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1/*
2 BlueZ - Bluetooth protocol stack for Linux
3 Copyright (C) 2000-2001 Qualcomm Incorporated
4 Copyright (C) 2009-2010 Gustavo F. Padovan <gustavo@padovan.org>
5 Copyright (C) 2010 Google Inc.
6 Copyright (C) 2011 ProFUSION Embedded Systems
7 Copyright (c) 2012 Code Aurora Forum. All rights reserved.
8
9 Written 2000,2001 by Maxim Krasnyansky <maxk@qualcomm.com>
10
11 This program is free software; you can redistribute it and/or modify
12 it under the terms of the GNU General Public License version 2 as
13 published by the Free Software Foundation;
14
15 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
16 OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS.
18 IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) AND AUTHOR(S) BE LIABLE FOR ANY
19 CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES
20 WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
21 ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
22 OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
23
24 ALL LIABILITY, INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PATENTS,
25 COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS, RELATING TO USE OF THIS
26 SOFTWARE IS DISCLAIMED.
27*/
28
29/* Bluetooth L2CAP core. */
30
31#include <linux/module.h>
32
33#include <linux/debugfs.h>
34#include <linux/crc16.h>
35#include <linux/filter.h>
36
37#include <net/bluetooth/bluetooth.h>
38#include <net/bluetooth/hci_core.h>
39#include <net/bluetooth/l2cap.h>
40
41#include "smp.h"
42#include "a2mp.h"
43#include "amp.h"
44
45#define LE_FLOWCTL_MAX_CREDITS 65535
46
47bool disable_ertm;
48
49static u32 l2cap_feat_mask = L2CAP_FEAT_FIXED_CHAN | L2CAP_FEAT_UCD;
50
51static LIST_HEAD(chan_list);
52static DEFINE_RWLOCK(chan_list_lock);
53
54static struct sk_buff *l2cap_build_cmd(struct l2cap_conn *conn,
55 u8 code, u8 ident, u16 dlen, void *data);
56static void l2cap_send_cmd(struct l2cap_conn *conn, u8 ident, u8 code, u16 len,
57 void *data);
58static int l2cap_build_conf_req(struct l2cap_chan *chan, void *data, size_t data_size);
59static void l2cap_send_disconn_req(struct l2cap_chan *chan, int err);
60
61static void l2cap_tx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
62 struct sk_buff_head *skbs, u8 event);
63
64static inline u8 bdaddr_type(u8 link_type, u8 bdaddr_type)
65{
66 if (link_type == LE_LINK) {
67 if (bdaddr_type == ADDR_LE_DEV_PUBLIC)
68 return BDADDR_LE_PUBLIC;
69 else
70 return BDADDR_LE_RANDOM;
71 }
72
73 return BDADDR_BREDR;
74}
75
76static inline u8 bdaddr_src_type(struct hci_conn *hcon)
77{
78 return bdaddr_type(hcon->type, hcon->src_type);
79}
80
81static inline u8 bdaddr_dst_type(struct hci_conn *hcon)
82{
83 return bdaddr_type(hcon->type, hcon->dst_type);
84}
85
86/* ---- L2CAP channels ---- */
87
88static struct l2cap_chan *__l2cap_get_chan_by_dcid(struct l2cap_conn *conn,
89 u16 cid)
90{
91 struct l2cap_chan *c;
92
93 list_for_each_entry(c, &conn->chan_l, list) {
94 if (c->dcid == cid)
95 return c;
96 }
97 return NULL;
98}
99
100static struct l2cap_chan *__l2cap_get_chan_by_scid(struct l2cap_conn *conn,
101 u16 cid)
102{
103 struct l2cap_chan *c;
104
105 list_for_each_entry(c, &conn->chan_l, list) {
106 if (c->scid == cid)
107 return c;
108 }
109 return NULL;
110}
111
112/* Find channel with given SCID.
113 * Returns locked channel. */
114static struct l2cap_chan *l2cap_get_chan_by_scid(struct l2cap_conn *conn,
115 u16 cid)
116{
117 struct l2cap_chan *c;
118
119 mutex_lock(&conn->chan_lock);
120 c = __l2cap_get_chan_by_scid(conn, cid);
121 if (c)
122 l2cap_chan_lock(c);
123 mutex_unlock(&conn->chan_lock);
124
125 return c;
126}
127
128/* Find channel with given DCID.
129 * Returns locked channel.
130 */
131static struct l2cap_chan *l2cap_get_chan_by_dcid(struct l2cap_conn *conn,
132 u16 cid)
133{
134 struct l2cap_chan *c;
135
136 mutex_lock(&conn->chan_lock);
137 c = __l2cap_get_chan_by_dcid(conn, cid);
138 if (c)
139 l2cap_chan_lock(c);
140 mutex_unlock(&conn->chan_lock);
141
142 return c;
143}
144
145static struct l2cap_chan *__l2cap_get_chan_by_ident(struct l2cap_conn *conn,
146 u8 ident)
147{
148 struct l2cap_chan *c;
149
150 list_for_each_entry(c, &conn->chan_l, list) {
151 if (c->ident == ident)
152 return c;
153 }
154 return NULL;
155}
156
157static struct l2cap_chan *l2cap_get_chan_by_ident(struct l2cap_conn *conn,
158 u8 ident)
159{
160 struct l2cap_chan *c;
161
162 mutex_lock(&conn->chan_lock);
163 c = __l2cap_get_chan_by_ident(conn, ident);
164 if (c)
165 l2cap_chan_lock(c);
166 mutex_unlock(&conn->chan_lock);
167
168 return c;
169}
170
171static struct l2cap_chan *__l2cap_global_chan_by_addr(__le16 psm, bdaddr_t *src,
172 u8 src_type)
173{
174 struct l2cap_chan *c;
175
176 list_for_each_entry(c, &chan_list, global_l) {
177 if (src_type == BDADDR_BREDR && c->src_type != BDADDR_BREDR)
178 continue;
179
180 if (src_type != BDADDR_BREDR && c->src_type == BDADDR_BREDR)
181 continue;
182
183 if (c->sport == psm && !bacmp(&c->src, src))
184 return c;
185 }
186 return NULL;
187}
188
189int l2cap_add_psm(struct l2cap_chan *chan, bdaddr_t *src, __le16 psm)
190{
191 int err;
192
193 write_lock(&chan_list_lock);
194
195 if (psm && __l2cap_global_chan_by_addr(psm, src, chan->src_type)) {
196 err = -EADDRINUSE;
197 goto done;
198 }
199
200 if (psm) {
201 chan->psm = psm;
202 chan->sport = psm;
203 err = 0;
204 } else {
205 u16 p, start, end, incr;
206
207 if (chan->src_type == BDADDR_BREDR) {
208 start = L2CAP_PSM_DYN_START;
209 end = L2CAP_PSM_AUTO_END;
210 incr = 2;
211 } else {
212 start = L2CAP_PSM_LE_DYN_START;
213 end = L2CAP_PSM_LE_DYN_END;
214 incr = 1;
215 }
216
217 err = -EINVAL;
218 for (p = start; p <= end; p += incr)
219 if (!__l2cap_global_chan_by_addr(cpu_to_le16(p), src,
220 chan->src_type)) {
221 chan->psm = cpu_to_le16(p);
222 chan->sport = cpu_to_le16(p);
223 err = 0;
224 break;
225 }
226 }
227
228done:
229 write_unlock(&chan_list_lock);
230 return err;
231}
232EXPORT_SYMBOL_GPL(l2cap_add_psm);
233
234int l2cap_add_scid(struct l2cap_chan *chan, __u16 scid)
235{
236 write_lock(&chan_list_lock);
237
238 /* Override the defaults (which are for conn-oriented) */
239 chan->omtu = L2CAP_DEFAULT_MTU;
240 chan->chan_type = L2CAP_CHAN_FIXED;
241
242 chan->scid = scid;
243
244 write_unlock(&chan_list_lock);
245
246 return 0;
247}
248
249static u16 l2cap_alloc_cid(struct l2cap_conn *conn)
250{
251 u16 cid, dyn_end;
252
253 if (conn->hcon->type == LE_LINK)
254 dyn_end = L2CAP_CID_LE_DYN_END;
255 else
256 dyn_end = L2CAP_CID_DYN_END;
257
258 for (cid = L2CAP_CID_DYN_START; cid <= dyn_end; cid++) {
259 if (!__l2cap_get_chan_by_scid(conn, cid))
260 return cid;
261 }
262
263 return 0;
264}
265
266static void l2cap_state_change(struct l2cap_chan *chan, int state)
267{
268 BT_DBG("chan %p %s -> %s", chan, state_to_string(chan->state),
269 state_to_string(state));
270
271 chan->state = state;
272 chan->ops->state_change(chan, state, 0);
273}
274
275static inline void l2cap_state_change_and_error(struct l2cap_chan *chan,
276 int state, int err)
277{
278 chan->state = state;
279 chan->ops->state_change(chan, chan->state, err);
280}
281
282static inline void l2cap_chan_set_err(struct l2cap_chan *chan, int err)
283{
284 chan->ops->state_change(chan, chan->state, err);
285}
286
287static void __set_retrans_timer(struct l2cap_chan *chan)
288{
289 if (!delayed_work_pending(&chan->monitor_timer) &&
290 chan->retrans_timeout) {
291 l2cap_set_timer(chan, &chan->retrans_timer,
292 msecs_to_jiffies(chan->retrans_timeout));
293 }
294}
295
296static void __set_monitor_timer(struct l2cap_chan *chan)
297{
298 __clear_retrans_timer(chan);
299 if (chan->monitor_timeout) {
300 l2cap_set_timer(chan, &chan->monitor_timer,
301 msecs_to_jiffies(chan->monitor_timeout));
302 }
303}
304
305static struct sk_buff *l2cap_ertm_seq_in_queue(struct sk_buff_head *head,
306 u16 seq)
307{
308 struct sk_buff *skb;
309
310 skb_queue_walk(head, skb) {
311 if (bt_cb(skb)->l2cap.txseq == seq)
312 return skb;
313 }
314
315 return NULL;
316}
317
318/* ---- L2CAP sequence number lists ---- */
319
320/* For ERTM, ordered lists of sequence numbers must be tracked for
321 * SREJ requests that are received and for frames that are to be
322 * retransmitted. These seq_list functions implement a singly-linked
323 * list in an array, where membership in the list can also be checked
324 * in constant time. Items can also be added to the tail of the list
325 * and removed from the head in constant time, without further memory
326 * allocs or frees.
327 */
328
329static int l2cap_seq_list_init(struct l2cap_seq_list *seq_list, u16 size)
330{
331 size_t alloc_size, i;
332
333 /* Allocated size is a power of 2 to map sequence numbers
334 * (which may be up to 14 bits) in to a smaller array that is
335 * sized for the negotiated ERTM transmit windows.
336 */
337 alloc_size = roundup_pow_of_two(size);
338
339 seq_list->list = kmalloc_array(alloc_size, sizeof(u16), GFP_KERNEL);
340 if (!seq_list->list)
341 return -ENOMEM;
342
343 seq_list->mask = alloc_size - 1;
344 seq_list->head = L2CAP_SEQ_LIST_CLEAR;
345 seq_list->tail = L2CAP_SEQ_LIST_CLEAR;
346 for (i = 0; i < alloc_size; i++)
347 seq_list->list[i] = L2CAP_SEQ_LIST_CLEAR;
348
349 return 0;
350}
351
352static inline void l2cap_seq_list_free(struct l2cap_seq_list *seq_list)
353{
354 kfree(seq_list->list);
355}
356
357static inline bool l2cap_seq_list_contains(struct l2cap_seq_list *seq_list,
358 u16 seq)
359{
360 /* Constant-time check for list membership */
361 return seq_list->list[seq & seq_list->mask] != L2CAP_SEQ_LIST_CLEAR;
362}
363
364static inline u16 l2cap_seq_list_pop(struct l2cap_seq_list *seq_list)
365{
366 u16 seq = seq_list->head;
367 u16 mask = seq_list->mask;
368
369 seq_list->head = seq_list->list[seq & mask];
370 seq_list->list[seq & mask] = L2CAP_SEQ_LIST_CLEAR;
371
372 if (seq_list->head == L2CAP_SEQ_LIST_TAIL) {
373 seq_list->head = L2CAP_SEQ_LIST_CLEAR;
374 seq_list->tail = L2CAP_SEQ_LIST_CLEAR;
375 }
376
377 return seq;
378}
379
380static void l2cap_seq_list_clear(struct l2cap_seq_list *seq_list)
381{
382 u16 i;
383
384 if (seq_list->head == L2CAP_SEQ_LIST_CLEAR)
385 return;
386
387 for (i = 0; i <= seq_list->mask; i++)
388 seq_list->list[i] = L2CAP_SEQ_LIST_CLEAR;
389
390 seq_list->head = L2CAP_SEQ_LIST_CLEAR;
391 seq_list->tail = L2CAP_SEQ_LIST_CLEAR;
392}
393
394static void l2cap_seq_list_append(struct l2cap_seq_list *seq_list, u16 seq)
395{
396 u16 mask = seq_list->mask;
397
398 /* All appends happen in constant time */
399
400 if (seq_list->list[seq & mask] != L2CAP_SEQ_LIST_CLEAR)
401 return;
402
403 if (seq_list->tail == L2CAP_SEQ_LIST_CLEAR)
404 seq_list->head = seq;
405 else
406 seq_list->list[seq_list->tail & mask] = seq;
407
408 seq_list->tail = seq;
409 seq_list->list[seq & mask] = L2CAP_SEQ_LIST_TAIL;
410}
411
412static void l2cap_chan_timeout(struct work_struct *work)
413{
414 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
415 chan_timer.work);
416 struct l2cap_conn *conn = chan->conn;
417 int reason;
418
419 BT_DBG("chan %p state %s", chan, state_to_string(chan->state));
420
421 mutex_lock(&conn->chan_lock);
422 l2cap_chan_lock(chan);
423
424 if (chan->state == BT_CONNECTED || chan->state == BT_CONFIG)
425 reason = ECONNREFUSED;
426 else if (chan->state == BT_CONNECT &&
427 chan->sec_level != BT_SECURITY_SDP)
428 reason = ECONNREFUSED;
429 else
430 reason = ETIMEDOUT;
431
432 l2cap_chan_close(chan, reason);
433
434 l2cap_chan_unlock(chan);
435
436 chan->ops->close(chan);
437 mutex_unlock(&conn->chan_lock);
438
439 l2cap_chan_put(chan);
440}
441
442struct l2cap_chan *l2cap_chan_create(void)
443{
444 struct l2cap_chan *chan;
445
446 chan = kzalloc(sizeof(*chan), GFP_ATOMIC);
447 if (!chan)
448 return NULL;
449
450 mutex_init(&chan->lock);
451
452 /* Set default lock nesting level */
453 atomic_set(&chan->nesting, L2CAP_NESTING_NORMAL);
454
455 write_lock(&chan_list_lock);
456 list_add(&chan->global_l, &chan_list);
457 write_unlock(&chan_list_lock);
458
459 INIT_DELAYED_WORK(&chan->chan_timer, l2cap_chan_timeout);
460
461 chan->state = BT_OPEN;
462
463 kref_init(&chan->kref);
464
465 /* This flag is cleared in l2cap_chan_ready() */
466 set_bit(CONF_NOT_COMPLETE, &chan->conf_state);
467
468 BT_DBG("chan %p", chan);
469
470 return chan;
471}
472EXPORT_SYMBOL_GPL(l2cap_chan_create);
473
474static void l2cap_chan_destroy(struct kref *kref)
475{
476 struct l2cap_chan *chan = container_of(kref, struct l2cap_chan, kref);
477
478 BT_DBG("chan %p", chan);
479
480 write_lock(&chan_list_lock);
481 list_del(&chan->global_l);
482 write_unlock(&chan_list_lock);
483
484 kfree(chan);
485}
486
487void l2cap_chan_hold(struct l2cap_chan *c)
488{
489 BT_DBG("chan %p orig refcnt %d", c, kref_read(&c->kref));
490
491 kref_get(&c->kref);
492}
493
494void l2cap_chan_put(struct l2cap_chan *c)
495{
496 BT_DBG("chan %p orig refcnt %d", c, kref_read(&c->kref));
497
498 kref_put(&c->kref, l2cap_chan_destroy);
499}
500EXPORT_SYMBOL_GPL(l2cap_chan_put);
501
502void l2cap_chan_set_defaults(struct l2cap_chan *chan)
503{
504 chan->fcs = L2CAP_FCS_CRC16;
505 chan->max_tx = L2CAP_DEFAULT_MAX_TX;
506 chan->tx_win = L2CAP_DEFAULT_TX_WINDOW;
507 chan->tx_win_max = L2CAP_DEFAULT_TX_WINDOW;
508 chan->remote_max_tx = chan->max_tx;
509 chan->remote_tx_win = chan->tx_win;
510 chan->ack_win = L2CAP_DEFAULT_TX_WINDOW;
511 chan->sec_level = BT_SECURITY_LOW;
512 chan->flush_to = L2CAP_DEFAULT_FLUSH_TO;
513 chan->retrans_timeout = L2CAP_DEFAULT_RETRANS_TO;
514 chan->monitor_timeout = L2CAP_DEFAULT_MONITOR_TO;
515 chan->conf_state = 0;
516
517 set_bit(FLAG_FORCE_ACTIVE, &chan->flags);
518}
519EXPORT_SYMBOL_GPL(l2cap_chan_set_defaults);
520
521static void l2cap_le_flowctl_init(struct l2cap_chan *chan, u16 tx_credits)
522{
523 chan->sdu = NULL;
524 chan->sdu_last_frag = NULL;
525 chan->sdu_len = 0;
526 chan->tx_credits = tx_credits;
527 /* Derive MPS from connection MTU to stop HCI fragmentation */
528 chan->mps = min_t(u16, chan->imtu, chan->conn->mtu - L2CAP_HDR_SIZE);
529 /* Give enough credits for a full packet */
530 chan->rx_credits = (chan->imtu / chan->mps) + 1;
531
532 skb_queue_head_init(&chan->tx_q);
533}
534
535void __l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan)
536{
537 BT_DBG("conn %p, psm 0x%2.2x, dcid 0x%4.4x", conn,
538 __le16_to_cpu(chan->psm), chan->dcid);
539
540 conn->disc_reason = HCI_ERROR_REMOTE_USER_TERM;
541
542 chan->conn = conn;
543
544 switch (chan->chan_type) {
545 case L2CAP_CHAN_CONN_ORIENTED:
546 /* Alloc CID for connection-oriented socket */
547 chan->scid = l2cap_alloc_cid(conn);
548 if (conn->hcon->type == ACL_LINK)
549 chan->omtu = L2CAP_DEFAULT_MTU;
550 break;
551
552 case L2CAP_CHAN_CONN_LESS:
553 /* Connectionless socket */
554 chan->scid = L2CAP_CID_CONN_LESS;
555 chan->dcid = L2CAP_CID_CONN_LESS;
556 chan->omtu = L2CAP_DEFAULT_MTU;
557 break;
558
559 case L2CAP_CHAN_FIXED:
560 /* Caller will set CID and CID specific MTU values */
561 break;
562
563 default:
564 /* Raw socket can send/recv signalling messages only */
565 chan->scid = L2CAP_CID_SIGNALING;
566 chan->dcid = L2CAP_CID_SIGNALING;
567 chan->omtu = L2CAP_DEFAULT_MTU;
568 }
569
570 chan->local_id = L2CAP_BESTEFFORT_ID;
571 chan->local_stype = L2CAP_SERV_BESTEFFORT;
572 chan->local_msdu = L2CAP_DEFAULT_MAX_SDU_SIZE;
573 chan->local_sdu_itime = L2CAP_DEFAULT_SDU_ITIME;
574 chan->local_acc_lat = L2CAP_DEFAULT_ACC_LAT;
575 chan->local_flush_to = L2CAP_EFS_DEFAULT_FLUSH_TO;
576
577 l2cap_chan_hold(chan);
578
579 /* Only keep a reference for fixed channels if they requested it */
580 if (chan->chan_type != L2CAP_CHAN_FIXED ||
581 test_bit(FLAG_HOLD_HCI_CONN, &chan->flags))
582 hci_conn_hold(conn->hcon);
583
584 list_add(&chan->list, &conn->chan_l);
585}
586
587void l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan)
588{
589 mutex_lock(&conn->chan_lock);
590 __l2cap_chan_add(conn, chan);
591 mutex_unlock(&conn->chan_lock);
592}
593
594void l2cap_chan_del(struct l2cap_chan *chan, int err)
595{
596 struct l2cap_conn *conn = chan->conn;
597
598 __clear_chan_timer(chan);
599
600 BT_DBG("chan %p, conn %p, err %d, state %s", chan, conn, err,
601 state_to_string(chan->state));
602
603 chan->ops->teardown(chan, err);
604
605 if (conn) {
606 struct amp_mgr *mgr = conn->hcon->amp_mgr;
607 /* Delete from channel list */
608 list_del(&chan->list);
609
610 l2cap_chan_put(chan);
611
612 chan->conn = NULL;
613
614 /* Reference was only held for non-fixed channels or
615 * fixed channels that explicitly requested it using the
616 * FLAG_HOLD_HCI_CONN flag.
617 */
618 if (chan->chan_type != L2CAP_CHAN_FIXED ||
619 test_bit(FLAG_HOLD_HCI_CONN, &chan->flags))
620 hci_conn_drop(conn->hcon);
621
622 if (mgr && mgr->bredr_chan == chan)
623 mgr->bredr_chan = NULL;
624 }
625
626 if (chan->hs_hchan) {
627 struct hci_chan *hs_hchan = chan->hs_hchan;
628
629 BT_DBG("chan %p disconnect hs_hchan %p", chan, hs_hchan);
630 amp_disconnect_logical_link(hs_hchan);
631 }
632
633 if (test_bit(CONF_NOT_COMPLETE, &chan->conf_state))
634 return;
635
636 switch(chan->mode) {
637 case L2CAP_MODE_BASIC:
638 break;
639
640 case L2CAP_MODE_LE_FLOWCTL:
641 skb_queue_purge(&chan->tx_q);
642 break;
643
644 case L2CAP_MODE_ERTM:
645 __clear_retrans_timer(chan);
646 __clear_monitor_timer(chan);
647 __clear_ack_timer(chan);
648
649 skb_queue_purge(&chan->srej_q);
650
651 l2cap_seq_list_free(&chan->srej_list);
652 l2cap_seq_list_free(&chan->retrans_list);
653
654 /* fall through */
655
656 case L2CAP_MODE_STREAMING:
657 skb_queue_purge(&chan->tx_q);
658 break;
659 }
660
661 return;
662}
663EXPORT_SYMBOL_GPL(l2cap_chan_del);
664
665static void l2cap_conn_update_id_addr(struct work_struct *work)
666{
667 struct l2cap_conn *conn = container_of(work, struct l2cap_conn,
668 id_addr_update_work);
669 struct hci_conn *hcon = conn->hcon;
670 struct l2cap_chan *chan;
671
672 mutex_lock(&conn->chan_lock);
673
674 list_for_each_entry(chan, &conn->chan_l, list) {
675 l2cap_chan_lock(chan);
676 bacpy(&chan->dst, &hcon->dst);
677 chan->dst_type = bdaddr_dst_type(hcon);
678 l2cap_chan_unlock(chan);
679 }
680
681 mutex_unlock(&conn->chan_lock);
682}
683
684static void l2cap_chan_le_connect_reject(struct l2cap_chan *chan)
685{
686 struct l2cap_conn *conn = chan->conn;
687 struct l2cap_le_conn_rsp rsp;
688 u16 result;
689
690 if (test_bit(FLAG_DEFER_SETUP, &chan->flags))
691 result = L2CAP_CR_LE_AUTHORIZATION;
692 else
693 result = L2CAP_CR_LE_BAD_PSM;
694
695 l2cap_state_change(chan, BT_DISCONN);
696
697 rsp.dcid = cpu_to_le16(chan->scid);
698 rsp.mtu = cpu_to_le16(chan->imtu);
699 rsp.mps = cpu_to_le16(chan->mps);
700 rsp.credits = cpu_to_le16(chan->rx_credits);
701 rsp.result = cpu_to_le16(result);
702
703 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CONN_RSP, sizeof(rsp),
704 &rsp);
705}
706
707static void l2cap_chan_connect_reject(struct l2cap_chan *chan)
708{
709 struct l2cap_conn *conn = chan->conn;
710 struct l2cap_conn_rsp rsp;
711 u16 result;
712
713 if (test_bit(FLAG_DEFER_SETUP, &chan->flags))
714 result = L2CAP_CR_SEC_BLOCK;
715 else
716 result = L2CAP_CR_BAD_PSM;
717
718 l2cap_state_change(chan, BT_DISCONN);
719
720 rsp.scid = cpu_to_le16(chan->dcid);
721 rsp.dcid = cpu_to_le16(chan->scid);
722 rsp.result = cpu_to_le16(result);
723 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
724
725 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP, sizeof(rsp), &rsp);
726}
727
728void l2cap_chan_close(struct l2cap_chan *chan, int reason)
729{
730 struct l2cap_conn *conn = chan->conn;
731
732 BT_DBG("chan %p state %s", chan, state_to_string(chan->state));
733
734 switch (chan->state) {
735 case BT_LISTEN:
736 chan->ops->teardown(chan, 0);
737 break;
738
739 case BT_CONNECTED:
740 case BT_CONFIG:
741 if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED) {
742 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
743 l2cap_send_disconn_req(chan, reason);
744 } else
745 l2cap_chan_del(chan, reason);
746 break;
747
748 case BT_CONNECT2:
749 if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED) {
750 if (conn->hcon->type == ACL_LINK)
751 l2cap_chan_connect_reject(chan);
752 else if (conn->hcon->type == LE_LINK)
753 l2cap_chan_le_connect_reject(chan);
754 }
755
756 l2cap_chan_del(chan, reason);
757 break;
758
759 case BT_CONNECT:
760 case BT_DISCONN:
761 l2cap_chan_del(chan, reason);
762 break;
763
764 default:
765 chan->ops->teardown(chan, 0);
766 break;
767 }
768}
769EXPORT_SYMBOL(l2cap_chan_close);
770
771static inline u8 l2cap_get_auth_type(struct l2cap_chan *chan)
772{
773 switch (chan->chan_type) {
774 case L2CAP_CHAN_RAW:
775 switch (chan->sec_level) {
776 case BT_SECURITY_HIGH:
777 case BT_SECURITY_FIPS:
778 return HCI_AT_DEDICATED_BONDING_MITM;
779 case BT_SECURITY_MEDIUM:
780 return HCI_AT_DEDICATED_BONDING;
781 default:
782 return HCI_AT_NO_BONDING;
783 }
784 break;
785 case L2CAP_CHAN_CONN_LESS:
786 if (chan->psm == cpu_to_le16(L2CAP_PSM_3DSP)) {
787 if (chan->sec_level == BT_SECURITY_LOW)
788 chan->sec_level = BT_SECURITY_SDP;
789 }
790 if (chan->sec_level == BT_SECURITY_HIGH ||
791 chan->sec_level == BT_SECURITY_FIPS)
792 return HCI_AT_NO_BONDING_MITM;
793 else
794 return HCI_AT_NO_BONDING;
795 break;
796 case L2CAP_CHAN_CONN_ORIENTED:
797 if (chan->psm == cpu_to_le16(L2CAP_PSM_SDP)) {
798 if (chan->sec_level == BT_SECURITY_LOW)
799 chan->sec_level = BT_SECURITY_SDP;
800
801 if (chan->sec_level == BT_SECURITY_HIGH ||
802 chan->sec_level == BT_SECURITY_FIPS)
803 return HCI_AT_NO_BONDING_MITM;
804 else
805 return HCI_AT_NO_BONDING;
806 }
807 /* fall through */
808 default:
809 switch (chan->sec_level) {
810 case BT_SECURITY_HIGH:
811 case BT_SECURITY_FIPS:
812 return HCI_AT_GENERAL_BONDING_MITM;
813 case BT_SECURITY_MEDIUM:
814 return HCI_AT_GENERAL_BONDING;
815 default:
816 return HCI_AT_NO_BONDING;
817 }
818 break;
819 }
820}
821
822/* Service level security */
823int l2cap_chan_check_security(struct l2cap_chan *chan, bool initiator)
824{
825 struct l2cap_conn *conn = chan->conn;
826 __u8 auth_type;
827
828 if (conn->hcon->type == LE_LINK)
829 return smp_conn_security(conn->hcon, chan->sec_level);
830
831 auth_type = l2cap_get_auth_type(chan);
832
833 return hci_conn_security(conn->hcon, chan->sec_level, auth_type,
834 initiator);
835}
836
837static u8 l2cap_get_ident(struct l2cap_conn *conn)
838{
839 u8 id;
840
841 /* Get next available identificator.
842 * 1 - 128 are used by kernel.
843 * 129 - 199 are reserved.
844 * 200 - 254 are used by utilities like l2ping, etc.
845 */
846
847 mutex_lock(&conn->ident_lock);
848
849 if (++conn->tx_ident > 128)
850 conn->tx_ident = 1;
851
852 id = conn->tx_ident;
853
854 mutex_unlock(&conn->ident_lock);
855
856 return id;
857}
858
859static void l2cap_send_cmd(struct l2cap_conn *conn, u8 ident, u8 code, u16 len,
860 void *data)
861{
862 struct sk_buff *skb = l2cap_build_cmd(conn, code, ident, len, data);
863 u8 flags;
864
865 BT_DBG("code 0x%2.2x", code);
866
867 if (!skb)
868 return;
869
870 /* Use NO_FLUSH if supported or we have an LE link (which does
871 * not support auto-flushing packets) */
872 if (lmp_no_flush_capable(conn->hcon->hdev) ||
873 conn->hcon->type == LE_LINK)
874 flags = ACL_START_NO_FLUSH;
875 else
876 flags = ACL_START;
877
878 bt_cb(skb)->force_active = BT_POWER_FORCE_ACTIVE_ON;
879 skb->priority = HCI_PRIO_MAX;
880
881 hci_send_acl(conn->hchan, skb, flags);
882}
883
884static bool __chan_is_moving(struct l2cap_chan *chan)
885{
886 return chan->move_state != L2CAP_MOVE_STABLE &&
887 chan->move_state != L2CAP_MOVE_WAIT_PREPARE;
888}
889
890static void l2cap_do_send(struct l2cap_chan *chan, struct sk_buff *skb)
891{
892 struct hci_conn *hcon = chan->conn->hcon;
893 u16 flags;
894
895 BT_DBG("chan %p, skb %p len %d priority %u", chan, skb, skb->len,
896 skb->priority);
897
898 if (chan->hs_hcon && !__chan_is_moving(chan)) {
899 if (chan->hs_hchan)
900 hci_send_acl(chan->hs_hchan, skb, ACL_COMPLETE);
901 else
902 kfree_skb(skb);
903
904 return;
905 }
906
907 /* Use NO_FLUSH for LE links (where this is the only option) or
908 * if the BR/EDR link supports it and flushing has not been
909 * explicitly requested (through FLAG_FLUSHABLE).
910 */
911 if (hcon->type == LE_LINK ||
912 (!test_bit(FLAG_FLUSHABLE, &chan->flags) &&
913 lmp_no_flush_capable(hcon->hdev)))
914 flags = ACL_START_NO_FLUSH;
915 else
916 flags = ACL_START;
917
918 bt_cb(skb)->force_active = test_bit(FLAG_FORCE_ACTIVE, &chan->flags);
919 hci_send_acl(chan->conn->hchan, skb, flags);
920}
921
922static void __unpack_enhanced_control(u16 enh, struct l2cap_ctrl *control)
923{
924 control->reqseq = (enh & L2CAP_CTRL_REQSEQ) >> L2CAP_CTRL_REQSEQ_SHIFT;
925 control->final = (enh & L2CAP_CTRL_FINAL) >> L2CAP_CTRL_FINAL_SHIFT;
926
927 if (enh & L2CAP_CTRL_FRAME_TYPE) {
928 /* S-Frame */
929 control->sframe = 1;
930 control->poll = (enh & L2CAP_CTRL_POLL) >> L2CAP_CTRL_POLL_SHIFT;
931 control->super = (enh & L2CAP_CTRL_SUPERVISE) >> L2CAP_CTRL_SUPER_SHIFT;
932
933 control->sar = 0;
934 control->txseq = 0;
935 } else {
936 /* I-Frame */
937 control->sframe = 0;
938 control->sar = (enh & L2CAP_CTRL_SAR) >> L2CAP_CTRL_SAR_SHIFT;
939 control->txseq = (enh & L2CAP_CTRL_TXSEQ) >> L2CAP_CTRL_TXSEQ_SHIFT;
940
941 control->poll = 0;
942 control->super = 0;
943 }
944}
945
946static void __unpack_extended_control(u32 ext, struct l2cap_ctrl *control)
947{
948 control->reqseq = (ext & L2CAP_EXT_CTRL_REQSEQ) >> L2CAP_EXT_CTRL_REQSEQ_SHIFT;
949 control->final = (ext & L2CAP_EXT_CTRL_FINAL) >> L2CAP_EXT_CTRL_FINAL_SHIFT;
950
951 if (ext & L2CAP_EXT_CTRL_FRAME_TYPE) {
952 /* S-Frame */
953 control->sframe = 1;
954 control->poll = (ext & L2CAP_EXT_CTRL_POLL) >> L2CAP_EXT_CTRL_POLL_SHIFT;
955 control->super = (ext & L2CAP_EXT_CTRL_SUPERVISE) >> L2CAP_EXT_CTRL_SUPER_SHIFT;
956
957 control->sar = 0;
958 control->txseq = 0;
959 } else {
960 /* I-Frame */
961 control->sframe = 0;
962 control->sar = (ext & L2CAP_EXT_CTRL_SAR) >> L2CAP_EXT_CTRL_SAR_SHIFT;
963 control->txseq = (ext & L2CAP_EXT_CTRL_TXSEQ) >> L2CAP_EXT_CTRL_TXSEQ_SHIFT;
964
965 control->poll = 0;
966 control->super = 0;
967 }
968}
969
970static inline void __unpack_control(struct l2cap_chan *chan,
971 struct sk_buff *skb)
972{
973 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) {
974 __unpack_extended_control(get_unaligned_le32(skb->data),
975 &bt_cb(skb)->l2cap);
976 skb_pull(skb, L2CAP_EXT_CTRL_SIZE);
977 } else {
978 __unpack_enhanced_control(get_unaligned_le16(skb->data),
979 &bt_cb(skb)->l2cap);
980 skb_pull(skb, L2CAP_ENH_CTRL_SIZE);
981 }
982}
983
984static u32 __pack_extended_control(struct l2cap_ctrl *control)
985{
986 u32 packed;
987
988 packed = control->reqseq << L2CAP_EXT_CTRL_REQSEQ_SHIFT;
989 packed |= control->final << L2CAP_EXT_CTRL_FINAL_SHIFT;
990
991 if (control->sframe) {
992 packed |= control->poll << L2CAP_EXT_CTRL_POLL_SHIFT;
993 packed |= control->super << L2CAP_EXT_CTRL_SUPER_SHIFT;
994 packed |= L2CAP_EXT_CTRL_FRAME_TYPE;
995 } else {
996 packed |= control->sar << L2CAP_EXT_CTRL_SAR_SHIFT;
997 packed |= control->txseq << L2CAP_EXT_CTRL_TXSEQ_SHIFT;
998 }
999
1000 return packed;
1001}
1002
1003static u16 __pack_enhanced_control(struct l2cap_ctrl *control)
1004{
1005 u16 packed;
1006
1007 packed = control->reqseq << L2CAP_CTRL_REQSEQ_SHIFT;
1008 packed |= control->final << L2CAP_CTRL_FINAL_SHIFT;
1009
1010 if (control->sframe) {
1011 packed |= control->poll << L2CAP_CTRL_POLL_SHIFT;
1012 packed |= control->super << L2CAP_CTRL_SUPER_SHIFT;
1013 packed |= L2CAP_CTRL_FRAME_TYPE;
1014 } else {
1015 packed |= control->sar << L2CAP_CTRL_SAR_SHIFT;
1016 packed |= control->txseq << L2CAP_CTRL_TXSEQ_SHIFT;
1017 }
1018
1019 return packed;
1020}
1021
1022static inline void __pack_control(struct l2cap_chan *chan,
1023 struct l2cap_ctrl *control,
1024 struct sk_buff *skb)
1025{
1026 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) {
1027 put_unaligned_le32(__pack_extended_control(control),
1028 skb->data + L2CAP_HDR_SIZE);
1029 } else {
1030 put_unaligned_le16(__pack_enhanced_control(control),
1031 skb->data + L2CAP_HDR_SIZE);
1032 }
1033}
1034
1035static inline unsigned int __ertm_hdr_size(struct l2cap_chan *chan)
1036{
1037 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
1038 return L2CAP_EXT_HDR_SIZE;
1039 else
1040 return L2CAP_ENH_HDR_SIZE;
1041}
1042
1043static struct sk_buff *l2cap_create_sframe_pdu(struct l2cap_chan *chan,
1044 u32 control)
1045{
1046 struct sk_buff *skb;
1047 struct l2cap_hdr *lh;
1048 int hlen = __ertm_hdr_size(chan);
1049
1050 if (chan->fcs == L2CAP_FCS_CRC16)
1051 hlen += L2CAP_FCS_SIZE;
1052
1053 skb = bt_skb_alloc(hlen, GFP_KERNEL);
1054
1055 if (!skb)
1056 return ERR_PTR(-ENOMEM);
1057
1058 lh = skb_put(skb, L2CAP_HDR_SIZE);
1059 lh->len = cpu_to_le16(hlen - L2CAP_HDR_SIZE);
1060 lh->cid = cpu_to_le16(chan->dcid);
1061
1062 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
1063 put_unaligned_le32(control, skb_put(skb, L2CAP_EXT_CTRL_SIZE));
1064 else
1065 put_unaligned_le16(control, skb_put(skb, L2CAP_ENH_CTRL_SIZE));
1066
1067 if (chan->fcs == L2CAP_FCS_CRC16) {
1068 u16 fcs = crc16(0, (u8 *)skb->data, skb->len);
1069 put_unaligned_le16(fcs, skb_put(skb, L2CAP_FCS_SIZE));
1070 }
1071
1072 skb->priority = HCI_PRIO_MAX;
1073 return skb;
1074}
1075
1076static void l2cap_send_sframe(struct l2cap_chan *chan,
1077 struct l2cap_ctrl *control)
1078{
1079 struct sk_buff *skb;
1080 u32 control_field;
1081
1082 BT_DBG("chan %p, control %p", chan, control);
1083
1084 if (!control->sframe)
1085 return;
1086
1087 if (__chan_is_moving(chan))
1088 return;
1089
1090 if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state) &&
1091 !control->poll)
1092 control->final = 1;
1093
1094 if (control->super == L2CAP_SUPER_RR)
1095 clear_bit(CONN_RNR_SENT, &chan->conn_state);
1096 else if (control->super == L2CAP_SUPER_RNR)
1097 set_bit(CONN_RNR_SENT, &chan->conn_state);
1098
1099 if (control->super != L2CAP_SUPER_SREJ) {
1100 chan->last_acked_seq = control->reqseq;
1101 __clear_ack_timer(chan);
1102 }
1103
1104 BT_DBG("reqseq %d, final %d, poll %d, super %d", control->reqseq,
1105 control->final, control->poll, control->super);
1106
1107 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
1108 control_field = __pack_extended_control(control);
1109 else
1110 control_field = __pack_enhanced_control(control);
1111
1112 skb = l2cap_create_sframe_pdu(chan, control_field);
1113 if (!IS_ERR(skb))
1114 l2cap_do_send(chan, skb);
1115}
1116
1117static void l2cap_send_rr_or_rnr(struct l2cap_chan *chan, bool poll)
1118{
1119 struct l2cap_ctrl control;
1120
1121 BT_DBG("chan %p, poll %d", chan, poll);
1122
1123 memset(&control, 0, sizeof(control));
1124 control.sframe = 1;
1125 control.poll = poll;
1126
1127 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state))
1128 control.super = L2CAP_SUPER_RNR;
1129 else
1130 control.super = L2CAP_SUPER_RR;
1131
1132 control.reqseq = chan->buffer_seq;
1133 l2cap_send_sframe(chan, &control);
1134}
1135
1136static inline int __l2cap_no_conn_pending(struct l2cap_chan *chan)
1137{
1138 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED)
1139 return true;
1140
1141 return !test_bit(CONF_CONNECT_PEND, &chan->conf_state);
1142}
1143
1144static bool __amp_capable(struct l2cap_chan *chan)
1145{
1146 struct l2cap_conn *conn = chan->conn;
1147 struct hci_dev *hdev;
1148 bool amp_available = false;
1149
1150 if (!(conn->local_fixed_chan & L2CAP_FC_A2MP))
1151 return false;
1152
1153 if (!(conn->remote_fixed_chan & L2CAP_FC_A2MP))
1154 return false;
1155
1156 read_lock(&hci_dev_list_lock);
1157 list_for_each_entry(hdev, &hci_dev_list, list) {
1158 if (hdev->amp_type != AMP_TYPE_BREDR &&
1159 test_bit(HCI_UP, &hdev->flags)) {
1160 amp_available = true;
1161 break;
1162 }
1163 }
1164 read_unlock(&hci_dev_list_lock);
1165
1166 if (chan->chan_policy == BT_CHANNEL_POLICY_AMP_PREFERRED)
1167 return amp_available;
1168
1169 return false;
1170}
1171
1172static bool l2cap_check_efs(struct l2cap_chan *chan)
1173{
1174 /* Check EFS parameters */
1175 return true;
1176}
1177
1178void l2cap_send_conn_req(struct l2cap_chan *chan)
1179{
1180 struct l2cap_conn *conn = chan->conn;
1181 struct l2cap_conn_req req;
1182
1183 req.scid = cpu_to_le16(chan->scid);
1184 req.psm = chan->psm;
1185
1186 chan->ident = l2cap_get_ident(conn);
1187
1188 set_bit(CONF_CONNECT_PEND, &chan->conf_state);
1189
1190 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_REQ, sizeof(req), &req);
1191}
1192
1193static void l2cap_send_create_chan_req(struct l2cap_chan *chan, u8 amp_id)
1194{
1195 struct l2cap_create_chan_req req;
1196 req.scid = cpu_to_le16(chan->scid);
1197 req.psm = chan->psm;
1198 req.amp_id = amp_id;
1199
1200 chan->ident = l2cap_get_ident(chan->conn);
1201
1202 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_CREATE_CHAN_REQ,
1203 sizeof(req), &req);
1204}
1205
1206static void l2cap_move_setup(struct l2cap_chan *chan)
1207{
1208 struct sk_buff *skb;
1209
1210 BT_DBG("chan %p", chan);
1211
1212 if (chan->mode != L2CAP_MODE_ERTM)
1213 return;
1214
1215 __clear_retrans_timer(chan);
1216 __clear_monitor_timer(chan);
1217 __clear_ack_timer(chan);
1218
1219 chan->retry_count = 0;
1220 skb_queue_walk(&chan->tx_q, skb) {
1221 if (bt_cb(skb)->l2cap.retries)
1222 bt_cb(skb)->l2cap.retries = 1;
1223 else
1224 break;
1225 }
1226
1227 chan->expected_tx_seq = chan->buffer_seq;
1228
1229 clear_bit(CONN_REJ_ACT, &chan->conn_state);
1230 clear_bit(CONN_SREJ_ACT, &chan->conn_state);
1231 l2cap_seq_list_clear(&chan->retrans_list);
1232 l2cap_seq_list_clear(&chan->srej_list);
1233 skb_queue_purge(&chan->srej_q);
1234
1235 chan->tx_state = L2CAP_TX_STATE_XMIT;
1236 chan->rx_state = L2CAP_RX_STATE_MOVE;
1237
1238 set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
1239}
1240
1241static void l2cap_move_done(struct l2cap_chan *chan)
1242{
1243 u8 move_role = chan->move_role;
1244 BT_DBG("chan %p", chan);
1245
1246 chan->move_state = L2CAP_MOVE_STABLE;
1247 chan->move_role = L2CAP_MOVE_ROLE_NONE;
1248
1249 if (chan->mode != L2CAP_MODE_ERTM)
1250 return;
1251
1252 switch (move_role) {
1253 case L2CAP_MOVE_ROLE_INITIATOR:
1254 l2cap_tx(chan, NULL, NULL, L2CAP_EV_EXPLICIT_POLL);
1255 chan->rx_state = L2CAP_RX_STATE_WAIT_F;
1256 break;
1257 case L2CAP_MOVE_ROLE_RESPONDER:
1258 chan->rx_state = L2CAP_RX_STATE_WAIT_P;
1259 break;
1260 }
1261}
1262
1263static void l2cap_chan_ready(struct l2cap_chan *chan)
1264{
1265 /* The channel may have already been flagged as connected in
1266 * case of receiving data before the L2CAP info req/rsp
1267 * procedure is complete.
1268 */
1269 if (chan->state == BT_CONNECTED)
1270 return;
1271
1272 /* This clears all conf flags, including CONF_NOT_COMPLETE */
1273 chan->conf_state = 0;
1274 __clear_chan_timer(chan);
1275
1276 if (chan->mode == L2CAP_MODE_LE_FLOWCTL && !chan->tx_credits)
1277 chan->ops->suspend(chan);
1278
1279 chan->state = BT_CONNECTED;
1280
1281 chan->ops->ready(chan);
1282}
1283
1284static void l2cap_le_connect(struct l2cap_chan *chan)
1285{
1286 struct l2cap_conn *conn = chan->conn;
1287 struct l2cap_le_conn_req req;
1288
1289 if (test_and_set_bit(FLAG_LE_CONN_REQ_SENT, &chan->flags))
1290 return;
1291
1292 l2cap_le_flowctl_init(chan, 0);
1293
1294 req.psm = chan->psm;
1295 req.scid = cpu_to_le16(chan->scid);
1296 req.mtu = cpu_to_le16(chan->imtu);
1297 req.mps = cpu_to_le16(chan->mps);
1298 req.credits = cpu_to_le16(chan->rx_credits);
1299
1300 chan->ident = l2cap_get_ident(conn);
1301
1302 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CONN_REQ,
1303 sizeof(req), &req);
1304}
1305
1306static void l2cap_le_start(struct l2cap_chan *chan)
1307{
1308 struct l2cap_conn *conn = chan->conn;
1309
1310 if (!smp_conn_security(conn->hcon, chan->sec_level))
1311 return;
1312
1313 if (!chan->psm) {
1314 l2cap_chan_ready(chan);
1315 return;
1316 }
1317
1318 if (chan->state == BT_CONNECT)
1319 l2cap_le_connect(chan);
1320}
1321
1322static void l2cap_start_connection(struct l2cap_chan *chan)
1323{
1324 if (__amp_capable(chan)) {
1325 BT_DBG("chan %p AMP capable: discover AMPs", chan);
1326 a2mp_discover_amp(chan);
1327 } else if (chan->conn->hcon->type == LE_LINK) {
1328 l2cap_le_start(chan);
1329 } else {
1330 l2cap_send_conn_req(chan);
1331 }
1332}
1333
1334static void l2cap_request_info(struct l2cap_conn *conn)
1335{
1336 struct l2cap_info_req req;
1337
1338 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT)
1339 return;
1340
1341 req.type = cpu_to_le16(L2CAP_IT_FEAT_MASK);
1342
1343 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_SENT;
1344 conn->info_ident = l2cap_get_ident(conn);
1345
1346 schedule_delayed_work(&conn->info_timer, L2CAP_INFO_TIMEOUT);
1347
1348 l2cap_send_cmd(conn, conn->info_ident, L2CAP_INFO_REQ,
1349 sizeof(req), &req);
1350}
1351
1352static bool l2cap_check_enc_key_size(struct hci_conn *hcon)
1353{
1354 /* The minimum encryption key size needs to be enforced by the
1355 * host stack before establishing any L2CAP connections. The
1356 * specification in theory allows a minimum of 1, but to align
1357 * BR/EDR and LE transports, a minimum of 7 is chosen.
1358 *
1359 * This check might also be called for unencrypted connections
1360 * that have no key size requirements. Ensure that the link is
1361 * actually encrypted before enforcing a key size.
1362 */
1363 return (!test_bit(HCI_CONN_ENCRYPT, &hcon->flags) ||
1364 hcon->enc_key_size >= hcon->hdev->min_enc_key_size);
1365}
1366
1367static void l2cap_do_start(struct l2cap_chan *chan)
1368{
1369 struct l2cap_conn *conn = chan->conn;
1370
1371 if (conn->hcon->type == LE_LINK) {
1372 l2cap_le_start(chan);
1373 return;
1374 }
1375
1376 if (!(conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT)) {
1377 l2cap_request_info(conn);
1378 return;
1379 }
1380
1381 if (!(conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE))
1382 return;
1383
1384 if (!l2cap_chan_check_security(chan, true) ||
1385 !__l2cap_no_conn_pending(chan))
1386 return;
1387
1388 if (l2cap_check_enc_key_size(conn->hcon))
1389 l2cap_start_connection(chan);
1390 else
1391 __set_chan_timer(chan, L2CAP_DISC_TIMEOUT);
1392}
1393
1394static inline int l2cap_mode_supported(__u8 mode, __u32 feat_mask)
1395{
1396 u32 local_feat_mask = l2cap_feat_mask;
1397 if (!disable_ertm)
1398 local_feat_mask |= L2CAP_FEAT_ERTM | L2CAP_FEAT_STREAMING;
1399
1400 switch (mode) {
1401 case L2CAP_MODE_ERTM:
1402 return L2CAP_FEAT_ERTM & feat_mask & local_feat_mask;
1403 case L2CAP_MODE_STREAMING:
1404 return L2CAP_FEAT_STREAMING & feat_mask & local_feat_mask;
1405 default:
1406 return 0x00;
1407 }
1408}
1409
1410static void l2cap_send_disconn_req(struct l2cap_chan *chan, int err)
1411{
1412 struct l2cap_conn *conn = chan->conn;
1413 struct l2cap_disconn_req req;
1414
1415 if (!conn)
1416 return;
1417
1418 if (chan->mode == L2CAP_MODE_ERTM && chan->state == BT_CONNECTED) {
1419 __clear_retrans_timer(chan);
1420 __clear_monitor_timer(chan);
1421 __clear_ack_timer(chan);
1422 }
1423
1424 if (chan->scid == L2CAP_CID_A2MP) {
1425 l2cap_state_change(chan, BT_DISCONN);
1426 return;
1427 }
1428
1429 req.dcid = cpu_to_le16(chan->dcid);
1430 req.scid = cpu_to_le16(chan->scid);
1431 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_DISCONN_REQ,
1432 sizeof(req), &req);
1433
1434 l2cap_state_change_and_error(chan, BT_DISCONN, err);
1435}
1436
1437/* ---- L2CAP connections ---- */
1438static void l2cap_conn_start(struct l2cap_conn *conn)
1439{
1440 struct l2cap_chan *chan, *tmp;
1441
1442 BT_DBG("conn %p", conn);
1443
1444 mutex_lock(&conn->chan_lock);
1445
1446 list_for_each_entry_safe(chan, tmp, &conn->chan_l, list) {
1447 l2cap_chan_lock(chan);
1448
1449 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
1450 l2cap_chan_ready(chan);
1451 l2cap_chan_unlock(chan);
1452 continue;
1453 }
1454
1455 if (chan->state == BT_CONNECT) {
1456 if (!l2cap_chan_check_security(chan, true) ||
1457 !__l2cap_no_conn_pending(chan)) {
1458 l2cap_chan_unlock(chan);
1459 continue;
1460 }
1461
1462 if (!l2cap_mode_supported(chan->mode, conn->feat_mask)
1463 && test_bit(CONF_STATE2_DEVICE,
1464 &chan->conf_state)) {
1465 l2cap_chan_close(chan, ECONNRESET);
1466 l2cap_chan_unlock(chan);
1467 continue;
1468 }
1469
1470 if (l2cap_check_enc_key_size(conn->hcon))
1471 l2cap_start_connection(chan);
1472 else
1473 l2cap_chan_close(chan, ECONNREFUSED);
1474
1475 } else if (chan->state == BT_CONNECT2) {
1476 struct l2cap_conn_rsp rsp;
1477 char buf[128];
1478 rsp.scid = cpu_to_le16(chan->dcid);
1479 rsp.dcid = cpu_to_le16(chan->scid);
1480
1481 if (l2cap_chan_check_security(chan, false)) {
1482 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
1483 rsp.result = cpu_to_le16(L2CAP_CR_PEND);
1484 rsp.status = cpu_to_le16(L2CAP_CS_AUTHOR_PEND);
1485 chan->ops->defer(chan);
1486
1487 } else {
1488 l2cap_state_change(chan, BT_CONFIG);
1489 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
1490 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
1491 }
1492 } else {
1493 rsp.result = cpu_to_le16(L2CAP_CR_PEND);
1494 rsp.status = cpu_to_le16(L2CAP_CS_AUTHEN_PEND);
1495 }
1496
1497 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP,
1498 sizeof(rsp), &rsp);
1499
1500 if (test_bit(CONF_REQ_SENT, &chan->conf_state) ||
1501 rsp.result != L2CAP_CR_SUCCESS) {
1502 l2cap_chan_unlock(chan);
1503 continue;
1504 }
1505
1506 set_bit(CONF_REQ_SENT, &chan->conf_state);
1507 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
1508 l2cap_build_conf_req(chan, buf, sizeof(buf)), buf);
1509 chan->num_conf_req++;
1510 }
1511
1512 l2cap_chan_unlock(chan);
1513 }
1514
1515 mutex_unlock(&conn->chan_lock);
1516}
1517
1518static void l2cap_le_conn_ready(struct l2cap_conn *conn)
1519{
1520 struct hci_conn *hcon = conn->hcon;
1521 struct hci_dev *hdev = hcon->hdev;
1522
1523 BT_DBG("%s conn %p", hdev->name, conn);
1524
1525 /* For outgoing pairing which doesn't necessarily have an
1526 * associated socket (e.g. mgmt_pair_device).
1527 */
1528 if (hcon->out)
1529 smp_conn_security(hcon, hcon->pending_sec_level);
1530
1531 /* For LE slave connections, make sure the connection interval
1532 * is in the range of the minium and maximum interval that has
1533 * been configured for this connection. If not, then trigger
1534 * the connection update procedure.
1535 */
1536 if (hcon->role == HCI_ROLE_SLAVE &&
1537 (hcon->le_conn_interval < hcon->le_conn_min_interval ||
1538 hcon->le_conn_interval > hcon->le_conn_max_interval)) {
1539 struct l2cap_conn_param_update_req req;
1540
1541 req.min = cpu_to_le16(hcon->le_conn_min_interval);
1542 req.max = cpu_to_le16(hcon->le_conn_max_interval);
1543 req.latency = cpu_to_le16(hcon->le_conn_latency);
1544 req.to_multiplier = cpu_to_le16(hcon->le_supv_timeout);
1545
1546 l2cap_send_cmd(conn, l2cap_get_ident(conn),
1547 L2CAP_CONN_PARAM_UPDATE_REQ, sizeof(req), &req);
1548 }
1549}
1550
1551static void l2cap_conn_ready(struct l2cap_conn *conn)
1552{
1553 struct l2cap_chan *chan;
1554 struct hci_conn *hcon = conn->hcon;
1555
1556 BT_DBG("conn %p", conn);
1557
1558 if (hcon->type == ACL_LINK)
1559 l2cap_request_info(conn);
1560
1561 mutex_lock(&conn->chan_lock);
1562
1563 list_for_each_entry(chan, &conn->chan_l, list) {
1564
1565 l2cap_chan_lock(chan);
1566
1567 if (chan->scid == L2CAP_CID_A2MP) {
1568 l2cap_chan_unlock(chan);
1569 continue;
1570 }
1571
1572 if (hcon->type == LE_LINK) {
1573 l2cap_le_start(chan);
1574 } else if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
1575 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE)
1576 l2cap_chan_ready(chan);
1577 } else if (chan->state == BT_CONNECT) {
1578 l2cap_do_start(chan);
1579 }
1580
1581 l2cap_chan_unlock(chan);
1582 }
1583
1584 mutex_unlock(&conn->chan_lock);
1585
1586 if (hcon->type == LE_LINK)
1587 l2cap_le_conn_ready(conn);
1588
1589 queue_work(hcon->hdev->workqueue, &conn->pending_rx_work);
1590}
1591
1592/* Notify sockets that we cannot guaranty reliability anymore */
1593static void l2cap_conn_unreliable(struct l2cap_conn *conn, int err)
1594{
1595 struct l2cap_chan *chan;
1596
1597 BT_DBG("conn %p", conn);
1598
1599 mutex_lock(&conn->chan_lock);
1600
1601 list_for_each_entry(chan, &conn->chan_l, list) {
1602 if (test_bit(FLAG_FORCE_RELIABLE, &chan->flags))
1603 l2cap_chan_set_err(chan, err);
1604 }
1605
1606 mutex_unlock(&conn->chan_lock);
1607}
1608
1609static void l2cap_info_timeout(struct work_struct *work)
1610{
1611 struct l2cap_conn *conn = container_of(work, struct l2cap_conn,
1612 info_timer.work);
1613
1614 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
1615 conn->info_ident = 0;
1616
1617 l2cap_conn_start(conn);
1618}
1619
1620/*
1621 * l2cap_user
1622 * External modules can register l2cap_user objects on l2cap_conn. The ->probe
1623 * callback is called during registration. The ->remove callback is called
1624 * during unregistration.
1625 * An l2cap_user object can either be explicitly unregistered or when the
1626 * underlying l2cap_conn object is deleted. This guarantees that l2cap->hcon,
1627 * l2cap->hchan, .. are valid as long as the remove callback hasn't been called.
1628 * External modules must own a reference to the l2cap_conn object if they intend
1629 * to call l2cap_unregister_user(). The l2cap_conn object might get destroyed at
1630 * any time if they don't.
1631 */
1632
1633int l2cap_register_user(struct l2cap_conn *conn, struct l2cap_user *user)
1634{
1635 struct hci_dev *hdev = conn->hcon->hdev;
1636 int ret;
1637
1638 /* We need to check whether l2cap_conn is registered. If it is not, we
1639 * must not register the l2cap_user. l2cap_conn_del() is unregisters
1640 * l2cap_conn objects, but doesn't provide its own locking. Instead, it
1641 * relies on the parent hci_conn object to be locked. This itself relies
1642 * on the hci_dev object to be locked. So we must lock the hci device
1643 * here, too. */
1644
1645 hci_dev_lock(hdev);
1646
1647 if (!list_empty(&user->list)) {
1648 ret = -EINVAL;
1649 goto out_unlock;
1650 }
1651
1652 /* conn->hchan is NULL after l2cap_conn_del() was called */
1653 if (!conn->hchan) {
1654 ret = -ENODEV;
1655 goto out_unlock;
1656 }
1657
1658 ret = user->probe(conn, user);
1659 if (ret)
1660 goto out_unlock;
1661
1662 list_add(&user->list, &conn->users);
1663 ret = 0;
1664
1665out_unlock:
1666 hci_dev_unlock(hdev);
1667 return ret;
1668}
1669EXPORT_SYMBOL(l2cap_register_user);
1670
1671void l2cap_unregister_user(struct l2cap_conn *conn, struct l2cap_user *user)
1672{
1673 struct hci_dev *hdev = conn->hcon->hdev;
1674
1675 hci_dev_lock(hdev);
1676
1677 if (list_empty(&user->list))
1678 goto out_unlock;
1679
1680 list_del_init(&user->list);
1681 user->remove(conn, user);
1682
1683out_unlock:
1684 hci_dev_unlock(hdev);
1685}
1686EXPORT_SYMBOL(l2cap_unregister_user);
1687
1688static void l2cap_unregister_all_users(struct l2cap_conn *conn)
1689{
1690 struct l2cap_user *user;
1691
1692 while (!list_empty(&conn->users)) {
1693 user = list_first_entry(&conn->users, struct l2cap_user, list);
1694 list_del_init(&user->list);
1695 user->remove(conn, user);
1696 }
1697}
1698
1699static void l2cap_conn_del(struct hci_conn *hcon, int err)
1700{
1701 struct l2cap_conn *conn = hcon->l2cap_data;
1702 struct l2cap_chan *chan, *l;
1703
1704 if (!conn)
1705 return;
1706
1707 BT_DBG("hcon %p conn %p, err %d", hcon, conn, err);
1708
1709 kfree_skb(conn->rx_skb);
1710
1711 skb_queue_purge(&conn->pending_rx);
1712
1713 /* We can not call flush_work(&conn->pending_rx_work) here since we
1714 * might block if we are running on a worker from the same workqueue
1715 * pending_rx_work is waiting on.
1716 */
1717 if (work_pending(&conn->pending_rx_work))
1718 cancel_work_sync(&conn->pending_rx_work);
1719
1720 if (work_pending(&conn->id_addr_update_work))
1721 cancel_work_sync(&conn->id_addr_update_work);
1722
1723 l2cap_unregister_all_users(conn);
1724
1725 /* Force the connection to be immediately dropped */
1726 hcon->disc_timeout = 0;
1727
1728 mutex_lock(&conn->chan_lock);
1729
1730 /* Kill channels */
1731 list_for_each_entry_safe(chan, l, &conn->chan_l, list) {
1732 l2cap_chan_hold(chan);
1733 l2cap_chan_lock(chan);
1734
1735 l2cap_chan_del(chan, err);
1736
1737 l2cap_chan_unlock(chan);
1738
1739 chan->ops->close(chan);
1740 l2cap_chan_put(chan);
1741 }
1742
1743 mutex_unlock(&conn->chan_lock);
1744
1745 hci_chan_del(conn->hchan);
1746
1747 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT)
1748 cancel_delayed_work_sync(&conn->info_timer);
1749
1750 hcon->l2cap_data = NULL;
1751 conn->hchan = NULL;
1752 l2cap_conn_put(conn);
1753}
1754
1755static void l2cap_conn_free(struct kref *ref)
1756{
1757 struct l2cap_conn *conn = container_of(ref, struct l2cap_conn, ref);
1758
1759 hci_conn_put(conn->hcon);
1760 kfree(conn);
1761}
1762
1763struct l2cap_conn *l2cap_conn_get(struct l2cap_conn *conn)
1764{
1765 kref_get(&conn->ref);
1766 return conn;
1767}
1768EXPORT_SYMBOL(l2cap_conn_get);
1769
1770void l2cap_conn_put(struct l2cap_conn *conn)
1771{
1772 kref_put(&conn->ref, l2cap_conn_free);
1773}
1774EXPORT_SYMBOL(l2cap_conn_put);
1775
1776/* ---- Socket interface ---- */
1777
1778/* Find socket with psm and source / destination bdaddr.
1779 * Returns closest match.
1780 */
1781static struct l2cap_chan *l2cap_global_chan_by_psm(int state, __le16 psm,
1782 bdaddr_t *src,
1783 bdaddr_t *dst,
1784 u8 link_type)
1785{
1786 struct l2cap_chan *c, *c1 = NULL;
1787
1788 read_lock(&chan_list_lock);
1789
1790 list_for_each_entry(c, &chan_list, global_l) {
1791 if (state && c->state != state)
1792 continue;
1793
1794 if (link_type == ACL_LINK && c->src_type != BDADDR_BREDR)
1795 continue;
1796
1797 if (link_type == LE_LINK && c->src_type == BDADDR_BREDR)
1798 continue;
1799
1800 if (c->psm == psm) {
1801 int src_match, dst_match;
1802 int src_any, dst_any;
1803
1804 /* Exact match. */
1805 src_match = !bacmp(&c->src, src);
1806 dst_match = !bacmp(&c->dst, dst);
1807 if (src_match && dst_match) {
1808 l2cap_chan_hold(c);
1809 read_unlock(&chan_list_lock);
1810 return c;
1811 }
1812
1813 /* Closest match */
1814 src_any = !bacmp(&c->src, BDADDR_ANY);
1815 dst_any = !bacmp(&c->dst, BDADDR_ANY);
1816 if ((src_match && dst_any) || (src_any && dst_match) ||
1817 (src_any && dst_any))
1818 c1 = c;
1819 }
1820 }
1821
1822 if (c1)
1823 l2cap_chan_hold(c1);
1824
1825 read_unlock(&chan_list_lock);
1826
1827 return c1;
1828}
1829
1830static void l2cap_monitor_timeout(struct work_struct *work)
1831{
1832 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
1833 monitor_timer.work);
1834
1835 BT_DBG("chan %p", chan);
1836
1837 l2cap_chan_lock(chan);
1838
1839 if (!chan->conn) {
1840 l2cap_chan_unlock(chan);
1841 l2cap_chan_put(chan);
1842 return;
1843 }
1844
1845 l2cap_tx(chan, NULL, NULL, L2CAP_EV_MONITOR_TO);
1846
1847 l2cap_chan_unlock(chan);
1848 l2cap_chan_put(chan);
1849}
1850
1851static void l2cap_retrans_timeout(struct work_struct *work)
1852{
1853 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
1854 retrans_timer.work);
1855
1856 BT_DBG("chan %p", chan);
1857
1858 l2cap_chan_lock(chan);
1859
1860 if (!chan->conn) {
1861 l2cap_chan_unlock(chan);
1862 l2cap_chan_put(chan);
1863 return;
1864 }
1865
1866 l2cap_tx(chan, NULL, NULL, L2CAP_EV_RETRANS_TO);
1867 l2cap_chan_unlock(chan);
1868 l2cap_chan_put(chan);
1869}
1870
1871static void l2cap_streaming_send(struct l2cap_chan *chan,
1872 struct sk_buff_head *skbs)
1873{
1874 struct sk_buff *skb;
1875 struct l2cap_ctrl *control;
1876
1877 BT_DBG("chan %p, skbs %p", chan, skbs);
1878
1879 if (__chan_is_moving(chan))
1880 return;
1881
1882 skb_queue_splice_tail_init(skbs, &chan->tx_q);
1883
1884 while (!skb_queue_empty(&chan->tx_q)) {
1885
1886 skb = skb_dequeue(&chan->tx_q);
1887
1888 bt_cb(skb)->l2cap.retries = 1;
1889 control = &bt_cb(skb)->l2cap;
1890
1891 control->reqseq = 0;
1892 control->txseq = chan->next_tx_seq;
1893
1894 __pack_control(chan, control, skb);
1895
1896 if (chan->fcs == L2CAP_FCS_CRC16) {
1897 u16 fcs = crc16(0, (u8 *) skb->data, skb->len);
1898 put_unaligned_le16(fcs, skb_put(skb, L2CAP_FCS_SIZE));
1899 }
1900
1901 l2cap_do_send(chan, skb);
1902
1903 BT_DBG("Sent txseq %u", control->txseq);
1904
1905 chan->next_tx_seq = __next_seq(chan, chan->next_tx_seq);
1906 chan->frames_sent++;
1907 }
1908}
1909
1910static int l2cap_ertm_send(struct l2cap_chan *chan)
1911{
1912 struct sk_buff *skb, *tx_skb;
1913 struct l2cap_ctrl *control;
1914 int sent = 0;
1915
1916 BT_DBG("chan %p", chan);
1917
1918 if (chan->state != BT_CONNECTED)
1919 return -ENOTCONN;
1920
1921 if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state))
1922 return 0;
1923
1924 if (__chan_is_moving(chan))
1925 return 0;
1926
1927 while (chan->tx_send_head &&
1928 chan->unacked_frames < chan->remote_tx_win &&
1929 chan->tx_state == L2CAP_TX_STATE_XMIT) {
1930
1931 skb = chan->tx_send_head;
1932
1933 bt_cb(skb)->l2cap.retries = 1;
1934 control = &bt_cb(skb)->l2cap;
1935
1936 if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state))
1937 control->final = 1;
1938
1939 control->reqseq = chan->buffer_seq;
1940 chan->last_acked_seq = chan->buffer_seq;
1941 control->txseq = chan->next_tx_seq;
1942
1943 __pack_control(chan, control, skb);
1944
1945 if (chan->fcs == L2CAP_FCS_CRC16) {
1946 u16 fcs = crc16(0, (u8 *) skb->data, skb->len);
1947 put_unaligned_le16(fcs, skb_put(skb, L2CAP_FCS_SIZE));
1948 }
1949
1950 /* Clone after data has been modified. Data is assumed to be
1951 read-only (for locking purposes) on cloned sk_buffs.
1952 */
1953 tx_skb = skb_clone(skb, GFP_KERNEL);
1954
1955 if (!tx_skb)
1956 break;
1957
1958 __set_retrans_timer(chan);
1959
1960 chan->next_tx_seq = __next_seq(chan, chan->next_tx_seq);
1961 chan->unacked_frames++;
1962 chan->frames_sent++;
1963 sent++;
1964
1965 if (skb_queue_is_last(&chan->tx_q, skb))
1966 chan->tx_send_head = NULL;
1967 else
1968 chan->tx_send_head = skb_queue_next(&chan->tx_q, skb);
1969
1970 l2cap_do_send(chan, tx_skb);
1971 BT_DBG("Sent txseq %u", control->txseq);
1972 }
1973
1974 BT_DBG("Sent %d, %u unacked, %u in ERTM queue", sent,
1975 chan->unacked_frames, skb_queue_len(&chan->tx_q));
1976
1977 return sent;
1978}
1979
1980static void l2cap_ertm_resend(struct l2cap_chan *chan)
1981{
1982 struct l2cap_ctrl control;
1983 struct sk_buff *skb;
1984 struct sk_buff *tx_skb;
1985 u16 seq;
1986
1987 BT_DBG("chan %p", chan);
1988
1989 if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state))
1990 return;
1991
1992 if (__chan_is_moving(chan))
1993 return;
1994
1995 while (chan->retrans_list.head != L2CAP_SEQ_LIST_CLEAR) {
1996 seq = l2cap_seq_list_pop(&chan->retrans_list);
1997
1998 skb = l2cap_ertm_seq_in_queue(&chan->tx_q, seq);
1999 if (!skb) {
2000 BT_DBG("Error: Can't retransmit seq %d, frame missing",
2001 seq);
2002 continue;
2003 }
2004
2005 bt_cb(skb)->l2cap.retries++;
2006 control = bt_cb(skb)->l2cap;
2007
2008 if (chan->max_tx != 0 &&
2009 bt_cb(skb)->l2cap.retries > chan->max_tx) {
2010 BT_DBG("Retry limit exceeded (%d)", chan->max_tx);
2011 l2cap_send_disconn_req(chan, ECONNRESET);
2012 l2cap_seq_list_clear(&chan->retrans_list);
2013 break;
2014 }
2015
2016 control.reqseq = chan->buffer_seq;
2017 if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state))
2018 control.final = 1;
2019 else
2020 control.final = 0;
2021
2022 if (skb_cloned(skb)) {
2023 /* Cloned sk_buffs are read-only, so we need a
2024 * writeable copy
2025 */
2026 tx_skb = skb_copy(skb, GFP_KERNEL);
2027 } else {
2028 tx_skb = skb_clone(skb, GFP_KERNEL);
2029 }
2030
2031 if (!tx_skb) {
2032 l2cap_seq_list_clear(&chan->retrans_list);
2033 break;
2034 }
2035
2036 /* Update skb contents */
2037 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) {
2038 put_unaligned_le32(__pack_extended_control(&control),
2039 tx_skb->data + L2CAP_HDR_SIZE);
2040 } else {
2041 put_unaligned_le16(__pack_enhanced_control(&control),
2042 tx_skb->data + L2CAP_HDR_SIZE);
2043 }
2044
2045 /* Update FCS */
2046 if (chan->fcs == L2CAP_FCS_CRC16) {
2047 u16 fcs = crc16(0, (u8 *) tx_skb->data,
2048 tx_skb->len - L2CAP_FCS_SIZE);
2049 put_unaligned_le16(fcs, skb_tail_pointer(tx_skb) -
2050 L2CAP_FCS_SIZE);
2051 }
2052
2053 l2cap_do_send(chan, tx_skb);
2054
2055 BT_DBG("Resent txseq %d", control.txseq);
2056
2057 chan->last_acked_seq = chan->buffer_seq;
2058 }
2059}
2060
2061static void l2cap_retransmit(struct l2cap_chan *chan,
2062 struct l2cap_ctrl *control)
2063{
2064 BT_DBG("chan %p, control %p", chan, control);
2065
2066 l2cap_seq_list_append(&chan->retrans_list, control->reqseq);
2067 l2cap_ertm_resend(chan);
2068}
2069
2070static void l2cap_retransmit_all(struct l2cap_chan *chan,
2071 struct l2cap_ctrl *control)
2072{
2073 struct sk_buff *skb;
2074
2075 BT_DBG("chan %p, control %p", chan, control);
2076
2077 if (control->poll)
2078 set_bit(CONN_SEND_FBIT, &chan->conn_state);
2079
2080 l2cap_seq_list_clear(&chan->retrans_list);
2081
2082 if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state))
2083 return;
2084
2085 if (chan->unacked_frames) {
2086 skb_queue_walk(&chan->tx_q, skb) {
2087 if (bt_cb(skb)->l2cap.txseq == control->reqseq ||
2088 skb == chan->tx_send_head)
2089 break;
2090 }
2091
2092 skb_queue_walk_from(&chan->tx_q, skb) {
2093 if (skb == chan->tx_send_head)
2094 break;
2095
2096 l2cap_seq_list_append(&chan->retrans_list,
2097 bt_cb(skb)->l2cap.txseq);
2098 }
2099
2100 l2cap_ertm_resend(chan);
2101 }
2102}
2103
2104static void l2cap_send_ack(struct l2cap_chan *chan)
2105{
2106 struct l2cap_ctrl control;
2107 u16 frames_to_ack = __seq_offset(chan, chan->buffer_seq,
2108 chan->last_acked_seq);
2109 int threshold;
2110
2111 BT_DBG("chan %p last_acked_seq %d buffer_seq %d",
2112 chan, chan->last_acked_seq, chan->buffer_seq);
2113
2114 memset(&control, 0, sizeof(control));
2115 control.sframe = 1;
2116
2117 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state) &&
2118 chan->rx_state == L2CAP_RX_STATE_RECV) {
2119 __clear_ack_timer(chan);
2120 control.super = L2CAP_SUPER_RNR;
2121 control.reqseq = chan->buffer_seq;
2122 l2cap_send_sframe(chan, &control);
2123 } else {
2124 if (!test_bit(CONN_REMOTE_BUSY, &chan->conn_state)) {
2125 l2cap_ertm_send(chan);
2126 /* If any i-frames were sent, they included an ack */
2127 if (chan->buffer_seq == chan->last_acked_seq)
2128 frames_to_ack = 0;
2129 }
2130
2131 /* Ack now if the window is 3/4ths full.
2132 * Calculate without mul or div
2133 */
2134 threshold = chan->ack_win;
2135 threshold += threshold << 1;
2136 threshold >>= 2;
2137
2138 BT_DBG("frames_to_ack %u, threshold %d", frames_to_ack,
2139 threshold);
2140
2141 if (frames_to_ack >= threshold) {
2142 __clear_ack_timer(chan);
2143 control.super = L2CAP_SUPER_RR;
2144 control.reqseq = chan->buffer_seq;
2145 l2cap_send_sframe(chan, &control);
2146 frames_to_ack = 0;
2147 }
2148
2149 if (frames_to_ack)
2150 __set_ack_timer(chan);
2151 }
2152}
2153
2154static inline int l2cap_skbuff_fromiovec(struct l2cap_chan *chan,
2155 struct msghdr *msg, int len,
2156 int count, struct sk_buff *skb)
2157{
2158 struct l2cap_conn *conn = chan->conn;
2159 struct sk_buff **frag;
2160 int sent = 0;
2161
2162 if (!copy_from_iter_full(skb_put(skb, count), count, &msg->msg_iter))
2163 return -EFAULT;
2164
2165 sent += count;
2166 len -= count;
2167
2168 /* Continuation fragments (no L2CAP header) */
2169 frag = &skb_shinfo(skb)->frag_list;
2170 while (len) {
2171 struct sk_buff *tmp;
2172
2173 count = min_t(unsigned int, conn->mtu, len);
2174
2175 tmp = chan->ops->alloc_skb(chan, 0, count,
2176 msg->msg_flags & MSG_DONTWAIT);
2177 if (IS_ERR(tmp))
2178 return PTR_ERR(tmp);
2179
2180 *frag = tmp;
2181
2182 if (!copy_from_iter_full(skb_put(*frag, count), count,
2183 &msg->msg_iter))
2184 return -EFAULT;
2185
2186 sent += count;
2187 len -= count;
2188
2189 skb->len += (*frag)->len;
2190 skb->data_len += (*frag)->len;
2191
2192 frag = &(*frag)->next;
2193 }
2194
2195 return sent;
2196}
2197
2198static struct sk_buff *l2cap_create_connless_pdu(struct l2cap_chan *chan,
2199 struct msghdr *msg, size_t len)
2200{
2201 struct l2cap_conn *conn = chan->conn;
2202 struct sk_buff *skb;
2203 int err, count, hlen = L2CAP_HDR_SIZE + L2CAP_PSMLEN_SIZE;
2204 struct l2cap_hdr *lh;
2205
2206 BT_DBG("chan %p psm 0x%2.2x len %zu", chan,
2207 __le16_to_cpu(chan->psm), len);
2208
2209 count = min_t(unsigned int, (conn->mtu - hlen), len);
2210
2211 skb = chan->ops->alloc_skb(chan, hlen, count,
2212 msg->msg_flags & MSG_DONTWAIT);
2213 if (IS_ERR(skb))
2214 return skb;
2215
2216 /* Create L2CAP header */
2217 lh = skb_put(skb, L2CAP_HDR_SIZE);
2218 lh->cid = cpu_to_le16(chan->dcid);
2219 lh->len = cpu_to_le16(len + L2CAP_PSMLEN_SIZE);
2220 put_unaligned(chan->psm, (__le16 *) skb_put(skb, L2CAP_PSMLEN_SIZE));
2221
2222 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2223 if (unlikely(err < 0)) {
2224 kfree_skb(skb);
2225 return ERR_PTR(err);
2226 }
2227 return skb;
2228}
2229
2230static struct sk_buff *l2cap_create_basic_pdu(struct l2cap_chan *chan,
2231 struct msghdr *msg, size_t len)
2232{
2233 struct l2cap_conn *conn = chan->conn;
2234 struct sk_buff *skb;
2235 int err, count;
2236 struct l2cap_hdr *lh;
2237
2238 BT_DBG("chan %p len %zu", chan, len);
2239
2240 count = min_t(unsigned int, (conn->mtu - L2CAP_HDR_SIZE), len);
2241
2242 skb = chan->ops->alloc_skb(chan, L2CAP_HDR_SIZE, count,
2243 msg->msg_flags & MSG_DONTWAIT);
2244 if (IS_ERR(skb))
2245 return skb;
2246
2247 /* Create L2CAP header */
2248 lh = skb_put(skb, L2CAP_HDR_SIZE);
2249 lh->cid = cpu_to_le16(chan->dcid);
2250 lh->len = cpu_to_le16(len);
2251
2252 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2253 if (unlikely(err < 0)) {
2254 kfree_skb(skb);
2255 return ERR_PTR(err);
2256 }
2257 return skb;
2258}
2259
2260static struct sk_buff *l2cap_create_iframe_pdu(struct l2cap_chan *chan,
2261 struct msghdr *msg, size_t len,
2262 u16 sdulen)
2263{
2264 struct l2cap_conn *conn = chan->conn;
2265 struct sk_buff *skb;
2266 int err, count, hlen;
2267 struct l2cap_hdr *lh;
2268
2269 BT_DBG("chan %p len %zu", chan, len);
2270
2271 if (!conn)
2272 return ERR_PTR(-ENOTCONN);
2273
2274 hlen = __ertm_hdr_size(chan);
2275
2276 if (sdulen)
2277 hlen += L2CAP_SDULEN_SIZE;
2278
2279 if (chan->fcs == L2CAP_FCS_CRC16)
2280 hlen += L2CAP_FCS_SIZE;
2281
2282 count = min_t(unsigned int, (conn->mtu - hlen), len);
2283
2284 skb = chan->ops->alloc_skb(chan, hlen, count,
2285 msg->msg_flags & MSG_DONTWAIT);
2286 if (IS_ERR(skb))
2287 return skb;
2288
2289 /* Create L2CAP header */
2290 lh = skb_put(skb, L2CAP_HDR_SIZE);
2291 lh->cid = cpu_to_le16(chan->dcid);
2292 lh->len = cpu_to_le16(len + (hlen - L2CAP_HDR_SIZE));
2293
2294 /* Control header is populated later */
2295 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
2296 put_unaligned_le32(0, skb_put(skb, L2CAP_EXT_CTRL_SIZE));
2297 else
2298 put_unaligned_le16(0, skb_put(skb, L2CAP_ENH_CTRL_SIZE));
2299
2300 if (sdulen)
2301 put_unaligned_le16(sdulen, skb_put(skb, L2CAP_SDULEN_SIZE));
2302
2303 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2304 if (unlikely(err < 0)) {
2305 kfree_skb(skb);
2306 return ERR_PTR(err);
2307 }
2308
2309 bt_cb(skb)->l2cap.fcs = chan->fcs;
2310 bt_cb(skb)->l2cap.retries = 0;
2311 return skb;
2312}
2313
2314static int l2cap_segment_sdu(struct l2cap_chan *chan,
2315 struct sk_buff_head *seg_queue,
2316 struct msghdr *msg, size_t len)
2317{
2318 struct sk_buff *skb;
2319 u16 sdu_len;
2320 size_t pdu_len;
2321 u8 sar;
2322
2323 BT_DBG("chan %p, msg %p, len %zu", chan, msg, len);
2324
2325 /* It is critical that ERTM PDUs fit in a single HCI fragment,
2326 * so fragmented skbs are not used. The HCI layer's handling
2327 * of fragmented skbs is not compatible with ERTM's queueing.
2328 */
2329
2330 /* PDU size is derived from the HCI MTU */
2331 pdu_len = chan->conn->mtu;
2332
2333 /* Constrain PDU size for BR/EDR connections */
2334 if (!chan->hs_hcon)
2335 pdu_len = min_t(size_t, pdu_len, L2CAP_BREDR_MAX_PAYLOAD);
2336
2337 /* Adjust for largest possible L2CAP overhead. */
2338 if (chan->fcs)
2339 pdu_len -= L2CAP_FCS_SIZE;
2340
2341 pdu_len -= __ertm_hdr_size(chan);
2342
2343 /* Remote device may have requested smaller PDUs */
2344 pdu_len = min_t(size_t, pdu_len, chan->remote_mps);
2345
2346 if (len <= pdu_len) {
2347 sar = L2CAP_SAR_UNSEGMENTED;
2348 sdu_len = 0;
2349 pdu_len = len;
2350 } else {
2351 sar = L2CAP_SAR_START;
2352 sdu_len = len;
2353 }
2354
2355 while (len > 0) {
2356 skb = l2cap_create_iframe_pdu(chan, msg, pdu_len, sdu_len);
2357
2358 if (IS_ERR(skb)) {
2359 __skb_queue_purge(seg_queue);
2360 return PTR_ERR(skb);
2361 }
2362
2363 bt_cb(skb)->l2cap.sar = sar;
2364 __skb_queue_tail(seg_queue, skb);
2365
2366 len -= pdu_len;
2367 if (sdu_len)
2368 sdu_len = 0;
2369
2370 if (len <= pdu_len) {
2371 sar = L2CAP_SAR_END;
2372 pdu_len = len;
2373 } else {
2374 sar = L2CAP_SAR_CONTINUE;
2375 }
2376 }
2377
2378 return 0;
2379}
2380
2381static struct sk_buff *l2cap_create_le_flowctl_pdu(struct l2cap_chan *chan,
2382 struct msghdr *msg,
2383 size_t len, u16 sdulen)
2384{
2385 struct l2cap_conn *conn = chan->conn;
2386 struct sk_buff *skb;
2387 int err, count, hlen;
2388 struct l2cap_hdr *lh;
2389
2390 BT_DBG("chan %p len %zu", chan, len);
2391
2392 if (!conn)
2393 return ERR_PTR(-ENOTCONN);
2394
2395 hlen = L2CAP_HDR_SIZE;
2396
2397 if (sdulen)
2398 hlen += L2CAP_SDULEN_SIZE;
2399
2400 count = min_t(unsigned int, (conn->mtu - hlen), len);
2401
2402 skb = chan->ops->alloc_skb(chan, hlen, count,
2403 msg->msg_flags & MSG_DONTWAIT);
2404 if (IS_ERR(skb))
2405 return skb;
2406
2407 /* Create L2CAP header */
2408 lh = skb_put(skb, L2CAP_HDR_SIZE);
2409 lh->cid = cpu_to_le16(chan->dcid);
2410 lh->len = cpu_to_le16(len + (hlen - L2CAP_HDR_SIZE));
2411
2412 if (sdulen)
2413 put_unaligned_le16(sdulen, skb_put(skb, L2CAP_SDULEN_SIZE));
2414
2415 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2416 if (unlikely(err < 0)) {
2417 kfree_skb(skb);
2418 return ERR_PTR(err);
2419 }
2420
2421 return skb;
2422}
2423
2424static int l2cap_segment_le_sdu(struct l2cap_chan *chan,
2425 struct sk_buff_head *seg_queue,
2426 struct msghdr *msg, size_t len)
2427{
2428 struct sk_buff *skb;
2429 size_t pdu_len;
2430 u16 sdu_len;
2431
2432 BT_DBG("chan %p, msg %p, len %zu", chan, msg, len);
2433
2434 sdu_len = len;
2435 pdu_len = chan->remote_mps - L2CAP_SDULEN_SIZE;
2436
2437 while (len > 0) {
2438 if (len <= pdu_len)
2439 pdu_len = len;
2440
2441 skb = l2cap_create_le_flowctl_pdu(chan, msg, pdu_len, sdu_len);
2442 if (IS_ERR(skb)) {
2443 __skb_queue_purge(seg_queue);
2444 return PTR_ERR(skb);
2445 }
2446
2447 __skb_queue_tail(seg_queue, skb);
2448
2449 len -= pdu_len;
2450
2451 if (sdu_len) {
2452 sdu_len = 0;
2453 pdu_len += L2CAP_SDULEN_SIZE;
2454 }
2455 }
2456
2457 return 0;
2458}
2459
2460static void l2cap_le_flowctl_send(struct l2cap_chan *chan)
2461{
2462 int sent = 0;
2463
2464 BT_DBG("chan %p", chan);
2465
2466 while (chan->tx_credits && !skb_queue_empty(&chan->tx_q)) {
2467 l2cap_do_send(chan, skb_dequeue(&chan->tx_q));
2468 chan->tx_credits--;
2469 sent++;
2470 }
2471
2472 BT_DBG("Sent %d credits %u queued %u", sent, chan->tx_credits,
2473 skb_queue_len(&chan->tx_q));
2474}
2475
2476int l2cap_chan_send(struct l2cap_chan *chan, struct msghdr *msg, size_t len)
2477{
2478 struct sk_buff *skb;
2479 int err;
2480 struct sk_buff_head seg_queue;
2481
2482 if (!chan->conn)
2483 return -ENOTCONN;
2484
2485 /* Connectionless channel */
2486 if (chan->chan_type == L2CAP_CHAN_CONN_LESS) {
2487 skb = l2cap_create_connless_pdu(chan, msg, len);
2488 if (IS_ERR(skb))
2489 return PTR_ERR(skb);
2490
2491 /* Channel lock is released before requesting new skb and then
2492 * reacquired thus we need to recheck channel state.
2493 */
2494 if (chan->state != BT_CONNECTED) {
2495 kfree_skb(skb);
2496 return -ENOTCONN;
2497 }
2498
2499 l2cap_do_send(chan, skb);
2500 return len;
2501 }
2502
2503 switch (chan->mode) {
2504 case L2CAP_MODE_LE_FLOWCTL:
2505 /* Check outgoing MTU */
2506 if (len > chan->omtu)
2507 return -EMSGSIZE;
2508
2509 __skb_queue_head_init(&seg_queue);
2510
2511 err = l2cap_segment_le_sdu(chan, &seg_queue, msg, len);
2512
2513 if (chan->state != BT_CONNECTED) {
2514 __skb_queue_purge(&seg_queue);
2515 err = -ENOTCONN;
2516 }
2517
2518 if (err)
2519 return err;
2520
2521 skb_queue_splice_tail_init(&seg_queue, &chan->tx_q);
2522
2523 l2cap_le_flowctl_send(chan);
2524
2525 if (!chan->tx_credits)
2526 chan->ops->suspend(chan);
2527
2528 err = len;
2529
2530 break;
2531
2532 case L2CAP_MODE_BASIC:
2533 /* Check outgoing MTU */
2534 if (len > chan->omtu)
2535 return -EMSGSIZE;
2536
2537 /* Create a basic PDU */
2538 skb = l2cap_create_basic_pdu(chan, msg, len);
2539 if (IS_ERR(skb))
2540 return PTR_ERR(skb);
2541
2542 /* Channel lock is released before requesting new skb and then
2543 * reacquired thus we need to recheck channel state.
2544 */
2545 if (chan->state != BT_CONNECTED) {
2546 kfree_skb(skb);
2547 return -ENOTCONN;
2548 }
2549
2550 l2cap_do_send(chan, skb);
2551 err = len;
2552 break;
2553
2554 case L2CAP_MODE_ERTM:
2555 case L2CAP_MODE_STREAMING:
2556 /* Check outgoing MTU */
2557 if (len > chan->omtu) {
2558 err = -EMSGSIZE;
2559 break;
2560 }
2561
2562 __skb_queue_head_init(&seg_queue);
2563
2564 /* Do segmentation before calling in to the state machine,
2565 * since it's possible to block while waiting for memory
2566 * allocation.
2567 */
2568 err = l2cap_segment_sdu(chan, &seg_queue, msg, len);
2569
2570 /* The channel could have been closed while segmenting,
2571 * check that it is still connected.
2572 */
2573 if (chan->state != BT_CONNECTED) {
2574 __skb_queue_purge(&seg_queue);
2575 err = -ENOTCONN;
2576 }
2577
2578 if (err)
2579 break;
2580
2581 if (chan->mode == L2CAP_MODE_ERTM)
2582 l2cap_tx(chan, NULL, &seg_queue, L2CAP_EV_DATA_REQUEST);
2583 else
2584 l2cap_streaming_send(chan, &seg_queue);
2585
2586 err = len;
2587
2588 /* If the skbs were not queued for sending, they'll still be in
2589 * seg_queue and need to be purged.
2590 */
2591 __skb_queue_purge(&seg_queue);
2592 break;
2593
2594 default:
2595 BT_DBG("bad state %1.1x", chan->mode);
2596 err = -EBADFD;
2597 }
2598
2599 return err;
2600}
2601EXPORT_SYMBOL_GPL(l2cap_chan_send);
2602
2603static void l2cap_send_srej(struct l2cap_chan *chan, u16 txseq)
2604{
2605 struct l2cap_ctrl control;
2606 u16 seq;
2607
2608 BT_DBG("chan %p, txseq %u", chan, txseq);
2609
2610 memset(&control, 0, sizeof(control));
2611 control.sframe = 1;
2612 control.super = L2CAP_SUPER_SREJ;
2613
2614 for (seq = chan->expected_tx_seq; seq != txseq;
2615 seq = __next_seq(chan, seq)) {
2616 if (!l2cap_ertm_seq_in_queue(&chan->srej_q, seq)) {
2617 control.reqseq = seq;
2618 l2cap_send_sframe(chan, &control);
2619 l2cap_seq_list_append(&chan->srej_list, seq);
2620 }
2621 }
2622
2623 chan->expected_tx_seq = __next_seq(chan, txseq);
2624}
2625
2626static void l2cap_send_srej_tail(struct l2cap_chan *chan)
2627{
2628 struct l2cap_ctrl control;
2629
2630 BT_DBG("chan %p", chan);
2631
2632 if (chan->srej_list.tail == L2CAP_SEQ_LIST_CLEAR)
2633 return;
2634
2635 memset(&control, 0, sizeof(control));
2636 control.sframe = 1;
2637 control.super = L2CAP_SUPER_SREJ;
2638 control.reqseq = chan->srej_list.tail;
2639 l2cap_send_sframe(chan, &control);
2640}
2641
2642static void l2cap_send_srej_list(struct l2cap_chan *chan, u16 txseq)
2643{
2644 struct l2cap_ctrl control;
2645 u16 initial_head;
2646 u16 seq;
2647
2648 BT_DBG("chan %p, txseq %u", chan, txseq);
2649
2650 memset(&control, 0, sizeof(control));
2651 control.sframe = 1;
2652 control.super = L2CAP_SUPER_SREJ;
2653
2654 /* Capture initial list head to allow only one pass through the list. */
2655 initial_head = chan->srej_list.head;
2656
2657 do {
2658 seq = l2cap_seq_list_pop(&chan->srej_list);
2659 if (seq == txseq || seq == L2CAP_SEQ_LIST_CLEAR)
2660 break;
2661
2662 control.reqseq = seq;
2663 l2cap_send_sframe(chan, &control);
2664 l2cap_seq_list_append(&chan->srej_list, seq);
2665 } while (chan->srej_list.head != initial_head);
2666}
2667
2668static void l2cap_process_reqseq(struct l2cap_chan *chan, u16 reqseq)
2669{
2670 struct sk_buff *acked_skb;
2671 u16 ackseq;
2672
2673 BT_DBG("chan %p, reqseq %u", chan, reqseq);
2674
2675 if (chan->unacked_frames == 0 || reqseq == chan->expected_ack_seq)
2676 return;
2677
2678 BT_DBG("expected_ack_seq %u, unacked_frames %u",
2679 chan->expected_ack_seq, chan->unacked_frames);
2680
2681 for (ackseq = chan->expected_ack_seq; ackseq != reqseq;
2682 ackseq = __next_seq(chan, ackseq)) {
2683
2684 acked_skb = l2cap_ertm_seq_in_queue(&chan->tx_q, ackseq);
2685 if (acked_skb) {
2686 skb_unlink(acked_skb, &chan->tx_q);
2687 kfree_skb(acked_skb);
2688 chan->unacked_frames--;
2689 }
2690 }
2691
2692 chan->expected_ack_seq = reqseq;
2693
2694 if (chan->unacked_frames == 0)
2695 __clear_retrans_timer(chan);
2696
2697 BT_DBG("unacked_frames %u", chan->unacked_frames);
2698}
2699
2700static void l2cap_abort_rx_srej_sent(struct l2cap_chan *chan)
2701{
2702 BT_DBG("chan %p", chan);
2703
2704 chan->expected_tx_seq = chan->buffer_seq;
2705 l2cap_seq_list_clear(&chan->srej_list);
2706 skb_queue_purge(&chan->srej_q);
2707 chan->rx_state = L2CAP_RX_STATE_RECV;
2708}
2709
2710static void l2cap_tx_state_xmit(struct l2cap_chan *chan,
2711 struct l2cap_ctrl *control,
2712 struct sk_buff_head *skbs, u8 event)
2713{
2714 BT_DBG("chan %p, control %p, skbs %p, event %d", chan, control, skbs,
2715 event);
2716
2717 switch (event) {
2718 case L2CAP_EV_DATA_REQUEST:
2719 if (chan->tx_send_head == NULL)
2720 chan->tx_send_head = skb_peek(skbs);
2721
2722 skb_queue_splice_tail_init(skbs, &chan->tx_q);
2723 l2cap_ertm_send(chan);
2724 break;
2725 case L2CAP_EV_LOCAL_BUSY_DETECTED:
2726 BT_DBG("Enter LOCAL_BUSY");
2727 set_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2728
2729 if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) {
2730 /* The SREJ_SENT state must be aborted if we are to
2731 * enter the LOCAL_BUSY state.
2732 */
2733 l2cap_abort_rx_srej_sent(chan);
2734 }
2735
2736 l2cap_send_ack(chan);
2737
2738 break;
2739 case L2CAP_EV_LOCAL_BUSY_CLEAR:
2740 BT_DBG("Exit LOCAL_BUSY");
2741 clear_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2742
2743 if (test_bit(CONN_RNR_SENT, &chan->conn_state)) {
2744 struct l2cap_ctrl local_control;
2745
2746 memset(&local_control, 0, sizeof(local_control));
2747 local_control.sframe = 1;
2748 local_control.super = L2CAP_SUPER_RR;
2749 local_control.poll = 1;
2750 local_control.reqseq = chan->buffer_seq;
2751 l2cap_send_sframe(chan, &local_control);
2752
2753 chan->retry_count = 1;
2754 __set_monitor_timer(chan);
2755 chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2756 }
2757 break;
2758 case L2CAP_EV_RECV_REQSEQ_AND_FBIT:
2759 l2cap_process_reqseq(chan, control->reqseq);
2760 break;
2761 case L2CAP_EV_EXPLICIT_POLL:
2762 l2cap_send_rr_or_rnr(chan, 1);
2763 chan->retry_count = 1;
2764 __set_monitor_timer(chan);
2765 __clear_ack_timer(chan);
2766 chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2767 break;
2768 case L2CAP_EV_RETRANS_TO:
2769 l2cap_send_rr_or_rnr(chan, 1);
2770 chan->retry_count = 1;
2771 __set_monitor_timer(chan);
2772 chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2773 break;
2774 case L2CAP_EV_RECV_FBIT:
2775 /* Nothing to process */
2776 break;
2777 default:
2778 break;
2779 }
2780}
2781
2782static void l2cap_tx_state_wait_f(struct l2cap_chan *chan,
2783 struct l2cap_ctrl *control,
2784 struct sk_buff_head *skbs, u8 event)
2785{
2786 BT_DBG("chan %p, control %p, skbs %p, event %d", chan, control, skbs,
2787 event);
2788
2789 switch (event) {
2790 case L2CAP_EV_DATA_REQUEST:
2791 if (chan->tx_send_head == NULL)
2792 chan->tx_send_head = skb_peek(skbs);
2793 /* Queue data, but don't send. */
2794 skb_queue_splice_tail_init(skbs, &chan->tx_q);
2795 break;
2796 case L2CAP_EV_LOCAL_BUSY_DETECTED:
2797 BT_DBG("Enter LOCAL_BUSY");
2798 set_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2799
2800 if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) {
2801 /* The SREJ_SENT state must be aborted if we are to
2802 * enter the LOCAL_BUSY state.
2803 */
2804 l2cap_abort_rx_srej_sent(chan);
2805 }
2806
2807 l2cap_send_ack(chan);
2808
2809 break;
2810 case L2CAP_EV_LOCAL_BUSY_CLEAR:
2811 BT_DBG("Exit LOCAL_BUSY");
2812 clear_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2813
2814 if (test_bit(CONN_RNR_SENT, &chan->conn_state)) {
2815 struct l2cap_ctrl local_control;
2816 memset(&local_control, 0, sizeof(local_control));
2817 local_control.sframe = 1;
2818 local_control.super = L2CAP_SUPER_RR;
2819 local_control.poll = 1;
2820 local_control.reqseq = chan->buffer_seq;
2821 l2cap_send_sframe(chan, &local_control);
2822
2823 chan->retry_count = 1;
2824 __set_monitor_timer(chan);
2825 chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2826 }
2827 break;
2828 case L2CAP_EV_RECV_REQSEQ_AND_FBIT:
2829 l2cap_process_reqseq(chan, control->reqseq);
2830
2831 /* Fall through */
2832
2833 case L2CAP_EV_RECV_FBIT:
2834 if (control && control->final) {
2835 __clear_monitor_timer(chan);
2836 if (chan->unacked_frames > 0)
2837 __set_retrans_timer(chan);
2838 chan->retry_count = 0;
2839 chan->tx_state = L2CAP_TX_STATE_XMIT;
2840 BT_DBG("recv fbit tx_state 0x2.2%x", chan->tx_state);
2841 }
2842 break;
2843 case L2CAP_EV_EXPLICIT_POLL:
2844 /* Ignore */
2845 break;
2846 case L2CAP_EV_MONITOR_TO:
2847 if (chan->max_tx == 0 || chan->retry_count < chan->max_tx) {
2848 l2cap_send_rr_or_rnr(chan, 1);
2849 __set_monitor_timer(chan);
2850 chan->retry_count++;
2851 } else {
2852 l2cap_send_disconn_req(chan, ECONNABORTED);
2853 }
2854 break;
2855 default:
2856 break;
2857 }
2858}
2859
2860static void l2cap_tx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
2861 struct sk_buff_head *skbs, u8 event)
2862{
2863 BT_DBG("chan %p, control %p, skbs %p, event %d, state %d",
2864 chan, control, skbs, event, chan->tx_state);
2865
2866 switch (chan->tx_state) {
2867 case L2CAP_TX_STATE_XMIT:
2868 l2cap_tx_state_xmit(chan, control, skbs, event);
2869 break;
2870 case L2CAP_TX_STATE_WAIT_F:
2871 l2cap_tx_state_wait_f(chan, control, skbs, event);
2872 break;
2873 default:
2874 /* Ignore event */
2875 break;
2876 }
2877}
2878
2879static void l2cap_pass_to_tx(struct l2cap_chan *chan,
2880 struct l2cap_ctrl *control)
2881{
2882 BT_DBG("chan %p, control %p", chan, control);
2883 l2cap_tx(chan, control, NULL, L2CAP_EV_RECV_REQSEQ_AND_FBIT);
2884}
2885
2886static void l2cap_pass_to_tx_fbit(struct l2cap_chan *chan,
2887 struct l2cap_ctrl *control)
2888{
2889 BT_DBG("chan %p, control %p", chan, control);
2890 l2cap_tx(chan, control, NULL, L2CAP_EV_RECV_FBIT);
2891}
2892
2893/* Copy frame to all raw sockets on that connection */
2894static void l2cap_raw_recv(struct l2cap_conn *conn, struct sk_buff *skb)
2895{
2896 struct sk_buff *nskb;
2897 struct l2cap_chan *chan;
2898
2899 BT_DBG("conn %p", conn);
2900
2901 mutex_lock(&conn->chan_lock);
2902
2903 list_for_each_entry(chan, &conn->chan_l, list) {
2904 if (chan->chan_type != L2CAP_CHAN_RAW)
2905 continue;
2906
2907 /* Don't send frame to the channel it came from */
2908 if (bt_cb(skb)->l2cap.chan == chan)
2909 continue;
2910
2911 nskb = skb_clone(skb, GFP_KERNEL);
2912 if (!nskb)
2913 continue;
2914 if (chan->ops->recv(chan, nskb))
2915 kfree_skb(nskb);
2916 }
2917
2918 mutex_unlock(&conn->chan_lock);
2919}
2920
2921/* ---- L2CAP signalling commands ---- */
2922static struct sk_buff *l2cap_build_cmd(struct l2cap_conn *conn, u8 code,
2923 u8 ident, u16 dlen, void *data)
2924{
2925 struct sk_buff *skb, **frag;
2926 struct l2cap_cmd_hdr *cmd;
2927 struct l2cap_hdr *lh;
2928 int len, count;
2929
2930 BT_DBG("conn %p, code 0x%2.2x, ident 0x%2.2x, len %u",
2931 conn, code, ident, dlen);
2932
2933 if (conn->mtu < L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE)
2934 return NULL;
2935
2936 len = L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE + dlen;
2937 count = min_t(unsigned int, conn->mtu, len);
2938
2939 skb = bt_skb_alloc(count, GFP_KERNEL);
2940 if (!skb)
2941 return NULL;
2942
2943 lh = skb_put(skb, L2CAP_HDR_SIZE);
2944 lh->len = cpu_to_le16(L2CAP_CMD_HDR_SIZE + dlen);
2945
2946 if (conn->hcon->type == LE_LINK)
2947 lh->cid = cpu_to_le16(L2CAP_CID_LE_SIGNALING);
2948 else
2949 lh->cid = cpu_to_le16(L2CAP_CID_SIGNALING);
2950
2951 cmd = skb_put(skb, L2CAP_CMD_HDR_SIZE);
2952 cmd->code = code;
2953 cmd->ident = ident;
2954 cmd->len = cpu_to_le16(dlen);
2955
2956 if (dlen) {
2957 count -= L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE;
2958 skb_put_data(skb, data, count);
2959 data += count;
2960 }
2961
2962 len -= skb->len;
2963
2964 /* Continuation fragments (no L2CAP header) */
2965 frag = &skb_shinfo(skb)->frag_list;
2966 while (len) {
2967 count = min_t(unsigned int, conn->mtu, len);
2968
2969 *frag = bt_skb_alloc(count, GFP_KERNEL);
2970 if (!*frag)
2971 goto fail;
2972
2973 skb_put_data(*frag, data, count);
2974
2975 len -= count;
2976 data += count;
2977
2978 frag = &(*frag)->next;
2979 }
2980
2981 return skb;
2982
2983fail:
2984 kfree_skb(skb);
2985 return NULL;
2986}
2987
2988static inline int l2cap_get_conf_opt(void **ptr, int *type, int *olen,
2989 unsigned long *val)
2990{
2991 struct l2cap_conf_opt *opt = *ptr;
2992 int len;
2993
2994 len = L2CAP_CONF_OPT_SIZE + opt->len;
2995 *ptr += len;
2996
2997 *type = opt->type;
2998 *olen = opt->len;
2999
3000 switch (opt->len) {
3001 case 1:
3002 *val = *((u8 *) opt->val);
3003 break;
3004
3005 case 2:
3006 *val = get_unaligned_le16(opt->val);
3007 break;
3008
3009 case 4:
3010 *val = get_unaligned_le32(opt->val);
3011 break;
3012
3013 default:
3014 *val = (unsigned long) opt->val;
3015 break;
3016 }
3017
3018 BT_DBG("type 0x%2.2x len %u val 0x%lx", *type, opt->len, *val);
3019 return len;
3020}
3021
3022static void l2cap_add_conf_opt(void **ptr, u8 type, u8 len, unsigned long val, size_t size)
3023{
3024 struct l2cap_conf_opt *opt = *ptr;
3025
3026 BT_DBG("type 0x%2.2x len %u val 0x%lx", type, len, val);
3027
3028 if (size < L2CAP_CONF_OPT_SIZE + len)
3029 return;
3030
3031 opt->type = type;
3032 opt->len = len;
3033
3034 switch (len) {
3035 case 1:
3036 *((u8 *) opt->val) = val;
3037 break;
3038
3039 case 2:
3040 put_unaligned_le16(val, opt->val);
3041 break;
3042
3043 case 4:
3044 put_unaligned_le32(val, opt->val);
3045 break;
3046
3047 default:
3048 memcpy(opt->val, (void *) val, len);
3049 break;
3050 }
3051
3052 *ptr += L2CAP_CONF_OPT_SIZE + len;
3053}
3054
3055static void l2cap_add_opt_efs(void **ptr, struct l2cap_chan *chan, size_t size)
3056{
3057 struct l2cap_conf_efs efs;
3058
3059 switch (chan->mode) {
3060 case L2CAP_MODE_ERTM:
3061 efs.id = chan->local_id;
3062 efs.stype = chan->local_stype;
3063 efs.msdu = cpu_to_le16(chan->local_msdu);
3064 efs.sdu_itime = cpu_to_le32(chan->local_sdu_itime);
3065 efs.acc_lat = cpu_to_le32(L2CAP_DEFAULT_ACC_LAT);
3066 efs.flush_to = cpu_to_le32(L2CAP_EFS_DEFAULT_FLUSH_TO);
3067 break;
3068
3069 case L2CAP_MODE_STREAMING:
3070 efs.id = 1;
3071 efs.stype = L2CAP_SERV_BESTEFFORT;
3072 efs.msdu = cpu_to_le16(chan->local_msdu);
3073 efs.sdu_itime = cpu_to_le32(chan->local_sdu_itime);
3074 efs.acc_lat = 0;
3075 efs.flush_to = 0;
3076 break;
3077
3078 default:
3079 return;
3080 }
3081
3082 l2cap_add_conf_opt(ptr, L2CAP_CONF_EFS, sizeof(efs),
3083 (unsigned long) &efs, size);
3084}
3085
3086static void l2cap_ack_timeout(struct work_struct *work)
3087{
3088 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
3089 ack_timer.work);
3090 u16 frames_to_ack;
3091
3092 BT_DBG("chan %p", chan);
3093
3094 l2cap_chan_lock(chan);
3095
3096 frames_to_ack = __seq_offset(chan, chan->buffer_seq,
3097 chan->last_acked_seq);
3098
3099 if (frames_to_ack)
3100 l2cap_send_rr_or_rnr(chan, 0);
3101
3102 l2cap_chan_unlock(chan);
3103 l2cap_chan_put(chan);
3104}
3105
3106int l2cap_ertm_init(struct l2cap_chan *chan)
3107{
3108 int err;
3109
3110 chan->next_tx_seq = 0;
3111 chan->expected_tx_seq = 0;
3112 chan->expected_ack_seq = 0;
3113 chan->unacked_frames = 0;
3114 chan->buffer_seq = 0;
3115 chan->frames_sent = 0;
3116 chan->last_acked_seq = 0;
3117 chan->sdu = NULL;
3118 chan->sdu_last_frag = NULL;
3119 chan->sdu_len = 0;
3120
3121 skb_queue_head_init(&chan->tx_q);
3122
3123 chan->local_amp_id = AMP_ID_BREDR;
3124 chan->move_id = AMP_ID_BREDR;
3125 chan->move_state = L2CAP_MOVE_STABLE;
3126 chan->move_role = L2CAP_MOVE_ROLE_NONE;
3127
3128 if (chan->mode != L2CAP_MODE_ERTM)
3129 return 0;
3130
3131 chan->rx_state = L2CAP_RX_STATE_RECV;
3132 chan->tx_state = L2CAP_TX_STATE_XMIT;
3133
3134 INIT_DELAYED_WORK(&chan->retrans_timer, l2cap_retrans_timeout);
3135 INIT_DELAYED_WORK(&chan->monitor_timer, l2cap_monitor_timeout);
3136 INIT_DELAYED_WORK(&chan->ack_timer, l2cap_ack_timeout);
3137
3138 skb_queue_head_init(&chan->srej_q);
3139
3140 err = l2cap_seq_list_init(&chan->srej_list, chan->tx_win);
3141 if (err < 0)
3142 return err;
3143
3144 err = l2cap_seq_list_init(&chan->retrans_list, chan->remote_tx_win);
3145 if (err < 0)
3146 l2cap_seq_list_free(&chan->srej_list);
3147
3148 return err;
3149}
3150
3151static inline __u8 l2cap_select_mode(__u8 mode, __u16 remote_feat_mask)
3152{
3153 switch (mode) {
3154 case L2CAP_MODE_STREAMING:
3155 case L2CAP_MODE_ERTM:
3156 if (l2cap_mode_supported(mode, remote_feat_mask))
3157 return mode;
3158 /* fall through */
3159 default:
3160 return L2CAP_MODE_BASIC;
3161 }
3162}
3163
3164static inline bool __l2cap_ews_supported(struct l2cap_conn *conn)
3165{
3166 return ((conn->local_fixed_chan & L2CAP_FC_A2MP) &&
3167 (conn->feat_mask & L2CAP_FEAT_EXT_WINDOW));
3168}
3169
3170static inline bool __l2cap_efs_supported(struct l2cap_conn *conn)
3171{
3172 return ((conn->local_fixed_chan & L2CAP_FC_A2MP) &&
3173 (conn->feat_mask & L2CAP_FEAT_EXT_FLOW));
3174}
3175
3176static void __l2cap_set_ertm_timeouts(struct l2cap_chan *chan,
3177 struct l2cap_conf_rfc *rfc)
3178{
3179 if (chan->local_amp_id != AMP_ID_BREDR && chan->hs_hcon) {
3180 u64 ertm_to = chan->hs_hcon->hdev->amp_be_flush_to;
3181
3182 /* Class 1 devices have must have ERTM timeouts
3183 * exceeding the Link Supervision Timeout. The
3184 * default Link Supervision Timeout for AMP
3185 * controllers is 10 seconds.
3186 *
3187 * Class 1 devices use 0xffffffff for their
3188 * best-effort flush timeout, so the clamping logic
3189 * will result in a timeout that meets the above
3190 * requirement. ERTM timeouts are 16-bit values, so
3191 * the maximum timeout is 65.535 seconds.
3192 */
3193
3194 /* Convert timeout to milliseconds and round */
3195 ertm_to = DIV_ROUND_UP_ULL(ertm_to, 1000);
3196
3197 /* This is the recommended formula for class 2 devices
3198 * that start ERTM timers when packets are sent to the
3199 * controller.
3200 */
3201 ertm_to = 3 * ertm_to + 500;
3202
3203 if (ertm_to > 0xffff)
3204 ertm_to = 0xffff;
3205
3206 rfc->retrans_timeout = cpu_to_le16((u16) ertm_to);
3207 rfc->monitor_timeout = rfc->retrans_timeout;
3208 } else {
3209 rfc->retrans_timeout = cpu_to_le16(L2CAP_DEFAULT_RETRANS_TO);
3210 rfc->monitor_timeout = cpu_to_le16(L2CAP_DEFAULT_MONITOR_TO);
3211 }
3212}
3213
3214static inline void l2cap_txwin_setup(struct l2cap_chan *chan)
3215{
3216 if (chan->tx_win > L2CAP_DEFAULT_TX_WINDOW &&
3217 __l2cap_ews_supported(chan->conn)) {
3218 /* use extended control field */
3219 set_bit(FLAG_EXT_CTRL, &chan->flags);
3220 chan->tx_win_max = L2CAP_DEFAULT_EXT_WINDOW;
3221 } else {
3222 chan->tx_win = min_t(u16, chan->tx_win,
3223 L2CAP_DEFAULT_TX_WINDOW);
3224 chan->tx_win_max = L2CAP_DEFAULT_TX_WINDOW;
3225 }
3226 chan->ack_win = chan->tx_win;
3227}
3228
3229static int l2cap_build_conf_req(struct l2cap_chan *chan, void *data, size_t data_size)
3230{
3231 struct l2cap_conf_req *req = data;
3232 struct l2cap_conf_rfc rfc = { .mode = chan->mode };
3233 void *ptr = req->data;
3234 void *endptr = data + data_size;
3235 u16 size;
3236
3237 BT_DBG("chan %p", chan);
3238
3239 if (chan->num_conf_req || chan->num_conf_rsp)
3240 goto done;
3241
3242 switch (chan->mode) {
3243 case L2CAP_MODE_STREAMING:
3244 case L2CAP_MODE_ERTM:
3245 if (test_bit(CONF_STATE2_DEVICE, &chan->conf_state))
3246 break;
3247
3248 if (__l2cap_efs_supported(chan->conn))
3249 set_bit(FLAG_EFS_ENABLE, &chan->flags);
3250
3251 /* fall through */
3252 default:
3253 chan->mode = l2cap_select_mode(rfc.mode, chan->conn->feat_mask);
3254 break;
3255 }
3256
3257done:
3258 if (chan->imtu != L2CAP_DEFAULT_MTU)
3259 l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->imtu, endptr - ptr);
3260
3261 switch (chan->mode) {
3262 case L2CAP_MODE_BASIC:
3263 if (disable_ertm)
3264 break;
3265
3266 if (!(chan->conn->feat_mask & L2CAP_FEAT_ERTM) &&
3267 !(chan->conn->feat_mask & L2CAP_FEAT_STREAMING))
3268 break;
3269
3270 rfc.mode = L2CAP_MODE_BASIC;
3271 rfc.txwin_size = 0;
3272 rfc.max_transmit = 0;
3273 rfc.retrans_timeout = 0;
3274 rfc.monitor_timeout = 0;
3275 rfc.max_pdu_size = 0;
3276
3277 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3278 (unsigned long) &rfc, endptr - ptr);
3279 break;
3280
3281 case L2CAP_MODE_ERTM:
3282 rfc.mode = L2CAP_MODE_ERTM;
3283 rfc.max_transmit = chan->max_tx;
3284
3285 __l2cap_set_ertm_timeouts(chan, &rfc);
3286
3287 size = min_t(u16, L2CAP_DEFAULT_MAX_PDU_SIZE, chan->conn->mtu -
3288 L2CAP_EXT_HDR_SIZE - L2CAP_SDULEN_SIZE -
3289 L2CAP_FCS_SIZE);
3290 rfc.max_pdu_size = cpu_to_le16(size);
3291
3292 l2cap_txwin_setup(chan);
3293
3294 rfc.txwin_size = min_t(u16, chan->tx_win,
3295 L2CAP_DEFAULT_TX_WINDOW);
3296
3297 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3298 (unsigned long) &rfc, endptr - ptr);
3299
3300 if (test_bit(FLAG_EFS_ENABLE, &chan->flags))
3301 l2cap_add_opt_efs(&ptr, chan, endptr - ptr);
3302
3303 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
3304 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EWS, 2,
3305 chan->tx_win, endptr - ptr);
3306
3307 if (chan->conn->feat_mask & L2CAP_FEAT_FCS)
3308 if (chan->fcs == L2CAP_FCS_NONE ||
3309 test_bit(CONF_RECV_NO_FCS, &chan->conf_state)) {
3310 chan->fcs = L2CAP_FCS_NONE;
3311 l2cap_add_conf_opt(&ptr, L2CAP_CONF_FCS, 1,
3312 chan->fcs, endptr - ptr);
3313 }
3314 break;
3315
3316 case L2CAP_MODE_STREAMING:
3317 l2cap_txwin_setup(chan);
3318 rfc.mode = L2CAP_MODE_STREAMING;
3319 rfc.txwin_size = 0;
3320 rfc.max_transmit = 0;
3321 rfc.retrans_timeout = 0;
3322 rfc.monitor_timeout = 0;
3323
3324 size = min_t(u16, L2CAP_DEFAULT_MAX_PDU_SIZE, chan->conn->mtu -
3325 L2CAP_EXT_HDR_SIZE - L2CAP_SDULEN_SIZE -
3326 L2CAP_FCS_SIZE);
3327 rfc.max_pdu_size = cpu_to_le16(size);
3328
3329 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3330 (unsigned long) &rfc, endptr - ptr);
3331
3332 if (test_bit(FLAG_EFS_ENABLE, &chan->flags))
3333 l2cap_add_opt_efs(&ptr, chan, endptr - ptr);
3334
3335 if (chan->conn->feat_mask & L2CAP_FEAT_FCS)
3336 if (chan->fcs == L2CAP_FCS_NONE ||
3337 test_bit(CONF_RECV_NO_FCS, &chan->conf_state)) {
3338 chan->fcs = L2CAP_FCS_NONE;
3339 l2cap_add_conf_opt(&ptr, L2CAP_CONF_FCS, 1,
3340 chan->fcs, endptr - ptr);
3341 }
3342 break;
3343 }
3344
3345 req->dcid = cpu_to_le16(chan->dcid);
3346 req->flags = cpu_to_le16(0);
3347
3348 return ptr - data;
3349}
3350
3351static int l2cap_parse_conf_req(struct l2cap_chan *chan, void *data, size_t data_size)
3352{
3353 struct l2cap_conf_rsp *rsp = data;
3354 void *ptr = rsp->data;
3355 void *endptr = data + data_size;
3356 void *req = chan->conf_req;
3357 int len = chan->conf_len;
3358 int type, hint, olen;
3359 unsigned long val;
3360 struct l2cap_conf_rfc rfc = { .mode = L2CAP_MODE_BASIC };
3361 struct l2cap_conf_efs efs;
3362 u8 remote_efs = 0;
3363 u16 mtu = L2CAP_DEFAULT_MTU;
3364 u16 result = L2CAP_CONF_SUCCESS;
3365 u16 size;
3366
3367 BT_DBG("chan %p", chan);
3368
3369 while (len >= L2CAP_CONF_OPT_SIZE) {
3370 len -= l2cap_get_conf_opt(&req, &type, &olen, &val);
3371 if (len < 0)
3372 break;
3373
3374 hint = type & L2CAP_CONF_HINT;
3375 type &= L2CAP_CONF_MASK;
3376
3377 switch (type) {
3378 case L2CAP_CONF_MTU:
3379 if (olen != 2)
3380 break;
3381 mtu = val;
3382 break;
3383
3384 case L2CAP_CONF_FLUSH_TO:
3385 if (olen != 2)
3386 break;
3387 chan->flush_to = val;
3388 break;
3389
3390 case L2CAP_CONF_QOS:
3391 break;
3392
3393 case L2CAP_CONF_RFC:
3394 if (olen != sizeof(rfc))
3395 break;
3396 memcpy(&rfc, (void *) val, olen);
3397 break;
3398
3399 case L2CAP_CONF_FCS:
3400 if (olen != 1)
3401 break;
3402 if (val == L2CAP_FCS_NONE)
3403 set_bit(CONF_RECV_NO_FCS, &chan->conf_state);
3404 break;
3405
3406 case L2CAP_CONF_EFS:
3407 if (olen != sizeof(efs))
3408 break;
3409 remote_efs = 1;
3410 memcpy(&efs, (void *) val, olen);
3411 break;
3412
3413 case L2CAP_CONF_EWS:
3414 if (olen != 2)
3415 break;
3416 if (!(chan->conn->local_fixed_chan & L2CAP_FC_A2MP))
3417 return -ECONNREFUSED;
3418 set_bit(FLAG_EXT_CTRL, &chan->flags);
3419 set_bit(CONF_EWS_RECV, &chan->conf_state);
3420 chan->tx_win_max = L2CAP_DEFAULT_EXT_WINDOW;
3421 chan->remote_tx_win = val;
3422 break;
3423
3424 default:
3425 if (hint)
3426 break;
3427 result = L2CAP_CONF_UNKNOWN;
3428 *((u8 *) ptr++) = type;
3429 break;
3430 }
3431 }
3432
3433 if (chan->num_conf_rsp || chan->num_conf_req > 1)
3434 goto done;
3435
3436 switch (chan->mode) {
3437 case L2CAP_MODE_STREAMING:
3438 case L2CAP_MODE_ERTM:
3439 if (!test_bit(CONF_STATE2_DEVICE, &chan->conf_state)) {
3440 chan->mode = l2cap_select_mode(rfc.mode,
3441 chan->conn->feat_mask);
3442 break;
3443 }
3444
3445 if (remote_efs) {
3446 if (__l2cap_efs_supported(chan->conn))
3447 set_bit(FLAG_EFS_ENABLE, &chan->flags);
3448 else
3449 return -ECONNREFUSED;
3450 }
3451
3452 if (chan->mode != rfc.mode)
3453 return -ECONNREFUSED;
3454
3455 break;
3456 }
3457
3458done:
3459 if (chan->mode != rfc.mode) {
3460 result = L2CAP_CONF_UNACCEPT;
3461 rfc.mode = chan->mode;
3462
3463 if (chan->num_conf_rsp == 1)
3464 return -ECONNREFUSED;
3465
3466 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3467 (unsigned long) &rfc, endptr - ptr);
3468 }
3469
3470 if (result == L2CAP_CONF_SUCCESS) {
3471 /* Configure output options and let the other side know
3472 * which ones we don't like. */
3473
3474 if (mtu < L2CAP_DEFAULT_MIN_MTU)
3475 result = L2CAP_CONF_UNACCEPT;
3476 else {
3477 chan->omtu = mtu;
3478 set_bit(CONF_MTU_DONE, &chan->conf_state);
3479 }
3480 l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->omtu, endptr - ptr);
3481
3482 if (remote_efs) {
3483 if (chan->local_stype != L2CAP_SERV_NOTRAFIC &&
3484 efs.stype != L2CAP_SERV_NOTRAFIC &&
3485 efs.stype != chan->local_stype) {
3486
3487 result = L2CAP_CONF_UNACCEPT;
3488
3489 if (chan->num_conf_req >= 1)
3490 return -ECONNREFUSED;
3491
3492 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS,
3493 sizeof(efs),
3494 (unsigned long) &efs, endptr - ptr);
3495 } else {
3496 /* Send PENDING Conf Rsp */
3497 result = L2CAP_CONF_PENDING;
3498 set_bit(CONF_LOC_CONF_PEND, &chan->conf_state);
3499 }
3500 }
3501
3502 switch (rfc.mode) {
3503 case L2CAP_MODE_BASIC:
3504 chan->fcs = L2CAP_FCS_NONE;
3505 set_bit(CONF_MODE_DONE, &chan->conf_state);
3506 break;
3507
3508 case L2CAP_MODE_ERTM:
3509 if (!test_bit(CONF_EWS_RECV, &chan->conf_state))
3510 chan->remote_tx_win = rfc.txwin_size;
3511 else
3512 rfc.txwin_size = L2CAP_DEFAULT_TX_WINDOW;
3513
3514 chan->remote_max_tx = rfc.max_transmit;
3515
3516 size = min_t(u16, le16_to_cpu(rfc.max_pdu_size),
3517 chan->conn->mtu - L2CAP_EXT_HDR_SIZE -
3518 L2CAP_SDULEN_SIZE - L2CAP_FCS_SIZE);
3519 rfc.max_pdu_size = cpu_to_le16(size);
3520 chan->remote_mps = size;
3521
3522 __l2cap_set_ertm_timeouts(chan, &rfc);
3523
3524 set_bit(CONF_MODE_DONE, &chan->conf_state);
3525
3526 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC,
3527 sizeof(rfc), (unsigned long) &rfc, endptr - ptr);
3528
3529 if (test_bit(FLAG_EFS_ENABLE, &chan->flags)) {
3530 chan->remote_id = efs.id;
3531 chan->remote_stype = efs.stype;
3532 chan->remote_msdu = le16_to_cpu(efs.msdu);
3533 chan->remote_flush_to =
3534 le32_to_cpu(efs.flush_to);
3535 chan->remote_acc_lat =
3536 le32_to_cpu(efs.acc_lat);
3537 chan->remote_sdu_itime =
3538 le32_to_cpu(efs.sdu_itime);
3539 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS,
3540 sizeof(efs),
3541 (unsigned long) &efs, endptr - ptr);
3542 }
3543 break;
3544
3545 case L2CAP_MODE_STREAMING:
3546 size = min_t(u16, le16_to_cpu(rfc.max_pdu_size),
3547 chan->conn->mtu - L2CAP_EXT_HDR_SIZE -
3548 L2CAP_SDULEN_SIZE - L2CAP_FCS_SIZE);
3549 rfc.max_pdu_size = cpu_to_le16(size);
3550 chan->remote_mps = size;
3551
3552 set_bit(CONF_MODE_DONE, &chan->conf_state);
3553
3554 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3555 (unsigned long) &rfc, endptr - ptr);
3556
3557 break;
3558
3559 default:
3560 result = L2CAP_CONF_UNACCEPT;
3561
3562 memset(&rfc, 0, sizeof(rfc));
3563 rfc.mode = chan->mode;
3564 }
3565
3566 if (result == L2CAP_CONF_SUCCESS)
3567 set_bit(CONF_OUTPUT_DONE, &chan->conf_state);
3568 }
3569 rsp->scid = cpu_to_le16(chan->dcid);
3570 rsp->result = cpu_to_le16(result);
3571 rsp->flags = cpu_to_le16(0);
3572
3573 return ptr - data;
3574}
3575
3576static int l2cap_parse_conf_rsp(struct l2cap_chan *chan, void *rsp, int len,
3577 void *data, size_t size, u16 *result)
3578{
3579 struct l2cap_conf_req *req = data;
3580 void *ptr = req->data;
3581 void *endptr = data + size;
3582 int type, olen;
3583 unsigned long val;
3584 struct l2cap_conf_rfc rfc = { .mode = L2CAP_MODE_BASIC };
3585 struct l2cap_conf_efs efs;
3586
3587 BT_DBG("chan %p, rsp %p, len %d, req %p", chan, rsp, len, data);
3588
3589 while (len >= L2CAP_CONF_OPT_SIZE) {
3590 len -= l2cap_get_conf_opt(&rsp, &type, &olen, &val);
3591 if (len < 0)
3592 break;
3593
3594 switch (type) {
3595 case L2CAP_CONF_MTU:
3596 if (olen != 2)
3597 break;
3598 if (val < L2CAP_DEFAULT_MIN_MTU) {
3599 *result = L2CAP_CONF_UNACCEPT;
3600 chan->imtu = L2CAP_DEFAULT_MIN_MTU;
3601 } else
3602 chan->imtu = val;
3603 l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->imtu,
3604 endptr - ptr);
3605 break;
3606
3607 case L2CAP_CONF_FLUSH_TO:
3608 if (olen != 2)
3609 break;
3610 chan->flush_to = val;
3611 l2cap_add_conf_opt(&ptr, L2CAP_CONF_FLUSH_TO, 2,
3612 chan->flush_to, endptr - ptr);
3613 break;
3614
3615 case L2CAP_CONF_RFC:
3616 if (olen != sizeof(rfc))
3617 break;
3618 memcpy(&rfc, (void *)val, olen);
3619 if (test_bit(CONF_STATE2_DEVICE, &chan->conf_state) &&
3620 rfc.mode != chan->mode)
3621 return -ECONNREFUSED;
3622 chan->fcs = 0;
3623 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3624 (unsigned long) &rfc, endptr - ptr);
3625 break;
3626
3627 case L2CAP_CONF_EWS:
3628 if (olen != 2)
3629 break;
3630 chan->ack_win = min_t(u16, val, chan->ack_win);
3631 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EWS, 2,
3632 chan->tx_win, endptr - ptr);
3633 break;
3634
3635 case L2CAP_CONF_EFS:
3636 if (olen != sizeof(efs))
3637 break;
3638 memcpy(&efs, (void *)val, olen);
3639 if (chan->local_stype != L2CAP_SERV_NOTRAFIC &&
3640 efs.stype != L2CAP_SERV_NOTRAFIC &&
3641 efs.stype != chan->local_stype)
3642 return -ECONNREFUSED;
3643 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS, sizeof(efs),
3644 (unsigned long) &efs, endptr - ptr);
3645 break;
3646
3647 case L2CAP_CONF_FCS:
3648 if (olen != 1)
3649 break;
3650 if (*result == L2CAP_CONF_PENDING)
3651 if (val == L2CAP_FCS_NONE)
3652 set_bit(CONF_RECV_NO_FCS,
3653 &chan->conf_state);
3654 break;
3655 }
3656 }
3657
3658 if (chan->mode == L2CAP_MODE_BASIC && chan->mode != rfc.mode)
3659 return -ECONNREFUSED;
3660
3661 chan->mode = rfc.mode;
3662
3663 if (*result == L2CAP_CONF_SUCCESS || *result == L2CAP_CONF_PENDING) {
3664 switch (rfc.mode) {
3665 case L2CAP_MODE_ERTM:
3666 chan->retrans_timeout = le16_to_cpu(rfc.retrans_timeout);
3667 chan->monitor_timeout = le16_to_cpu(rfc.monitor_timeout);
3668 chan->mps = le16_to_cpu(rfc.max_pdu_size);
3669 if (!test_bit(FLAG_EXT_CTRL, &chan->flags))
3670 chan->ack_win = min_t(u16, chan->ack_win,
3671 rfc.txwin_size);
3672
3673 if (test_bit(FLAG_EFS_ENABLE, &chan->flags)) {
3674 chan->local_msdu = le16_to_cpu(efs.msdu);
3675 chan->local_sdu_itime =
3676 le32_to_cpu(efs.sdu_itime);
3677 chan->local_acc_lat = le32_to_cpu(efs.acc_lat);
3678 chan->local_flush_to =
3679 le32_to_cpu(efs.flush_to);
3680 }
3681 break;
3682
3683 case L2CAP_MODE_STREAMING:
3684 chan->mps = le16_to_cpu(rfc.max_pdu_size);
3685 }
3686 }
3687
3688 req->dcid = cpu_to_le16(chan->dcid);
3689 req->flags = cpu_to_le16(0);
3690
3691 return ptr - data;
3692}
3693
3694static int l2cap_build_conf_rsp(struct l2cap_chan *chan, void *data,
3695 u16 result, u16 flags)
3696{
3697 struct l2cap_conf_rsp *rsp = data;
3698 void *ptr = rsp->data;
3699
3700 BT_DBG("chan %p", chan);
3701
3702 rsp->scid = cpu_to_le16(chan->dcid);
3703 rsp->result = cpu_to_le16(result);
3704 rsp->flags = cpu_to_le16(flags);
3705
3706 return ptr - data;
3707}
3708
3709void __l2cap_le_connect_rsp_defer(struct l2cap_chan *chan)
3710{
3711 struct l2cap_le_conn_rsp rsp;
3712 struct l2cap_conn *conn = chan->conn;
3713
3714 BT_DBG("chan %p", chan);
3715
3716 rsp.dcid = cpu_to_le16(chan->scid);
3717 rsp.mtu = cpu_to_le16(chan->imtu);
3718 rsp.mps = cpu_to_le16(chan->mps);
3719 rsp.credits = cpu_to_le16(chan->rx_credits);
3720 rsp.result = cpu_to_le16(L2CAP_CR_LE_SUCCESS);
3721
3722 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CONN_RSP, sizeof(rsp),
3723 &rsp);
3724}
3725
3726void __l2cap_connect_rsp_defer(struct l2cap_chan *chan)
3727{
3728 struct l2cap_conn_rsp rsp;
3729 struct l2cap_conn *conn = chan->conn;
3730 u8 buf[128];
3731 u8 rsp_code;
3732
3733 rsp.scid = cpu_to_le16(chan->dcid);
3734 rsp.dcid = cpu_to_le16(chan->scid);
3735 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
3736 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
3737
3738 if (chan->hs_hcon)
3739 rsp_code = L2CAP_CREATE_CHAN_RSP;
3740 else
3741 rsp_code = L2CAP_CONN_RSP;
3742
3743 BT_DBG("chan %p rsp_code %u", chan, rsp_code);
3744
3745 l2cap_send_cmd(conn, chan->ident, rsp_code, sizeof(rsp), &rsp);
3746
3747 if (test_and_set_bit(CONF_REQ_SENT, &chan->conf_state))
3748 return;
3749
3750 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
3751 l2cap_build_conf_req(chan, buf, sizeof(buf)), buf);
3752 chan->num_conf_req++;
3753}
3754
3755static void l2cap_conf_rfc_get(struct l2cap_chan *chan, void *rsp, int len)
3756{
3757 int type, olen;
3758 unsigned long val;
3759 /* Use sane default values in case a misbehaving remote device
3760 * did not send an RFC or extended window size option.
3761 */
3762 u16 txwin_ext = chan->ack_win;
3763 struct l2cap_conf_rfc rfc = {
3764 .mode = chan->mode,
3765 .retrans_timeout = cpu_to_le16(L2CAP_DEFAULT_RETRANS_TO),
3766 .monitor_timeout = cpu_to_le16(L2CAP_DEFAULT_MONITOR_TO),
3767 .max_pdu_size = cpu_to_le16(chan->imtu),
3768 .txwin_size = min_t(u16, chan->ack_win, L2CAP_DEFAULT_TX_WINDOW),
3769 };
3770
3771 BT_DBG("chan %p, rsp %p, len %d", chan, rsp, len);
3772
3773 if ((chan->mode != L2CAP_MODE_ERTM) && (chan->mode != L2CAP_MODE_STREAMING))
3774 return;
3775
3776 while (len >= L2CAP_CONF_OPT_SIZE) {
3777 len -= l2cap_get_conf_opt(&rsp, &type, &olen, &val);
3778 if (len < 0)
3779 break;
3780
3781 switch (type) {
3782 case L2CAP_CONF_RFC:
3783 if (olen != sizeof(rfc))
3784 break;
3785 memcpy(&rfc, (void *)val, olen);
3786 break;
3787 case L2CAP_CONF_EWS:
3788 if (olen != 2)
3789 break;
3790 txwin_ext = val;
3791 break;
3792 }
3793 }
3794
3795 switch (rfc.mode) {
3796 case L2CAP_MODE_ERTM:
3797 chan->retrans_timeout = le16_to_cpu(rfc.retrans_timeout);
3798 chan->monitor_timeout = le16_to_cpu(rfc.monitor_timeout);
3799 chan->mps = le16_to_cpu(rfc.max_pdu_size);
3800 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
3801 chan->ack_win = min_t(u16, chan->ack_win, txwin_ext);
3802 else
3803 chan->ack_win = min_t(u16, chan->ack_win,
3804 rfc.txwin_size);
3805 break;
3806 case L2CAP_MODE_STREAMING:
3807 chan->mps = le16_to_cpu(rfc.max_pdu_size);
3808 }
3809}
3810
3811static inline int l2cap_command_rej(struct l2cap_conn *conn,
3812 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
3813 u8 *data)
3814{
3815 struct l2cap_cmd_rej_unk *rej = (struct l2cap_cmd_rej_unk *) data;
3816
3817 if (cmd_len < sizeof(*rej))
3818 return -EPROTO;
3819
3820 if (rej->reason != L2CAP_REJ_NOT_UNDERSTOOD)
3821 return 0;
3822
3823 if ((conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT) &&
3824 cmd->ident == conn->info_ident) {
3825 cancel_delayed_work(&conn->info_timer);
3826
3827 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
3828 conn->info_ident = 0;
3829
3830 l2cap_conn_start(conn);
3831 }
3832
3833 return 0;
3834}
3835
3836static struct l2cap_chan *l2cap_connect(struct l2cap_conn *conn,
3837 struct l2cap_cmd_hdr *cmd,
3838 u8 *data, u8 rsp_code, u8 amp_id)
3839{
3840 struct l2cap_conn_req *req = (struct l2cap_conn_req *) data;
3841 struct l2cap_conn_rsp rsp;
3842 struct l2cap_chan *chan = NULL, *pchan;
3843 int result, status = L2CAP_CS_NO_INFO;
3844
3845 u16 dcid = 0, scid = __le16_to_cpu(req->scid);
3846 __le16 psm = req->psm;
3847
3848 BT_DBG("psm 0x%2.2x scid 0x%4.4x", __le16_to_cpu(psm), scid);
3849
3850 /* Check if we have socket listening on psm */
3851 pchan = l2cap_global_chan_by_psm(BT_LISTEN, psm, &conn->hcon->src,
3852 &conn->hcon->dst, ACL_LINK);
3853 if (!pchan) {
3854 result = L2CAP_CR_BAD_PSM;
3855 goto sendresp;
3856 }
3857
3858 mutex_lock(&conn->chan_lock);
3859 l2cap_chan_lock(pchan);
3860
3861 /* Check if the ACL is secure enough (if not SDP) */
3862 if (psm != cpu_to_le16(L2CAP_PSM_SDP) &&
3863 !hci_conn_check_link_mode(conn->hcon)) {
3864 conn->disc_reason = HCI_ERROR_AUTH_FAILURE;
3865 result = L2CAP_CR_SEC_BLOCK;
3866 goto response;
3867 }
3868
3869 result = L2CAP_CR_NO_MEM;
3870
3871 /* Check for valid dynamic CID range (as per Erratum 3253) */
3872 if (scid < L2CAP_CID_DYN_START || scid > L2CAP_CID_DYN_END) {
3873 result = L2CAP_CR_INVALID_SCID;
3874 goto response;
3875 }
3876
3877 /* Check if we already have channel with that dcid */
3878 if (__l2cap_get_chan_by_dcid(conn, scid)) {
3879 result = L2CAP_CR_SCID_IN_USE;
3880 goto response;
3881 }
3882
3883 chan = pchan->ops->new_connection(pchan);
3884 if (!chan)
3885 goto response;
3886
3887 /* For certain devices (ex: HID mouse), support for authentication,
3888 * pairing and bonding is optional. For such devices, inorder to avoid
3889 * the ACL alive for too long after L2CAP disconnection, reset the ACL
3890 * disc_timeout back to HCI_DISCONN_TIMEOUT during L2CAP connect.
3891 */
3892 conn->hcon->disc_timeout = HCI_DISCONN_TIMEOUT;
3893
3894 bacpy(&chan->src, &conn->hcon->src);
3895 bacpy(&chan->dst, &conn->hcon->dst);
3896 chan->src_type = bdaddr_src_type(conn->hcon);
3897 chan->dst_type = bdaddr_dst_type(conn->hcon);
3898 chan->psm = psm;
3899 chan->dcid = scid;
3900 chan->local_amp_id = amp_id;
3901
3902 __l2cap_chan_add(conn, chan);
3903
3904 dcid = chan->scid;
3905
3906 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
3907
3908 chan->ident = cmd->ident;
3909
3910 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE) {
3911 if (l2cap_chan_check_security(chan, false)) {
3912 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
3913 l2cap_state_change(chan, BT_CONNECT2);
3914 result = L2CAP_CR_PEND;
3915 status = L2CAP_CS_AUTHOR_PEND;
3916 chan->ops->defer(chan);
3917 } else {
3918 /* Force pending result for AMP controllers.
3919 * The connection will succeed after the
3920 * physical link is up.
3921 */
3922 if (amp_id == AMP_ID_BREDR) {
3923 l2cap_state_change(chan, BT_CONFIG);
3924 result = L2CAP_CR_SUCCESS;
3925 } else {
3926 l2cap_state_change(chan, BT_CONNECT2);
3927 result = L2CAP_CR_PEND;
3928 }
3929 status = L2CAP_CS_NO_INFO;
3930 }
3931 } else {
3932 l2cap_state_change(chan, BT_CONNECT2);
3933 result = L2CAP_CR_PEND;
3934 status = L2CAP_CS_AUTHEN_PEND;
3935 }
3936 } else {
3937 l2cap_state_change(chan, BT_CONNECT2);
3938 result = L2CAP_CR_PEND;
3939 status = L2CAP_CS_NO_INFO;
3940 }
3941
3942response:
3943 l2cap_chan_unlock(pchan);
3944 mutex_unlock(&conn->chan_lock);
3945 l2cap_chan_put(pchan);
3946
3947sendresp:
3948 rsp.scid = cpu_to_le16(scid);
3949 rsp.dcid = cpu_to_le16(dcid);
3950 rsp.result = cpu_to_le16(result);
3951 rsp.status = cpu_to_le16(status);
3952 l2cap_send_cmd(conn, cmd->ident, rsp_code, sizeof(rsp), &rsp);
3953
3954 if (result == L2CAP_CR_PEND && status == L2CAP_CS_NO_INFO) {
3955 struct l2cap_info_req info;
3956 info.type = cpu_to_le16(L2CAP_IT_FEAT_MASK);
3957
3958 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_SENT;
3959 conn->info_ident = l2cap_get_ident(conn);
3960
3961 schedule_delayed_work(&conn->info_timer, L2CAP_INFO_TIMEOUT);
3962
3963 l2cap_send_cmd(conn, conn->info_ident, L2CAP_INFO_REQ,
3964 sizeof(info), &info);
3965 }
3966
3967 if (chan && !test_bit(CONF_REQ_SENT, &chan->conf_state) &&
3968 result == L2CAP_CR_SUCCESS) {
3969 u8 buf[128];
3970 set_bit(CONF_REQ_SENT, &chan->conf_state);
3971 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
3972 l2cap_build_conf_req(chan, buf, sizeof(buf)), buf);
3973 chan->num_conf_req++;
3974 }
3975
3976 return chan;
3977}
3978
3979static int l2cap_connect_req(struct l2cap_conn *conn,
3980 struct l2cap_cmd_hdr *cmd, u16 cmd_len, u8 *data)
3981{
3982 struct hci_dev *hdev = conn->hcon->hdev;
3983 struct hci_conn *hcon = conn->hcon;
3984
3985 if (cmd_len < sizeof(struct l2cap_conn_req))
3986 return -EPROTO;
3987
3988 hci_dev_lock(hdev);
3989 if (hci_dev_test_flag(hdev, HCI_MGMT) &&
3990 !test_and_set_bit(HCI_CONN_MGMT_CONNECTED, &hcon->flags))
3991 mgmt_device_connected(hdev, hcon, 0, NULL, 0);
3992 hci_dev_unlock(hdev);
3993
3994 l2cap_connect(conn, cmd, data, L2CAP_CONN_RSP, 0);
3995 return 0;
3996}
3997
3998static int l2cap_connect_create_rsp(struct l2cap_conn *conn,
3999 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4000 u8 *data)
4001{
4002 struct l2cap_conn_rsp *rsp = (struct l2cap_conn_rsp *) data;
4003 u16 scid, dcid, result, status;
4004 struct l2cap_chan *chan;
4005 u8 req[128];
4006 int err;
4007
4008 if (cmd_len < sizeof(*rsp))
4009 return -EPROTO;
4010
4011 scid = __le16_to_cpu(rsp->scid);
4012 dcid = __le16_to_cpu(rsp->dcid);
4013 result = __le16_to_cpu(rsp->result);
4014 status = __le16_to_cpu(rsp->status);
4015
4016 BT_DBG("dcid 0x%4.4x scid 0x%4.4x result 0x%2.2x status 0x%2.2x",
4017 dcid, scid, result, status);
4018
4019 mutex_lock(&conn->chan_lock);
4020
4021 if (scid) {
4022 chan = __l2cap_get_chan_by_scid(conn, scid);
4023 if (!chan) {
4024 err = -EBADSLT;
4025 goto unlock;
4026 }
4027 } else {
4028 chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
4029 if (!chan) {
4030 err = -EBADSLT;
4031 goto unlock;
4032 }
4033 }
4034
4035 err = 0;
4036
4037 l2cap_chan_lock(chan);
4038
4039 switch (result) {
4040 case L2CAP_CR_SUCCESS:
4041 l2cap_state_change(chan, BT_CONFIG);
4042 chan->ident = 0;
4043 chan->dcid = dcid;
4044 clear_bit(CONF_CONNECT_PEND, &chan->conf_state);
4045
4046 if (test_and_set_bit(CONF_REQ_SENT, &chan->conf_state))
4047 break;
4048
4049 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
4050 l2cap_build_conf_req(chan, req, sizeof(req)), req);
4051 chan->num_conf_req++;
4052 break;
4053
4054 case L2CAP_CR_PEND:
4055 set_bit(CONF_CONNECT_PEND, &chan->conf_state);
4056 break;
4057
4058 default:
4059 l2cap_chan_del(chan, ECONNREFUSED);
4060 break;
4061 }
4062
4063 l2cap_chan_unlock(chan);
4064
4065unlock:
4066 mutex_unlock(&conn->chan_lock);
4067
4068 return err;
4069}
4070
4071static inline void set_default_fcs(struct l2cap_chan *chan)
4072{
4073 /* FCS is enabled only in ERTM or streaming mode, if one or both
4074 * sides request it.
4075 */
4076 if (chan->mode != L2CAP_MODE_ERTM && chan->mode != L2CAP_MODE_STREAMING)
4077 chan->fcs = L2CAP_FCS_NONE;
4078 else if (!test_bit(CONF_RECV_NO_FCS, &chan->conf_state))
4079 chan->fcs = L2CAP_FCS_CRC16;
4080}
4081
4082static void l2cap_send_efs_conf_rsp(struct l2cap_chan *chan, void *data,
4083 u8 ident, u16 flags)
4084{
4085 struct l2cap_conn *conn = chan->conn;
4086
4087 BT_DBG("conn %p chan %p ident %d flags 0x%4.4x", conn, chan, ident,
4088 flags);
4089
4090 clear_bit(CONF_LOC_CONF_PEND, &chan->conf_state);
4091 set_bit(CONF_OUTPUT_DONE, &chan->conf_state);
4092
4093 l2cap_send_cmd(conn, ident, L2CAP_CONF_RSP,
4094 l2cap_build_conf_rsp(chan, data,
4095 L2CAP_CONF_SUCCESS, flags), data);
4096}
4097
4098static void cmd_reject_invalid_cid(struct l2cap_conn *conn, u8 ident,
4099 u16 scid, u16 dcid)
4100{
4101 struct l2cap_cmd_rej_cid rej;
4102
4103 rej.reason = cpu_to_le16(L2CAP_REJ_INVALID_CID);
4104 rej.scid = __cpu_to_le16(scid);
4105 rej.dcid = __cpu_to_le16(dcid);
4106
4107 l2cap_send_cmd(conn, ident, L2CAP_COMMAND_REJ, sizeof(rej), &rej);
4108}
4109
4110static inline int l2cap_config_req(struct l2cap_conn *conn,
4111 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4112 u8 *data)
4113{
4114 struct l2cap_conf_req *req = (struct l2cap_conf_req *) data;
4115 u16 dcid, flags;
4116 u8 rsp[64];
4117 struct l2cap_chan *chan;
4118 int len, err = 0;
4119
4120 if (cmd_len < sizeof(*req))
4121 return -EPROTO;
4122
4123 dcid = __le16_to_cpu(req->dcid);
4124 flags = __le16_to_cpu(req->flags);
4125
4126 BT_DBG("dcid 0x%4.4x flags 0x%2.2x", dcid, flags);
4127
4128 chan = l2cap_get_chan_by_scid(conn, dcid);
4129 if (!chan) {
4130 cmd_reject_invalid_cid(conn, cmd->ident, dcid, 0);
4131 return 0;
4132 }
4133
4134 if (chan->state != BT_CONFIG && chan->state != BT_CONNECT2) {
4135 cmd_reject_invalid_cid(conn, cmd->ident, chan->scid,
4136 chan->dcid);
4137 goto unlock;
4138 }
4139
4140 /* Reject if config buffer is too small. */
4141 len = cmd_len - sizeof(*req);
4142 if (chan->conf_len + len > sizeof(chan->conf_req)) {
4143 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP,
4144 l2cap_build_conf_rsp(chan, rsp,
4145 L2CAP_CONF_REJECT, flags), rsp);
4146 goto unlock;
4147 }
4148
4149 /* Store config. */
4150 memcpy(chan->conf_req + chan->conf_len, req->data, len);
4151 chan->conf_len += len;
4152
4153 if (flags & L2CAP_CONF_FLAG_CONTINUATION) {
4154 /* Incomplete config. Send empty response. */
4155 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP,
4156 l2cap_build_conf_rsp(chan, rsp,
4157 L2CAP_CONF_SUCCESS, flags), rsp);
4158 goto unlock;
4159 }
4160
4161 /* Complete config. */
4162 len = l2cap_parse_conf_req(chan, rsp, sizeof(rsp));
4163 if (len < 0) {
4164 l2cap_send_disconn_req(chan, ECONNRESET);
4165 goto unlock;
4166 }
4167
4168 chan->ident = cmd->ident;
4169 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP, len, rsp);
4170 chan->num_conf_rsp++;
4171
4172 /* Reset config buffer. */
4173 chan->conf_len = 0;
4174
4175 if (!test_bit(CONF_OUTPUT_DONE, &chan->conf_state))
4176 goto unlock;
4177
4178 if (test_bit(CONF_INPUT_DONE, &chan->conf_state)) {
4179 set_default_fcs(chan);
4180
4181 if (chan->mode == L2CAP_MODE_ERTM ||
4182 chan->mode == L2CAP_MODE_STREAMING)
4183 err = l2cap_ertm_init(chan);
4184
4185 if (err < 0)
4186 l2cap_send_disconn_req(chan, -err);
4187 else
4188 l2cap_chan_ready(chan);
4189
4190 goto unlock;
4191 }
4192
4193 if (!test_and_set_bit(CONF_REQ_SENT, &chan->conf_state)) {
4194 u8 buf[64];
4195 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
4196 l2cap_build_conf_req(chan, buf, sizeof(buf)), buf);
4197 chan->num_conf_req++;
4198 }
4199
4200 /* Got Conf Rsp PENDING from remote side and assume we sent
4201 Conf Rsp PENDING in the code above */
4202 if (test_bit(CONF_REM_CONF_PEND, &chan->conf_state) &&
4203 test_bit(CONF_LOC_CONF_PEND, &chan->conf_state)) {
4204
4205 /* check compatibility */
4206
4207 /* Send rsp for BR/EDR channel */
4208 if (!chan->hs_hcon)
4209 l2cap_send_efs_conf_rsp(chan, rsp, cmd->ident, flags);
4210 else
4211 chan->ident = cmd->ident;
4212 }
4213
4214unlock:
4215 l2cap_chan_unlock(chan);
4216 return err;
4217}
4218
4219static inline int l2cap_config_rsp(struct l2cap_conn *conn,
4220 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4221 u8 *data)
4222{
4223 struct l2cap_conf_rsp *rsp = (struct l2cap_conf_rsp *)data;
4224 u16 scid, flags, result;
4225 struct l2cap_chan *chan;
4226 int len = cmd_len - sizeof(*rsp);
4227 int err = 0;
4228
4229 if (cmd_len < sizeof(*rsp))
4230 return -EPROTO;
4231
4232 scid = __le16_to_cpu(rsp->scid);
4233 flags = __le16_to_cpu(rsp->flags);
4234 result = __le16_to_cpu(rsp->result);
4235
4236 BT_DBG("scid 0x%4.4x flags 0x%2.2x result 0x%2.2x len %d", scid, flags,
4237 result, len);
4238
4239 chan = l2cap_get_chan_by_scid(conn, scid);
4240 if (!chan)
4241 return 0;
4242
4243 switch (result) {
4244 case L2CAP_CONF_SUCCESS:
4245 l2cap_conf_rfc_get(chan, rsp->data, len);
4246 clear_bit(CONF_REM_CONF_PEND, &chan->conf_state);
4247 break;
4248
4249 case L2CAP_CONF_PENDING:
4250 set_bit(CONF_REM_CONF_PEND, &chan->conf_state);
4251
4252 if (test_bit(CONF_LOC_CONF_PEND, &chan->conf_state)) {
4253 char buf[64];
4254
4255 len = l2cap_parse_conf_rsp(chan, rsp->data, len,
4256 buf, sizeof(buf), &result);
4257 if (len < 0) {
4258 l2cap_send_disconn_req(chan, ECONNRESET);
4259 goto done;
4260 }
4261
4262 if (!chan->hs_hcon) {
4263 l2cap_send_efs_conf_rsp(chan, buf, cmd->ident,
4264 0);
4265 } else {
4266 if (l2cap_check_efs(chan)) {
4267 amp_create_logical_link(chan);
4268 chan->ident = cmd->ident;
4269 }
4270 }
4271 }
4272 goto done;
4273
4274 case L2CAP_CONF_UNACCEPT:
4275 if (chan->num_conf_rsp <= L2CAP_CONF_MAX_CONF_RSP) {
4276 char req[64];
4277
4278 if (len > sizeof(req) - sizeof(struct l2cap_conf_req)) {
4279 l2cap_send_disconn_req(chan, ECONNRESET);
4280 goto done;
4281 }
4282
4283 /* throw out any old stored conf requests */
4284 result = L2CAP_CONF_SUCCESS;
4285 len = l2cap_parse_conf_rsp(chan, rsp->data, len,
4286 req, sizeof(req), &result);
4287 if (len < 0) {
4288 l2cap_send_disconn_req(chan, ECONNRESET);
4289 goto done;
4290 }
4291
4292 l2cap_send_cmd(conn, l2cap_get_ident(conn),
4293 L2CAP_CONF_REQ, len, req);
4294 chan->num_conf_req++;
4295 if (result != L2CAP_CONF_SUCCESS)
4296 goto done;
4297 break;
4298 }
4299 /* fall through */
4300
4301 default:
4302 l2cap_chan_set_err(chan, ECONNRESET);
4303
4304 __set_chan_timer(chan, L2CAP_DISC_REJ_TIMEOUT);
4305 l2cap_send_disconn_req(chan, ECONNRESET);
4306 goto done;
4307 }
4308
4309 if (flags & L2CAP_CONF_FLAG_CONTINUATION)
4310 goto done;
4311
4312 set_bit(CONF_INPUT_DONE, &chan->conf_state);
4313
4314 if (test_bit(CONF_OUTPUT_DONE, &chan->conf_state)) {
4315 set_default_fcs(chan);
4316
4317 if (chan->mode == L2CAP_MODE_ERTM ||
4318 chan->mode == L2CAP_MODE_STREAMING)
4319 err = l2cap_ertm_init(chan);
4320
4321 if (err < 0)
4322 l2cap_send_disconn_req(chan, -err);
4323 else
4324 l2cap_chan_ready(chan);
4325 }
4326
4327done:
4328 l2cap_chan_unlock(chan);
4329 return err;
4330}
4331
4332static inline int l2cap_disconnect_req(struct l2cap_conn *conn,
4333 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4334 u8 *data)
4335{
4336 struct l2cap_disconn_req *req = (struct l2cap_disconn_req *) data;
4337 struct l2cap_disconn_rsp rsp;
4338 u16 dcid, scid;
4339 struct l2cap_chan *chan;
4340
4341 if (cmd_len != sizeof(*req))
4342 return -EPROTO;
4343
4344 scid = __le16_to_cpu(req->scid);
4345 dcid = __le16_to_cpu(req->dcid);
4346
4347 BT_DBG("scid 0x%4.4x dcid 0x%4.4x", scid, dcid);
4348
4349 mutex_lock(&conn->chan_lock);
4350
4351 chan = __l2cap_get_chan_by_scid(conn, dcid);
4352 if (!chan) {
4353 mutex_unlock(&conn->chan_lock);
4354 cmd_reject_invalid_cid(conn, cmd->ident, dcid, scid);
4355 return 0;
4356 }
4357
4358 l2cap_chan_lock(chan);
4359
4360 rsp.dcid = cpu_to_le16(chan->scid);
4361 rsp.scid = cpu_to_le16(chan->dcid);
4362 l2cap_send_cmd(conn, cmd->ident, L2CAP_DISCONN_RSP, sizeof(rsp), &rsp);
4363
4364 chan->ops->set_shutdown(chan);
4365
4366 l2cap_chan_hold(chan);
4367 l2cap_chan_del(chan, ECONNRESET);
4368
4369 l2cap_chan_unlock(chan);
4370
4371 chan->ops->close(chan);
4372 l2cap_chan_put(chan);
4373
4374 mutex_unlock(&conn->chan_lock);
4375
4376 return 0;
4377}
4378
4379static inline int l2cap_disconnect_rsp(struct l2cap_conn *conn,
4380 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4381 u8 *data)
4382{
4383 struct l2cap_disconn_rsp *rsp = (struct l2cap_disconn_rsp *) data;
4384 u16 dcid, scid;
4385 struct l2cap_chan *chan;
4386
4387 if (cmd_len != sizeof(*rsp))
4388 return -EPROTO;
4389
4390 scid = __le16_to_cpu(rsp->scid);
4391 dcid = __le16_to_cpu(rsp->dcid);
4392
4393 BT_DBG("dcid 0x%4.4x scid 0x%4.4x", dcid, scid);
4394
4395 mutex_lock(&conn->chan_lock);
4396
4397 chan = __l2cap_get_chan_by_scid(conn, scid);
4398 if (!chan) {
4399 mutex_unlock(&conn->chan_lock);
4400 return 0;
4401 }
4402
4403 l2cap_chan_lock(chan);
4404
4405 if (chan->state != BT_DISCONN) {
4406 l2cap_chan_unlock(chan);
4407 mutex_unlock(&conn->chan_lock);
4408 return 0;
4409 }
4410
4411 l2cap_chan_hold(chan);
4412 l2cap_chan_del(chan, 0);
4413
4414 l2cap_chan_unlock(chan);
4415
4416 chan->ops->close(chan);
4417 l2cap_chan_put(chan);
4418
4419 mutex_unlock(&conn->chan_lock);
4420
4421 return 0;
4422}
4423
4424static inline int l2cap_information_req(struct l2cap_conn *conn,
4425 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4426 u8 *data)
4427{
4428 struct l2cap_info_req *req = (struct l2cap_info_req *) data;
4429 u16 type;
4430
4431 if (cmd_len != sizeof(*req))
4432 return -EPROTO;
4433
4434 type = __le16_to_cpu(req->type);
4435
4436 BT_DBG("type 0x%4.4x", type);
4437
4438 if (type == L2CAP_IT_FEAT_MASK) {
4439 u8 buf[8];
4440 u32 feat_mask = l2cap_feat_mask;
4441 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) buf;
4442 rsp->type = cpu_to_le16(L2CAP_IT_FEAT_MASK);
4443 rsp->result = cpu_to_le16(L2CAP_IR_SUCCESS);
4444 if (!disable_ertm)
4445 feat_mask |= L2CAP_FEAT_ERTM | L2CAP_FEAT_STREAMING
4446 | L2CAP_FEAT_FCS;
4447 if (conn->local_fixed_chan & L2CAP_FC_A2MP)
4448 feat_mask |= L2CAP_FEAT_EXT_FLOW
4449 | L2CAP_FEAT_EXT_WINDOW;
4450
4451 put_unaligned_le32(feat_mask, rsp->data);
4452 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(buf),
4453 buf);
4454 } else if (type == L2CAP_IT_FIXED_CHAN) {
4455 u8 buf[12];
4456 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) buf;
4457
4458 rsp->type = cpu_to_le16(L2CAP_IT_FIXED_CHAN);
4459 rsp->result = cpu_to_le16(L2CAP_IR_SUCCESS);
4460 rsp->data[0] = conn->local_fixed_chan;
4461 memset(rsp->data + 1, 0, 7);
4462 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(buf),
4463 buf);
4464 } else {
4465 struct l2cap_info_rsp rsp;
4466 rsp.type = cpu_to_le16(type);
4467 rsp.result = cpu_to_le16(L2CAP_IR_NOTSUPP);
4468 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(rsp),
4469 &rsp);
4470 }
4471
4472 return 0;
4473}
4474
4475static inline int l2cap_information_rsp(struct l2cap_conn *conn,
4476 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4477 u8 *data)
4478{
4479 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) data;
4480 u16 type, result;
4481
4482 if (cmd_len < sizeof(*rsp))
4483 return -EPROTO;
4484
4485 type = __le16_to_cpu(rsp->type);
4486 result = __le16_to_cpu(rsp->result);
4487
4488 BT_DBG("type 0x%4.4x result 0x%2.2x", type, result);
4489
4490 /* L2CAP Info req/rsp are unbound to channels, add extra checks */
4491 if (cmd->ident != conn->info_ident ||
4492 conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE)
4493 return 0;
4494
4495 cancel_delayed_work(&conn->info_timer);
4496
4497 if (result != L2CAP_IR_SUCCESS) {
4498 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4499 conn->info_ident = 0;
4500
4501 l2cap_conn_start(conn);
4502
4503 return 0;
4504 }
4505
4506 switch (type) {
4507 case L2CAP_IT_FEAT_MASK:
4508 conn->feat_mask = get_unaligned_le32(rsp->data);
4509
4510 if (conn->feat_mask & L2CAP_FEAT_FIXED_CHAN) {
4511 struct l2cap_info_req req;
4512 req.type = cpu_to_le16(L2CAP_IT_FIXED_CHAN);
4513
4514 conn->info_ident = l2cap_get_ident(conn);
4515
4516 l2cap_send_cmd(conn, conn->info_ident,
4517 L2CAP_INFO_REQ, sizeof(req), &req);
4518 } else {
4519 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4520 conn->info_ident = 0;
4521
4522 l2cap_conn_start(conn);
4523 }
4524 break;
4525
4526 case L2CAP_IT_FIXED_CHAN:
4527 conn->remote_fixed_chan = rsp->data[0];
4528 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4529 conn->info_ident = 0;
4530
4531 l2cap_conn_start(conn);
4532 break;
4533 }
4534
4535 return 0;
4536}
4537
4538static int l2cap_create_channel_req(struct l2cap_conn *conn,
4539 struct l2cap_cmd_hdr *cmd,
4540 u16 cmd_len, void *data)
4541{
4542 struct l2cap_create_chan_req *req = data;
4543 struct l2cap_create_chan_rsp rsp;
4544 struct l2cap_chan *chan;
4545 struct hci_dev *hdev;
4546 u16 psm, scid;
4547
4548 if (cmd_len != sizeof(*req))
4549 return -EPROTO;
4550
4551 if (!(conn->local_fixed_chan & L2CAP_FC_A2MP))
4552 return -EINVAL;
4553
4554 psm = le16_to_cpu(req->psm);
4555 scid = le16_to_cpu(req->scid);
4556
4557 BT_DBG("psm 0x%2.2x, scid 0x%4.4x, amp_id %d", psm, scid, req->amp_id);
4558
4559 /* For controller id 0 make BR/EDR connection */
4560 if (req->amp_id == AMP_ID_BREDR) {
4561 l2cap_connect(conn, cmd, data, L2CAP_CREATE_CHAN_RSP,
4562 req->amp_id);
4563 return 0;
4564 }
4565
4566 /* Validate AMP controller id */
4567 hdev = hci_dev_get(req->amp_id);
4568 if (!hdev)
4569 goto error;
4570
4571 if (hdev->dev_type != HCI_AMP || !test_bit(HCI_UP, &hdev->flags)) {
4572 hci_dev_put(hdev);
4573 goto error;
4574 }
4575
4576 chan = l2cap_connect(conn, cmd, data, L2CAP_CREATE_CHAN_RSP,
4577 req->amp_id);
4578 if (chan) {
4579 struct amp_mgr *mgr = conn->hcon->amp_mgr;
4580 struct hci_conn *hs_hcon;
4581
4582 hs_hcon = hci_conn_hash_lookup_ba(hdev, AMP_LINK,
4583 &conn->hcon->dst);
4584 if (!hs_hcon) {
4585 hci_dev_put(hdev);
4586 cmd_reject_invalid_cid(conn, cmd->ident, chan->scid,
4587 chan->dcid);
4588 return 0;
4589 }
4590
4591 BT_DBG("mgr %p bredr_chan %p hs_hcon %p", mgr, chan, hs_hcon);
4592
4593 mgr->bredr_chan = chan;
4594 chan->hs_hcon = hs_hcon;
4595 chan->fcs = L2CAP_FCS_NONE;
4596 conn->mtu = hdev->block_mtu;
4597 }
4598
4599 hci_dev_put(hdev);
4600
4601 return 0;
4602
4603error:
4604 rsp.dcid = 0;
4605 rsp.scid = cpu_to_le16(scid);
4606 rsp.result = cpu_to_le16(L2CAP_CR_BAD_AMP);
4607 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
4608
4609 l2cap_send_cmd(conn, cmd->ident, L2CAP_CREATE_CHAN_RSP,
4610 sizeof(rsp), &rsp);
4611
4612 return 0;
4613}
4614
4615static void l2cap_send_move_chan_req(struct l2cap_chan *chan, u8 dest_amp_id)
4616{
4617 struct l2cap_move_chan_req req;
4618 u8 ident;
4619
4620 BT_DBG("chan %p, dest_amp_id %d", chan, dest_amp_id);
4621
4622 ident = l2cap_get_ident(chan->conn);
4623 chan->ident = ident;
4624
4625 req.icid = cpu_to_le16(chan->scid);
4626 req.dest_amp_id = dest_amp_id;
4627
4628 l2cap_send_cmd(chan->conn, ident, L2CAP_MOVE_CHAN_REQ, sizeof(req),
4629 &req);
4630
4631 __set_chan_timer(chan, L2CAP_MOVE_TIMEOUT);
4632}
4633
4634static void l2cap_send_move_chan_rsp(struct l2cap_chan *chan, u16 result)
4635{
4636 struct l2cap_move_chan_rsp rsp;
4637
4638 BT_DBG("chan %p, result 0x%4.4x", chan, result);
4639
4640 rsp.icid = cpu_to_le16(chan->dcid);
4641 rsp.result = cpu_to_le16(result);
4642
4643 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_MOVE_CHAN_RSP,
4644 sizeof(rsp), &rsp);
4645}
4646
4647static void l2cap_send_move_chan_cfm(struct l2cap_chan *chan, u16 result)
4648{
4649 struct l2cap_move_chan_cfm cfm;
4650
4651 BT_DBG("chan %p, result 0x%4.4x", chan, result);
4652
4653 chan->ident = l2cap_get_ident(chan->conn);
4654
4655 cfm.icid = cpu_to_le16(chan->scid);
4656 cfm.result = cpu_to_le16(result);
4657
4658 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_MOVE_CHAN_CFM,
4659 sizeof(cfm), &cfm);
4660
4661 __set_chan_timer(chan, L2CAP_MOVE_TIMEOUT);
4662}
4663
4664static void l2cap_send_move_chan_cfm_icid(struct l2cap_conn *conn, u16 icid)
4665{
4666 struct l2cap_move_chan_cfm cfm;
4667
4668 BT_DBG("conn %p, icid 0x%4.4x", conn, icid);
4669
4670 cfm.icid = cpu_to_le16(icid);
4671 cfm.result = cpu_to_le16(L2CAP_MC_UNCONFIRMED);
4672
4673 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_MOVE_CHAN_CFM,
4674 sizeof(cfm), &cfm);
4675}
4676
4677static void l2cap_send_move_chan_cfm_rsp(struct l2cap_conn *conn, u8 ident,
4678 u16 icid)
4679{
4680 struct l2cap_move_chan_cfm_rsp rsp;
4681
4682 BT_DBG("icid 0x%4.4x", icid);
4683
4684 rsp.icid = cpu_to_le16(icid);
4685 l2cap_send_cmd(conn, ident, L2CAP_MOVE_CHAN_CFM_RSP, sizeof(rsp), &rsp);
4686}
4687
4688static void __release_logical_link(struct l2cap_chan *chan)
4689{
4690 chan->hs_hchan = NULL;
4691 chan->hs_hcon = NULL;
4692
4693 /* Placeholder - release the logical link */
4694}
4695
4696static void l2cap_logical_fail(struct l2cap_chan *chan)
4697{
4698 /* Logical link setup failed */
4699 if (chan->state != BT_CONNECTED) {
4700 /* Create channel failure, disconnect */
4701 l2cap_send_disconn_req(chan, ECONNRESET);
4702 return;
4703 }
4704
4705 switch (chan->move_role) {
4706 case L2CAP_MOVE_ROLE_RESPONDER:
4707 l2cap_move_done(chan);
4708 l2cap_send_move_chan_rsp(chan, L2CAP_MR_NOT_SUPP);
4709 break;
4710 case L2CAP_MOVE_ROLE_INITIATOR:
4711 if (chan->move_state == L2CAP_MOVE_WAIT_LOGICAL_COMP ||
4712 chan->move_state == L2CAP_MOVE_WAIT_LOGICAL_CFM) {
4713 /* Remote has only sent pending or
4714 * success responses, clean up
4715 */
4716 l2cap_move_done(chan);
4717 }
4718
4719 /* Other amp move states imply that the move
4720 * has already aborted
4721 */
4722 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
4723 break;
4724 }
4725}
4726
4727static void l2cap_logical_finish_create(struct l2cap_chan *chan,
4728 struct hci_chan *hchan)
4729{
4730 struct l2cap_conf_rsp rsp;
4731
4732 chan->hs_hchan = hchan;
4733 chan->hs_hcon->l2cap_data = chan->conn;
4734
4735 l2cap_send_efs_conf_rsp(chan, &rsp, chan->ident, 0);
4736
4737 if (test_bit(CONF_INPUT_DONE, &chan->conf_state)) {
4738 int err;
4739
4740 set_default_fcs(chan);
4741
4742 err = l2cap_ertm_init(chan);
4743 if (err < 0)
4744 l2cap_send_disconn_req(chan, -err);
4745 else
4746 l2cap_chan_ready(chan);
4747 }
4748}
4749
4750static void l2cap_logical_finish_move(struct l2cap_chan *chan,
4751 struct hci_chan *hchan)
4752{
4753 chan->hs_hcon = hchan->conn;
4754 chan->hs_hcon->l2cap_data = chan->conn;
4755
4756 BT_DBG("move_state %d", chan->move_state);
4757
4758 switch (chan->move_state) {
4759 case L2CAP_MOVE_WAIT_LOGICAL_COMP:
4760 /* Move confirm will be sent after a success
4761 * response is received
4762 */
4763 chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
4764 break;
4765 case L2CAP_MOVE_WAIT_LOGICAL_CFM:
4766 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
4767 chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
4768 } else if (chan->move_role == L2CAP_MOVE_ROLE_INITIATOR) {
4769 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM_RSP;
4770 l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
4771 } else if (chan->move_role == L2CAP_MOVE_ROLE_RESPONDER) {
4772 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
4773 l2cap_send_move_chan_rsp(chan, L2CAP_MR_SUCCESS);
4774 }
4775 break;
4776 default:
4777 /* Move was not in expected state, free the channel */
4778 __release_logical_link(chan);
4779
4780 chan->move_state = L2CAP_MOVE_STABLE;
4781 }
4782}
4783
4784/* Call with chan locked */
4785void l2cap_logical_cfm(struct l2cap_chan *chan, struct hci_chan *hchan,
4786 u8 status)
4787{
4788 BT_DBG("chan %p, hchan %p, status %d", chan, hchan, status);
4789
4790 if (status) {
4791 l2cap_logical_fail(chan);
4792 __release_logical_link(chan);
4793 return;
4794 }
4795
4796 if (chan->state != BT_CONNECTED) {
4797 /* Ignore logical link if channel is on BR/EDR */
4798 if (chan->local_amp_id != AMP_ID_BREDR)
4799 l2cap_logical_finish_create(chan, hchan);
4800 } else {
4801 l2cap_logical_finish_move(chan, hchan);
4802 }
4803}
4804
4805void l2cap_move_start(struct l2cap_chan *chan)
4806{
4807 BT_DBG("chan %p", chan);
4808
4809 if (chan->local_amp_id == AMP_ID_BREDR) {
4810 if (chan->chan_policy != BT_CHANNEL_POLICY_AMP_PREFERRED)
4811 return;
4812 chan->move_role = L2CAP_MOVE_ROLE_INITIATOR;
4813 chan->move_state = L2CAP_MOVE_WAIT_PREPARE;
4814 /* Placeholder - start physical link setup */
4815 } else {
4816 chan->move_role = L2CAP_MOVE_ROLE_INITIATOR;
4817 chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
4818 chan->move_id = 0;
4819 l2cap_move_setup(chan);
4820 l2cap_send_move_chan_req(chan, 0);
4821 }
4822}
4823
4824static void l2cap_do_create(struct l2cap_chan *chan, int result,
4825 u8 local_amp_id, u8 remote_amp_id)
4826{
4827 BT_DBG("chan %p state %s %u -> %u", chan, state_to_string(chan->state),
4828 local_amp_id, remote_amp_id);
4829
4830 chan->fcs = L2CAP_FCS_NONE;
4831
4832 /* Outgoing channel on AMP */
4833 if (chan->state == BT_CONNECT) {
4834 if (result == L2CAP_CR_SUCCESS) {
4835 chan->local_amp_id = local_amp_id;
4836 l2cap_send_create_chan_req(chan, remote_amp_id);
4837 } else {
4838 /* Revert to BR/EDR connect */
4839 l2cap_send_conn_req(chan);
4840 }
4841
4842 return;
4843 }
4844
4845 /* Incoming channel on AMP */
4846 if (__l2cap_no_conn_pending(chan)) {
4847 struct l2cap_conn_rsp rsp;
4848 char buf[128];
4849 rsp.scid = cpu_to_le16(chan->dcid);
4850 rsp.dcid = cpu_to_le16(chan->scid);
4851
4852 if (result == L2CAP_CR_SUCCESS) {
4853 /* Send successful response */
4854 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
4855 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
4856 } else {
4857 /* Send negative response */
4858 rsp.result = cpu_to_le16(L2CAP_CR_NO_MEM);
4859 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
4860 }
4861
4862 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_CREATE_CHAN_RSP,
4863 sizeof(rsp), &rsp);
4864
4865 if (result == L2CAP_CR_SUCCESS) {
4866 l2cap_state_change(chan, BT_CONFIG);
4867 set_bit(CONF_REQ_SENT, &chan->conf_state);
4868 l2cap_send_cmd(chan->conn, l2cap_get_ident(chan->conn),
4869 L2CAP_CONF_REQ,
4870 l2cap_build_conf_req(chan, buf, sizeof(buf)), buf);
4871 chan->num_conf_req++;
4872 }
4873 }
4874}
4875
4876static void l2cap_do_move_initiate(struct l2cap_chan *chan, u8 local_amp_id,
4877 u8 remote_amp_id)
4878{
4879 l2cap_move_setup(chan);
4880 chan->move_id = local_amp_id;
4881 chan->move_state = L2CAP_MOVE_WAIT_RSP;
4882
4883 l2cap_send_move_chan_req(chan, remote_amp_id);
4884}
4885
4886static void l2cap_do_move_respond(struct l2cap_chan *chan, int result)
4887{
4888 struct hci_chan *hchan = NULL;
4889
4890 /* Placeholder - get hci_chan for logical link */
4891
4892 if (hchan) {
4893 if (hchan->state == BT_CONNECTED) {
4894 /* Logical link is ready to go */
4895 chan->hs_hcon = hchan->conn;
4896 chan->hs_hcon->l2cap_data = chan->conn;
4897 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
4898 l2cap_send_move_chan_rsp(chan, L2CAP_MR_SUCCESS);
4899
4900 l2cap_logical_cfm(chan, hchan, L2CAP_MR_SUCCESS);
4901 } else {
4902 /* Wait for logical link to be ready */
4903 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
4904 }
4905 } else {
4906 /* Logical link not available */
4907 l2cap_send_move_chan_rsp(chan, L2CAP_MR_NOT_ALLOWED);
4908 }
4909}
4910
4911static void l2cap_do_move_cancel(struct l2cap_chan *chan, int result)
4912{
4913 if (chan->move_role == L2CAP_MOVE_ROLE_RESPONDER) {
4914 u8 rsp_result;
4915 if (result == -EINVAL)
4916 rsp_result = L2CAP_MR_BAD_ID;
4917 else
4918 rsp_result = L2CAP_MR_NOT_ALLOWED;
4919
4920 l2cap_send_move_chan_rsp(chan, rsp_result);
4921 }
4922
4923 chan->move_role = L2CAP_MOVE_ROLE_NONE;
4924 chan->move_state = L2CAP_MOVE_STABLE;
4925
4926 /* Restart data transmission */
4927 l2cap_ertm_send(chan);
4928}
4929
4930/* Invoke with locked chan */
4931void __l2cap_physical_cfm(struct l2cap_chan *chan, int result)
4932{
4933 u8 local_amp_id = chan->local_amp_id;
4934 u8 remote_amp_id = chan->remote_amp_id;
4935
4936 BT_DBG("chan %p, result %d, local_amp_id %d, remote_amp_id %d",
4937 chan, result, local_amp_id, remote_amp_id);
4938
4939 if (chan->state == BT_DISCONN || chan->state == BT_CLOSED) {
4940 l2cap_chan_unlock(chan);
4941 return;
4942 }
4943
4944 if (chan->state != BT_CONNECTED) {
4945 l2cap_do_create(chan, result, local_amp_id, remote_amp_id);
4946 } else if (result != L2CAP_MR_SUCCESS) {
4947 l2cap_do_move_cancel(chan, result);
4948 } else {
4949 switch (chan->move_role) {
4950 case L2CAP_MOVE_ROLE_INITIATOR:
4951 l2cap_do_move_initiate(chan, local_amp_id,
4952 remote_amp_id);
4953 break;
4954 case L2CAP_MOVE_ROLE_RESPONDER:
4955 l2cap_do_move_respond(chan, result);
4956 break;
4957 default:
4958 l2cap_do_move_cancel(chan, result);
4959 break;
4960 }
4961 }
4962}
4963
4964static inline int l2cap_move_channel_req(struct l2cap_conn *conn,
4965 struct l2cap_cmd_hdr *cmd,
4966 u16 cmd_len, void *data)
4967{
4968 struct l2cap_move_chan_req *req = data;
4969 struct l2cap_move_chan_rsp rsp;
4970 struct l2cap_chan *chan;
4971 u16 icid = 0;
4972 u16 result = L2CAP_MR_NOT_ALLOWED;
4973
4974 if (cmd_len != sizeof(*req))
4975 return -EPROTO;
4976
4977 icid = le16_to_cpu(req->icid);
4978
4979 BT_DBG("icid 0x%4.4x, dest_amp_id %d", icid, req->dest_amp_id);
4980
4981 if (!(conn->local_fixed_chan & L2CAP_FC_A2MP))
4982 return -EINVAL;
4983
4984 chan = l2cap_get_chan_by_dcid(conn, icid);
4985 if (!chan) {
4986 rsp.icid = cpu_to_le16(icid);
4987 rsp.result = cpu_to_le16(L2CAP_MR_NOT_ALLOWED);
4988 l2cap_send_cmd(conn, cmd->ident, L2CAP_MOVE_CHAN_RSP,
4989 sizeof(rsp), &rsp);
4990 return 0;
4991 }
4992
4993 chan->ident = cmd->ident;
4994
4995 if (chan->scid < L2CAP_CID_DYN_START ||
4996 chan->chan_policy == BT_CHANNEL_POLICY_BREDR_ONLY ||
4997 (chan->mode != L2CAP_MODE_ERTM &&
4998 chan->mode != L2CAP_MODE_STREAMING)) {
4999 result = L2CAP_MR_NOT_ALLOWED;
5000 goto send_move_response;
5001 }
5002
5003 if (chan->local_amp_id == req->dest_amp_id) {
5004 result = L2CAP_MR_SAME_ID;
5005 goto send_move_response;
5006 }
5007
5008 if (req->dest_amp_id != AMP_ID_BREDR) {
5009 struct hci_dev *hdev;
5010 hdev = hci_dev_get(req->dest_amp_id);
5011 if (!hdev || hdev->dev_type != HCI_AMP ||
5012 !test_bit(HCI_UP, &hdev->flags)) {
5013 if (hdev)
5014 hci_dev_put(hdev);
5015
5016 result = L2CAP_MR_BAD_ID;
5017 goto send_move_response;
5018 }
5019 hci_dev_put(hdev);
5020 }
5021
5022 /* Detect a move collision. Only send a collision response
5023 * if this side has "lost", otherwise proceed with the move.
5024 * The winner has the larger bd_addr.
5025 */
5026 if ((__chan_is_moving(chan) ||
5027 chan->move_role != L2CAP_MOVE_ROLE_NONE) &&
5028 bacmp(&conn->hcon->src, &conn->hcon->dst) > 0) {
5029 result = L2CAP_MR_COLLISION;
5030 goto send_move_response;
5031 }
5032
5033 chan->move_role = L2CAP_MOVE_ROLE_RESPONDER;
5034 l2cap_move_setup(chan);
5035 chan->move_id = req->dest_amp_id;
5036 icid = chan->dcid;
5037
5038 if (req->dest_amp_id == AMP_ID_BREDR) {
5039 /* Moving to BR/EDR */
5040 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
5041 chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
5042 result = L2CAP_MR_PEND;
5043 } else {
5044 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
5045 result = L2CAP_MR_SUCCESS;
5046 }
5047 } else {
5048 chan->move_state = L2CAP_MOVE_WAIT_PREPARE;
5049 /* Placeholder - uncomment when amp functions are available */
5050 /*amp_accept_physical(chan, req->dest_amp_id);*/
5051 result = L2CAP_MR_PEND;
5052 }
5053
5054send_move_response:
5055 l2cap_send_move_chan_rsp(chan, result);
5056
5057 l2cap_chan_unlock(chan);
5058
5059 return 0;
5060}
5061
5062static void l2cap_move_continue(struct l2cap_conn *conn, u16 icid, u16 result)
5063{
5064 struct l2cap_chan *chan;
5065 struct hci_chan *hchan = NULL;
5066
5067 chan = l2cap_get_chan_by_scid(conn, icid);
5068 if (!chan) {
5069 l2cap_send_move_chan_cfm_icid(conn, icid);
5070 return;
5071 }
5072
5073 __clear_chan_timer(chan);
5074 if (result == L2CAP_MR_PEND)
5075 __set_chan_timer(chan, L2CAP_MOVE_ERTX_TIMEOUT);
5076
5077 switch (chan->move_state) {
5078 case L2CAP_MOVE_WAIT_LOGICAL_COMP:
5079 /* Move confirm will be sent when logical link
5080 * is complete.
5081 */
5082 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
5083 break;
5084 case L2CAP_MOVE_WAIT_RSP_SUCCESS:
5085 if (result == L2CAP_MR_PEND) {
5086 break;
5087 } else if (test_bit(CONN_LOCAL_BUSY,
5088 &chan->conn_state)) {
5089 chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
5090 } else {
5091 /* Logical link is up or moving to BR/EDR,
5092 * proceed with move
5093 */
5094 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM_RSP;
5095 l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
5096 }
5097 break;
5098 case L2CAP_MOVE_WAIT_RSP:
5099 /* Moving to AMP */
5100 if (result == L2CAP_MR_SUCCESS) {
5101 /* Remote is ready, send confirm immediately
5102 * after logical link is ready
5103 */
5104 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
5105 } else {
5106 /* Both logical link and move success
5107 * are required to confirm
5108 */
5109 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_COMP;
5110 }
5111
5112 /* Placeholder - get hci_chan for logical link */
5113 if (!hchan) {
5114 /* Logical link not available */
5115 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5116 break;
5117 }
5118
5119 /* If the logical link is not yet connected, do not
5120 * send confirmation.
5121 */
5122 if (hchan->state != BT_CONNECTED)
5123 break;
5124
5125 /* Logical link is already ready to go */
5126
5127 chan->hs_hcon = hchan->conn;
5128 chan->hs_hcon->l2cap_data = chan->conn;
5129
5130 if (result == L2CAP_MR_SUCCESS) {
5131 /* Can confirm now */
5132 l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
5133 } else {
5134 /* Now only need move success
5135 * to confirm
5136 */
5137 chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
5138 }
5139
5140 l2cap_logical_cfm(chan, hchan, L2CAP_MR_SUCCESS);
5141 break;
5142 default:
5143 /* Any other amp move state means the move failed. */
5144 chan->move_id = chan->local_amp_id;
5145 l2cap_move_done(chan);
5146 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5147 }
5148
5149 l2cap_chan_unlock(chan);
5150}
5151
5152static void l2cap_move_fail(struct l2cap_conn *conn, u8 ident, u16 icid,
5153 u16 result)
5154{
5155 struct l2cap_chan *chan;
5156
5157 chan = l2cap_get_chan_by_ident(conn, ident);
5158 if (!chan) {
5159 /* Could not locate channel, icid is best guess */
5160 l2cap_send_move_chan_cfm_icid(conn, icid);
5161 return;
5162 }
5163
5164 __clear_chan_timer(chan);
5165
5166 if (chan->move_role == L2CAP_MOVE_ROLE_INITIATOR) {
5167 if (result == L2CAP_MR_COLLISION) {
5168 chan->move_role = L2CAP_MOVE_ROLE_RESPONDER;
5169 } else {
5170 /* Cleanup - cancel move */
5171 chan->move_id = chan->local_amp_id;
5172 l2cap_move_done(chan);
5173 }
5174 }
5175
5176 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5177
5178 l2cap_chan_unlock(chan);
5179}
5180
5181static int l2cap_move_channel_rsp(struct l2cap_conn *conn,
5182 struct l2cap_cmd_hdr *cmd,
5183 u16 cmd_len, void *data)
5184{
5185 struct l2cap_move_chan_rsp *rsp = data;
5186 u16 icid, result;
5187
5188 if (cmd_len != sizeof(*rsp))
5189 return -EPROTO;
5190
5191 icid = le16_to_cpu(rsp->icid);
5192 result = le16_to_cpu(rsp->result);
5193
5194 BT_DBG("icid 0x%4.4x, result 0x%4.4x", icid, result);
5195
5196 if (result == L2CAP_MR_SUCCESS || result == L2CAP_MR_PEND)
5197 l2cap_move_continue(conn, icid, result);
5198 else
5199 l2cap_move_fail(conn, cmd->ident, icid, result);
5200
5201 return 0;
5202}
5203
5204static int l2cap_move_channel_confirm(struct l2cap_conn *conn,
5205 struct l2cap_cmd_hdr *cmd,
5206 u16 cmd_len, void *data)
5207{
5208 struct l2cap_move_chan_cfm *cfm = data;
5209 struct l2cap_chan *chan;
5210 u16 icid, result;
5211
5212 if (cmd_len != sizeof(*cfm))
5213 return -EPROTO;
5214
5215 icid = le16_to_cpu(cfm->icid);
5216 result = le16_to_cpu(cfm->result);
5217
5218 BT_DBG("icid 0x%4.4x, result 0x%4.4x", icid, result);
5219
5220 chan = l2cap_get_chan_by_dcid(conn, icid);
5221 if (!chan) {
5222 /* Spec requires a response even if the icid was not found */
5223 l2cap_send_move_chan_cfm_rsp(conn, cmd->ident, icid);
5224 return 0;
5225 }
5226
5227 if (chan->move_state == L2CAP_MOVE_WAIT_CONFIRM) {
5228 if (result == L2CAP_MC_CONFIRMED) {
5229 chan->local_amp_id = chan->move_id;
5230 if (chan->local_amp_id == AMP_ID_BREDR)
5231 __release_logical_link(chan);
5232 } else {
5233 chan->move_id = chan->local_amp_id;
5234 }
5235
5236 l2cap_move_done(chan);
5237 }
5238
5239 l2cap_send_move_chan_cfm_rsp(conn, cmd->ident, icid);
5240
5241 l2cap_chan_unlock(chan);
5242
5243 return 0;
5244}
5245
5246static inline int l2cap_move_channel_confirm_rsp(struct l2cap_conn *conn,
5247 struct l2cap_cmd_hdr *cmd,
5248 u16 cmd_len, void *data)
5249{
5250 struct l2cap_move_chan_cfm_rsp *rsp = data;
5251 struct l2cap_chan *chan;
5252 u16 icid;
5253
5254 if (cmd_len != sizeof(*rsp))
5255 return -EPROTO;
5256
5257 icid = le16_to_cpu(rsp->icid);
5258
5259 BT_DBG("icid 0x%4.4x", icid);
5260
5261 chan = l2cap_get_chan_by_scid(conn, icid);
5262 if (!chan)
5263 return 0;
5264
5265 __clear_chan_timer(chan);
5266
5267 if (chan->move_state == L2CAP_MOVE_WAIT_CONFIRM_RSP) {
5268 chan->local_amp_id = chan->move_id;
5269
5270 if (chan->local_amp_id == AMP_ID_BREDR && chan->hs_hchan)
5271 __release_logical_link(chan);
5272
5273 l2cap_move_done(chan);
5274 }
5275
5276 l2cap_chan_unlock(chan);
5277
5278 return 0;
5279}
5280
5281static inline int l2cap_conn_param_update_req(struct l2cap_conn *conn,
5282 struct l2cap_cmd_hdr *cmd,
5283 u16 cmd_len, u8 *data)
5284{
5285 struct hci_conn *hcon = conn->hcon;
5286 struct l2cap_conn_param_update_req *req;
5287 struct l2cap_conn_param_update_rsp rsp;
5288 u16 min, max, latency, to_multiplier;
5289 int err;
5290
5291 if (hcon->role != HCI_ROLE_MASTER)
5292 return -EINVAL;
5293
5294 if (cmd_len != sizeof(struct l2cap_conn_param_update_req))
5295 return -EPROTO;
5296
5297 req = (struct l2cap_conn_param_update_req *) data;
5298 min = __le16_to_cpu(req->min);
5299 max = __le16_to_cpu(req->max);
5300 latency = __le16_to_cpu(req->latency);
5301 to_multiplier = __le16_to_cpu(req->to_multiplier);
5302
5303 BT_DBG("min 0x%4.4x max 0x%4.4x latency: 0x%4.4x Timeout: 0x%4.4x",
5304 min, max, latency, to_multiplier);
5305
5306 memset(&rsp, 0, sizeof(rsp));
5307
5308 err = hci_check_conn_params(min, max, latency, to_multiplier);
5309 if (err)
5310 rsp.result = cpu_to_le16(L2CAP_CONN_PARAM_REJECTED);
5311 else
5312 rsp.result = cpu_to_le16(L2CAP_CONN_PARAM_ACCEPTED);
5313
5314 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONN_PARAM_UPDATE_RSP,
5315 sizeof(rsp), &rsp);
5316
5317 if (!err) {
5318 u8 store_hint;
5319
5320 store_hint = hci_le_conn_update(hcon, min, max, latency,
5321 to_multiplier);
5322 mgmt_new_conn_param(hcon->hdev, &hcon->dst, hcon->dst_type,
5323 store_hint, min, max, latency,
5324 to_multiplier);
5325
5326 }
5327
5328 return 0;
5329}
5330
5331static int l2cap_le_connect_rsp(struct l2cap_conn *conn,
5332 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5333 u8 *data)
5334{
5335 struct l2cap_le_conn_rsp *rsp = (struct l2cap_le_conn_rsp *) data;
5336 struct hci_conn *hcon = conn->hcon;
5337 u16 dcid, mtu, mps, credits, result;
5338 struct l2cap_chan *chan;
5339 int err, sec_level;
5340
5341 if (cmd_len < sizeof(*rsp))
5342 return -EPROTO;
5343
5344 dcid = __le16_to_cpu(rsp->dcid);
5345 mtu = __le16_to_cpu(rsp->mtu);
5346 mps = __le16_to_cpu(rsp->mps);
5347 credits = __le16_to_cpu(rsp->credits);
5348 result = __le16_to_cpu(rsp->result);
5349
5350 if (result == L2CAP_CR_LE_SUCCESS && (mtu < 23 || mps < 23 ||
5351 dcid < L2CAP_CID_DYN_START ||
5352 dcid > L2CAP_CID_LE_DYN_END))
5353 return -EPROTO;
5354
5355 BT_DBG("dcid 0x%4.4x mtu %u mps %u credits %u result 0x%2.2x",
5356 dcid, mtu, mps, credits, result);
5357
5358 mutex_lock(&conn->chan_lock);
5359
5360 chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
5361 if (!chan) {
5362 err = -EBADSLT;
5363 goto unlock;
5364 }
5365
5366 err = 0;
5367
5368 l2cap_chan_lock(chan);
5369
5370 switch (result) {
5371 case L2CAP_CR_LE_SUCCESS:
5372 if (__l2cap_get_chan_by_dcid(conn, dcid)) {
5373 err = -EBADSLT;
5374 break;
5375 }
5376
5377 chan->ident = 0;
5378 chan->dcid = dcid;
5379 chan->omtu = mtu;
5380 chan->remote_mps = mps;
5381 chan->tx_credits = credits;
5382 l2cap_chan_ready(chan);
5383 break;
5384
5385 case L2CAP_CR_LE_AUTHENTICATION:
5386 case L2CAP_CR_LE_ENCRYPTION:
5387 /* If we already have MITM protection we can't do
5388 * anything.
5389 */
5390 if (hcon->sec_level > BT_SECURITY_MEDIUM) {
5391 l2cap_chan_del(chan, ECONNREFUSED);
5392 break;
5393 }
5394
5395 sec_level = hcon->sec_level + 1;
5396 if (chan->sec_level < sec_level)
5397 chan->sec_level = sec_level;
5398
5399 /* We'll need to send a new Connect Request */
5400 clear_bit(FLAG_LE_CONN_REQ_SENT, &chan->flags);
5401
5402 smp_conn_security(hcon, chan->sec_level);
5403 break;
5404
5405 default:
5406 l2cap_chan_del(chan, ECONNREFUSED);
5407 break;
5408 }
5409
5410 l2cap_chan_unlock(chan);
5411
5412unlock:
5413 mutex_unlock(&conn->chan_lock);
5414
5415 return err;
5416}
5417
5418static inline int l2cap_bredr_sig_cmd(struct l2cap_conn *conn,
5419 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5420 u8 *data)
5421{
5422 int err = 0;
5423
5424 switch (cmd->code) {
5425 case L2CAP_COMMAND_REJ:
5426 l2cap_command_rej(conn, cmd, cmd_len, data);
5427 break;
5428
5429 case L2CAP_CONN_REQ:
5430 err = l2cap_connect_req(conn, cmd, cmd_len, data);
5431 break;
5432
5433 case L2CAP_CONN_RSP:
5434 case L2CAP_CREATE_CHAN_RSP:
5435 l2cap_connect_create_rsp(conn, cmd, cmd_len, data);
5436 break;
5437
5438 case L2CAP_CONF_REQ:
5439 err = l2cap_config_req(conn, cmd, cmd_len, data);
5440 break;
5441
5442 case L2CAP_CONF_RSP:
5443 l2cap_config_rsp(conn, cmd, cmd_len, data);
5444 break;
5445
5446 case L2CAP_DISCONN_REQ:
5447 err = l2cap_disconnect_req(conn, cmd, cmd_len, data);
5448 break;
5449
5450 case L2CAP_DISCONN_RSP:
5451 l2cap_disconnect_rsp(conn, cmd, cmd_len, data);
5452 break;
5453
5454 case L2CAP_ECHO_REQ:
5455 l2cap_send_cmd(conn, cmd->ident, L2CAP_ECHO_RSP, cmd_len, data);
5456 break;
5457
5458 case L2CAP_ECHO_RSP:
5459 break;
5460
5461 case L2CAP_INFO_REQ:
5462 err = l2cap_information_req(conn, cmd, cmd_len, data);
5463 break;
5464
5465 case L2CAP_INFO_RSP:
5466 l2cap_information_rsp(conn, cmd, cmd_len, data);
5467 break;
5468
5469 case L2CAP_CREATE_CHAN_REQ:
5470 err = l2cap_create_channel_req(conn, cmd, cmd_len, data);
5471 break;
5472
5473 case L2CAP_MOVE_CHAN_REQ:
5474 err = l2cap_move_channel_req(conn, cmd, cmd_len, data);
5475 break;
5476
5477 case L2CAP_MOVE_CHAN_RSP:
5478 l2cap_move_channel_rsp(conn, cmd, cmd_len, data);
5479 break;
5480
5481 case L2CAP_MOVE_CHAN_CFM:
5482 err = l2cap_move_channel_confirm(conn, cmd, cmd_len, data);
5483 break;
5484
5485 case L2CAP_MOVE_CHAN_CFM_RSP:
5486 l2cap_move_channel_confirm_rsp(conn, cmd, cmd_len, data);
5487 break;
5488
5489 default:
5490 BT_ERR("Unknown BR/EDR signaling command 0x%2.2x", cmd->code);
5491 err = -EINVAL;
5492 break;
5493 }
5494
5495 return err;
5496}
5497
5498static int l2cap_le_connect_req(struct l2cap_conn *conn,
5499 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5500 u8 *data)
5501{
5502 struct l2cap_le_conn_req *req = (struct l2cap_le_conn_req *) data;
5503 struct l2cap_le_conn_rsp rsp;
5504 struct l2cap_chan *chan, *pchan;
5505 u16 dcid, scid, credits, mtu, mps;
5506 __le16 psm;
5507 u8 result;
5508
5509 if (cmd_len != sizeof(*req))
5510 return -EPROTO;
5511
5512 scid = __le16_to_cpu(req->scid);
5513 mtu = __le16_to_cpu(req->mtu);
5514 mps = __le16_to_cpu(req->mps);
5515 psm = req->psm;
5516 dcid = 0;
5517 credits = 0;
5518
5519 if (mtu < 23 || mps < 23)
5520 return -EPROTO;
5521
5522 BT_DBG("psm 0x%2.2x scid 0x%4.4x mtu %u mps %u", __le16_to_cpu(psm),
5523 scid, mtu, mps);
5524
5525 /* Check if we have socket listening on psm */
5526 pchan = l2cap_global_chan_by_psm(BT_LISTEN, psm, &conn->hcon->src,
5527 &conn->hcon->dst, LE_LINK);
5528 if (!pchan) {
5529 result = L2CAP_CR_LE_BAD_PSM;
5530 chan = NULL;
5531 goto response;
5532 }
5533
5534 mutex_lock(&conn->chan_lock);
5535 l2cap_chan_lock(pchan);
5536
5537 if (!smp_sufficient_security(conn->hcon, pchan->sec_level,
5538 SMP_ALLOW_STK)) {
5539 result = L2CAP_CR_LE_AUTHENTICATION;
5540 chan = NULL;
5541 goto response_unlock;
5542 }
5543
5544 /* Check for valid dynamic CID range */
5545 if (scid < L2CAP_CID_DYN_START || scid > L2CAP_CID_LE_DYN_END) {
5546 result = L2CAP_CR_LE_INVALID_SCID;
5547 chan = NULL;
5548 goto response_unlock;
5549 }
5550
5551 /* Check if we already have channel with that dcid */
5552 if (__l2cap_get_chan_by_dcid(conn, scid)) {
5553 result = L2CAP_CR_LE_SCID_IN_USE;
5554 chan = NULL;
5555 goto response_unlock;
5556 }
5557
5558 chan = pchan->ops->new_connection(pchan);
5559 if (!chan) {
5560 result = L2CAP_CR_LE_NO_MEM;
5561 goto response_unlock;
5562 }
5563
5564 bacpy(&chan->src, &conn->hcon->src);
5565 bacpy(&chan->dst, &conn->hcon->dst);
5566 chan->src_type = bdaddr_src_type(conn->hcon);
5567 chan->dst_type = bdaddr_dst_type(conn->hcon);
5568 chan->psm = psm;
5569 chan->dcid = scid;
5570 chan->omtu = mtu;
5571 chan->remote_mps = mps;
5572
5573 __l2cap_chan_add(conn, chan);
5574
5575 l2cap_le_flowctl_init(chan, __le16_to_cpu(req->credits));
5576
5577 dcid = chan->scid;
5578 credits = chan->rx_credits;
5579
5580 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
5581
5582 chan->ident = cmd->ident;
5583
5584 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
5585 l2cap_state_change(chan, BT_CONNECT2);
5586 /* The following result value is actually not defined
5587 * for LE CoC but we use it to let the function know
5588 * that it should bail out after doing its cleanup
5589 * instead of sending a response.
5590 */
5591 result = L2CAP_CR_PEND;
5592 chan->ops->defer(chan);
5593 } else {
5594 l2cap_chan_ready(chan);
5595 result = L2CAP_CR_LE_SUCCESS;
5596 }
5597
5598response_unlock:
5599 l2cap_chan_unlock(pchan);
5600 mutex_unlock(&conn->chan_lock);
5601 l2cap_chan_put(pchan);
5602
5603 if (result == L2CAP_CR_PEND)
5604 return 0;
5605
5606response:
5607 if (chan) {
5608 rsp.mtu = cpu_to_le16(chan->imtu);
5609 rsp.mps = cpu_to_le16(chan->mps);
5610 } else {
5611 rsp.mtu = 0;
5612 rsp.mps = 0;
5613 }
5614
5615 rsp.dcid = cpu_to_le16(dcid);
5616 rsp.credits = cpu_to_le16(credits);
5617 rsp.result = cpu_to_le16(result);
5618
5619 l2cap_send_cmd(conn, cmd->ident, L2CAP_LE_CONN_RSP, sizeof(rsp), &rsp);
5620
5621 return 0;
5622}
5623
5624static inline int l2cap_le_credits(struct l2cap_conn *conn,
5625 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5626 u8 *data)
5627{
5628 struct l2cap_le_credits *pkt;
5629 struct l2cap_chan *chan;
5630 u16 cid, credits, max_credits;
5631
5632 if (cmd_len != sizeof(*pkt))
5633 return -EPROTO;
5634
5635 pkt = (struct l2cap_le_credits *) data;
5636 cid = __le16_to_cpu(pkt->cid);
5637 credits = __le16_to_cpu(pkt->credits);
5638
5639 BT_DBG("cid 0x%4.4x credits 0x%4.4x", cid, credits);
5640
5641 chan = l2cap_get_chan_by_dcid(conn, cid);
5642 if (!chan)
5643 return -EBADSLT;
5644
5645 max_credits = LE_FLOWCTL_MAX_CREDITS - chan->tx_credits;
5646 if (credits > max_credits) {
5647 BT_ERR("LE credits overflow");
5648 l2cap_send_disconn_req(chan, ECONNRESET);
5649 l2cap_chan_unlock(chan);
5650
5651 /* Return 0 so that we don't trigger an unnecessary
5652 * command reject packet.
5653 */
5654 return 0;
5655 }
5656
5657 chan->tx_credits += credits;
5658
5659 /* Resume sending */
5660 l2cap_le_flowctl_send(chan);
5661
5662 if (chan->tx_credits)
5663 chan->ops->resume(chan);
5664
5665 l2cap_chan_unlock(chan);
5666
5667 return 0;
5668}
5669
5670static inline int l2cap_le_command_rej(struct l2cap_conn *conn,
5671 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5672 u8 *data)
5673{
5674 struct l2cap_cmd_rej_unk *rej = (struct l2cap_cmd_rej_unk *) data;
5675 struct l2cap_chan *chan;
5676
5677 if (cmd_len < sizeof(*rej))
5678 return -EPROTO;
5679
5680 mutex_lock(&conn->chan_lock);
5681
5682 chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
5683 if (!chan)
5684 goto done;
5685
5686 l2cap_chan_lock(chan);
5687 l2cap_chan_del(chan, ECONNREFUSED);
5688 l2cap_chan_unlock(chan);
5689
5690done:
5691 mutex_unlock(&conn->chan_lock);
5692 return 0;
5693}
5694
5695static inline int l2cap_le_sig_cmd(struct l2cap_conn *conn,
5696 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5697 u8 *data)
5698{
5699 int err = 0;
5700
5701 switch (cmd->code) {
5702 case L2CAP_COMMAND_REJ:
5703 l2cap_le_command_rej(conn, cmd, cmd_len, data);
5704 break;
5705
5706 case L2CAP_CONN_PARAM_UPDATE_REQ:
5707 err = l2cap_conn_param_update_req(conn, cmd, cmd_len, data);
5708 break;
5709
5710 case L2CAP_CONN_PARAM_UPDATE_RSP:
5711 break;
5712
5713 case L2CAP_LE_CONN_RSP:
5714 l2cap_le_connect_rsp(conn, cmd, cmd_len, data);
5715 break;
5716
5717 case L2CAP_LE_CONN_REQ:
5718 err = l2cap_le_connect_req(conn, cmd, cmd_len, data);
5719 break;
5720
5721 case L2CAP_LE_CREDITS:
5722 err = l2cap_le_credits(conn, cmd, cmd_len, data);
5723 break;
5724
5725 case L2CAP_DISCONN_REQ:
5726 err = l2cap_disconnect_req(conn, cmd, cmd_len, data);
5727 break;
5728
5729 case L2CAP_DISCONN_RSP:
5730 l2cap_disconnect_rsp(conn, cmd, cmd_len, data);
5731 break;
5732
5733 default:
5734 BT_ERR("Unknown LE signaling command 0x%2.2x", cmd->code);
5735 err = -EINVAL;
5736 break;
5737 }
5738
5739 return err;
5740}
5741
5742static inline void l2cap_le_sig_channel(struct l2cap_conn *conn,
5743 struct sk_buff *skb)
5744{
5745 struct hci_conn *hcon = conn->hcon;
5746 struct l2cap_cmd_hdr *cmd;
5747 u16 len;
5748 int err;
5749
5750 if (hcon->type != LE_LINK)
5751 goto drop;
5752
5753 if (skb->len < L2CAP_CMD_HDR_SIZE)
5754 goto drop;
5755
5756 cmd = (void *) skb->data;
5757 skb_pull(skb, L2CAP_CMD_HDR_SIZE);
5758
5759 len = le16_to_cpu(cmd->len);
5760
5761 BT_DBG("code 0x%2.2x len %d id 0x%2.2x", cmd->code, len, cmd->ident);
5762
5763 if (len != skb->len || !cmd->ident) {
5764 BT_DBG("corrupted command");
5765 goto drop;
5766 }
5767
5768 err = l2cap_le_sig_cmd(conn, cmd, len, skb->data);
5769 if (err) {
5770 struct l2cap_cmd_rej_unk rej;
5771
5772 BT_ERR("Wrong link type (%d)", err);
5773
5774 rej.reason = cpu_to_le16(L2CAP_REJ_NOT_UNDERSTOOD);
5775 l2cap_send_cmd(conn, cmd->ident, L2CAP_COMMAND_REJ,
5776 sizeof(rej), &rej);
5777 }
5778
5779drop:
5780 kfree_skb(skb);
5781}
5782
5783static inline void l2cap_sig_channel(struct l2cap_conn *conn,
5784 struct sk_buff *skb)
5785{
5786 struct hci_conn *hcon = conn->hcon;
5787 u8 *data = skb->data;
5788 int len = skb->len;
5789 struct l2cap_cmd_hdr cmd;
5790 int err;
5791
5792 l2cap_raw_recv(conn, skb);
5793
5794 if (hcon->type != ACL_LINK)
5795 goto drop;
5796
5797 while (len >= L2CAP_CMD_HDR_SIZE) {
5798 u16 cmd_len;
5799 memcpy(&cmd, data, L2CAP_CMD_HDR_SIZE);
5800 data += L2CAP_CMD_HDR_SIZE;
5801 len -= L2CAP_CMD_HDR_SIZE;
5802
5803 cmd_len = le16_to_cpu(cmd.len);
5804
5805 BT_DBG("code 0x%2.2x len %d id 0x%2.2x", cmd.code, cmd_len,
5806 cmd.ident);
5807
5808 if (cmd_len > len || !cmd.ident) {
5809 BT_DBG("corrupted command");
5810 break;
5811 }
5812
5813 err = l2cap_bredr_sig_cmd(conn, &cmd, cmd_len, data);
5814 if (err) {
5815 struct l2cap_cmd_rej_unk rej;
5816
5817 BT_ERR("Wrong link type (%d)", err);
5818
5819 rej.reason = cpu_to_le16(L2CAP_REJ_NOT_UNDERSTOOD);
5820 l2cap_send_cmd(conn, cmd.ident, L2CAP_COMMAND_REJ,
5821 sizeof(rej), &rej);
5822 }
5823
5824 data += cmd_len;
5825 len -= cmd_len;
5826 }
5827
5828drop:
5829 kfree_skb(skb);
5830}
5831
5832static int l2cap_check_fcs(struct l2cap_chan *chan, struct sk_buff *skb)
5833{
5834 u16 our_fcs, rcv_fcs;
5835 int hdr_size;
5836
5837 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
5838 hdr_size = L2CAP_EXT_HDR_SIZE;
5839 else
5840 hdr_size = L2CAP_ENH_HDR_SIZE;
5841
5842 if (chan->fcs == L2CAP_FCS_CRC16) {
5843 skb_trim(skb, skb->len - L2CAP_FCS_SIZE);
5844 rcv_fcs = get_unaligned_le16(skb->data + skb->len);
5845 our_fcs = crc16(0, skb->data - hdr_size, skb->len + hdr_size);
5846
5847 if (our_fcs != rcv_fcs)
5848 return -EBADMSG;
5849 }
5850 return 0;
5851}
5852
5853static void l2cap_send_i_or_rr_or_rnr(struct l2cap_chan *chan)
5854{
5855 struct l2cap_ctrl control;
5856
5857 BT_DBG("chan %p", chan);
5858
5859 memset(&control, 0, sizeof(control));
5860 control.sframe = 1;
5861 control.final = 1;
5862 control.reqseq = chan->buffer_seq;
5863 set_bit(CONN_SEND_FBIT, &chan->conn_state);
5864
5865 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
5866 control.super = L2CAP_SUPER_RNR;
5867 l2cap_send_sframe(chan, &control);
5868 }
5869
5870 if (test_and_clear_bit(CONN_REMOTE_BUSY, &chan->conn_state) &&
5871 chan->unacked_frames > 0)
5872 __set_retrans_timer(chan);
5873
5874 /* Send pending iframes */
5875 l2cap_ertm_send(chan);
5876
5877 if (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state) &&
5878 test_bit(CONN_SEND_FBIT, &chan->conn_state)) {
5879 /* F-bit wasn't sent in an s-frame or i-frame yet, so
5880 * send it now.
5881 */
5882 control.super = L2CAP_SUPER_RR;
5883 l2cap_send_sframe(chan, &control);
5884 }
5885}
5886
5887static void append_skb_frag(struct sk_buff *skb, struct sk_buff *new_frag,
5888 struct sk_buff **last_frag)
5889{
5890 /* skb->len reflects data in skb as well as all fragments
5891 * skb->data_len reflects only data in fragments
5892 */
5893 if (!skb_has_frag_list(skb))
5894 skb_shinfo(skb)->frag_list = new_frag;
5895
5896 new_frag->next = NULL;
5897
5898 (*last_frag)->next = new_frag;
5899 *last_frag = new_frag;
5900
5901 skb->len += new_frag->len;
5902 skb->data_len += new_frag->len;
5903 skb->truesize += new_frag->truesize;
5904}
5905
5906static int l2cap_reassemble_sdu(struct l2cap_chan *chan, struct sk_buff *skb,
5907 struct l2cap_ctrl *control)
5908{
5909 int err = -EINVAL;
5910
5911 switch (control->sar) {
5912 case L2CAP_SAR_UNSEGMENTED:
5913 if (chan->sdu)
5914 break;
5915
5916 err = chan->ops->recv(chan, skb);
5917 break;
5918
5919 case L2CAP_SAR_START:
5920 if (chan->sdu)
5921 break;
5922
5923 if (!pskb_may_pull(skb, L2CAP_SDULEN_SIZE))
5924 break;
5925
5926 chan->sdu_len = get_unaligned_le16(skb->data);
5927 skb_pull(skb, L2CAP_SDULEN_SIZE);
5928
5929 if (chan->sdu_len > chan->imtu) {
5930 err = -EMSGSIZE;
5931 break;
5932 }
5933
5934 if (skb->len >= chan->sdu_len)
5935 break;
5936
5937 chan->sdu = skb;
5938 chan->sdu_last_frag = skb;
5939
5940 skb = NULL;
5941 err = 0;
5942 break;
5943
5944 case L2CAP_SAR_CONTINUE:
5945 if (!chan->sdu)
5946 break;
5947
5948 append_skb_frag(chan->sdu, skb,
5949 &chan->sdu_last_frag);
5950 skb = NULL;
5951
5952 if (chan->sdu->len >= chan->sdu_len)
5953 break;
5954
5955 err = 0;
5956 break;
5957
5958 case L2CAP_SAR_END:
5959 if (!chan->sdu)
5960 break;
5961
5962 append_skb_frag(chan->sdu, skb,
5963 &chan->sdu_last_frag);
5964 skb = NULL;
5965
5966 if (chan->sdu->len != chan->sdu_len)
5967 break;
5968
5969 err = chan->ops->recv(chan, chan->sdu);
5970
5971 if (!err) {
5972 /* Reassembly complete */
5973 chan->sdu = NULL;
5974 chan->sdu_last_frag = NULL;
5975 chan->sdu_len = 0;
5976 }
5977 break;
5978 }
5979
5980 if (err) {
5981 kfree_skb(skb);
5982 kfree_skb(chan->sdu);
5983 chan->sdu = NULL;
5984 chan->sdu_last_frag = NULL;
5985 chan->sdu_len = 0;
5986 }
5987
5988 return err;
5989}
5990
5991static int l2cap_resegment(struct l2cap_chan *chan)
5992{
5993 /* Placeholder */
5994 return 0;
5995}
5996
5997void l2cap_chan_busy(struct l2cap_chan *chan, int busy)
5998{
5999 u8 event;
6000
6001 if (chan->mode != L2CAP_MODE_ERTM)
6002 return;
6003
6004 event = busy ? L2CAP_EV_LOCAL_BUSY_DETECTED : L2CAP_EV_LOCAL_BUSY_CLEAR;
6005 l2cap_tx(chan, NULL, NULL, event);
6006}
6007
6008static int l2cap_rx_queued_iframes(struct l2cap_chan *chan)
6009{
6010 int err = 0;
6011 /* Pass sequential frames to l2cap_reassemble_sdu()
6012 * until a gap is encountered.
6013 */
6014
6015 BT_DBG("chan %p", chan);
6016
6017 while (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
6018 struct sk_buff *skb;
6019 BT_DBG("Searching for skb with txseq %d (queue len %d)",
6020 chan->buffer_seq, skb_queue_len(&chan->srej_q));
6021
6022 skb = l2cap_ertm_seq_in_queue(&chan->srej_q, chan->buffer_seq);
6023
6024 if (!skb)
6025 break;
6026
6027 skb_unlink(skb, &chan->srej_q);
6028 chan->buffer_seq = __next_seq(chan, chan->buffer_seq);
6029 err = l2cap_reassemble_sdu(chan, skb, &bt_cb(skb)->l2cap);
6030 if (err)
6031 break;
6032 }
6033
6034 if (skb_queue_empty(&chan->srej_q)) {
6035 chan->rx_state = L2CAP_RX_STATE_RECV;
6036 l2cap_send_ack(chan);
6037 }
6038
6039 return err;
6040}
6041
6042static void l2cap_handle_srej(struct l2cap_chan *chan,
6043 struct l2cap_ctrl *control)
6044{
6045 struct sk_buff *skb;
6046
6047 BT_DBG("chan %p, control %p", chan, control);
6048
6049 if (control->reqseq == chan->next_tx_seq) {
6050 BT_DBG("Invalid reqseq %d, disconnecting", control->reqseq);
6051 l2cap_send_disconn_req(chan, ECONNRESET);
6052 return;
6053 }
6054
6055 skb = l2cap_ertm_seq_in_queue(&chan->tx_q, control->reqseq);
6056
6057 if (skb == NULL) {
6058 BT_DBG("Seq %d not available for retransmission",
6059 control->reqseq);
6060 return;
6061 }
6062
6063 if (chan->max_tx != 0 && bt_cb(skb)->l2cap.retries >= chan->max_tx) {
6064 BT_DBG("Retry limit exceeded (%d)", chan->max_tx);
6065 l2cap_send_disconn_req(chan, ECONNRESET);
6066 return;
6067 }
6068
6069 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6070
6071 if (control->poll) {
6072 l2cap_pass_to_tx(chan, control);
6073
6074 set_bit(CONN_SEND_FBIT, &chan->conn_state);
6075 l2cap_retransmit(chan, control);
6076 l2cap_ertm_send(chan);
6077
6078 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F) {
6079 set_bit(CONN_SREJ_ACT, &chan->conn_state);
6080 chan->srej_save_reqseq = control->reqseq;
6081 }
6082 } else {
6083 l2cap_pass_to_tx_fbit(chan, control);
6084
6085 if (control->final) {
6086 if (chan->srej_save_reqseq != control->reqseq ||
6087 !test_and_clear_bit(CONN_SREJ_ACT,
6088 &chan->conn_state))
6089 l2cap_retransmit(chan, control);
6090 } else {
6091 l2cap_retransmit(chan, control);
6092 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F) {
6093 set_bit(CONN_SREJ_ACT, &chan->conn_state);
6094 chan->srej_save_reqseq = control->reqseq;
6095 }
6096 }
6097 }
6098}
6099
6100static void l2cap_handle_rej(struct l2cap_chan *chan,
6101 struct l2cap_ctrl *control)
6102{
6103 struct sk_buff *skb;
6104
6105 BT_DBG("chan %p, control %p", chan, control);
6106
6107 if (control->reqseq == chan->next_tx_seq) {
6108 BT_DBG("Invalid reqseq %d, disconnecting", control->reqseq);
6109 l2cap_send_disconn_req(chan, ECONNRESET);
6110 return;
6111 }
6112
6113 skb = l2cap_ertm_seq_in_queue(&chan->tx_q, control->reqseq);
6114
6115 if (chan->max_tx && skb &&
6116 bt_cb(skb)->l2cap.retries >= chan->max_tx) {
6117 BT_DBG("Retry limit exceeded (%d)", chan->max_tx);
6118 l2cap_send_disconn_req(chan, ECONNRESET);
6119 return;
6120 }
6121
6122 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6123
6124 l2cap_pass_to_tx(chan, control);
6125
6126 if (control->final) {
6127 if (!test_and_clear_bit(CONN_REJ_ACT, &chan->conn_state))
6128 l2cap_retransmit_all(chan, control);
6129 } else {
6130 l2cap_retransmit_all(chan, control);
6131 l2cap_ertm_send(chan);
6132 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F)
6133 set_bit(CONN_REJ_ACT, &chan->conn_state);
6134 }
6135}
6136
6137static u8 l2cap_classify_txseq(struct l2cap_chan *chan, u16 txseq)
6138{
6139 BT_DBG("chan %p, txseq %d", chan, txseq);
6140
6141 BT_DBG("last_acked_seq %d, expected_tx_seq %d", chan->last_acked_seq,
6142 chan->expected_tx_seq);
6143
6144 if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) {
6145 if (__seq_offset(chan, txseq, chan->last_acked_seq) >=
6146 chan->tx_win) {
6147 /* See notes below regarding "double poll" and
6148 * invalid packets.
6149 */
6150 if (chan->tx_win <= ((chan->tx_win_max + 1) >> 1)) {
6151 BT_DBG("Invalid/Ignore - after SREJ");
6152 return L2CAP_TXSEQ_INVALID_IGNORE;
6153 } else {
6154 BT_DBG("Invalid - in window after SREJ sent");
6155 return L2CAP_TXSEQ_INVALID;
6156 }
6157 }
6158
6159 if (chan->srej_list.head == txseq) {
6160 BT_DBG("Expected SREJ");
6161 return L2CAP_TXSEQ_EXPECTED_SREJ;
6162 }
6163
6164 if (l2cap_ertm_seq_in_queue(&chan->srej_q, txseq)) {
6165 BT_DBG("Duplicate SREJ - txseq already stored");
6166 return L2CAP_TXSEQ_DUPLICATE_SREJ;
6167 }
6168
6169 if (l2cap_seq_list_contains(&chan->srej_list, txseq)) {
6170 BT_DBG("Unexpected SREJ - not requested");
6171 return L2CAP_TXSEQ_UNEXPECTED_SREJ;
6172 }
6173 }
6174
6175 if (chan->expected_tx_seq == txseq) {
6176 if (__seq_offset(chan, txseq, chan->last_acked_seq) >=
6177 chan->tx_win) {
6178 BT_DBG("Invalid - txseq outside tx window");
6179 return L2CAP_TXSEQ_INVALID;
6180 } else {
6181 BT_DBG("Expected");
6182 return L2CAP_TXSEQ_EXPECTED;
6183 }
6184 }
6185
6186 if (__seq_offset(chan, txseq, chan->last_acked_seq) <
6187 __seq_offset(chan, chan->expected_tx_seq, chan->last_acked_seq)) {
6188 BT_DBG("Duplicate - expected_tx_seq later than txseq");
6189 return L2CAP_TXSEQ_DUPLICATE;
6190 }
6191
6192 if (__seq_offset(chan, txseq, chan->last_acked_seq) >= chan->tx_win) {
6193 /* A source of invalid packets is a "double poll" condition,
6194 * where delays cause us to send multiple poll packets. If
6195 * the remote stack receives and processes both polls,
6196 * sequence numbers can wrap around in such a way that a
6197 * resent frame has a sequence number that looks like new data
6198 * with a sequence gap. This would trigger an erroneous SREJ
6199 * request.
6200 *
6201 * Fortunately, this is impossible with a tx window that's
6202 * less than half of the maximum sequence number, which allows
6203 * invalid frames to be safely ignored.
6204 *
6205 * With tx window sizes greater than half of the tx window
6206 * maximum, the frame is invalid and cannot be ignored. This
6207 * causes a disconnect.
6208 */
6209
6210 if (chan->tx_win <= ((chan->tx_win_max + 1) >> 1)) {
6211 BT_DBG("Invalid/Ignore - txseq outside tx window");
6212 return L2CAP_TXSEQ_INVALID_IGNORE;
6213 } else {
6214 BT_DBG("Invalid - txseq outside tx window");
6215 return L2CAP_TXSEQ_INVALID;
6216 }
6217 } else {
6218 BT_DBG("Unexpected - txseq indicates missing frames");
6219 return L2CAP_TXSEQ_UNEXPECTED;
6220 }
6221}
6222
6223static int l2cap_rx_state_recv(struct l2cap_chan *chan,
6224 struct l2cap_ctrl *control,
6225 struct sk_buff *skb, u8 event)
6226{
6227 int err = 0;
6228 bool skb_in_use = false;
6229
6230 BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
6231 event);
6232
6233 switch (event) {
6234 case L2CAP_EV_RECV_IFRAME:
6235 switch (l2cap_classify_txseq(chan, control->txseq)) {
6236 case L2CAP_TXSEQ_EXPECTED:
6237 l2cap_pass_to_tx(chan, control);
6238
6239 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
6240 BT_DBG("Busy, discarding expected seq %d",
6241 control->txseq);
6242 break;
6243 }
6244
6245 chan->expected_tx_seq = __next_seq(chan,
6246 control->txseq);
6247
6248 chan->buffer_seq = chan->expected_tx_seq;
6249 skb_in_use = true;
6250
6251 err = l2cap_reassemble_sdu(chan, skb, control);
6252 if (err)
6253 break;
6254
6255 if (control->final) {
6256 if (!test_and_clear_bit(CONN_REJ_ACT,
6257 &chan->conn_state)) {
6258 control->final = 0;
6259 l2cap_retransmit_all(chan, control);
6260 l2cap_ertm_send(chan);
6261 }
6262 }
6263
6264 if (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state))
6265 l2cap_send_ack(chan);
6266 break;
6267 case L2CAP_TXSEQ_UNEXPECTED:
6268 l2cap_pass_to_tx(chan, control);
6269
6270 /* Can't issue SREJ frames in the local busy state.
6271 * Drop this frame, it will be seen as missing
6272 * when local busy is exited.
6273 */
6274 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
6275 BT_DBG("Busy, discarding unexpected seq %d",
6276 control->txseq);
6277 break;
6278 }
6279
6280 /* There was a gap in the sequence, so an SREJ
6281 * must be sent for each missing frame. The
6282 * current frame is stored for later use.
6283 */
6284 skb_queue_tail(&chan->srej_q, skb);
6285 skb_in_use = true;
6286 BT_DBG("Queued %p (queue len %d)", skb,
6287 skb_queue_len(&chan->srej_q));
6288
6289 clear_bit(CONN_SREJ_ACT, &chan->conn_state);
6290 l2cap_seq_list_clear(&chan->srej_list);
6291 l2cap_send_srej(chan, control->txseq);
6292
6293 chan->rx_state = L2CAP_RX_STATE_SREJ_SENT;
6294 break;
6295 case L2CAP_TXSEQ_DUPLICATE:
6296 l2cap_pass_to_tx(chan, control);
6297 break;
6298 case L2CAP_TXSEQ_INVALID_IGNORE:
6299 break;
6300 case L2CAP_TXSEQ_INVALID:
6301 default:
6302 l2cap_send_disconn_req(chan, ECONNRESET);
6303 break;
6304 }
6305 break;
6306 case L2CAP_EV_RECV_RR:
6307 l2cap_pass_to_tx(chan, control);
6308 if (control->final) {
6309 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6310
6311 if (!test_and_clear_bit(CONN_REJ_ACT, &chan->conn_state) &&
6312 !__chan_is_moving(chan)) {
6313 control->final = 0;
6314 l2cap_retransmit_all(chan, control);
6315 }
6316
6317 l2cap_ertm_send(chan);
6318 } else if (control->poll) {
6319 l2cap_send_i_or_rr_or_rnr(chan);
6320 } else {
6321 if (test_and_clear_bit(CONN_REMOTE_BUSY,
6322 &chan->conn_state) &&
6323 chan->unacked_frames)
6324 __set_retrans_timer(chan);
6325
6326 l2cap_ertm_send(chan);
6327 }
6328 break;
6329 case L2CAP_EV_RECV_RNR:
6330 set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6331 l2cap_pass_to_tx(chan, control);
6332 if (control && control->poll) {
6333 set_bit(CONN_SEND_FBIT, &chan->conn_state);
6334 l2cap_send_rr_or_rnr(chan, 0);
6335 }
6336 __clear_retrans_timer(chan);
6337 l2cap_seq_list_clear(&chan->retrans_list);
6338 break;
6339 case L2CAP_EV_RECV_REJ:
6340 l2cap_handle_rej(chan, control);
6341 break;
6342 case L2CAP_EV_RECV_SREJ:
6343 l2cap_handle_srej(chan, control);
6344 break;
6345 default:
6346 break;
6347 }
6348
6349 if (skb && !skb_in_use) {
6350 BT_DBG("Freeing %p", skb);
6351 kfree_skb(skb);
6352 }
6353
6354 return err;
6355}
6356
6357static int l2cap_rx_state_srej_sent(struct l2cap_chan *chan,
6358 struct l2cap_ctrl *control,
6359 struct sk_buff *skb, u8 event)
6360{
6361 int err = 0;
6362 u16 txseq = control->txseq;
6363 bool skb_in_use = false;
6364
6365 BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
6366 event);
6367
6368 switch (event) {
6369 case L2CAP_EV_RECV_IFRAME:
6370 switch (l2cap_classify_txseq(chan, txseq)) {
6371 case L2CAP_TXSEQ_EXPECTED:
6372 /* Keep frame for reassembly later */
6373 l2cap_pass_to_tx(chan, control);
6374 skb_queue_tail(&chan->srej_q, skb);
6375 skb_in_use = true;
6376 BT_DBG("Queued %p (queue len %d)", skb,
6377 skb_queue_len(&chan->srej_q));
6378
6379 chan->expected_tx_seq = __next_seq(chan, txseq);
6380 break;
6381 case L2CAP_TXSEQ_EXPECTED_SREJ:
6382 l2cap_seq_list_pop(&chan->srej_list);
6383
6384 l2cap_pass_to_tx(chan, control);
6385 skb_queue_tail(&chan->srej_q, skb);
6386 skb_in_use = true;
6387 BT_DBG("Queued %p (queue len %d)", skb,
6388 skb_queue_len(&chan->srej_q));
6389
6390 err = l2cap_rx_queued_iframes(chan);
6391 if (err)
6392 break;
6393
6394 break;
6395 case L2CAP_TXSEQ_UNEXPECTED:
6396 /* Got a frame that can't be reassembled yet.
6397 * Save it for later, and send SREJs to cover
6398 * the missing frames.
6399 */
6400 skb_queue_tail(&chan->srej_q, skb);
6401 skb_in_use = true;
6402 BT_DBG("Queued %p (queue len %d)", skb,
6403 skb_queue_len(&chan->srej_q));
6404
6405 l2cap_pass_to_tx(chan, control);
6406 l2cap_send_srej(chan, control->txseq);
6407 break;
6408 case L2CAP_TXSEQ_UNEXPECTED_SREJ:
6409 /* This frame was requested with an SREJ, but
6410 * some expected retransmitted frames are
6411 * missing. Request retransmission of missing
6412 * SREJ'd frames.
6413 */
6414 skb_queue_tail(&chan->srej_q, skb);
6415 skb_in_use = true;
6416 BT_DBG("Queued %p (queue len %d)", skb,
6417 skb_queue_len(&chan->srej_q));
6418
6419 l2cap_pass_to_tx(chan, control);
6420 l2cap_send_srej_list(chan, control->txseq);
6421 break;
6422 case L2CAP_TXSEQ_DUPLICATE_SREJ:
6423 /* We've already queued this frame. Drop this copy. */
6424 l2cap_pass_to_tx(chan, control);
6425 break;
6426 case L2CAP_TXSEQ_DUPLICATE:
6427 /* Expecting a later sequence number, so this frame
6428 * was already received. Ignore it completely.
6429 */
6430 break;
6431 case L2CAP_TXSEQ_INVALID_IGNORE:
6432 break;
6433 case L2CAP_TXSEQ_INVALID:
6434 default:
6435 l2cap_send_disconn_req(chan, ECONNRESET);
6436 break;
6437 }
6438 break;
6439 case L2CAP_EV_RECV_RR:
6440 l2cap_pass_to_tx(chan, control);
6441 if (control->final) {
6442 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6443
6444 if (!test_and_clear_bit(CONN_REJ_ACT,
6445 &chan->conn_state)) {
6446 control->final = 0;
6447 l2cap_retransmit_all(chan, control);
6448 }
6449
6450 l2cap_ertm_send(chan);
6451 } else if (control->poll) {
6452 if (test_and_clear_bit(CONN_REMOTE_BUSY,
6453 &chan->conn_state) &&
6454 chan->unacked_frames) {
6455 __set_retrans_timer(chan);
6456 }
6457
6458 set_bit(CONN_SEND_FBIT, &chan->conn_state);
6459 l2cap_send_srej_tail(chan);
6460 } else {
6461 if (test_and_clear_bit(CONN_REMOTE_BUSY,
6462 &chan->conn_state) &&
6463 chan->unacked_frames)
6464 __set_retrans_timer(chan);
6465
6466 l2cap_send_ack(chan);
6467 }
6468 break;
6469 case L2CAP_EV_RECV_RNR:
6470 set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6471 l2cap_pass_to_tx(chan, control);
6472 if (control->poll) {
6473 l2cap_send_srej_tail(chan);
6474 } else {
6475 struct l2cap_ctrl rr_control;
6476 memset(&rr_control, 0, sizeof(rr_control));
6477 rr_control.sframe = 1;
6478 rr_control.super = L2CAP_SUPER_RR;
6479 rr_control.reqseq = chan->buffer_seq;
6480 l2cap_send_sframe(chan, &rr_control);
6481 }
6482
6483 break;
6484 case L2CAP_EV_RECV_REJ:
6485 l2cap_handle_rej(chan, control);
6486 break;
6487 case L2CAP_EV_RECV_SREJ:
6488 l2cap_handle_srej(chan, control);
6489 break;
6490 }
6491
6492 if (skb && !skb_in_use) {
6493 BT_DBG("Freeing %p", skb);
6494 kfree_skb(skb);
6495 }
6496
6497 return err;
6498}
6499
6500static int l2cap_finish_move(struct l2cap_chan *chan)
6501{
6502 BT_DBG("chan %p", chan);
6503
6504 chan->rx_state = L2CAP_RX_STATE_RECV;
6505
6506 if (chan->hs_hcon)
6507 chan->conn->mtu = chan->hs_hcon->hdev->block_mtu;
6508 else
6509 chan->conn->mtu = chan->conn->hcon->hdev->acl_mtu;
6510
6511 return l2cap_resegment(chan);
6512}
6513
6514static int l2cap_rx_state_wait_p(struct l2cap_chan *chan,
6515 struct l2cap_ctrl *control,
6516 struct sk_buff *skb, u8 event)
6517{
6518 int err;
6519
6520 BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
6521 event);
6522
6523 if (!control->poll)
6524 return -EPROTO;
6525
6526 l2cap_process_reqseq(chan, control->reqseq);
6527
6528 if (!skb_queue_empty(&chan->tx_q))
6529 chan->tx_send_head = skb_peek(&chan->tx_q);
6530 else
6531 chan->tx_send_head = NULL;
6532
6533 /* Rewind next_tx_seq to the point expected
6534 * by the receiver.
6535 */
6536 chan->next_tx_seq = control->reqseq;
6537 chan->unacked_frames = 0;
6538
6539 err = l2cap_finish_move(chan);
6540 if (err)
6541 return err;
6542
6543 set_bit(CONN_SEND_FBIT, &chan->conn_state);
6544 l2cap_send_i_or_rr_or_rnr(chan);
6545
6546 if (event == L2CAP_EV_RECV_IFRAME)
6547 return -EPROTO;
6548
6549 return l2cap_rx_state_recv(chan, control, NULL, event);
6550}
6551
6552static int l2cap_rx_state_wait_f(struct l2cap_chan *chan,
6553 struct l2cap_ctrl *control,
6554 struct sk_buff *skb, u8 event)
6555{
6556 int err;
6557
6558 if (!control->final)
6559 return -EPROTO;
6560
6561 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6562
6563 chan->rx_state = L2CAP_RX_STATE_RECV;
6564 l2cap_process_reqseq(chan, control->reqseq);
6565
6566 if (!skb_queue_empty(&chan->tx_q))
6567 chan->tx_send_head = skb_peek(&chan->tx_q);
6568 else
6569 chan->tx_send_head = NULL;
6570
6571 /* Rewind next_tx_seq to the point expected
6572 * by the receiver.
6573 */
6574 chan->next_tx_seq = control->reqseq;
6575 chan->unacked_frames = 0;
6576
6577 if (chan->hs_hcon)
6578 chan->conn->mtu = chan->hs_hcon->hdev->block_mtu;
6579 else
6580 chan->conn->mtu = chan->conn->hcon->hdev->acl_mtu;
6581
6582 err = l2cap_resegment(chan);
6583
6584 if (!err)
6585 err = l2cap_rx_state_recv(chan, control, skb, event);
6586
6587 return err;
6588}
6589
6590static bool __valid_reqseq(struct l2cap_chan *chan, u16 reqseq)
6591{
6592 /* Make sure reqseq is for a packet that has been sent but not acked */
6593 u16 unacked;
6594
6595 unacked = __seq_offset(chan, chan->next_tx_seq, chan->expected_ack_seq);
6596 return __seq_offset(chan, chan->next_tx_seq, reqseq) <= unacked;
6597}
6598
6599static int l2cap_rx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
6600 struct sk_buff *skb, u8 event)
6601{
6602 int err = 0;
6603
6604 BT_DBG("chan %p, control %p, skb %p, event %d, state %d", chan,
6605 control, skb, event, chan->rx_state);
6606
6607 if (__valid_reqseq(chan, control->reqseq)) {
6608 switch (chan->rx_state) {
6609 case L2CAP_RX_STATE_RECV:
6610 err = l2cap_rx_state_recv(chan, control, skb, event);
6611 break;
6612 case L2CAP_RX_STATE_SREJ_SENT:
6613 err = l2cap_rx_state_srej_sent(chan, control, skb,
6614 event);
6615 break;
6616 case L2CAP_RX_STATE_WAIT_P:
6617 err = l2cap_rx_state_wait_p(chan, control, skb, event);
6618 break;
6619 case L2CAP_RX_STATE_WAIT_F:
6620 err = l2cap_rx_state_wait_f(chan, control, skb, event);
6621 break;
6622 default:
6623 /* shut it down */
6624 break;
6625 }
6626 } else {
6627 BT_DBG("Invalid reqseq %d (next_tx_seq %d, expected_ack_seq %d",
6628 control->reqseq, chan->next_tx_seq,
6629 chan->expected_ack_seq);
6630 l2cap_send_disconn_req(chan, ECONNRESET);
6631 }
6632
6633 return err;
6634}
6635
6636static int l2cap_stream_rx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
6637 struct sk_buff *skb)
6638{
6639 BT_DBG("chan %p, control %p, skb %p, state %d", chan, control, skb,
6640 chan->rx_state);
6641
6642 if (l2cap_classify_txseq(chan, control->txseq) ==
6643 L2CAP_TXSEQ_EXPECTED) {
6644 l2cap_pass_to_tx(chan, control);
6645
6646 BT_DBG("buffer_seq %d->%d", chan->buffer_seq,
6647 __next_seq(chan, chan->buffer_seq));
6648
6649 chan->buffer_seq = __next_seq(chan, chan->buffer_seq);
6650
6651 l2cap_reassemble_sdu(chan, skb, control);
6652 } else {
6653 if (chan->sdu) {
6654 kfree_skb(chan->sdu);
6655 chan->sdu = NULL;
6656 }
6657 chan->sdu_last_frag = NULL;
6658 chan->sdu_len = 0;
6659
6660 if (skb) {
6661 BT_DBG("Freeing %p", skb);
6662 kfree_skb(skb);
6663 }
6664 }
6665
6666 chan->last_acked_seq = control->txseq;
6667 chan->expected_tx_seq = __next_seq(chan, control->txseq);
6668
6669 return 0;
6670}
6671
6672static int l2cap_data_rcv(struct l2cap_chan *chan, struct sk_buff *skb)
6673{
6674 struct l2cap_ctrl *control = &bt_cb(skb)->l2cap;
6675 u16 len;
6676 u8 event;
6677
6678 __unpack_control(chan, skb);
6679
6680 len = skb->len;
6681
6682 /*
6683 * We can just drop the corrupted I-frame here.
6684 * Receiver will miss it and start proper recovery
6685 * procedures and ask for retransmission.
6686 */
6687 if (l2cap_check_fcs(chan, skb))
6688 goto drop;
6689
6690 if (!control->sframe && control->sar == L2CAP_SAR_START)
6691 len -= L2CAP_SDULEN_SIZE;
6692
6693 if (chan->fcs == L2CAP_FCS_CRC16)
6694 len -= L2CAP_FCS_SIZE;
6695
6696 if (len > chan->mps) {
6697 l2cap_send_disconn_req(chan, ECONNRESET);
6698 goto drop;
6699 }
6700
6701 if ((chan->mode == L2CAP_MODE_ERTM ||
6702 chan->mode == L2CAP_MODE_STREAMING) && sk_filter(chan->data, skb))
6703 goto drop;
6704
6705 if (!control->sframe) {
6706 int err;
6707
6708 BT_DBG("iframe sar %d, reqseq %d, final %d, txseq %d",
6709 control->sar, control->reqseq, control->final,
6710 control->txseq);
6711
6712 /* Validate F-bit - F=0 always valid, F=1 only
6713 * valid in TX WAIT_F
6714 */
6715 if (control->final && chan->tx_state != L2CAP_TX_STATE_WAIT_F)
6716 goto drop;
6717
6718 if (chan->mode != L2CAP_MODE_STREAMING) {
6719 event = L2CAP_EV_RECV_IFRAME;
6720 err = l2cap_rx(chan, control, skb, event);
6721 } else {
6722 err = l2cap_stream_rx(chan, control, skb);
6723 }
6724
6725 if (err)
6726 l2cap_send_disconn_req(chan, ECONNRESET);
6727 } else {
6728 const u8 rx_func_to_event[4] = {
6729 L2CAP_EV_RECV_RR, L2CAP_EV_RECV_REJ,
6730 L2CAP_EV_RECV_RNR, L2CAP_EV_RECV_SREJ
6731 };
6732
6733 /* Only I-frames are expected in streaming mode */
6734 if (chan->mode == L2CAP_MODE_STREAMING)
6735 goto drop;
6736
6737 BT_DBG("sframe reqseq %d, final %d, poll %d, super %d",
6738 control->reqseq, control->final, control->poll,
6739 control->super);
6740
6741 if (len != 0) {
6742 BT_ERR("Trailing bytes: %d in sframe", len);
6743 l2cap_send_disconn_req(chan, ECONNRESET);
6744 goto drop;
6745 }
6746
6747 /* Validate F and P bits */
6748 if (control->final && (control->poll ||
6749 chan->tx_state != L2CAP_TX_STATE_WAIT_F))
6750 goto drop;
6751
6752 event = rx_func_to_event[control->super];
6753 if (l2cap_rx(chan, control, skb, event))
6754 l2cap_send_disconn_req(chan, ECONNRESET);
6755 }
6756
6757 return 0;
6758
6759drop:
6760 kfree_skb(skb);
6761 return 0;
6762}
6763
6764static void l2cap_chan_le_send_credits(struct l2cap_chan *chan)
6765{
6766 struct l2cap_conn *conn = chan->conn;
6767 struct l2cap_le_credits pkt;
6768 u16 return_credits;
6769
6770 return_credits = ((chan->imtu / chan->mps) + 1) - chan->rx_credits;
6771
6772 if (!return_credits)
6773 return;
6774
6775 BT_DBG("chan %p returning %u credits to sender", chan, return_credits);
6776
6777 chan->rx_credits += return_credits;
6778
6779 pkt.cid = cpu_to_le16(chan->scid);
6780 pkt.credits = cpu_to_le16(return_credits);
6781
6782 chan->ident = l2cap_get_ident(conn);
6783
6784 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CREDITS, sizeof(pkt), &pkt);
6785}
6786
6787static int l2cap_le_recv(struct l2cap_chan *chan, struct sk_buff *skb)
6788{
6789 int err;
6790
6791 BT_DBG("SDU reassemble complete: chan %p skb->len %u", chan, skb->len);
6792
6793 /* Wait recv to confirm reception before updating the credits */
6794 err = chan->ops->recv(chan, skb);
6795
6796 /* Update credits whenever an SDU is received */
6797 l2cap_chan_le_send_credits(chan);
6798
6799 return err;
6800}
6801
6802static int l2cap_le_data_rcv(struct l2cap_chan *chan, struct sk_buff *skb)
6803{
6804 int err;
6805
6806 if (!chan->rx_credits) {
6807 BT_ERR("No credits to receive LE L2CAP data");
6808 l2cap_send_disconn_req(chan, ECONNRESET);
6809 return -ENOBUFS;
6810 }
6811
6812 if (chan->imtu < skb->len) {
6813 BT_ERR("Too big LE L2CAP PDU");
6814 return -ENOBUFS;
6815 }
6816
6817 chan->rx_credits--;
6818 BT_DBG("rx_credits %u -> %u", chan->rx_credits + 1, chan->rx_credits);
6819
6820 /* Update if remote had run out of credits, this should only happens
6821 * if the remote is not using the entire MPS.
6822 */
6823 if (!chan->rx_credits)
6824 l2cap_chan_le_send_credits(chan);
6825
6826 err = 0;
6827
6828 if (!chan->sdu) {
6829 u16 sdu_len;
6830
6831 sdu_len = get_unaligned_le16(skb->data);
6832 skb_pull(skb, L2CAP_SDULEN_SIZE);
6833
6834 BT_DBG("Start of new SDU. sdu_len %u skb->len %u imtu %u",
6835 sdu_len, skb->len, chan->imtu);
6836
6837 if (sdu_len > chan->imtu) {
6838 BT_ERR("Too big LE L2CAP SDU length received");
6839 err = -EMSGSIZE;
6840 goto failed;
6841 }
6842
6843 if (skb->len > sdu_len) {
6844 BT_ERR("Too much LE L2CAP data received");
6845 err = -EINVAL;
6846 goto failed;
6847 }
6848
6849 if (skb->len == sdu_len)
6850 return l2cap_le_recv(chan, skb);
6851
6852 chan->sdu = skb;
6853 chan->sdu_len = sdu_len;
6854 chan->sdu_last_frag = skb;
6855
6856 /* Detect if remote is not able to use the selected MPS */
6857 if (skb->len + L2CAP_SDULEN_SIZE < chan->mps) {
6858 u16 mps_len = skb->len + L2CAP_SDULEN_SIZE;
6859
6860 /* Adjust the number of credits */
6861 BT_DBG("chan->mps %u -> %u", chan->mps, mps_len);
6862 chan->mps = mps_len;
6863 l2cap_chan_le_send_credits(chan);
6864 }
6865
6866 return 0;
6867 }
6868
6869 BT_DBG("SDU fragment. chan->sdu->len %u skb->len %u chan->sdu_len %u",
6870 chan->sdu->len, skb->len, chan->sdu_len);
6871
6872 if (chan->sdu->len + skb->len > chan->sdu_len) {
6873 BT_ERR("Too much LE L2CAP data received");
6874 err = -EINVAL;
6875 goto failed;
6876 }
6877
6878 append_skb_frag(chan->sdu, skb, &chan->sdu_last_frag);
6879 skb = NULL;
6880
6881 if (chan->sdu->len == chan->sdu_len) {
6882 err = l2cap_le_recv(chan, chan->sdu);
6883 if (!err) {
6884 chan->sdu = NULL;
6885 chan->sdu_last_frag = NULL;
6886 chan->sdu_len = 0;
6887 }
6888 }
6889
6890failed:
6891 if (err) {
6892 kfree_skb(skb);
6893 kfree_skb(chan->sdu);
6894 chan->sdu = NULL;
6895 chan->sdu_last_frag = NULL;
6896 chan->sdu_len = 0;
6897 }
6898
6899 /* We can't return an error here since we took care of the skb
6900 * freeing internally. An error return would cause the caller to
6901 * do a double-free of the skb.
6902 */
6903 return 0;
6904}
6905
6906static void l2cap_data_channel(struct l2cap_conn *conn, u16 cid,
6907 struct sk_buff *skb)
6908{
6909 struct l2cap_chan *chan;
6910
6911 chan = l2cap_get_chan_by_scid(conn, cid);
6912 if (!chan) {
6913 if (cid == L2CAP_CID_A2MP) {
6914 chan = a2mp_channel_create(conn, skb);
6915 if (!chan) {
6916 kfree_skb(skb);
6917 return;
6918 }
6919
6920 l2cap_chan_lock(chan);
6921 } else {
6922 BT_DBG("unknown cid 0x%4.4x", cid);
6923 /* Drop packet and return */
6924 kfree_skb(skb);
6925 return;
6926 }
6927 }
6928
6929 BT_DBG("chan %p, len %d", chan, skb->len);
6930
6931 /* If we receive data on a fixed channel before the info req/rsp
6932 * procdure is done simply assume that the channel is supported
6933 * and mark it as ready.
6934 */
6935 if (chan->chan_type == L2CAP_CHAN_FIXED)
6936 l2cap_chan_ready(chan);
6937
6938 if (chan->state != BT_CONNECTED)
6939 goto drop;
6940
6941 switch (chan->mode) {
6942 case L2CAP_MODE_LE_FLOWCTL:
6943 if (l2cap_le_data_rcv(chan, skb) < 0)
6944 goto drop;
6945
6946 goto done;
6947
6948 case L2CAP_MODE_BASIC:
6949 /* If socket recv buffers overflows we drop data here
6950 * which is *bad* because L2CAP has to be reliable.
6951 * But we don't have any other choice. L2CAP doesn't
6952 * provide flow control mechanism. */
6953
6954 if (chan->imtu < skb->len) {
6955 BT_ERR("Dropping L2CAP data: receive buffer overflow");
6956 goto drop;
6957 }
6958
6959 if (!chan->ops->recv(chan, skb))
6960 goto done;
6961 break;
6962
6963 case L2CAP_MODE_ERTM:
6964 case L2CAP_MODE_STREAMING:
6965 l2cap_data_rcv(chan, skb);
6966 goto done;
6967
6968 default:
6969 BT_DBG("chan %p: bad mode 0x%2.2x", chan, chan->mode);
6970 break;
6971 }
6972
6973drop:
6974 kfree_skb(skb);
6975
6976done:
6977 l2cap_chan_unlock(chan);
6978}
6979
6980static void l2cap_conless_channel(struct l2cap_conn *conn, __le16 psm,
6981 struct sk_buff *skb)
6982{
6983 struct hci_conn *hcon = conn->hcon;
6984 struct l2cap_chan *chan;
6985
6986 if (hcon->type != ACL_LINK)
6987 goto free_skb;
6988
6989 chan = l2cap_global_chan_by_psm(0, psm, &hcon->src, &hcon->dst,
6990 ACL_LINK);
6991 if (!chan)
6992 goto free_skb;
6993
6994 BT_DBG("chan %p, len %d", chan, skb->len);
6995
6996 if (chan->state != BT_BOUND && chan->state != BT_CONNECTED)
6997 goto drop;
6998
6999 if (chan->imtu < skb->len)
7000 goto drop;
7001
7002 /* Store remote BD_ADDR and PSM for msg_name */
7003 bacpy(&bt_cb(skb)->l2cap.bdaddr, &hcon->dst);
7004 bt_cb(skb)->l2cap.psm = psm;
7005
7006 if (!chan->ops->recv(chan, skb)) {
7007 l2cap_chan_put(chan);
7008 return;
7009 }
7010
7011drop:
7012 l2cap_chan_put(chan);
7013free_skb:
7014 kfree_skb(skb);
7015}
7016
7017static void l2cap_recv_frame(struct l2cap_conn *conn, struct sk_buff *skb)
7018{
7019 struct l2cap_hdr *lh = (void *) skb->data;
7020 struct hci_conn *hcon = conn->hcon;
7021 u16 cid, len;
7022 __le16 psm;
7023
7024 if (hcon->state != BT_CONNECTED) {
7025 BT_DBG("queueing pending rx skb");
7026 skb_queue_tail(&conn->pending_rx, skb);
7027 return;
7028 }
7029
7030 skb_pull(skb, L2CAP_HDR_SIZE);
7031 cid = __le16_to_cpu(lh->cid);
7032 len = __le16_to_cpu(lh->len);
7033
7034 if (len != skb->len) {
7035 kfree_skb(skb);
7036 return;
7037 }
7038
7039 /* Since we can't actively block incoming LE connections we must
7040 * at least ensure that we ignore incoming data from them.
7041 */
7042 if (hcon->type == LE_LINK &&
7043 hci_bdaddr_list_lookup(&hcon->hdev->blacklist, &hcon->dst,
7044 bdaddr_dst_type(hcon))) {
7045 kfree_skb(skb);
7046 return;
7047 }
7048
7049 BT_DBG("len %d, cid 0x%4.4x", len, cid);
7050
7051 switch (cid) {
7052 case L2CAP_CID_SIGNALING:
7053 l2cap_sig_channel(conn, skb);
7054 break;
7055
7056 case L2CAP_CID_CONN_LESS:
7057 psm = get_unaligned((__le16 *) skb->data);
7058 skb_pull(skb, L2CAP_PSMLEN_SIZE);
7059 l2cap_conless_channel(conn, psm, skb);
7060 break;
7061
7062 case L2CAP_CID_LE_SIGNALING:
7063 l2cap_le_sig_channel(conn, skb);
7064 break;
7065
7066 default:
7067 l2cap_data_channel(conn, cid, skb);
7068 break;
7069 }
7070}
7071
7072static void process_pending_rx(struct work_struct *work)
7073{
7074 struct l2cap_conn *conn = container_of(work, struct l2cap_conn,
7075 pending_rx_work);
7076 struct sk_buff *skb;
7077
7078 BT_DBG("");
7079
7080 while ((skb = skb_dequeue(&conn->pending_rx)))
7081 l2cap_recv_frame(conn, skb);
7082}
7083
7084static struct l2cap_conn *l2cap_conn_add(struct hci_conn *hcon)
7085{
7086 struct l2cap_conn *conn = hcon->l2cap_data;
7087 struct hci_chan *hchan;
7088
7089 if (conn)
7090 return conn;
7091
7092 hchan = hci_chan_create(hcon);
7093 if (!hchan)
7094 return NULL;
7095
7096 conn = kzalloc(sizeof(*conn), GFP_KERNEL);
7097 if (!conn) {
7098 hci_chan_del(hchan);
7099 return NULL;
7100 }
7101
7102 kref_init(&conn->ref);
7103 hcon->l2cap_data = conn;
7104 conn->hcon = hci_conn_get(hcon);
7105 conn->hchan = hchan;
7106
7107 BT_DBG("hcon %p conn %p hchan %p", hcon, conn, hchan);
7108
7109 switch (hcon->type) {
7110 case LE_LINK:
7111 if (hcon->hdev->le_mtu) {
7112 conn->mtu = hcon->hdev->le_mtu;
7113 break;
7114 }
7115 /* fall through */
7116 default:
7117 conn->mtu = hcon->hdev->acl_mtu;
7118 break;
7119 }
7120
7121 conn->feat_mask = 0;
7122
7123 conn->local_fixed_chan = L2CAP_FC_SIG_BREDR | L2CAP_FC_CONNLESS;
7124
7125 if (hcon->type == ACL_LINK &&
7126 hci_dev_test_flag(hcon->hdev, HCI_HS_ENABLED))
7127 conn->local_fixed_chan |= L2CAP_FC_A2MP;
7128
7129 if (hci_dev_test_flag(hcon->hdev, HCI_LE_ENABLED) &&
7130 (bredr_sc_enabled(hcon->hdev) ||
7131 hci_dev_test_flag(hcon->hdev, HCI_FORCE_BREDR_SMP)))
7132 conn->local_fixed_chan |= L2CAP_FC_SMP_BREDR;
7133
7134 mutex_init(&conn->ident_lock);
7135 mutex_init(&conn->chan_lock);
7136
7137 INIT_LIST_HEAD(&conn->chan_l);
7138 INIT_LIST_HEAD(&conn->users);
7139
7140 INIT_DELAYED_WORK(&conn->info_timer, l2cap_info_timeout);
7141
7142 skb_queue_head_init(&conn->pending_rx);
7143 INIT_WORK(&conn->pending_rx_work, process_pending_rx);
7144 INIT_WORK(&conn->id_addr_update_work, l2cap_conn_update_id_addr);
7145
7146 conn->disc_reason = HCI_ERROR_REMOTE_USER_TERM;
7147
7148 return conn;
7149}
7150
7151static bool is_valid_psm(u16 psm, u8 dst_type) {
7152 if (!psm)
7153 return false;
7154
7155 if (bdaddr_type_is_le(dst_type))
7156 return (psm <= 0x00ff);
7157
7158 /* PSM must be odd and lsb of upper byte must be 0 */
7159 return ((psm & 0x0101) == 0x0001);
7160}
7161
7162int l2cap_chan_connect(struct l2cap_chan *chan, __le16 psm, u16 cid,
7163 bdaddr_t *dst, u8 dst_type)
7164{
7165 struct l2cap_conn *conn;
7166 struct hci_conn *hcon;
7167 struct hci_dev *hdev;
7168 int err;
7169
7170 BT_DBG("%pMR -> %pMR (type %u) psm 0x%2.2x", &chan->src, dst,
7171 dst_type, __le16_to_cpu(psm));
7172
7173 hdev = hci_get_route(dst, &chan->src, chan->src_type);
7174 if (!hdev)
7175 return -EHOSTUNREACH;
7176
7177 hci_dev_lock(hdev);
7178
7179 if (!is_valid_psm(__le16_to_cpu(psm), dst_type) && !cid &&
7180 chan->chan_type != L2CAP_CHAN_RAW) {
7181 err = -EINVAL;
7182 goto done;
7183 }
7184
7185 if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED && !psm) {
7186 err = -EINVAL;
7187 goto done;
7188 }
7189
7190 if (chan->chan_type == L2CAP_CHAN_FIXED && !cid) {
7191 err = -EINVAL;
7192 goto done;
7193 }
7194
7195 switch (chan->mode) {
7196 case L2CAP_MODE_BASIC:
7197 break;
7198 case L2CAP_MODE_LE_FLOWCTL:
7199 break;
7200 case L2CAP_MODE_ERTM:
7201 case L2CAP_MODE_STREAMING:
7202 if (!disable_ertm)
7203 break;
7204 /* fall through */
7205 default:
7206 err = -EOPNOTSUPP;
7207 goto done;
7208 }
7209
7210 switch (chan->state) {
7211 case BT_CONNECT:
7212 case BT_CONNECT2:
7213 case BT_CONFIG:
7214 /* Already connecting */
7215 err = 0;
7216 goto done;
7217
7218 case BT_CONNECTED:
7219 /* Already connected */
7220 err = -EISCONN;
7221 goto done;
7222
7223 case BT_OPEN:
7224 case BT_BOUND:
7225 /* Can connect */
7226 break;
7227
7228 default:
7229 err = -EBADFD;
7230 goto done;
7231 }
7232
7233 /* Set destination address and psm */
7234 bacpy(&chan->dst, dst);
7235 chan->dst_type = dst_type;
7236
7237 chan->psm = psm;
7238 chan->dcid = cid;
7239
7240 if (bdaddr_type_is_le(dst_type)) {
7241 /* Convert from L2CAP channel address type to HCI address type
7242 */
7243 if (dst_type == BDADDR_LE_PUBLIC)
7244 dst_type = ADDR_LE_DEV_PUBLIC;
7245 else
7246 dst_type = ADDR_LE_DEV_RANDOM;
7247
7248 if (hci_dev_test_flag(hdev, HCI_ADVERTISING))
7249 hcon = hci_connect_le(hdev, dst, dst_type,
7250 chan->sec_level,
7251 HCI_LE_CONN_TIMEOUT,
7252 HCI_ROLE_SLAVE, NULL);
7253 else
7254 hcon = hci_connect_le_scan(hdev, dst, dst_type,
7255 chan->sec_level,
7256 HCI_LE_CONN_TIMEOUT);
7257
7258 } else {
7259 u8 auth_type = l2cap_get_auth_type(chan);
7260 hcon = hci_connect_acl(hdev, dst, chan->sec_level, auth_type);
7261 }
7262
7263 if (IS_ERR(hcon)) {
7264 err = PTR_ERR(hcon);
7265 goto done;
7266 }
7267
7268 conn = l2cap_conn_add(hcon);
7269 if (!conn) {
7270 hci_conn_drop(hcon);
7271 err = -ENOMEM;
7272 goto done;
7273 }
7274
7275 mutex_lock(&conn->chan_lock);
7276 l2cap_chan_lock(chan);
7277
7278 if (cid && __l2cap_get_chan_by_dcid(conn, cid)) {
7279 hci_conn_drop(hcon);
7280 err = -EBUSY;
7281 goto chan_unlock;
7282 }
7283
7284 /* Update source addr of the socket */
7285 bacpy(&chan->src, &hcon->src);
7286 chan->src_type = bdaddr_src_type(hcon);
7287
7288 __l2cap_chan_add(conn, chan);
7289
7290 /* l2cap_chan_add takes its own ref so we can drop this one */
7291 hci_conn_drop(hcon);
7292
7293 l2cap_state_change(chan, BT_CONNECT);
7294 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
7295
7296 /* Release chan->sport so that it can be reused by other
7297 * sockets (as it's only used for listening sockets).
7298 */
7299 write_lock(&chan_list_lock);
7300 chan->sport = 0;
7301 write_unlock(&chan_list_lock);
7302
7303 if (hcon->state == BT_CONNECTED) {
7304 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
7305 __clear_chan_timer(chan);
7306 if (l2cap_chan_check_security(chan, true))
7307 l2cap_state_change(chan, BT_CONNECTED);
7308 } else
7309 l2cap_do_start(chan);
7310 }
7311
7312 err = 0;
7313
7314chan_unlock:
7315 l2cap_chan_unlock(chan);
7316 mutex_unlock(&conn->chan_lock);
7317done:
7318 hci_dev_unlock(hdev);
7319 hci_dev_put(hdev);
7320 return err;
7321}
7322EXPORT_SYMBOL_GPL(l2cap_chan_connect);
7323
7324/* ---- L2CAP interface with lower layer (HCI) ---- */
7325
7326int l2cap_connect_ind(struct hci_dev *hdev, bdaddr_t *bdaddr)
7327{
7328 int exact = 0, lm1 = 0, lm2 = 0;
7329 struct l2cap_chan *c;
7330
7331 BT_DBG("hdev %s, bdaddr %pMR", hdev->name, bdaddr);
7332
7333 /* Find listening sockets and check their link_mode */
7334 read_lock(&chan_list_lock);
7335 list_for_each_entry(c, &chan_list, global_l) {
7336 if (c->state != BT_LISTEN)
7337 continue;
7338
7339 if (!bacmp(&c->src, &hdev->bdaddr)) {
7340 lm1 |= HCI_LM_ACCEPT;
7341 if (test_bit(FLAG_ROLE_SWITCH, &c->flags))
7342 lm1 |= HCI_LM_MASTER;
7343 exact++;
7344 } else if (!bacmp(&c->src, BDADDR_ANY)) {
7345 lm2 |= HCI_LM_ACCEPT;
7346 if (test_bit(FLAG_ROLE_SWITCH, &c->flags))
7347 lm2 |= HCI_LM_MASTER;
7348 }
7349 }
7350 read_unlock(&chan_list_lock);
7351
7352 return exact ? lm1 : lm2;
7353}
7354
7355/* Find the next fixed channel in BT_LISTEN state, continue iteration
7356 * from an existing channel in the list or from the beginning of the
7357 * global list (by passing NULL as first parameter).
7358 */
7359static struct l2cap_chan *l2cap_global_fixed_chan(struct l2cap_chan *c,
7360 struct hci_conn *hcon)
7361{
7362 u8 src_type = bdaddr_src_type(hcon);
7363
7364 read_lock(&chan_list_lock);
7365
7366 if (c)
7367 c = list_next_entry(c, global_l);
7368 else
7369 c = list_entry(chan_list.next, typeof(*c), global_l);
7370
7371 list_for_each_entry_from(c, &chan_list, global_l) {
7372 if (c->chan_type != L2CAP_CHAN_FIXED)
7373 continue;
7374 if (c->state != BT_LISTEN)
7375 continue;
7376 if (bacmp(&c->src, &hcon->src) && bacmp(&c->src, BDADDR_ANY))
7377 continue;
7378 if (src_type != c->src_type)
7379 continue;
7380
7381 l2cap_chan_hold(c);
7382 read_unlock(&chan_list_lock);
7383 return c;
7384 }
7385
7386 read_unlock(&chan_list_lock);
7387
7388 return NULL;
7389}
7390
7391static void l2cap_connect_cfm(struct hci_conn *hcon, u8 status)
7392{
7393 struct hci_dev *hdev = hcon->hdev;
7394 struct l2cap_conn *conn;
7395 struct l2cap_chan *pchan;
7396 u8 dst_type;
7397
7398 if (hcon->type != ACL_LINK && hcon->type != LE_LINK)
7399 return;
7400
7401 BT_DBG("hcon %p bdaddr %pMR status %d", hcon, &hcon->dst, status);
7402
7403 if (status) {
7404 l2cap_conn_del(hcon, bt_to_errno(status));
7405 return;
7406 }
7407
7408 conn = l2cap_conn_add(hcon);
7409 if (!conn)
7410 return;
7411
7412 dst_type = bdaddr_dst_type(hcon);
7413
7414 /* If device is blocked, do not create channels for it */
7415 if (hci_bdaddr_list_lookup(&hdev->blacklist, &hcon->dst, dst_type))
7416 return;
7417
7418 /* Find fixed channels and notify them of the new connection. We
7419 * use multiple individual lookups, continuing each time where
7420 * we left off, because the list lock would prevent calling the
7421 * potentially sleeping l2cap_chan_lock() function.
7422 */
7423 pchan = l2cap_global_fixed_chan(NULL, hcon);
7424 while (pchan) {
7425 struct l2cap_chan *chan, *next;
7426
7427 /* Client fixed channels should override server ones */
7428 if (__l2cap_get_chan_by_dcid(conn, pchan->scid))
7429 goto next;
7430
7431 l2cap_chan_lock(pchan);
7432 chan = pchan->ops->new_connection(pchan);
7433 if (chan) {
7434 bacpy(&chan->src, &hcon->src);
7435 bacpy(&chan->dst, &hcon->dst);
7436 chan->src_type = bdaddr_src_type(hcon);
7437 chan->dst_type = dst_type;
7438
7439 __l2cap_chan_add(conn, chan);
7440 }
7441
7442 l2cap_chan_unlock(pchan);
7443next:
7444 next = l2cap_global_fixed_chan(pchan, hcon);
7445 l2cap_chan_put(pchan);
7446 pchan = next;
7447 }
7448
7449 l2cap_conn_ready(conn);
7450}
7451
7452int l2cap_disconn_ind(struct hci_conn *hcon)
7453{
7454 struct l2cap_conn *conn = hcon->l2cap_data;
7455
7456 BT_DBG("hcon %p", hcon);
7457
7458 if (!conn)
7459 return HCI_ERROR_REMOTE_USER_TERM;
7460 return conn->disc_reason;
7461}
7462
7463static void l2cap_disconn_cfm(struct hci_conn *hcon, u8 reason)
7464{
7465 if (hcon->type != ACL_LINK && hcon->type != LE_LINK)
7466 return;
7467
7468 BT_DBG("hcon %p reason %d", hcon, reason);
7469
7470 l2cap_conn_del(hcon, bt_to_errno(reason));
7471}
7472
7473static inline void l2cap_check_encryption(struct l2cap_chan *chan, u8 encrypt)
7474{
7475 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED)
7476 return;
7477
7478 if (encrypt == 0x00) {
7479 if (chan->sec_level == BT_SECURITY_MEDIUM) {
7480 __set_chan_timer(chan, L2CAP_ENC_TIMEOUT);
7481 } else if (chan->sec_level == BT_SECURITY_HIGH ||
7482 chan->sec_level == BT_SECURITY_FIPS)
7483 l2cap_chan_close(chan, ECONNREFUSED);
7484 } else {
7485 if (chan->sec_level == BT_SECURITY_MEDIUM)
7486 __clear_chan_timer(chan);
7487 }
7488}
7489
7490static void l2cap_security_cfm(struct hci_conn *hcon, u8 status, u8 encrypt)
7491{
7492 struct l2cap_conn *conn = hcon->l2cap_data;
7493 struct l2cap_chan *chan;
7494
7495 if (!conn)
7496 return;
7497
7498 BT_DBG("conn %p status 0x%2.2x encrypt %u", conn, status, encrypt);
7499
7500 mutex_lock(&conn->chan_lock);
7501
7502 list_for_each_entry(chan, &conn->chan_l, list) {
7503 l2cap_chan_lock(chan);
7504
7505 BT_DBG("chan %p scid 0x%4.4x state %s", chan, chan->scid,
7506 state_to_string(chan->state));
7507
7508 if (chan->scid == L2CAP_CID_A2MP) {
7509 l2cap_chan_unlock(chan);
7510 continue;
7511 }
7512
7513 if (!status && encrypt)
7514 chan->sec_level = hcon->sec_level;
7515
7516 if (!__l2cap_no_conn_pending(chan)) {
7517 l2cap_chan_unlock(chan);
7518 continue;
7519 }
7520
7521 if (!status && (chan->state == BT_CONNECTED ||
7522 chan->state == BT_CONFIG)) {
7523 chan->ops->resume(chan);
7524 l2cap_check_encryption(chan, encrypt);
7525 l2cap_chan_unlock(chan);
7526 continue;
7527 }
7528
7529 if (chan->state == BT_CONNECT) {
7530 if (!status && l2cap_check_enc_key_size(hcon))
7531 l2cap_start_connection(chan);
7532 else
7533 __set_chan_timer(chan, L2CAP_DISC_TIMEOUT);
7534 } else if (chan->state == BT_CONNECT2 &&
7535 chan->mode != L2CAP_MODE_LE_FLOWCTL) {
7536 struct l2cap_conn_rsp rsp;
7537 __u16 res, stat;
7538
7539 if (!status && l2cap_check_enc_key_size(hcon)) {
7540 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
7541 res = L2CAP_CR_PEND;
7542 stat = L2CAP_CS_AUTHOR_PEND;
7543 chan->ops->defer(chan);
7544 } else {
7545 l2cap_state_change(chan, BT_CONFIG);
7546 res = L2CAP_CR_SUCCESS;
7547 stat = L2CAP_CS_NO_INFO;
7548 }
7549 } else {
7550 l2cap_state_change(chan, BT_DISCONN);
7551 __set_chan_timer(chan, L2CAP_DISC_TIMEOUT);
7552 res = L2CAP_CR_SEC_BLOCK;
7553 stat = L2CAP_CS_NO_INFO;
7554 }
7555
7556 rsp.scid = cpu_to_le16(chan->dcid);
7557 rsp.dcid = cpu_to_le16(chan->scid);
7558 rsp.result = cpu_to_le16(res);
7559 rsp.status = cpu_to_le16(stat);
7560 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP,
7561 sizeof(rsp), &rsp);
7562
7563 if (!test_bit(CONF_REQ_SENT, &chan->conf_state) &&
7564 res == L2CAP_CR_SUCCESS) {
7565 char buf[128];
7566 set_bit(CONF_REQ_SENT, &chan->conf_state);
7567 l2cap_send_cmd(conn, l2cap_get_ident(conn),
7568 L2CAP_CONF_REQ,
7569 l2cap_build_conf_req(chan, buf, sizeof(buf)),
7570 buf);
7571 chan->num_conf_req++;
7572 }
7573 }
7574
7575 l2cap_chan_unlock(chan);
7576 }
7577
7578 mutex_unlock(&conn->chan_lock);
7579}
7580
7581void l2cap_recv_acldata(struct hci_conn *hcon, struct sk_buff *skb, u16 flags)
7582{
7583 struct l2cap_conn *conn = hcon->l2cap_data;
7584 struct l2cap_hdr *hdr;
7585 int len;
7586
7587 /* For AMP controller do not create l2cap conn */
7588 if (!conn && hcon->hdev->dev_type != HCI_PRIMARY)
7589 goto drop;
7590
7591 if (!conn)
7592 conn = l2cap_conn_add(hcon);
7593
7594 if (!conn)
7595 goto drop;
7596
7597 BT_DBG("conn %p len %d flags 0x%x", conn, skb->len, flags);
7598
7599 switch (flags) {
7600 case ACL_START:
7601 case ACL_START_NO_FLUSH:
7602 case ACL_COMPLETE:
7603 if (conn->rx_len) {
7604 BT_ERR("Unexpected start frame (len %d)", skb->len);
7605 kfree_skb(conn->rx_skb);
7606 conn->rx_skb = NULL;
7607 conn->rx_len = 0;
7608 l2cap_conn_unreliable(conn, ECOMM);
7609 }
7610
7611 /* Start fragment always begin with Basic L2CAP header */
7612 if (skb->len < L2CAP_HDR_SIZE) {
7613 BT_ERR("Frame is too short (len %d)", skb->len);
7614 l2cap_conn_unreliable(conn, ECOMM);
7615 goto drop;
7616 }
7617
7618 hdr = (struct l2cap_hdr *) skb->data;
7619 len = __le16_to_cpu(hdr->len) + L2CAP_HDR_SIZE;
7620
7621 if (len == skb->len) {
7622 /* Complete frame received */
7623 l2cap_recv_frame(conn, skb);
7624 return;
7625 }
7626
7627 BT_DBG("Start: total len %d, frag len %d", len, skb->len);
7628
7629 if (skb->len > len) {
7630 BT_ERR("Frame is too long (len %d, expected len %d)",
7631 skb->len, len);
7632 l2cap_conn_unreliable(conn, ECOMM);
7633 goto drop;
7634 }
7635
7636 /* Allocate skb for the complete frame (with header) */
7637 conn->rx_skb = bt_skb_alloc(len, GFP_KERNEL);
7638 if (!conn->rx_skb)
7639 goto drop;
7640
7641 skb_copy_from_linear_data(skb, skb_put(conn->rx_skb, skb->len),
7642 skb->len);
7643 conn->rx_len = len - skb->len;
7644 break;
7645
7646 case ACL_CONT:
7647 BT_DBG("Cont: frag len %d (expecting %d)", skb->len, conn->rx_len);
7648
7649 if (!conn->rx_len) {
7650 BT_ERR("Unexpected continuation frame (len %d)", skb->len);
7651 l2cap_conn_unreliable(conn, ECOMM);
7652 goto drop;
7653 }
7654
7655 if (skb->len > conn->rx_len) {
7656 BT_ERR("Fragment is too long (len %d, expected %d)",
7657 skb->len, conn->rx_len);
7658 kfree_skb(conn->rx_skb);
7659 conn->rx_skb = NULL;
7660 conn->rx_len = 0;
7661 l2cap_conn_unreliable(conn, ECOMM);
7662 goto drop;
7663 }
7664
7665 skb_copy_from_linear_data(skb, skb_put(conn->rx_skb, skb->len),
7666 skb->len);
7667 conn->rx_len -= skb->len;
7668
7669 if (!conn->rx_len) {
7670 /* Complete frame received. l2cap_recv_frame
7671 * takes ownership of the skb so set the global
7672 * rx_skb pointer to NULL first.
7673 */
7674 struct sk_buff *rx_skb = conn->rx_skb;
7675 conn->rx_skb = NULL;
7676 l2cap_recv_frame(conn, rx_skb);
7677 }
7678 break;
7679 }
7680
7681drop:
7682 kfree_skb(skb);
7683}
7684
7685static struct hci_cb l2cap_cb = {
7686 .name = "L2CAP",
7687 .connect_cfm = l2cap_connect_cfm,
7688 .disconn_cfm = l2cap_disconn_cfm,
7689 .security_cfm = l2cap_security_cfm,
7690};
7691
7692static int l2cap_debugfs_show(struct seq_file *f, void *p)
7693{
7694 struct l2cap_chan *c;
7695
7696 read_lock(&chan_list_lock);
7697
7698 list_for_each_entry(c, &chan_list, global_l) {
7699 seq_printf(f, "%pMR (%u) %pMR (%u) %d %d 0x%4.4x 0x%4.4x %d %d %d %d\n",
7700 &c->src, c->src_type, &c->dst, c->dst_type,
7701 c->state, __le16_to_cpu(c->psm),
7702 c->scid, c->dcid, c->imtu, c->omtu,
7703 c->sec_level, c->mode);
7704 }
7705
7706 read_unlock(&chan_list_lock);
7707
7708 return 0;
7709}
7710
7711DEFINE_SHOW_ATTRIBUTE(l2cap_debugfs);
7712
7713static struct dentry *l2cap_debugfs;
7714
7715int __init l2cap_init(void)
7716{
7717 int err;
7718
7719 err = l2cap_init_sockets();
7720 if (err < 0)
7721 return err;
7722
7723 hci_register_cb(&l2cap_cb);
7724
7725 if (IS_ERR_OR_NULL(bt_debugfs))
7726 return 0;
7727
7728 l2cap_debugfs = debugfs_create_file("l2cap", 0444, bt_debugfs,
7729 NULL, &l2cap_debugfs_fops);
7730
7731 return 0;
7732}
7733
7734void l2cap_exit(void)
7735{
7736 debugfs_remove(l2cap_debugfs);
7737 hci_unregister_cb(&l2cap_cb);
7738 l2cap_cleanup_sockets();
7739}
7740
7741module_param(disable_ertm, bool, 0644);
7742MODULE_PARM_DESC(disable_ertm, "Disable enhanced retransmission mode");
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#include "6lowpan.h"
44
45#define LE_FLOWCTL_MAX_CREDITS 65535
46
47bool disable_ertm;
48
49static u32 l2cap_feat_mask = L2CAP_FEAT_FIXED_CHAN | L2CAP_FEAT_UCD;
50static u8 l2cap_fixed_chan[8] = { L2CAP_FC_L2CAP | L2CAP_FC_CONNLESS, };
51
52static LIST_HEAD(chan_list);
53static DEFINE_RWLOCK(chan_list_lock);
54
55static u16 le_max_credits = L2CAP_LE_MAX_CREDITS;
56static u16 le_default_mps = L2CAP_LE_DEFAULT_MPS;
57
58static struct sk_buff *l2cap_build_cmd(struct l2cap_conn *conn,
59 u8 code, u8 ident, u16 dlen, void *data);
60static void l2cap_send_cmd(struct l2cap_conn *conn, u8 ident, u8 code, u16 len,
61 void *data);
62static int l2cap_build_conf_req(struct l2cap_chan *chan, void *data);
63static void l2cap_send_disconn_req(struct l2cap_chan *chan, int err);
64
65static void l2cap_tx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
66 struct sk_buff_head *skbs, u8 event);
67
68static inline __u8 bdaddr_type(struct hci_conn *hcon, __u8 type)
69{
70 if (hcon->type == LE_LINK) {
71 if (type == ADDR_LE_DEV_PUBLIC)
72 return BDADDR_LE_PUBLIC;
73 else
74 return BDADDR_LE_RANDOM;
75 }
76
77 return BDADDR_BREDR;
78}
79
80/* ---- L2CAP channels ---- */
81
82static struct l2cap_chan *__l2cap_get_chan_by_dcid(struct l2cap_conn *conn,
83 u16 cid)
84{
85 struct l2cap_chan *c;
86
87 list_for_each_entry(c, &conn->chan_l, list) {
88 if (c->dcid == cid)
89 return c;
90 }
91 return NULL;
92}
93
94static struct l2cap_chan *__l2cap_get_chan_by_scid(struct l2cap_conn *conn,
95 u16 cid)
96{
97 struct l2cap_chan *c;
98
99 list_for_each_entry(c, &conn->chan_l, list) {
100 if (c->scid == cid)
101 return c;
102 }
103 return NULL;
104}
105
106/* Find channel with given SCID.
107 * Returns locked channel. */
108static struct l2cap_chan *l2cap_get_chan_by_scid(struct l2cap_conn *conn,
109 u16 cid)
110{
111 struct l2cap_chan *c;
112
113 mutex_lock(&conn->chan_lock);
114 c = __l2cap_get_chan_by_scid(conn, cid);
115 if (c)
116 l2cap_chan_lock(c);
117 mutex_unlock(&conn->chan_lock);
118
119 return c;
120}
121
122/* Find channel with given DCID.
123 * Returns locked channel.
124 */
125static struct l2cap_chan *l2cap_get_chan_by_dcid(struct l2cap_conn *conn,
126 u16 cid)
127{
128 struct l2cap_chan *c;
129
130 mutex_lock(&conn->chan_lock);
131 c = __l2cap_get_chan_by_dcid(conn, cid);
132 if (c)
133 l2cap_chan_lock(c);
134 mutex_unlock(&conn->chan_lock);
135
136 return c;
137}
138
139static struct l2cap_chan *__l2cap_get_chan_by_ident(struct l2cap_conn *conn,
140 u8 ident)
141{
142 struct l2cap_chan *c;
143
144 list_for_each_entry(c, &conn->chan_l, list) {
145 if (c->ident == ident)
146 return c;
147 }
148 return NULL;
149}
150
151static struct l2cap_chan *l2cap_get_chan_by_ident(struct l2cap_conn *conn,
152 u8 ident)
153{
154 struct l2cap_chan *c;
155
156 mutex_lock(&conn->chan_lock);
157 c = __l2cap_get_chan_by_ident(conn, ident);
158 if (c)
159 l2cap_chan_lock(c);
160 mutex_unlock(&conn->chan_lock);
161
162 return c;
163}
164
165static struct l2cap_chan *__l2cap_global_chan_by_addr(__le16 psm, bdaddr_t *src)
166{
167 struct l2cap_chan *c;
168
169 list_for_each_entry(c, &chan_list, global_l) {
170 if (c->sport == psm && !bacmp(&c->src, src))
171 return c;
172 }
173 return NULL;
174}
175
176int l2cap_add_psm(struct l2cap_chan *chan, bdaddr_t *src, __le16 psm)
177{
178 int err;
179
180 write_lock(&chan_list_lock);
181
182 if (psm && __l2cap_global_chan_by_addr(psm, src)) {
183 err = -EADDRINUSE;
184 goto done;
185 }
186
187 if (psm) {
188 chan->psm = psm;
189 chan->sport = psm;
190 err = 0;
191 } else {
192 u16 p;
193
194 err = -EINVAL;
195 for (p = 0x1001; p < 0x1100; p += 2)
196 if (!__l2cap_global_chan_by_addr(cpu_to_le16(p), src)) {
197 chan->psm = cpu_to_le16(p);
198 chan->sport = cpu_to_le16(p);
199 err = 0;
200 break;
201 }
202 }
203
204done:
205 write_unlock(&chan_list_lock);
206 return err;
207}
208
209int l2cap_add_scid(struct l2cap_chan *chan, __u16 scid)
210{
211 write_lock(&chan_list_lock);
212
213 chan->scid = scid;
214
215 write_unlock(&chan_list_lock);
216
217 return 0;
218}
219
220static u16 l2cap_alloc_cid(struct l2cap_conn *conn)
221{
222 u16 cid, dyn_end;
223
224 if (conn->hcon->type == LE_LINK)
225 dyn_end = L2CAP_CID_LE_DYN_END;
226 else
227 dyn_end = L2CAP_CID_DYN_END;
228
229 for (cid = L2CAP_CID_DYN_START; cid < dyn_end; cid++) {
230 if (!__l2cap_get_chan_by_scid(conn, cid))
231 return cid;
232 }
233
234 return 0;
235}
236
237static void l2cap_state_change(struct l2cap_chan *chan, int state)
238{
239 BT_DBG("chan %p %s -> %s", chan, state_to_string(chan->state),
240 state_to_string(state));
241
242 chan->state = state;
243 chan->ops->state_change(chan, state, 0);
244}
245
246static inline void l2cap_state_change_and_error(struct l2cap_chan *chan,
247 int state, int err)
248{
249 chan->state = state;
250 chan->ops->state_change(chan, chan->state, err);
251}
252
253static inline void l2cap_chan_set_err(struct l2cap_chan *chan, int err)
254{
255 chan->ops->state_change(chan, chan->state, err);
256}
257
258static void __set_retrans_timer(struct l2cap_chan *chan)
259{
260 if (!delayed_work_pending(&chan->monitor_timer) &&
261 chan->retrans_timeout) {
262 l2cap_set_timer(chan, &chan->retrans_timer,
263 msecs_to_jiffies(chan->retrans_timeout));
264 }
265}
266
267static void __set_monitor_timer(struct l2cap_chan *chan)
268{
269 __clear_retrans_timer(chan);
270 if (chan->monitor_timeout) {
271 l2cap_set_timer(chan, &chan->monitor_timer,
272 msecs_to_jiffies(chan->monitor_timeout));
273 }
274}
275
276static struct sk_buff *l2cap_ertm_seq_in_queue(struct sk_buff_head *head,
277 u16 seq)
278{
279 struct sk_buff *skb;
280
281 skb_queue_walk(head, skb) {
282 if (bt_cb(skb)->control.txseq == seq)
283 return skb;
284 }
285
286 return NULL;
287}
288
289/* ---- L2CAP sequence number lists ---- */
290
291/* For ERTM, ordered lists of sequence numbers must be tracked for
292 * SREJ requests that are received and for frames that are to be
293 * retransmitted. These seq_list functions implement a singly-linked
294 * list in an array, where membership in the list can also be checked
295 * in constant time. Items can also be added to the tail of the list
296 * and removed from the head in constant time, without further memory
297 * allocs or frees.
298 */
299
300static int l2cap_seq_list_init(struct l2cap_seq_list *seq_list, u16 size)
301{
302 size_t alloc_size, i;
303
304 /* Allocated size is a power of 2 to map sequence numbers
305 * (which may be up to 14 bits) in to a smaller array that is
306 * sized for the negotiated ERTM transmit windows.
307 */
308 alloc_size = roundup_pow_of_two(size);
309
310 seq_list->list = kmalloc(sizeof(u16) * alloc_size, GFP_KERNEL);
311 if (!seq_list->list)
312 return -ENOMEM;
313
314 seq_list->mask = alloc_size - 1;
315 seq_list->head = L2CAP_SEQ_LIST_CLEAR;
316 seq_list->tail = L2CAP_SEQ_LIST_CLEAR;
317 for (i = 0; i < alloc_size; i++)
318 seq_list->list[i] = L2CAP_SEQ_LIST_CLEAR;
319
320 return 0;
321}
322
323static inline void l2cap_seq_list_free(struct l2cap_seq_list *seq_list)
324{
325 kfree(seq_list->list);
326}
327
328static inline bool l2cap_seq_list_contains(struct l2cap_seq_list *seq_list,
329 u16 seq)
330{
331 /* Constant-time check for list membership */
332 return seq_list->list[seq & seq_list->mask] != L2CAP_SEQ_LIST_CLEAR;
333}
334
335static inline u16 l2cap_seq_list_pop(struct l2cap_seq_list *seq_list)
336{
337 u16 seq = seq_list->head;
338 u16 mask = seq_list->mask;
339
340 seq_list->head = seq_list->list[seq & mask];
341 seq_list->list[seq & mask] = L2CAP_SEQ_LIST_CLEAR;
342
343 if (seq_list->head == L2CAP_SEQ_LIST_TAIL) {
344 seq_list->head = L2CAP_SEQ_LIST_CLEAR;
345 seq_list->tail = L2CAP_SEQ_LIST_CLEAR;
346 }
347
348 return seq;
349}
350
351static void l2cap_seq_list_clear(struct l2cap_seq_list *seq_list)
352{
353 u16 i;
354
355 if (seq_list->head == L2CAP_SEQ_LIST_CLEAR)
356 return;
357
358 for (i = 0; i <= seq_list->mask; i++)
359 seq_list->list[i] = L2CAP_SEQ_LIST_CLEAR;
360
361 seq_list->head = L2CAP_SEQ_LIST_CLEAR;
362 seq_list->tail = L2CAP_SEQ_LIST_CLEAR;
363}
364
365static void l2cap_seq_list_append(struct l2cap_seq_list *seq_list, u16 seq)
366{
367 u16 mask = seq_list->mask;
368
369 /* All appends happen in constant time */
370
371 if (seq_list->list[seq & mask] != L2CAP_SEQ_LIST_CLEAR)
372 return;
373
374 if (seq_list->tail == L2CAP_SEQ_LIST_CLEAR)
375 seq_list->head = seq;
376 else
377 seq_list->list[seq_list->tail & mask] = seq;
378
379 seq_list->tail = seq;
380 seq_list->list[seq & mask] = L2CAP_SEQ_LIST_TAIL;
381}
382
383static void l2cap_chan_timeout(struct work_struct *work)
384{
385 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
386 chan_timer.work);
387 struct l2cap_conn *conn = chan->conn;
388 int reason;
389
390 BT_DBG("chan %p state %s", chan, state_to_string(chan->state));
391
392 mutex_lock(&conn->chan_lock);
393 l2cap_chan_lock(chan);
394
395 if (chan->state == BT_CONNECTED || chan->state == BT_CONFIG)
396 reason = ECONNREFUSED;
397 else if (chan->state == BT_CONNECT &&
398 chan->sec_level != BT_SECURITY_SDP)
399 reason = ECONNREFUSED;
400 else
401 reason = ETIMEDOUT;
402
403 l2cap_chan_close(chan, reason);
404
405 l2cap_chan_unlock(chan);
406
407 chan->ops->close(chan);
408 mutex_unlock(&conn->chan_lock);
409
410 l2cap_chan_put(chan);
411}
412
413struct l2cap_chan *l2cap_chan_create(void)
414{
415 struct l2cap_chan *chan;
416
417 chan = kzalloc(sizeof(*chan), GFP_ATOMIC);
418 if (!chan)
419 return NULL;
420
421 mutex_init(&chan->lock);
422
423 write_lock(&chan_list_lock);
424 list_add(&chan->global_l, &chan_list);
425 write_unlock(&chan_list_lock);
426
427 INIT_DELAYED_WORK(&chan->chan_timer, l2cap_chan_timeout);
428
429 chan->state = BT_OPEN;
430
431 kref_init(&chan->kref);
432
433 /* This flag is cleared in l2cap_chan_ready() */
434 set_bit(CONF_NOT_COMPLETE, &chan->conf_state);
435
436 BT_DBG("chan %p", chan);
437
438 return chan;
439}
440
441static void l2cap_chan_destroy(struct kref *kref)
442{
443 struct l2cap_chan *chan = container_of(kref, struct l2cap_chan, kref);
444
445 BT_DBG("chan %p", chan);
446
447 write_lock(&chan_list_lock);
448 list_del(&chan->global_l);
449 write_unlock(&chan_list_lock);
450
451 kfree(chan);
452}
453
454void l2cap_chan_hold(struct l2cap_chan *c)
455{
456 BT_DBG("chan %p orig refcnt %d", c, atomic_read(&c->kref.refcount));
457
458 kref_get(&c->kref);
459}
460
461void l2cap_chan_put(struct l2cap_chan *c)
462{
463 BT_DBG("chan %p orig refcnt %d", c, atomic_read(&c->kref.refcount));
464
465 kref_put(&c->kref, l2cap_chan_destroy);
466}
467
468void l2cap_chan_set_defaults(struct l2cap_chan *chan)
469{
470 chan->fcs = L2CAP_FCS_CRC16;
471 chan->max_tx = L2CAP_DEFAULT_MAX_TX;
472 chan->tx_win = L2CAP_DEFAULT_TX_WINDOW;
473 chan->tx_win_max = L2CAP_DEFAULT_TX_WINDOW;
474 chan->ack_win = L2CAP_DEFAULT_TX_WINDOW;
475 chan->sec_level = BT_SECURITY_LOW;
476
477 set_bit(FLAG_FORCE_ACTIVE, &chan->flags);
478}
479
480static void l2cap_le_flowctl_init(struct l2cap_chan *chan)
481{
482 chan->sdu = NULL;
483 chan->sdu_last_frag = NULL;
484 chan->sdu_len = 0;
485 chan->tx_credits = 0;
486 chan->rx_credits = le_max_credits;
487 chan->mps = min_t(u16, chan->imtu, le_default_mps);
488
489 skb_queue_head_init(&chan->tx_q);
490}
491
492void __l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan)
493{
494 BT_DBG("conn %p, psm 0x%2.2x, dcid 0x%4.4x", conn,
495 __le16_to_cpu(chan->psm), chan->dcid);
496
497 conn->disc_reason = HCI_ERROR_REMOTE_USER_TERM;
498
499 chan->conn = conn;
500
501 switch (chan->chan_type) {
502 case L2CAP_CHAN_CONN_ORIENTED:
503 /* Alloc CID for connection-oriented socket */
504 chan->scid = l2cap_alloc_cid(conn);
505 if (conn->hcon->type == ACL_LINK)
506 chan->omtu = L2CAP_DEFAULT_MTU;
507 break;
508
509 case L2CAP_CHAN_CONN_LESS:
510 /* Connectionless socket */
511 chan->scid = L2CAP_CID_CONN_LESS;
512 chan->dcid = L2CAP_CID_CONN_LESS;
513 chan->omtu = L2CAP_DEFAULT_MTU;
514 break;
515
516 case L2CAP_CHAN_FIXED:
517 /* Caller will set CID and CID specific MTU values */
518 break;
519
520 default:
521 /* Raw socket can send/recv signalling messages only */
522 chan->scid = L2CAP_CID_SIGNALING;
523 chan->dcid = L2CAP_CID_SIGNALING;
524 chan->omtu = L2CAP_DEFAULT_MTU;
525 }
526
527 chan->local_id = L2CAP_BESTEFFORT_ID;
528 chan->local_stype = L2CAP_SERV_BESTEFFORT;
529 chan->local_msdu = L2CAP_DEFAULT_MAX_SDU_SIZE;
530 chan->local_sdu_itime = L2CAP_DEFAULT_SDU_ITIME;
531 chan->local_acc_lat = L2CAP_DEFAULT_ACC_LAT;
532 chan->local_flush_to = L2CAP_EFS_DEFAULT_FLUSH_TO;
533
534 l2cap_chan_hold(chan);
535
536 hci_conn_hold(conn->hcon);
537
538 list_add(&chan->list, &conn->chan_l);
539}
540
541void l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan)
542{
543 mutex_lock(&conn->chan_lock);
544 __l2cap_chan_add(conn, chan);
545 mutex_unlock(&conn->chan_lock);
546}
547
548void l2cap_chan_del(struct l2cap_chan *chan, int err)
549{
550 struct l2cap_conn *conn = chan->conn;
551
552 __clear_chan_timer(chan);
553
554 BT_DBG("chan %p, conn %p, err %d", chan, conn, err);
555
556 if (conn) {
557 struct amp_mgr *mgr = conn->hcon->amp_mgr;
558 /* Delete from channel list */
559 list_del(&chan->list);
560
561 l2cap_chan_put(chan);
562
563 chan->conn = NULL;
564
565 if (chan->scid != L2CAP_CID_A2MP)
566 hci_conn_drop(conn->hcon);
567
568 if (mgr && mgr->bredr_chan == chan)
569 mgr->bredr_chan = NULL;
570 }
571
572 if (chan->hs_hchan) {
573 struct hci_chan *hs_hchan = chan->hs_hchan;
574
575 BT_DBG("chan %p disconnect hs_hchan %p", chan, hs_hchan);
576 amp_disconnect_logical_link(hs_hchan);
577 }
578
579 chan->ops->teardown(chan, err);
580
581 if (test_bit(CONF_NOT_COMPLETE, &chan->conf_state))
582 return;
583
584 switch(chan->mode) {
585 case L2CAP_MODE_BASIC:
586 break;
587
588 case L2CAP_MODE_LE_FLOWCTL:
589 skb_queue_purge(&chan->tx_q);
590 break;
591
592 case L2CAP_MODE_ERTM:
593 __clear_retrans_timer(chan);
594 __clear_monitor_timer(chan);
595 __clear_ack_timer(chan);
596
597 skb_queue_purge(&chan->srej_q);
598
599 l2cap_seq_list_free(&chan->srej_list);
600 l2cap_seq_list_free(&chan->retrans_list);
601
602 /* fall through */
603
604 case L2CAP_MODE_STREAMING:
605 skb_queue_purge(&chan->tx_q);
606 break;
607 }
608
609 return;
610}
611
612void l2cap_conn_update_id_addr(struct hci_conn *hcon)
613{
614 struct l2cap_conn *conn = hcon->l2cap_data;
615 struct l2cap_chan *chan;
616
617 mutex_lock(&conn->chan_lock);
618
619 list_for_each_entry(chan, &conn->chan_l, list) {
620 l2cap_chan_lock(chan);
621 bacpy(&chan->dst, &hcon->dst);
622 chan->dst_type = bdaddr_type(hcon, hcon->dst_type);
623 l2cap_chan_unlock(chan);
624 }
625
626 mutex_unlock(&conn->chan_lock);
627}
628
629static void l2cap_chan_le_connect_reject(struct l2cap_chan *chan)
630{
631 struct l2cap_conn *conn = chan->conn;
632 struct l2cap_le_conn_rsp rsp;
633 u16 result;
634
635 if (test_bit(FLAG_DEFER_SETUP, &chan->flags))
636 result = L2CAP_CR_AUTHORIZATION;
637 else
638 result = L2CAP_CR_BAD_PSM;
639
640 l2cap_state_change(chan, BT_DISCONN);
641
642 rsp.dcid = cpu_to_le16(chan->scid);
643 rsp.mtu = cpu_to_le16(chan->imtu);
644 rsp.mps = cpu_to_le16(chan->mps);
645 rsp.credits = cpu_to_le16(chan->rx_credits);
646 rsp.result = cpu_to_le16(result);
647
648 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CONN_RSP, sizeof(rsp),
649 &rsp);
650}
651
652static void l2cap_chan_connect_reject(struct l2cap_chan *chan)
653{
654 struct l2cap_conn *conn = chan->conn;
655 struct l2cap_conn_rsp rsp;
656 u16 result;
657
658 if (test_bit(FLAG_DEFER_SETUP, &chan->flags))
659 result = L2CAP_CR_SEC_BLOCK;
660 else
661 result = L2CAP_CR_BAD_PSM;
662
663 l2cap_state_change(chan, BT_DISCONN);
664
665 rsp.scid = cpu_to_le16(chan->dcid);
666 rsp.dcid = cpu_to_le16(chan->scid);
667 rsp.result = cpu_to_le16(result);
668 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
669
670 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP, sizeof(rsp), &rsp);
671}
672
673void l2cap_chan_close(struct l2cap_chan *chan, int reason)
674{
675 struct l2cap_conn *conn = chan->conn;
676
677 BT_DBG("chan %p state %s", chan, state_to_string(chan->state));
678
679 switch (chan->state) {
680 case BT_LISTEN:
681 chan->ops->teardown(chan, 0);
682 break;
683
684 case BT_CONNECTED:
685 case BT_CONFIG:
686 if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED) {
687 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
688 l2cap_send_disconn_req(chan, reason);
689 } else
690 l2cap_chan_del(chan, reason);
691 break;
692
693 case BT_CONNECT2:
694 if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED) {
695 if (conn->hcon->type == ACL_LINK)
696 l2cap_chan_connect_reject(chan);
697 else if (conn->hcon->type == LE_LINK)
698 l2cap_chan_le_connect_reject(chan);
699 }
700
701 l2cap_chan_del(chan, reason);
702 break;
703
704 case BT_CONNECT:
705 case BT_DISCONN:
706 l2cap_chan_del(chan, reason);
707 break;
708
709 default:
710 chan->ops->teardown(chan, 0);
711 break;
712 }
713}
714
715static inline u8 l2cap_get_auth_type(struct l2cap_chan *chan)
716{
717 switch (chan->chan_type) {
718 case L2CAP_CHAN_RAW:
719 switch (chan->sec_level) {
720 case BT_SECURITY_HIGH:
721 case BT_SECURITY_FIPS:
722 return HCI_AT_DEDICATED_BONDING_MITM;
723 case BT_SECURITY_MEDIUM:
724 return HCI_AT_DEDICATED_BONDING;
725 default:
726 return HCI_AT_NO_BONDING;
727 }
728 break;
729 case L2CAP_CHAN_CONN_LESS:
730 if (chan->psm == cpu_to_le16(L2CAP_PSM_3DSP)) {
731 if (chan->sec_level == BT_SECURITY_LOW)
732 chan->sec_level = BT_SECURITY_SDP;
733 }
734 if (chan->sec_level == BT_SECURITY_HIGH ||
735 chan->sec_level == BT_SECURITY_FIPS)
736 return HCI_AT_NO_BONDING_MITM;
737 else
738 return HCI_AT_NO_BONDING;
739 break;
740 case L2CAP_CHAN_CONN_ORIENTED:
741 if (chan->psm == cpu_to_le16(L2CAP_PSM_SDP)) {
742 if (chan->sec_level == BT_SECURITY_LOW)
743 chan->sec_level = BT_SECURITY_SDP;
744
745 if (chan->sec_level == BT_SECURITY_HIGH ||
746 chan->sec_level == BT_SECURITY_FIPS)
747 return HCI_AT_NO_BONDING_MITM;
748 else
749 return HCI_AT_NO_BONDING;
750 }
751 /* fall through */
752 default:
753 switch (chan->sec_level) {
754 case BT_SECURITY_HIGH:
755 case BT_SECURITY_FIPS:
756 return HCI_AT_GENERAL_BONDING_MITM;
757 case BT_SECURITY_MEDIUM:
758 return HCI_AT_GENERAL_BONDING;
759 default:
760 return HCI_AT_NO_BONDING;
761 }
762 break;
763 }
764}
765
766/* Service level security */
767int l2cap_chan_check_security(struct l2cap_chan *chan)
768{
769 struct l2cap_conn *conn = chan->conn;
770 __u8 auth_type;
771
772 if (conn->hcon->type == LE_LINK)
773 return smp_conn_security(conn->hcon, chan->sec_level);
774
775 auth_type = l2cap_get_auth_type(chan);
776
777 return hci_conn_security(conn->hcon, chan->sec_level, auth_type);
778}
779
780static u8 l2cap_get_ident(struct l2cap_conn *conn)
781{
782 u8 id;
783
784 /* Get next available identificator.
785 * 1 - 128 are used by kernel.
786 * 129 - 199 are reserved.
787 * 200 - 254 are used by utilities like l2ping, etc.
788 */
789
790 spin_lock(&conn->lock);
791
792 if (++conn->tx_ident > 128)
793 conn->tx_ident = 1;
794
795 id = conn->tx_ident;
796
797 spin_unlock(&conn->lock);
798
799 return id;
800}
801
802static void l2cap_send_cmd(struct l2cap_conn *conn, u8 ident, u8 code, u16 len,
803 void *data)
804{
805 struct sk_buff *skb = l2cap_build_cmd(conn, code, ident, len, data);
806 u8 flags;
807
808 BT_DBG("code 0x%2.2x", code);
809
810 if (!skb)
811 return;
812
813 if (lmp_no_flush_capable(conn->hcon->hdev))
814 flags = ACL_START_NO_FLUSH;
815 else
816 flags = ACL_START;
817
818 bt_cb(skb)->force_active = BT_POWER_FORCE_ACTIVE_ON;
819 skb->priority = HCI_PRIO_MAX;
820
821 hci_send_acl(conn->hchan, skb, flags);
822}
823
824static bool __chan_is_moving(struct l2cap_chan *chan)
825{
826 return chan->move_state != L2CAP_MOVE_STABLE &&
827 chan->move_state != L2CAP_MOVE_WAIT_PREPARE;
828}
829
830static void l2cap_do_send(struct l2cap_chan *chan, struct sk_buff *skb)
831{
832 struct hci_conn *hcon = chan->conn->hcon;
833 u16 flags;
834
835 BT_DBG("chan %p, skb %p len %d priority %u", chan, skb, skb->len,
836 skb->priority);
837
838 if (chan->hs_hcon && !__chan_is_moving(chan)) {
839 if (chan->hs_hchan)
840 hci_send_acl(chan->hs_hchan, skb, ACL_COMPLETE);
841 else
842 kfree_skb(skb);
843
844 return;
845 }
846
847 if (!test_bit(FLAG_FLUSHABLE, &chan->flags) &&
848 lmp_no_flush_capable(hcon->hdev))
849 flags = ACL_START_NO_FLUSH;
850 else
851 flags = ACL_START;
852
853 bt_cb(skb)->force_active = test_bit(FLAG_FORCE_ACTIVE, &chan->flags);
854 hci_send_acl(chan->conn->hchan, skb, flags);
855}
856
857static void __unpack_enhanced_control(u16 enh, struct l2cap_ctrl *control)
858{
859 control->reqseq = (enh & L2CAP_CTRL_REQSEQ) >> L2CAP_CTRL_REQSEQ_SHIFT;
860 control->final = (enh & L2CAP_CTRL_FINAL) >> L2CAP_CTRL_FINAL_SHIFT;
861
862 if (enh & L2CAP_CTRL_FRAME_TYPE) {
863 /* S-Frame */
864 control->sframe = 1;
865 control->poll = (enh & L2CAP_CTRL_POLL) >> L2CAP_CTRL_POLL_SHIFT;
866 control->super = (enh & L2CAP_CTRL_SUPERVISE) >> L2CAP_CTRL_SUPER_SHIFT;
867
868 control->sar = 0;
869 control->txseq = 0;
870 } else {
871 /* I-Frame */
872 control->sframe = 0;
873 control->sar = (enh & L2CAP_CTRL_SAR) >> L2CAP_CTRL_SAR_SHIFT;
874 control->txseq = (enh & L2CAP_CTRL_TXSEQ) >> L2CAP_CTRL_TXSEQ_SHIFT;
875
876 control->poll = 0;
877 control->super = 0;
878 }
879}
880
881static void __unpack_extended_control(u32 ext, struct l2cap_ctrl *control)
882{
883 control->reqseq = (ext & L2CAP_EXT_CTRL_REQSEQ) >> L2CAP_EXT_CTRL_REQSEQ_SHIFT;
884 control->final = (ext & L2CAP_EXT_CTRL_FINAL) >> L2CAP_EXT_CTRL_FINAL_SHIFT;
885
886 if (ext & L2CAP_EXT_CTRL_FRAME_TYPE) {
887 /* S-Frame */
888 control->sframe = 1;
889 control->poll = (ext & L2CAP_EXT_CTRL_POLL) >> L2CAP_EXT_CTRL_POLL_SHIFT;
890 control->super = (ext & L2CAP_EXT_CTRL_SUPERVISE) >> L2CAP_EXT_CTRL_SUPER_SHIFT;
891
892 control->sar = 0;
893 control->txseq = 0;
894 } else {
895 /* I-Frame */
896 control->sframe = 0;
897 control->sar = (ext & L2CAP_EXT_CTRL_SAR) >> L2CAP_EXT_CTRL_SAR_SHIFT;
898 control->txseq = (ext & L2CAP_EXT_CTRL_TXSEQ) >> L2CAP_EXT_CTRL_TXSEQ_SHIFT;
899
900 control->poll = 0;
901 control->super = 0;
902 }
903}
904
905static inline void __unpack_control(struct l2cap_chan *chan,
906 struct sk_buff *skb)
907{
908 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) {
909 __unpack_extended_control(get_unaligned_le32(skb->data),
910 &bt_cb(skb)->control);
911 skb_pull(skb, L2CAP_EXT_CTRL_SIZE);
912 } else {
913 __unpack_enhanced_control(get_unaligned_le16(skb->data),
914 &bt_cb(skb)->control);
915 skb_pull(skb, L2CAP_ENH_CTRL_SIZE);
916 }
917}
918
919static u32 __pack_extended_control(struct l2cap_ctrl *control)
920{
921 u32 packed;
922
923 packed = control->reqseq << L2CAP_EXT_CTRL_REQSEQ_SHIFT;
924 packed |= control->final << L2CAP_EXT_CTRL_FINAL_SHIFT;
925
926 if (control->sframe) {
927 packed |= control->poll << L2CAP_EXT_CTRL_POLL_SHIFT;
928 packed |= control->super << L2CAP_EXT_CTRL_SUPER_SHIFT;
929 packed |= L2CAP_EXT_CTRL_FRAME_TYPE;
930 } else {
931 packed |= control->sar << L2CAP_EXT_CTRL_SAR_SHIFT;
932 packed |= control->txseq << L2CAP_EXT_CTRL_TXSEQ_SHIFT;
933 }
934
935 return packed;
936}
937
938static u16 __pack_enhanced_control(struct l2cap_ctrl *control)
939{
940 u16 packed;
941
942 packed = control->reqseq << L2CAP_CTRL_REQSEQ_SHIFT;
943 packed |= control->final << L2CAP_CTRL_FINAL_SHIFT;
944
945 if (control->sframe) {
946 packed |= control->poll << L2CAP_CTRL_POLL_SHIFT;
947 packed |= control->super << L2CAP_CTRL_SUPER_SHIFT;
948 packed |= L2CAP_CTRL_FRAME_TYPE;
949 } else {
950 packed |= control->sar << L2CAP_CTRL_SAR_SHIFT;
951 packed |= control->txseq << L2CAP_CTRL_TXSEQ_SHIFT;
952 }
953
954 return packed;
955}
956
957static inline void __pack_control(struct l2cap_chan *chan,
958 struct l2cap_ctrl *control,
959 struct sk_buff *skb)
960{
961 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) {
962 put_unaligned_le32(__pack_extended_control(control),
963 skb->data + L2CAP_HDR_SIZE);
964 } else {
965 put_unaligned_le16(__pack_enhanced_control(control),
966 skb->data + L2CAP_HDR_SIZE);
967 }
968}
969
970static inline unsigned int __ertm_hdr_size(struct l2cap_chan *chan)
971{
972 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
973 return L2CAP_EXT_HDR_SIZE;
974 else
975 return L2CAP_ENH_HDR_SIZE;
976}
977
978static struct sk_buff *l2cap_create_sframe_pdu(struct l2cap_chan *chan,
979 u32 control)
980{
981 struct sk_buff *skb;
982 struct l2cap_hdr *lh;
983 int hlen = __ertm_hdr_size(chan);
984
985 if (chan->fcs == L2CAP_FCS_CRC16)
986 hlen += L2CAP_FCS_SIZE;
987
988 skb = bt_skb_alloc(hlen, GFP_KERNEL);
989
990 if (!skb)
991 return ERR_PTR(-ENOMEM);
992
993 lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
994 lh->len = cpu_to_le16(hlen - L2CAP_HDR_SIZE);
995 lh->cid = cpu_to_le16(chan->dcid);
996
997 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
998 put_unaligned_le32(control, skb_put(skb, L2CAP_EXT_CTRL_SIZE));
999 else
1000 put_unaligned_le16(control, skb_put(skb, L2CAP_ENH_CTRL_SIZE));
1001
1002 if (chan->fcs == L2CAP_FCS_CRC16) {
1003 u16 fcs = crc16(0, (u8 *)skb->data, skb->len);
1004 put_unaligned_le16(fcs, skb_put(skb, L2CAP_FCS_SIZE));
1005 }
1006
1007 skb->priority = HCI_PRIO_MAX;
1008 return skb;
1009}
1010
1011static void l2cap_send_sframe(struct l2cap_chan *chan,
1012 struct l2cap_ctrl *control)
1013{
1014 struct sk_buff *skb;
1015 u32 control_field;
1016
1017 BT_DBG("chan %p, control %p", chan, control);
1018
1019 if (!control->sframe)
1020 return;
1021
1022 if (__chan_is_moving(chan))
1023 return;
1024
1025 if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state) &&
1026 !control->poll)
1027 control->final = 1;
1028
1029 if (control->super == L2CAP_SUPER_RR)
1030 clear_bit(CONN_RNR_SENT, &chan->conn_state);
1031 else if (control->super == L2CAP_SUPER_RNR)
1032 set_bit(CONN_RNR_SENT, &chan->conn_state);
1033
1034 if (control->super != L2CAP_SUPER_SREJ) {
1035 chan->last_acked_seq = control->reqseq;
1036 __clear_ack_timer(chan);
1037 }
1038
1039 BT_DBG("reqseq %d, final %d, poll %d, super %d", control->reqseq,
1040 control->final, control->poll, control->super);
1041
1042 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
1043 control_field = __pack_extended_control(control);
1044 else
1045 control_field = __pack_enhanced_control(control);
1046
1047 skb = l2cap_create_sframe_pdu(chan, control_field);
1048 if (!IS_ERR(skb))
1049 l2cap_do_send(chan, skb);
1050}
1051
1052static void l2cap_send_rr_or_rnr(struct l2cap_chan *chan, bool poll)
1053{
1054 struct l2cap_ctrl control;
1055
1056 BT_DBG("chan %p, poll %d", chan, poll);
1057
1058 memset(&control, 0, sizeof(control));
1059 control.sframe = 1;
1060 control.poll = poll;
1061
1062 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state))
1063 control.super = L2CAP_SUPER_RNR;
1064 else
1065 control.super = L2CAP_SUPER_RR;
1066
1067 control.reqseq = chan->buffer_seq;
1068 l2cap_send_sframe(chan, &control);
1069}
1070
1071static inline int __l2cap_no_conn_pending(struct l2cap_chan *chan)
1072{
1073 return !test_bit(CONF_CONNECT_PEND, &chan->conf_state);
1074}
1075
1076static bool __amp_capable(struct l2cap_chan *chan)
1077{
1078 struct l2cap_conn *conn = chan->conn;
1079 struct hci_dev *hdev;
1080 bool amp_available = false;
1081
1082 if (!conn->hs_enabled)
1083 return false;
1084
1085 if (!(conn->fixed_chan_mask & L2CAP_FC_A2MP))
1086 return false;
1087
1088 read_lock(&hci_dev_list_lock);
1089 list_for_each_entry(hdev, &hci_dev_list, list) {
1090 if (hdev->amp_type != AMP_TYPE_BREDR &&
1091 test_bit(HCI_UP, &hdev->flags)) {
1092 amp_available = true;
1093 break;
1094 }
1095 }
1096 read_unlock(&hci_dev_list_lock);
1097
1098 if (chan->chan_policy == BT_CHANNEL_POLICY_AMP_PREFERRED)
1099 return amp_available;
1100
1101 return false;
1102}
1103
1104static bool l2cap_check_efs(struct l2cap_chan *chan)
1105{
1106 /* Check EFS parameters */
1107 return true;
1108}
1109
1110void l2cap_send_conn_req(struct l2cap_chan *chan)
1111{
1112 struct l2cap_conn *conn = chan->conn;
1113 struct l2cap_conn_req req;
1114
1115 req.scid = cpu_to_le16(chan->scid);
1116 req.psm = chan->psm;
1117
1118 chan->ident = l2cap_get_ident(conn);
1119
1120 set_bit(CONF_CONNECT_PEND, &chan->conf_state);
1121
1122 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_REQ, sizeof(req), &req);
1123}
1124
1125static void l2cap_send_create_chan_req(struct l2cap_chan *chan, u8 amp_id)
1126{
1127 struct l2cap_create_chan_req req;
1128 req.scid = cpu_to_le16(chan->scid);
1129 req.psm = chan->psm;
1130 req.amp_id = amp_id;
1131
1132 chan->ident = l2cap_get_ident(chan->conn);
1133
1134 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_CREATE_CHAN_REQ,
1135 sizeof(req), &req);
1136}
1137
1138static void l2cap_move_setup(struct l2cap_chan *chan)
1139{
1140 struct sk_buff *skb;
1141
1142 BT_DBG("chan %p", chan);
1143
1144 if (chan->mode != L2CAP_MODE_ERTM)
1145 return;
1146
1147 __clear_retrans_timer(chan);
1148 __clear_monitor_timer(chan);
1149 __clear_ack_timer(chan);
1150
1151 chan->retry_count = 0;
1152 skb_queue_walk(&chan->tx_q, skb) {
1153 if (bt_cb(skb)->control.retries)
1154 bt_cb(skb)->control.retries = 1;
1155 else
1156 break;
1157 }
1158
1159 chan->expected_tx_seq = chan->buffer_seq;
1160
1161 clear_bit(CONN_REJ_ACT, &chan->conn_state);
1162 clear_bit(CONN_SREJ_ACT, &chan->conn_state);
1163 l2cap_seq_list_clear(&chan->retrans_list);
1164 l2cap_seq_list_clear(&chan->srej_list);
1165 skb_queue_purge(&chan->srej_q);
1166
1167 chan->tx_state = L2CAP_TX_STATE_XMIT;
1168 chan->rx_state = L2CAP_RX_STATE_MOVE;
1169
1170 set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
1171}
1172
1173static void l2cap_move_done(struct l2cap_chan *chan)
1174{
1175 u8 move_role = chan->move_role;
1176 BT_DBG("chan %p", chan);
1177
1178 chan->move_state = L2CAP_MOVE_STABLE;
1179 chan->move_role = L2CAP_MOVE_ROLE_NONE;
1180
1181 if (chan->mode != L2CAP_MODE_ERTM)
1182 return;
1183
1184 switch (move_role) {
1185 case L2CAP_MOVE_ROLE_INITIATOR:
1186 l2cap_tx(chan, NULL, NULL, L2CAP_EV_EXPLICIT_POLL);
1187 chan->rx_state = L2CAP_RX_STATE_WAIT_F;
1188 break;
1189 case L2CAP_MOVE_ROLE_RESPONDER:
1190 chan->rx_state = L2CAP_RX_STATE_WAIT_P;
1191 break;
1192 }
1193}
1194
1195static void l2cap_chan_ready(struct l2cap_chan *chan)
1196{
1197 /* This clears all conf flags, including CONF_NOT_COMPLETE */
1198 chan->conf_state = 0;
1199 __clear_chan_timer(chan);
1200
1201 if (chan->mode == L2CAP_MODE_LE_FLOWCTL && !chan->tx_credits)
1202 chan->ops->suspend(chan);
1203
1204 chan->state = BT_CONNECTED;
1205
1206 chan->ops->ready(chan);
1207}
1208
1209static void l2cap_le_connect(struct l2cap_chan *chan)
1210{
1211 struct l2cap_conn *conn = chan->conn;
1212 struct l2cap_le_conn_req req;
1213
1214 if (test_and_set_bit(FLAG_LE_CONN_REQ_SENT, &chan->flags))
1215 return;
1216
1217 req.psm = chan->psm;
1218 req.scid = cpu_to_le16(chan->scid);
1219 req.mtu = cpu_to_le16(chan->imtu);
1220 req.mps = cpu_to_le16(chan->mps);
1221 req.credits = cpu_to_le16(chan->rx_credits);
1222
1223 chan->ident = l2cap_get_ident(conn);
1224
1225 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CONN_REQ,
1226 sizeof(req), &req);
1227}
1228
1229static void l2cap_le_start(struct l2cap_chan *chan)
1230{
1231 struct l2cap_conn *conn = chan->conn;
1232
1233 if (!smp_conn_security(conn->hcon, chan->sec_level))
1234 return;
1235
1236 if (!chan->psm) {
1237 l2cap_chan_ready(chan);
1238 return;
1239 }
1240
1241 if (chan->state == BT_CONNECT)
1242 l2cap_le_connect(chan);
1243}
1244
1245static void l2cap_start_connection(struct l2cap_chan *chan)
1246{
1247 if (__amp_capable(chan)) {
1248 BT_DBG("chan %p AMP capable: discover AMPs", chan);
1249 a2mp_discover_amp(chan);
1250 } else if (chan->conn->hcon->type == LE_LINK) {
1251 l2cap_le_start(chan);
1252 } else {
1253 l2cap_send_conn_req(chan);
1254 }
1255}
1256
1257static void l2cap_do_start(struct l2cap_chan *chan)
1258{
1259 struct l2cap_conn *conn = chan->conn;
1260
1261 if (conn->hcon->type == LE_LINK) {
1262 l2cap_le_start(chan);
1263 return;
1264 }
1265
1266 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT) {
1267 if (!(conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE))
1268 return;
1269
1270 if (l2cap_chan_check_security(chan) &&
1271 __l2cap_no_conn_pending(chan)) {
1272 l2cap_start_connection(chan);
1273 }
1274 } else {
1275 struct l2cap_info_req req;
1276 req.type = cpu_to_le16(L2CAP_IT_FEAT_MASK);
1277
1278 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_SENT;
1279 conn->info_ident = l2cap_get_ident(conn);
1280
1281 schedule_delayed_work(&conn->info_timer, L2CAP_INFO_TIMEOUT);
1282
1283 l2cap_send_cmd(conn, conn->info_ident, L2CAP_INFO_REQ,
1284 sizeof(req), &req);
1285 }
1286}
1287
1288static inline int l2cap_mode_supported(__u8 mode, __u32 feat_mask)
1289{
1290 u32 local_feat_mask = l2cap_feat_mask;
1291 if (!disable_ertm)
1292 local_feat_mask |= L2CAP_FEAT_ERTM | L2CAP_FEAT_STREAMING;
1293
1294 switch (mode) {
1295 case L2CAP_MODE_ERTM:
1296 return L2CAP_FEAT_ERTM & feat_mask & local_feat_mask;
1297 case L2CAP_MODE_STREAMING:
1298 return L2CAP_FEAT_STREAMING & feat_mask & local_feat_mask;
1299 default:
1300 return 0x00;
1301 }
1302}
1303
1304static void l2cap_send_disconn_req(struct l2cap_chan *chan, int err)
1305{
1306 struct l2cap_conn *conn = chan->conn;
1307 struct l2cap_disconn_req req;
1308
1309 if (!conn)
1310 return;
1311
1312 if (chan->mode == L2CAP_MODE_ERTM && chan->state == BT_CONNECTED) {
1313 __clear_retrans_timer(chan);
1314 __clear_monitor_timer(chan);
1315 __clear_ack_timer(chan);
1316 }
1317
1318 if (chan->scid == L2CAP_CID_A2MP) {
1319 l2cap_state_change(chan, BT_DISCONN);
1320 return;
1321 }
1322
1323 req.dcid = cpu_to_le16(chan->dcid);
1324 req.scid = cpu_to_le16(chan->scid);
1325 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_DISCONN_REQ,
1326 sizeof(req), &req);
1327
1328 l2cap_state_change_and_error(chan, BT_DISCONN, err);
1329}
1330
1331/* ---- L2CAP connections ---- */
1332static void l2cap_conn_start(struct l2cap_conn *conn)
1333{
1334 struct l2cap_chan *chan, *tmp;
1335
1336 BT_DBG("conn %p", conn);
1337
1338 mutex_lock(&conn->chan_lock);
1339
1340 list_for_each_entry_safe(chan, tmp, &conn->chan_l, list) {
1341 l2cap_chan_lock(chan);
1342
1343 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
1344 l2cap_chan_unlock(chan);
1345 continue;
1346 }
1347
1348 if (chan->state == BT_CONNECT) {
1349 if (!l2cap_chan_check_security(chan) ||
1350 !__l2cap_no_conn_pending(chan)) {
1351 l2cap_chan_unlock(chan);
1352 continue;
1353 }
1354
1355 if (!l2cap_mode_supported(chan->mode, conn->feat_mask)
1356 && test_bit(CONF_STATE2_DEVICE,
1357 &chan->conf_state)) {
1358 l2cap_chan_close(chan, ECONNRESET);
1359 l2cap_chan_unlock(chan);
1360 continue;
1361 }
1362
1363 l2cap_start_connection(chan);
1364
1365 } else if (chan->state == BT_CONNECT2) {
1366 struct l2cap_conn_rsp rsp;
1367 char buf[128];
1368 rsp.scid = cpu_to_le16(chan->dcid);
1369 rsp.dcid = cpu_to_le16(chan->scid);
1370
1371 if (l2cap_chan_check_security(chan)) {
1372 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
1373 rsp.result = cpu_to_le16(L2CAP_CR_PEND);
1374 rsp.status = cpu_to_le16(L2CAP_CS_AUTHOR_PEND);
1375 chan->ops->defer(chan);
1376
1377 } else {
1378 l2cap_state_change(chan, BT_CONFIG);
1379 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
1380 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
1381 }
1382 } else {
1383 rsp.result = cpu_to_le16(L2CAP_CR_PEND);
1384 rsp.status = cpu_to_le16(L2CAP_CS_AUTHEN_PEND);
1385 }
1386
1387 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP,
1388 sizeof(rsp), &rsp);
1389
1390 if (test_bit(CONF_REQ_SENT, &chan->conf_state) ||
1391 rsp.result != L2CAP_CR_SUCCESS) {
1392 l2cap_chan_unlock(chan);
1393 continue;
1394 }
1395
1396 set_bit(CONF_REQ_SENT, &chan->conf_state);
1397 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
1398 l2cap_build_conf_req(chan, buf), buf);
1399 chan->num_conf_req++;
1400 }
1401
1402 l2cap_chan_unlock(chan);
1403 }
1404
1405 mutex_unlock(&conn->chan_lock);
1406}
1407
1408/* Find socket with cid and source/destination bdaddr.
1409 * Returns closest match, locked.
1410 */
1411static struct l2cap_chan *l2cap_global_chan_by_scid(int state, u16 cid,
1412 bdaddr_t *src,
1413 bdaddr_t *dst)
1414{
1415 struct l2cap_chan *c, *c1 = NULL;
1416
1417 read_lock(&chan_list_lock);
1418
1419 list_for_each_entry(c, &chan_list, global_l) {
1420 if (state && c->state != state)
1421 continue;
1422
1423 if (c->scid == cid) {
1424 int src_match, dst_match;
1425 int src_any, dst_any;
1426
1427 /* Exact match. */
1428 src_match = !bacmp(&c->src, src);
1429 dst_match = !bacmp(&c->dst, dst);
1430 if (src_match && dst_match) {
1431 read_unlock(&chan_list_lock);
1432 return c;
1433 }
1434
1435 /* Closest match */
1436 src_any = !bacmp(&c->src, BDADDR_ANY);
1437 dst_any = !bacmp(&c->dst, BDADDR_ANY);
1438 if ((src_match && dst_any) || (src_any && dst_match) ||
1439 (src_any && dst_any))
1440 c1 = c;
1441 }
1442 }
1443
1444 read_unlock(&chan_list_lock);
1445
1446 return c1;
1447}
1448
1449static void l2cap_le_conn_ready(struct l2cap_conn *conn)
1450{
1451 struct hci_conn *hcon = conn->hcon;
1452 struct l2cap_chan *chan, *pchan;
1453 u8 dst_type;
1454
1455 BT_DBG("");
1456
1457 bt_6lowpan_add_conn(conn);
1458
1459 /* Check if we have socket listening on cid */
1460 pchan = l2cap_global_chan_by_scid(BT_LISTEN, L2CAP_CID_ATT,
1461 &hcon->src, &hcon->dst);
1462 if (!pchan)
1463 return;
1464
1465 /* Client ATT sockets should override the server one */
1466 if (__l2cap_get_chan_by_dcid(conn, L2CAP_CID_ATT))
1467 return;
1468
1469 dst_type = bdaddr_type(hcon, hcon->dst_type);
1470
1471 /* If device is blocked, do not create a channel for it */
1472 if (hci_blacklist_lookup(hcon->hdev, &hcon->dst, dst_type))
1473 return;
1474
1475 l2cap_chan_lock(pchan);
1476
1477 chan = pchan->ops->new_connection(pchan);
1478 if (!chan)
1479 goto clean;
1480
1481 bacpy(&chan->src, &hcon->src);
1482 bacpy(&chan->dst, &hcon->dst);
1483 chan->src_type = bdaddr_type(hcon, hcon->src_type);
1484 chan->dst_type = dst_type;
1485
1486 __l2cap_chan_add(conn, chan);
1487
1488clean:
1489 l2cap_chan_unlock(pchan);
1490}
1491
1492static void l2cap_conn_ready(struct l2cap_conn *conn)
1493{
1494 struct l2cap_chan *chan;
1495 struct hci_conn *hcon = conn->hcon;
1496
1497 BT_DBG("conn %p", conn);
1498
1499 /* For outgoing pairing which doesn't necessarily have an
1500 * associated socket (e.g. mgmt_pair_device).
1501 */
1502 if (hcon->out && hcon->type == LE_LINK)
1503 smp_conn_security(hcon, hcon->pending_sec_level);
1504
1505 mutex_lock(&conn->chan_lock);
1506
1507 if (hcon->type == LE_LINK)
1508 l2cap_le_conn_ready(conn);
1509
1510 list_for_each_entry(chan, &conn->chan_l, list) {
1511
1512 l2cap_chan_lock(chan);
1513
1514 if (chan->scid == L2CAP_CID_A2MP) {
1515 l2cap_chan_unlock(chan);
1516 continue;
1517 }
1518
1519 if (hcon->type == LE_LINK) {
1520 l2cap_le_start(chan);
1521 } else if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
1522 l2cap_chan_ready(chan);
1523
1524 } else if (chan->state == BT_CONNECT) {
1525 l2cap_do_start(chan);
1526 }
1527
1528 l2cap_chan_unlock(chan);
1529 }
1530
1531 mutex_unlock(&conn->chan_lock);
1532
1533 queue_work(hcon->hdev->workqueue, &conn->pending_rx_work);
1534}
1535
1536/* Notify sockets that we cannot guaranty reliability anymore */
1537static void l2cap_conn_unreliable(struct l2cap_conn *conn, int err)
1538{
1539 struct l2cap_chan *chan;
1540
1541 BT_DBG("conn %p", conn);
1542
1543 mutex_lock(&conn->chan_lock);
1544
1545 list_for_each_entry(chan, &conn->chan_l, list) {
1546 if (test_bit(FLAG_FORCE_RELIABLE, &chan->flags))
1547 l2cap_chan_set_err(chan, err);
1548 }
1549
1550 mutex_unlock(&conn->chan_lock);
1551}
1552
1553static void l2cap_info_timeout(struct work_struct *work)
1554{
1555 struct l2cap_conn *conn = container_of(work, struct l2cap_conn,
1556 info_timer.work);
1557
1558 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
1559 conn->info_ident = 0;
1560
1561 l2cap_conn_start(conn);
1562}
1563
1564/*
1565 * l2cap_user
1566 * External modules can register l2cap_user objects on l2cap_conn. The ->probe
1567 * callback is called during registration. The ->remove callback is called
1568 * during unregistration.
1569 * An l2cap_user object can either be explicitly unregistered or when the
1570 * underlying l2cap_conn object is deleted. This guarantees that l2cap->hcon,
1571 * l2cap->hchan, .. are valid as long as the remove callback hasn't been called.
1572 * External modules must own a reference to the l2cap_conn object if they intend
1573 * to call l2cap_unregister_user(). The l2cap_conn object might get destroyed at
1574 * any time if they don't.
1575 */
1576
1577int l2cap_register_user(struct l2cap_conn *conn, struct l2cap_user *user)
1578{
1579 struct hci_dev *hdev = conn->hcon->hdev;
1580 int ret;
1581
1582 /* We need to check whether l2cap_conn is registered. If it is not, we
1583 * must not register the l2cap_user. l2cap_conn_del() is unregisters
1584 * l2cap_conn objects, but doesn't provide its own locking. Instead, it
1585 * relies on the parent hci_conn object to be locked. This itself relies
1586 * on the hci_dev object to be locked. So we must lock the hci device
1587 * here, too. */
1588
1589 hci_dev_lock(hdev);
1590
1591 if (user->list.next || user->list.prev) {
1592 ret = -EINVAL;
1593 goto out_unlock;
1594 }
1595
1596 /* conn->hchan is NULL after l2cap_conn_del() was called */
1597 if (!conn->hchan) {
1598 ret = -ENODEV;
1599 goto out_unlock;
1600 }
1601
1602 ret = user->probe(conn, user);
1603 if (ret)
1604 goto out_unlock;
1605
1606 list_add(&user->list, &conn->users);
1607 ret = 0;
1608
1609out_unlock:
1610 hci_dev_unlock(hdev);
1611 return ret;
1612}
1613EXPORT_SYMBOL(l2cap_register_user);
1614
1615void l2cap_unregister_user(struct l2cap_conn *conn, struct l2cap_user *user)
1616{
1617 struct hci_dev *hdev = conn->hcon->hdev;
1618
1619 hci_dev_lock(hdev);
1620
1621 if (!user->list.next || !user->list.prev)
1622 goto out_unlock;
1623
1624 list_del(&user->list);
1625 user->list.next = NULL;
1626 user->list.prev = NULL;
1627 user->remove(conn, user);
1628
1629out_unlock:
1630 hci_dev_unlock(hdev);
1631}
1632EXPORT_SYMBOL(l2cap_unregister_user);
1633
1634static void l2cap_unregister_all_users(struct l2cap_conn *conn)
1635{
1636 struct l2cap_user *user;
1637
1638 while (!list_empty(&conn->users)) {
1639 user = list_first_entry(&conn->users, struct l2cap_user, list);
1640 list_del(&user->list);
1641 user->list.next = NULL;
1642 user->list.prev = NULL;
1643 user->remove(conn, user);
1644 }
1645}
1646
1647static void l2cap_conn_del(struct hci_conn *hcon, int err)
1648{
1649 struct l2cap_conn *conn = hcon->l2cap_data;
1650 struct l2cap_chan *chan, *l;
1651
1652 if (!conn)
1653 return;
1654
1655 BT_DBG("hcon %p conn %p, err %d", hcon, conn, err);
1656
1657 kfree_skb(conn->rx_skb);
1658
1659 skb_queue_purge(&conn->pending_rx);
1660 flush_work(&conn->pending_rx_work);
1661
1662 l2cap_unregister_all_users(conn);
1663
1664 mutex_lock(&conn->chan_lock);
1665
1666 /* Kill channels */
1667 list_for_each_entry_safe(chan, l, &conn->chan_l, list) {
1668 l2cap_chan_hold(chan);
1669 l2cap_chan_lock(chan);
1670
1671 l2cap_chan_del(chan, err);
1672
1673 l2cap_chan_unlock(chan);
1674
1675 chan->ops->close(chan);
1676 l2cap_chan_put(chan);
1677 }
1678
1679 mutex_unlock(&conn->chan_lock);
1680
1681 hci_chan_del(conn->hchan);
1682
1683 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT)
1684 cancel_delayed_work_sync(&conn->info_timer);
1685
1686 if (test_and_clear_bit(HCI_CONN_LE_SMP_PEND, &hcon->flags)) {
1687 cancel_delayed_work_sync(&conn->security_timer);
1688 smp_chan_destroy(conn);
1689 }
1690
1691 hcon->l2cap_data = NULL;
1692 conn->hchan = NULL;
1693 l2cap_conn_put(conn);
1694}
1695
1696static void security_timeout(struct work_struct *work)
1697{
1698 struct l2cap_conn *conn = container_of(work, struct l2cap_conn,
1699 security_timer.work);
1700
1701 BT_DBG("conn %p", conn);
1702
1703 if (test_and_clear_bit(HCI_CONN_LE_SMP_PEND, &conn->hcon->flags)) {
1704 smp_chan_destroy(conn);
1705 l2cap_conn_del(conn->hcon, ETIMEDOUT);
1706 }
1707}
1708
1709static void l2cap_conn_free(struct kref *ref)
1710{
1711 struct l2cap_conn *conn = container_of(ref, struct l2cap_conn, ref);
1712
1713 hci_conn_put(conn->hcon);
1714 kfree(conn);
1715}
1716
1717void l2cap_conn_get(struct l2cap_conn *conn)
1718{
1719 kref_get(&conn->ref);
1720}
1721EXPORT_SYMBOL(l2cap_conn_get);
1722
1723void l2cap_conn_put(struct l2cap_conn *conn)
1724{
1725 kref_put(&conn->ref, l2cap_conn_free);
1726}
1727EXPORT_SYMBOL(l2cap_conn_put);
1728
1729/* ---- Socket interface ---- */
1730
1731/* Find socket with psm and source / destination bdaddr.
1732 * Returns closest match.
1733 */
1734static struct l2cap_chan *l2cap_global_chan_by_psm(int state, __le16 psm,
1735 bdaddr_t *src,
1736 bdaddr_t *dst,
1737 u8 link_type)
1738{
1739 struct l2cap_chan *c, *c1 = NULL;
1740
1741 read_lock(&chan_list_lock);
1742
1743 list_for_each_entry(c, &chan_list, global_l) {
1744 if (state && c->state != state)
1745 continue;
1746
1747 if (link_type == ACL_LINK && c->src_type != BDADDR_BREDR)
1748 continue;
1749
1750 if (link_type == LE_LINK && c->src_type == BDADDR_BREDR)
1751 continue;
1752
1753 if (c->psm == psm) {
1754 int src_match, dst_match;
1755 int src_any, dst_any;
1756
1757 /* Exact match. */
1758 src_match = !bacmp(&c->src, src);
1759 dst_match = !bacmp(&c->dst, dst);
1760 if (src_match && dst_match) {
1761 read_unlock(&chan_list_lock);
1762 return c;
1763 }
1764
1765 /* Closest match */
1766 src_any = !bacmp(&c->src, BDADDR_ANY);
1767 dst_any = !bacmp(&c->dst, BDADDR_ANY);
1768 if ((src_match && dst_any) || (src_any && dst_match) ||
1769 (src_any && dst_any))
1770 c1 = c;
1771 }
1772 }
1773
1774 read_unlock(&chan_list_lock);
1775
1776 return c1;
1777}
1778
1779static void l2cap_monitor_timeout(struct work_struct *work)
1780{
1781 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
1782 monitor_timer.work);
1783
1784 BT_DBG("chan %p", chan);
1785
1786 l2cap_chan_lock(chan);
1787
1788 if (!chan->conn) {
1789 l2cap_chan_unlock(chan);
1790 l2cap_chan_put(chan);
1791 return;
1792 }
1793
1794 l2cap_tx(chan, NULL, NULL, L2CAP_EV_MONITOR_TO);
1795
1796 l2cap_chan_unlock(chan);
1797 l2cap_chan_put(chan);
1798}
1799
1800static void l2cap_retrans_timeout(struct work_struct *work)
1801{
1802 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
1803 retrans_timer.work);
1804
1805 BT_DBG("chan %p", chan);
1806
1807 l2cap_chan_lock(chan);
1808
1809 if (!chan->conn) {
1810 l2cap_chan_unlock(chan);
1811 l2cap_chan_put(chan);
1812 return;
1813 }
1814
1815 l2cap_tx(chan, NULL, NULL, L2CAP_EV_RETRANS_TO);
1816 l2cap_chan_unlock(chan);
1817 l2cap_chan_put(chan);
1818}
1819
1820static void l2cap_streaming_send(struct l2cap_chan *chan,
1821 struct sk_buff_head *skbs)
1822{
1823 struct sk_buff *skb;
1824 struct l2cap_ctrl *control;
1825
1826 BT_DBG("chan %p, skbs %p", chan, skbs);
1827
1828 if (__chan_is_moving(chan))
1829 return;
1830
1831 skb_queue_splice_tail_init(skbs, &chan->tx_q);
1832
1833 while (!skb_queue_empty(&chan->tx_q)) {
1834
1835 skb = skb_dequeue(&chan->tx_q);
1836
1837 bt_cb(skb)->control.retries = 1;
1838 control = &bt_cb(skb)->control;
1839
1840 control->reqseq = 0;
1841 control->txseq = chan->next_tx_seq;
1842
1843 __pack_control(chan, control, skb);
1844
1845 if (chan->fcs == L2CAP_FCS_CRC16) {
1846 u16 fcs = crc16(0, (u8 *) skb->data, skb->len);
1847 put_unaligned_le16(fcs, skb_put(skb, L2CAP_FCS_SIZE));
1848 }
1849
1850 l2cap_do_send(chan, skb);
1851
1852 BT_DBG("Sent txseq %u", control->txseq);
1853
1854 chan->next_tx_seq = __next_seq(chan, chan->next_tx_seq);
1855 chan->frames_sent++;
1856 }
1857}
1858
1859static int l2cap_ertm_send(struct l2cap_chan *chan)
1860{
1861 struct sk_buff *skb, *tx_skb;
1862 struct l2cap_ctrl *control;
1863 int sent = 0;
1864
1865 BT_DBG("chan %p", chan);
1866
1867 if (chan->state != BT_CONNECTED)
1868 return -ENOTCONN;
1869
1870 if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state))
1871 return 0;
1872
1873 if (__chan_is_moving(chan))
1874 return 0;
1875
1876 while (chan->tx_send_head &&
1877 chan->unacked_frames < chan->remote_tx_win &&
1878 chan->tx_state == L2CAP_TX_STATE_XMIT) {
1879
1880 skb = chan->tx_send_head;
1881
1882 bt_cb(skb)->control.retries = 1;
1883 control = &bt_cb(skb)->control;
1884
1885 if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state))
1886 control->final = 1;
1887
1888 control->reqseq = chan->buffer_seq;
1889 chan->last_acked_seq = chan->buffer_seq;
1890 control->txseq = chan->next_tx_seq;
1891
1892 __pack_control(chan, control, skb);
1893
1894 if (chan->fcs == L2CAP_FCS_CRC16) {
1895 u16 fcs = crc16(0, (u8 *) skb->data, skb->len);
1896 put_unaligned_le16(fcs, skb_put(skb, L2CAP_FCS_SIZE));
1897 }
1898
1899 /* Clone after data has been modified. Data is assumed to be
1900 read-only (for locking purposes) on cloned sk_buffs.
1901 */
1902 tx_skb = skb_clone(skb, GFP_KERNEL);
1903
1904 if (!tx_skb)
1905 break;
1906
1907 __set_retrans_timer(chan);
1908
1909 chan->next_tx_seq = __next_seq(chan, chan->next_tx_seq);
1910 chan->unacked_frames++;
1911 chan->frames_sent++;
1912 sent++;
1913
1914 if (skb_queue_is_last(&chan->tx_q, skb))
1915 chan->tx_send_head = NULL;
1916 else
1917 chan->tx_send_head = skb_queue_next(&chan->tx_q, skb);
1918
1919 l2cap_do_send(chan, tx_skb);
1920 BT_DBG("Sent txseq %u", control->txseq);
1921 }
1922
1923 BT_DBG("Sent %d, %u unacked, %u in ERTM queue", sent,
1924 chan->unacked_frames, skb_queue_len(&chan->tx_q));
1925
1926 return sent;
1927}
1928
1929static void l2cap_ertm_resend(struct l2cap_chan *chan)
1930{
1931 struct l2cap_ctrl control;
1932 struct sk_buff *skb;
1933 struct sk_buff *tx_skb;
1934 u16 seq;
1935
1936 BT_DBG("chan %p", chan);
1937
1938 if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state))
1939 return;
1940
1941 if (__chan_is_moving(chan))
1942 return;
1943
1944 while (chan->retrans_list.head != L2CAP_SEQ_LIST_CLEAR) {
1945 seq = l2cap_seq_list_pop(&chan->retrans_list);
1946
1947 skb = l2cap_ertm_seq_in_queue(&chan->tx_q, seq);
1948 if (!skb) {
1949 BT_DBG("Error: Can't retransmit seq %d, frame missing",
1950 seq);
1951 continue;
1952 }
1953
1954 bt_cb(skb)->control.retries++;
1955 control = bt_cb(skb)->control;
1956
1957 if (chan->max_tx != 0 &&
1958 bt_cb(skb)->control.retries > chan->max_tx) {
1959 BT_DBG("Retry limit exceeded (%d)", chan->max_tx);
1960 l2cap_send_disconn_req(chan, ECONNRESET);
1961 l2cap_seq_list_clear(&chan->retrans_list);
1962 break;
1963 }
1964
1965 control.reqseq = chan->buffer_seq;
1966 if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state))
1967 control.final = 1;
1968 else
1969 control.final = 0;
1970
1971 if (skb_cloned(skb)) {
1972 /* Cloned sk_buffs are read-only, so we need a
1973 * writeable copy
1974 */
1975 tx_skb = skb_copy(skb, GFP_KERNEL);
1976 } else {
1977 tx_skb = skb_clone(skb, GFP_KERNEL);
1978 }
1979
1980 if (!tx_skb) {
1981 l2cap_seq_list_clear(&chan->retrans_list);
1982 break;
1983 }
1984
1985 /* Update skb contents */
1986 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) {
1987 put_unaligned_le32(__pack_extended_control(&control),
1988 tx_skb->data + L2CAP_HDR_SIZE);
1989 } else {
1990 put_unaligned_le16(__pack_enhanced_control(&control),
1991 tx_skb->data + L2CAP_HDR_SIZE);
1992 }
1993
1994 if (chan->fcs == L2CAP_FCS_CRC16) {
1995 u16 fcs = crc16(0, (u8 *) tx_skb->data, tx_skb->len);
1996 put_unaligned_le16(fcs, skb_put(tx_skb,
1997 L2CAP_FCS_SIZE));
1998 }
1999
2000 l2cap_do_send(chan, tx_skb);
2001
2002 BT_DBG("Resent txseq %d", control.txseq);
2003
2004 chan->last_acked_seq = chan->buffer_seq;
2005 }
2006}
2007
2008static void l2cap_retransmit(struct l2cap_chan *chan,
2009 struct l2cap_ctrl *control)
2010{
2011 BT_DBG("chan %p, control %p", chan, control);
2012
2013 l2cap_seq_list_append(&chan->retrans_list, control->reqseq);
2014 l2cap_ertm_resend(chan);
2015}
2016
2017static void l2cap_retransmit_all(struct l2cap_chan *chan,
2018 struct l2cap_ctrl *control)
2019{
2020 struct sk_buff *skb;
2021
2022 BT_DBG("chan %p, control %p", chan, control);
2023
2024 if (control->poll)
2025 set_bit(CONN_SEND_FBIT, &chan->conn_state);
2026
2027 l2cap_seq_list_clear(&chan->retrans_list);
2028
2029 if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state))
2030 return;
2031
2032 if (chan->unacked_frames) {
2033 skb_queue_walk(&chan->tx_q, skb) {
2034 if (bt_cb(skb)->control.txseq == control->reqseq ||
2035 skb == chan->tx_send_head)
2036 break;
2037 }
2038
2039 skb_queue_walk_from(&chan->tx_q, skb) {
2040 if (skb == chan->tx_send_head)
2041 break;
2042
2043 l2cap_seq_list_append(&chan->retrans_list,
2044 bt_cb(skb)->control.txseq);
2045 }
2046
2047 l2cap_ertm_resend(chan);
2048 }
2049}
2050
2051static void l2cap_send_ack(struct l2cap_chan *chan)
2052{
2053 struct l2cap_ctrl control;
2054 u16 frames_to_ack = __seq_offset(chan, chan->buffer_seq,
2055 chan->last_acked_seq);
2056 int threshold;
2057
2058 BT_DBG("chan %p last_acked_seq %d buffer_seq %d",
2059 chan, chan->last_acked_seq, chan->buffer_seq);
2060
2061 memset(&control, 0, sizeof(control));
2062 control.sframe = 1;
2063
2064 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state) &&
2065 chan->rx_state == L2CAP_RX_STATE_RECV) {
2066 __clear_ack_timer(chan);
2067 control.super = L2CAP_SUPER_RNR;
2068 control.reqseq = chan->buffer_seq;
2069 l2cap_send_sframe(chan, &control);
2070 } else {
2071 if (!test_bit(CONN_REMOTE_BUSY, &chan->conn_state)) {
2072 l2cap_ertm_send(chan);
2073 /* If any i-frames were sent, they included an ack */
2074 if (chan->buffer_seq == chan->last_acked_seq)
2075 frames_to_ack = 0;
2076 }
2077
2078 /* Ack now if the window is 3/4ths full.
2079 * Calculate without mul or div
2080 */
2081 threshold = chan->ack_win;
2082 threshold += threshold << 1;
2083 threshold >>= 2;
2084
2085 BT_DBG("frames_to_ack %u, threshold %d", frames_to_ack,
2086 threshold);
2087
2088 if (frames_to_ack >= threshold) {
2089 __clear_ack_timer(chan);
2090 control.super = L2CAP_SUPER_RR;
2091 control.reqseq = chan->buffer_seq;
2092 l2cap_send_sframe(chan, &control);
2093 frames_to_ack = 0;
2094 }
2095
2096 if (frames_to_ack)
2097 __set_ack_timer(chan);
2098 }
2099}
2100
2101static inline int l2cap_skbuff_fromiovec(struct l2cap_chan *chan,
2102 struct msghdr *msg, int len,
2103 int count, struct sk_buff *skb)
2104{
2105 struct l2cap_conn *conn = chan->conn;
2106 struct sk_buff **frag;
2107 int sent = 0;
2108
2109 if (memcpy_fromiovec(skb_put(skb, count), msg->msg_iov, count))
2110 return -EFAULT;
2111
2112 sent += count;
2113 len -= count;
2114
2115 /* Continuation fragments (no L2CAP header) */
2116 frag = &skb_shinfo(skb)->frag_list;
2117 while (len) {
2118 struct sk_buff *tmp;
2119
2120 count = min_t(unsigned int, conn->mtu, len);
2121
2122 tmp = chan->ops->alloc_skb(chan, count,
2123 msg->msg_flags & MSG_DONTWAIT);
2124 if (IS_ERR(tmp))
2125 return PTR_ERR(tmp);
2126
2127 *frag = tmp;
2128
2129 if (memcpy_fromiovec(skb_put(*frag, count), msg->msg_iov, count))
2130 return -EFAULT;
2131
2132 (*frag)->priority = skb->priority;
2133
2134 sent += count;
2135 len -= count;
2136
2137 skb->len += (*frag)->len;
2138 skb->data_len += (*frag)->len;
2139
2140 frag = &(*frag)->next;
2141 }
2142
2143 return sent;
2144}
2145
2146static struct sk_buff *l2cap_create_connless_pdu(struct l2cap_chan *chan,
2147 struct msghdr *msg, size_t len,
2148 u32 priority)
2149{
2150 struct l2cap_conn *conn = chan->conn;
2151 struct sk_buff *skb;
2152 int err, count, hlen = L2CAP_HDR_SIZE + L2CAP_PSMLEN_SIZE;
2153 struct l2cap_hdr *lh;
2154
2155 BT_DBG("chan %p psm 0x%2.2x len %zu priority %u", chan,
2156 __le16_to_cpu(chan->psm), len, priority);
2157
2158 count = min_t(unsigned int, (conn->mtu - hlen), len);
2159
2160 skb = chan->ops->alloc_skb(chan, count + hlen,
2161 msg->msg_flags & MSG_DONTWAIT);
2162 if (IS_ERR(skb))
2163 return skb;
2164
2165 skb->priority = priority;
2166
2167 /* Create L2CAP header */
2168 lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
2169 lh->cid = cpu_to_le16(chan->dcid);
2170 lh->len = cpu_to_le16(len + L2CAP_PSMLEN_SIZE);
2171 put_unaligned(chan->psm, (__le16 *) skb_put(skb, L2CAP_PSMLEN_SIZE));
2172
2173 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2174 if (unlikely(err < 0)) {
2175 kfree_skb(skb);
2176 return ERR_PTR(err);
2177 }
2178 return skb;
2179}
2180
2181static struct sk_buff *l2cap_create_basic_pdu(struct l2cap_chan *chan,
2182 struct msghdr *msg, size_t len,
2183 u32 priority)
2184{
2185 struct l2cap_conn *conn = chan->conn;
2186 struct sk_buff *skb;
2187 int err, count;
2188 struct l2cap_hdr *lh;
2189
2190 BT_DBG("chan %p len %zu", chan, len);
2191
2192 count = min_t(unsigned int, (conn->mtu - L2CAP_HDR_SIZE), len);
2193
2194 skb = chan->ops->alloc_skb(chan, count + L2CAP_HDR_SIZE,
2195 msg->msg_flags & MSG_DONTWAIT);
2196 if (IS_ERR(skb))
2197 return skb;
2198
2199 skb->priority = priority;
2200
2201 /* Create L2CAP header */
2202 lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
2203 lh->cid = cpu_to_le16(chan->dcid);
2204 lh->len = cpu_to_le16(len);
2205
2206 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2207 if (unlikely(err < 0)) {
2208 kfree_skb(skb);
2209 return ERR_PTR(err);
2210 }
2211 return skb;
2212}
2213
2214static struct sk_buff *l2cap_create_iframe_pdu(struct l2cap_chan *chan,
2215 struct msghdr *msg, size_t len,
2216 u16 sdulen)
2217{
2218 struct l2cap_conn *conn = chan->conn;
2219 struct sk_buff *skb;
2220 int err, count, hlen;
2221 struct l2cap_hdr *lh;
2222
2223 BT_DBG("chan %p len %zu", chan, len);
2224
2225 if (!conn)
2226 return ERR_PTR(-ENOTCONN);
2227
2228 hlen = __ertm_hdr_size(chan);
2229
2230 if (sdulen)
2231 hlen += L2CAP_SDULEN_SIZE;
2232
2233 if (chan->fcs == L2CAP_FCS_CRC16)
2234 hlen += L2CAP_FCS_SIZE;
2235
2236 count = min_t(unsigned int, (conn->mtu - hlen), len);
2237
2238 skb = chan->ops->alloc_skb(chan, count + hlen,
2239 msg->msg_flags & MSG_DONTWAIT);
2240 if (IS_ERR(skb))
2241 return skb;
2242
2243 /* Create L2CAP header */
2244 lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
2245 lh->cid = cpu_to_le16(chan->dcid);
2246 lh->len = cpu_to_le16(len + (hlen - L2CAP_HDR_SIZE));
2247
2248 /* Control header is populated later */
2249 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
2250 put_unaligned_le32(0, skb_put(skb, L2CAP_EXT_CTRL_SIZE));
2251 else
2252 put_unaligned_le16(0, skb_put(skb, L2CAP_ENH_CTRL_SIZE));
2253
2254 if (sdulen)
2255 put_unaligned_le16(sdulen, skb_put(skb, L2CAP_SDULEN_SIZE));
2256
2257 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2258 if (unlikely(err < 0)) {
2259 kfree_skb(skb);
2260 return ERR_PTR(err);
2261 }
2262
2263 bt_cb(skb)->control.fcs = chan->fcs;
2264 bt_cb(skb)->control.retries = 0;
2265 return skb;
2266}
2267
2268static int l2cap_segment_sdu(struct l2cap_chan *chan,
2269 struct sk_buff_head *seg_queue,
2270 struct msghdr *msg, size_t len)
2271{
2272 struct sk_buff *skb;
2273 u16 sdu_len;
2274 size_t pdu_len;
2275 u8 sar;
2276
2277 BT_DBG("chan %p, msg %p, len %zu", chan, msg, len);
2278
2279 /* It is critical that ERTM PDUs fit in a single HCI fragment,
2280 * so fragmented skbs are not used. The HCI layer's handling
2281 * of fragmented skbs is not compatible with ERTM's queueing.
2282 */
2283
2284 /* PDU size is derived from the HCI MTU */
2285 pdu_len = chan->conn->mtu;
2286
2287 /* Constrain PDU size for BR/EDR connections */
2288 if (!chan->hs_hcon)
2289 pdu_len = min_t(size_t, pdu_len, L2CAP_BREDR_MAX_PAYLOAD);
2290
2291 /* Adjust for largest possible L2CAP overhead. */
2292 if (chan->fcs)
2293 pdu_len -= L2CAP_FCS_SIZE;
2294
2295 pdu_len -= __ertm_hdr_size(chan);
2296
2297 /* Remote device may have requested smaller PDUs */
2298 pdu_len = min_t(size_t, pdu_len, chan->remote_mps);
2299
2300 if (len <= pdu_len) {
2301 sar = L2CAP_SAR_UNSEGMENTED;
2302 sdu_len = 0;
2303 pdu_len = len;
2304 } else {
2305 sar = L2CAP_SAR_START;
2306 sdu_len = len;
2307 pdu_len -= L2CAP_SDULEN_SIZE;
2308 }
2309
2310 while (len > 0) {
2311 skb = l2cap_create_iframe_pdu(chan, msg, pdu_len, sdu_len);
2312
2313 if (IS_ERR(skb)) {
2314 __skb_queue_purge(seg_queue);
2315 return PTR_ERR(skb);
2316 }
2317
2318 bt_cb(skb)->control.sar = sar;
2319 __skb_queue_tail(seg_queue, skb);
2320
2321 len -= pdu_len;
2322 if (sdu_len) {
2323 sdu_len = 0;
2324 pdu_len += L2CAP_SDULEN_SIZE;
2325 }
2326
2327 if (len <= pdu_len) {
2328 sar = L2CAP_SAR_END;
2329 pdu_len = len;
2330 } else {
2331 sar = L2CAP_SAR_CONTINUE;
2332 }
2333 }
2334
2335 return 0;
2336}
2337
2338static struct sk_buff *l2cap_create_le_flowctl_pdu(struct l2cap_chan *chan,
2339 struct msghdr *msg,
2340 size_t len, u16 sdulen)
2341{
2342 struct l2cap_conn *conn = chan->conn;
2343 struct sk_buff *skb;
2344 int err, count, hlen;
2345 struct l2cap_hdr *lh;
2346
2347 BT_DBG("chan %p len %zu", chan, len);
2348
2349 if (!conn)
2350 return ERR_PTR(-ENOTCONN);
2351
2352 hlen = L2CAP_HDR_SIZE;
2353
2354 if (sdulen)
2355 hlen += L2CAP_SDULEN_SIZE;
2356
2357 count = min_t(unsigned int, (conn->mtu - hlen), len);
2358
2359 skb = chan->ops->alloc_skb(chan, count + hlen,
2360 msg->msg_flags & MSG_DONTWAIT);
2361 if (IS_ERR(skb))
2362 return skb;
2363
2364 /* Create L2CAP header */
2365 lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
2366 lh->cid = cpu_to_le16(chan->dcid);
2367 lh->len = cpu_to_le16(len + (hlen - L2CAP_HDR_SIZE));
2368
2369 if (sdulen)
2370 put_unaligned_le16(sdulen, skb_put(skb, L2CAP_SDULEN_SIZE));
2371
2372 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2373 if (unlikely(err < 0)) {
2374 kfree_skb(skb);
2375 return ERR_PTR(err);
2376 }
2377
2378 return skb;
2379}
2380
2381static int l2cap_segment_le_sdu(struct l2cap_chan *chan,
2382 struct sk_buff_head *seg_queue,
2383 struct msghdr *msg, size_t len)
2384{
2385 struct sk_buff *skb;
2386 size_t pdu_len;
2387 u16 sdu_len;
2388
2389 BT_DBG("chan %p, msg %p, len %zu", chan, msg, len);
2390
2391 pdu_len = chan->conn->mtu - L2CAP_HDR_SIZE;
2392
2393 pdu_len = min_t(size_t, pdu_len, chan->remote_mps);
2394
2395 sdu_len = len;
2396 pdu_len -= L2CAP_SDULEN_SIZE;
2397
2398 while (len > 0) {
2399 if (len <= pdu_len)
2400 pdu_len = len;
2401
2402 skb = l2cap_create_le_flowctl_pdu(chan, msg, pdu_len, sdu_len);
2403 if (IS_ERR(skb)) {
2404 __skb_queue_purge(seg_queue);
2405 return PTR_ERR(skb);
2406 }
2407
2408 __skb_queue_tail(seg_queue, skb);
2409
2410 len -= pdu_len;
2411
2412 if (sdu_len) {
2413 sdu_len = 0;
2414 pdu_len += L2CAP_SDULEN_SIZE;
2415 }
2416 }
2417
2418 return 0;
2419}
2420
2421int l2cap_chan_send(struct l2cap_chan *chan, struct msghdr *msg, size_t len,
2422 u32 priority)
2423{
2424 struct sk_buff *skb;
2425 int err;
2426 struct sk_buff_head seg_queue;
2427
2428 if (!chan->conn)
2429 return -ENOTCONN;
2430
2431 /* Connectionless channel */
2432 if (chan->chan_type == L2CAP_CHAN_CONN_LESS) {
2433 skb = l2cap_create_connless_pdu(chan, msg, len, priority);
2434 if (IS_ERR(skb))
2435 return PTR_ERR(skb);
2436
2437 /* Channel lock is released before requesting new skb and then
2438 * reacquired thus we need to recheck channel state.
2439 */
2440 if (chan->state != BT_CONNECTED) {
2441 kfree_skb(skb);
2442 return -ENOTCONN;
2443 }
2444
2445 l2cap_do_send(chan, skb);
2446 return len;
2447 }
2448
2449 switch (chan->mode) {
2450 case L2CAP_MODE_LE_FLOWCTL:
2451 /* Check outgoing MTU */
2452 if (len > chan->omtu)
2453 return -EMSGSIZE;
2454
2455 if (!chan->tx_credits)
2456 return -EAGAIN;
2457
2458 __skb_queue_head_init(&seg_queue);
2459
2460 err = l2cap_segment_le_sdu(chan, &seg_queue, msg, len);
2461
2462 if (chan->state != BT_CONNECTED) {
2463 __skb_queue_purge(&seg_queue);
2464 err = -ENOTCONN;
2465 }
2466
2467 if (err)
2468 return err;
2469
2470 skb_queue_splice_tail_init(&seg_queue, &chan->tx_q);
2471
2472 while (chan->tx_credits && !skb_queue_empty(&chan->tx_q)) {
2473 l2cap_do_send(chan, skb_dequeue(&chan->tx_q));
2474 chan->tx_credits--;
2475 }
2476
2477 if (!chan->tx_credits)
2478 chan->ops->suspend(chan);
2479
2480 err = len;
2481
2482 break;
2483
2484 case L2CAP_MODE_BASIC:
2485 /* Check outgoing MTU */
2486 if (len > chan->omtu)
2487 return -EMSGSIZE;
2488
2489 /* Create a basic PDU */
2490 skb = l2cap_create_basic_pdu(chan, msg, len, priority);
2491 if (IS_ERR(skb))
2492 return PTR_ERR(skb);
2493
2494 /* Channel lock is released before requesting new skb and then
2495 * reacquired thus we need to recheck channel state.
2496 */
2497 if (chan->state != BT_CONNECTED) {
2498 kfree_skb(skb);
2499 return -ENOTCONN;
2500 }
2501
2502 l2cap_do_send(chan, skb);
2503 err = len;
2504 break;
2505
2506 case L2CAP_MODE_ERTM:
2507 case L2CAP_MODE_STREAMING:
2508 /* Check outgoing MTU */
2509 if (len > chan->omtu) {
2510 err = -EMSGSIZE;
2511 break;
2512 }
2513
2514 __skb_queue_head_init(&seg_queue);
2515
2516 /* Do segmentation before calling in to the state machine,
2517 * since it's possible to block while waiting for memory
2518 * allocation.
2519 */
2520 err = l2cap_segment_sdu(chan, &seg_queue, msg, len);
2521
2522 /* The channel could have been closed while segmenting,
2523 * check that it is still connected.
2524 */
2525 if (chan->state != BT_CONNECTED) {
2526 __skb_queue_purge(&seg_queue);
2527 err = -ENOTCONN;
2528 }
2529
2530 if (err)
2531 break;
2532
2533 if (chan->mode == L2CAP_MODE_ERTM)
2534 l2cap_tx(chan, NULL, &seg_queue, L2CAP_EV_DATA_REQUEST);
2535 else
2536 l2cap_streaming_send(chan, &seg_queue);
2537
2538 err = len;
2539
2540 /* If the skbs were not queued for sending, they'll still be in
2541 * seg_queue and need to be purged.
2542 */
2543 __skb_queue_purge(&seg_queue);
2544 break;
2545
2546 default:
2547 BT_DBG("bad state %1.1x", chan->mode);
2548 err = -EBADFD;
2549 }
2550
2551 return err;
2552}
2553
2554static void l2cap_send_srej(struct l2cap_chan *chan, u16 txseq)
2555{
2556 struct l2cap_ctrl control;
2557 u16 seq;
2558
2559 BT_DBG("chan %p, txseq %u", chan, txseq);
2560
2561 memset(&control, 0, sizeof(control));
2562 control.sframe = 1;
2563 control.super = L2CAP_SUPER_SREJ;
2564
2565 for (seq = chan->expected_tx_seq; seq != txseq;
2566 seq = __next_seq(chan, seq)) {
2567 if (!l2cap_ertm_seq_in_queue(&chan->srej_q, seq)) {
2568 control.reqseq = seq;
2569 l2cap_send_sframe(chan, &control);
2570 l2cap_seq_list_append(&chan->srej_list, seq);
2571 }
2572 }
2573
2574 chan->expected_tx_seq = __next_seq(chan, txseq);
2575}
2576
2577static void l2cap_send_srej_tail(struct l2cap_chan *chan)
2578{
2579 struct l2cap_ctrl control;
2580
2581 BT_DBG("chan %p", chan);
2582
2583 if (chan->srej_list.tail == L2CAP_SEQ_LIST_CLEAR)
2584 return;
2585
2586 memset(&control, 0, sizeof(control));
2587 control.sframe = 1;
2588 control.super = L2CAP_SUPER_SREJ;
2589 control.reqseq = chan->srej_list.tail;
2590 l2cap_send_sframe(chan, &control);
2591}
2592
2593static void l2cap_send_srej_list(struct l2cap_chan *chan, u16 txseq)
2594{
2595 struct l2cap_ctrl control;
2596 u16 initial_head;
2597 u16 seq;
2598
2599 BT_DBG("chan %p, txseq %u", chan, txseq);
2600
2601 memset(&control, 0, sizeof(control));
2602 control.sframe = 1;
2603 control.super = L2CAP_SUPER_SREJ;
2604
2605 /* Capture initial list head to allow only one pass through the list. */
2606 initial_head = chan->srej_list.head;
2607
2608 do {
2609 seq = l2cap_seq_list_pop(&chan->srej_list);
2610 if (seq == txseq || seq == L2CAP_SEQ_LIST_CLEAR)
2611 break;
2612
2613 control.reqseq = seq;
2614 l2cap_send_sframe(chan, &control);
2615 l2cap_seq_list_append(&chan->srej_list, seq);
2616 } while (chan->srej_list.head != initial_head);
2617}
2618
2619static void l2cap_process_reqseq(struct l2cap_chan *chan, u16 reqseq)
2620{
2621 struct sk_buff *acked_skb;
2622 u16 ackseq;
2623
2624 BT_DBG("chan %p, reqseq %u", chan, reqseq);
2625
2626 if (chan->unacked_frames == 0 || reqseq == chan->expected_ack_seq)
2627 return;
2628
2629 BT_DBG("expected_ack_seq %u, unacked_frames %u",
2630 chan->expected_ack_seq, chan->unacked_frames);
2631
2632 for (ackseq = chan->expected_ack_seq; ackseq != reqseq;
2633 ackseq = __next_seq(chan, ackseq)) {
2634
2635 acked_skb = l2cap_ertm_seq_in_queue(&chan->tx_q, ackseq);
2636 if (acked_skb) {
2637 skb_unlink(acked_skb, &chan->tx_q);
2638 kfree_skb(acked_skb);
2639 chan->unacked_frames--;
2640 }
2641 }
2642
2643 chan->expected_ack_seq = reqseq;
2644
2645 if (chan->unacked_frames == 0)
2646 __clear_retrans_timer(chan);
2647
2648 BT_DBG("unacked_frames %u", chan->unacked_frames);
2649}
2650
2651static void l2cap_abort_rx_srej_sent(struct l2cap_chan *chan)
2652{
2653 BT_DBG("chan %p", chan);
2654
2655 chan->expected_tx_seq = chan->buffer_seq;
2656 l2cap_seq_list_clear(&chan->srej_list);
2657 skb_queue_purge(&chan->srej_q);
2658 chan->rx_state = L2CAP_RX_STATE_RECV;
2659}
2660
2661static void l2cap_tx_state_xmit(struct l2cap_chan *chan,
2662 struct l2cap_ctrl *control,
2663 struct sk_buff_head *skbs, u8 event)
2664{
2665 BT_DBG("chan %p, control %p, skbs %p, event %d", chan, control, skbs,
2666 event);
2667
2668 switch (event) {
2669 case L2CAP_EV_DATA_REQUEST:
2670 if (chan->tx_send_head == NULL)
2671 chan->tx_send_head = skb_peek(skbs);
2672
2673 skb_queue_splice_tail_init(skbs, &chan->tx_q);
2674 l2cap_ertm_send(chan);
2675 break;
2676 case L2CAP_EV_LOCAL_BUSY_DETECTED:
2677 BT_DBG("Enter LOCAL_BUSY");
2678 set_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2679
2680 if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) {
2681 /* The SREJ_SENT state must be aborted if we are to
2682 * enter the LOCAL_BUSY state.
2683 */
2684 l2cap_abort_rx_srej_sent(chan);
2685 }
2686
2687 l2cap_send_ack(chan);
2688
2689 break;
2690 case L2CAP_EV_LOCAL_BUSY_CLEAR:
2691 BT_DBG("Exit LOCAL_BUSY");
2692 clear_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2693
2694 if (test_bit(CONN_RNR_SENT, &chan->conn_state)) {
2695 struct l2cap_ctrl local_control;
2696
2697 memset(&local_control, 0, sizeof(local_control));
2698 local_control.sframe = 1;
2699 local_control.super = L2CAP_SUPER_RR;
2700 local_control.poll = 1;
2701 local_control.reqseq = chan->buffer_seq;
2702 l2cap_send_sframe(chan, &local_control);
2703
2704 chan->retry_count = 1;
2705 __set_monitor_timer(chan);
2706 chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2707 }
2708 break;
2709 case L2CAP_EV_RECV_REQSEQ_AND_FBIT:
2710 l2cap_process_reqseq(chan, control->reqseq);
2711 break;
2712 case L2CAP_EV_EXPLICIT_POLL:
2713 l2cap_send_rr_or_rnr(chan, 1);
2714 chan->retry_count = 1;
2715 __set_monitor_timer(chan);
2716 __clear_ack_timer(chan);
2717 chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2718 break;
2719 case L2CAP_EV_RETRANS_TO:
2720 l2cap_send_rr_or_rnr(chan, 1);
2721 chan->retry_count = 1;
2722 __set_monitor_timer(chan);
2723 chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2724 break;
2725 case L2CAP_EV_RECV_FBIT:
2726 /* Nothing to process */
2727 break;
2728 default:
2729 break;
2730 }
2731}
2732
2733static void l2cap_tx_state_wait_f(struct l2cap_chan *chan,
2734 struct l2cap_ctrl *control,
2735 struct sk_buff_head *skbs, u8 event)
2736{
2737 BT_DBG("chan %p, control %p, skbs %p, event %d", chan, control, skbs,
2738 event);
2739
2740 switch (event) {
2741 case L2CAP_EV_DATA_REQUEST:
2742 if (chan->tx_send_head == NULL)
2743 chan->tx_send_head = skb_peek(skbs);
2744 /* Queue data, but don't send. */
2745 skb_queue_splice_tail_init(skbs, &chan->tx_q);
2746 break;
2747 case L2CAP_EV_LOCAL_BUSY_DETECTED:
2748 BT_DBG("Enter LOCAL_BUSY");
2749 set_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2750
2751 if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) {
2752 /* The SREJ_SENT state must be aborted if we are to
2753 * enter the LOCAL_BUSY state.
2754 */
2755 l2cap_abort_rx_srej_sent(chan);
2756 }
2757
2758 l2cap_send_ack(chan);
2759
2760 break;
2761 case L2CAP_EV_LOCAL_BUSY_CLEAR:
2762 BT_DBG("Exit LOCAL_BUSY");
2763 clear_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2764
2765 if (test_bit(CONN_RNR_SENT, &chan->conn_state)) {
2766 struct l2cap_ctrl local_control;
2767 memset(&local_control, 0, sizeof(local_control));
2768 local_control.sframe = 1;
2769 local_control.super = L2CAP_SUPER_RR;
2770 local_control.poll = 1;
2771 local_control.reqseq = chan->buffer_seq;
2772 l2cap_send_sframe(chan, &local_control);
2773
2774 chan->retry_count = 1;
2775 __set_monitor_timer(chan);
2776 chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2777 }
2778 break;
2779 case L2CAP_EV_RECV_REQSEQ_AND_FBIT:
2780 l2cap_process_reqseq(chan, control->reqseq);
2781
2782 /* Fall through */
2783
2784 case L2CAP_EV_RECV_FBIT:
2785 if (control && control->final) {
2786 __clear_monitor_timer(chan);
2787 if (chan->unacked_frames > 0)
2788 __set_retrans_timer(chan);
2789 chan->retry_count = 0;
2790 chan->tx_state = L2CAP_TX_STATE_XMIT;
2791 BT_DBG("recv fbit tx_state 0x2.2%x", chan->tx_state);
2792 }
2793 break;
2794 case L2CAP_EV_EXPLICIT_POLL:
2795 /* Ignore */
2796 break;
2797 case L2CAP_EV_MONITOR_TO:
2798 if (chan->max_tx == 0 || chan->retry_count < chan->max_tx) {
2799 l2cap_send_rr_or_rnr(chan, 1);
2800 __set_monitor_timer(chan);
2801 chan->retry_count++;
2802 } else {
2803 l2cap_send_disconn_req(chan, ECONNABORTED);
2804 }
2805 break;
2806 default:
2807 break;
2808 }
2809}
2810
2811static void l2cap_tx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
2812 struct sk_buff_head *skbs, u8 event)
2813{
2814 BT_DBG("chan %p, control %p, skbs %p, event %d, state %d",
2815 chan, control, skbs, event, chan->tx_state);
2816
2817 switch (chan->tx_state) {
2818 case L2CAP_TX_STATE_XMIT:
2819 l2cap_tx_state_xmit(chan, control, skbs, event);
2820 break;
2821 case L2CAP_TX_STATE_WAIT_F:
2822 l2cap_tx_state_wait_f(chan, control, skbs, event);
2823 break;
2824 default:
2825 /* Ignore event */
2826 break;
2827 }
2828}
2829
2830static void l2cap_pass_to_tx(struct l2cap_chan *chan,
2831 struct l2cap_ctrl *control)
2832{
2833 BT_DBG("chan %p, control %p", chan, control);
2834 l2cap_tx(chan, control, NULL, L2CAP_EV_RECV_REQSEQ_AND_FBIT);
2835}
2836
2837static void l2cap_pass_to_tx_fbit(struct l2cap_chan *chan,
2838 struct l2cap_ctrl *control)
2839{
2840 BT_DBG("chan %p, control %p", chan, control);
2841 l2cap_tx(chan, control, NULL, L2CAP_EV_RECV_FBIT);
2842}
2843
2844/* Copy frame to all raw sockets on that connection */
2845static void l2cap_raw_recv(struct l2cap_conn *conn, struct sk_buff *skb)
2846{
2847 struct sk_buff *nskb;
2848 struct l2cap_chan *chan;
2849
2850 BT_DBG("conn %p", conn);
2851
2852 mutex_lock(&conn->chan_lock);
2853
2854 list_for_each_entry(chan, &conn->chan_l, list) {
2855 if (chan->chan_type != L2CAP_CHAN_RAW)
2856 continue;
2857
2858 /* Don't send frame to the channel it came from */
2859 if (bt_cb(skb)->chan == chan)
2860 continue;
2861
2862 nskb = skb_clone(skb, GFP_KERNEL);
2863 if (!nskb)
2864 continue;
2865 if (chan->ops->recv(chan, nskb))
2866 kfree_skb(nskb);
2867 }
2868
2869 mutex_unlock(&conn->chan_lock);
2870}
2871
2872/* ---- L2CAP signalling commands ---- */
2873static struct sk_buff *l2cap_build_cmd(struct l2cap_conn *conn, u8 code,
2874 u8 ident, u16 dlen, void *data)
2875{
2876 struct sk_buff *skb, **frag;
2877 struct l2cap_cmd_hdr *cmd;
2878 struct l2cap_hdr *lh;
2879 int len, count;
2880
2881 BT_DBG("conn %p, code 0x%2.2x, ident 0x%2.2x, len %u",
2882 conn, code, ident, dlen);
2883
2884 if (conn->mtu < L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE)
2885 return NULL;
2886
2887 len = L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE + dlen;
2888 count = min_t(unsigned int, conn->mtu, len);
2889
2890 skb = bt_skb_alloc(count, GFP_KERNEL);
2891 if (!skb)
2892 return NULL;
2893
2894 lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
2895 lh->len = cpu_to_le16(L2CAP_CMD_HDR_SIZE + dlen);
2896
2897 if (conn->hcon->type == LE_LINK)
2898 lh->cid = cpu_to_le16(L2CAP_CID_LE_SIGNALING);
2899 else
2900 lh->cid = cpu_to_le16(L2CAP_CID_SIGNALING);
2901
2902 cmd = (struct l2cap_cmd_hdr *) skb_put(skb, L2CAP_CMD_HDR_SIZE);
2903 cmd->code = code;
2904 cmd->ident = ident;
2905 cmd->len = cpu_to_le16(dlen);
2906
2907 if (dlen) {
2908 count -= L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE;
2909 memcpy(skb_put(skb, count), data, count);
2910 data += count;
2911 }
2912
2913 len -= skb->len;
2914
2915 /* Continuation fragments (no L2CAP header) */
2916 frag = &skb_shinfo(skb)->frag_list;
2917 while (len) {
2918 count = min_t(unsigned int, conn->mtu, len);
2919
2920 *frag = bt_skb_alloc(count, GFP_KERNEL);
2921 if (!*frag)
2922 goto fail;
2923
2924 memcpy(skb_put(*frag, count), data, count);
2925
2926 len -= count;
2927 data += count;
2928
2929 frag = &(*frag)->next;
2930 }
2931
2932 return skb;
2933
2934fail:
2935 kfree_skb(skb);
2936 return NULL;
2937}
2938
2939static inline int l2cap_get_conf_opt(void **ptr, int *type, int *olen,
2940 unsigned long *val)
2941{
2942 struct l2cap_conf_opt *opt = *ptr;
2943 int len;
2944
2945 len = L2CAP_CONF_OPT_SIZE + opt->len;
2946 *ptr += len;
2947
2948 *type = opt->type;
2949 *olen = opt->len;
2950
2951 switch (opt->len) {
2952 case 1:
2953 *val = *((u8 *) opt->val);
2954 break;
2955
2956 case 2:
2957 *val = get_unaligned_le16(opt->val);
2958 break;
2959
2960 case 4:
2961 *val = get_unaligned_le32(opt->val);
2962 break;
2963
2964 default:
2965 *val = (unsigned long) opt->val;
2966 break;
2967 }
2968
2969 BT_DBG("type 0x%2.2x len %u val 0x%lx", *type, opt->len, *val);
2970 return len;
2971}
2972
2973static void l2cap_add_conf_opt(void **ptr, u8 type, u8 len, unsigned long val)
2974{
2975 struct l2cap_conf_opt *opt = *ptr;
2976
2977 BT_DBG("type 0x%2.2x len %u val 0x%lx", type, len, val);
2978
2979 opt->type = type;
2980 opt->len = len;
2981
2982 switch (len) {
2983 case 1:
2984 *((u8 *) opt->val) = val;
2985 break;
2986
2987 case 2:
2988 put_unaligned_le16(val, opt->val);
2989 break;
2990
2991 case 4:
2992 put_unaligned_le32(val, opt->val);
2993 break;
2994
2995 default:
2996 memcpy(opt->val, (void *) val, len);
2997 break;
2998 }
2999
3000 *ptr += L2CAP_CONF_OPT_SIZE + len;
3001}
3002
3003static void l2cap_add_opt_efs(void **ptr, struct l2cap_chan *chan)
3004{
3005 struct l2cap_conf_efs efs;
3006
3007 switch (chan->mode) {
3008 case L2CAP_MODE_ERTM:
3009 efs.id = chan->local_id;
3010 efs.stype = chan->local_stype;
3011 efs.msdu = cpu_to_le16(chan->local_msdu);
3012 efs.sdu_itime = cpu_to_le32(chan->local_sdu_itime);
3013 efs.acc_lat = cpu_to_le32(L2CAP_DEFAULT_ACC_LAT);
3014 efs.flush_to = cpu_to_le32(L2CAP_EFS_DEFAULT_FLUSH_TO);
3015 break;
3016
3017 case L2CAP_MODE_STREAMING:
3018 efs.id = 1;
3019 efs.stype = L2CAP_SERV_BESTEFFORT;
3020 efs.msdu = cpu_to_le16(chan->local_msdu);
3021 efs.sdu_itime = cpu_to_le32(chan->local_sdu_itime);
3022 efs.acc_lat = 0;
3023 efs.flush_to = 0;
3024 break;
3025
3026 default:
3027 return;
3028 }
3029
3030 l2cap_add_conf_opt(ptr, L2CAP_CONF_EFS, sizeof(efs),
3031 (unsigned long) &efs);
3032}
3033
3034static void l2cap_ack_timeout(struct work_struct *work)
3035{
3036 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
3037 ack_timer.work);
3038 u16 frames_to_ack;
3039
3040 BT_DBG("chan %p", chan);
3041
3042 l2cap_chan_lock(chan);
3043
3044 frames_to_ack = __seq_offset(chan, chan->buffer_seq,
3045 chan->last_acked_seq);
3046
3047 if (frames_to_ack)
3048 l2cap_send_rr_or_rnr(chan, 0);
3049
3050 l2cap_chan_unlock(chan);
3051 l2cap_chan_put(chan);
3052}
3053
3054int l2cap_ertm_init(struct l2cap_chan *chan)
3055{
3056 int err;
3057
3058 chan->next_tx_seq = 0;
3059 chan->expected_tx_seq = 0;
3060 chan->expected_ack_seq = 0;
3061 chan->unacked_frames = 0;
3062 chan->buffer_seq = 0;
3063 chan->frames_sent = 0;
3064 chan->last_acked_seq = 0;
3065 chan->sdu = NULL;
3066 chan->sdu_last_frag = NULL;
3067 chan->sdu_len = 0;
3068
3069 skb_queue_head_init(&chan->tx_q);
3070
3071 chan->local_amp_id = AMP_ID_BREDR;
3072 chan->move_id = AMP_ID_BREDR;
3073 chan->move_state = L2CAP_MOVE_STABLE;
3074 chan->move_role = L2CAP_MOVE_ROLE_NONE;
3075
3076 if (chan->mode != L2CAP_MODE_ERTM)
3077 return 0;
3078
3079 chan->rx_state = L2CAP_RX_STATE_RECV;
3080 chan->tx_state = L2CAP_TX_STATE_XMIT;
3081
3082 INIT_DELAYED_WORK(&chan->retrans_timer, l2cap_retrans_timeout);
3083 INIT_DELAYED_WORK(&chan->monitor_timer, l2cap_monitor_timeout);
3084 INIT_DELAYED_WORK(&chan->ack_timer, l2cap_ack_timeout);
3085
3086 skb_queue_head_init(&chan->srej_q);
3087
3088 err = l2cap_seq_list_init(&chan->srej_list, chan->tx_win);
3089 if (err < 0)
3090 return err;
3091
3092 err = l2cap_seq_list_init(&chan->retrans_list, chan->remote_tx_win);
3093 if (err < 0)
3094 l2cap_seq_list_free(&chan->srej_list);
3095
3096 return err;
3097}
3098
3099static inline __u8 l2cap_select_mode(__u8 mode, __u16 remote_feat_mask)
3100{
3101 switch (mode) {
3102 case L2CAP_MODE_STREAMING:
3103 case L2CAP_MODE_ERTM:
3104 if (l2cap_mode_supported(mode, remote_feat_mask))
3105 return mode;
3106 /* fall through */
3107 default:
3108 return L2CAP_MODE_BASIC;
3109 }
3110}
3111
3112static inline bool __l2cap_ews_supported(struct l2cap_conn *conn)
3113{
3114 return conn->hs_enabled && conn->feat_mask & L2CAP_FEAT_EXT_WINDOW;
3115}
3116
3117static inline bool __l2cap_efs_supported(struct l2cap_conn *conn)
3118{
3119 return conn->hs_enabled && conn->feat_mask & L2CAP_FEAT_EXT_FLOW;
3120}
3121
3122static void __l2cap_set_ertm_timeouts(struct l2cap_chan *chan,
3123 struct l2cap_conf_rfc *rfc)
3124{
3125 if (chan->local_amp_id != AMP_ID_BREDR && chan->hs_hcon) {
3126 u64 ertm_to = chan->hs_hcon->hdev->amp_be_flush_to;
3127
3128 /* Class 1 devices have must have ERTM timeouts
3129 * exceeding the Link Supervision Timeout. The
3130 * default Link Supervision Timeout for AMP
3131 * controllers is 10 seconds.
3132 *
3133 * Class 1 devices use 0xffffffff for their
3134 * best-effort flush timeout, so the clamping logic
3135 * will result in a timeout that meets the above
3136 * requirement. ERTM timeouts are 16-bit values, so
3137 * the maximum timeout is 65.535 seconds.
3138 */
3139
3140 /* Convert timeout to milliseconds and round */
3141 ertm_to = DIV_ROUND_UP_ULL(ertm_to, 1000);
3142
3143 /* This is the recommended formula for class 2 devices
3144 * that start ERTM timers when packets are sent to the
3145 * controller.
3146 */
3147 ertm_to = 3 * ertm_to + 500;
3148
3149 if (ertm_to > 0xffff)
3150 ertm_to = 0xffff;
3151
3152 rfc->retrans_timeout = cpu_to_le16((u16) ertm_to);
3153 rfc->monitor_timeout = rfc->retrans_timeout;
3154 } else {
3155 rfc->retrans_timeout = cpu_to_le16(L2CAP_DEFAULT_RETRANS_TO);
3156 rfc->monitor_timeout = cpu_to_le16(L2CAP_DEFAULT_MONITOR_TO);
3157 }
3158}
3159
3160static inline void l2cap_txwin_setup(struct l2cap_chan *chan)
3161{
3162 if (chan->tx_win > L2CAP_DEFAULT_TX_WINDOW &&
3163 __l2cap_ews_supported(chan->conn)) {
3164 /* use extended control field */
3165 set_bit(FLAG_EXT_CTRL, &chan->flags);
3166 chan->tx_win_max = L2CAP_DEFAULT_EXT_WINDOW;
3167 } else {
3168 chan->tx_win = min_t(u16, chan->tx_win,
3169 L2CAP_DEFAULT_TX_WINDOW);
3170 chan->tx_win_max = L2CAP_DEFAULT_TX_WINDOW;
3171 }
3172 chan->ack_win = chan->tx_win;
3173}
3174
3175static int l2cap_build_conf_req(struct l2cap_chan *chan, void *data)
3176{
3177 struct l2cap_conf_req *req = data;
3178 struct l2cap_conf_rfc rfc = { .mode = chan->mode };
3179 void *ptr = req->data;
3180 u16 size;
3181
3182 BT_DBG("chan %p", chan);
3183
3184 if (chan->num_conf_req || chan->num_conf_rsp)
3185 goto done;
3186
3187 switch (chan->mode) {
3188 case L2CAP_MODE_STREAMING:
3189 case L2CAP_MODE_ERTM:
3190 if (test_bit(CONF_STATE2_DEVICE, &chan->conf_state))
3191 break;
3192
3193 if (__l2cap_efs_supported(chan->conn))
3194 set_bit(FLAG_EFS_ENABLE, &chan->flags);
3195
3196 /* fall through */
3197 default:
3198 chan->mode = l2cap_select_mode(rfc.mode, chan->conn->feat_mask);
3199 break;
3200 }
3201
3202done:
3203 if (chan->imtu != L2CAP_DEFAULT_MTU)
3204 l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->imtu);
3205
3206 switch (chan->mode) {
3207 case L2CAP_MODE_BASIC:
3208 if (!(chan->conn->feat_mask & L2CAP_FEAT_ERTM) &&
3209 !(chan->conn->feat_mask & L2CAP_FEAT_STREAMING))
3210 break;
3211
3212 rfc.mode = L2CAP_MODE_BASIC;
3213 rfc.txwin_size = 0;
3214 rfc.max_transmit = 0;
3215 rfc.retrans_timeout = 0;
3216 rfc.monitor_timeout = 0;
3217 rfc.max_pdu_size = 0;
3218
3219 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3220 (unsigned long) &rfc);
3221 break;
3222
3223 case L2CAP_MODE_ERTM:
3224 rfc.mode = L2CAP_MODE_ERTM;
3225 rfc.max_transmit = chan->max_tx;
3226
3227 __l2cap_set_ertm_timeouts(chan, &rfc);
3228
3229 size = min_t(u16, L2CAP_DEFAULT_MAX_PDU_SIZE, chan->conn->mtu -
3230 L2CAP_EXT_HDR_SIZE - L2CAP_SDULEN_SIZE -
3231 L2CAP_FCS_SIZE);
3232 rfc.max_pdu_size = cpu_to_le16(size);
3233
3234 l2cap_txwin_setup(chan);
3235
3236 rfc.txwin_size = min_t(u16, chan->tx_win,
3237 L2CAP_DEFAULT_TX_WINDOW);
3238
3239 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3240 (unsigned long) &rfc);
3241
3242 if (test_bit(FLAG_EFS_ENABLE, &chan->flags))
3243 l2cap_add_opt_efs(&ptr, chan);
3244
3245 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
3246 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EWS, 2,
3247 chan->tx_win);
3248
3249 if (chan->conn->feat_mask & L2CAP_FEAT_FCS)
3250 if (chan->fcs == L2CAP_FCS_NONE ||
3251 test_bit(CONF_RECV_NO_FCS, &chan->conf_state)) {
3252 chan->fcs = L2CAP_FCS_NONE;
3253 l2cap_add_conf_opt(&ptr, L2CAP_CONF_FCS, 1,
3254 chan->fcs);
3255 }
3256 break;
3257
3258 case L2CAP_MODE_STREAMING:
3259 l2cap_txwin_setup(chan);
3260 rfc.mode = L2CAP_MODE_STREAMING;
3261 rfc.txwin_size = 0;
3262 rfc.max_transmit = 0;
3263 rfc.retrans_timeout = 0;
3264 rfc.monitor_timeout = 0;
3265
3266 size = min_t(u16, L2CAP_DEFAULT_MAX_PDU_SIZE, chan->conn->mtu -
3267 L2CAP_EXT_HDR_SIZE - L2CAP_SDULEN_SIZE -
3268 L2CAP_FCS_SIZE);
3269 rfc.max_pdu_size = cpu_to_le16(size);
3270
3271 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3272 (unsigned long) &rfc);
3273
3274 if (test_bit(FLAG_EFS_ENABLE, &chan->flags))
3275 l2cap_add_opt_efs(&ptr, chan);
3276
3277 if (chan->conn->feat_mask & L2CAP_FEAT_FCS)
3278 if (chan->fcs == L2CAP_FCS_NONE ||
3279 test_bit(CONF_RECV_NO_FCS, &chan->conf_state)) {
3280 chan->fcs = L2CAP_FCS_NONE;
3281 l2cap_add_conf_opt(&ptr, L2CAP_CONF_FCS, 1,
3282 chan->fcs);
3283 }
3284 break;
3285 }
3286
3287 req->dcid = cpu_to_le16(chan->dcid);
3288 req->flags = cpu_to_le16(0);
3289
3290 return ptr - data;
3291}
3292
3293static int l2cap_parse_conf_req(struct l2cap_chan *chan, void *data)
3294{
3295 struct l2cap_conf_rsp *rsp = data;
3296 void *ptr = rsp->data;
3297 void *req = chan->conf_req;
3298 int len = chan->conf_len;
3299 int type, hint, olen;
3300 unsigned long val;
3301 struct l2cap_conf_rfc rfc = { .mode = L2CAP_MODE_BASIC };
3302 struct l2cap_conf_efs efs;
3303 u8 remote_efs = 0;
3304 u16 mtu = L2CAP_DEFAULT_MTU;
3305 u16 result = L2CAP_CONF_SUCCESS;
3306 u16 size;
3307
3308 BT_DBG("chan %p", chan);
3309
3310 while (len >= L2CAP_CONF_OPT_SIZE) {
3311 len -= l2cap_get_conf_opt(&req, &type, &olen, &val);
3312
3313 hint = type & L2CAP_CONF_HINT;
3314 type &= L2CAP_CONF_MASK;
3315
3316 switch (type) {
3317 case L2CAP_CONF_MTU:
3318 mtu = val;
3319 break;
3320
3321 case L2CAP_CONF_FLUSH_TO:
3322 chan->flush_to = val;
3323 break;
3324
3325 case L2CAP_CONF_QOS:
3326 break;
3327
3328 case L2CAP_CONF_RFC:
3329 if (olen == sizeof(rfc))
3330 memcpy(&rfc, (void *) val, olen);
3331 break;
3332
3333 case L2CAP_CONF_FCS:
3334 if (val == L2CAP_FCS_NONE)
3335 set_bit(CONF_RECV_NO_FCS, &chan->conf_state);
3336 break;
3337
3338 case L2CAP_CONF_EFS:
3339 remote_efs = 1;
3340 if (olen == sizeof(efs))
3341 memcpy(&efs, (void *) val, olen);
3342 break;
3343
3344 case L2CAP_CONF_EWS:
3345 if (!chan->conn->hs_enabled)
3346 return -ECONNREFUSED;
3347
3348 set_bit(FLAG_EXT_CTRL, &chan->flags);
3349 set_bit(CONF_EWS_RECV, &chan->conf_state);
3350 chan->tx_win_max = L2CAP_DEFAULT_EXT_WINDOW;
3351 chan->remote_tx_win = val;
3352 break;
3353
3354 default:
3355 if (hint)
3356 break;
3357
3358 result = L2CAP_CONF_UNKNOWN;
3359 *((u8 *) ptr++) = type;
3360 break;
3361 }
3362 }
3363
3364 if (chan->num_conf_rsp || chan->num_conf_req > 1)
3365 goto done;
3366
3367 switch (chan->mode) {
3368 case L2CAP_MODE_STREAMING:
3369 case L2CAP_MODE_ERTM:
3370 if (!test_bit(CONF_STATE2_DEVICE, &chan->conf_state)) {
3371 chan->mode = l2cap_select_mode(rfc.mode,
3372 chan->conn->feat_mask);
3373 break;
3374 }
3375
3376 if (remote_efs) {
3377 if (__l2cap_efs_supported(chan->conn))
3378 set_bit(FLAG_EFS_ENABLE, &chan->flags);
3379 else
3380 return -ECONNREFUSED;
3381 }
3382
3383 if (chan->mode != rfc.mode)
3384 return -ECONNREFUSED;
3385
3386 break;
3387 }
3388
3389done:
3390 if (chan->mode != rfc.mode) {
3391 result = L2CAP_CONF_UNACCEPT;
3392 rfc.mode = chan->mode;
3393
3394 if (chan->num_conf_rsp == 1)
3395 return -ECONNREFUSED;
3396
3397 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3398 (unsigned long) &rfc);
3399 }
3400
3401 if (result == L2CAP_CONF_SUCCESS) {
3402 /* Configure output options and let the other side know
3403 * which ones we don't like. */
3404
3405 if (mtu < L2CAP_DEFAULT_MIN_MTU)
3406 result = L2CAP_CONF_UNACCEPT;
3407 else {
3408 chan->omtu = mtu;
3409 set_bit(CONF_MTU_DONE, &chan->conf_state);
3410 }
3411 l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->omtu);
3412
3413 if (remote_efs) {
3414 if (chan->local_stype != L2CAP_SERV_NOTRAFIC &&
3415 efs.stype != L2CAP_SERV_NOTRAFIC &&
3416 efs.stype != chan->local_stype) {
3417
3418 result = L2CAP_CONF_UNACCEPT;
3419
3420 if (chan->num_conf_req >= 1)
3421 return -ECONNREFUSED;
3422
3423 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS,
3424 sizeof(efs),
3425 (unsigned long) &efs);
3426 } else {
3427 /* Send PENDING Conf Rsp */
3428 result = L2CAP_CONF_PENDING;
3429 set_bit(CONF_LOC_CONF_PEND, &chan->conf_state);
3430 }
3431 }
3432
3433 switch (rfc.mode) {
3434 case L2CAP_MODE_BASIC:
3435 chan->fcs = L2CAP_FCS_NONE;
3436 set_bit(CONF_MODE_DONE, &chan->conf_state);
3437 break;
3438
3439 case L2CAP_MODE_ERTM:
3440 if (!test_bit(CONF_EWS_RECV, &chan->conf_state))
3441 chan->remote_tx_win = rfc.txwin_size;
3442 else
3443 rfc.txwin_size = L2CAP_DEFAULT_TX_WINDOW;
3444
3445 chan->remote_max_tx = rfc.max_transmit;
3446
3447 size = min_t(u16, le16_to_cpu(rfc.max_pdu_size),
3448 chan->conn->mtu - L2CAP_EXT_HDR_SIZE -
3449 L2CAP_SDULEN_SIZE - L2CAP_FCS_SIZE);
3450 rfc.max_pdu_size = cpu_to_le16(size);
3451 chan->remote_mps = size;
3452
3453 __l2cap_set_ertm_timeouts(chan, &rfc);
3454
3455 set_bit(CONF_MODE_DONE, &chan->conf_state);
3456
3457 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC,
3458 sizeof(rfc), (unsigned long) &rfc);
3459
3460 if (test_bit(FLAG_EFS_ENABLE, &chan->flags)) {
3461 chan->remote_id = efs.id;
3462 chan->remote_stype = efs.stype;
3463 chan->remote_msdu = le16_to_cpu(efs.msdu);
3464 chan->remote_flush_to =
3465 le32_to_cpu(efs.flush_to);
3466 chan->remote_acc_lat =
3467 le32_to_cpu(efs.acc_lat);
3468 chan->remote_sdu_itime =
3469 le32_to_cpu(efs.sdu_itime);
3470 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS,
3471 sizeof(efs),
3472 (unsigned long) &efs);
3473 }
3474 break;
3475
3476 case L2CAP_MODE_STREAMING:
3477 size = min_t(u16, le16_to_cpu(rfc.max_pdu_size),
3478 chan->conn->mtu - L2CAP_EXT_HDR_SIZE -
3479 L2CAP_SDULEN_SIZE - L2CAP_FCS_SIZE);
3480 rfc.max_pdu_size = cpu_to_le16(size);
3481 chan->remote_mps = size;
3482
3483 set_bit(CONF_MODE_DONE, &chan->conf_state);
3484
3485 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3486 (unsigned long) &rfc);
3487
3488 break;
3489
3490 default:
3491 result = L2CAP_CONF_UNACCEPT;
3492
3493 memset(&rfc, 0, sizeof(rfc));
3494 rfc.mode = chan->mode;
3495 }
3496
3497 if (result == L2CAP_CONF_SUCCESS)
3498 set_bit(CONF_OUTPUT_DONE, &chan->conf_state);
3499 }
3500 rsp->scid = cpu_to_le16(chan->dcid);
3501 rsp->result = cpu_to_le16(result);
3502 rsp->flags = cpu_to_le16(0);
3503
3504 return ptr - data;
3505}
3506
3507static int l2cap_parse_conf_rsp(struct l2cap_chan *chan, void *rsp, int len,
3508 void *data, u16 *result)
3509{
3510 struct l2cap_conf_req *req = data;
3511 void *ptr = req->data;
3512 int type, olen;
3513 unsigned long val;
3514 struct l2cap_conf_rfc rfc = { .mode = L2CAP_MODE_BASIC };
3515 struct l2cap_conf_efs efs;
3516
3517 BT_DBG("chan %p, rsp %p, len %d, req %p", chan, rsp, len, data);
3518
3519 while (len >= L2CAP_CONF_OPT_SIZE) {
3520 len -= l2cap_get_conf_opt(&rsp, &type, &olen, &val);
3521
3522 switch (type) {
3523 case L2CAP_CONF_MTU:
3524 if (val < L2CAP_DEFAULT_MIN_MTU) {
3525 *result = L2CAP_CONF_UNACCEPT;
3526 chan->imtu = L2CAP_DEFAULT_MIN_MTU;
3527 } else
3528 chan->imtu = val;
3529 l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->imtu);
3530 break;
3531
3532 case L2CAP_CONF_FLUSH_TO:
3533 chan->flush_to = val;
3534 l2cap_add_conf_opt(&ptr, L2CAP_CONF_FLUSH_TO,
3535 2, chan->flush_to);
3536 break;
3537
3538 case L2CAP_CONF_RFC:
3539 if (olen == sizeof(rfc))
3540 memcpy(&rfc, (void *)val, olen);
3541
3542 if (test_bit(CONF_STATE2_DEVICE, &chan->conf_state) &&
3543 rfc.mode != chan->mode)
3544 return -ECONNREFUSED;
3545
3546 chan->fcs = 0;
3547
3548 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC,
3549 sizeof(rfc), (unsigned long) &rfc);
3550 break;
3551
3552 case L2CAP_CONF_EWS:
3553 chan->ack_win = min_t(u16, val, chan->ack_win);
3554 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EWS, 2,
3555 chan->tx_win);
3556 break;
3557
3558 case L2CAP_CONF_EFS:
3559 if (olen == sizeof(efs))
3560 memcpy(&efs, (void *)val, olen);
3561
3562 if (chan->local_stype != L2CAP_SERV_NOTRAFIC &&
3563 efs.stype != L2CAP_SERV_NOTRAFIC &&
3564 efs.stype != chan->local_stype)
3565 return -ECONNREFUSED;
3566
3567 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS, sizeof(efs),
3568 (unsigned long) &efs);
3569 break;
3570
3571 case L2CAP_CONF_FCS:
3572 if (*result == L2CAP_CONF_PENDING)
3573 if (val == L2CAP_FCS_NONE)
3574 set_bit(CONF_RECV_NO_FCS,
3575 &chan->conf_state);
3576 break;
3577 }
3578 }
3579
3580 if (chan->mode == L2CAP_MODE_BASIC && chan->mode != rfc.mode)
3581 return -ECONNREFUSED;
3582
3583 chan->mode = rfc.mode;
3584
3585 if (*result == L2CAP_CONF_SUCCESS || *result == L2CAP_CONF_PENDING) {
3586 switch (rfc.mode) {
3587 case L2CAP_MODE_ERTM:
3588 chan->retrans_timeout = le16_to_cpu(rfc.retrans_timeout);
3589 chan->monitor_timeout = le16_to_cpu(rfc.monitor_timeout);
3590 chan->mps = le16_to_cpu(rfc.max_pdu_size);
3591 if (!test_bit(FLAG_EXT_CTRL, &chan->flags))
3592 chan->ack_win = min_t(u16, chan->ack_win,
3593 rfc.txwin_size);
3594
3595 if (test_bit(FLAG_EFS_ENABLE, &chan->flags)) {
3596 chan->local_msdu = le16_to_cpu(efs.msdu);
3597 chan->local_sdu_itime =
3598 le32_to_cpu(efs.sdu_itime);
3599 chan->local_acc_lat = le32_to_cpu(efs.acc_lat);
3600 chan->local_flush_to =
3601 le32_to_cpu(efs.flush_to);
3602 }
3603 break;
3604
3605 case L2CAP_MODE_STREAMING:
3606 chan->mps = le16_to_cpu(rfc.max_pdu_size);
3607 }
3608 }
3609
3610 req->dcid = cpu_to_le16(chan->dcid);
3611 req->flags = cpu_to_le16(0);
3612
3613 return ptr - data;
3614}
3615
3616static int l2cap_build_conf_rsp(struct l2cap_chan *chan, void *data,
3617 u16 result, u16 flags)
3618{
3619 struct l2cap_conf_rsp *rsp = data;
3620 void *ptr = rsp->data;
3621
3622 BT_DBG("chan %p", chan);
3623
3624 rsp->scid = cpu_to_le16(chan->dcid);
3625 rsp->result = cpu_to_le16(result);
3626 rsp->flags = cpu_to_le16(flags);
3627
3628 return ptr - data;
3629}
3630
3631void __l2cap_le_connect_rsp_defer(struct l2cap_chan *chan)
3632{
3633 struct l2cap_le_conn_rsp rsp;
3634 struct l2cap_conn *conn = chan->conn;
3635
3636 BT_DBG("chan %p", chan);
3637
3638 rsp.dcid = cpu_to_le16(chan->scid);
3639 rsp.mtu = cpu_to_le16(chan->imtu);
3640 rsp.mps = cpu_to_le16(chan->mps);
3641 rsp.credits = cpu_to_le16(chan->rx_credits);
3642 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
3643
3644 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CONN_RSP, sizeof(rsp),
3645 &rsp);
3646}
3647
3648void __l2cap_connect_rsp_defer(struct l2cap_chan *chan)
3649{
3650 struct l2cap_conn_rsp rsp;
3651 struct l2cap_conn *conn = chan->conn;
3652 u8 buf[128];
3653 u8 rsp_code;
3654
3655 rsp.scid = cpu_to_le16(chan->dcid);
3656 rsp.dcid = cpu_to_le16(chan->scid);
3657 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
3658 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
3659
3660 if (chan->hs_hcon)
3661 rsp_code = L2CAP_CREATE_CHAN_RSP;
3662 else
3663 rsp_code = L2CAP_CONN_RSP;
3664
3665 BT_DBG("chan %p rsp_code %u", chan, rsp_code);
3666
3667 l2cap_send_cmd(conn, chan->ident, rsp_code, sizeof(rsp), &rsp);
3668
3669 if (test_and_set_bit(CONF_REQ_SENT, &chan->conf_state))
3670 return;
3671
3672 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
3673 l2cap_build_conf_req(chan, buf), buf);
3674 chan->num_conf_req++;
3675}
3676
3677static void l2cap_conf_rfc_get(struct l2cap_chan *chan, void *rsp, int len)
3678{
3679 int type, olen;
3680 unsigned long val;
3681 /* Use sane default values in case a misbehaving remote device
3682 * did not send an RFC or extended window size option.
3683 */
3684 u16 txwin_ext = chan->ack_win;
3685 struct l2cap_conf_rfc rfc = {
3686 .mode = chan->mode,
3687 .retrans_timeout = cpu_to_le16(L2CAP_DEFAULT_RETRANS_TO),
3688 .monitor_timeout = cpu_to_le16(L2CAP_DEFAULT_MONITOR_TO),
3689 .max_pdu_size = cpu_to_le16(chan->imtu),
3690 .txwin_size = min_t(u16, chan->ack_win, L2CAP_DEFAULT_TX_WINDOW),
3691 };
3692
3693 BT_DBG("chan %p, rsp %p, len %d", chan, rsp, len);
3694
3695 if ((chan->mode != L2CAP_MODE_ERTM) && (chan->mode != L2CAP_MODE_STREAMING))
3696 return;
3697
3698 while (len >= L2CAP_CONF_OPT_SIZE) {
3699 len -= l2cap_get_conf_opt(&rsp, &type, &olen, &val);
3700
3701 switch (type) {
3702 case L2CAP_CONF_RFC:
3703 if (olen == sizeof(rfc))
3704 memcpy(&rfc, (void *)val, olen);
3705 break;
3706 case L2CAP_CONF_EWS:
3707 txwin_ext = val;
3708 break;
3709 }
3710 }
3711
3712 switch (rfc.mode) {
3713 case L2CAP_MODE_ERTM:
3714 chan->retrans_timeout = le16_to_cpu(rfc.retrans_timeout);
3715 chan->monitor_timeout = le16_to_cpu(rfc.monitor_timeout);
3716 chan->mps = le16_to_cpu(rfc.max_pdu_size);
3717 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
3718 chan->ack_win = min_t(u16, chan->ack_win, txwin_ext);
3719 else
3720 chan->ack_win = min_t(u16, chan->ack_win,
3721 rfc.txwin_size);
3722 break;
3723 case L2CAP_MODE_STREAMING:
3724 chan->mps = le16_to_cpu(rfc.max_pdu_size);
3725 }
3726}
3727
3728static inline int l2cap_command_rej(struct l2cap_conn *conn,
3729 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
3730 u8 *data)
3731{
3732 struct l2cap_cmd_rej_unk *rej = (struct l2cap_cmd_rej_unk *) data;
3733
3734 if (cmd_len < sizeof(*rej))
3735 return -EPROTO;
3736
3737 if (rej->reason != L2CAP_REJ_NOT_UNDERSTOOD)
3738 return 0;
3739
3740 if ((conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT) &&
3741 cmd->ident == conn->info_ident) {
3742 cancel_delayed_work(&conn->info_timer);
3743
3744 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
3745 conn->info_ident = 0;
3746
3747 l2cap_conn_start(conn);
3748 }
3749
3750 return 0;
3751}
3752
3753static struct l2cap_chan *l2cap_connect(struct l2cap_conn *conn,
3754 struct l2cap_cmd_hdr *cmd,
3755 u8 *data, u8 rsp_code, u8 amp_id)
3756{
3757 struct l2cap_conn_req *req = (struct l2cap_conn_req *) data;
3758 struct l2cap_conn_rsp rsp;
3759 struct l2cap_chan *chan = NULL, *pchan;
3760 int result, status = L2CAP_CS_NO_INFO;
3761
3762 u16 dcid = 0, scid = __le16_to_cpu(req->scid);
3763 __le16 psm = req->psm;
3764
3765 BT_DBG("psm 0x%2.2x scid 0x%4.4x", __le16_to_cpu(psm), scid);
3766
3767 /* Check if we have socket listening on psm */
3768 pchan = l2cap_global_chan_by_psm(BT_LISTEN, psm, &conn->hcon->src,
3769 &conn->hcon->dst, ACL_LINK);
3770 if (!pchan) {
3771 result = L2CAP_CR_BAD_PSM;
3772 goto sendresp;
3773 }
3774
3775 mutex_lock(&conn->chan_lock);
3776 l2cap_chan_lock(pchan);
3777
3778 /* Check if the ACL is secure enough (if not SDP) */
3779 if (psm != cpu_to_le16(L2CAP_PSM_SDP) &&
3780 !hci_conn_check_link_mode(conn->hcon)) {
3781 conn->disc_reason = HCI_ERROR_AUTH_FAILURE;
3782 result = L2CAP_CR_SEC_BLOCK;
3783 goto response;
3784 }
3785
3786 result = L2CAP_CR_NO_MEM;
3787
3788 /* Check if we already have channel with that dcid */
3789 if (__l2cap_get_chan_by_dcid(conn, scid))
3790 goto response;
3791
3792 chan = pchan->ops->new_connection(pchan);
3793 if (!chan)
3794 goto response;
3795
3796 /* For certain devices (ex: HID mouse), support for authentication,
3797 * pairing and bonding is optional. For such devices, inorder to avoid
3798 * the ACL alive for too long after L2CAP disconnection, reset the ACL
3799 * disc_timeout back to HCI_DISCONN_TIMEOUT during L2CAP connect.
3800 */
3801 conn->hcon->disc_timeout = HCI_DISCONN_TIMEOUT;
3802
3803 bacpy(&chan->src, &conn->hcon->src);
3804 bacpy(&chan->dst, &conn->hcon->dst);
3805 chan->src_type = bdaddr_type(conn->hcon, conn->hcon->src_type);
3806 chan->dst_type = bdaddr_type(conn->hcon, conn->hcon->dst_type);
3807 chan->psm = psm;
3808 chan->dcid = scid;
3809 chan->local_amp_id = amp_id;
3810
3811 __l2cap_chan_add(conn, chan);
3812
3813 dcid = chan->scid;
3814
3815 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
3816
3817 chan->ident = cmd->ident;
3818
3819 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE) {
3820 if (l2cap_chan_check_security(chan)) {
3821 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
3822 l2cap_state_change(chan, BT_CONNECT2);
3823 result = L2CAP_CR_PEND;
3824 status = L2CAP_CS_AUTHOR_PEND;
3825 chan->ops->defer(chan);
3826 } else {
3827 /* Force pending result for AMP controllers.
3828 * The connection will succeed after the
3829 * physical link is up.
3830 */
3831 if (amp_id == AMP_ID_BREDR) {
3832 l2cap_state_change(chan, BT_CONFIG);
3833 result = L2CAP_CR_SUCCESS;
3834 } else {
3835 l2cap_state_change(chan, BT_CONNECT2);
3836 result = L2CAP_CR_PEND;
3837 }
3838 status = L2CAP_CS_NO_INFO;
3839 }
3840 } else {
3841 l2cap_state_change(chan, BT_CONNECT2);
3842 result = L2CAP_CR_PEND;
3843 status = L2CAP_CS_AUTHEN_PEND;
3844 }
3845 } else {
3846 l2cap_state_change(chan, BT_CONNECT2);
3847 result = L2CAP_CR_PEND;
3848 status = L2CAP_CS_NO_INFO;
3849 }
3850
3851response:
3852 l2cap_chan_unlock(pchan);
3853 mutex_unlock(&conn->chan_lock);
3854
3855sendresp:
3856 rsp.scid = cpu_to_le16(scid);
3857 rsp.dcid = cpu_to_le16(dcid);
3858 rsp.result = cpu_to_le16(result);
3859 rsp.status = cpu_to_le16(status);
3860 l2cap_send_cmd(conn, cmd->ident, rsp_code, sizeof(rsp), &rsp);
3861
3862 if (result == L2CAP_CR_PEND && status == L2CAP_CS_NO_INFO) {
3863 struct l2cap_info_req info;
3864 info.type = cpu_to_le16(L2CAP_IT_FEAT_MASK);
3865
3866 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_SENT;
3867 conn->info_ident = l2cap_get_ident(conn);
3868
3869 schedule_delayed_work(&conn->info_timer, L2CAP_INFO_TIMEOUT);
3870
3871 l2cap_send_cmd(conn, conn->info_ident, L2CAP_INFO_REQ,
3872 sizeof(info), &info);
3873 }
3874
3875 if (chan && !test_bit(CONF_REQ_SENT, &chan->conf_state) &&
3876 result == L2CAP_CR_SUCCESS) {
3877 u8 buf[128];
3878 set_bit(CONF_REQ_SENT, &chan->conf_state);
3879 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
3880 l2cap_build_conf_req(chan, buf), buf);
3881 chan->num_conf_req++;
3882 }
3883
3884 return chan;
3885}
3886
3887static int l2cap_connect_req(struct l2cap_conn *conn,
3888 struct l2cap_cmd_hdr *cmd, u16 cmd_len, u8 *data)
3889{
3890 struct hci_dev *hdev = conn->hcon->hdev;
3891 struct hci_conn *hcon = conn->hcon;
3892
3893 if (cmd_len < sizeof(struct l2cap_conn_req))
3894 return -EPROTO;
3895
3896 hci_dev_lock(hdev);
3897 if (test_bit(HCI_MGMT, &hdev->dev_flags) &&
3898 !test_and_set_bit(HCI_CONN_MGMT_CONNECTED, &hcon->flags))
3899 mgmt_device_connected(hdev, &hcon->dst, hcon->type,
3900 hcon->dst_type, 0, NULL, 0,
3901 hcon->dev_class);
3902 hci_dev_unlock(hdev);
3903
3904 l2cap_connect(conn, cmd, data, L2CAP_CONN_RSP, 0);
3905 return 0;
3906}
3907
3908static int l2cap_connect_create_rsp(struct l2cap_conn *conn,
3909 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
3910 u8 *data)
3911{
3912 struct l2cap_conn_rsp *rsp = (struct l2cap_conn_rsp *) data;
3913 u16 scid, dcid, result, status;
3914 struct l2cap_chan *chan;
3915 u8 req[128];
3916 int err;
3917
3918 if (cmd_len < sizeof(*rsp))
3919 return -EPROTO;
3920
3921 scid = __le16_to_cpu(rsp->scid);
3922 dcid = __le16_to_cpu(rsp->dcid);
3923 result = __le16_to_cpu(rsp->result);
3924 status = __le16_to_cpu(rsp->status);
3925
3926 BT_DBG("dcid 0x%4.4x scid 0x%4.4x result 0x%2.2x status 0x%2.2x",
3927 dcid, scid, result, status);
3928
3929 mutex_lock(&conn->chan_lock);
3930
3931 if (scid) {
3932 chan = __l2cap_get_chan_by_scid(conn, scid);
3933 if (!chan) {
3934 err = -EBADSLT;
3935 goto unlock;
3936 }
3937 } else {
3938 chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
3939 if (!chan) {
3940 err = -EBADSLT;
3941 goto unlock;
3942 }
3943 }
3944
3945 err = 0;
3946
3947 l2cap_chan_lock(chan);
3948
3949 switch (result) {
3950 case L2CAP_CR_SUCCESS:
3951 l2cap_state_change(chan, BT_CONFIG);
3952 chan->ident = 0;
3953 chan->dcid = dcid;
3954 clear_bit(CONF_CONNECT_PEND, &chan->conf_state);
3955
3956 if (test_and_set_bit(CONF_REQ_SENT, &chan->conf_state))
3957 break;
3958
3959 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
3960 l2cap_build_conf_req(chan, req), req);
3961 chan->num_conf_req++;
3962 break;
3963
3964 case L2CAP_CR_PEND:
3965 set_bit(CONF_CONNECT_PEND, &chan->conf_state);
3966 break;
3967
3968 default:
3969 l2cap_chan_del(chan, ECONNREFUSED);
3970 break;
3971 }
3972
3973 l2cap_chan_unlock(chan);
3974
3975unlock:
3976 mutex_unlock(&conn->chan_lock);
3977
3978 return err;
3979}
3980
3981static inline void set_default_fcs(struct l2cap_chan *chan)
3982{
3983 /* FCS is enabled only in ERTM or streaming mode, if one or both
3984 * sides request it.
3985 */
3986 if (chan->mode != L2CAP_MODE_ERTM && chan->mode != L2CAP_MODE_STREAMING)
3987 chan->fcs = L2CAP_FCS_NONE;
3988 else if (!test_bit(CONF_RECV_NO_FCS, &chan->conf_state))
3989 chan->fcs = L2CAP_FCS_CRC16;
3990}
3991
3992static void l2cap_send_efs_conf_rsp(struct l2cap_chan *chan, void *data,
3993 u8 ident, u16 flags)
3994{
3995 struct l2cap_conn *conn = chan->conn;
3996
3997 BT_DBG("conn %p chan %p ident %d flags 0x%4.4x", conn, chan, ident,
3998 flags);
3999
4000 clear_bit(CONF_LOC_CONF_PEND, &chan->conf_state);
4001 set_bit(CONF_OUTPUT_DONE, &chan->conf_state);
4002
4003 l2cap_send_cmd(conn, ident, L2CAP_CONF_RSP,
4004 l2cap_build_conf_rsp(chan, data,
4005 L2CAP_CONF_SUCCESS, flags), data);
4006}
4007
4008static void cmd_reject_invalid_cid(struct l2cap_conn *conn, u8 ident,
4009 u16 scid, u16 dcid)
4010{
4011 struct l2cap_cmd_rej_cid rej;
4012
4013 rej.reason = cpu_to_le16(L2CAP_REJ_INVALID_CID);
4014 rej.scid = __cpu_to_le16(scid);
4015 rej.dcid = __cpu_to_le16(dcid);
4016
4017 l2cap_send_cmd(conn, ident, L2CAP_COMMAND_REJ, sizeof(rej), &rej);
4018}
4019
4020static inline int l2cap_config_req(struct l2cap_conn *conn,
4021 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4022 u8 *data)
4023{
4024 struct l2cap_conf_req *req = (struct l2cap_conf_req *) data;
4025 u16 dcid, flags;
4026 u8 rsp[64];
4027 struct l2cap_chan *chan;
4028 int len, err = 0;
4029
4030 if (cmd_len < sizeof(*req))
4031 return -EPROTO;
4032
4033 dcid = __le16_to_cpu(req->dcid);
4034 flags = __le16_to_cpu(req->flags);
4035
4036 BT_DBG("dcid 0x%4.4x flags 0x%2.2x", dcid, flags);
4037
4038 chan = l2cap_get_chan_by_scid(conn, dcid);
4039 if (!chan) {
4040 cmd_reject_invalid_cid(conn, cmd->ident, dcid, 0);
4041 return 0;
4042 }
4043
4044 if (chan->state != BT_CONFIG && chan->state != BT_CONNECT2) {
4045 cmd_reject_invalid_cid(conn, cmd->ident, chan->scid,
4046 chan->dcid);
4047 goto unlock;
4048 }
4049
4050 /* Reject if config buffer is too small. */
4051 len = cmd_len - sizeof(*req);
4052 if (chan->conf_len + len > sizeof(chan->conf_req)) {
4053 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP,
4054 l2cap_build_conf_rsp(chan, rsp,
4055 L2CAP_CONF_REJECT, flags), rsp);
4056 goto unlock;
4057 }
4058
4059 /* Store config. */
4060 memcpy(chan->conf_req + chan->conf_len, req->data, len);
4061 chan->conf_len += len;
4062
4063 if (flags & L2CAP_CONF_FLAG_CONTINUATION) {
4064 /* Incomplete config. Send empty response. */
4065 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP,
4066 l2cap_build_conf_rsp(chan, rsp,
4067 L2CAP_CONF_SUCCESS, flags), rsp);
4068 goto unlock;
4069 }
4070
4071 /* Complete config. */
4072 len = l2cap_parse_conf_req(chan, rsp);
4073 if (len < 0) {
4074 l2cap_send_disconn_req(chan, ECONNRESET);
4075 goto unlock;
4076 }
4077
4078 chan->ident = cmd->ident;
4079 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP, len, rsp);
4080 chan->num_conf_rsp++;
4081
4082 /* Reset config buffer. */
4083 chan->conf_len = 0;
4084
4085 if (!test_bit(CONF_OUTPUT_DONE, &chan->conf_state))
4086 goto unlock;
4087
4088 if (test_bit(CONF_INPUT_DONE, &chan->conf_state)) {
4089 set_default_fcs(chan);
4090
4091 if (chan->mode == L2CAP_MODE_ERTM ||
4092 chan->mode == L2CAP_MODE_STREAMING)
4093 err = l2cap_ertm_init(chan);
4094
4095 if (err < 0)
4096 l2cap_send_disconn_req(chan, -err);
4097 else
4098 l2cap_chan_ready(chan);
4099
4100 goto unlock;
4101 }
4102
4103 if (!test_and_set_bit(CONF_REQ_SENT, &chan->conf_state)) {
4104 u8 buf[64];
4105 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
4106 l2cap_build_conf_req(chan, buf), buf);
4107 chan->num_conf_req++;
4108 }
4109
4110 /* Got Conf Rsp PENDING from remote side and asume we sent
4111 Conf Rsp PENDING in the code above */
4112 if (test_bit(CONF_REM_CONF_PEND, &chan->conf_state) &&
4113 test_bit(CONF_LOC_CONF_PEND, &chan->conf_state)) {
4114
4115 /* check compatibility */
4116
4117 /* Send rsp for BR/EDR channel */
4118 if (!chan->hs_hcon)
4119 l2cap_send_efs_conf_rsp(chan, rsp, cmd->ident, flags);
4120 else
4121 chan->ident = cmd->ident;
4122 }
4123
4124unlock:
4125 l2cap_chan_unlock(chan);
4126 return err;
4127}
4128
4129static inline int l2cap_config_rsp(struct l2cap_conn *conn,
4130 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4131 u8 *data)
4132{
4133 struct l2cap_conf_rsp *rsp = (struct l2cap_conf_rsp *)data;
4134 u16 scid, flags, result;
4135 struct l2cap_chan *chan;
4136 int len = cmd_len - sizeof(*rsp);
4137 int err = 0;
4138
4139 if (cmd_len < sizeof(*rsp))
4140 return -EPROTO;
4141
4142 scid = __le16_to_cpu(rsp->scid);
4143 flags = __le16_to_cpu(rsp->flags);
4144 result = __le16_to_cpu(rsp->result);
4145
4146 BT_DBG("scid 0x%4.4x flags 0x%2.2x result 0x%2.2x len %d", scid, flags,
4147 result, len);
4148
4149 chan = l2cap_get_chan_by_scid(conn, scid);
4150 if (!chan)
4151 return 0;
4152
4153 switch (result) {
4154 case L2CAP_CONF_SUCCESS:
4155 l2cap_conf_rfc_get(chan, rsp->data, len);
4156 clear_bit(CONF_REM_CONF_PEND, &chan->conf_state);
4157 break;
4158
4159 case L2CAP_CONF_PENDING:
4160 set_bit(CONF_REM_CONF_PEND, &chan->conf_state);
4161
4162 if (test_bit(CONF_LOC_CONF_PEND, &chan->conf_state)) {
4163 char buf[64];
4164
4165 len = l2cap_parse_conf_rsp(chan, rsp->data, len,
4166 buf, &result);
4167 if (len < 0) {
4168 l2cap_send_disconn_req(chan, ECONNRESET);
4169 goto done;
4170 }
4171
4172 if (!chan->hs_hcon) {
4173 l2cap_send_efs_conf_rsp(chan, buf, cmd->ident,
4174 0);
4175 } else {
4176 if (l2cap_check_efs(chan)) {
4177 amp_create_logical_link(chan);
4178 chan->ident = cmd->ident;
4179 }
4180 }
4181 }
4182 goto done;
4183
4184 case L2CAP_CONF_UNACCEPT:
4185 if (chan->num_conf_rsp <= L2CAP_CONF_MAX_CONF_RSP) {
4186 char req[64];
4187
4188 if (len > sizeof(req) - sizeof(struct l2cap_conf_req)) {
4189 l2cap_send_disconn_req(chan, ECONNRESET);
4190 goto done;
4191 }
4192
4193 /* throw out any old stored conf requests */
4194 result = L2CAP_CONF_SUCCESS;
4195 len = l2cap_parse_conf_rsp(chan, rsp->data, len,
4196 req, &result);
4197 if (len < 0) {
4198 l2cap_send_disconn_req(chan, ECONNRESET);
4199 goto done;
4200 }
4201
4202 l2cap_send_cmd(conn, l2cap_get_ident(conn),
4203 L2CAP_CONF_REQ, len, req);
4204 chan->num_conf_req++;
4205 if (result != L2CAP_CONF_SUCCESS)
4206 goto done;
4207 break;
4208 }
4209
4210 default:
4211 l2cap_chan_set_err(chan, ECONNRESET);
4212
4213 __set_chan_timer(chan, L2CAP_DISC_REJ_TIMEOUT);
4214 l2cap_send_disconn_req(chan, ECONNRESET);
4215 goto done;
4216 }
4217
4218 if (flags & L2CAP_CONF_FLAG_CONTINUATION)
4219 goto done;
4220
4221 set_bit(CONF_INPUT_DONE, &chan->conf_state);
4222
4223 if (test_bit(CONF_OUTPUT_DONE, &chan->conf_state)) {
4224 set_default_fcs(chan);
4225
4226 if (chan->mode == L2CAP_MODE_ERTM ||
4227 chan->mode == L2CAP_MODE_STREAMING)
4228 err = l2cap_ertm_init(chan);
4229
4230 if (err < 0)
4231 l2cap_send_disconn_req(chan, -err);
4232 else
4233 l2cap_chan_ready(chan);
4234 }
4235
4236done:
4237 l2cap_chan_unlock(chan);
4238 return err;
4239}
4240
4241static inline int l2cap_disconnect_req(struct l2cap_conn *conn,
4242 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4243 u8 *data)
4244{
4245 struct l2cap_disconn_req *req = (struct l2cap_disconn_req *) data;
4246 struct l2cap_disconn_rsp rsp;
4247 u16 dcid, scid;
4248 struct l2cap_chan *chan;
4249
4250 if (cmd_len != sizeof(*req))
4251 return -EPROTO;
4252
4253 scid = __le16_to_cpu(req->scid);
4254 dcid = __le16_to_cpu(req->dcid);
4255
4256 BT_DBG("scid 0x%4.4x dcid 0x%4.4x", scid, dcid);
4257
4258 mutex_lock(&conn->chan_lock);
4259
4260 chan = __l2cap_get_chan_by_scid(conn, dcid);
4261 if (!chan) {
4262 mutex_unlock(&conn->chan_lock);
4263 cmd_reject_invalid_cid(conn, cmd->ident, dcid, scid);
4264 return 0;
4265 }
4266
4267 l2cap_chan_lock(chan);
4268
4269 rsp.dcid = cpu_to_le16(chan->scid);
4270 rsp.scid = cpu_to_le16(chan->dcid);
4271 l2cap_send_cmd(conn, cmd->ident, L2CAP_DISCONN_RSP, sizeof(rsp), &rsp);
4272
4273 chan->ops->set_shutdown(chan);
4274
4275 l2cap_chan_hold(chan);
4276 l2cap_chan_del(chan, ECONNRESET);
4277
4278 l2cap_chan_unlock(chan);
4279
4280 chan->ops->close(chan);
4281 l2cap_chan_put(chan);
4282
4283 mutex_unlock(&conn->chan_lock);
4284
4285 return 0;
4286}
4287
4288static inline int l2cap_disconnect_rsp(struct l2cap_conn *conn,
4289 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4290 u8 *data)
4291{
4292 struct l2cap_disconn_rsp *rsp = (struct l2cap_disconn_rsp *) data;
4293 u16 dcid, scid;
4294 struct l2cap_chan *chan;
4295
4296 if (cmd_len != sizeof(*rsp))
4297 return -EPROTO;
4298
4299 scid = __le16_to_cpu(rsp->scid);
4300 dcid = __le16_to_cpu(rsp->dcid);
4301
4302 BT_DBG("dcid 0x%4.4x scid 0x%4.4x", dcid, scid);
4303
4304 mutex_lock(&conn->chan_lock);
4305
4306 chan = __l2cap_get_chan_by_scid(conn, scid);
4307 if (!chan) {
4308 mutex_unlock(&conn->chan_lock);
4309 return 0;
4310 }
4311
4312 l2cap_chan_lock(chan);
4313
4314 l2cap_chan_hold(chan);
4315 l2cap_chan_del(chan, 0);
4316
4317 l2cap_chan_unlock(chan);
4318
4319 chan->ops->close(chan);
4320 l2cap_chan_put(chan);
4321
4322 mutex_unlock(&conn->chan_lock);
4323
4324 return 0;
4325}
4326
4327static inline int l2cap_information_req(struct l2cap_conn *conn,
4328 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4329 u8 *data)
4330{
4331 struct l2cap_info_req *req = (struct l2cap_info_req *) data;
4332 u16 type;
4333
4334 if (cmd_len != sizeof(*req))
4335 return -EPROTO;
4336
4337 type = __le16_to_cpu(req->type);
4338
4339 BT_DBG("type 0x%4.4x", type);
4340
4341 if (type == L2CAP_IT_FEAT_MASK) {
4342 u8 buf[8];
4343 u32 feat_mask = l2cap_feat_mask;
4344 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) buf;
4345 rsp->type = cpu_to_le16(L2CAP_IT_FEAT_MASK);
4346 rsp->result = cpu_to_le16(L2CAP_IR_SUCCESS);
4347 if (!disable_ertm)
4348 feat_mask |= L2CAP_FEAT_ERTM | L2CAP_FEAT_STREAMING
4349 | L2CAP_FEAT_FCS;
4350 if (conn->hs_enabled)
4351 feat_mask |= L2CAP_FEAT_EXT_FLOW
4352 | L2CAP_FEAT_EXT_WINDOW;
4353
4354 put_unaligned_le32(feat_mask, rsp->data);
4355 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(buf),
4356 buf);
4357 } else if (type == L2CAP_IT_FIXED_CHAN) {
4358 u8 buf[12];
4359 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) buf;
4360
4361 if (conn->hs_enabled)
4362 l2cap_fixed_chan[0] |= L2CAP_FC_A2MP;
4363 else
4364 l2cap_fixed_chan[0] &= ~L2CAP_FC_A2MP;
4365
4366 rsp->type = cpu_to_le16(L2CAP_IT_FIXED_CHAN);
4367 rsp->result = cpu_to_le16(L2CAP_IR_SUCCESS);
4368 memcpy(rsp->data, l2cap_fixed_chan, sizeof(l2cap_fixed_chan));
4369 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(buf),
4370 buf);
4371 } else {
4372 struct l2cap_info_rsp rsp;
4373 rsp.type = cpu_to_le16(type);
4374 rsp.result = cpu_to_le16(L2CAP_IR_NOTSUPP);
4375 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(rsp),
4376 &rsp);
4377 }
4378
4379 return 0;
4380}
4381
4382static inline int l2cap_information_rsp(struct l2cap_conn *conn,
4383 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4384 u8 *data)
4385{
4386 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) data;
4387 u16 type, result;
4388
4389 if (cmd_len < sizeof(*rsp))
4390 return -EPROTO;
4391
4392 type = __le16_to_cpu(rsp->type);
4393 result = __le16_to_cpu(rsp->result);
4394
4395 BT_DBG("type 0x%4.4x result 0x%2.2x", type, result);
4396
4397 /* L2CAP Info req/rsp are unbound to channels, add extra checks */
4398 if (cmd->ident != conn->info_ident ||
4399 conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE)
4400 return 0;
4401
4402 cancel_delayed_work(&conn->info_timer);
4403
4404 if (result != L2CAP_IR_SUCCESS) {
4405 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4406 conn->info_ident = 0;
4407
4408 l2cap_conn_start(conn);
4409
4410 return 0;
4411 }
4412
4413 switch (type) {
4414 case L2CAP_IT_FEAT_MASK:
4415 conn->feat_mask = get_unaligned_le32(rsp->data);
4416
4417 if (conn->feat_mask & L2CAP_FEAT_FIXED_CHAN) {
4418 struct l2cap_info_req req;
4419 req.type = cpu_to_le16(L2CAP_IT_FIXED_CHAN);
4420
4421 conn->info_ident = l2cap_get_ident(conn);
4422
4423 l2cap_send_cmd(conn, conn->info_ident,
4424 L2CAP_INFO_REQ, sizeof(req), &req);
4425 } else {
4426 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4427 conn->info_ident = 0;
4428
4429 l2cap_conn_start(conn);
4430 }
4431 break;
4432
4433 case L2CAP_IT_FIXED_CHAN:
4434 conn->fixed_chan_mask = rsp->data[0];
4435 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4436 conn->info_ident = 0;
4437
4438 l2cap_conn_start(conn);
4439 break;
4440 }
4441
4442 return 0;
4443}
4444
4445static int l2cap_create_channel_req(struct l2cap_conn *conn,
4446 struct l2cap_cmd_hdr *cmd,
4447 u16 cmd_len, void *data)
4448{
4449 struct l2cap_create_chan_req *req = data;
4450 struct l2cap_create_chan_rsp rsp;
4451 struct l2cap_chan *chan;
4452 struct hci_dev *hdev;
4453 u16 psm, scid;
4454
4455 if (cmd_len != sizeof(*req))
4456 return -EPROTO;
4457
4458 if (!conn->hs_enabled)
4459 return -EINVAL;
4460
4461 psm = le16_to_cpu(req->psm);
4462 scid = le16_to_cpu(req->scid);
4463
4464 BT_DBG("psm 0x%2.2x, scid 0x%4.4x, amp_id %d", psm, scid, req->amp_id);
4465
4466 /* For controller id 0 make BR/EDR connection */
4467 if (req->amp_id == AMP_ID_BREDR) {
4468 l2cap_connect(conn, cmd, data, L2CAP_CREATE_CHAN_RSP,
4469 req->amp_id);
4470 return 0;
4471 }
4472
4473 /* Validate AMP controller id */
4474 hdev = hci_dev_get(req->amp_id);
4475 if (!hdev)
4476 goto error;
4477
4478 if (hdev->dev_type != HCI_AMP || !test_bit(HCI_UP, &hdev->flags)) {
4479 hci_dev_put(hdev);
4480 goto error;
4481 }
4482
4483 chan = l2cap_connect(conn, cmd, data, L2CAP_CREATE_CHAN_RSP,
4484 req->amp_id);
4485 if (chan) {
4486 struct amp_mgr *mgr = conn->hcon->amp_mgr;
4487 struct hci_conn *hs_hcon;
4488
4489 hs_hcon = hci_conn_hash_lookup_ba(hdev, AMP_LINK,
4490 &conn->hcon->dst);
4491 if (!hs_hcon) {
4492 hci_dev_put(hdev);
4493 cmd_reject_invalid_cid(conn, cmd->ident, chan->scid,
4494 chan->dcid);
4495 return 0;
4496 }
4497
4498 BT_DBG("mgr %p bredr_chan %p hs_hcon %p", mgr, chan, hs_hcon);
4499
4500 mgr->bredr_chan = chan;
4501 chan->hs_hcon = hs_hcon;
4502 chan->fcs = L2CAP_FCS_NONE;
4503 conn->mtu = hdev->block_mtu;
4504 }
4505
4506 hci_dev_put(hdev);
4507
4508 return 0;
4509
4510error:
4511 rsp.dcid = 0;
4512 rsp.scid = cpu_to_le16(scid);
4513 rsp.result = cpu_to_le16(L2CAP_CR_BAD_AMP);
4514 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
4515
4516 l2cap_send_cmd(conn, cmd->ident, L2CAP_CREATE_CHAN_RSP,
4517 sizeof(rsp), &rsp);
4518
4519 return 0;
4520}
4521
4522static void l2cap_send_move_chan_req(struct l2cap_chan *chan, u8 dest_amp_id)
4523{
4524 struct l2cap_move_chan_req req;
4525 u8 ident;
4526
4527 BT_DBG("chan %p, dest_amp_id %d", chan, dest_amp_id);
4528
4529 ident = l2cap_get_ident(chan->conn);
4530 chan->ident = ident;
4531
4532 req.icid = cpu_to_le16(chan->scid);
4533 req.dest_amp_id = dest_amp_id;
4534
4535 l2cap_send_cmd(chan->conn, ident, L2CAP_MOVE_CHAN_REQ, sizeof(req),
4536 &req);
4537
4538 __set_chan_timer(chan, L2CAP_MOVE_TIMEOUT);
4539}
4540
4541static void l2cap_send_move_chan_rsp(struct l2cap_chan *chan, u16 result)
4542{
4543 struct l2cap_move_chan_rsp rsp;
4544
4545 BT_DBG("chan %p, result 0x%4.4x", chan, result);
4546
4547 rsp.icid = cpu_to_le16(chan->dcid);
4548 rsp.result = cpu_to_le16(result);
4549
4550 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_MOVE_CHAN_RSP,
4551 sizeof(rsp), &rsp);
4552}
4553
4554static void l2cap_send_move_chan_cfm(struct l2cap_chan *chan, u16 result)
4555{
4556 struct l2cap_move_chan_cfm cfm;
4557
4558 BT_DBG("chan %p, result 0x%4.4x", chan, result);
4559
4560 chan->ident = l2cap_get_ident(chan->conn);
4561
4562 cfm.icid = cpu_to_le16(chan->scid);
4563 cfm.result = cpu_to_le16(result);
4564
4565 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_MOVE_CHAN_CFM,
4566 sizeof(cfm), &cfm);
4567
4568 __set_chan_timer(chan, L2CAP_MOVE_TIMEOUT);
4569}
4570
4571static void l2cap_send_move_chan_cfm_icid(struct l2cap_conn *conn, u16 icid)
4572{
4573 struct l2cap_move_chan_cfm cfm;
4574
4575 BT_DBG("conn %p, icid 0x%4.4x", conn, icid);
4576
4577 cfm.icid = cpu_to_le16(icid);
4578 cfm.result = cpu_to_le16(L2CAP_MC_UNCONFIRMED);
4579
4580 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_MOVE_CHAN_CFM,
4581 sizeof(cfm), &cfm);
4582}
4583
4584static void l2cap_send_move_chan_cfm_rsp(struct l2cap_conn *conn, u8 ident,
4585 u16 icid)
4586{
4587 struct l2cap_move_chan_cfm_rsp rsp;
4588
4589 BT_DBG("icid 0x%4.4x", icid);
4590
4591 rsp.icid = cpu_to_le16(icid);
4592 l2cap_send_cmd(conn, ident, L2CAP_MOVE_CHAN_CFM_RSP, sizeof(rsp), &rsp);
4593}
4594
4595static void __release_logical_link(struct l2cap_chan *chan)
4596{
4597 chan->hs_hchan = NULL;
4598 chan->hs_hcon = NULL;
4599
4600 /* Placeholder - release the logical link */
4601}
4602
4603static void l2cap_logical_fail(struct l2cap_chan *chan)
4604{
4605 /* Logical link setup failed */
4606 if (chan->state != BT_CONNECTED) {
4607 /* Create channel failure, disconnect */
4608 l2cap_send_disconn_req(chan, ECONNRESET);
4609 return;
4610 }
4611
4612 switch (chan->move_role) {
4613 case L2CAP_MOVE_ROLE_RESPONDER:
4614 l2cap_move_done(chan);
4615 l2cap_send_move_chan_rsp(chan, L2CAP_MR_NOT_SUPP);
4616 break;
4617 case L2CAP_MOVE_ROLE_INITIATOR:
4618 if (chan->move_state == L2CAP_MOVE_WAIT_LOGICAL_COMP ||
4619 chan->move_state == L2CAP_MOVE_WAIT_LOGICAL_CFM) {
4620 /* Remote has only sent pending or
4621 * success responses, clean up
4622 */
4623 l2cap_move_done(chan);
4624 }
4625
4626 /* Other amp move states imply that the move
4627 * has already aborted
4628 */
4629 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
4630 break;
4631 }
4632}
4633
4634static void l2cap_logical_finish_create(struct l2cap_chan *chan,
4635 struct hci_chan *hchan)
4636{
4637 struct l2cap_conf_rsp rsp;
4638
4639 chan->hs_hchan = hchan;
4640 chan->hs_hcon->l2cap_data = chan->conn;
4641
4642 l2cap_send_efs_conf_rsp(chan, &rsp, chan->ident, 0);
4643
4644 if (test_bit(CONF_INPUT_DONE, &chan->conf_state)) {
4645 int err;
4646
4647 set_default_fcs(chan);
4648
4649 err = l2cap_ertm_init(chan);
4650 if (err < 0)
4651 l2cap_send_disconn_req(chan, -err);
4652 else
4653 l2cap_chan_ready(chan);
4654 }
4655}
4656
4657static void l2cap_logical_finish_move(struct l2cap_chan *chan,
4658 struct hci_chan *hchan)
4659{
4660 chan->hs_hcon = hchan->conn;
4661 chan->hs_hcon->l2cap_data = chan->conn;
4662
4663 BT_DBG("move_state %d", chan->move_state);
4664
4665 switch (chan->move_state) {
4666 case L2CAP_MOVE_WAIT_LOGICAL_COMP:
4667 /* Move confirm will be sent after a success
4668 * response is received
4669 */
4670 chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
4671 break;
4672 case L2CAP_MOVE_WAIT_LOGICAL_CFM:
4673 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
4674 chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
4675 } else if (chan->move_role == L2CAP_MOVE_ROLE_INITIATOR) {
4676 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM_RSP;
4677 l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
4678 } else if (chan->move_role == L2CAP_MOVE_ROLE_RESPONDER) {
4679 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
4680 l2cap_send_move_chan_rsp(chan, L2CAP_MR_SUCCESS);
4681 }
4682 break;
4683 default:
4684 /* Move was not in expected state, free the channel */
4685 __release_logical_link(chan);
4686
4687 chan->move_state = L2CAP_MOVE_STABLE;
4688 }
4689}
4690
4691/* Call with chan locked */
4692void l2cap_logical_cfm(struct l2cap_chan *chan, struct hci_chan *hchan,
4693 u8 status)
4694{
4695 BT_DBG("chan %p, hchan %p, status %d", chan, hchan, status);
4696
4697 if (status) {
4698 l2cap_logical_fail(chan);
4699 __release_logical_link(chan);
4700 return;
4701 }
4702
4703 if (chan->state != BT_CONNECTED) {
4704 /* Ignore logical link if channel is on BR/EDR */
4705 if (chan->local_amp_id != AMP_ID_BREDR)
4706 l2cap_logical_finish_create(chan, hchan);
4707 } else {
4708 l2cap_logical_finish_move(chan, hchan);
4709 }
4710}
4711
4712void l2cap_move_start(struct l2cap_chan *chan)
4713{
4714 BT_DBG("chan %p", chan);
4715
4716 if (chan->local_amp_id == AMP_ID_BREDR) {
4717 if (chan->chan_policy != BT_CHANNEL_POLICY_AMP_PREFERRED)
4718 return;
4719 chan->move_role = L2CAP_MOVE_ROLE_INITIATOR;
4720 chan->move_state = L2CAP_MOVE_WAIT_PREPARE;
4721 /* Placeholder - start physical link setup */
4722 } else {
4723 chan->move_role = L2CAP_MOVE_ROLE_INITIATOR;
4724 chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
4725 chan->move_id = 0;
4726 l2cap_move_setup(chan);
4727 l2cap_send_move_chan_req(chan, 0);
4728 }
4729}
4730
4731static void l2cap_do_create(struct l2cap_chan *chan, int result,
4732 u8 local_amp_id, u8 remote_amp_id)
4733{
4734 BT_DBG("chan %p state %s %u -> %u", chan, state_to_string(chan->state),
4735 local_amp_id, remote_amp_id);
4736
4737 chan->fcs = L2CAP_FCS_NONE;
4738
4739 /* Outgoing channel on AMP */
4740 if (chan->state == BT_CONNECT) {
4741 if (result == L2CAP_CR_SUCCESS) {
4742 chan->local_amp_id = local_amp_id;
4743 l2cap_send_create_chan_req(chan, remote_amp_id);
4744 } else {
4745 /* Revert to BR/EDR connect */
4746 l2cap_send_conn_req(chan);
4747 }
4748
4749 return;
4750 }
4751
4752 /* Incoming channel on AMP */
4753 if (__l2cap_no_conn_pending(chan)) {
4754 struct l2cap_conn_rsp rsp;
4755 char buf[128];
4756 rsp.scid = cpu_to_le16(chan->dcid);
4757 rsp.dcid = cpu_to_le16(chan->scid);
4758
4759 if (result == L2CAP_CR_SUCCESS) {
4760 /* Send successful response */
4761 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
4762 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
4763 } else {
4764 /* Send negative response */
4765 rsp.result = cpu_to_le16(L2CAP_CR_NO_MEM);
4766 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
4767 }
4768
4769 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_CREATE_CHAN_RSP,
4770 sizeof(rsp), &rsp);
4771
4772 if (result == L2CAP_CR_SUCCESS) {
4773 l2cap_state_change(chan, BT_CONFIG);
4774 set_bit(CONF_REQ_SENT, &chan->conf_state);
4775 l2cap_send_cmd(chan->conn, l2cap_get_ident(chan->conn),
4776 L2CAP_CONF_REQ,
4777 l2cap_build_conf_req(chan, buf), buf);
4778 chan->num_conf_req++;
4779 }
4780 }
4781}
4782
4783static void l2cap_do_move_initiate(struct l2cap_chan *chan, u8 local_amp_id,
4784 u8 remote_amp_id)
4785{
4786 l2cap_move_setup(chan);
4787 chan->move_id = local_amp_id;
4788 chan->move_state = L2CAP_MOVE_WAIT_RSP;
4789
4790 l2cap_send_move_chan_req(chan, remote_amp_id);
4791}
4792
4793static void l2cap_do_move_respond(struct l2cap_chan *chan, int result)
4794{
4795 struct hci_chan *hchan = NULL;
4796
4797 /* Placeholder - get hci_chan for logical link */
4798
4799 if (hchan) {
4800 if (hchan->state == BT_CONNECTED) {
4801 /* Logical link is ready to go */
4802 chan->hs_hcon = hchan->conn;
4803 chan->hs_hcon->l2cap_data = chan->conn;
4804 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
4805 l2cap_send_move_chan_rsp(chan, L2CAP_MR_SUCCESS);
4806
4807 l2cap_logical_cfm(chan, hchan, L2CAP_MR_SUCCESS);
4808 } else {
4809 /* Wait for logical link to be ready */
4810 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
4811 }
4812 } else {
4813 /* Logical link not available */
4814 l2cap_send_move_chan_rsp(chan, L2CAP_MR_NOT_ALLOWED);
4815 }
4816}
4817
4818static void l2cap_do_move_cancel(struct l2cap_chan *chan, int result)
4819{
4820 if (chan->move_role == L2CAP_MOVE_ROLE_RESPONDER) {
4821 u8 rsp_result;
4822 if (result == -EINVAL)
4823 rsp_result = L2CAP_MR_BAD_ID;
4824 else
4825 rsp_result = L2CAP_MR_NOT_ALLOWED;
4826
4827 l2cap_send_move_chan_rsp(chan, rsp_result);
4828 }
4829
4830 chan->move_role = L2CAP_MOVE_ROLE_NONE;
4831 chan->move_state = L2CAP_MOVE_STABLE;
4832
4833 /* Restart data transmission */
4834 l2cap_ertm_send(chan);
4835}
4836
4837/* Invoke with locked chan */
4838void __l2cap_physical_cfm(struct l2cap_chan *chan, int result)
4839{
4840 u8 local_amp_id = chan->local_amp_id;
4841 u8 remote_amp_id = chan->remote_amp_id;
4842
4843 BT_DBG("chan %p, result %d, local_amp_id %d, remote_amp_id %d",
4844 chan, result, local_amp_id, remote_amp_id);
4845
4846 if (chan->state == BT_DISCONN || chan->state == BT_CLOSED) {
4847 l2cap_chan_unlock(chan);
4848 return;
4849 }
4850
4851 if (chan->state != BT_CONNECTED) {
4852 l2cap_do_create(chan, result, local_amp_id, remote_amp_id);
4853 } else if (result != L2CAP_MR_SUCCESS) {
4854 l2cap_do_move_cancel(chan, result);
4855 } else {
4856 switch (chan->move_role) {
4857 case L2CAP_MOVE_ROLE_INITIATOR:
4858 l2cap_do_move_initiate(chan, local_amp_id,
4859 remote_amp_id);
4860 break;
4861 case L2CAP_MOVE_ROLE_RESPONDER:
4862 l2cap_do_move_respond(chan, result);
4863 break;
4864 default:
4865 l2cap_do_move_cancel(chan, result);
4866 break;
4867 }
4868 }
4869}
4870
4871static inline int l2cap_move_channel_req(struct l2cap_conn *conn,
4872 struct l2cap_cmd_hdr *cmd,
4873 u16 cmd_len, void *data)
4874{
4875 struct l2cap_move_chan_req *req = data;
4876 struct l2cap_move_chan_rsp rsp;
4877 struct l2cap_chan *chan;
4878 u16 icid = 0;
4879 u16 result = L2CAP_MR_NOT_ALLOWED;
4880
4881 if (cmd_len != sizeof(*req))
4882 return -EPROTO;
4883
4884 icid = le16_to_cpu(req->icid);
4885
4886 BT_DBG("icid 0x%4.4x, dest_amp_id %d", icid, req->dest_amp_id);
4887
4888 if (!conn->hs_enabled)
4889 return -EINVAL;
4890
4891 chan = l2cap_get_chan_by_dcid(conn, icid);
4892 if (!chan) {
4893 rsp.icid = cpu_to_le16(icid);
4894 rsp.result = cpu_to_le16(L2CAP_MR_NOT_ALLOWED);
4895 l2cap_send_cmd(conn, cmd->ident, L2CAP_MOVE_CHAN_RSP,
4896 sizeof(rsp), &rsp);
4897 return 0;
4898 }
4899
4900 chan->ident = cmd->ident;
4901
4902 if (chan->scid < L2CAP_CID_DYN_START ||
4903 chan->chan_policy == BT_CHANNEL_POLICY_BREDR_ONLY ||
4904 (chan->mode != L2CAP_MODE_ERTM &&
4905 chan->mode != L2CAP_MODE_STREAMING)) {
4906 result = L2CAP_MR_NOT_ALLOWED;
4907 goto send_move_response;
4908 }
4909
4910 if (chan->local_amp_id == req->dest_amp_id) {
4911 result = L2CAP_MR_SAME_ID;
4912 goto send_move_response;
4913 }
4914
4915 if (req->dest_amp_id != AMP_ID_BREDR) {
4916 struct hci_dev *hdev;
4917 hdev = hci_dev_get(req->dest_amp_id);
4918 if (!hdev || hdev->dev_type != HCI_AMP ||
4919 !test_bit(HCI_UP, &hdev->flags)) {
4920 if (hdev)
4921 hci_dev_put(hdev);
4922
4923 result = L2CAP_MR_BAD_ID;
4924 goto send_move_response;
4925 }
4926 hci_dev_put(hdev);
4927 }
4928
4929 /* Detect a move collision. Only send a collision response
4930 * if this side has "lost", otherwise proceed with the move.
4931 * The winner has the larger bd_addr.
4932 */
4933 if ((__chan_is_moving(chan) ||
4934 chan->move_role != L2CAP_MOVE_ROLE_NONE) &&
4935 bacmp(&conn->hcon->src, &conn->hcon->dst) > 0) {
4936 result = L2CAP_MR_COLLISION;
4937 goto send_move_response;
4938 }
4939
4940 chan->move_role = L2CAP_MOVE_ROLE_RESPONDER;
4941 l2cap_move_setup(chan);
4942 chan->move_id = req->dest_amp_id;
4943 icid = chan->dcid;
4944
4945 if (req->dest_amp_id == AMP_ID_BREDR) {
4946 /* Moving to BR/EDR */
4947 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
4948 chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
4949 result = L2CAP_MR_PEND;
4950 } else {
4951 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
4952 result = L2CAP_MR_SUCCESS;
4953 }
4954 } else {
4955 chan->move_state = L2CAP_MOVE_WAIT_PREPARE;
4956 /* Placeholder - uncomment when amp functions are available */
4957 /*amp_accept_physical(chan, req->dest_amp_id);*/
4958 result = L2CAP_MR_PEND;
4959 }
4960
4961send_move_response:
4962 l2cap_send_move_chan_rsp(chan, result);
4963
4964 l2cap_chan_unlock(chan);
4965
4966 return 0;
4967}
4968
4969static void l2cap_move_continue(struct l2cap_conn *conn, u16 icid, u16 result)
4970{
4971 struct l2cap_chan *chan;
4972 struct hci_chan *hchan = NULL;
4973
4974 chan = l2cap_get_chan_by_scid(conn, icid);
4975 if (!chan) {
4976 l2cap_send_move_chan_cfm_icid(conn, icid);
4977 return;
4978 }
4979
4980 __clear_chan_timer(chan);
4981 if (result == L2CAP_MR_PEND)
4982 __set_chan_timer(chan, L2CAP_MOVE_ERTX_TIMEOUT);
4983
4984 switch (chan->move_state) {
4985 case L2CAP_MOVE_WAIT_LOGICAL_COMP:
4986 /* Move confirm will be sent when logical link
4987 * is complete.
4988 */
4989 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
4990 break;
4991 case L2CAP_MOVE_WAIT_RSP_SUCCESS:
4992 if (result == L2CAP_MR_PEND) {
4993 break;
4994 } else if (test_bit(CONN_LOCAL_BUSY,
4995 &chan->conn_state)) {
4996 chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
4997 } else {
4998 /* Logical link is up or moving to BR/EDR,
4999 * proceed with move
5000 */
5001 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM_RSP;
5002 l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
5003 }
5004 break;
5005 case L2CAP_MOVE_WAIT_RSP:
5006 /* Moving to AMP */
5007 if (result == L2CAP_MR_SUCCESS) {
5008 /* Remote is ready, send confirm immediately
5009 * after logical link is ready
5010 */
5011 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
5012 } else {
5013 /* Both logical link and move success
5014 * are required to confirm
5015 */
5016 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_COMP;
5017 }
5018
5019 /* Placeholder - get hci_chan for logical link */
5020 if (!hchan) {
5021 /* Logical link not available */
5022 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5023 break;
5024 }
5025
5026 /* If the logical link is not yet connected, do not
5027 * send confirmation.
5028 */
5029 if (hchan->state != BT_CONNECTED)
5030 break;
5031
5032 /* Logical link is already ready to go */
5033
5034 chan->hs_hcon = hchan->conn;
5035 chan->hs_hcon->l2cap_data = chan->conn;
5036
5037 if (result == L2CAP_MR_SUCCESS) {
5038 /* Can confirm now */
5039 l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
5040 } else {
5041 /* Now only need move success
5042 * to confirm
5043 */
5044 chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
5045 }
5046
5047 l2cap_logical_cfm(chan, hchan, L2CAP_MR_SUCCESS);
5048 break;
5049 default:
5050 /* Any other amp move state means the move failed. */
5051 chan->move_id = chan->local_amp_id;
5052 l2cap_move_done(chan);
5053 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5054 }
5055
5056 l2cap_chan_unlock(chan);
5057}
5058
5059static void l2cap_move_fail(struct l2cap_conn *conn, u8 ident, u16 icid,
5060 u16 result)
5061{
5062 struct l2cap_chan *chan;
5063
5064 chan = l2cap_get_chan_by_ident(conn, ident);
5065 if (!chan) {
5066 /* Could not locate channel, icid is best guess */
5067 l2cap_send_move_chan_cfm_icid(conn, icid);
5068 return;
5069 }
5070
5071 __clear_chan_timer(chan);
5072
5073 if (chan->move_role == L2CAP_MOVE_ROLE_INITIATOR) {
5074 if (result == L2CAP_MR_COLLISION) {
5075 chan->move_role = L2CAP_MOVE_ROLE_RESPONDER;
5076 } else {
5077 /* Cleanup - cancel move */
5078 chan->move_id = chan->local_amp_id;
5079 l2cap_move_done(chan);
5080 }
5081 }
5082
5083 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5084
5085 l2cap_chan_unlock(chan);
5086}
5087
5088static int l2cap_move_channel_rsp(struct l2cap_conn *conn,
5089 struct l2cap_cmd_hdr *cmd,
5090 u16 cmd_len, void *data)
5091{
5092 struct l2cap_move_chan_rsp *rsp = data;
5093 u16 icid, result;
5094
5095 if (cmd_len != sizeof(*rsp))
5096 return -EPROTO;
5097
5098 icid = le16_to_cpu(rsp->icid);
5099 result = le16_to_cpu(rsp->result);
5100
5101 BT_DBG("icid 0x%4.4x, result 0x%4.4x", icid, result);
5102
5103 if (result == L2CAP_MR_SUCCESS || result == L2CAP_MR_PEND)
5104 l2cap_move_continue(conn, icid, result);
5105 else
5106 l2cap_move_fail(conn, cmd->ident, icid, result);
5107
5108 return 0;
5109}
5110
5111static int l2cap_move_channel_confirm(struct l2cap_conn *conn,
5112 struct l2cap_cmd_hdr *cmd,
5113 u16 cmd_len, void *data)
5114{
5115 struct l2cap_move_chan_cfm *cfm = data;
5116 struct l2cap_chan *chan;
5117 u16 icid, result;
5118
5119 if (cmd_len != sizeof(*cfm))
5120 return -EPROTO;
5121
5122 icid = le16_to_cpu(cfm->icid);
5123 result = le16_to_cpu(cfm->result);
5124
5125 BT_DBG("icid 0x%4.4x, result 0x%4.4x", icid, result);
5126
5127 chan = l2cap_get_chan_by_dcid(conn, icid);
5128 if (!chan) {
5129 /* Spec requires a response even if the icid was not found */
5130 l2cap_send_move_chan_cfm_rsp(conn, cmd->ident, icid);
5131 return 0;
5132 }
5133
5134 if (chan->move_state == L2CAP_MOVE_WAIT_CONFIRM) {
5135 if (result == L2CAP_MC_CONFIRMED) {
5136 chan->local_amp_id = chan->move_id;
5137 if (chan->local_amp_id == AMP_ID_BREDR)
5138 __release_logical_link(chan);
5139 } else {
5140 chan->move_id = chan->local_amp_id;
5141 }
5142
5143 l2cap_move_done(chan);
5144 }
5145
5146 l2cap_send_move_chan_cfm_rsp(conn, cmd->ident, icid);
5147
5148 l2cap_chan_unlock(chan);
5149
5150 return 0;
5151}
5152
5153static inline int l2cap_move_channel_confirm_rsp(struct l2cap_conn *conn,
5154 struct l2cap_cmd_hdr *cmd,
5155 u16 cmd_len, void *data)
5156{
5157 struct l2cap_move_chan_cfm_rsp *rsp = data;
5158 struct l2cap_chan *chan;
5159 u16 icid;
5160
5161 if (cmd_len != sizeof(*rsp))
5162 return -EPROTO;
5163
5164 icid = le16_to_cpu(rsp->icid);
5165
5166 BT_DBG("icid 0x%4.4x", icid);
5167
5168 chan = l2cap_get_chan_by_scid(conn, icid);
5169 if (!chan)
5170 return 0;
5171
5172 __clear_chan_timer(chan);
5173
5174 if (chan->move_state == L2CAP_MOVE_WAIT_CONFIRM_RSP) {
5175 chan->local_amp_id = chan->move_id;
5176
5177 if (chan->local_amp_id == AMP_ID_BREDR && chan->hs_hchan)
5178 __release_logical_link(chan);
5179
5180 l2cap_move_done(chan);
5181 }
5182
5183 l2cap_chan_unlock(chan);
5184
5185 return 0;
5186}
5187
5188static inline int l2cap_check_conn_param(u16 min, u16 max, u16 latency,
5189 u16 to_multiplier)
5190{
5191 u16 max_latency;
5192
5193 if (min > max || min < 6 || max > 3200)
5194 return -EINVAL;
5195
5196 if (to_multiplier < 10 || to_multiplier > 3200)
5197 return -EINVAL;
5198
5199 if (max >= to_multiplier * 8)
5200 return -EINVAL;
5201
5202 max_latency = (to_multiplier * 8 / max) - 1;
5203 if (latency > 499 || latency > max_latency)
5204 return -EINVAL;
5205
5206 return 0;
5207}
5208
5209static inline int l2cap_conn_param_update_req(struct l2cap_conn *conn,
5210 struct l2cap_cmd_hdr *cmd,
5211 u16 cmd_len, u8 *data)
5212{
5213 struct hci_conn *hcon = conn->hcon;
5214 struct l2cap_conn_param_update_req *req;
5215 struct l2cap_conn_param_update_rsp rsp;
5216 u16 min, max, latency, to_multiplier;
5217 int err;
5218
5219 if (!(hcon->link_mode & HCI_LM_MASTER))
5220 return -EINVAL;
5221
5222 if (cmd_len != sizeof(struct l2cap_conn_param_update_req))
5223 return -EPROTO;
5224
5225 req = (struct l2cap_conn_param_update_req *) data;
5226 min = __le16_to_cpu(req->min);
5227 max = __le16_to_cpu(req->max);
5228 latency = __le16_to_cpu(req->latency);
5229 to_multiplier = __le16_to_cpu(req->to_multiplier);
5230
5231 BT_DBG("min 0x%4.4x max 0x%4.4x latency: 0x%4.4x Timeout: 0x%4.4x",
5232 min, max, latency, to_multiplier);
5233
5234 memset(&rsp, 0, sizeof(rsp));
5235
5236 err = l2cap_check_conn_param(min, max, latency, to_multiplier);
5237 if (err)
5238 rsp.result = cpu_to_le16(L2CAP_CONN_PARAM_REJECTED);
5239 else
5240 rsp.result = cpu_to_le16(L2CAP_CONN_PARAM_ACCEPTED);
5241
5242 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONN_PARAM_UPDATE_RSP,
5243 sizeof(rsp), &rsp);
5244
5245 if (!err)
5246 hci_le_conn_update(hcon, min, max, latency, to_multiplier);
5247
5248 return 0;
5249}
5250
5251static int l2cap_le_connect_rsp(struct l2cap_conn *conn,
5252 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5253 u8 *data)
5254{
5255 struct l2cap_le_conn_rsp *rsp = (struct l2cap_le_conn_rsp *) data;
5256 u16 dcid, mtu, mps, credits, result;
5257 struct l2cap_chan *chan;
5258 int err;
5259
5260 if (cmd_len < sizeof(*rsp))
5261 return -EPROTO;
5262
5263 dcid = __le16_to_cpu(rsp->dcid);
5264 mtu = __le16_to_cpu(rsp->mtu);
5265 mps = __le16_to_cpu(rsp->mps);
5266 credits = __le16_to_cpu(rsp->credits);
5267 result = __le16_to_cpu(rsp->result);
5268
5269 if (result == L2CAP_CR_SUCCESS && (mtu < 23 || mps < 23))
5270 return -EPROTO;
5271
5272 BT_DBG("dcid 0x%4.4x mtu %u mps %u credits %u result 0x%2.2x",
5273 dcid, mtu, mps, credits, result);
5274
5275 mutex_lock(&conn->chan_lock);
5276
5277 chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
5278 if (!chan) {
5279 err = -EBADSLT;
5280 goto unlock;
5281 }
5282
5283 err = 0;
5284
5285 l2cap_chan_lock(chan);
5286
5287 switch (result) {
5288 case L2CAP_CR_SUCCESS:
5289 chan->ident = 0;
5290 chan->dcid = dcid;
5291 chan->omtu = mtu;
5292 chan->remote_mps = mps;
5293 chan->tx_credits = credits;
5294 l2cap_chan_ready(chan);
5295 break;
5296
5297 default:
5298 l2cap_chan_del(chan, ECONNREFUSED);
5299 break;
5300 }
5301
5302 l2cap_chan_unlock(chan);
5303
5304unlock:
5305 mutex_unlock(&conn->chan_lock);
5306
5307 return err;
5308}
5309
5310static inline int l2cap_bredr_sig_cmd(struct l2cap_conn *conn,
5311 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5312 u8 *data)
5313{
5314 int err = 0;
5315
5316 switch (cmd->code) {
5317 case L2CAP_COMMAND_REJ:
5318 l2cap_command_rej(conn, cmd, cmd_len, data);
5319 break;
5320
5321 case L2CAP_CONN_REQ:
5322 err = l2cap_connect_req(conn, cmd, cmd_len, data);
5323 break;
5324
5325 case L2CAP_CONN_RSP:
5326 case L2CAP_CREATE_CHAN_RSP:
5327 l2cap_connect_create_rsp(conn, cmd, cmd_len, data);
5328 break;
5329
5330 case L2CAP_CONF_REQ:
5331 err = l2cap_config_req(conn, cmd, cmd_len, data);
5332 break;
5333
5334 case L2CAP_CONF_RSP:
5335 l2cap_config_rsp(conn, cmd, cmd_len, data);
5336 break;
5337
5338 case L2CAP_DISCONN_REQ:
5339 err = l2cap_disconnect_req(conn, cmd, cmd_len, data);
5340 break;
5341
5342 case L2CAP_DISCONN_RSP:
5343 l2cap_disconnect_rsp(conn, cmd, cmd_len, data);
5344 break;
5345
5346 case L2CAP_ECHO_REQ:
5347 l2cap_send_cmd(conn, cmd->ident, L2CAP_ECHO_RSP, cmd_len, data);
5348 break;
5349
5350 case L2CAP_ECHO_RSP:
5351 break;
5352
5353 case L2CAP_INFO_REQ:
5354 err = l2cap_information_req(conn, cmd, cmd_len, data);
5355 break;
5356
5357 case L2CAP_INFO_RSP:
5358 l2cap_information_rsp(conn, cmd, cmd_len, data);
5359 break;
5360
5361 case L2CAP_CREATE_CHAN_REQ:
5362 err = l2cap_create_channel_req(conn, cmd, cmd_len, data);
5363 break;
5364
5365 case L2CAP_MOVE_CHAN_REQ:
5366 err = l2cap_move_channel_req(conn, cmd, cmd_len, data);
5367 break;
5368
5369 case L2CAP_MOVE_CHAN_RSP:
5370 l2cap_move_channel_rsp(conn, cmd, cmd_len, data);
5371 break;
5372
5373 case L2CAP_MOVE_CHAN_CFM:
5374 err = l2cap_move_channel_confirm(conn, cmd, cmd_len, data);
5375 break;
5376
5377 case L2CAP_MOVE_CHAN_CFM_RSP:
5378 l2cap_move_channel_confirm_rsp(conn, cmd, cmd_len, data);
5379 break;
5380
5381 default:
5382 BT_ERR("Unknown BR/EDR signaling command 0x%2.2x", cmd->code);
5383 err = -EINVAL;
5384 break;
5385 }
5386
5387 return err;
5388}
5389
5390static int l2cap_le_connect_req(struct l2cap_conn *conn,
5391 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5392 u8 *data)
5393{
5394 struct l2cap_le_conn_req *req = (struct l2cap_le_conn_req *) data;
5395 struct l2cap_le_conn_rsp rsp;
5396 struct l2cap_chan *chan, *pchan;
5397 u16 dcid, scid, credits, mtu, mps;
5398 __le16 psm;
5399 u8 result;
5400
5401 if (cmd_len != sizeof(*req))
5402 return -EPROTO;
5403
5404 scid = __le16_to_cpu(req->scid);
5405 mtu = __le16_to_cpu(req->mtu);
5406 mps = __le16_to_cpu(req->mps);
5407 psm = req->psm;
5408 dcid = 0;
5409 credits = 0;
5410
5411 if (mtu < 23 || mps < 23)
5412 return -EPROTO;
5413
5414 BT_DBG("psm 0x%2.2x scid 0x%4.4x mtu %u mps %u", __le16_to_cpu(psm),
5415 scid, mtu, mps);
5416
5417 /* Check if we have socket listening on psm */
5418 pchan = l2cap_global_chan_by_psm(BT_LISTEN, psm, &conn->hcon->src,
5419 &conn->hcon->dst, LE_LINK);
5420 if (!pchan) {
5421 result = L2CAP_CR_BAD_PSM;
5422 chan = NULL;
5423 goto response;
5424 }
5425
5426 mutex_lock(&conn->chan_lock);
5427 l2cap_chan_lock(pchan);
5428
5429 if (!smp_sufficient_security(conn->hcon, pchan->sec_level)) {
5430 result = L2CAP_CR_AUTHENTICATION;
5431 chan = NULL;
5432 goto response_unlock;
5433 }
5434
5435 /* Check if we already have channel with that dcid */
5436 if (__l2cap_get_chan_by_dcid(conn, scid)) {
5437 result = L2CAP_CR_NO_MEM;
5438 chan = NULL;
5439 goto response_unlock;
5440 }
5441
5442 chan = pchan->ops->new_connection(pchan);
5443 if (!chan) {
5444 result = L2CAP_CR_NO_MEM;
5445 goto response_unlock;
5446 }
5447
5448 l2cap_le_flowctl_init(chan);
5449
5450 bacpy(&chan->src, &conn->hcon->src);
5451 bacpy(&chan->dst, &conn->hcon->dst);
5452 chan->src_type = bdaddr_type(conn->hcon, conn->hcon->src_type);
5453 chan->dst_type = bdaddr_type(conn->hcon, conn->hcon->dst_type);
5454 chan->psm = psm;
5455 chan->dcid = scid;
5456 chan->omtu = mtu;
5457 chan->remote_mps = mps;
5458 chan->tx_credits = __le16_to_cpu(req->credits);
5459
5460 __l2cap_chan_add(conn, chan);
5461 dcid = chan->scid;
5462 credits = chan->rx_credits;
5463
5464 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
5465
5466 chan->ident = cmd->ident;
5467
5468 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
5469 l2cap_state_change(chan, BT_CONNECT2);
5470 result = L2CAP_CR_PEND;
5471 chan->ops->defer(chan);
5472 } else {
5473 l2cap_chan_ready(chan);
5474 result = L2CAP_CR_SUCCESS;
5475 }
5476
5477response_unlock:
5478 l2cap_chan_unlock(pchan);
5479 mutex_unlock(&conn->chan_lock);
5480
5481 if (result == L2CAP_CR_PEND)
5482 return 0;
5483
5484response:
5485 if (chan) {
5486 rsp.mtu = cpu_to_le16(chan->imtu);
5487 rsp.mps = cpu_to_le16(chan->mps);
5488 } else {
5489 rsp.mtu = 0;
5490 rsp.mps = 0;
5491 }
5492
5493 rsp.dcid = cpu_to_le16(dcid);
5494 rsp.credits = cpu_to_le16(credits);
5495 rsp.result = cpu_to_le16(result);
5496
5497 l2cap_send_cmd(conn, cmd->ident, L2CAP_LE_CONN_RSP, sizeof(rsp), &rsp);
5498
5499 return 0;
5500}
5501
5502static inline int l2cap_le_credits(struct l2cap_conn *conn,
5503 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5504 u8 *data)
5505{
5506 struct l2cap_le_credits *pkt;
5507 struct l2cap_chan *chan;
5508 u16 cid, credits, max_credits;
5509
5510 if (cmd_len != sizeof(*pkt))
5511 return -EPROTO;
5512
5513 pkt = (struct l2cap_le_credits *) data;
5514 cid = __le16_to_cpu(pkt->cid);
5515 credits = __le16_to_cpu(pkt->credits);
5516
5517 BT_DBG("cid 0x%4.4x credits 0x%4.4x", cid, credits);
5518
5519 chan = l2cap_get_chan_by_dcid(conn, cid);
5520 if (!chan)
5521 return -EBADSLT;
5522
5523 max_credits = LE_FLOWCTL_MAX_CREDITS - chan->tx_credits;
5524 if (credits > max_credits) {
5525 BT_ERR("LE credits overflow");
5526 l2cap_send_disconn_req(chan, ECONNRESET);
5527
5528 /* Return 0 so that we don't trigger an unnecessary
5529 * command reject packet.
5530 */
5531 return 0;
5532 }
5533
5534 chan->tx_credits += credits;
5535
5536 while (chan->tx_credits && !skb_queue_empty(&chan->tx_q)) {
5537 l2cap_do_send(chan, skb_dequeue(&chan->tx_q));
5538 chan->tx_credits--;
5539 }
5540
5541 if (chan->tx_credits)
5542 chan->ops->resume(chan);
5543
5544 l2cap_chan_unlock(chan);
5545
5546 return 0;
5547}
5548
5549static inline int l2cap_le_command_rej(struct l2cap_conn *conn,
5550 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5551 u8 *data)
5552{
5553 struct l2cap_cmd_rej_unk *rej = (struct l2cap_cmd_rej_unk *) data;
5554 struct l2cap_chan *chan;
5555
5556 if (cmd_len < sizeof(*rej))
5557 return -EPROTO;
5558
5559 mutex_lock(&conn->chan_lock);
5560
5561 chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
5562 if (!chan)
5563 goto done;
5564
5565 l2cap_chan_lock(chan);
5566 l2cap_chan_del(chan, ECONNREFUSED);
5567 l2cap_chan_unlock(chan);
5568
5569done:
5570 mutex_unlock(&conn->chan_lock);
5571 return 0;
5572}
5573
5574static inline int l2cap_le_sig_cmd(struct l2cap_conn *conn,
5575 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5576 u8 *data)
5577{
5578 int err = 0;
5579
5580 switch (cmd->code) {
5581 case L2CAP_COMMAND_REJ:
5582 l2cap_le_command_rej(conn, cmd, cmd_len, data);
5583 break;
5584
5585 case L2CAP_CONN_PARAM_UPDATE_REQ:
5586 err = l2cap_conn_param_update_req(conn, cmd, cmd_len, data);
5587 break;
5588
5589 case L2CAP_CONN_PARAM_UPDATE_RSP:
5590 break;
5591
5592 case L2CAP_LE_CONN_RSP:
5593 l2cap_le_connect_rsp(conn, cmd, cmd_len, data);
5594 break;
5595
5596 case L2CAP_LE_CONN_REQ:
5597 err = l2cap_le_connect_req(conn, cmd, cmd_len, data);
5598 break;
5599
5600 case L2CAP_LE_CREDITS:
5601 err = l2cap_le_credits(conn, cmd, cmd_len, data);
5602 break;
5603
5604 case L2CAP_DISCONN_REQ:
5605 err = l2cap_disconnect_req(conn, cmd, cmd_len, data);
5606 break;
5607
5608 case L2CAP_DISCONN_RSP:
5609 l2cap_disconnect_rsp(conn, cmd, cmd_len, data);
5610 break;
5611
5612 default:
5613 BT_ERR("Unknown LE signaling command 0x%2.2x", cmd->code);
5614 err = -EINVAL;
5615 break;
5616 }
5617
5618 return err;
5619}
5620
5621static inline void l2cap_le_sig_channel(struct l2cap_conn *conn,
5622 struct sk_buff *skb)
5623{
5624 struct hci_conn *hcon = conn->hcon;
5625 struct l2cap_cmd_hdr *cmd;
5626 u16 len;
5627 int err;
5628
5629 if (hcon->type != LE_LINK)
5630 goto drop;
5631
5632 if (skb->len < L2CAP_CMD_HDR_SIZE)
5633 goto drop;
5634
5635 cmd = (void *) skb->data;
5636 skb_pull(skb, L2CAP_CMD_HDR_SIZE);
5637
5638 len = le16_to_cpu(cmd->len);
5639
5640 BT_DBG("code 0x%2.2x len %d id 0x%2.2x", cmd->code, len, cmd->ident);
5641
5642 if (len != skb->len || !cmd->ident) {
5643 BT_DBG("corrupted command");
5644 goto drop;
5645 }
5646
5647 err = l2cap_le_sig_cmd(conn, cmd, len, skb->data);
5648 if (err) {
5649 struct l2cap_cmd_rej_unk rej;
5650
5651 BT_ERR("Wrong link type (%d)", err);
5652
5653 rej.reason = cpu_to_le16(L2CAP_REJ_NOT_UNDERSTOOD);
5654 l2cap_send_cmd(conn, cmd->ident, L2CAP_COMMAND_REJ,
5655 sizeof(rej), &rej);
5656 }
5657
5658drop:
5659 kfree_skb(skb);
5660}
5661
5662static inline void l2cap_sig_channel(struct l2cap_conn *conn,
5663 struct sk_buff *skb)
5664{
5665 struct hci_conn *hcon = conn->hcon;
5666 u8 *data = skb->data;
5667 int len = skb->len;
5668 struct l2cap_cmd_hdr cmd;
5669 int err;
5670
5671 l2cap_raw_recv(conn, skb);
5672
5673 if (hcon->type != ACL_LINK)
5674 goto drop;
5675
5676 while (len >= L2CAP_CMD_HDR_SIZE) {
5677 u16 cmd_len;
5678 memcpy(&cmd, data, L2CAP_CMD_HDR_SIZE);
5679 data += L2CAP_CMD_HDR_SIZE;
5680 len -= L2CAP_CMD_HDR_SIZE;
5681
5682 cmd_len = le16_to_cpu(cmd.len);
5683
5684 BT_DBG("code 0x%2.2x len %d id 0x%2.2x", cmd.code, cmd_len,
5685 cmd.ident);
5686
5687 if (cmd_len > len || !cmd.ident) {
5688 BT_DBG("corrupted command");
5689 break;
5690 }
5691
5692 err = l2cap_bredr_sig_cmd(conn, &cmd, cmd_len, data);
5693 if (err) {
5694 struct l2cap_cmd_rej_unk rej;
5695
5696 BT_ERR("Wrong link type (%d)", err);
5697
5698 rej.reason = cpu_to_le16(L2CAP_REJ_NOT_UNDERSTOOD);
5699 l2cap_send_cmd(conn, cmd.ident, L2CAP_COMMAND_REJ,
5700 sizeof(rej), &rej);
5701 }
5702
5703 data += cmd_len;
5704 len -= cmd_len;
5705 }
5706
5707drop:
5708 kfree_skb(skb);
5709}
5710
5711static int l2cap_check_fcs(struct l2cap_chan *chan, struct sk_buff *skb)
5712{
5713 u16 our_fcs, rcv_fcs;
5714 int hdr_size;
5715
5716 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
5717 hdr_size = L2CAP_EXT_HDR_SIZE;
5718 else
5719 hdr_size = L2CAP_ENH_HDR_SIZE;
5720
5721 if (chan->fcs == L2CAP_FCS_CRC16) {
5722 skb_trim(skb, skb->len - L2CAP_FCS_SIZE);
5723 rcv_fcs = get_unaligned_le16(skb->data + skb->len);
5724 our_fcs = crc16(0, skb->data - hdr_size, skb->len + hdr_size);
5725
5726 if (our_fcs != rcv_fcs)
5727 return -EBADMSG;
5728 }
5729 return 0;
5730}
5731
5732static void l2cap_send_i_or_rr_or_rnr(struct l2cap_chan *chan)
5733{
5734 struct l2cap_ctrl control;
5735
5736 BT_DBG("chan %p", chan);
5737
5738 memset(&control, 0, sizeof(control));
5739 control.sframe = 1;
5740 control.final = 1;
5741 control.reqseq = chan->buffer_seq;
5742 set_bit(CONN_SEND_FBIT, &chan->conn_state);
5743
5744 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
5745 control.super = L2CAP_SUPER_RNR;
5746 l2cap_send_sframe(chan, &control);
5747 }
5748
5749 if (test_and_clear_bit(CONN_REMOTE_BUSY, &chan->conn_state) &&
5750 chan->unacked_frames > 0)
5751 __set_retrans_timer(chan);
5752
5753 /* Send pending iframes */
5754 l2cap_ertm_send(chan);
5755
5756 if (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state) &&
5757 test_bit(CONN_SEND_FBIT, &chan->conn_state)) {
5758 /* F-bit wasn't sent in an s-frame or i-frame yet, so
5759 * send it now.
5760 */
5761 control.super = L2CAP_SUPER_RR;
5762 l2cap_send_sframe(chan, &control);
5763 }
5764}
5765
5766static void append_skb_frag(struct sk_buff *skb, struct sk_buff *new_frag,
5767 struct sk_buff **last_frag)
5768{
5769 /* skb->len reflects data in skb as well as all fragments
5770 * skb->data_len reflects only data in fragments
5771 */
5772 if (!skb_has_frag_list(skb))
5773 skb_shinfo(skb)->frag_list = new_frag;
5774
5775 new_frag->next = NULL;
5776
5777 (*last_frag)->next = new_frag;
5778 *last_frag = new_frag;
5779
5780 skb->len += new_frag->len;
5781 skb->data_len += new_frag->len;
5782 skb->truesize += new_frag->truesize;
5783}
5784
5785static int l2cap_reassemble_sdu(struct l2cap_chan *chan, struct sk_buff *skb,
5786 struct l2cap_ctrl *control)
5787{
5788 int err = -EINVAL;
5789
5790 switch (control->sar) {
5791 case L2CAP_SAR_UNSEGMENTED:
5792 if (chan->sdu)
5793 break;
5794
5795 err = chan->ops->recv(chan, skb);
5796 break;
5797
5798 case L2CAP_SAR_START:
5799 if (chan->sdu)
5800 break;
5801
5802 chan->sdu_len = get_unaligned_le16(skb->data);
5803 skb_pull(skb, L2CAP_SDULEN_SIZE);
5804
5805 if (chan->sdu_len > chan->imtu) {
5806 err = -EMSGSIZE;
5807 break;
5808 }
5809
5810 if (skb->len >= chan->sdu_len)
5811 break;
5812
5813 chan->sdu = skb;
5814 chan->sdu_last_frag = skb;
5815
5816 skb = NULL;
5817 err = 0;
5818 break;
5819
5820 case L2CAP_SAR_CONTINUE:
5821 if (!chan->sdu)
5822 break;
5823
5824 append_skb_frag(chan->sdu, skb,
5825 &chan->sdu_last_frag);
5826 skb = NULL;
5827
5828 if (chan->sdu->len >= chan->sdu_len)
5829 break;
5830
5831 err = 0;
5832 break;
5833
5834 case L2CAP_SAR_END:
5835 if (!chan->sdu)
5836 break;
5837
5838 append_skb_frag(chan->sdu, skb,
5839 &chan->sdu_last_frag);
5840 skb = NULL;
5841
5842 if (chan->sdu->len != chan->sdu_len)
5843 break;
5844
5845 err = chan->ops->recv(chan, chan->sdu);
5846
5847 if (!err) {
5848 /* Reassembly complete */
5849 chan->sdu = NULL;
5850 chan->sdu_last_frag = NULL;
5851 chan->sdu_len = 0;
5852 }
5853 break;
5854 }
5855
5856 if (err) {
5857 kfree_skb(skb);
5858 kfree_skb(chan->sdu);
5859 chan->sdu = NULL;
5860 chan->sdu_last_frag = NULL;
5861 chan->sdu_len = 0;
5862 }
5863
5864 return err;
5865}
5866
5867static int l2cap_resegment(struct l2cap_chan *chan)
5868{
5869 /* Placeholder */
5870 return 0;
5871}
5872
5873void l2cap_chan_busy(struct l2cap_chan *chan, int busy)
5874{
5875 u8 event;
5876
5877 if (chan->mode != L2CAP_MODE_ERTM)
5878 return;
5879
5880 event = busy ? L2CAP_EV_LOCAL_BUSY_DETECTED : L2CAP_EV_LOCAL_BUSY_CLEAR;
5881 l2cap_tx(chan, NULL, NULL, event);
5882}
5883
5884static int l2cap_rx_queued_iframes(struct l2cap_chan *chan)
5885{
5886 int err = 0;
5887 /* Pass sequential frames to l2cap_reassemble_sdu()
5888 * until a gap is encountered.
5889 */
5890
5891 BT_DBG("chan %p", chan);
5892
5893 while (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
5894 struct sk_buff *skb;
5895 BT_DBG("Searching for skb with txseq %d (queue len %d)",
5896 chan->buffer_seq, skb_queue_len(&chan->srej_q));
5897
5898 skb = l2cap_ertm_seq_in_queue(&chan->srej_q, chan->buffer_seq);
5899
5900 if (!skb)
5901 break;
5902
5903 skb_unlink(skb, &chan->srej_q);
5904 chan->buffer_seq = __next_seq(chan, chan->buffer_seq);
5905 err = l2cap_reassemble_sdu(chan, skb, &bt_cb(skb)->control);
5906 if (err)
5907 break;
5908 }
5909
5910 if (skb_queue_empty(&chan->srej_q)) {
5911 chan->rx_state = L2CAP_RX_STATE_RECV;
5912 l2cap_send_ack(chan);
5913 }
5914
5915 return err;
5916}
5917
5918static void l2cap_handle_srej(struct l2cap_chan *chan,
5919 struct l2cap_ctrl *control)
5920{
5921 struct sk_buff *skb;
5922
5923 BT_DBG("chan %p, control %p", chan, control);
5924
5925 if (control->reqseq == chan->next_tx_seq) {
5926 BT_DBG("Invalid reqseq %d, disconnecting", control->reqseq);
5927 l2cap_send_disconn_req(chan, ECONNRESET);
5928 return;
5929 }
5930
5931 skb = l2cap_ertm_seq_in_queue(&chan->tx_q, control->reqseq);
5932
5933 if (skb == NULL) {
5934 BT_DBG("Seq %d not available for retransmission",
5935 control->reqseq);
5936 return;
5937 }
5938
5939 if (chan->max_tx != 0 && bt_cb(skb)->control.retries >= chan->max_tx) {
5940 BT_DBG("Retry limit exceeded (%d)", chan->max_tx);
5941 l2cap_send_disconn_req(chan, ECONNRESET);
5942 return;
5943 }
5944
5945 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
5946
5947 if (control->poll) {
5948 l2cap_pass_to_tx(chan, control);
5949
5950 set_bit(CONN_SEND_FBIT, &chan->conn_state);
5951 l2cap_retransmit(chan, control);
5952 l2cap_ertm_send(chan);
5953
5954 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F) {
5955 set_bit(CONN_SREJ_ACT, &chan->conn_state);
5956 chan->srej_save_reqseq = control->reqseq;
5957 }
5958 } else {
5959 l2cap_pass_to_tx_fbit(chan, control);
5960
5961 if (control->final) {
5962 if (chan->srej_save_reqseq != control->reqseq ||
5963 !test_and_clear_bit(CONN_SREJ_ACT,
5964 &chan->conn_state))
5965 l2cap_retransmit(chan, control);
5966 } else {
5967 l2cap_retransmit(chan, control);
5968 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F) {
5969 set_bit(CONN_SREJ_ACT, &chan->conn_state);
5970 chan->srej_save_reqseq = control->reqseq;
5971 }
5972 }
5973 }
5974}
5975
5976static void l2cap_handle_rej(struct l2cap_chan *chan,
5977 struct l2cap_ctrl *control)
5978{
5979 struct sk_buff *skb;
5980
5981 BT_DBG("chan %p, control %p", chan, control);
5982
5983 if (control->reqseq == chan->next_tx_seq) {
5984 BT_DBG("Invalid reqseq %d, disconnecting", control->reqseq);
5985 l2cap_send_disconn_req(chan, ECONNRESET);
5986 return;
5987 }
5988
5989 skb = l2cap_ertm_seq_in_queue(&chan->tx_q, control->reqseq);
5990
5991 if (chan->max_tx && skb &&
5992 bt_cb(skb)->control.retries >= chan->max_tx) {
5993 BT_DBG("Retry limit exceeded (%d)", chan->max_tx);
5994 l2cap_send_disconn_req(chan, ECONNRESET);
5995 return;
5996 }
5997
5998 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
5999
6000 l2cap_pass_to_tx(chan, control);
6001
6002 if (control->final) {
6003 if (!test_and_clear_bit(CONN_REJ_ACT, &chan->conn_state))
6004 l2cap_retransmit_all(chan, control);
6005 } else {
6006 l2cap_retransmit_all(chan, control);
6007 l2cap_ertm_send(chan);
6008 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F)
6009 set_bit(CONN_REJ_ACT, &chan->conn_state);
6010 }
6011}
6012
6013static u8 l2cap_classify_txseq(struct l2cap_chan *chan, u16 txseq)
6014{
6015 BT_DBG("chan %p, txseq %d", chan, txseq);
6016
6017 BT_DBG("last_acked_seq %d, expected_tx_seq %d", chan->last_acked_seq,
6018 chan->expected_tx_seq);
6019
6020 if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) {
6021 if (__seq_offset(chan, txseq, chan->last_acked_seq) >=
6022 chan->tx_win) {
6023 /* See notes below regarding "double poll" and
6024 * invalid packets.
6025 */
6026 if (chan->tx_win <= ((chan->tx_win_max + 1) >> 1)) {
6027 BT_DBG("Invalid/Ignore - after SREJ");
6028 return L2CAP_TXSEQ_INVALID_IGNORE;
6029 } else {
6030 BT_DBG("Invalid - in window after SREJ sent");
6031 return L2CAP_TXSEQ_INVALID;
6032 }
6033 }
6034
6035 if (chan->srej_list.head == txseq) {
6036 BT_DBG("Expected SREJ");
6037 return L2CAP_TXSEQ_EXPECTED_SREJ;
6038 }
6039
6040 if (l2cap_ertm_seq_in_queue(&chan->srej_q, txseq)) {
6041 BT_DBG("Duplicate SREJ - txseq already stored");
6042 return L2CAP_TXSEQ_DUPLICATE_SREJ;
6043 }
6044
6045 if (l2cap_seq_list_contains(&chan->srej_list, txseq)) {
6046 BT_DBG("Unexpected SREJ - not requested");
6047 return L2CAP_TXSEQ_UNEXPECTED_SREJ;
6048 }
6049 }
6050
6051 if (chan->expected_tx_seq == txseq) {
6052 if (__seq_offset(chan, txseq, chan->last_acked_seq) >=
6053 chan->tx_win) {
6054 BT_DBG("Invalid - txseq outside tx window");
6055 return L2CAP_TXSEQ_INVALID;
6056 } else {
6057 BT_DBG("Expected");
6058 return L2CAP_TXSEQ_EXPECTED;
6059 }
6060 }
6061
6062 if (__seq_offset(chan, txseq, chan->last_acked_seq) <
6063 __seq_offset(chan, chan->expected_tx_seq, chan->last_acked_seq)) {
6064 BT_DBG("Duplicate - expected_tx_seq later than txseq");
6065 return L2CAP_TXSEQ_DUPLICATE;
6066 }
6067
6068 if (__seq_offset(chan, txseq, chan->last_acked_seq) >= chan->tx_win) {
6069 /* A source of invalid packets is a "double poll" condition,
6070 * where delays cause us to send multiple poll packets. If
6071 * the remote stack receives and processes both polls,
6072 * sequence numbers can wrap around in such a way that a
6073 * resent frame has a sequence number that looks like new data
6074 * with a sequence gap. This would trigger an erroneous SREJ
6075 * request.
6076 *
6077 * Fortunately, this is impossible with a tx window that's
6078 * less than half of the maximum sequence number, which allows
6079 * invalid frames to be safely ignored.
6080 *
6081 * With tx window sizes greater than half of the tx window
6082 * maximum, the frame is invalid and cannot be ignored. This
6083 * causes a disconnect.
6084 */
6085
6086 if (chan->tx_win <= ((chan->tx_win_max + 1) >> 1)) {
6087 BT_DBG("Invalid/Ignore - txseq outside tx window");
6088 return L2CAP_TXSEQ_INVALID_IGNORE;
6089 } else {
6090 BT_DBG("Invalid - txseq outside tx window");
6091 return L2CAP_TXSEQ_INVALID;
6092 }
6093 } else {
6094 BT_DBG("Unexpected - txseq indicates missing frames");
6095 return L2CAP_TXSEQ_UNEXPECTED;
6096 }
6097}
6098
6099static int l2cap_rx_state_recv(struct l2cap_chan *chan,
6100 struct l2cap_ctrl *control,
6101 struct sk_buff *skb, u8 event)
6102{
6103 int err = 0;
6104 bool skb_in_use = false;
6105
6106 BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
6107 event);
6108
6109 switch (event) {
6110 case L2CAP_EV_RECV_IFRAME:
6111 switch (l2cap_classify_txseq(chan, control->txseq)) {
6112 case L2CAP_TXSEQ_EXPECTED:
6113 l2cap_pass_to_tx(chan, control);
6114
6115 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
6116 BT_DBG("Busy, discarding expected seq %d",
6117 control->txseq);
6118 break;
6119 }
6120
6121 chan->expected_tx_seq = __next_seq(chan,
6122 control->txseq);
6123
6124 chan->buffer_seq = chan->expected_tx_seq;
6125 skb_in_use = true;
6126
6127 err = l2cap_reassemble_sdu(chan, skb, control);
6128 if (err)
6129 break;
6130
6131 if (control->final) {
6132 if (!test_and_clear_bit(CONN_REJ_ACT,
6133 &chan->conn_state)) {
6134 control->final = 0;
6135 l2cap_retransmit_all(chan, control);
6136 l2cap_ertm_send(chan);
6137 }
6138 }
6139
6140 if (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state))
6141 l2cap_send_ack(chan);
6142 break;
6143 case L2CAP_TXSEQ_UNEXPECTED:
6144 l2cap_pass_to_tx(chan, control);
6145
6146 /* Can't issue SREJ frames in the local busy state.
6147 * Drop this frame, it will be seen as missing
6148 * when local busy is exited.
6149 */
6150 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
6151 BT_DBG("Busy, discarding unexpected seq %d",
6152 control->txseq);
6153 break;
6154 }
6155
6156 /* There was a gap in the sequence, so an SREJ
6157 * must be sent for each missing frame. The
6158 * current frame is stored for later use.
6159 */
6160 skb_queue_tail(&chan->srej_q, skb);
6161 skb_in_use = true;
6162 BT_DBG("Queued %p (queue len %d)", skb,
6163 skb_queue_len(&chan->srej_q));
6164
6165 clear_bit(CONN_SREJ_ACT, &chan->conn_state);
6166 l2cap_seq_list_clear(&chan->srej_list);
6167 l2cap_send_srej(chan, control->txseq);
6168
6169 chan->rx_state = L2CAP_RX_STATE_SREJ_SENT;
6170 break;
6171 case L2CAP_TXSEQ_DUPLICATE:
6172 l2cap_pass_to_tx(chan, control);
6173 break;
6174 case L2CAP_TXSEQ_INVALID_IGNORE:
6175 break;
6176 case L2CAP_TXSEQ_INVALID:
6177 default:
6178 l2cap_send_disconn_req(chan, ECONNRESET);
6179 break;
6180 }
6181 break;
6182 case L2CAP_EV_RECV_RR:
6183 l2cap_pass_to_tx(chan, control);
6184 if (control->final) {
6185 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6186
6187 if (!test_and_clear_bit(CONN_REJ_ACT, &chan->conn_state) &&
6188 !__chan_is_moving(chan)) {
6189 control->final = 0;
6190 l2cap_retransmit_all(chan, control);
6191 }
6192
6193 l2cap_ertm_send(chan);
6194 } else if (control->poll) {
6195 l2cap_send_i_or_rr_or_rnr(chan);
6196 } else {
6197 if (test_and_clear_bit(CONN_REMOTE_BUSY,
6198 &chan->conn_state) &&
6199 chan->unacked_frames)
6200 __set_retrans_timer(chan);
6201
6202 l2cap_ertm_send(chan);
6203 }
6204 break;
6205 case L2CAP_EV_RECV_RNR:
6206 set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6207 l2cap_pass_to_tx(chan, control);
6208 if (control && control->poll) {
6209 set_bit(CONN_SEND_FBIT, &chan->conn_state);
6210 l2cap_send_rr_or_rnr(chan, 0);
6211 }
6212 __clear_retrans_timer(chan);
6213 l2cap_seq_list_clear(&chan->retrans_list);
6214 break;
6215 case L2CAP_EV_RECV_REJ:
6216 l2cap_handle_rej(chan, control);
6217 break;
6218 case L2CAP_EV_RECV_SREJ:
6219 l2cap_handle_srej(chan, control);
6220 break;
6221 default:
6222 break;
6223 }
6224
6225 if (skb && !skb_in_use) {
6226 BT_DBG("Freeing %p", skb);
6227 kfree_skb(skb);
6228 }
6229
6230 return err;
6231}
6232
6233static int l2cap_rx_state_srej_sent(struct l2cap_chan *chan,
6234 struct l2cap_ctrl *control,
6235 struct sk_buff *skb, u8 event)
6236{
6237 int err = 0;
6238 u16 txseq = control->txseq;
6239 bool skb_in_use = false;
6240
6241 BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
6242 event);
6243
6244 switch (event) {
6245 case L2CAP_EV_RECV_IFRAME:
6246 switch (l2cap_classify_txseq(chan, txseq)) {
6247 case L2CAP_TXSEQ_EXPECTED:
6248 /* Keep frame for reassembly later */
6249 l2cap_pass_to_tx(chan, control);
6250 skb_queue_tail(&chan->srej_q, skb);
6251 skb_in_use = true;
6252 BT_DBG("Queued %p (queue len %d)", skb,
6253 skb_queue_len(&chan->srej_q));
6254
6255 chan->expected_tx_seq = __next_seq(chan, txseq);
6256 break;
6257 case L2CAP_TXSEQ_EXPECTED_SREJ:
6258 l2cap_seq_list_pop(&chan->srej_list);
6259
6260 l2cap_pass_to_tx(chan, control);
6261 skb_queue_tail(&chan->srej_q, skb);
6262 skb_in_use = true;
6263 BT_DBG("Queued %p (queue len %d)", skb,
6264 skb_queue_len(&chan->srej_q));
6265
6266 err = l2cap_rx_queued_iframes(chan);
6267 if (err)
6268 break;
6269
6270 break;
6271 case L2CAP_TXSEQ_UNEXPECTED:
6272 /* Got a frame that can't be reassembled yet.
6273 * Save it for later, and send SREJs to cover
6274 * the missing frames.
6275 */
6276 skb_queue_tail(&chan->srej_q, skb);
6277 skb_in_use = true;
6278 BT_DBG("Queued %p (queue len %d)", skb,
6279 skb_queue_len(&chan->srej_q));
6280
6281 l2cap_pass_to_tx(chan, control);
6282 l2cap_send_srej(chan, control->txseq);
6283 break;
6284 case L2CAP_TXSEQ_UNEXPECTED_SREJ:
6285 /* This frame was requested with an SREJ, but
6286 * some expected retransmitted frames are
6287 * missing. Request retransmission of missing
6288 * SREJ'd frames.
6289 */
6290 skb_queue_tail(&chan->srej_q, skb);
6291 skb_in_use = true;
6292 BT_DBG("Queued %p (queue len %d)", skb,
6293 skb_queue_len(&chan->srej_q));
6294
6295 l2cap_pass_to_tx(chan, control);
6296 l2cap_send_srej_list(chan, control->txseq);
6297 break;
6298 case L2CAP_TXSEQ_DUPLICATE_SREJ:
6299 /* We've already queued this frame. Drop this copy. */
6300 l2cap_pass_to_tx(chan, control);
6301 break;
6302 case L2CAP_TXSEQ_DUPLICATE:
6303 /* Expecting a later sequence number, so this frame
6304 * was already received. Ignore it completely.
6305 */
6306 break;
6307 case L2CAP_TXSEQ_INVALID_IGNORE:
6308 break;
6309 case L2CAP_TXSEQ_INVALID:
6310 default:
6311 l2cap_send_disconn_req(chan, ECONNRESET);
6312 break;
6313 }
6314 break;
6315 case L2CAP_EV_RECV_RR:
6316 l2cap_pass_to_tx(chan, control);
6317 if (control->final) {
6318 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6319
6320 if (!test_and_clear_bit(CONN_REJ_ACT,
6321 &chan->conn_state)) {
6322 control->final = 0;
6323 l2cap_retransmit_all(chan, control);
6324 }
6325
6326 l2cap_ertm_send(chan);
6327 } else if (control->poll) {
6328 if (test_and_clear_bit(CONN_REMOTE_BUSY,
6329 &chan->conn_state) &&
6330 chan->unacked_frames) {
6331 __set_retrans_timer(chan);
6332 }
6333
6334 set_bit(CONN_SEND_FBIT, &chan->conn_state);
6335 l2cap_send_srej_tail(chan);
6336 } else {
6337 if (test_and_clear_bit(CONN_REMOTE_BUSY,
6338 &chan->conn_state) &&
6339 chan->unacked_frames)
6340 __set_retrans_timer(chan);
6341
6342 l2cap_send_ack(chan);
6343 }
6344 break;
6345 case L2CAP_EV_RECV_RNR:
6346 set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6347 l2cap_pass_to_tx(chan, control);
6348 if (control->poll) {
6349 l2cap_send_srej_tail(chan);
6350 } else {
6351 struct l2cap_ctrl rr_control;
6352 memset(&rr_control, 0, sizeof(rr_control));
6353 rr_control.sframe = 1;
6354 rr_control.super = L2CAP_SUPER_RR;
6355 rr_control.reqseq = chan->buffer_seq;
6356 l2cap_send_sframe(chan, &rr_control);
6357 }
6358
6359 break;
6360 case L2CAP_EV_RECV_REJ:
6361 l2cap_handle_rej(chan, control);
6362 break;
6363 case L2CAP_EV_RECV_SREJ:
6364 l2cap_handle_srej(chan, control);
6365 break;
6366 }
6367
6368 if (skb && !skb_in_use) {
6369 BT_DBG("Freeing %p", skb);
6370 kfree_skb(skb);
6371 }
6372
6373 return err;
6374}
6375
6376static int l2cap_finish_move(struct l2cap_chan *chan)
6377{
6378 BT_DBG("chan %p", chan);
6379
6380 chan->rx_state = L2CAP_RX_STATE_RECV;
6381
6382 if (chan->hs_hcon)
6383 chan->conn->mtu = chan->hs_hcon->hdev->block_mtu;
6384 else
6385 chan->conn->mtu = chan->conn->hcon->hdev->acl_mtu;
6386
6387 return l2cap_resegment(chan);
6388}
6389
6390static int l2cap_rx_state_wait_p(struct l2cap_chan *chan,
6391 struct l2cap_ctrl *control,
6392 struct sk_buff *skb, u8 event)
6393{
6394 int err;
6395
6396 BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
6397 event);
6398
6399 if (!control->poll)
6400 return -EPROTO;
6401
6402 l2cap_process_reqseq(chan, control->reqseq);
6403
6404 if (!skb_queue_empty(&chan->tx_q))
6405 chan->tx_send_head = skb_peek(&chan->tx_q);
6406 else
6407 chan->tx_send_head = NULL;
6408
6409 /* Rewind next_tx_seq to the point expected
6410 * by the receiver.
6411 */
6412 chan->next_tx_seq = control->reqseq;
6413 chan->unacked_frames = 0;
6414
6415 err = l2cap_finish_move(chan);
6416 if (err)
6417 return err;
6418
6419 set_bit(CONN_SEND_FBIT, &chan->conn_state);
6420 l2cap_send_i_or_rr_or_rnr(chan);
6421
6422 if (event == L2CAP_EV_RECV_IFRAME)
6423 return -EPROTO;
6424
6425 return l2cap_rx_state_recv(chan, control, NULL, event);
6426}
6427
6428static int l2cap_rx_state_wait_f(struct l2cap_chan *chan,
6429 struct l2cap_ctrl *control,
6430 struct sk_buff *skb, u8 event)
6431{
6432 int err;
6433
6434 if (!control->final)
6435 return -EPROTO;
6436
6437 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6438
6439 chan->rx_state = L2CAP_RX_STATE_RECV;
6440 l2cap_process_reqseq(chan, control->reqseq);
6441
6442 if (!skb_queue_empty(&chan->tx_q))
6443 chan->tx_send_head = skb_peek(&chan->tx_q);
6444 else
6445 chan->tx_send_head = NULL;
6446
6447 /* Rewind next_tx_seq to the point expected
6448 * by the receiver.
6449 */
6450 chan->next_tx_seq = control->reqseq;
6451 chan->unacked_frames = 0;
6452
6453 if (chan->hs_hcon)
6454 chan->conn->mtu = chan->hs_hcon->hdev->block_mtu;
6455 else
6456 chan->conn->mtu = chan->conn->hcon->hdev->acl_mtu;
6457
6458 err = l2cap_resegment(chan);
6459
6460 if (!err)
6461 err = l2cap_rx_state_recv(chan, control, skb, event);
6462
6463 return err;
6464}
6465
6466static bool __valid_reqseq(struct l2cap_chan *chan, u16 reqseq)
6467{
6468 /* Make sure reqseq is for a packet that has been sent but not acked */
6469 u16 unacked;
6470
6471 unacked = __seq_offset(chan, chan->next_tx_seq, chan->expected_ack_seq);
6472 return __seq_offset(chan, chan->next_tx_seq, reqseq) <= unacked;
6473}
6474
6475static int l2cap_rx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
6476 struct sk_buff *skb, u8 event)
6477{
6478 int err = 0;
6479
6480 BT_DBG("chan %p, control %p, skb %p, event %d, state %d", chan,
6481 control, skb, event, chan->rx_state);
6482
6483 if (__valid_reqseq(chan, control->reqseq)) {
6484 switch (chan->rx_state) {
6485 case L2CAP_RX_STATE_RECV:
6486 err = l2cap_rx_state_recv(chan, control, skb, event);
6487 break;
6488 case L2CAP_RX_STATE_SREJ_SENT:
6489 err = l2cap_rx_state_srej_sent(chan, control, skb,
6490 event);
6491 break;
6492 case L2CAP_RX_STATE_WAIT_P:
6493 err = l2cap_rx_state_wait_p(chan, control, skb, event);
6494 break;
6495 case L2CAP_RX_STATE_WAIT_F:
6496 err = l2cap_rx_state_wait_f(chan, control, skb, event);
6497 break;
6498 default:
6499 /* shut it down */
6500 break;
6501 }
6502 } else {
6503 BT_DBG("Invalid reqseq %d (next_tx_seq %d, expected_ack_seq %d",
6504 control->reqseq, chan->next_tx_seq,
6505 chan->expected_ack_seq);
6506 l2cap_send_disconn_req(chan, ECONNRESET);
6507 }
6508
6509 return err;
6510}
6511
6512static int l2cap_stream_rx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
6513 struct sk_buff *skb)
6514{
6515 int err = 0;
6516
6517 BT_DBG("chan %p, control %p, skb %p, state %d", chan, control, skb,
6518 chan->rx_state);
6519
6520 if (l2cap_classify_txseq(chan, control->txseq) ==
6521 L2CAP_TXSEQ_EXPECTED) {
6522 l2cap_pass_to_tx(chan, control);
6523
6524 BT_DBG("buffer_seq %d->%d", chan->buffer_seq,
6525 __next_seq(chan, chan->buffer_seq));
6526
6527 chan->buffer_seq = __next_seq(chan, chan->buffer_seq);
6528
6529 l2cap_reassemble_sdu(chan, skb, control);
6530 } else {
6531 if (chan->sdu) {
6532 kfree_skb(chan->sdu);
6533 chan->sdu = NULL;
6534 }
6535 chan->sdu_last_frag = NULL;
6536 chan->sdu_len = 0;
6537
6538 if (skb) {
6539 BT_DBG("Freeing %p", skb);
6540 kfree_skb(skb);
6541 }
6542 }
6543
6544 chan->last_acked_seq = control->txseq;
6545 chan->expected_tx_seq = __next_seq(chan, control->txseq);
6546
6547 return err;
6548}
6549
6550static int l2cap_data_rcv(struct l2cap_chan *chan, struct sk_buff *skb)
6551{
6552 struct l2cap_ctrl *control = &bt_cb(skb)->control;
6553 u16 len;
6554 u8 event;
6555
6556 __unpack_control(chan, skb);
6557
6558 len = skb->len;
6559
6560 /*
6561 * We can just drop the corrupted I-frame here.
6562 * Receiver will miss it and start proper recovery
6563 * procedures and ask for retransmission.
6564 */
6565 if (l2cap_check_fcs(chan, skb))
6566 goto drop;
6567
6568 if (!control->sframe && control->sar == L2CAP_SAR_START)
6569 len -= L2CAP_SDULEN_SIZE;
6570
6571 if (chan->fcs == L2CAP_FCS_CRC16)
6572 len -= L2CAP_FCS_SIZE;
6573
6574 if (len > chan->mps) {
6575 l2cap_send_disconn_req(chan, ECONNRESET);
6576 goto drop;
6577 }
6578
6579 if (!control->sframe) {
6580 int err;
6581
6582 BT_DBG("iframe sar %d, reqseq %d, final %d, txseq %d",
6583 control->sar, control->reqseq, control->final,
6584 control->txseq);
6585
6586 /* Validate F-bit - F=0 always valid, F=1 only
6587 * valid in TX WAIT_F
6588 */
6589 if (control->final && chan->tx_state != L2CAP_TX_STATE_WAIT_F)
6590 goto drop;
6591
6592 if (chan->mode != L2CAP_MODE_STREAMING) {
6593 event = L2CAP_EV_RECV_IFRAME;
6594 err = l2cap_rx(chan, control, skb, event);
6595 } else {
6596 err = l2cap_stream_rx(chan, control, skb);
6597 }
6598
6599 if (err)
6600 l2cap_send_disconn_req(chan, ECONNRESET);
6601 } else {
6602 const u8 rx_func_to_event[4] = {
6603 L2CAP_EV_RECV_RR, L2CAP_EV_RECV_REJ,
6604 L2CAP_EV_RECV_RNR, L2CAP_EV_RECV_SREJ
6605 };
6606
6607 /* Only I-frames are expected in streaming mode */
6608 if (chan->mode == L2CAP_MODE_STREAMING)
6609 goto drop;
6610
6611 BT_DBG("sframe reqseq %d, final %d, poll %d, super %d",
6612 control->reqseq, control->final, control->poll,
6613 control->super);
6614
6615 if (len != 0) {
6616 BT_ERR("Trailing bytes: %d in sframe", len);
6617 l2cap_send_disconn_req(chan, ECONNRESET);
6618 goto drop;
6619 }
6620
6621 /* Validate F and P bits */
6622 if (control->final && (control->poll ||
6623 chan->tx_state != L2CAP_TX_STATE_WAIT_F))
6624 goto drop;
6625
6626 event = rx_func_to_event[control->super];
6627 if (l2cap_rx(chan, control, skb, event))
6628 l2cap_send_disconn_req(chan, ECONNRESET);
6629 }
6630
6631 return 0;
6632
6633drop:
6634 kfree_skb(skb);
6635 return 0;
6636}
6637
6638static void l2cap_chan_le_send_credits(struct l2cap_chan *chan)
6639{
6640 struct l2cap_conn *conn = chan->conn;
6641 struct l2cap_le_credits pkt;
6642 u16 return_credits;
6643
6644 /* We return more credits to the sender only after the amount of
6645 * credits falls below half of the initial amount.
6646 */
6647 if (chan->rx_credits >= (le_max_credits + 1) / 2)
6648 return;
6649
6650 return_credits = le_max_credits - chan->rx_credits;
6651
6652 BT_DBG("chan %p returning %u credits to sender", chan, return_credits);
6653
6654 chan->rx_credits += return_credits;
6655
6656 pkt.cid = cpu_to_le16(chan->scid);
6657 pkt.credits = cpu_to_le16(return_credits);
6658
6659 chan->ident = l2cap_get_ident(conn);
6660
6661 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CREDITS, sizeof(pkt), &pkt);
6662}
6663
6664static int l2cap_le_data_rcv(struct l2cap_chan *chan, struct sk_buff *skb)
6665{
6666 int err;
6667
6668 if (!chan->rx_credits) {
6669 BT_ERR("No credits to receive LE L2CAP data");
6670 l2cap_send_disconn_req(chan, ECONNRESET);
6671 return -ENOBUFS;
6672 }
6673
6674 if (chan->imtu < skb->len) {
6675 BT_ERR("Too big LE L2CAP PDU");
6676 return -ENOBUFS;
6677 }
6678
6679 chan->rx_credits--;
6680 BT_DBG("rx_credits %u -> %u", chan->rx_credits + 1, chan->rx_credits);
6681
6682 l2cap_chan_le_send_credits(chan);
6683
6684 err = 0;
6685
6686 if (!chan->sdu) {
6687 u16 sdu_len;
6688
6689 sdu_len = get_unaligned_le16(skb->data);
6690 skb_pull(skb, L2CAP_SDULEN_SIZE);
6691
6692 BT_DBG("Start of new SDU. sdu_len %u skb->len %u imtu %u",
6693 sdu_len, skb->len, chan->imtu);
6694
6695 if (sdu_len > chan->imtu) {
6696 BT_ERR("Too big LE L2CAP SDU length received");
6697 err = -EMSGSIZE;
6698 goto failed;
6699 }
6700
6701 if (skb->len > sdu_len) {
6702 BT_ERR("Too much LE L2CAP data received");
6703 err = -EINVAL;
6704 goto failed;
6705 }
6706
6707 if (skb->len == sdu_len)
6708 return chan->ops->recv(chan, skb);
6709
6710 chan->sdu = skb;
6711 chan->sdu_len = sdu_len;
6712 chan->sdu_last_frag = skb;
6713
6714 return 0;
6715 }
6716
6717 BT_DBG("SDU fragment. chan->sdu->len %u skb->len %u chan->sdu_len %u",
6718 chan->sdu->len, skb->len, chan->sdu_len);
6719
6720 if (chan->sdu->len + skb->len > chan->sdu_len) {
6721 BT_ERR("Too much LE L2CAP data received");
6722 err = -EINVAL;
6723 goto failed;
6724 }
6725
6726 append_skb_frag(chan->sdu, skb, &chan->sdu_last_frag);
6727 skb = NULL;
6728
6729 if (chan->sdu->len == chan->sdu_len) {
6730 err = chan->ops->recv(chan, chan->sdu);
6731 if (!err) {
6732 chan->sdu = NULL;
6733 chan->sdu_last_frag = NULL;
6734 chan->sdu_len = 0;
6735 }
6736 }
6737
6738failed:
6739 if (err) {
6740 kfree_skb(skb);
6741 kfree_skb(chan->sdu);
6742 chan->sdu = NULL;
6743 chan->sdu_last_frag = NULL;
6744 chan->sdu_len = 0;
6745 }
6746
6747 /* We can't return an error here since we took care of the skb
6748 * freeing internally. An error return would cause the caller to
6749 * do a double-free of the skb.
6750 */
6751 return 0;
6752}
6753
6754static void l2cap_data_channel(struct l2cap_conn *conn, u16 cid,
6755 struct sk_buff *skb)
6756{
6757 struct l2cap_chan *chan;
6758
6759 chan = l2cap_get_chan_by_scid(conn, cid);
6760 if (!chan) {
6761 if (cid == L2CAP_CID_A2MP) {
6762 chan = a2mp_channel_create(conn, skb);
6763 if (!chan) {
6764 kfree_skb(skb);
6765 return;
6766 }
6767
6768 l2cap_chan_lock(chan);
6769 } else {
6770 BT_DBG("unknown cid 0x%4.4x", cid);
6771 /* Drop packet and return */
6772 kfree_skb(skb);
6773 return;
6774 }
6775 }
6776
6777 BT_DBG("chan %p, len %d", chan, skb->len);
6778
6779 if (chan->state != BT_CONNECTED)
6780 goto drop;
6781
6782 switch (chan->mode) {
6783 case L2CAP_MODE_LE_FLOWCTL:
6784 if (l2cap_le_data_rcv(chan, skb) < 0)
6785 goto drop;
6786
6787 goto done;
6788
6789 case L2CAP_MODE_BASIC:
6790 /* If socket recv buffers overflows we drop data here
6791 * which is *bad* because L2CAP has to be reliable.
6792 * But we don't have any other choice. L2CAP doesn't
6793 * provide flow control mechanism. */
6794
6795 if (chan->imtu < skb->len) {
6796 BT_ERR("Dropping L2CAP data: receive buffer overflow");
6797 goto drop;
6798 }
6799
6800 if (!chan->ops->recv(chan, skb))
6801 goto done;
6802 break;
6803
6804 case L2CAP_MODE_ERTM:
6805 case L2CAP_MODE_STREAMING:
6806 l2cap_data_rcv(chan, skb);
6807 goto done;
6808
6809 default:
6810 BT_DBG("chan %p: bad mode 0x%2.2x", chan, chan->mode);
6811 break;
6812 }
6813
6814drop:
6815 kfree_skb(skb);
6816
6817done:
6818 l2cap_chan_unlock(chan);
6819}
6820
6821static void l2cap_conless_channel(struct l2cap_conn *conn, __le16 psm,
6822 struct sk_buff *skb)
6823{
6824 struct hci_conn *hcon = conn->hcon;
6825 struct l2cap_chan *chan;
6826
6827 if (hcon->type != ACL_LINK)
6828 goto drop;
6829
6830 chan = l2cap_global_chan_by_psm(0, psm, &hcon->src, &hcon->dst,
6831 ACL_LINK);
6832 if (!chan)
6833 goto drop;
6834
6835 BT_DBG("chan %p, len %d", chan, skb->len);
6836
6837 if (chan->state != BT_BOUND && chan->state != BT_CONNECTED)
6838 goto drop;
6839
6840 if (chan->imtu < skb->len)
6841 goto drop;
6842
6843 /* Store remote BD_ADDR and PSM for msg_name */
6844 bacpy(&bt_cb(skb)->bdaddr, &hcon->dst);
6845 bt_cb(skb)->psm = psm;
6846
6847 if (!chan->ops->recv(chan, skb))
6848 return;
6849
6850drop:
6851 kfree_skb(skb);
6852}
6853
6854static void l2cap_att_channel(struct l2cap_conn *conn,
6855 struct sk_buff *skb)
6856{
6857 struct hci_conn *hcon = conn->hcon;
6858 struct l2cap_chan *chan;
6859
6860 if (hcon->type != LE_LINK)
6861 goto drop;
6862
6863 chan = l2cap_global_chan_by_scid(BT_CONNECTED, L2CAP_CID_ATT,
6864 &hcon->src, &hcon->dst);
6865 if (!chan)
6866 goto drop;
6867
6868 BT_DBG("chan %p, len %d", chan, skb->len);
6869
6870 if (hci_blacklist_lookup(hcon->hdev, &hcon->dst, hcon->dst_type))
6871 goto drop;
6872
6873 if (chan->imtu < skb->len)
6874 goto drop;
6875
6876 if (!chan->ops->recv(chan, skb))
6877 return;
6878
6879drop:
6880 kfree_skb(skb);
6881}
6882
6883static void l2cap_recv_frame(struct l2cap_conn *conn, struct sk_buff *skb)
6884{
6885 struct l2cap_hdr *lh = (void *) skb->data;
6886 struct hci_conn *hcon = conn->hcon;
6887 u16 cid, len;
6888 __le16 psm;
6889
6890 if (hcon->state != BT_CONNECTED) {
6891 BT_DBG("queueing pending rx skb");
6892 skb_queue_tail(&conn->pending_rx, skb);
6893 return;
6894 }
6895
6896 skb_pull(skb, L2CAP_HDR_SIZE);
6897 cid = __le16_to_cpu(lh->cid);
6898 len = __le16_to_cpu(lh->len);
6899
6900 if (len != skb->len) {
6901 kfree_skb(skb);
6902 return;
6903 }
6904
6905 BT_DBG("len %d, cid 0x%4.4x", len, cid);
6906
6907 switch (cid) {
6908 case L2CAP_CID_SIGNALING:
6909 l2cap_sig_channel(conn, skb);
6910 break;
6911
6912 case L2CAP_CID_CONN_LESS:
6913 psm = get_unaligned((__le16 *) skb->data);
6914 skb_pull(skb, L2CAP_PSMLEN_SIZE);
6915 l2cap_conless_channel(conn, psm, skb);
6916 break;
6917
6918 case L2CAP_CID_ATT:
6919 l2cap_att_channel(conn, skb);
6920 break;
6921
6922 case L2CAP_CID_LE_SIGNALING:
6923 l2cap_le_sig_channel(conn, skb);
6924 break;
6925
6926 case L2CAP_CID_SMP:
6927 if (smp_sig_channel(conn, skb))
6928 l2cap_conn_del(conn->hcon, EACCES);
6929 break;
6930
6931 case L2CAP_FC_6LOWPAN:
6932 bt_6lowpan_recv(conn, skb);
6933 break;
6934
6935 default:
6936 l2cap_data_channel(conn, cid, skb);
6937 break;
6938 }
6939}
6940
6941static void process_pending_rx(struct work_struct *work)
6942{
6943 struct l2cap_conn *conn = container_of(work, struct l2cap_conn,
6944 pending_rx_work);
6945 struct sk_buff *skb;
6946
6947 BT_DBG("");
6948
6949 while ((skb = skb_dequeue(&conn->pending_rx)))
6950 l2cap_recv_frame(conn, skb);
6951}
6952
6953static struct l2cap_conn *l2cap_conn_add(struct hci_conn *hcon)
6954{
6955 struct l2cap_conn *conn = hcon->l2cap_data;
6956 struct hci_chan *hchan;
6957
6958 if (conn)
6959 return conn;
6960
6961 hchan = hci_chan_create(hcon);
6962 if (!hchan)
6963 return NULL;
6964
6965 conn = kzalloc(sizeof(struct l2cap_conn), GFP_KERNEL);
6966 if (!conn) {
6967 hci_chan_del(hchan);
6968 return NULL;
6969 }
6970
6971 kref_init(&conn->ref);
6972 hcon->l2cap_data = conn;
6973 conn->hcon = hcon;
6974 hci_conn_get(conn->hcon);
6975 conn->hchan = hchan;
6976
6977 BT_DBG("hcon %p conn %p hchan %p", hcon, conn, hchan);
6978
6979 switch (hcon->type) {
6980 case LE_LINK:
6981 if (hcon->hdev->le_mtu) {
6982 conn->mtu = hcon->hdev->le_mtu;
6983 break;
6984 }
6985 /* fall through */
6986 default:
6987 conn->mtu = hcon->hdev->acl_mtu;
6988 break;
6989 }
6990
6991 conn->feat_mask = 0;
6992
6993 if (hcon->type == ACL_LINK)
6994 conn->hs_enabled = test_bit(HCI_HS_ENABLED,
6995 &hcon->hdev->dev_flags);
6996
6997 spin_lock_init(&conn->lock);
6998 mutex_init(&conn->chan_lock);
6999
7000 INIT_LIST_HEAD(&conn->chan_l);
7001 INIT_LIST_HEAD(&conn->users);
7002
7003 if (hcon->type == LE_LINK)
7004 INIT_DELAYED_WORK(&conn->security_timer, security_timeout);
7005 else
7006 INIT_DELAYED_WORK(&conn->info_timer, l2cap_info_timeout);
7007
7008 skb_queue_head_init(&conn->pending_rx);
7009 INIT_WORK(&conn->pending_rx_work, process_pending_rx);
7010
7011 conn->disc_reason = HCI_ERROR_REMOTE_USER_TERM;
7012
7013 return conn;
7014}
7015
7016static bool is_valid_psm(u16 psm, u8 dst_type) {
7017 if (!psm)
7018 return false;
7019
7020 if (bdaddr_type_is_le(dst_type))
7021 return (psm <= 0x00ff);
7022
7023 /* PSM must be odd and lsb of upper byte must be 0 */
7024 return ((psm & 0x0101) == 0x0001);
7025}
7026
7027int l2cap_chan_connect(struct l2cap_chan *chan, __le16 psm, u16 cid,
7028 bdaddr_t *dst, u8 dst_type)
7029{
7030 struct l2cap_conn *conn;
7031 struct hci_conn *hcon;
7032 struct hci_dev *hdev;
7033 __u8 auth_type;
7034 int err;
7035
7036 BT_DBG("%pMR -> %pMR (type %u) psm 0x%2.2x", &chan->src, dst,
7037 dst_type, __le16_to_cpu(psm));
7038
7039 hdev = hci_get_route(dst, &chan->src);
7040 if (!hdev)
7041 return -EHOSTUNREACH;
7042
7043 hci_dev_lock(hdev);
7044
7045 l2cap_chan_lock(chan);
7046
7047 if (!is_valid_psm(__le16_to_cpu(psm), dst_type) && !cid &&
7048 chan->chan_type != L2CAP_CHAN_RAW) {
7049 err = -EINVAL;
7050 goto done;
7051 }
7052
7053 if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED && !psm) {
7054 err = -EINVAL;
7055 goto done;
7056 }
7057
7058 if (chan->chan_type == L2CAP_CHAN_FIXED && !cid) {
7059 err = -EINVAL;
7060 goto done;
7061 }
7062
7063 switch (chan->mode) {
7064 case L2CAP_MODE_BASIC:
7065 break;
7066 case L2CAP_MODE_LE_FLOWCTL:
7067 l2cap_le_flowctl_init(chan);
7068 break;
7069 case L2CAP_MODE_ERTM:
7070 case L2CAP_MODE_STREAMING:
7071 if (!disable_ertm)
7072 break;
7073 /* fall through */
7074 default:
7075 err = -ENOTSUPP;
7076 goto done;
7077 }
7078
7079 switch (chan->state) {
7080 case BT_CONNECT:
7081 case BT_CONNECT2:
7082 case BT_CONFIG:
7083 /* Already connecting */
7084 err = 0;
7085 goto done;
7086
7087 case BT_CONNECTED:
7088 /* Already connected */
7089 err = -EISCONN;
7090 goto done;
7091
7092 case BT_OPEN:
7093 case BT_BOUND:
7094 /* Can connect */
7095 break;
7096
7097 default:
7098 err = -EBADFD;
7099 goto done;
7100 }
7101
7102 /* Set destination address and psm */
7103 bacpy(&chan->dst, dst);
7104 chan->dst_type = dst_type;
7105
7106 chan->psm = psm;
7107 chan->dcid = cid;
7108
7109 auth_type = l2cap_get_auth_type(chan);
7110
7111 if (bdaddr_type_is_le(dst_type)) {
7112 /* Convert from L2CAP channel address type to HCI address type
7113 */
7114 if (dst_type == BDADDR_LE_PUBLIC)
7115 dst_type = ADDR_LE_DEV_PUBLIC;
7116 else
7117 dst_type = ADDR_LE_DEV_RANDOM;
7118
7119 hcon = hci_connect_le(hdev, dst, dst_type, chan->sec_level,
7120 auth_type);
7121 } else {
7122 hcon = hci_connect_acl(hdev, dst, chan->sec_level, auth_type);
7123 }
7124
7125 if (IS_ERR(hcon)) {
7126 err = PTR_ERR(hcon);
7127 goto done;
7128 }
7129
7130 conn = l2cap_conn_add(hcon);
7131 if (!conn) {
7132 hci_conn_drop(hcon);
7133 err = -ENOMEM;
7134 goto done;
7135 }
7136
7137 if (cid && __l2cap_get_chan_by_dcid(conn, cid)) {
7138 hci_conn_drop(hcon);
7139 err = -EBUSY;
7140 goto done;
7141 }
7142
7143 /* Update source addr of the socket */
7144 bacpy(&chan->src, &hcon->src);
7145 chan->src_type = bdaddr_type(hcon, hcon->src_type);
7146
7147 l2cap_chan_unlock(chan);
7148 l2cap_chan_add(conn, chan);
7149 l2cap_chan_lock(chan);
7150
7151 /* l2cap_chan_add takes its own ref so we can drop this one */
7152 hci_conn_drop(hcon);
7153
7154 l2cap_state_change(chan, BT_CONNECT);
7155 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
7156
7157 /* Release chan->sport so that it can be reused by other
7158 * sockets (as it's only used for listening sockets).
7159 */
7160 write_lock(&chan_list_lock);
7161 chan->sport = 0;
7162 write_unlock(&chan_list_lock);
7163
7164 if (hcon->state == BT_CONNECTED) {
7165 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
7166 __clear_chan_timer(chan);
7167 if (l2cap_chan_check_security(chan))
7168 l2cap_state_change(chan, BT_CONNECTED);
7169 } else
7170 l2cap_do_start(chan);
7171 }
7172
7173 err = 0;
7174
7175done:
7176 l2cap_chan_unlock(chan);
7177 hci_dev_unlock(hdev);
7178 hci_dev_put(hdev);
7179 return err;
7180}
7181
7182/* ---- L2CAP interface with lower layer (HCI) ---- */
7183
7184int l2cap_connect_ind(struct hci_dev *hdev, bdaddr_t *bdaddr)
7185{
7186 int exact = 0, lm1 = 0, lm2 = 0;
7187 struct l2cap_chan *c;
7188
7189 BT_DBG("hdev %s, bdaddr %pMR", hdev->name, bdaddr);
7190
7191 /* Find listening sockets and check their link_mode */
7192 read_lock(&chan_list_lock);
7193 list_for_each_entry(c, &chan_list, global_l) {
7194 if (c->state != BT_LISTEN)
7195 continue;
7196
7197 if (!bacmp(&c->src, &hdev->bdaddr)) {
7198 lm1 |= HCI_LM_ACCEPT;
7199 if (test_bit(FLAG_ROLE_SWITCH, &c->flags))
7200 lm1 |= HCI_LM_MASTER;
7201 exact++;
7202 } else if (!bacmp(&c->src, BDADDR_ANY)) {
7203 lm2 |= HCI_LM_ACCEPT;
7204 if (test_bit(FLAG_ROLE_SWITCH, &c->flags))
7205 lm2 |= HCI_LM_MASTER;
7206 }
7207 }
7208 read_unlock(&chan_list_lock);
7209
7210 return exact ? lm1 : lm2;
7211}
7212
7213void l2cap_connect_cfm(struct hci_conn *hcon, u8 status)
7214{
7215 struct l2cap_conn *conn;
7216
7217 BT_DBG("hcon %p bdaddr %pMR status %d", hcon, &hcon->dst, status);
7218
7219 if (!status) {
7220 conn = l2cap_conn_add(hcon);
7221 if (conn)
7222 l2cap_conn_ready(conn);
7223 } else {
7224 l2cap_conn_del(hcon, bt_to_errno(status));
7225 }
7226}
7227
7228int l2cap_disconn_ind(struct hci_conn *hcon)
7229{
7230 struct l2cap_conn *conn = hcon->l2cap_data;
7231
7232 BT_DBG("hcon %p", hcon);
7233
7234 if (!conn)
7235 return HCI_ERROR_REMOTE_USER_TERM;
7236 return conn->disc_reason;
7237}
7238
7239void l2cap_disconn_cfm(struct hci_conn *hcon, u8 reason)
7240{
7241 BT_DBG("hcon %p reason %d", hcon, reason);
7242
7243 bt_6lowpan_del_conn(hcon->l2cap_data);
7244
7245 l2cap_conn_del(hcon, bt_to_errno(reason));
7246}
7247
7248static inline void l2cap_check_encryption(struct l2cap_chan *chan, u8 encrypt)
7249{
7250 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED)
7251 return;
7252
7253 if (encrypt == 0x00) {
7254 if (chan->sec_level == BT_SECURITY_MEDIUM) {
7255 __set_chan_timer(chan, L2CAP_ENC_TIMEOUT);
7256 } else if (chan->sec_level == BT_SECURITY_HIGH ||
7257 chan->sec_level == BT_SECURITY_FIPS)
7258 l2cap_chan_close(chan, ECONNREFUSED);
7259 } else {
7260 if (chan->sec_level == BT_SECURITY_MEDIUM)
7261 __clear_chan_timer(chan);
7262 }
7263}
7264
7265int l2cap_security_cfm(struct hci_conn *hcon, u8 status, u8 encrypt)
7266{
7267 struct l2cap_conn *conn = hcon->l2cap_data;
7268 struct l2cap_chan *chan;
7269
7270 if (!conn)
7271 return 0;
7272
7273 BT_DBG("conn %p status 0x%2.2x encrypt %u", conn, status, encrypt);
7274
7275 if (hcon->type == LE_LINK) {
7276 if (!status && encrypt)
7277 smp_distribute_keys(conn);
7278 cancel_delayed_work(&conn->security_timer);
7279 }
7280
7281 mutex_lock(&conn->chan_lock);
7282
7283 list_for_each_entry(chan, &conn->chan_l, list) {
7284 l2cap_chan_lock(chan);
7285
7286 BT_DBG("chan %p scid 0x%4.4x state %s", chan, chan->scid,
7287 state_to_string(chan->state));
7288
7289 if (chan->scid == L2CAP_CID_A2MP) {
7290 l2cap_chan_unlock(chan);
7291 continue;
7292 }
7293
7294 if (chan->scid == L2CAP_CID_ATT) {
7295 if (!status && encrypt) {
7296 chan->sec_level = hcon->sec_level;
7297 l2cap_chan_ready(chan);
7298 }
7299
7300 l2cap_chan_unlock(chan);
7301 continue;
7302 }
7303
7304 if (!__l2cap_no_conn_pending(chan)) {
7305 l2cap_chan_unlock(chan);
7306 continue;
7307 }
7308
7309 if (!status && (chan->state == BT_CONNECTED ||
7310 chan->state == BT_CONFIG)) {
7311 chan->ops->resume(chan);
7312 l2cap_check_encryption(chan, encrypt);
7313 l2cap_chan_unlock(chan);
7314 continue;
7315 }
7316
7317 if (chan->state == BT_CONNECT) {
7318 if (!status)
7319 l2cap_start_connection(chan);
7320 else
7321 __set_chan_timer(chan, L2CAP_DISC_TIMEOUT);
7322 } else if (chan->state == BT_CONNECT2) {
7323 struct l2cap_conn_rsp rsp;
7324 __u16 res, stat;
7325
7326 if (!status) {
7327 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
7328 res = L2CAP_CR_PEND;
7329 stat = L2CAP_CS_AUTHOR_PEND;
7330 chan->ops->defer(chan);
7331 } else {
7332 l2cap_state_change(chan, BT_CONFIG);
7333 res = L2CAP_CR_SUCCESS;
7334 stat = L2CAP_CS_NO_INFO;
7335 }
7336 } else {
7337 l2cap_state_change(chan, BT_DISCONN);
7338 __set_chan_timer(chan, L2CAP_DISC_TIMEOUT);
7339 res = L2CAP_CR_SEC_BLOCK;
7340 stat = L2CAP_CS_NO_INFO;
7341 }
7342
7343 rsp.scid = cpu_to_le16(chan->dcid);
7344 rsp.dcid = cpu_to_le16(chan->scid);
7345 rsp.result = cpu_to_le16(res);
7346 rsp.status = cpu_to_le16(stat);
7347 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP,
7348 sizeof(rsp), &rsp);
7349
7350 if (!test_bit(CONF_REQ_SENT, &chan->conf_state) &&
7351 res == L2CAP_CR_SUCCESS) {
7352 char buf[128];
7353 set_bit(CONF_REQ_SENT, &chan->conf_state);
7354 l2cap_send_cmd(conn, l2cap_get_ident(conn),
7355 L2CAP_CONF_REQ,
7356 l2cap_build_conf_req(chan, buf),
7357 buf);
7358 chan->num_conf_req++;
7359 }
7360 }
7361
7362 l2cap_chan_unlock(chan);
7363 }
7364
7365 mutex_unlock(&conn->chan_lock);
7366
7367 return 0;
7368}
7369
7370int l2cap_recv_acldata(struct hci_conn *hcon, struct sk_buff *skb, u16 flags)
7371{
7372 struct l2cap_conn *conn = hcon->l2cap_data;
7373 struct l2cap_hdr *hdr;
7374 int len;
7375
7376 /* For AMP controller do not create l2cap conn */
7377 if (!conn && hcon->hdev->dev_type != HCI_BREDR)
7378 goto drop;
7379
7380 if (!conn)
7381 conn = l2cap_conn_add(hcon);
7382
7383 if (!conn)
7384 goto drop;
7385
7386 BT_DBG("conn %p len %d flags 0x%x", conn, skb->len, flags);
7387
7388 switch (flags) {
7389 case ACL_START:
7390 case ACL_START_NO_FLUSH:
7391 case ACL_COMPLETE:
7392 if (conn->rx_len) {
7393 BT_ERR("Unexpected start frame (len %d)", skb->len);
7394 kfree_skb(conn->rx_skb);
7395 conn->rx_skb = NULL;
7396 conn->rx_len = 0;
7397 l2cap_conn_unreliable(conn, ECOMM);
7398 }
7399
7400 /* Start fragment always begin with Basic L2CAP header */
7401 if (skb->len < L2CAP_HDR_SIZE) {
7402 BT_ERR("Frame is too short (len %d)", skb->len);
7403 l2cap_conn_unreliable(conn, ECOMM);
7404 goto drop;
7405 }
7406
7407 hdr = (struct l2cap_hdr *) skb->data;
7408 len = __le16_to_cpu(hdr->len) + L2CAP_HDR_SIZE;
7409
7410 if (len == skb->len) {
7411 /* Complete frame received */
7412 l2cap_recv_frame(conn, skb);
7413 return 0;
7414 }
7415
7416 BT_DBG("Start: total len %d, frag len %d", len, skb->len);
7417
7418 if (skb->len > len) {
7419 BT_ERR("Frame is too long (len %d, expected len %d)",
7420 skb->len, len);
7421 l2cap_conn_unreliable(conn, ECOMM);
7422 goto drop;
7423 }
7424
7425 /* Allocate skb for the complete frame (with header) */
7426 conn->rx_skb = bt_skb_alloc(len, GFP_KERNEL);
7427 if (!conn->rx_skb)
7428 goto drop;
7429
7430 skb_copy_from_linear_data(skb, skb_put(conn->rx_skb, skb->len),
7431 skb->len);
7432 conn->rx_len = len - skb->len;
7433 break;
7434
7435 case ACL_CONT:
7436 BT_DBG("Cont: frag len %d (expecting %d)", skb->len, conn->rx_len);
7437
7438 if (!conn->rx_len) {
7439 BT_ERR("Unexpected continuation frame (len %d)", skb->len);
7440 l2cap_conn_unreliable(conn, ECOMM);
7441 goto drop;
7442 }
7443
7444 if (skb->len > conn->rx_len) {
7445 BT_ERR("Fragment is too long (len %d, expected %d)",
7446 skb->len, conn->rx_len);
7447 kfree_skb(conn->rx_skb);
7448 conn->rx_skb = NULL;
7449 conn->rx_len = 0;
7450 l2cap_conn_unreliable(conn, ECOMM);
7451 goto drop;
7452 }
7453
7454 skb_copy_from_linear_data(skb, skb_put(conn->rx_skb, skb->len),
7455 skb->len);
7456 conn->rx_len -= skb->len;
7457
7458 if (!conn->rx_len) {
7459 /* Complete frame received. l2cap_recv_frame
7460 * takes ownership of the skb so set the global
7461 * rx_skb pointer to NULL first.
7462 */
7463 struct sk_buff *rx_skb = conn->rx_skb;
7464 conn->rx_skb = NULL;
7465 l2cap_recv_frame(conn, rx_skb);
7466 }
7467 break;
7468 }
7469
7470drop:
7471 kfree_skb(skb);
7472 return 0;
7473}
7474
7475static int l2cap_debugfs_show(struct seq_file *f, void *p)
7476{
7477 struct l2cap_chan *c;
7478
7479 read_lock(&chan_list_lock);
7480
7481 list_for_each_entry(c, &chan_list, global_l) {
7482 seq_printf(f, "%pMR %pMR %d %d 0x%4.4x 0x%4.4x %d %d %d %d\n",
7483 &c->src, &c->dst,
7484 c->state, __le16_to_cpu(c->psm),
7485 c->scid, c->dcid, c->imtu, c->omtu,
7486 c->sec_level, c->mode);
7487 }
7488
7489 read_unlock(&chan_list_lock);
7490
7491 return 0;
7492}
7493
7494static int l2cap_debugfs_open(struct inode *inode, struct file *file)
7495{
7496 return single_open(file, l2cap_debugfs_show, inode->i_private);
7497}
7498
7499static const struct file_operations l2cap_debugfs_fops = {
7500 .open = l2cap_debugfs_open,
7501 .read = seq_read,
7502 .llseek = seq_lseek,
7503 .release = single_release,
7504};
7505
7506static struct dentry *l2cap_debugfs;
7507
7508int __init l2cap_init(void)
7509{
7510 int err;
7511
7512 err = l2cap_init_sockets();
7513 if (err < 0)
7514 return err;
7515
7516 if (IS_ERR_OR_NULL(bt_debugfs))
7517 return 0;
7518
7519 l2cap_debugfs = debugfs_create_file("l2cap", 0444, bt_debugfs,
7520 NULL, &l2cap_debugfs_fops);
7521
7522 debugfs_create_u16("l2cap_le_max_credits", 0644, bt_debugfs,
7523 &le_max_credits);
7524 debugfs_create_u16("l2cap_le_default_mps", 0644, bt_debugfs,
7525 &le_default_mps);
7526
7527 bt_6lowpan_init();
7528
7529 return 0;
7530}
7531
7532void l2cap_exit(void)
7533{
7534 bt_6lowpan_cleanup();
7535 debugfs_remove(l2cap_debugfs);
7536 l2cap_cleanup_sockets();
7537}
7538
7539module_param(disable_ertm, bool, 0644);
7540MODULE_PARM_DESC(disable_ertm, "Disable enhanced retransmission mode");