5829 break;
5830
5831 err = chan->ops->recv(chan, skb);
5832 break;
5833
5834 case L2CAP_SAR_START:
5835 if (chan->sdu)
5836 break;
5837
5838 chan->sdu_len = get_unaligned_le16(skb->data);
5839 skb_pull(skb, L2CAP_SDULEN_SIZE);
5840
5841 if (chan->sdu_len > chan->imtu) {
5842 err = -EMSGSIZE;
5843 break;
5844 }
5845
5846 if (skb->len >= chan->sdu_len)
5847 break;
5848
5849 chan->sdu = skb;
5850 chan->sdu_last_frag = skb;
5851
5852 skb = NULL;
5853 err = 0;
5854 break;
5855
5856 case L2CAP_SAR_CONTINUE:
5857 if (!chan->sdu)
5858 break;
5859
5860 append_skb_frag(chan->sdu, skb,
5861 &chan->sdu_last_frag);
5862 skb = NULL;
5863
5864 if (chan->sdu->len >= chan->sdu_len)
5865 break;
5866
5867 err = 0;
5868 break;
5869
5870 case L2CAP_SAR_END:
5871 if (!chan->sdu)
5872 break;
5873
5874 append_skb_frag(chan->sdu, skb,
5875 &chan->sdu_last_frag);
5876 skb = NULL;
5877
5878 if (chan->sdu->len != chan->sdu_len)
5879 break;
5880
5881 err = chan->ops->recv(chan, chan->sdu);
5882
5883 if (!err) {
5884 /* Reassembly complete */
5885 chan->sdu = NULL;
5886 chan->sdu_last_frag = NULL;
5887 chan->sdu_len = 0;
5888 }
5889 break;
5890 }
5891
5892 if (err) {
5893 kfree_skb(skb);
5894 kfree_skb(chan->sdu);
5895 chan->sdu = NULL;
5896 chan->sdu_last_frag = NULL;
5897 chan->sdu_len = 0;
5898 }
5899
5900 return err;
5901 }
5902
5903 static int l2cap_resegment(struct l2cap_chan *chan)
5904 {
5905 /* Placeholder */
5906 return 0;
5907 }
5908
5909 void l2cap_chan_busy(struct l2cap_chan *chan, int busy)
5910 {
5911 u8 event;
5912
5913 if (chan->mode != L2CAP_MODE_ERTM)
5914 return;
5915
5916 event = busy ? L2CAP_EV_LOCAL_BUSY_DETECTED : L2CAP_EV_LOCAL_BUSY_CLEAR;
5917 l2cap_tx(chan, NULL, NULL, event);
5918 }
5919
5920 static int l2cap_rx_queued_iframes(struct l2cap_chan *chan)
5921 {
5922 int err = 0;
5923 /* Pass sequential frames to l2cap_reassemble_sdu()
5924 * until a gap is encountered.
5925 */
5926
5927 BT_DBG("chan %p", chan);
5928
5929 while (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
5930 struct sk_buff *skb;
5931 BT_DBG("Searching for skb with txseq %d (queue len %d)",
5932 chan->buffer_seq, skb_queue_len(&chan->srej_q));
5933
5934 skb = l2cap_ertm_seq_in_queue(&chan->srej_q, chan->buffer_seq);
5935
5936 if (!skb)
5937 break;
5938
5939 skb_unlink(skb, &chan->srej_q);
5940 chan->buffer_seq = __next_seq(chan, chan->buffer_seq);
5941 err = l2cap_reassemble_sdu(chan, skb, &bt_cb(skb)->l2cap);
5942 if (err)
5943 break;
5944 }
5945
5946 if (skb_queue_empty(&chan->srej_q)) {
5947 chan->rx_state = L2CAP_RX_STATE_RECV;
5948 l2cap_send_ack(chan);
5949 }
5950
5951 return err;
5952 }
5953
5954 static void l2cap_handle_srej(struct l2cap_chan *chan,
5955 struct l2cap_ctrl *control)
5956 {
5957 struct sk_buff *skb;
5958
5959 BT_DBG("chan %p, control %p", chan, control);
5960
5961 if (control->reqseq == chan->next_tx_seq) {
5962 BT_DBG("Invalid reqseq %d, disconnecting", control->reqseq);
5963 l2cap_send_disconn_req(chan, ECONNRESET);
5964 return;
5965 }
5966
5967 skb = l2cap_ertm_seq_in_queue(&chan->tx_q, control->reqseq);
5968
5969 if (skb == NULL) {
5970 BT_DBG("Seq %d not available for retransmission",
5971 control->reqseq);
5972 return;
5973 }
5974
5975 if (chan->max_tx != 0 && bt_cb(skb)->l2cap.retries >= chan->max_tx) {
5976 BT_DBG("Retry limit exceeded (%d)", chan->max_tx);
5977 l2cap_send_disconn_req(chan, ECONNRESET);
5978 return;
5979 }
5980
5981 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
5982
5983 if (control->poll) {
5984 l2cap_pass_to_tx(chan, control);
5985
5986 set_bit(CONN_SEND_FBIT, &chan->conn_state);
5987 l2cap_retransmit(chan, control);
5988 l2cap_ertm_send(chan);
5989
5990 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F) {
5991 set_bit(CONN_SREJ_ACT, &chan->conn_state);
5992 chan->srej_save_reqseq = control->reqseq;
5993 }
5994 } else {
5995 l2cap_pass_to_tx_fbit(chan, control);
5996
5997 if (control->final) {
5998 if (chan->srej_save_reqseq != control->reqseq ||
5999 !test_and_clear_bit(CONN_SREJ_ACT,
6000 &chan->conn_state))
6001 l2cap_retransmit(chan, control);
6002 } else {
6003 l2cap_retransmit(chan, control);
6004 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F) {
6005 set_bit(CONN_SREJ_ACT, &chan->conn_state);
6006 chan->srej_save_reqseq = control->reqseq;
6007 }
6008 }
6009 }
6010 }
6011
6012 static void l2cap_handle_rej(struct l2cap_chan *chan,
6013 struct l2cap_ctrl *control)
6014 {
6015 struct sk_buff *skb;
6016
6017 BT_DBG("chan %p, control %p", chan, control);
6018
6019 if (control->reqseq == chan->next_tx_seq) {
6020 BT_DBG("Invalid reqseq %d, disconnecting", control->reqseq);
6021 l2cap_send_disconn_req(chan, ECONNRESET);
6022 return;
6023 }
6024
6025 skb = l2cap_ertm_seq_in_queue(&chan->tx_q, control->reqseq);
6026
6027 if (chan->max_tx && skb &&
6028 bt_cb(skb)->l2cap.retries >= chan->max_tx) {
6029 BT_DBG("Retry limit exceeded (%d)", chan->max_tx);
6030 l2cap_send_disconn_req(chan, ECONNRESET);
6031 return;
6032 }
6033
6034 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6035
6036 l2cap_pass_to_tx(chan, control);
6037
6038 if (control->final) {
6039 if (!test_and_clear_bit(CONN_REJ_ACT, &chan->conn_state))
6040 l2cap_retransmit_all(chan, control);
6041 } else {
6042 l2cap_retransmit_all(chan, control);
6043 l2cap_ertm_send(chan);
6044 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F)
6045 set_bit(CONN_REJ_ACT, &chan->conn_state);
6046 }
6047 }
6048
6049 static u8 l2cap_classify_txseq(struct l2cap_chan *chan, u16 txseq)
6050 {
6051 BT_DBG("chan %p, txseq %d", chan, txseq);
6052
6053 BT_DBG("last_acked_seq %d, expected_tx_seq %d", chan->last_acked_seq,
6054 chan->expected_tx_seq);
6055
6056 if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) {
6057 if (__seq_offset(chan, txseq, chan->last_acked_seq) >=
6058 chan->tx_win) {
6059 /* See notes below regarding "double poll" and
6060 * invalid packets.
6061 */
6062 if (chan->tx_win <= ((chan->tx_win_max + 1) >> 1)) {
6063 BT_DBG("Invalid/Ignore - after SREJ");
6064 return L2CAP_TXSEQ_INVALID_IGNORE;
6065 } else {
6066 BT_DBG("Invalid - in window after SREJ sent");
6067 return L2CAP_TXSEQ_INVALID;
6068 }
6069 }
6070
6071 if (chan->srej_list.head == txseq) {
6072 BT_DBG("Expected SREJ");
6073 return L2CAP_TXSEQ_EXPECTED_SREJ;
6074 }
6075
6076 if (l2cap_ertm_seq_in_queue(&chan->srej_q, txseq)) {
6077 BT_DBG("Duplicate SREJ - txseq already stored");
6078 return L2CAP_TXSEQ_DUPLICATE_SREJ;
6079 }
6080
6081 if (l2cap_seq_list_contains(&chan->srej_list, txseq)) {
6082 BT_DBG("Unexpected SREJ - not requested");
6083 return L2CAP_TXSEQ_UNEXPECTED_SREJ;
6084 }
6085 }
6086
6087 if (chan->expected_tx_seq == txseq) {
6088 if (__seq_offset(chan, txseq, chan->last_acked_seq) >=
6089 chan->tx_win) {
6090 BT_DBG("Invalid - txseq outside tx window");
6091 return L2CAP_TXSEQ_INVALID;
6092 } else {
6093 BT_DBG("Expected");
6094 return L2CAP_TXSEQ_EXPECTED;
6095 }
6096 }
6097
6098 if (__seq_offset(chan, txseq, chan->last_acked_seq) <
6099 __seq_offset(chan, chan->expected_tx_seq, chan->last_acked_seq)) {
6100 BT_DBG("Duplicate - expected_tx_seq later than txseq");
6101 return L2CAP_TXSEQ_DUPLICATE;
6102 }
6103
6104 if (__seq_offset(chan, txseq, chan->last_acked_seq) >= chan->tx_win) {
6105 /* A source of invalid packets is a "double poll" condition,
6106 * where delays cause us to send multiple poll packets. If
6107 * the remote stack receives and processes both polls,
6108 * sequence numbers can wrap around in such a way that a
6109 * resent frame has a sequence number that looks like new data
6110 * with a sequence gap. This would trigger an erroneous SREJ
6111 * request.
6112 *
6113 * Fortunately, this is impossible with a tx window that's
6114 * less than half of the maximum sequence number, which allows
6115 * invalid frames to be safely ignored.
6116 *
6117 * With tx window sizes greater than half of the tx window
6118 * maximum, the frame is invalid and cannot be ignored. This
6119 * causes a disconnect.
6120 */
6121
6122 if (chan->tx_win <= ((chan->tx_win_max + 1) >> 1)) {
6123 BT_DBG("Invalid/Ignore - txseq outside tx window");
6124 return L2CAP_TXSEQ_INVALID_IGNORE;
6125 } else {
6126 BT_DBG("Invalid - txseq outside tx window");
6127 return L2CAP_TXSEQ_INVALID;
6128 }
6129 } else {
6130 BT_DBG("Unexpected - txseq indicates missing frames");
6131 return L2CAP_TXSEQ_UNEXPECTED;
6132 }
6133 }
6134
6135 static int l2cap_rx_state_recv(struct l2cap_chan *chan,
6136 struct l2cap_ctrl *control,
6137 struct sk_buff *skb, u8 event)
6138 {
6139 int err = 0;
6140 bool skb_in_use = false;
6141
6142 BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
6143 event);
6144
6145 switch (event) {
6146 case L2CAP_EV_RECV_IFRAME:
6147 switch (l2cap_classify_txseq(chan, control->txseq)) {
6148 case L2CAP_TXSEQ_EXPECTED:
6149 l2cap_pass_to_tx(chan, control);
6150
6151 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
6152 BT_DBG("Busy, discarding expected seq %d",
6153 control->txseq);
6154 break;
6155 }
6156
6157 chan->expected_tx_seq = __next_seq(chan,
6158 control->txseq);
6159
6160 chan->buffer_seq = chan->expected_tx_seq;
6161 skb_in_use = true;
6162
6163 err = l2cap_reassemble_sdu(chan, skb, control);
6164 if (err)
6165 break;
6166
6167 if (control->final) {
6168 if (!test_and_clear_bit(CONN_REJ_ACT,
6169 &chan->conn_state)) {
6170 control->final = 0;
6171 l2cap_retransmit_all(chan, control);
6172 l2cap_ertm_send(chan);
6173 }
6174 }
6175
6176 if (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state))
6177 l2cap_send_ack(chan);
6178 break;
6179 case L2CAP_TXSEQ_UNEXPECTED:
6180 l2cap_pass_to_tx(chan, control);
6181
6182 /* Can't issue SREJ frames in the local busy state.
6183 * Drop this frame, it will be seen as missing
6184 * when local busy is exited.
6185 */
6186 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
6187 BT_DBG("Busy, discarding unexpected seq %d",
6188 control->txseq);
6189 break;
6190 }
6191
6192 /* There was a gap in the sequence, so an SREJ
6193 * must be sent for each missing frame. The
6194 * current frame is stored for later use.
6195 */
6196 skb_queue_tail(&chan->srej_q, skb);
6197 skb_in_use = true;
6198 BT_DBG("Queued %p (queue len %d)", skb,
6199 skb_queue_len(&chan->srej_q));
6200
6201 clear_bit(CONN_SREJ_ACT, &chan->conn_state);
6202 l2cap_seq_list_clear(&chan->srej_list);
6203 l2cap_send_srej(chan, control->txseq);
6204
6205 chan->rx_state = L2CAP_RX_STATE_SREJ_SENT;
6206 break;
6207 case L2CAP_TXSEQ_DUPLICATE:
6208 l2cap_pass_to_tx(chan, control);
6209 break;
6210 case L2CAP_TXSEQ_INVALID_IGNORE:
6211 break;
6212 case L2CAP_TXSEQ_INVALID:
6213 default:
6214 l2cap_send_disconn_req(chan, ECONNRESET);
6215 break;
6216 }
6217 break;
6218 case L2CAP_EV_RECV_RR:
6219 l2cap_pass_to_tx(chan, control);
6220 if (control->final) {
6221 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6222
6223 if (!test_and_clear_bit(CONN_REJ_ACT, &chan->conn_state) &&
6224 !__chan_is_moving(chan)) {
6225 control->final = 0;
6226 l2cap_retransmit_all(chan, control);
6227 }
6228
6229 l2cap_ertm_send(chan);
6230 } else if (control->poll) {
6231 l2cap_send_i_or_rr_or_rnr(chan);
6232 } else {
6233 if (test_and_clear_bit(CONN_REMOTE_BUSY,
6234 &chan->conn_state) &&
6235 chan->unacked_frames)
6236 __set_retrans_timer(chan);
6237
6238 l2cap_ertm_send(chan);
6239 }
6240 break;
6241 case L2CAP_EV_RECV_RNR:
6242 set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6243 l2cap_pass_to_tx(chan, control);
6244 if (control && control->poll) {
6245 set_bit(CONN_SEND_FBIT, &chan->conn_state);
6246 l2cap_send_rr_or_rnr(chan, 0);
6247 }
6248 __clear_retrans_timer(chan);
6249 l2cap_seq_list_clear(&chan->retrans_list);
6250 break;
6251 case L2CAP_EV_RECV_REJ:
6252 l2cap_handle_rej(chan, control);
6253 break;
6254 case L2CAP_EV_RECV_SREJ:
6255 l2cap_handle_srej(chan, control);
6256 break;
6257 default:
6258 break;
6259 }
6260
6261 if (skb && !skb_in_use) {
6262 BT_DBG("Freeing %p", skb);
6263 kfree_skb(skb);
6264 }
6265
6266 return err;
6267 }
6268
6269 static int l2cap_rx_state_srej_sent(struct l2cap_chan *chan,
6270 struct l2cap_ctrl *control,
6271 struct sk_buff *skb, u8 event)
6272 {
6273 int err = 0;
6274 u16 txseq = control->txseq;
6275 bool skb_in_use = false;
6276
6277 BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
6278 event);
6279
6280 switch (event) {
6281 case L2CAP_EV_RECV_IFRAME:
6282 switch (l2cap_classify_txseq(chan, txseq)) {
6283 case L2CAP_TXSEQ_EXPECTED:
6284 /* Keep frame for reassembly later */
6285 l2cap_pass_to_tx(chan, control);
6286 skb_queue_tail(&chan->srej_q, skb);
6287 skb_in_use = true;
6288 BT_DBG("Queued %p (queue len %d)", skb,
6289 skb_queue_len(&chan->srej_q));
6290
6291 chan->expected_tx_seq = __next_seq(chan, txseq);
6292 break;
6293 case L2CAP_TXSEQ_EXPECTED_SREJ:
6294 l2cap_seq_list_pop(&chan->srej_list);
6295
6296 l2cap_pass_to_tx(chan, control);
6297 skb_queue_tail(&chan->srej_q, skb);
6298 skb_in_use = true;
6299 BT_DBG("Queued %p (queue len %d)", skb,
6300 skb_queue_len(&chan->srej_q));
6301
6302 err = l2cap_rx_queued_iframes(chan);
6303 if (err)
6304 break;
6305
6306 break;
6307 case L2CAP_TXSEQ_UNEXPECTED:
6308 /* Got a frame that can't be reassembled yet.
6309 * Save it for later, and send SREJs to cover
6310 * the missing frames.
6311 */
6312 skb_queue_tail(&chan->srej_q, skb);
6313 skb_in_use = true;
6314 BT_DBG("Queued %p (queue len %d)", skb,
6315 skb_queue_len(&chan->srej_q));
6316
6317 l2cap_pass_to_tx(chan, control);
6318 l2cap_send_srej(chan, control->txseq);
6319 break;
6320 case L2CAP_TXSEQ_UNEXPECTED_SREJ:
6321 /* This frame was requested with an SREJ, but
6322 * some expected retransmitted frames are
6323 * missing. Request retransmission of missing
6324 * SREJ'd frames.
6325 */
6326 skb_queue_tail(&chan->srej_q, skb);
6327 skb_in_use = true;
6328 BT_DBG("Queued %p (queue len %d)", skb,
6329 skb_queue_len(&chan->srej_q));
6330
6331 l2cap_pass_to_tx(chan, control);
6332 l2cap_send_srej_list(chan, control->txseq);
6333 break;
6334 case L2CAP_TXSEQ_DUPLICATE_SREJ:
6335 /* We've already queued this frame. Drop this copy. */
6336 l2cap_pass_to_tx(chan, control);
6337 break;
6338 case L2CAP_TXSEQ_DUPLICATE:
6339 /* Expecting a later sequence number, so this frame
6340 * was already received. Ignore it completely.
6341 */
6342 break;
6343 case L2CAP_TXSEQ_INVALID_IGNORE:
6344 break;
6345 case L2CAP_TXSEQ_INVALID:
6346 default:
6347 l2cap_send_disconn_req(chan, ECONNRESET);
6348 break;
6349 }
6350 break;
6351 case L2CAP_EV_RECV_RR:
6352 l2cap_pass_to_tx(chan, control);
6353 if (control->final) {
6354 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6355
6356 if (!test_and_clear_bit(CONN_REJ_ACT,
6357 &chan->conn_state)) {
6358 control->final = 0;
6359 l2cap_retransmit_all(chan, control);
6360 }
6361
6362 l2cap_ertm_send(chan);
6363 } else if (control->poll) {
6364 if (test_and_clear_bit(CONN_REMOTE_BUSY,
6365 &chan->conn_state) &&
6366 chan->unacked_frames) {
6367 __set_retrans_timer(chan);
6368 }
6369
6370 set_bit(CONN_SEND_FBIT, &chan->conn_state);
6371 l2cap_send_srej_tail(chan);
6372 } else {
6373 if (test_and_clear_bit(CONN_REMOTE_BUSY,
6374 &chan->conn_state) &&
6375 chan->unacked_frames)
6376 __set_retrans_timer(chan);
6377
6378 l2cap_send_ack(chan);
6379 }
6380 break;
6381 case L2CAP_EV_RECV_RNR:
6382 set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6383 l2cap_pass_to_tx(chan, control);
6384 if (control->poll) {
6385 l2cap_send_srej_tail(chan);
6386 } else {
6387 struct l2cap_ctrl rr_control;
6388 memset(&rr_control, 0, sizeof(rr_control));
6389 rr_control.sframe = 1;
6390 rr_control.super = L2CAP_SUPER_RR;
6391 rr_control.reqseq = chan->buffer_seq;
6392 l2cap_send_sframe(chan, &rr_control);
6393 }
6394
6395 break;
6396 case L2CAP_EV_RECV_REJ:
6397 l2cap_handle_rej(chan, control);
6398 break;
6399 case L2CAP_EV_RECV_SREJ:
6400 l2cap_handle_srej(chan, control);
6401 break;
6402 }
6403
6404 if (skb && !skb_in_use) {
6405 BT_DBG("Freeing %p", skb);
6406 kfree_skb(skb);
6407 }
6408
6409 return err;
6410 }
6411
6412 static int l2cap_finish_move(struct l2cap_chan *chan)
6413 {
6414 BT_DBG("chan %p", chan);
6415
6416 chan->rx_state = L2CAP_RX_STATE_RECV;
6417
6418 if (chan->hs_hcon)
6419 chan->conn->mtu = chan->hs_hcon->hdev->block_mtu;
6420 else
6421 chan->conn->mtu = chan->conn->hcon->hdev->acl_mtu;
6422
6423 return l2cap_resegment(chan);
6424 }
6425
6426 static int l2cap_rx_state_wait_p(struct l2cap_chan *chan,
6427 struct l2cap_ctrl *control,
6428 struct sk_buff *skb, u8 event)
6429 {
6430 int err;
6431
6432 BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
6433 event);
6434
6435 if (!control->poll)
6436 return -EPROTO;
6437
6438 l2cap_process_reqseq(chan, control->reqseq);
6439
6440 if (!skb_queue_empty(&chan->tx_q))
6441 chan->tx_send_head = skb_peek(&chan->tx_q);
6442 else
6443 chan->tx_send_head = NULL;
6444
6445 /* Rewind next_tx_seq to the point expected
6446 * by the receiver.
6447 */
6448 chan->next_tx_seq = control->reqseq;
6449 chan->unacked_frames = 0;
6450
6451 err = l2cap_finish_move(chan);
6452 if (err)
6453 return err;
6454
6455 set_bit(CONN_SEND_FBIT, &chan->conn_state);
6456 l2cap_send_i_or_rr_or_rnr(chan);
6457
6458 if (event == L2CAP_EV_RECV_IFRAME)
6459 return -EPROTO;
6460
6461 return l2cap_rx_state_recv(chan, control, NULL, event);
6462 }
6463
6464 static int l2cap_rx_state_wait_f(struct l2cap_chan *chan,
6465 struct l2cap_ctrl *control,
6466 struct sk_buff *skb, u8 event)
6467 {
6468 int err;
6469
6470 if (!control->final)
6471 return -EPROTO;
6472
6473 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6474
6475 chan->rx_state = L2CAP_RX_STATE_RECV;
6476 l2cap_process_reqseq(chan, control->reqseq);
6477
6478 if (!skb_queue_empty(&chan->tx_q))
6479 chan->tx_send_head = skb_peek(&chan->tx_q);
6480 else
6481 chan->tx_send_head = NULL;
6482
6483 /* Rewind next_tx_seq to the point expected
6484 * by the receiver.
6485 */
6486 chan->next_tx_seq = control->reqseq;
6487 chan->unacked_frames = 0;
6488
6489 if (chan->hs_hcon)
6490 chan->conn->mtu = chan->hs_hcon->hdev->block_mtu;
6491 else
6492 chan->conn->mtu = chan->conn->hcon->hdev->acl_mtu;
6493
6494 err = l2cap_resegment(chan);
6495
6496 if (!err)
6497 err = l2cap_rx_state_recv(chan, control, skb, event);
6498
6499 return err;
6500 }
6501
6502 static bool __valid_reqseq(struct l2cap_chan *chan, u16 reqseq)
6503 {
6504 /* Make sure reqseq is for a packet that has been sent but not acked */
6505 u16 unacked;
6506
6507 unacked = __seq_offset(chan, chan->next_tx_seq, chan->expected_ack_seq);
6508 return __seq_offset(chan, chan->next_tx_seq, reqseq) <= unacked;
6509 }
6510
6511 static int l2cap_rx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
6512 struct sk_buff *skb, u8 event)
6513 {
6514 int err = 0;
6515
6516 BT_DBG("chan %p, control %p, skb %p, event %d, state %d", chan,
6517 control, skb, event, chan->rx_state);
6518
6519 if (__valid_reqseq(chan, control->reqseq)) {
6520 switch (chan->rx_state) {
6521 case L2CAP_RX_STATE_RECV:
6522 err = l2cap_rx_state_recv(chan, control, skb, event);
6523 break;
6524 case L2CAP_RX_STATE_SREJ_SENT:
6525 err = l2cap_rx_state_srej_sent(chan, control, skb,
6526 event);
6527 break;
6528 case L2CAP_RX_STATE_WAIT_P:
6529 err = l2cap_rx_state_wait_p(chan, control, skb, event);
6530 break;
6531 case L2CAP_RX_STATE_WAIT_F:
6532 err = l2cap_rx_state_wait_f(chan, control, skb, event);
6533 break;
6534 default:
6535 /* shut it down */
6536 break;
6537 }
6538 } else {
6539 BT_DBG("Invalid reqseq %d (next_tx_seq %d, expected_ack_seq %d",
6540 control->reqseq, chan->next_tx_seq,
6541 chan->expected_ack_seq);
6542 l2cap_send_disconn_req(chan, ECONNRESET);
6543 }
6544
6545 return err;
6546 }
6547
6548 static int l2cap_stream_rx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
6549 struct sk_buff *skb)
6550 {
6551 BT_DBG("chan %p, control %p, skb %p, state %d", chan, control, skb,
6552 chan->rx_state);
6553
6554 if (l2cap_classify_txseq(chan, control->txseq) ==
6555 L2CAP_TXSEQ_EXPECTED) {
6556 l2cap_pass_to_tx(chan, control);
6557
6558 BT_DBG("buffer_seq %d->%d", chan->buffer_seq,
6559 __next_seq(chan, chan->buffer_seq));
6560
6561 chan->buffer_seq = __next_seq(chan, chan->buffer_seq);
6562
6563 l2cap_reassemble_sdu(chan, skb, control);
6564 } else {
6565 if (chan->sdu) {
6566 kfree_skb(chan->sdu);
6567 chan->sdu = NULL;
6568 }
6569 chan->sdu_last_frag = NULL;
6570 chan->sdu_len = 0;
6571
6572 if (skb) {
6573 BT_DBG("Freeing %p", skb);
6574 kfree_skb(skb);
6575 }
6576 }
6577
6578 chan->last_acked_seq = control->txseq;
6579 chan->expected_tx_seq = __next_seq(chan, control->txseq);
6580
6581 return 0;
6582 }
6583
6584 static int l2cap_data_rcv(struct l2cap_chan *chan, struct sk_buff *skb)
6585 {
6586 struct l2cap_ctrl *control = &bt_cb(skb)->l2cap;
6587 u16 len;
6588 u8 event;
6589
6590 __unpack_control(chan, skb);
6591
6592 len = skb->len;
6593
6594 /*
6595 * We can just drop the corrupted I-frame here.
6596 * Receiver will miss it and start proper recovery
6597 * procedures and ask for retransmission.
6598 */
6599 if (l2cap_check_fcs(chan, skb))
6600 goto drop;
6601
6602 if (!control->sframe && control->sar == L2CAP_SAR_START)
6603 len -= L2CAP_SDULEN_SIZE;
6604
6605 if (chan->fcs == L2CAP_FCS_CRC16)
6606 len -= L2CAP_FCS_SIZE;
6607
6608 if (len > chan->mps) {
6609 l2cap_send_disconn_req(chan, ECONNRESET);
6610 goto drop;
6611 }
6612
6613 if (!control->sframe) {
6614 int err;
6615
6616 BT_DBG("iframe sar %d, reqseq %d, final %d, txseq %d",
6617 control->sar, control->reqseq, control->final,
6618 control->txseq);
6619
6620 /* Validate F-bit - F=0 always valid, F=1 only
6621 * valid in TX WAIT_F
6622 */
6623 if (control->final && chan->tx_state != L2CAP_TX_STATE_WAIT_F)
6624 goto drop;
6625
6626 if (chan->mode != L2CAP_MODE_STREAMING) {
6627 event = L2CAP_EV_RECV_IFRAME;
6628 err = l2cap_rx(chan, control, skb, event);
6629 } else {
6630 err = l2cap_stream_rx(chan, control, skb);
6631 }
6632
6633 if (err)
6634 l2cap_send_disconn_req(chan, ECONNRESET);
6635 } else {
6636 const u8 rx_func_to_event[4] = {
6637 L2CAP_EV_RECV_RR, L2CAP_EV_RECV_REJ,
6638 L2CAP_EV_RECV_RNR, L2CAP_EV_RECV_SREJ
6639 };
6640
6641 /* Only I-frames are expected in streaming mode */
6642 if (chan->mode == L2CAP_MODE_STREAMING)
6643 goto drop;
6644
6645 BT_DBG("sframe reqseq %d, final %d, poll %d, super %d",
6646 control->reqseq, control->final, control->poll,
6647 control->super);
6648
6649 if (len != 0) {
6650 BT_ERR("Trailing bytes: %d in sframe", len);
6651 l2cap_send_disconn_req(chan, ECONNRESET);
6652 goto drop;
6653 }
6654
6655 /* Validate F and P bits */
6656 if (control->final && (control->poll ||
6657 chan->tx_state != L2CAP_TX_STATE_WAIT_F))
6658 goto drop;
6659
6660 event = rx_func_to_event[control->super];
6661 if (l2cap_rx(chan, control, skb, event))
6662 l2cap_send_disconn_req(chan, ECONNRESET);
6663 }
6664
6665 return 0;
6666
6667 drop:
6668 kfree_skb(skb);
6669 return 0;
6670 }
6671
6672 static void l2cap_chan_le_send_credits(struct l2cap_chan *chan)
6673 {
6674 struct l2cap_conn *conn = chan->conn;
6675 struct l2cap_le_credits pkt;
6676 u16 return_credits;
6677
6678 /* We return more credits to the sender only after the amount of
6679 * credits falls below half of the initial amount.
6680 */
6681 if (chan->rx_credits >= (le_max_credits + 1) / 2)
6682 return;
6683
6684 return_credits = le_max_credits - chan->rx_credits;
6685
6686 BT_DBG("chan %p returning %u credits to sender", chan, return_credits);
6687
6688 chan->rx_credits += return_credits;
6689
6690 pkt.cid = cpu_to_le16(chan->scid);
6691 pkt.credits = cpu_to_le16(return_credits);
6692
6693 chan->ident = l2cap_get_ident(conn);
6694
6695 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CREDITS, sizeof(pkt), &pkt);
6696 }
6697
6698 static int l2cap_le_data_rcv(struct l2cap_chan *chan, struct sk_buff *skb)
6699 {
6700 int err;
6701
6702 if (!chan->rx_credits) {
6703 BT_ERR("No credits to receive LE L2CAP data");
6704 l2cap_send_disconn_req(chan, ECONNRESET);
6705 return -ENOBUFS;
6706 }
6707
6708 if (chan->imtu < skb->len) {
6709 BT_ERR("Too big LE L2CAP PDU");
6710 return -ENOBUFS;
6711 }
6712
6713 chan->rx_credits--;
6714 BT_DBG("rx_credits %u -> %u", chan->rx_credits + 1, chan->rx_credits);
6715
6716 l2cap_chan_le_send_credits(chan);
6717
6718 err = 0;
6719
6720 if (!chan->sdu) {
6721 u16 sdu_len;
6722
6723 sdu_len = get_unaligned_le16(skb->data);
6724 skb_pull(skb, L2CAP_SDULEN_SIZE);
6725
6726 BT_DBG("Start of new SDU. sdu_len %u skb->len %u imtu %u",
6727 sdu_len, skb->len, chan->imtu);
6728
6729 if (sdu_len > chan->imtu) {
6730 BT_ERR("Too big LE L2CAP SDU length received");
6731 err = -EMSGSIZE;
6732 goto failed;
6733 }
6734
6735 if (skb->len > sdu_len) {
6736 BT_ERR("Too much LE L2CAP data received");
6737 err = -EINVAL;
6738 goto failed;
6739 }
6740
6741 if (skb->len == sdu_len)
6742 return chan->ops->recv(chan, skb);
6743
6744 chan->sdu = skb;
6745 chan->sdu_len = sdu_len;
6746 chan->sdu_last_frag = skb;
6747
6748 return 0;
6749 }
6750
6751 BT_DBG("SDU fragment. chan->sdu->len %u skb->len %u chan->sdu_len %u",
6752 chan->sdu->len, skb->len, chan->sdu_len);
6753
6754 if (chan->sdu->len + skb->len > chan->sdu_len) {
6755 BT_ERR("Too much LE L2CAP data received");
6756 err = -EINVAL;
6757 goto failed;
6758 }
6759
6760 append_skb_frag(chan->sdu, skb, &chan->sdu_last_frag);
6761 skb = NULL;
6762
6763 if (chan->sdu->len == chan->sdu_len) {
6764 err = chan->ops->recv(chan, chan->sdu);
6765 if (!err) {
6766 chan->sdu = NULL;
6767 chan->sdu_last_frag = NULL;
6768 chan->sdu_len = 0;
6769 }
6770 }
6771
6772 failed:
6773 if (err) {
6774 kfree_skb(skb);
6775 kfree_skb(chan->sdu);
6776 chan->sdu = NULL;
6777 chan->sdu_last_frag = NULL;
6778 chan->sdu_len = 0;
6779 }
6780
6781 /* We can't return an error here since we took care of the skb
6782 * freeing internally. An error return would cause the caller to
6783 * do a double-free of the skb.
6784 */
6785 return 0;
6786 }
6787
6788 static void l2cap_data_channel(struct l2cap_conn *conn, u16 cid,
6789 struct sk_buff *skb)
6790 {
6791 struct l2cap_chan *chan;
6792
6793 chan = l2cap_get_chan_by_scid(conn, cid);
6794 if (!chan) {
6795 if (cid == L2CAP_CID_A2MP) {
6796 chan = a2mp_channel_create(conn, skb);
6797 if (!chan) {
6798 kfree_skb(skb);
6799 return;
6800 }
6801
6802 l2cap_chan_lock(chan);
6803 } else {
6804 BT_DBG("unknown cid 0x%4.4x", cid);
6805 /* Drop packet and return */
6806 kfree_skb(skb);
6807 return;
6808 }
6809 }
6810
6811 BT_DBG("chan %p, len %d", chan, skb->len);
6812
6813 /* If we receive data on a fixed channel before the info req/rsp
6814 * procdure is done simply assume that the channel is supported
6815 * and mark it as ready.
6816 */
6817 if (chan->chan_type == L2CAP_CHAN_FIXED)
6818 l2cap_chan_ready(chan);
6819
6820 if (chan->state != BT_CONNECTED)
6821 goto drop;
6822
6823 switch (chan->mode) {
6824 case L2CAP_MODE_LE_FLOWCTL:
6825 if (l2cap_le_data_rcv(chan, skb) < 0)
6826 goto drop;
6827
6828 goto done;
6829
6830 case L2CAP_MODE_BASIC:
6831 /* If socket recv buffers overflows we drop data here
6832 * which is *bad* because L2CAP has to be reliable.
6833 * But we don't have any other choice. L2CAP doesn't
6834 * provide flow control mechanism. */
6835
6836 if (chan->imtu < skb->len) {
6837 BT_ERR("Dropping L2CAP data: receive buffer overflow");
6838 goto drop;
6839 }
6840
6841 if (!chan->ops->recv(chan, skb))
6842 goto done;
6843 break;
6844
6845 case L2CAP_MODE_ERTM:
6846 case L2CAP_MODE_STREAMING:
6847 l2cap_data_rcv(chan, skb);
6848 goto done;
6849
6850 default:
6851 BT_DBG("chan %p: bad mode 0x%2.2x", chan, chan->mode);
6852 break;
6853 }
6854
6855 drop:
6856 kfree_skb(skb);
6857
6858 done:
6859 l2cap_chan_unlock(chan);
6860 }
6861
6862 static void l2cap_conless_channel(struct l2cap_conn *conn, __le16 psm,
6863 struct sk_buff *skb)
6864 {
6865 struct hci_conn *hcon = conn->hcon;
6866 struct l2cap_chan *chan;
6867
6868 if (hcon->type != ACL_LINK)
6869 goto free_skb;
6870
6871 chan = l2cap_global_chan_by_psm(0, psm, &hcon->src, &hcon->dst,
6872 ACL_LINK);
6873 if (!chan)
6874 goto free_skb;
6875
6876 BT_DBG("chan %p, len %d", chan, skb->len);
6877
6878 if (chan->state != BT_BOUND && chan->state != BT_CONNECTED)
6879 goto drop;
6880
6881 if (chan->imtu < skb->len)
6882 goto drop;
6883
6884 /* Store remote BD_ADDR and PSM for msg_name */
6885 bacpy(&bt_cb(skb)->l2cap.bdaddr, &hcon->dst);
6886 bt_cb(skb)->l2cap.psm = psm;
6887
6888 if (!chan->ops->recv(chan, skb)) {
6889 l2cap_chan_put(chan);
6890 return;
6891 }
6892
6893 drop:
6894 l2cap_chan_put(chan);
6895 free_skb:
6896 kfree_skb(skb);
6897 }
6898
6899 static void l2cap_recv_frame(struct l2cap_conn *conn, struct sk_buff *skb)
6900 {
6901 struct l2cap_hdr *lh = (void *) skb->data;
6902 struct hci_conn *hcon = conn->hcon;
6903 u16 cid, len;
6904 __le16 psm;
6905
6906 if (hcon->state != BT_CONNECTED) {
6907 BT_DBG("queueing pending rx skb");
6908 skb_queue_tail(&conn->pending_rx, skb);
6909 return;
6910 }
6911
6912 skb_pull(skb, L2CAP_HDR_SIZE);
6913 cid = __le16_to_cpu(lh->cid);
6914 len = __le16_to_cpu(lh->len);
6915
6916 if (len != skb->len) {
6917 kfree_skb(skb);
6918 return;
6919 }
6920
6921 /* Since we can't actively block incoming LE connections we must
6922 * at least ensure that we ignore incoming data from them.
6923 */
6924 if (hcon->type == LE_LINK &&
6925 hci_bdaddr_list_lookup(&hcon->hdev->blacklist, &hcon->dst,
6926 bdaddr_dst_type(hcon))) {
6927 kfree_skb(skb);
6928 return;
6929 }
6930
6931 BT_DBG("len %d, cid 0x%4.4x", len, cid);
6932
6933 switch (cid) {
6934 case L2CAP_CID_SIGNALING:
6935 l2cap_sig_channel(conn, skb);
6936 break;
6937
6938 case L2CAP_CID_CONN_LESS:
6939 psm = get_unaligned((__le16 *) skb->data);
6940 skb_pull(skb, L2CAP_PSMLEN_SIZE);
6941 l2cap_conless_channel(conn, psm, skb);
6942 break;
6943
6944 case L2CAP_CID_LE_SIGNALING:
6945 l2cap_le_sig_channel(conn, skb);
6946 break;
6947
6948 default:
6949 l2cap_data_channel(conn, cid, skb);
6950 break;
6951 }
6952 }
6953
6954 static void process_pending_rx(struct work_struct *work)
6955 {
6956 struct l2cap_conn *conn = container_of(work, struct l2cap_conn,
6957 pending_rx_work);
6958 struct sk_buff *skb;
6959
6960 BT_DBG("");
6961
6962 while ((skb = skb_dequeue(&conn->pending_rx)))
6963 l2cap_recv_frame(conn, skb);
6964 }
6965
6966 static struct l2cap_conn *l2cap_conn_add(struct hci_conn *hcon)
6967 {
6968 struct l2cap_conn *conn = hcon->l2cap_data;
6969 struct hci_chan *hchan;
6970
6971 if (conn)
6972 return conn;
6973
6974 hchan = hci_chan_create(hcon);
6975 if (!hchan)
6976 return NULL;
6977
6978 conn = kzalloc(sizeof(*conn), GFP_KERNEL);
6979 if (!conn) {
6980 hci_chan_del(hchan);
6981 return NULL;
6982 }
6983
6984 kref_init(&conn->ref);
6985 hcon->l2cap_data = conn;
6986 conn->hcon = hci_conn_get(hcon);
6987 conn->hchan = hchan;
6988
6989 BT_DBG("hcon %p conn %p hchan %p", hcon, conn, hchan);
6990
6991 switch (hcon->type) {
6992 case LE_LINK:
6993 if (hcon->hdev->le_mtu) {
6994 conn->mtu = hcon->hdev->le_mtu;
6995 break;
6996 }
6997 /* fall through */
6998 default:
6999 conn->mtu = hcon->hdev->acl_mtu;
7000 break;
7001 }
7002
7003 conn->feat_mask = 0;
7004
7005 conn->local_fixed_chan = L2CAP_FC_SIG_BREDR | L2CAP_FC_CONNLESS;
7006
7007 if (hcon->type == ACL_LINK &&
7008 hci_dev_test_flag(hcon->hdev, HCI_HS_ENABLED))
7009 conn->local_fixed_chan |= L2CAP_FC_A2MP;
7010
7011 if (hci_dev_test_flag(hcon->hdev, HCI_LE_ENABLED) &&
7012 (bredr_sc_enabled(hcon->hdev) ||
7013 hci_dev_test_flag(hcon->hdev, HCI_FORCE_BREDR_SMP)))
7014 conn->local_fixed_chan |= L2CAP_FC_SMP_BREDR;
7015
7016 mutex_init(&conn->ident_lock);
7017 mutex_init(&conn->chan_lock);
7018
7019 INIT_LIST_HEAD(&conn->chan_l);
7020 INIT_LIST_HEAD(&conn->users);
7021
7022 INIT_DELAYED_WORK(&conn->info_timer, l2cap_info_timeout);
7023
7024 skb_queue_head_init(&conn->pending_rx);
7025 INIT_WORK(&conn->pending_rx_work, process_pending_rx);
7026 INIT_WORK(&conn->id_addr_update_work, l2cap_conn_update_id_addr);
7027
7028 conn->disc_reason = HCI_ERROR_REMOTE_USER_TERM;
7029
7030 return conn;
7031 }
7032
7033 static bool is_valid_psm(u16 psm, u8 dst_type) {
7034 if (!psm)
7035 return false;
7036
7037 if (bdaddr_type_is_le(dst_type))
7038 return (psm <= 0x00ff);
7039
7040 /* PSM must be odd and lsb of upper byte must be 0 */
7041 return ((psm & 0x0101) == 0x0001);
7042 }
7043
7044 int l2cap_chan_connect(struct l2cap_chan *chan, __le16 psm, u16 cid,
7045 bdaddr_t *dst, u8 dst_type)
7046 {
7047 struct l2cap_conn *conn;
7048 struct hci_conn *hcon;
7049 struct hci_dev *hdev;
7050 int err;
7051
7052 BT_DBG("%pMR -> %pMR (type %u) psm 0x%2.2x", &chan->src, dst,
7053 dst_type, __le16_to_cpu(psm));
7054
7055 hdev = hci_get_route(dst, &chan->src);
7056 if (!hdev)
7057 return -EHOSTUNREACH;
7058
7059 hci_dev_lock(hdev);
7060
7061 if (!is_valid_psm(__le16_to_cpu(psm), dst_type) && !cid &&
7062 chan->chan_type != L2CAP_CHAN_RAW) {
7063 err = -EINVAL;
7064 goto done;
7065 }
7066
7067 if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED && !psm) {
7068 err = -EINVAL;
7069 goto done;
7070 }
7071
7072 if (chan->chan_type == L2CAP_CHAN_FIXED && !cid) {
7073 err = -EINVAL;
7074 goto done;
7075 }
7076
7077 switch (chan->mode) {
7078 case L2CAP_MODE_BASIC:
7079 break;
7080 case L2CAP_MODE_LE_FLOWCTL:
7081 l2cap_le_flowctl_init(chan);
7082 break;
7083 case L2CAP_MODE_ERTM:
7084 case L2CAP_MODE_STREAMING:
7085 if (!disable_ertm)
7086 break;
7087 /* fall through */
7088 default:
7089 err = -EOPNOTSUPP;
7090 goto done;
7091 }
7092
7093 switch (chan->state) {
7094 case BT_CONNECT:
7095 case BT_CONNECT2:
7096 case BT_CONFIG:
7097 /* Already connecting */
7098 err = 0;
7099 goto done;
7100
7101 case BT_CONNECTED:
7102 /* Already connected */
7103 err = -EISCONN;
7104 goto done;
7105
7106 case BT_OPEN:
7107 case BT_BOUND:
7108 /* Can connect */
7109 break;
7110
7111 default:
7112 err = -EBADFD;
7113 goto done;
7114 }
7115
7116 /* Set destination address and psm */
7117 bacpy(&chan->dst, dst);
7118 chan->dst_type = dst_type;
7119
7120 chan->psm = psm;
7121 chan->dcid = cid;
7122
7123 if (bdaddr_type_is_le(dst_type)) {
7124 /* Convert from L2CAP channel address type to HCI address type
7125 */
7126 if (dst_type == BDADDR_LE_PUBLIC)
7127 dst_type = ADDR_LE_DEV_PUBLIC;
7128 else
7129 dst_type = ADDR_LE_DEV_RANDOM;
7130
7131 if (hci_dev_test_flag(hdev, HCI_ADVERTISING))
7132 hcon = hci_connect_le(hdev, dst, dst_type,
7133 chan->sec_level,
7134 HCI_LE_CONN_TIMEOUT,
7135 HCI_ROLE_SLAVE);
7136 else
7137 hcon = hci_connect_le_scan(hdev, dst, dst_type,
7138 chan->sec_level,
7139 HCI_LE_CONN_TIMEOUT);
7140
7141 } else {
7142 u8 auth_type = l2cap_get_auth_type(chan);
7143 hcon = hci_connect_acl(hdev, dst, chan->sec_level, auth_type);
7144 }
7145
7146 if (IS_ERR(hcon)) {
7147 err = PTR_ERR(hcon);
7148 goto done;
7149 }
7150
7151 conn = l2cap_conn_add(hcon);
7152 if (!conn) {
7153 hci_conn_drop(hcon);
7154 err = -ENOMEM;
7155 goto done;
7156 }
7157
7158 mutex_lock(&conn->chan_lock);
7159 l2cap_chan_lock(chan);
7160
7161 if (cid && __l2cap_get_chan_by_dcid(conn, cid)) {
7162 hci_conn_drop(hcon);
7163 err = -EBUSY;
7164 goto chan_unlock;
7165 }
7166
7167 /* Update source addr of the socket */
7168 bacpy(&chan->src, &hcon->src);
7169 chan->src_type = bdaddr_src_type(hcon);
7170
7171 __l2cap_chan_add(conn, chan);
7172
7173 /* l2cap_chan_add takes its own ref so we can drop this one */
7174 hci_conn_drop(hcon);
7175
7176 l2cap_state_change(chan, BT_CONNECT);
7177 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
7178
7179 /* Release chan->sport so that it can be reused by other
7180 * sockets (as it's only used for listening sockets).
7181 */
7182 write_lock(&chan_list_lock);
7183 chan->sport = 0;
7184 write_unlock(&chan_list_lock);
7185
7186 if (hcon->state == BT_CONNECTED) {
7187 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
7188 __clear_chan_timer(chan);
7189 if (l2cap_chan_check_security(chan, true))
7190 l2cap_state_change(chan, BT_CONNECTED);
7191 } else
7192 l2cap_do_start(chan);
7193 }
7194
7195 err = 0;
7196
7197 chan_unlock:
7198 l2cap_chan_unlock(chan);
7199 mutex_unlock(&conn->chan_lock);
7200 done:
7201 hci_dev_unlock(hdev);
7202 hci_dev_put(hdev);
7203 return err;
7204 }
7205 EXPORT_SYMBOL_GPL(l2cap_chan_connect);
7206
7207 /* ---- L2CAP interface with lower layer (HCI) ---- */
7208
7209 int l2cap_connect_ind(struct hci_dev *hdev, bdaddr_t *bdaddr)
7210 {
7211 int exact = 0, lm1 = 0, lm2 = 0;
7212 struct l2cap_chan *c;
7213
7214 BT_DBG("hdev %s, bdaddr %pMR", hdev->name, bdaddr);
7215
7216 /* Find listening sockets and check their link_mode */
7217 read_lock(&chan_list_lock);
7218 list_for_each_entry(c, &chan_list, global_l) {
7219 if (c->state != BT_LISTEN)
7220 continue;
7221
7222 if (!bacmp(&c->src, &hdev->bdaddr)) {
7223 lm1 |= HCI_LM_ACCEPT;
7224 if (test_bit(FLAG_ROLE_SWITCH, &c->flags))
7225 lm1 |= HCI_LM_MASTER;
7226 exact++;
7227 } else if (!bacmp(&c->src, BDADDR_ANY)) {
7228 lm2 |= HCI_LM_ACCEPT;
7229 if (test_bit(FLAG_ROLE_SWITCH, &c->flags))
7230 lm2 |= HCI_LM_MASTER;
7231 }
7232 }
7233 read_unlock(&chan_list_lock);
7234
7235 return exact ? lm1 : lm2;
7236 }
7237
7238 /* Find the next fixed channel in BT_LISTEN state, continue iteration
7239 * from an existing channel in the list or from the beginning of the
7240 * global list (by passing NULL as first parameter).
7241 */
7242 static struct l2cap_chan *l2cap_global_fixed_chan(struct l2cap_chan *c,
7243 struct hci_conn *hcon)
7244 {
7245 u8 src_type = bdaddr_src_type(hcon);
7246
7247 read_lock(&chan_list_lock);
7248
7249 if (c)
7250 c = list_next_entry(c, global_l);
7251 else
7252 c = list_entry(chan_list.next, typeof(*c), global_l);
7253
7254 list_for_each_entry_from(c, &chan_list, global_l) {
7255 if (c->chan_type != L2CAP_CHAN_FIXED)
7256 continue;
7257 if (c->state != BT_LISTEN)
7258 continue;
7259 if (bacmp(&c->src, &hcon->src) && bacmp(&c->src, BDADDR_ANY))
7260 continue;
7261 if (src_type != c->src_type)
7262 continue;
7263
7264 l2cap_chan_hold(c);
7265 read_unlock(&chan_list_lock);
7266 return c;
7267 }
7268
7269 read_unlock(&chan_list_lock);
7270
7271 return NULL;
7272 }
7273
7274 static void l2cap_connect_cfm(struct hci_conn *hcon, u8 status)
7275 {
7276 struct hci_dev *hdev = hcon->hdev;
7277 struct l2cap_conn *conn;
7278 struct l2cap_chan *pchan;
7279 u8 dst_type;
7280
7281 if (hcon->type != ACL_LINK && hcon->type != LE_LINK)
7282 return;
7283
7284 BT_DBG("hcon %p bdaddr %pMR status %d", hcon, &hcon->dst, status);
7285
7286 if (status) {
7287 l2cap_conn_del(hcon, bt_to_errno(status));
7288 return;
7289 }
7290
7291 conn = l2cap_conn_add(hcon);
7292 if (!conn)
7293 return;
7294
7295 dst_type = bdaddr_dst_type(hcon);
7296
7297 /* If device is blocked, do not create channels for it */
7298 if (hci_bdaddr_list_lookup(&hdev->blacklist, &hcon->dst, dst_type))
7299 return;
7300
7301 /* Find fixed channels and notify them of the new connection. We
7302 * use multiple individual lookups, continuing each time where
7303 * we left off, because the list lock would prevent calling the
7304 * potentially sleeping l2cap_chan_lock() function.
7305 */
7306 pchan = l2cap_global_fixed_chan(NULL, hcon);
7307 while (pchan) {
7308 struct l2cap_chan *chan, *next;
7309
7310 /* Client fixed channels should override server ones */
7311 if (__l2cap_get_chan_by_dcid(conn, pchan->scid))
7312 goto next;
7313
7314 l2cap_chan_lock(pchan);
7315 chan = pchan->ops->new_connection(pchan);
7316 if (chan) {
7317 bacpy(&chan->src, &hcon->src);
7318 bacpy(&chan->dst, &hcon->dst);
7319 chan->src_type = bdaddr_src_type(hcon);
7320 chan->dst_type = dst_type;
7321
7322 __l2cap_chan_add(conn, chan);
7323 }
7324
7325 l2cap_chan_unlock(pchan);
7326 next:
7327 next = l2cap_global_fixed_chan(pchan, hcon);
7328 l2cap_chan_put(pchan);
7329 pchan = next;
7330 }
7331
7332 l2cap_conn_ready(conn);
7333 }
7334
7335 int l2cap_disconn_ind(struct hci_conn *hcon)
7336 {
7337 struct l2cap_conn *conn = hcon->l2cap_data;
7338
7339 BT_DBG("hcon %p", hcon);
7340
7341 if (!conn)
7342 return HCI_ERROR_REMOTE_USER_TERM;
7343 return conn->disc_reason;
7344 }
7345
7346 static void l2cap_disconn_cfm(struct hci_conn *hcon, u8 reason)
7347 {
7348 if (hcon->type != ACL_LINK && hcon->type != LE_LINK)
7349 return;
7350
7351 BT_DBG("hcon %p reason %d", hcon, reason);
7352
7353 l2cap_conn_del(hcon, bt_to_errno(reason));
7354 }
7355
7356 static inline void l2cap_check_encryption(struct l2cap_chan *chan, u8 encrypt)
7357 {
7358 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED)
7359 return;
7360
7361 if (encrypt == 0x00) {
7362 if (chan->sec_level == BT_SECURITY_MEDIUM) {
7363 __set_chan_timer(chan, L2CAP_ENC_TIMEOUT);
7364 } else if (chan->sec_level == BT_SECURITY_HIGH ||
7365 chan->sec_level == BT_SECURITY_FIPS)
7366 l2cap_chan_close(chan, ECONNREFUSED);
7367 } else {
7368 if (chan->sec_level == BT_SECURITY_MEDIUM)
7369 __clear_chan_timer(chan);
7370 }
7371 }
7372
7373 static void l2cap_security_cfm(struct hci_conn *hcon, u8 status, u8 encrypt)
7374 {
7375 struct l2cap_conn *conn = hcon->l2cap_data;
7376 struct l2cap_chan *chan;
7377
7378 if (!conn)
7379 return;
7380
7381 BT_DBG("conn %p status 0x%2.2x encrypt %u", conn, status, encrypt);
7382
7383 mutex_lock(&conn->chan_lock);
7384
7385 list_for_each_entry(chan, &conn->chan_l, list) {
7386 l2cap_chan_lock(chan);
7387
7388 BT_DBG("chan %p scid 0x%4.4x state %s", chan, chan->scid,
7389 state_to_string(chan->state));
7390
7391 if (chan->scid == L2CAP_CID_A2MP) {
7392 l2cap_chan_unlock(chan);
7393 continue;
7394 }
7395
7396 if (!status && encrypt)
7397 chan->sec_level = hcon->sec_level;
7398
7399 if (!__l2cap_no_conn_pending(chan)) {
7400 l2cap_chan_unlock(chan);
7401 continue;
7402 }
7403
7404 if (!status && (chan->state == BT_CONNECTED ||
7405 chan->state == BT_CONFIG)) {
7406 chan->ops->resume(chan);
7407 l2cap_check_encryption(chan, encrypt);
7408 l2cap_chan_unlock(chan);
7409 continue;
7410 }
7411
7412 if (chan->state == BT_CONNECT) {
7413 if (!status)
7414 l2cap_start_connection(chan);
7415 else
7416 __set_chan_timer(chan, L2CAP_DISC_TIMEOUT);
7417 } else if (chan->state == BT_CONNECT2 &&
7418 chan->mode != L2CAP_MODE_LE_FLOWCTL) {
7419 struct l2cap_conn_rsp rsp;
7420 __u16 res, stat;
7421
7422 if (!status) {
7423 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
7424 res = L2CAP_CR_PEND;
7425 stat = L2CAP_CS_AUTHOR_PEND;
7426 chan->ops->defer(chan);
7427 } else {
7428 l2cap_state_change(chan, BT_CONFIG);
7429 res = L2CAP_CR_SUCCESS;
7430 stat = L2CAP_CS_NO_INFO;
7431 }
7432 } else {
7433 l2cap_state_change(chan, BT_DISCONN);
7434 __set_chan_timer(chan, L2CAP_DISC_TIMEOUT);
7435 res = L2CAP_CR_SEC_BLOCK;
7436 stat = L2CAP_CS_NO_INFO;
7437 }
7438
7439 rsp.scid = cpu_to_le16(chan->dcid);
7440 rsp.dcid = cpu_to_le16(chan->scid);
7441 rsp.result = cpu_to_le16(res);
7442 rsp.status = cpu_to_le16(stat);
7443 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP,
7444 sizeof(rsp), &rsp);
7445
7446 if (!test_bit(CONF_REQ_SENT, &chan->conf_state) &&
7447 res == L2CAP_CR_SUCCESS) {
7448 char buf[128];
7449 set_bit(CONF_REQ_SENT, &chan->conf_state);
7450 l2cap_send_cmd(conn, l2cap_get_ident(conn),
7451 L2CAP_CONF_REQ,
7452 l2cap_build_conf_req(chan, buf),
7453 buf);
7454 chan->num_conf_req++;
7455 }
7456 }
7457
7458 l2cap_chan_unlock(chan);
7459 }
7460
7461 mutex_unlock(&conn->chan_lock);
7462 }
7463
7464 void l2cap_recv_acldata(struct hci_conn *hcon, struct sk_buff *skb, u16 flags)
7465 {
7466 struct l2cap_conn *conn = hcon->l2cap_data;
7467 struct l2cap_hdr *hdr;
7468 int len;
7469
7470 /* For AMP controller do not create l2cap conn */
7471 if (!conn && hcon->hdev->dev_type != HCI_PRIMARY)
7472 goto drop;
7473
7474 if (!conn)
7475 conn = l2cap_conn_add(hcon);
7476
7477 if (!conn)
7478 goto drop;
7479
7480 BT_DBG("conn %p len %d flags 0x%x", conn, skb->len, flags);
7481
7482 switch (flags) {
7483 case ACL_START:
7484 case ACL_START_NO_FLUSH:
7485 case ACL_COMPLETE:
7486 if (conn->rx_len) {
7487 BT_ERR("Unexpected start frame (len %d)", skb->len);
7488 kfree_skb(conn->rx_skb);
7489 conn->rx_skb = NULL;
7490 conn->rx_len = 0;
7491 l2cap_conn_unreliable(conn, ECOMM);
7492 }
7493
7494 /* Start fragment always begin with Basic L2CAP header */
7495 if (skb->len < L2CAP_HDR_SIZE) {
7496 BT_ERR("Frame is too short (len %d)", skb->len);
7497 l2cap_conn_unreliable(conn, ECOMM);
7498 goto drop;
7499 }
7500
7501 hdr = (struct l2cap_hdr *) skb->data;
7502 len = __le16_to_cpu(hdr->len) + L2CAP_HDR_SIZE;
7503
7504 if (len == skb->len) {
7505 /* Complete frame received */
7506 l2cap_recv_frame(conn, skb);
7507 return;
7508 }
7509
7510 BT_DBG("Start: total len %d, frag len %d", len, skb->len);
7511
7512 if (skb->len > len) {
7513 BT_ERR("Frame is too long (len %d, expected len %d)",
7514 skb->len, len);
7515 l2cap_conn_unreliable(conn, ECOMM);
7516 goto drop;
7517 }
7518
7519 /* Allocate skb for the complete frame (with header) */
7520 conn->rx_skb = bt_skb_alloc(len, GFP_KERNEL);
7521 if (!conn->rx_skb)
7522 goto drop;
7523
7524 skb_copy_from_linear_data(skb, skb_put(conn->rx_skb, skb->len),
7525 skb->len);
7526 conn->rx_len = len - skb->len;
7527 break;
7528
7529 case ACL_CONT:
7530 BT_DBG("Cont: frag len %d (expecting %d)", skb->len, conn->rx_len);
7531
7532 if (!conn->rx_len) {
7533 BT_ERR("Unexpected continuation frame (len %d)", skb->len);
7534 l2cap_conn_unreliable(conn, ECOMM);
7535 goto drop;
7536 }
7537
7538 if (skb->len > conn->rx_len) {
7539 BT_ERR("Fragment is too long (len %d, expected %d)",
7540 skb->len, conn->rx_len);
7541 kfree_skb(conn->rx_skb);
7542 conn->rx_skb = NULL;
7543 conn->rx_len = 0;
7544 l2cap_conn_unreliable(conn, ECOMM);
7545 goto drop;
7546 }
7547
7548 skb_copy_from_linear_data(skb, skb_put(conn->rx_skb, skb->len),
7549 skb->len);
7550 conn->rx_len -= skb->len;
7551
7552 if (!conn->rx_len) {
7553 /* Complete frame received. l2cap_recv_frame
7554 * takes ownership of the skb so set the global
7555 * rx_skb pointer to NULL first.
7556 */
7557 struct sk_buff *rx_skb = conn->rx_skb;
7558 conn->rx_skb = NULL;
7559 l2cap_recv_frame(conn, rx_skb);
7560 }
7561 break;
7562 }
7563
7564 drop:
7565 kfree_skb(skb);
7566 }
7567
7568 static struct hci_cb l2cap_cb = {
7569 .name = "L2CAP",
7570 .connect_cfm = l2cap_connect_cfm,
7571 .disconn_cfm = l2cap_disconn_cfm,
7572 .security_cfm = l2cap_security_cfm,
7573 };
7574
7575 static int l2cap_debugfs_show(struct seq_file *f, void *p)
7576 {
7577 struct l2cap_chan *c;
7578
7579 read_lock(&chan_list_lock);
7580
7581 list_for_each_entry(c, &chan_list, global_l) {
7582 seq_printf(f, "%pMR (%u) %pMR (%u) %d %d 0x%4.4x 0x%4.4x %d %d %d %d\n",
7583 &c->src, c->src_type, &c->dst, c->dst_type,
7584 c->state, __le16_to_cpu(c->psm),
7585 c->scid, c->dcid, c->imtu, c->omtu,
7586 c->sec_level, c->mode);
7587 }
7588
7589 read_unlock(&chan_list_lock);
7590
7591 return 0;
7592 }
7593
7594 static int l2cap_debugfs_open(struct inode *inode, struct file *file)
7595 {
7596 return single_open(file, l2cap_debugfs_show, inode->i_private);
7597 }
7598
7599 static const struct file_operations l2cap_debugfs_fops = {
7600 .open = l2cap_debugfs_open,
7601 .read = seq_read,
7602 .llseek = seq_lseek,
7603 .release = single_release,
7604 };
7605
7606 static struct dentry *l2cap_debugfs;
7607
7608 int __init l2cap_init(void)
7609 {
7610 int err;
7611
7612 err = l2cap_init_sockets();
7613 if (err < 0)
7614 return err;
7615
7616 hci_register_cb(&l2cap_cb);
7617
7618 if (IS_ERR_OR_NULL(bt_debugfs))
7619 return 0;
7620
7621 l2cap_debugfs = debugfs_create_file("l2cap", 0444, bt_debugfs,
7622 NULL, &l2cap_debugfs_fops);
7623
7624 debugfs_create_u16("l2cap_le_max_credits", 0644, bt_debugfs,
7625 &le_max_credits);
7626 debugfs_create_u16("l2cap_le_default_mps", 0644, bt_debugfs,
7627 &le_default_mps);
7628
7629 return 0;
7630 }
7631
7632 void l2cap_exit(void)
7633 {
7634 debugfs_remove(l2cap_debugfs);
7635 hci_unregister_cb(&l2cap_cb);
7636 l2cap_cleanup_sockets();
7637 }
7638
7639 module_param(disable_ertm, bool, 0644);
7640 MODULE_PARM_DESC(disable_ertm, "Disable enhanced retransmission mode");
Linux kernel - Deliverables
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