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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/types.h>
34#include <linux/capability.h>
35#include <linux/errno.h>
36#include <linux/kernel.h>
37#include <linux/sched.h>
38#include <linux/slab.h>
39#include <linux/poll.h>
40#include <linux/fcntl.h>
41#include <linux/init.h>
42#include <linux/interrupt.h>
43#include <linux/socket.h>
44#include <linux/skbuff.h>
45#include <linux/list.h>
46#include <linux/device.h>
47#include <linux/debugfs.h>
48#include <linux/seq_file.h>
49#include <linux/uaccess.h>
50#include <linux/crc16.h>
51#include <net/sock.h>
52
53#include <asm/unaligned.h>
54
55#include <net/bluetooth/bluetooth.h>
56#include <net/bluetooth/hci_core.h>
57#include <net/bluetooth/l2cap.h>
58#include <net/bluetooth/smp.h>
59
60bool disable_ertm;
61
62static u32 l2cap_feat_mask = L2CAP_FEAT_FIXED_CHAN;
63static u8 l2cap_fixed_chan[8] = { L2CAP_FC_L2CAP, };
64
65static LIST_HEAD(chan_list);
66static DEFINE_RWLOCK(chan_list_lock);
67
68static struct sk_buff *l2cap_build_cmd(struct l2cap_conn *conn,
69 u8 code, u8 ident, u16 dlen, void *data);
70static void l2cap_send_cmd(struct l2cap_conn *conn, u8 ident, u8 code, u16 len,
71 void *data);
72static int l2cap_build_conf_req(struct l2cap_chan *chan, void *data);
73static void l2cap_send_disconn_req(struct l2cap_conn *conn,
74 struct l2cap_chan *chan, int err);
75
76/* ---- L2CAP channels ---- */
77
78static struct l2cap_chan *__l2cap_get_chan_by_dcid(struct l2cap_conn *conn, u16 cid)
79{
80 struct l2cap_chan *c;
81
82 list_for_each_entry(c, &conn->chan_l, list) {
83 if (c->dcid == cid)
84 return c;
85 }
86 return NULL;
87}
88
89static struct l2cap_chan *__l2cap_get_chan_by_scid(struct l2cap_conn *conn, u16 cid)
90{
91 struct l2cap_chan *c;
92
93 list_for_each_entry(c, &conn->chan_l, list) {
94 if (c->scid == cid)
95 return c;
96 }
97 return NULL;
98}
99
100/* Find channel with given SCID.
101 * Returns locked channel. */
102static struct l2cap_chan *l2cap_get_chan_by_scid(struct l2cap_conn *conn, u16 cid)
103{
104 struct l2cap_chan *c;
105
106 mutex_lock(&conn->chan_lock);
107 c = __l2cap_get_chan_by_scid(conn, cid);
108 if (c)
109 l2cap_chan_lock(c);
110 mutex_unlock(&conn->chan_lock);
111
112 return c;
113}
114
115static struct l2cap_chan *__l2cap_get_chan_by_ident(struct l2cap_conn *conn, u8 ident)
116{
117 struct l2cap_chan *c;
118
119 list_for_each_entry(c, &conn->chan_l, list) {
120 if (c->ident == ident)
121 return c;
122 }
123 return NULL;
124}
125
126static struct l2cap_chan *__l2cap_global_chan_by_addr(__le16 psm, bdaddr_t *src)
127{
128 struct l2cap_chan *c;
129
130 list_for_each_entry(c, &chan_list, global_l) {
131 if (c->sport == psm && !bacmp(&bt_sk(c->sk)->src, src))
132 return c;
133 }
134 return NULL;
135}
136
137int l2cap_add_psm(struct l2cap_chan *chan, bdaddr_t *src, __le16 psm)
138{
139 int err;
140
141 write_lock(&chan_list_lock);
142
143 if (psm && __l2cap_global_chan_by_addr(psm, src)) {
144 err = -EADDRINUSE;
145 goto done;
146 }
147
148 if (psm) {
149 chan->psm = psm;
150 chan->sport = psm;
151 err = 0;
152 } else {
153 u16 p;
154
155 err = -EINVAL;
156 for (p = 0x1001; p < 0x1100; p += 2)
157 if (!__l2cap_global_chan_by_addr(cpu_to_le16(p), src)) {
158 chan->psm = cpu_to_le16(p);
159 chan->sport = cpu_to_le16(p);
160 err = 0;
161 break;
162 }
163 }
164
165done:
166 write_unlock(&chan_list_lock);
167 return err;
168}
169
170int l2cap_add_scid(struct l2cap_chan *chan, __u16 scid)
171{
172 write_lock(&chan_list_lock);
173
174 chan->scid = scid;
175
176 write_unlock(&chan_list_lock);
177
178 return 0;
179}
180
181static u16 l2cap_alloc_cid(struct l2cap_conn *conn)
182{
183 u16 cid = L2CAP_CID_DYN_START;
184
185 for (; cid < L2CAP_CID_DYN_END; cid++) {
186 if (!__l2cap_get_chan_by_scid(conn, cid))
187 return cid;
188 }
189
190 return 0;
191}
192
193static void __l2cap_state_change(struct l2cap_chan *chan, int state)
194{
195 BT_DBG("chan %p %s -> %s", chan, state_to_string(chan->state),
196 state_to_string(state));
197
198 chan->state = state;
199 chan->ops->state_change(chan->data, state);
200}
201
202static void l2cap_state_change(struct l2cap_chan *chan, int state)
203{
204 struct sock *sk = chan->sk;
205
206 lock_sock(sk);
207 __l2cap_state_change(chan, state);
208 release_sock(sk);
209}
210
211static inline void __l2cap_chan_set_err(struct l2cap_chan *chan, int err)
212{
213 struct sock *sk = chan->sk;
214
215 sk->sk_err = err;
216}
217
218static inline void l2cap_chan_set_err(struct l2cap_chan *chan, int err)
219{
220 struct sock *sk = chan->sk;
221
222 lock_sock(sk);
223 __l2cap_chan_set_err(chan, err);
224 release_sock(sk);
225}
226
227/* ---- L2CAP sequence number lists ---- */
228
229/* For ERTM, ordered lists of sequence numbers must be tracked for
230 * SREJ requests that are received and for frames that are to be
231 * retransmitted. These seq_list functions implement a singly-linked
232 * list in an array, where membership in the list can also be checked
233 * in constant time. Items can also be added to the tail of the list
234 * and removed from the head in constant time, without further memory
235 * allocs or frees.
236 */
237
238static int l2cap_seq_list_init(struct l2cap_seq_list *seq_list, u16 size)
239{
240 size_t alloc_size, i;
241
242 /* Allocated size is a power of 2 to map sequence numbers
243 * (which may be up to 14 bits) in to a smaller array that is
244 * sized for the negotiated ERTM transmit windows.
245 */
246 alloc_size = roundup_pow_of_two(size);
247
248 seq_list->list = kmalloc(sizeof(u16) * alloc_size, GFP_KERNEL);
249 if (!seq_list->list)
250 return -ENOMEM;
251
252 seq_list->mask = alloc_size - 1;
253 seq_list->head = L2CAP_SEQ_LIST_CLEAR;
254 seq_list->tail = L2CAP_SEQ_LIST_CLEAR;
255 for (i = 0; i < alloc_size; i++)
256 seq_list->list[i] = L2CAP_SEQ_LIST_CLEAR;
257
258 return 0;
259}
260
261static inline void l2cap_seq_list_free(struct l2cap_seq_list *seq_list)
262{
263 kfree(seq_list->list);
264}
265
266static inline bool l2cap_seq_list_contains(struct l2cap_seq_list *seq_list,
267 u16 seq)
268{
269 /* Constant-time check for list membership */
270 return seq_list->list[seq & seq_list->mask] != L2CAP_SEQ_LIST_CLEAR;
271}
272
273static u16 l2cap_seq_list_remove(struct l2cap_seq_list *seq_list, u16 seq)
274{
275 u16 mask = seq_list->mask;
276
277 if (seq_list->head == L2CAP_SEQ_LIST_CLEAR) {
278 /* In case someone tries to pop the head of an empty list */
279 return L2CAP_SEQ_LIST_CLEAR;
280 } else if (seq_list->head == seq) {
281 /* Head can be removed in constant time */
282 seq_list->head = seq_list->list[seq & mask];
283 seq_list->list[seq & mask] = L2CAP_SEQ_LIST_CLEAR;
284
285 if (seq_list->head == L2CAP_SEQ_LIST_TAIL) {
286 seq_list->head = L2CAP_SEQ_LIST_CLEAR;
287 seq_list->tail = L2CAP_SEQ_LIST_CLEAR;
288 }
289 } else {
290 /* Walk the list to find the sequence number */
291 u16 prev = seq_list->head;
292 while (seq_list->list[prev & mask] != seq) {
293 prev = seq_list->list[prev & mask];
294 if (prev == L2CAP_SEQ_LIST_TAIL)
295 return L2CAP_SEQ_LIST_CLEAR;
296 }
297
298 /* Unlink the number from the list and clear it */
299 seq_list->list[prev & mask] = seq_list->list[seq & mask];
300 seq_list->list[seq & mask] = L2CAP_SEQ_LIST_CLEAR;
301 if (seq_list->tail == seq)
302 seq_list->tail = prev;
303 }
304 return seq;
305}
306
307static inline u16 l2cap_seq_list_pop(struct l2cap_seq_list *seq_list)
308{
309 /* Remove the head in constant time */
310 return l2cap_seq_list_remove(seq_list, seq_list->head);
311}
312
313static void l2cap_seq_list_clear(struct l2cap_seq_list *seq_list)
314{
315 u16 i;
316
317 if (seq_list->head == L2CAP_SEQ_LIST_CLEAR)
318 return;
319
320 for (i = 0; i <= seq_list->mask; i++)
321 seq_list->list[i] = L2CAP_SEQ_LIST_CLEAR;
322
323 seq_list->head = L2CAP_SEQ_LIST_CLEAR;
324 seq_list->tail = L2CAP_SEQ_LIST_CLEAR;
325}
326
327static void l2cap_seq_list_append(struct l2cap_seq_list *seq_list, u16 seq)
328{
329 u16 mask = seq_list->mask;
330
331 /* All appends happen in constant time */
332
333 if (seq_list->list[seq & mask] != L2CAP_SEQ_LIST_CLEAR)
334 return;
335
336 if (seq_list->tail == L2CAP_SEQ_LIST_CLEAR)
337 seq_list->head = seq;
338 else
339 seq_list->list[seq_list->tail & mask] = seq;
340
341 seq_list->tail = seq;
342 seq_list->list[seq & mask] = L2CAP_SEQ_LIST_TAIL;
343}
344
345static void l2cap_chan_timeout(struct work_struct *work)
346{
347 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
348 chan_timer.work);
349 struct l2cap_conn *conn = chan->conn;
350 int reason;
351
352 BT_DBG("chan %p state %s", chan, state_to_string(chan->state));
353
354 mutex_lock(&conn->chan_lock);
355 l2cap_chan_lock(chan);
356
357 if (chan->state == BT_CONNECTED || chan->state == BT_CONFIG)
358 reason = ECONNREFUSED;
359 else if (chan->state == BT_CONNECT &&
360 chan->sec_level != BT_SECURITY_SDP)
361 reason = ECONNREFUSED;
362 else
363 reason = ETIMEDOUT;
364
365 l2cap_chan_close(chan, reason);
366
367 l2cap_chan_unlock(chan);
368
369 chan->ops->close(chan->data);
370 mutex_unlock(&conn->chan_lock);
371
372 l2cap_chan_put(chan);
373}
374
375struct l2cap_chan *l2cap_chan_create(void)
376{
377 struct l2cap_chan *chan;
378
379 chan = kzalloc(sizeof(*chan), GFP_ATOMIC);
380 if (!chan)
381 return NULL;
382
383 mutex_init(&chan->lock);
384
385 write_lock(&chan_list_lock);
386 list_add(&chan->global_l, &chan_list);
387 write_unlock(&chan_list_lock);
388
389 INIT_DELAYED_WORK(&chan->chan_timer, l2cap_chan_timeout);
390
391 chan->state = BT_OPEN;
392
393 atomic_set(&chan->refcnt, 1);
394
395 BT_DBG("chan %p", chan);
396
397 return chan;
398}
399
400void l2cap_chan_destroy(struct l2cap_chan *chan)
401{
402 write_lock(&chan_list_lock);
403 list_del(&chan->global_l);
404 write_unlock(&chan_list_lock);
405
406 l2cap_chan_put(chan);
407}
408
409void l2cap_chan_set_defaults(struct l2cap_chan *chan)
410{
411 chan->fcs = L2CAP_FCS_CRC16;
412 chan->max_tx = L2CAP_DEFAULT_MAX_TX;
413 chan->tx_win = L2CAP_DEFAULT_TX_WINDOW;
414 chan->tx_win_max = L2CAP_DEFAULT_TX_WINDOW;
415 chan->sec_level = BT_SECURITY_LOW;
416
417 set_bit(FLAG_FORCE_ACTIVE, &chan->flags);
418}
419
420static void __l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan)
421{
422 BT_DBG("conn %p, psm 0x%2.2x, dcid 0x%4.4x", conn,
423 __le16_to_cpu(chan->psm), chan->dcid);
424
425 conn->disc_reason = HCI_ERROR_REMOTE_USER_TERM;
426
427 chan->conn = conn;
428
429 switch (chan->chan_type) {
430 case L2CAP_CHAN_CONN_ORIENTED:
431 if (conn->hcon->type == LE_LINK) {
432 /* LE connection */
433 chan->omtu = L2CAP_LE_DEFAULT_MTU;
434 chan->scid = L2CAP_CID_LE_DATA;
435 chan->dcid = L2CAP_CID_LE_DATA;
436 } else {
437 /* Alloc CID for connection-oriented socket */
438 chan->scid = l2cap_alloc_cid(conn);
439 chan->omtu = L2CAP_DEFAULT_MTU;
440 }
441 break;
442
443 case L2CAP_CHAN_CONN_LESS:
444 /* Connectionless socket */
445 chan->scid = L2CAP_CID_CONN_LESS;
446 chan->dcid = L2CAP_CID_CONN_LESS;
447 chan->omtu = L2CAP_DEFAULT_MTU;
448 break;
449
450 default:
451 /* Raw socket can send/recv signalling messages only */
452 chan->scid = L2CAP_CID_SIGNALING;
453 chan->dcid = L2CAP_CID_SIGNALING;
454 chan->omtu = L2CAP_DEFAULT_MTU;
455 }
456
457 chan->local_id = L2CAP_BESTEFFORT_ID;
458 chan->local_stype = L2CAP_SERV_BESTEFFORT;
459 chan->local_msdu = L2CAP_DEFAULT_MAX_SDU_SIZE;
460 chan->local_sdu_itime = L2CAP_DEFAULT_SDU_ITIME;
461 chan->local_acc_lat = L2CAP_DEFAULT_ACC_LAT;
462 chan->local_flush_to = L2CAP_DEFAULT_FLUSH_TO;
463
464 l2cap_chan_hold(chan);
465
466 list_add(&chan->list, &conn->chan_l);
467}
468
469static void l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan)
470{
471 mutex_lock(&conn->chan_lock);
472 __l2cap_chan_add(conn, chan);
473 mutex_unlock(&conn->chan_lock);
474}
475
476static void l2cap_chan_del(struct l2cap_chan *chan, int err)
477{
478 struct sock *sk = chan->sk;
479 struct l2cap_conn *conn = chan->conn;
480 struct sock *parent = bt_sk(sk)->parent;
481
482 __clear_chan_timer(chan);
483
484 BT_DBG("chan %p, conn %p, err %d", chan, conn, err);
485
486 if (conn) {
487 /* Delete from channel list */
488 list_del(&chan->list);
489
490 l2cap_chan_put(chan);
491
492 chan->conn = NULL;
493 hci_conn_put(conn->hcon);
494 }
495
496 lock_sock(sk);
497
498 __l2cap_state_change(chan, BT_CLOSED);
499 sock_set_flag(sk, SOCK_ZAPPED);
500
501 if (err)
502 __l2cap_chan_set_err(chan, err);
503
504 if (parent) {
505 bt_accept_unlink(sk);
506 parent->sk_data_ready(parent, 0);
507 } else
508 sk->sk_state_change(sk);
509
510 release_sock(sk);
511
512 if (!(test_bit(CONF_OUTPUT_DONE, &chan->conf_state) &&
513 test_bit(CONF_INPUT_DONE, &chan->conf_state)))
514 return;
515
516 skb_queue_purge(&chan->tx_q);
517
518 if (chan->mode == L2CAP_MODE_ERTM) {
519 struct srej_list *l, *tmp;
520
521 __clear_retrans_timer(chan);
522 __clear_monitor_timer(chan);
523 __clear_ack_timer(chan);
524
525 skb_queue_purge(&chan->srej_q);
526
527 l2cap_seq_list_free(&chan->srej_list);
528 l2cap_seq_list_free(&chan->retrans_list);
529 list_for_each_entry_safe(l, tmp, &chan->srej_l, list) {
530 list_del(&l->list);
531 kfree(l);
532 }
533 }
534}
535
536static void l2cap_chan_cleanup_listen(struct sock *parent)
537{
538 struct sock *sk;
539
540 BT_DBG("parent %p", parent);
541
542 /* Close not yet accepted channels */
543 while ((sk = bt_accept_dequeue(parent, NULL))) {
544 struct l2cap_chan *chan = l2cap_pi(sk)->chan;
545
546 l2cap_chan_lock(chan);
547 __clear_chan_timer(chan);
548 l2cap_chan_close(chan, ECONNRESET);
549 l2cap_chan_unlock(chan);
550
551 chan->ops->close(chan->data);
552 }
553}
554
555void l2cap_chan_close(struct l2cap_chan *chan, int reason)
556{
557 struct l2cap_conn *conn = chan->conn;
558 struct sock *sk = chan->sk;
559
560 BT_DBG("chan %p state %s sk %p", chan,
561 state_to_string(chan->state), sk);
562
563 switch (chan->state) {
564 case BT_LISTEN:
565 lock_sock(sk);
566 l2cap_chan_cleanup_listen(sk);
567
568 __l2cap_state_change(chan, BT_CLOSED);
569 sock_set_flag(sk, SOCK_ZAPPED);
570 release_sock(sk);
571 break;
572
573 case BT_CONNECTED:
574 case BT_CONFIG:
575 if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED &&
576 conn->hcon->type == ACL_LINK) {
577 __set_chan_timer(chan, sk->sk_sndtimeo);
578 l2cap_send_disconn_req(conn, chan, reason);
579 } else
580 l2cap_chan_del(chan, reason);
581 break;
582
583 case BT_CONNECT2:
584 if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED &&
585 conn->hcon->type == ACL_LINK) {
586 struct l2cap_conn_rsp rsp;
587 __u16 result;
588
589 if (test_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags))
590 result = L2CAP_CR_SEC_BLOCK;
591 else
592 result = L2CAP_CR_BAD_PSM;
593 l2cap_state_change(chan, BT_DISCONN);
594
595 rsp.scid = cpu_to_le16(chan->dcid);
596 rsp.dcid = cpu_to_le16(chan->scid);
597 rsp.result = cpu_to_le16(result);
598 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
599 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP,
600 sizeof(rsp), &rsp);
601 }
602
603 l2cap_chan_del(chan, reason);
604 break;
605
606 case BT_CONNECT:
607 case BT_DISCONN:
608 l2cap_chan_del(chan, reason);
609 break;
610
611 default:
612 lock_sock(sk);
613 sock_set_flag(sk, SOCK_ZAPPED);
614 release_sock(sk);
615 break;
616 }
617}
618
619static inline u8 l2cap_get_auth_type(struct l2cap_chan *chan)
620{
621 if (chan->chan_type == L2CAP_CHAN_RAW) {
622 switch (chan->sec_level) {
623 case BT_SECURITY_HIGH:
624 return HCI_AT_DEDICATED_BONDING_MITM;
625 case BT_SECURITY_MEDIUM:
626 return HCI_AT_DEDICATED_BONDING;
627 default:
628 return HCI_AT_NO_BONDING;
629 }
630 } else if (chan->psm == cpu_to_le16(0x0001)) {
631 if (chan->sec_level == BT_SECURITY_LOW)
632 chan->sec_level = BT_SECURITY_SDP;
633
634 if (chan->sec_level == BT_SECURITY_HIGH)
635 return HCI_AT_NO_BONDING_MITM;
636 else
637 return HCI_AT_NO_BONDING;
638 } else {
639 switch (chan->sec_level) {
640 case BT_SECURITY_HIGH:
641 return HCI_AT_GENERAL_BONDING_MITM;
642 case BT_SECURITY_MEDIUM:
643 return HCI_AT_GENERAL_BONDING;
644 default:
645 return HCI_AT_NO_BONDING;
646 }
647 }
648}
649
650/* Service level security */
651int l2cap_chan_check_security(struct l2cap_chan *chan)
652{
653 struct l2cap_conn *conn = chan->conn;
654 __u8 auth_type;
655
656 auth_type = l2cap_get_auth_type(chan);
657
658 return hci_conn_security(conn->hcon, chan->sec_level, auth_type);
659}
660
661static u8 l2cap_get_ident(struct l2cap_conn *conn)
662{
663 u8 id;
664
665 /* Get next available identificator.
666 * 1 - 128 are used by kernel.
667 * 129 - 199 are reserved.
668 * 200 - 254 are used by utilities like l2ping, etc.
669 */
670
671 spin_lock(&conn->lock);
672
673 if (++conn->tx_ident > 128)
674 conn->tx_ident = 1;
675
676 id = conn->tx_ident;
677
678 spin_unlock(&conn->lock);
679
680 return id;
681}
682
683static void l2cap_send_cmd(struct l2cap_conn *conn, u8 ident, u8 code, u16 len, void *data)
684{
685 struct sk_buff *skb = l2cap_build_cmd(conn, code, ident, len, data);
686 u8 flags;
687
688 BT_DBG("code 0x%2.2x", code);
689
690 if (!skb)
691 return;
692
693 if (lmp_no_flush_capable(conn->hcon->hdev))
694 flags = ACL_START_NO_FLUSH;
695 else
696 flags = ACL_START;
697
698 bt_cb(skb)->force_active = BT_POWER_FORCE_ACTIVE_ON;
699 skb->priority = HCI_PRIO_MAX;
700
701 hci_send_acl(conn->hchan, skb, flags);
702}
703
704static void l2cap_do_send(struct l2cap_chan *chan, struct sk_buff *skb)
705{
706 struct hci_conn *hcon = chan->conn->hcon;
707 u16 flags;
708
709 BT_DBG("chan %p, skb %p len %d priority %u", chan, skb, skb->len,
710 skb->priority);
711
712 if (!test_bit(FLAG_FLUSHABLE, &chan->flags) &&
713 lmp_no_flush_capable(hcon->hdev))
714 flags = ACL_START_NO_FLUSH;
715 else
716 flags = ACL_START;
717
718 bt_cb(skb)->force_active = test_bit(FLAG_FORCE_ACTIVE, &chan->flags);
719 hci_send_acl(chan->conn->hchan, skb, flags);
720}
721
722static void __unpack_enhanced_control(u16 enh, struct l2cap_ctrl *control)
723{
724 control->reqseq = (enh & L2CAP_CTRL_REQSEQ) >> L2CAP_CTRL_REQSEQ_SHIFT;
725 control->final = (enh & L2CAP_CTRL_FINAL) >> L2CAP_CTRL_FINAL_SHIFT;
726
727 if (enh & L2CAP_CTRL_FRAME_TYPE) {
728 /* S-Frame */
729 control->sframe = 1;
730 control->poll = (enh & L2CAP_CTRL_POLL) >> L2CAP_CTRL_POLL_SHIFT;
731 control->super = (enh & L2CAP_CTRL_SUPERVISE) >> L2CAP_CTRL_SUPER_SHIFT;
732
733 control->sar = 0;
734 control->txseq = 0;
735 } else {
736 /* I-Frame */
737 control->sframe = 0;
738 control->sar = (enh & L2CAP_CTRL_SAR) >> L2CAP_CTRL_SAR_SHIFT;
739 control->txseq = (enh & L2CAP_CTRL_TXSEQ) >> L2CAP_CTRL_TXSEQ_SHIFT;
740
741 control->poll = 0;
742 control->super = 0;
743 }
744}
745
746static void __unpack_extended_control(u32 ext, struct l2cap_ctrl *control)
747{
748 control->reqseq = (ext & L2CAP_EXT_CTRL_REQSEQ) >> L2CAP_EXT_CTRL_REQSEQ_SHIFT;
749 control->final = (ext & L2CAP_EXT_CTRL_FINAL) >> L2CAP_EXT_CTRL_FINAL_SHIFT;
750
751 if (ext & L2CAP_EXT_CTRL_FRAME_TYPE) {
752 /* S-Frame */
753 control->sframe = 1;
754 control->poll = (ext & L2CAP_EXT_CTRL_POLL) >> L2CAP_EXT_CTRL_POLL_SHIFT;
755 control->super = (ext & L2CAP_EXT_CTRL_SUPERVISE) >> L2CAP_EXT_CTRL_SUPER_SHIFT;
756
757 control->sar = 0;
758 control->txseq = 0;
759 } else {
760 /* I-Frame */
761 control->sframe = 0;
762 control->sar = (ext & L2CAP_EXT_CTRL_SAR) >> L2CAP_EXT_CTRL_SAR_SHIFT;
763 control->txseq = (ext & L2CAP_EXT_CTRL_TXSEQ) >> L2CAP_EXT_CTRL_TXSEQ_SHIFT;
764
765 control->poll = 0;
766 control->super = 0;
767 }
768}
769
770static inline void __unpack_control(struct l2cap_chan *chan,
771 struct sk_buff *skb)
772{
773 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) {
774 __unpack_extended_control(get_unaligned_le32(skb->data),
775 &bt_cb(skb)->control);
776 } else {
777 __unpack_enhanced_control(get_unaligned_le16(skb->data),
778 &bt_cb(skb)->control);
779 }
780}
781
782static u32 __pack_extended_control(struct l2cap_ctrl *control)
783{
784 u32 packed;
785
786 packed = control->reqseq << L2CAP_EXT_CTRL_REQSEQ_SHIFT;
787 packed |= control->final << L2CAP_EXT_CTRL_FINAL_SHIFT;
788
789 if (control->sframe) {
790 packed |= control->poll << L2CAP_EXT_CTRL_POLL_SHIFT;
791 packed |= control->super << L2CAP_EXT_CTRL_SUPER_SHIFT;
792 packed |= L2CAP_EXT_CTRL_FRAME_TYPE;
793 } else {
794 packed |= control->sar << L2CAP_EXT_CTRL_SAR_SHIFT;
795 packed |= control->txseq << L2CAP_EXT_CTRL_TXSEQ_SHIFT;
796 }
797
798 return packed;
799}
800
801static u16 __pack_enhanced_control(struct l2cap_ctrl *control)
802{
803 u16 packed;
804
805 packed = control->reqseq << L2CAP_CTRL_REQSEQ_SHIFT;
806 packed |= control->final << L2CAP_CTRL_FINAL_SHIFT;
807
808 if (control->sframe) {
809 packed |= control->poll << L2CAP_CTRL_POLL_SHIFT;
810 packed |= control->super << L2CAP_CTRL_SUPER_SHIFT;
811 packed |= L2CAP_CTRL_FRAME_TYPE;
812 } else {
813 packed |= control->sar << L2CAP_CTRL_SAR_SHIFT;
814 packed |= control->txseq << L2CAP_CTRL_TXSEQ_SHIFT;
815 }
816
817 return packed;
818}
819
820static inline void __pack_control(struct l2cap_chan *chan,
821 struct l2cap_ctrl *control,
822 struct sk_buff *skb)
823{
824 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) {
825 put_unaligned_le32(__pack_extended_control(control),
826 skb->data + L2CAP_HDR_SIZE);
827 } else {
828 put_unaligned_le16(__pack_enhanced_control(control),
829 skb->data + L2CAP_HDR_SIZE);
830 }
831}
832
833static inline void l2cap_send_sframe(struct l2cap_chan *chan, u32 control)
834{
835 struct sk_buff *skb;
836 struct l2cap_hdr *lh;
837 struct l2cap_conn *conn = chan->conn;
838 int count, hlen;
839
840 if (chan->state != BT_CONNECTED)
841 return;
842
843 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
844 hlen = L2CAP_EXT_HDR_SIZE;
845 else
846 hlen = L2CAP_ENH_HDR_SIZE;
847
848 if (chan->fcs == L2CAP_FCS_CRC16)
849 hlen += L2CAP_FCS_SIZE;
850
851 BT_DBG("chan %p, control 0x%8.8x", chan, control);
852
853 count = min_t(unsigned int, conn->mtu, hlen);
854
855 control |= __set_sframe(chan);
856
857 if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state))
858 control |= __set_ctrl_final(chan);
859
860 if (test_and_clear_bit(CONN_SEND_PBIT, &chan->conn_state))
861 control |= __set_ctrl_poll(chan);
862
863 skb = bt_skb_alloc(count, GFP_ATOMIC);
864 if (!skb)
865 return;
866
867 lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
868 lh->len = cpu_to_le16(hlen - L2CAP_HDR_SIZE);
869 lh->cid = cpu_to_le16(chan->dcid);
870
871 __put_control(chan, control, skb_put(skb, __ctrl_size(chan)));
872
873 if (chan->fcs == L2CAP_FCS_CRC16) {
874 u16 fcs = crc16(0, (u8 *)lh, count - L2CAP_FCS_SIZE);
875 put_unaligned_le16(fcs, skb_put(skb, L2CAP_FCS_SIZE));
876 }
877
878 skb->priority = HCI_PRIO_MAX;
879 l2cap_do_send(chan, skb);
880}
881
882static inline void l2cap_send_rr_or_rnr(struct l2cap_chan *chan, u32 control)
883{
884 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
885 control |= __set_ctrl_super(chan, L2CAP_SUPER_RNR);
886 set_bit(CONN_RNR_SENT, &chan->conn_state);
887 } else
888 control |= __set_ctrl_super(chan, L2CAP_SUPER_RR);
889
890 control |= __set_reqseq(chan, chan->buffer_seq);
891
892 l2cap_send_sframe(chan, control);
893}
894
895static inline int __l2cap_no_conn_pending(struct l2cap_chan *chan)
896{
897 return !test_bit(CONF_CONNECT_PEND, &chan->conf_state);
898}
899
900static void l2cap_send_conn_req(struct l2cap_chan *chan)
901{
902 struct l2cap_conn *conn = chan->conn;
903 struct l2cap_conn_req req;
904
905 req.scid = cpu_to_le16(chan->scid);
906 req.psm = chan->psm;
907
908 chan->ident = l2cap_get_ident(conn);
909
910 set_bit(CONF_CONNECT_PEND, &chan->conf_state);
911
912 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_REQ, sizeof(req), &req);
913}
914
915static void l2cap_chan_ready(struct l2cap_chan *chan)
916{
917 struct sock *sk = chan->sk;
918 struct sock *parent;
919
920 lock_sock(sk);
921
922 parent = bt_sk(sk)->parent;
923
924 BT_DBG("sk %p, parent %p", sk, parent);
925
926 chan->conf_state = 0;
927 __clear_chan_timer(chan);
928
929 __l2cap_state_change(chan, BT_CONNECTED);
930 sk->sk_state_change(sk);
931
932 if (parent)
933 parent->sk_data_ready(parent, 0);
934
935 release_sock(sk);
936}
937
938static void l2cap_do_start(struct l2cap_chan *chan)
939{
940 struct l2cap_conn *conn = chan->conn;
941
942 if (conn->hcon->type == LE_LINK) {
943 l2cap_chan_ready(chan);
944 return;
945 }
946
947 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT) {
948 if (!(conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE))
949 return;
950
951 if (l2cap_chan_check_security(chan) &&
952 __l2cap_no_conn_pending(chan))
953 l2cap_send_conn_req(chan);
954 } else {
955 struct l2cap_info_req req;
956 req.type = cpu_to_le16(L2CAP_IT_FEAT_MASK);
957
958 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_SENT;
959 conn->info_ident = l2cap_get_ident(conn);
960
961 schedule_delayed_work(&conn->info_timer, L2CAP_INFO_TIMEOUT);
962
963 l2cap_send_cmd(conn, conn->info_ident,
964 L2CAP_INFO_REQ, sizeof(req), &req);
965 }
966}
967
968static inline int l2cap_mode_supported(__u8 mode, __u32 feat_mask)
969{
970 u32 local_feat_mask = l2cap_feat_mask;
971 if (!disable_ertm)
972 local_feat_mask |= L2CAP_FEAT_ERTM | L2CAP_FEAT_STREAMING;
973
974 switch (mode) {
975 case L2CAP_MODE_ERTM:
976 return L2CAP_FEAT_ERTM & feat_mask & local_feat_mask;
977 case L2CAP_MODE_STREAMING:
978 return L2CAP_FEAT_STREAMING & feat_mask & local_feat_mask;
979 default:
980 return 0x00;
981 }
982}
983
984static void l2cap_send_disconn_req(struct l2cap_conn *conn, struct l2cap_chan *chan, int err)
985{
986 struct sock *sk = chan->sk;
987 struct l2cap_disconn_req req;
988
989 if (!conn)
990 return;
991
992 if (chan->mode == L2CAP_MODE_ERTM) {
993 __clear_retrans_timer(chan);
994 __clear_monitor_timer(chan);
995 __clear_ack_timer(chan);
996 }
997
998 req.dcid = cpu_to_le16(chan->dcid);
999 req.scid = cpu_to_le16(chan->scid);
1000 l2cap_send_cmd(conn, l2cap_get_ident(conn),
1001 L2CAP_DISCONN_REQ, sizeof(req), &req);
1002
1003 lock_sock(sk);
1004 __l2cap_state_change(chan, BT_DISCONN);
1005 __l2cap_chan_set_err(chan, err);
1006 release_sock(sk);
1007}
1008
1009/* ---- L2CAP connections ---- */
1010static void l2cap_conn_start(struct l2cap_conn *conn)
1011{
1012 struct l2cap_chan *chan, *tmp;
1013
1014 BT_DBG("conn %p", conn);
1015
1016 mutex_lock(&conn->chan_lock);
1017
1018 list_for_each_entry_safe(chan, tmp, &conn->chan_l, list) {
1019 struct sock *sk = chan->sk;
1020
1021 l2cap_chan_lock(chan);
1022
1023 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
1024 l2cap_chan_unlock(chan);
1025 continue;
1026 }
1027
1028 if (chan->state == BT_CONNECT) {
1029 if (!l2cap_chan_check_security(chan) ||
1030 !__l2cap_no_conn_pending(chan)) {
1031 l2cap_chan_unlock(chan);
1032 continue;
1033 }
1034
1035 if (!l2cap_mode_supported(chan->mode, conn->feat_mask)
1036 && test_bit(CONF_STATE2_DEVICE,
1037 &chan->conf_state)) {
1038 l2cap_chan_close(chan, ECONNRESET);
1039 l2cap_chan_unlock(chan);
1040 continue;
1041 }
1042
1043 l2cap_send_conn_req(chan);
1044
1045 } else if (chan->state == BT_CONNECT2) {
1046 struct l2cap_conn_rsp rsp;
1047 char buf[128];
1048 rsp.scid = cpu_to_le16(chan->dcid);
1049 rsp.dcid = cpu_to_le16(chan->scid);
1050
1051 if (l2cap_chan_check_security(chan)) {
1052 lock_sock(sk);
1053 if (test_bit(BT_SK_DEFER_SETUP,
1054 &bt_sk(sk)->flags)) {
1055 struct sock *parent = bt_sk(sk)->parent;
1056 rsp.result = cpu_to_le16(L2CAP_CR_PEND);
1057 rsp.status = cpu_to_le16(L2CAP_CS_AUTHOR_PEND);
1058 if (parent)
1059 parent->sk_data_ready(parent, 0);
1060
1061 } else {
1062 __l2cap_state_change(chan, BT_CONFIG);
1063 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
1064 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
1065 }
1066 release_sock(sk);
1067 } else {
1068 rsp.result = cpu_to_le16(L2CAP_CR_PEND);
1069 rsp.status = cpu_to_le16(L2CAP_CS_AUTHEN_PEND);
1070 }
1071
1072 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP,
1073 sizeof(rsp), &rsp);
1074
1075 if (test_bit(CONF_REQ_SENT, &chan->conf_state) ||
1076 rsp.result != L2CAP_CR_SUCCESS) {
1077 l2cap_chan_unlock(chan);
1078 continue;
1079 }
1080
1081 set_bit(CONF_REQ_SENT, &chan->conf_state);
1082 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
1083 l2cap_build_conf_req(chan, buf), buf);
1084 chan->num_conf_req++;
1085 }
1086
1087 l2cap_chan_unlock(chan);
1088 }
1089
1090 mutex_unlock(&conn->chan_lock);
1091}
1092
1093/* Find socket with cid and source/destination bdaddr.
1094 * Returns closest match, locked.
1095 */
1096static struct l2cap_chan *l2cap_global_chan_by_scid(int state, u16 cid,
1097 bdaddr_t *src,
1098 bdaddr_t *dst)
1099{
1100 struct l2cap_chan *c, *c1 = NULL;
1101
1102 read_lock(&chan_list_lock);
1103
1104 list_for_each_entry(c, &chan_list, global_l) {
1105 struct sock *sk = c->sk;
1106
1107 if (state && c->state != state)
1108 continue;
1109
1110 if (c->scid == cid) {
1111 int src_match, dst_match;
1112 int src_any, dst_any;
1113
1114 /* Exact match. */
1115 src_match = !bacmp(&bt_sk(sk)->src, src);
1116 dst_match = !bacmp(&bt_sk(sk)->dst, dst);
1117 if (src_match && dst_match) {
1118 read_unlock(&chan_list_lock);
1119 return c;
1120 }
1121
1122 /* Closest match */
1123 src_any = !bacmp(&bt_sk(sk)->src, BDADDR_ANY);
1124 dst_any = !bacmp(&bt_sk(sk)->dst, BDADDR_ANY);
1125 if ((src_match && dst_any) || (src_any && dst_match) ||
1126 (src_any && dst_any))
1127 c1 = c;
1128 }
1129 }
1130
1131 read_unlock(&chan_list_lock);
1132
1133 return c1;
1134}
1135
1136static void l2cap_le_conn_ready(struct l2cap_conn *conn)
1137{
1138 struct sock *parent, *sk;
1139 struct l2cap_chan *chan, *pchan;
1140
1141 BT_DBG("");
1142
1143 /* Check if we have socket listening on cid */
1144 pchan = l2cap_global_chan_by_scid(BT_LISTEN, L2CAP_CID_LE_DATA,
1145 conn->src, conn->dst);
1146 if (!pchan)
1147 return;
1148
1149 parent = pchan->sk;
1150
1151 lock_sock(parent);
1152
1153 /* Check for backlog size */
1154 if (sk_acceptq_is_full(parent)) {
1155 BT_DBG("backlog full %d", parent->sk_ack_backlog);
1156 goto clean;
1157 }
1158
1159 chan = pchan->ops->new_connection(pchan->data);
1160 if (!chan)
1161 goto clean;
1162
1163 sk = chan->sk;
1164
1165 hci_conn_hold(conn->hcon);
1166 conn->hcon->disc_timeout = HCI_DISCONN_TIMEOUT;
1167
1168 bacpy(&bt_sk(sk)->src, conn->src);
1169 bacpy(&bt_sk(sk)->dst, conn->dst);
1170
1171 bt_accept_enqueue(parent, sk);
1172
1173 l2cap_chan_add(conn, chan);
1174
1175 __set_chan_timer(chan, sk->sk_sndtimeo);
1176
1177 __l2cap_state_change(chan, BT_CONNECTED);
1178 parent->sk_data_ready(parent, 0);
1179
1180clean:
1181 release_sock(parent);
1182}
1183
1184static void l2cap_conn_ready(struct l2cap_conn *conn)
1185{
1186 struct l2cap_chan *chan;
1187 struct hci_conn *hcon = conn->hcon;
1188
1189 BT_DBG("conn %p", conn);
1190
1191 if (!hcon->out && hcon->type == LE_LINK)
1192 l2cap_le_conn_ready(conn);
1193
1194 if (hcon->out && hcon->type == LE_LINK)
1195 smp_conn_security(hcon, hcon->pending_sec_level);
1196
1197 mutex_lock(&conn->chan_lock);
1198
1199 list_for_each_entry(chan, &conn->chan_l, list) {
1200
1201 l2cap_chan_lock(chan);
1202
1203 if (hcon->type == LE_LINK) {
1204 if (smp_conn_security(hcon, chan->sec_level))
1205 l2cap_chan_ready(chan);
1206
1207 } else if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
1208 struct sock *sk = chan->sk;
1209 __clear_chan_timer(chan);
1210 lock_sock(sk);
1211 __l2cap_state_change(chan, BT_CONNECTED);
1212 sk->sk_state_change(sk);
1213 release_sock(sk);
1214
1215 } else if (chan->state == BT_CONNECT)
1216 l2cap_do_start(chan);
1217
1218 l2cap_chan_unlock(chan);
1219 }
1220
1221 mutex_unlock(&conn->chan_lock);
1222}
1223
1224/* Notify sockets that we cannot guaranty reliability anymore */
1225static void l2cap_conn_unreliable(struct l2cap_conn *conn, int err)
1226{
1227 struct l2cap_chan *chan;
1228
1229 BT_DBG("conn %p", conn);
1230
1231 mutex_lock(&conn->chan_lock);
1232
1233 list_for_each_entry(chan, &conn->chan_l, list) {
1234 if (test_bit(FLAG_FORCE_RELIABLE, &chan->flags))
1235 __l2cap_chan_set_err(chan, err);
1236 }
1237
1238 mutex_unlock(&conn->chan_lock);
1239}
1240
1241static void l2cap_info_timeout(struct work_struct *work)
1242{
1243 struct l2cap_conn *conn = container_of(work, struct l2cap_conn,
1244 info_timer.work);
1245
1246 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
1247 conn->info_ident = 0;
1248
1249 l2cap_conn_start(conn);
1250}
1251
1252static void l2cap_conn_del(struct hci_conn *hcon, int err)
1253{
1254 struct l2cap_conn *conn = hcon->l2cap_data;
1255 struct l2cap_chan *chan, *l;
1256
1257 if (!conn)
1258 return;
1259
1260 BT_DBG("hcon %p conn %p, err %d", hcon, conn, err);
1261
1262 kfree_skb(conn->rx_skb);
1263
1264 mutex_lock(&conn->chan_lock);
1265
1266 /* Kill channels */
1267 list_for_each_entry_safe(chan, l, &conn->chan_l, list) {
1268 l2cap_chan_hold(chan);
1269 l2cap_chan_lock(chan);
1270
1271 l2cap_chan_del(chan, err);
1272
1273 l2cap_chan_unlock(chan);
1274
1275 chan->ops->close(chan->data);
1276 l2cap_chan_put(chan);
1277 }
1278
1279 mutex_unlock(&conn->chan_lock);
1280
1281 hci_chan_del(conn->hchan);
1282
1283 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT)
1284 cancel_delayed_work_sync(&conn->info_timer);
1285
1286 if (test_and_clear_bit(HCI_CONN_LE_SMP_PEND, &hcon->flags)) {
1287 cancel_delayed_work_sync(&conn->security_timer);
1288 smp_chan_destroy(conn);
1289 }
1290
1291 hcon->l2cap_data = NULL;
1292 kfree(conn);
1293}
1294
1295static void security_timeout(struct work_struct *work)
1296{
1297 struct l2cap_conn *conn = container_of(work, struct l2cap_conn,
1298 security_timer.work);
1299
1300 BT_DBG("conn %p", conn);
1301
1302 if (test_and_clear_bit(HCI_CONN_LE_SMP_PEND, &conn->hcon->flags)) {
1303 smp_chan_destroy(conn);
1304 l2cap_conn_del(conn->hcon, ETIMEDOUT);
1305 }
1306}
1307
1308static struct l2cap_conn *l2cap_conn_add(struct hci_conn *hcon, u8 status)
1309{
1310 struct l2cap_conn *conn = hcon->l2cap_data;
1311 struct hci_chan *hchan;
1312
1313 if (conn || status)
1314 return conn;
1315
1316 hchan = hci_chan_create(hcon);
1317 if (!hchan)
1318 return NULL;
1319
1320 conn = kzalloc(sizeof(struct l2cap_conn), GFP_ATOMIC);
1321 if (!conn) {
1322 hci_chan_del(hchan);
1323 return NULL;
1324 }
1325
1326 hcon->l2cap_data = conn;
1327 conn->hcon = hcon;
1328 conn->hchan = hchan;
1329
1330 BT_DBG("hcon %p conn %p hchan %p", hcon, conn, hchan);
1331
1332 if (hcon->hdev->le_mtu && hcon->type == LE_LINK)
1333 conn->mtu = hcon->hdev->le_mtu;
1334 else
1335 conn->mtu = hcon->hdev->acl_mtu;
1336
1337 conn->src = &hcon->hdev->bdaddr;
1338 conn->dst = &hcon->dst;
1339
1340 conn->feat_mask = 0;
1341
1342 spin_lock_init(&conn->lock);
1343 mutex_init(&conn->chan_lock);
1344
1345 INIT_LIST_HEAD(&conn->chan_l);
1346
1347 if (hcon->type == LE_LINK)
1348 INIT_DELAYED_WORK(&conn->security_timer, security_timeout);
1349 else
1350 INIT_DELAYED_WORK(&conn->info_timer, l2cap_info_timeout);
1351
1352 conn->disc_reason = HCI_ERROR_REMOTE_USER_TERM;
1353
1354 return conn;
1355}
1356
1357/* ---- Socket interface ---- */
1358
1359/* Find socket with psm and source / destination bdaddr.
1360 * Returns closest match.
1361 */
1362static struct l2cap_chan *l2cap_global_chan_by_psm(int state, __le16 psm,
1363 bdaddr_t *src,
1364 bdaddr_t *dst)
1365{
1366 struct l2cap_chan *c, *c1 = NULL;
1367
1368 read_lock(&chan_list_lock);
1369
1370 list_for_each_entry(c, &chan_list, global_l) {
1371 struct sock *sk = c->sk;
1372
1373 if (state && c->state != state)
1374 continue;
1375
1376 if (c->psm == psm) {
1377 int src_match, dst_match;
1378 int src_any, dst_any;
1379
1380 /* Exact match. */
1381 src_match = !bacmp(&bt_sk(sk)->src, src);
1382 dst_match = !bacmp(&bt_sk(sk)->dst, dst);
1383 if (src_match && dst_match) {
1384 read_unlock(&chan_list_lock);
1385 return c;
1386 }
1387
1388 /* Closest match */
1389 src_any = !bacmp(&bt_sk(sk)->src, BDADDR_ANY);
1390 dst_any = !bacmp(&bt_sk(sk)->dst, BDADDR_ANY);
1391 if ((src_match && dst_any) || (src_any && dst_match) ||
1392 (src_any && dst_any))
1393 c1 = c;
1394 }
1395 }
1396
1397 read_unlock(&chan_list_lock);
1398
1399 return c1;
1400}
1401
1402int l2cap_chan_connect(struct l2cap_chan *chan, __le16 psm, u16 cid,
1403 bdaddr_t *dst, u8 dst_type)
1404{
1405 struct sock *sk = chan->sk;
1406 bdaddr_t *src = &bt_sk(sk)->src;
1407 struct l2cap_conn *conn;
1408 struct hci_conn *hcon;
1409 struct hci_dev *hdev;
1410 __u8 auth_type;
1411 int err;
1412
1413 BT_DBG("%s -> %s (type %u) psm 0x%2.2x", batostr(src), batostr(dst),
1414 dst_type, __le16_to_cpu(chan->psm));
1415
1416 hdev = hci_get_route(dst, src);
1417 if (!hdev)
1418 return -EHOSTUNREACH;
1419
1420 hci_dev_lock(hdev);
1421
1422 l2cap_chan_lock(chan);
1423
1424 /* PSM must be odd and lsb of upper byte must be 0 */
1425 if ((__le16_to_cpu(psm) & 0x0101) != 0x0001 && !cid &&
1426 chan->chan_type != L2CAP_CHAN_RAW) {
1427 err = -EINVAL;
1428 goto done;
1429 }
1430
1431 if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED && !(psm || cid)) {
1432 err = -EINVAL;
1433 goto done;
1434 }
1435
1436 switch (chan->mode) {
1437 case L2CAP_MODE_BASIC:
1438 break;
1439 case L2CAP_MODE_ERTM:
1440 case L2CAP_MODE_STREAMING:
1441 if (!disable_ertm)
1442 break;
1443 /* fall through */
1444 default:
1445 err = -ENOTSUPP;
1446 goto done;
1447 }
1448
1449 lock_sock(sk);
1450
1451 switch (sk->sk_state) {
1452 case BT_CONNECT:
1453 case BT_CONNECT2:
1454 case BT_CONFIG:
1455 /* Already connecting */
1456 err = 0;
1457 release_sock(sk);
1458 goto done;
1459
1460 case BT_CONNECTED:
1461 /* Already connected */
1462 err = -EISCONN;
1463 release_sock(sk);
1464 goto done;
1465
1466 case BT_OPEN:
1467 case BT_BOUND:
1468 /* Can connect */
1469 break;
1470
1471 default:
1472 err = -EBADFD;
1473 release_sock(sk);
1474 goto done;
1475 }
1476
1477 /* Set destination address and psm */
1478 bacpy(&bt_sk(sk)->dst, dst);
1479
1480 release_sock(sk);
1481
1482 chan->psm = psm;
1483 chan->dcid = cid;
1484
1485 auth_type = l2cap_get_auth_type(chan);
1486
1487 if (chan->dcid == L2CAP_CID_LE_DATA)
1488 hcon = hci_connect(hdev, LE_LINK, dst, dst_type,
1489 chan->sec_level, auth_type);
1490 else
1491 hcon = hci_connect(hdev, ACL_LINK, dst, dst_type,
1492 chan->sec_level, auth_type);
1493
1494 if (IS_ERR(hcon)) {
1495 err = PTR_ERR(hcon);
1496 goto done;
1497 }
1498
1499 conn = l2cap_conn_add(hcon, 0);
1500 if (!conn) {
1501 hci_conn_put(hcon);
1502 err = -ENOMEM;
1503 goto done;
1504 }
1505
1506 if (hcon->type == LE_LINK) {
1507 err = 0;
1508
1509 if (!list_empty(&conn->chan_l)) {
1510 err = -EBUSY;
1511 hci_conn_put(hcon);
1512 }
1513
1514 if (err)
1515 goto done;
1516 }
1517
1518 /* Update source addr of the socket */
1519 bacpy(src, conn->src);
1520
1521 l2cap_chan_unlock(chan);
1522 l2cap_chan_add(conn, chan);
1523 l2cap_chan_lock(chan);
1524
1525 l2cap_state_change(chan, BT_CONNECT);
1526 __set_chan_timer(chan, sk->sk_sndtimeo);
1527
1528 if (hcon->state == BT_CONNECTED) {
1529 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
1530 __clear_chan_timer(chan);
1531 if (l2cap_chan_check_security(chan))
1532 l2cap_state_change(chan, BT_CONNECTED);
1533 } else
1534 l2cap_do_start(chan);
1535 }
1536
1537 err = 0;
1538
1539done:
1540 l2cap_chan_unlock(chan);
1541 hci_dev_unlock(hdev);
1542 hci_dev_put(hdev);
1543 return err;
1544}
1545
1546int __l2cap_wait_ack(struct sock *sk)
1547{
1548 struct l2cap_chan *chan = l2cap_pi(sk)->chan;
1549 DECLARE_WAITQUEUE(wait, current);
1550 int err = 0;
1551 int timeo = HZ/5;
1552
1553 add_wait_queue(sk_sleep(sk), &wait);
1554 set_current_state(TASK_INTERRUPTIBLE);
1555 while (chan->unacked_frames > 0 && chan->conn) {
1556 if (!timeo)
1557 timeo = HZ/5;
1558
1559 if (signal_pending(current)) {
1560 err = sock_intr_errno(timeo);
1561 break;
1562 }
1563
1564 release_sock(sk);
1565 timeo = schedule_timeout(timeo);
1566 lock_sock(sk);
1567 set_current_state(TASK_INTERRUPTIBLE);
1568
1569 err = sock_error(sk);
1570 if (err)
1571 break;
1572 }
1573 set_current_state(TASK_RUNNING);
1574 remove_wait_queue(sk_sleep(sk), &wait);
1575 return err;
1576}
1577
1578static void l2cap_monitor_timeout(struct work_struct *work)
1579{
1580 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
1581 monitor_timer.work);
1582
1583 BT_DBG("chan %p", chan);
1584
1585 l2cap_chan_lock(chan);
1586
1587 if (chan->retry_count >= chan->remote_max_tx) {
1588 l2cap_send_disconn_req(chan->conn, chan, ECONNABORTED);
1589 l2cap_chan_unlock(chan);
1590 l2cap_chan_put(chan);
1591 return;
1592 }
1593
1594 chan->retry_count++;
1595 __set_monitor_timer(chan);
1596
1597 l2cap_send_rr_or_rnr(chan, L2CAP_CTRL_POLL);
1598 l2cap_chan_unlock(chan);
1599 l2cap_chan_put(chan);
1600}
1601
1602static void l2cap_retrans_timeout(struct work_struct *work)
1603{
1604 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
1605 retrans_timer.work);
1606
1607 BT_DBG("chan %p", chan);
1608
1609 l2cap_chan_lock(chan);
1610
1611 chan->retry_count = 1;
1612 __set_monitor_timer(chan);
1613
1614 set_bit(CONN_WAIT_F, &chan->conn_state);
1615
1616 l2cap_send_rr_or_rnr(chan, L2CAP_CTRL_POLL);
1617
1618 l2cap_chan_unlock(chan);
1619 l2cap_chan_put(chan);
1620}
1621
1622static void l2cap_drop_acked_frames(struct l2cap_chan *chan)
1623{
1624 struct sk_buff *skb;
1625
1626 while ((skb = skb_peek(&chan->tx_q)) &&
1627 chan->unacked_frames) {
1628 if (bt_cb(skb)->control.txseq == chan->expected_ack_seq)
1629 break;
1630
1631 skb = skb_dequeue(&chan->tx_q);
1632 kfree_skb(skb);
1633
1634 chan->unacked_frames--;
1635 }
1636
1637 if (!chan->unacked_frames)
1638 __clear_retrans_timer(chan);
1639}
1640
1641static void l2cap_streaming_send(struct l2cap_chan *chan)
1642{
1643 struct sk_buff *skb;
1644 u32 control;
1645 u16 fcs;
1646
1647 while ((skb = skb_dequeue(&chan->tx_q))) {
1648 control = __get_control(chan, skb->data + L2CAP_HDR_SIZE);
1649 control |= __set_txseq(chan, chan->next_tx_seq);
1650 control |= __set_ctrl_sar(chan, bt_cb(skb)->control.sar);
1651 __put_control(chan, control, skb->data + L2CAP_HDR_SIZE);
1652
1653 if (chan->fcs == L2CAP_FCS_CRC16) {
1654 fcs = crc16(0, (u8 *)skb->data,
1655 skb->len - L2CAP_FCS_SIZE);
1656 put_unaligned_le16(fcs,
1657 skb->data + skb->len - L2CAP_FCS_SIZE);
1658 }
1659
1660 l2cap_do_send(chan, skb);
1661
1662 chan->next_tx_seq = __next_seq(chan, chan->next_tx_seq);
1663 }
1664}
1665
1666static void l2cap_retransmit_one_frame(struct l2cap_chan *chan, u16 tx_seq)
1667{
1668 struct sk_buff *skb, *tx_skb;
1669 u16 fcs;
1670 u32 control;
1671
1672 skb = skb_peek(&chan->tx_q);
1673 if (!skb)
1674 return;
1675
1676 while (bt_cb(skb)->control.txseq != tx_seq) {
1677 if (skb_queue_is_last(&chan->tx_q, skb))
1678 return;
1679
1680 skb = skb_queue_next(&chan->tx_q, skb);
1681 }
1682
1683 if (bt_cb(skb)->control.retries == chan->remote_max_tx &&
1684 chan->remote_max_tx) {
1685 l2cap_send_disconn_req(chan->conn, chan, ECONNABORTED);
1686 return;
1687 }
1688
1689 tx_skb = skb_clone(skb, GFP_ATOMIC);
1690 bt_cb(skb)->control.retries++;
1691
1692 control = __get_control(chan, tx_skb->data + L2CAP_HDR_SIZE);
1693 control &= __get_sar_mask(chan);
1694
1695 if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state))
1696 control |= __set_ctrl_final(chan);
1697
1698 control |= __set_reqseq(chan, chan->buffer_seq);
1699 control |= __set_txseq(chan, tx_seq);
1700
1701 __put_control(chan, control, tx_skb->data + L2CAP_HDR_SIZE);
1702
1703 if (chan->fcs == L2CAP_FCS_CRC16) {
1704 fcs = crc16(0, (u8 *)tx_skb->data,
1705 tx_skb->len - L2CAP_FCS_SIZE);
1706 put_unaligned_le16(fcs,
1707 tx_skb->data + tx_skb->len - L2CAP_FCS_SIZE);
1708 }
1709
1710 l2cap_do_send(chan, tx_skb);
1711}
1712
1713static int l2cap_ertm_send(struct l2cap_chan *chan)
1714{
1715 struct sk_buff *skb, *tx_skb;
1716 u16 fcs;
1717 u32 control;
1718 int nsent = 0;
1719
1720 if (chan->state != BT_CONNECTED)
1721 return -ENOTCONN;
1722
1723 if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state))
1724 return 0;
1725
1726 while ((skb = chan->tx_send_head) && (!l2cap_tx_window_full(chan))) {
1727
1728 if (bt_cb(skb)->control.retries == chan->remote_max_tx &&
1729 chan->remote_max_tx) {
1730 l2cap_send_disconn_req(chan->conn, chan, ECONNABORTED);
1731 break;
1732 }
1733
1734 tx_skb = skb_clone(skb, GFP_ATOMIC);
1735
1736 bt_cb(skb)->control.retries++;
1737
1738 control = __get_control(chan, tx_skb->data + L2CAP_HDR_SIZE);
1739 control &= __get_sar_mask(chan);
1740
1741 if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state))
1742 control |= __set_ctrl_final(chan);
1743
1744 control |= __set_reqseq(chan, chan->buffer_seq);
1745 control |= __set_txseq(chan, chan->next_tx_seq);
1746 control |= __set_ctrl_sar(chan, bt_cb(skb)->control.sar);
1747
1748 __put_control(chan, control, tx_skb->data + L2CAP_HDR_SIZE);
1749
1750 if (chan->fcs == L2CAP_FCS_CRC16) {
1751 fcs = crc16(0, (u8 *)skb->data,
1752 tx_skb->len - L2CAP_FCS_SIZE);
1753 put_unaligned_le16(fcs, skb->data +
1754 tx_skb->len - L2CAP_FCS_SIZE);
1755 }
1756
1757 l2cap_do_send(chan, tx_skb);
1758
1759 __set_retrans_timer(chan);
1760
1761 bt_cb(skb)->control.txseq = chan->next_tx_seq;
1762
1763 chan->next_tx_seq = __next_seq(chan, chan->next_tx_seq);
1764
1765 if (bt_cb(skb)->control.retries == 1) {
1766 chan->unacked_frames++;
1767
1768 if (!nsent++)
1769 __clear_ack_timer(chan);
1770 }
1771
1772 chan->frames_sent++;
1773
1774 if (skb_queue_is_last(&chan->tx_q, skb))
1775 chan->tx_send_head = NULL;
1776 else
1777 chan->tx_send_head = skb_queue_next(&chan->tx_q, skb);
1778 }
1779
1780 return nsent;
1781}
1782
1783static int l2cap_retransmit_frames(struct l2cap_chan *chan)
1784{
1785 int ret;
1786
1787 if (!skb_queue_empty(&chan->tx_q))
1788 chan->tx_send_head = chan->tx_q.next;
1789
1790 chan->next_tx_seq = chan->expected_ack_seq;
1791 ret = l2cap_ertm_send(chan);
1792 return ret;
1793}
1794
1795static void __l2cap_send_ack(struct l2cap_chan *chan)
1796{
1797 u32 control = 0;
1798
1799 control |= __set_reqseq(chan, chan->buffer_seq);
1800
1801 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
1802 control |= __set_ctrl_super(chan, L2CAP_SUPER_RNR);
1803 set_bit(CONN_RNR_SENT, &chan->conn_state);
1804 l2cap_send_sframe(chan, control);
1805 return;
1806 }
1807
1808 if (l2cap_ertm_send(chan) > 0)
1809 return;
1810
1811 control |= __set_ctrl_super(chan, L2CAP_SUPER_RR);
1812 l2cap_send_sframe(chan, control);
1813}
1814
1815static void l2cap_send_ack(struct l2cap_chan *chan)
1816{
1817 __clear_ack_timer(chan);
1818 __l2cap_send_ack(chan);
1819}
1820
1821static void l2cap_send_srejtail(struct l2cap_chan *chan)
1822{
1823 struct srej_list *tail;
1824 u32 control;
1825
1826 control = __set_ctrl_super(chan, L2CAP_SUPER_SREJ);
1827 control |= __set_ctrl_final(chan);
1828
1829 tail = list_entry((&chan->srej_l)->prev, struct srej_list, list);
1830 control |= __set_reqseq(chan, tail->tx_seq);
1831
1832 l2cap_send_sframe(chan, control);
1833}
1834
1835static inline int l2cap_skbuff_fromiovec(struct l2cap_chan *chan,
1836 struct msghdr *msg, int len,
1837 int count, struct sk_buff *skb)
1838{
1839 struct l2cap_conn *conn = chan->conn;
1840 struct sk_buff **frag;
1841 int sent = 0;
1842
1843 if (memcpy_fromiovec(skb_put(skb, count), msg->msg_iov, count))
1844 return -EFAULT;
1845
1846 sent += count;
1847 len -= count;
1848
1849 /* Continuation fragments (no L2CAP header) */
1850 frag = &skb_shinfo(skb)->frag_list;
1851 while (len) {
1852 struct sk_buff *tmp;
1853
1854 count = min_t(unsigned int, conn->mtu, len);
1855
1856 tmp = chan->ops->alloc_skb(chan, count,
1857 msg->msg_flags & MSG_DONTWAIT);
1858 if (IS_ERR(tmp))
1859 return PTR_ERR(tmp);
1860
1861 *frag = tmp;
1862
1863 if (memcpy_fromiovec(skb_put(*frag, count), msg->msg_iov, count))
1864 return -EFAULT;
1865
1866 (*frag)->priority = skb->priority;
1867
1868 sent += count;
1869 len -= count;
1870
1871 skb->len += (*frag)->len;
1872 skb->data_len += (*frag)->len;
1873
1874 frag = &(*frag)->next;
1875 }
1876
1877 return sent;
1878}
1879
1880static struct sk_buff *l2cap_create_connless_pdu(struct l2cap_chan *chan,
1881 struct msghdr *msg, size_t len,
1882 u32 priority)
1883{
1884 struct l2cap_conn *conn = chan->conn;
1885 struct sk_buff *skb;
1886 int err, count, hlen = L2CAP_HDR_SIZE + L2CAP_PSMLEN_SIZE;
1887 struct l2cap_hdr *lh;
1888
1889 BT_DBG("chan %p len %d priority %u", chan, (int)len, priority);
1890
1891 count = min_t(unsigned int, (conn->mtu - hlen), len);
1892
1893 skb = chan->ops->alloc_skb(chan, count + hlen,
1894 msg->msg_flags & MSG_DONTWAIT);
1895 if (IS_ERR(skb))
1896 return skb;
1897
1898 skb->priority = priority;
1899
1900 /* Create L2CAP header */
1901 lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
1902 lh->cid = cpu_to_le16(chan->dcid);
1903 lh->len = cpu_to_le16(len + L2CAP_PSMLEN_SIZE);
1904 put_unaligned(chan->psm, skb_put(skb, L2CAP_PSMLEN_SIZE));
1905
1906 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
1907 if (unlikely(err < 0)) {
1908 kfree_skb(skb);
1909 return ERR_PTR(err);
1910 }
1911 return skb;
1912}
1913
1914static struct sk_buff *l2cap_create_basic_pdu(struct l2cap_chan *chan,
1915 struct msghdr *msg, size_t len,
1916 u32 priority)
1917{
1918 struct l2cap_conn *conn = chan->conn;
1919 struct sk_buff *skb;
1920 int err, count;
1921 struct l2cap_hdr *lh;
1922
1923 BT_DBG("chan %p len %d", chan, (int)len);
1924
1925 count = min_t(unsigned int, (conn->mtu - L2CAP_HDR_SIZE), len);
1926
1927 skb = chan->ops->alloc_skb(chan, count + L2CAP_HDR_SIZE,
1928 msg->msg_flags & MSG_DONTWAIT);
1929 if (IS_ERR(skb))
1930 return skb;
1931
1932 skb->priority = priority;
1933
1934 /* Create L2CAP header */
1935 lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
1936 lh->cid = cpu_to_le16(chan->dcid);
1937 lh->len = cpu_to_le16(len);
1938
1939 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
1940 if (unlikely(err < 0)) {
1941 kfree_skb(skb);
1942 return ERR_PTR(err);
1943 }
1944 return skb;
1945}
1946
1947static struct sk_buff *l2cap_create_iframe_pdu(struct l2cap_chan *chan,
1948 struct msghdr *msg, size_t len,
1949 u16 sdulen)
1950{
1951 struct l2cap_conn *conn = chan->conn;
1952 struct sk_buff *skb;
1953 int err, count, hlen;
1954 struct l2cap_hdr *lh;
1955
1956 BT_DBG("chan %p len %d", chan, (int)len);
1957
1958 if (!conn)
1959 return ERR_PTR(-ENOTCONN);
1960
1961 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
1962 hlen = L2CAP_EXT_HDR_SIZE;
1963 else
1964 hlen = L2CAP_ENH_HDR_SIZE;
1965
1966 if (sdulen)
1967 hlen += L2CAP_SDULEN_SIZE;
1968
1969 if (chan->fcs == L2CAP_FCS_CRC16)
1970 hlen += L2CAP_FCS_SIZE;
1971
1972 count = min_t(unsigned int, (conn->mtu - hlen), len);
1973
1974 skb = chan->ops->alloc_skb(chan, count + hlen,
1975 msg->msg_flags & MSG_DONTWAIT);
1976 if (IS_ERR(skb))
1977 return skb;
1978
1979 /* Create L2CAP header */
1980 lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
1981 lh->cid = cpu_to_le16(chan->dcid);
1982 lh->len = cpu_to_le16(len + (hlen - L2CAP_HDR_SIZE));
1983
1984 __put_control(chan, 0, skb_put(skb, __ctrl_size(chan)));
1985
1986 if (sdulen)
1987 put_unaligned_le16(sdulen, skb_put(skb, L2CAP_SDULEN_SIZE));
1988
1989 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
1990 if (unlikely(err < 0)) {
1991 kfree_skb(skb);
1992 return ERR_PTR(err);
1993 }
1994
1995 if (chan->fcs == L2CAP_FCS_CRC16)
1996 put_unaligned_le16(0, skb_put(skb, L2CAP_FCS_SIZE));
1997
1998 bt_cb(skb)->control.retries = 0;
1999 return skb;
2000}
2001
2002static int l2cap_segment_sdu(struct l2cap_chan *chan,
2003 struct sk_buff_head *seg_queue,
2004 struct msghdr *msg, size_t len)
2005{
2006 struct sk_buff *skb;
2007 u16 sdu_len;
2008 size_t pdu_len;
2009 int err = 0;
2010 u8 sar;
2011
2012 BT_DBG("chan %p, msg %p, len %d", chan, msg, (int)len);
2013
2014 /* It is critical that ERTM PDUs fit in a single HCI fragment,
2015 * so fragmented skbs are not used. The HCI layer's handling
2016 * of fragmented skbs is not compatible with ERTM's queueing.
2017 */
2018
2019 /* PDU size is derived from the HCI MTU */
2020 pdu_len = chan->conn->mtu;
2021
2022 pdu_len = min_t(size_t, pdu_len, L2CAP_BREDR_MAX_PAYLOAD);
2023
2024 /* Adjust for largest possible L2CAP overhead. */
2025 pdu_len -= L2CAP_EXT_HDR_SIZE + L2CAP_FCS_SIZE;
2026
2027 /* Remote device may have requested smaller PDUs */
2028 pdu_len = min_t(size_t, pdu_len, chan->remote_mps);
2029
2030 if (len <= pdu_len) {
2031 sar = L2CAP_SAR_UNSEGMENTED;
2032 sdu_len = 0;
2033 pdu_len = len;
2034 } else {
2035 sar = L2CAP_SAR_START;
2036 sdu_len = len;
2037 pdu_len -= L2CAP_SDULEN_SIZE;
2038 }
2039
2040 while (len > 0) {
2041 skb = l2cap_create_iframe_pdu(chan, msg, pdu_len, sdu_len);
2042
2043 if (IS_ERR(skb)) {
2044 __skb_queue_purge(seg_queue);
2045 return PTR_ERR(skb);
2046 }
2047
2048 bt_cb(skb)->control.sar = sar;
2049 __skb_queue_tail(seg_queue, skb);
2050
2051 len -= pdu_len;
2052 if (sdu_len) {
2053 sdu_len = 0;
2054 pdu_len += L2CAP_SDULEN_SIZE;
2055 }
2056
2057 if (len <= pdu_len) {
2058 sar = L2CAP_SAR_END;
2059 pdu_len = len;
2060 } else {
2061 sar = L2CAP_SAR_CONTINUE;
2062 }
2063 }
2064
2065 return err;
2066}
2067
2068int l2cap_chan_send(struct l2cap_chan *chan, struct msghdr *msg, size_t len,
2069 u32 priority)
2070{
2071 struct sk_buff *skb;
2072 int err;
2073 struct sk_buff_head seg_queue;
2074
2075 /* Connectionless channel */
2076 if (chan->chan_type == L2CAP_CHAN_CONN_LESS) {
2077 skb = l2cap_create_connless_pdu(chan, msg, len, priority);
2078 if (IS_ERR(skb))
2079 return PTR_ERR(skb);
2080
2081 l2cap_do_send(chan, skb);
2082 return len;
2083 }
2084
2085 switch (chan->mode) {
2086 case L2CAP_MODE_BASIC:
2087 /* Check outgoing MTU */
2088 if (len > chan->omtu)
2089 return -EMSGSIZE;
2090
2091 /* Create a basic PDU */
2092 skb = l2cap_create_basic_pdu(chan, msg, len, priority);
2093 if (IS_ERR(skb))
2094 return PTR_ERR(skb);
2095
2096 l2cap_do_send(chan, skb);
2097 err = len;
2098 break;
2099
2100 case L2CAP_MODE_ERTM:
2101 case L2CAP_MODE_STREAMING:
2102 /* Check outgoing MTU */
2103 if (len > chan->omtu) {
2104 err = -EMSGSIZE;
2105 break;
2106 }
2107
2108 __skb_queue_head_init(&seg_queue);
2109
2110 /* Do segmentation before calling in to the state machine,
2111 * since it's possible to block while waiting for memory
2112 * allocation.
2113 */
2114 err = l2cap_segment_sdu(chan, &seg_queue, msg, len);
2115
2116 /* The channel could have been closed while segmenting,
2117 * check that it is still connected.
2118 */
2119 if (chan->state != BT_CONNECTED) {
2120 __skb_queue_purge(&seg_queue);
2121 err = -ENOTCONN;
2122 }
2123
2124 if (err)
2125 break;
2126
2127 if (chan->mode == L2CAP_MODE_ERTM && chan->tx_send_head == NULL)
2128 chan->tx_send_head = seg_queue.next;
2129 skb_queue_splice_tail_init(&seg_queue, &chan->tx_q);
2130
2131 if (chan->mode == L2CAP_MODE_ERTM)
2132 err = l2cap_ertm_send(chan);
2133 else
2134 l2cap_streaming_send(chan);
2135
2136 if (err >= 0)
2137 err = len;
2138
2139 /* If the skbs were not queued for sending, they'll still be in
2140 * seg_queue and need to be purged.
2141 */
2142 __skb_queue_purge(&seg_queue);
2143 break;
2144
2145 default:
2146 BT_DBG("bad state %1.1x", chan->mode);
2147 err = -EBADFD;
2148 }
2149
2150 return err;
2151}
2152
2153/* Copy frame to all raw sockets on that connection */
2154static void l2cap_raw_recv(struct l2cap_conn *conn, struct sk_buff *skb)
2155{
2156 struct sk_buff *nskb;
2157 struct l2cap_chan *chan;
2158
2159 BT_DBG("conn %p", conn);
2160
2161 mutex_lock(&conn->chan_lock);
2162
2163 list_for_each_entry(chan, &conn->chan_l, list) {
2164 struct sock *sk = chan->sk;
2165 if (chan->chan_type != L2CAP_CHAN_RAW)
2166 continue;
2167
2168 /* Don't send frame to the socket it came from */
2169 if (skb->sk == sk)
2170 continue;
2171 nskb = skb_clone(skb, GFP_ATOMIC);
2172 if (!nskb)
2173 continue;
2174
2175 if (chan->ops->recv(chan->data, nskb))
2176 kfree_skb(nskb);
2177 }
2178
2179 mutex_unlock(&conn->chan_lock);
2180}
2181
2182/* ---- L2CAP signalling commands ---- */
2183static struct sk_buff *l2cap_build_cmd(struct l2cap_conn *conn,
2184 u8 code, u8 ident, u16 dlen, void *data)
2185{
2186 struct sk_buff *skb, **frag;
2187 struct l2cap_cmd_hdr *cmd;
2188 struct l2cap_hdr *lh;
2189 int len, count;
2190
2191 BT_DBG("conn %p, code 0x%2.2x, ident 0x%2.2x, len %d",
2192 conn, code, ident, dlen);
2193
2194 len = L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE + dlen;
2195 count = min_t(unsigned int, conn->mtu, len);
2196
2197 skb = bt_skb_alloc(count, GFP_ATOMIC);
2198 if (!skb)
2199 return NULL;
2200
2201 lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
2202 lh->len = cpu_to_le16(L2CAP_CMD_HDR_SIZE + dlen);
2203
2204 if (conn->hcon->type == LE_LINK)
2205 lh->cid = cpu_to_le16(L2CAP_CID_LE_SIGNALING);
2206 else
2207 lh->cid = cpu_to_le16(L2CAP_CID_SIGNALING);
2208
2209 cmd = (struct l2cap_cmd_hdr *) skb_put(skb, L2CAP_CMD_HDR_SIZE);
2210 cmd->code = code;
2211 cmd->ident = ident;
2212 cmd->len = cpu_to_le16(dlen);
2213
2214 if (dlen) {
2215 count -= L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE;
2216 memcpy(skb_put(skb, count), data, count);
2217 data += count;
2218 }
2219
2220 len -= skb->len;
2221
2222 /* Continuation fragments (no L2CAP header) */
2223 frag = &skb_shinfo(skb)->frag_list;
2224 while (len) {
2225 count = min_t(unsigned int, conn->mtu, len);
2226
2227 *frag = bt_skb_alloc(count, GFP_ATOMIC);
2228 if (!*frag)
2229 goto fail;
2230
2231 memcpy(skb_put(*frag, count), data, count);
2232
2233 len -= count;
2234 data += count;
2235
2236 frag = &(*frag)->next;
2237 }
2238
2239 return skb;
2240
2241fail:
2242 kfree_skb(skb);
2243 return NULL;
2244}
2245
2246static inline int l2cap_get_conf_opt(void **ptr, int *type, int *olen, unsigned long *val)
2247{
2248 struct l2cap_conf_opt *opt = *ptr;
2249 int len;
2250
2251 len = L2CAP_CONF_OPT_SIZE + opt->len;
2252 *ptr += len;
2253
2254 *type = opt->type;
2255 *olen = opt->len;
2256
2257 switch (opt->len) {
2258 case 1:
2259 *val = *((u8 *) opt->val);
2260 break;
2261
2262 case 2:
2263 *val = get_unaligned_le16(opt->val);
2264 break;
2265
2266 case 4:
2267 *val = get_unaligned_le32(opt->val);
2268 break;
2269
2270 default:
2271 *val = (unsigned long) opt->val;
2272 break;
2273 }
2274
2275 BT_DBG("type 0x%2.2x len %d val 0x%lx", *type, opt->len, *val);
2276 return len;
2277}
2278
2279static void l2cap_add_conf_opt(void **ptr, u8 type, u8 len, unsigned long val)
2280{
2281 struct l2cap_conf_opt *opt = *ptr;
2282
2283 BT_DBG("type 0x%2.2x len %d val 0x%lx", type, len, val);
2284
2285 opt->type = type;
2286 opt->len = len;
2287
2288 switch (len) {
2289 case 1:
2290 *((u8 *) opt->val) = val;
2291 break;
2292
2293 case 2:
2294 put_unaligned_le16(val, opt->val);
2295 break;
2296
2297 case 4:
2298 put_unaligned_le32(val, opt->val);
2299 break;
2300
2301 default:
2302 memcpy(opt->val, (void *) val, len);
2303 break;
2304 }
2305
2306 *ptr += L2CAP_CONF_OPT_SIZE + len;
2307}
2308
2309static void l2cap_add_opt_efs(void **ptr, struct l2cap_chan *chan)
2310{
2311 struct l2cap_conf_efs efs;
2312
2313 switch (chan->mode) {
2314 case L2CAP_MODE_ERTM:
2315 efs.id = chan->local_id;
2316 efs.stype = chan->local_stype;
2317 efs.msdu = cpu_to_le16(chan->local_msdu);
2318 efs.sdu_itime = cpu_to_le32(chan->local_sdu_itime);
2319 efs.acc_lat = cpu_to_le32(L2CAP_DEFAULT_ACC_LAT);
2320 efs.flush_to = cpu_to_le32(L2CAP_DEFAULT_FLUSH_TO);
2321 break;
2322
2323 case L2CAP_MODE_STREAMING:
2324 efs.id = 1;
2325 efs.stype = L2CAP_SERV_BESTEFFORT;
2326 efs.msdu = cpu_to_le16(chan->local_msdu);
2327 efs.sdu_itime = cpu_to_le32(chan->local_sdu_itime);
2328 efs.acc_lat = 0;
2329 efs.flush_to = 0;
2330 break;
2331
2332 default:
2333 return;
2334 }
2335
2336 l2cap_add_conf_opt(ptr, L2CAP_CONF_EFS, sizeof(efs),
2337 (unsigned long) &efs);
2338}
2339
2340static void l2cap_ack_timeout(struct work_struct *work)
2341{
2342 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
2343 ack_timer.work);
2344
2345 BT_DBG("chan %p", chan);
2346
2347 l2cap_chan_lock(chan);
2348
2349 __l2cap_send_ack(chan);
2350
2351 l2cap_chan_unlock(chan);
2352
2353 l2cap_chan_put(chan);
2354}
2355
2356static inline int l2cap_ertm_init(struct l2cap_chan *chan)
2357{
2358 int err;
2359
2360 chan->next_tx_seq = 0;
2361 chan->expected_tx_seq = 0;
2362 chan->expected_ack_seq = 0;
2363 chan->unacked_frames = 0;
2364 chan->buffer_seq = 0;
2365 chan->num_acked = 0;
2366 chan->frames_sent = 0;
2367 chan->last_acked_seq = 0;
2368 chan->sdu = NULL;
2369 chan->sdu_last_frag = NULL;
2370 chan->sdu_len = 0;
2371
2372 skb_queue_head_init(&chan->tx_q);
2373
2374 if (chan->mode != L2CAP_MODE_ERTM)
2375 return 0;
2376
2377 chan->rx_state = L2CAP_RX_STATE_RECV;
2378 chan->tx_state = L2CAP_TX_STATE_XMIT;
2379
2380 INIT_DELAYED_WORK(&chan->retrans_timer, l2cap_retrans_timeout);
2381 INIT_DELAYED_WORK(&chan->monitor_timer, l2cap_monitor_timeout);
2382 INIT_DELAYED_WORK(&chan->ack_timer, l2cap_ack_timeout);
2383
2384 skb_queue_head_init(&chan->srej_q);
2385
2386 INIT_LIST_HEAD(&chan->srej_l);
2387 err = l2cap_seq_list_init(&chan->srej_list, chan->tx_win);
2388 if (err < 0)
2389 return err;
2390
2391 return l2cap_seq_list_init(&chan->retrans_list, chan->remote_tx_win);
2392}
2393
2394static inline __u8 l2cap_select_mode(__u8 mode, __u16 remote_feat_mask)
2395{
2396 switch (mode) {
2397 case L2CAP_MODE_STREAMING:
2398 case L2CAP_MODE_ERTM:
2399 if (l2cap_mode_supported(mode, remote_feat_mask))
2400 return mode;
2401 /* fall through */
2402 default:
2403 return L2CAP_MODE_BASIC;
2404 }
2405}
2406
2407static inline bool __l2cap_ews_supported(struct l2cap_chan *chan)
2408{
2409 return enable_hs && chan->conn->feat_mask & L2CAP_FEAT_EXT_WINDOW;
2410}
2411
2412static inline bool __l2cap_efs_supported(struct l2cap_chan *chan)
2413{
2414 return enable_hs && chan->conn->feat_mask & L2CAP_FEAT_EXT_FLOW;
2415}
2416
2417static inline void l2cap_txwin_setup(struct l2cap_chan *chan)
2418{
2419 if (chan->tx_win > L2CAP_DEFAULT_TX_WINDOW &&
2420 __l2cap_ews_supported(chan)) {
2421 /* use extended control field */
2422 set_bit(FLAG_EXT_CTRL, &chan->flags);
2423 chan->tx_win_max = L2CAP_DEFAULT_EXT_WINDOW;
2424 } else {
2425 chan->tx_win = min_t(u16, chan->tx_win,
2426 L2CAP_DEFAULT_TX_WINDOW);
2427 chan->tx_win_max = L2CAP_DEFAULT_TX_WINDOW;
2428 }
2429}
2430
2431static int l2cap_build_conf_req(struct l2cap_chan *chan, void *data)
2432{
2433 struct l2cap_conf_req *req = data;
2434 struct l2cap_conf_rfc rfc = { .mode = chan->mode };
2435 void *ptr = req->data;
2436 u16 size;
2437
2438 BT_DBG("chan %p", chan);
2439
2440 if (chan->num_conf_req || chan->num_conf_rsp)
2441 goto done;
2442
2443 switch (chan->mode) {
2444 case L2CAP_MODE_STREAMING:
2445 case L2CAP_MODE_ERTM:
2446 if (test_bit(CONF_STATE2_DEVICE, &chan->conf_state))
2447 break;
2448
2449 if (__l2cap_efs_supported(chan))
2450 set_bit(FLAG_EFS_ENABLE, &chan->flags);
2451
2452 /* fall through */
2453 default:
2454 chan->mode = l2cap_select_mode(rfc.mode, chan->conn->feat_mask);
2455 break;
2456 }
2457
2458done:
2459 if (chan->imtu != L2CAP_DEFAULT_MTU)
2460 l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->imtu);
2461
2462 switch (chan->mode) {
2463 case L2CAP_MODE_BASIC:
2464 if (!(chan->conn->feat_mask & L2CAP_FEAT_ERTM) &&
2465 !(chan->conn->feat_mask & L2CAP_FEAT_STREAMING))
2466 break;
2467
2468 rfc.mode = L2CAP_MODE_BASIC;
2469 rfc.txwin_size = 0;
2470 rfc.max_transmit = 0;
2471 rfc.retrans_timeout = 0;
2472 rfc.monitor_timeout = 0;
2473 rfc.max_pdu_size = 0;
2474
2475 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
2476 (unsigned long) &rfc);
2477 break;
2478
2479 case L2CAP_MODE_ERTM:
2480 rfc.mode = L2CAP_MODE_ERTM;
2481 rfc.max_transmit = chan->max_tx;
2482 rfc.retrans_timeout = 0;
2483 rfc.monitor_timeout = 0;
2484
2485 size = min_t(u16, L2CAP_DEFAULT_MAX_PDU_SIZE, chan->conn->mtu -
2486 L2CAP_EXT_HDR_SIZE -
2487 L2CAP_SDULEN_SIZE -
2488 L2CAP_FCS_SIZE);
2489 rfc.max_pdu_size = cpu_to_le16(size);
2490
2491 l2cap_txwin_setup(chan);
2492
2493 rfc.txwin_size = min_t(u16, chan->tx_win,
2494 L2CAP_DEFAULT_TX_WINDOW);
2495
2496 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
2497 (unsigned long) &rfc);
2498
2499 if (test_bit(FLAG_EFS_ENABLE, &chan->flags))
2500 l2cap_add_opt_efs(&ptr, chan);
2501
2502 if (!(chan->conn->feat_mask & L2CAP_FEAT_FCS))
2503 break;
2504
2505 if (chan->fcs == L2CAP_FCS_NONE ||
2506 test_bit(CONF_NO_FCS_RECV, &chan->conf_state)) {
2507 chan->fcs = L2CAP_FCS_NONE;
2508 l2cap_add_conf_opt(&ptr, L2CAP_CONF_FCS, 1, chan->fcs);
2509 }
2510
2511 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
2512 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EWS, 2,
2513 chan->tx_win);
2514 break;
2515
2516 case L2CAP_MODE_STREAMING:
2517 rfc.mode = L2CAP_MODE_STREAMING;
2518 rfc.txwin_size = 0;
2519 rfc.max_transmit = 0;
2520 rfc.retrans_timeout = 0;
2521 rfc.monitor_timeout = 0;
2522
2523 size = min_t(u16, L2CAP_DEFAULT_MAX_PDU_SIZE, chan->conn->mtu -
2524 L2CAP_EXT_HDR_SIZE -
2525 L2CAP_SDULEN_SIZE -
2526 L2CAP_FCS_SIZE);
2527 rfc.max_pdu_size = cpu_to_le16(size);
2528
2529 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
2530 (unsigned long) &rfc);
2531
2532 if (test_bit(FLAG_EFS_ENABLE, &chan->flags))
2533 l2cap_add_opt_efs(&ptr, chan);
2534
2535 if (!(chan->conn->feat_mask & L2CAP_FEAT_FCS))
2536 break;
2537
2538 if (chan->fcs == L2CAP_FCS_NONE ||
2539 test_bit(CONF_NO_FCS_RECV, &chan->conf_state)) {
2540 chan->fcs = L2CAP_FCS_NONE;
2541 l2cap_add_conf_opt(&ptr, L2CAP_CONF_FCS, 1, chan->fcs);
2542 }
2543 break;
2544 }
2545
2546 req->dcid = cpu_to_le16(chan->dcid);
2547 req->flags = cpu_to_le16(0);
2548
2549 return ptr - data;
2550}
2551
2552static int l2cap_parse_conf_req(struct l2cap_chan *chan, void *data)
2553{
2554 struct l2cap_conf_rsp *rsp = data;
2555 void *ptr = rsp->data;
2556 void *req = chan->conf_req;
2557 int len = chan->conf_len;
2558 int type, hint, olen;
2559 unsigned long val;
2560 struct l2cap_conf_rfc rfc = { .mode = L2CAP_MODE_BASIC };
2561 struct l2cap_conf_efs efs;
2562 u8 remote_efs = 0;
2563 u16 mtu = L2CAP_DEFAULT_MTU;
2564 u16 result = L2CAP_CONF_SUCCESS;
2565 u16 size;
2566
2567 BT_DBG("chan %p", chan);
2568
2569 while (len >= L2CAP_CONF_OPT_SIZE) {
2570 len -= l2cap_get_conf_opt(&req, &type, &olen, &val);
2571
2572 hint = type & L2CAP_CONF_HINT;
2573 type &= L2CAP_CONF_MASK;
2574
2575 switch (type) {
2576 case L2CAP_CONF_MTU:
2577 mtu = val;
2578 break;
2579
2580 case L2CAP_CONF_FLUSH_TO:
2581 chan->flush_to = val;
2582 break;
2583
2584 case L2CAP_CONF_QOS:
2585 break;
2586
2587 case L2CAP_CONF_RFC:
2588 if (olen == sizeof(rfc))
2589 memcpy(&rfc, (void *) val, olen);
2590 break;
2591
2592 case L2CAP_CONF_FCS:
2593 if (val == L2CAP_FCS_NONE)
2594 set_bit(CONF_NO_FCS_RECV, &chan->conf_state);
2595 break;
2596
2597 case L2CAP_CONF_EFS:
2598 remote_efs = 1;
2599 if (olen == sizeof(efs))
2600 memcpy(&efs, (void *) val, olen);
2601 break;
2602
2603 case L2CAP_CONF_EWS:
2604 if (!enable_hs)
2605 return -ECONNREFUSED;
2606
2607 set_bit(FLAG_EXT_CTRL, &chan->flags);
2608 set_bit(CONF_EWS_RECV, &chan->conf_state);
2609 chan->tx_win_max = L2CAP_DEFAULT_EXT_WINDOW;
2610 chan->remote_tx_win = val;
2611 break;
2612
2613 default:
2614 if (hint)
2615 break;
2616
2617 result = L2CAP_CONF_UNKNOWN;
2618 *((u8 *) ptr++) = type;
2619 break;
2620 }
2621 }
2622
2623 if (chan->num_conf_rsp || chan->num_conf_req > 1)
2624 goto done;
2625
2626 switch (chan->mode) {
2627 case L2CAP_MODE_STREAMING:
2628 case L2CAP_MODE_ERTM:
2629 if (!test_bit(CONF_STATE2_DEVICE, &chan->conf_state)) {
2630 chan->mode = l2cap_select_mode(rfc.mode,
2631 chan->conn->feat_mask);
2632 break;
2633 }
2634
2635 if (remote_efs) {
2636 if (__l2cap_efs_supported(chan))
2637 set_bit(FLAG_EFS_ENABLE, &chan->flags);
2638 else
2639 return -ECONNREFUSED;
2640 }
2641
2642 if (chan->mode != rfc.mode)
2643 return -ECONNREFUSED;
2644
2645 break;
2646 }
2647
2648done:
2649 if (chan->mode != rfc.mode) {
2650 result = L2CAP_CONF_UNACCEPT;
2651 rfc.mode = chan->mode;
2652
2653 if (chan->num_conf_rsp == 1)
2654 return -ECONNREFUSED;
2655
2656 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC,
2657 sizeof(rfc), (unsigned long) &rfc);
2658 }
2659
2660 if (result == L2CAP_CONF_SUCCESS) {
2661 /* Configure output options and let the other side know
2662 * which ones we don't like. */
2663
2664 if (mtu < L2CAP_DEFAULT_MIN_MTU)
2665 result = L2CAP_CONF_UNACCEPT;
2666 else {
2667 chan->omtu = mtu;
2668 set_bit(CONF_MTU_DONE, &chan->conf_state);
2669 }
2670 l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->omtu);
2671
2672 if (remote_efs) {
2673 if (chan->local_stype != L2CAP_SERV_NOTRAFIC &&
2674 efs.stype != L2CAP_SERV_NOTRAFIC &&
2675 efs.stype != chan->local_stype) {
2676
2677 result = L2CAP_CONF_UNACCEPT;
2678
2679 if (chan->num_conf_req >= 1)
2680 return -ECONNREFUSED;
2681
2682 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS,
2683 sizeof(efs),
2684 (unsigned long) &efs);
2685 } else {
2686 /* Send PENDING Conf Rsp */
2687 result = L2CAP_CONF_PENDING;
2688 set_bit(CONF_LOC_CONF_PEND, &chan->conf_state);
2689 }
2690 }
2691
2692 switch (rfc.mode) {
2693 case L2CAP_MODE_BASIC:
2694 chan->fcs = L2CAP_FCS_NONE;
2695 set_bit(CONF_MODE_DONE, &chan->conf_state);
2696 break;
2697
2698 case L2CAP_MODE_ERTM:
2699 if (!test_bit(CONF_EWS_RECV, &chan->conf_state))
2700 chan->remote_tx_win = rfc.txwin_size;
2701 else
2702 rfc.txwin_size = L2CAP_DEFAULT_TX_WINDOW;
2703
2704 chan->remote_max_tx = rfc.max_transmit;
2705
2706 size = min_t(u16, le16_to_cpu(rfc.max_pdu_size),
2707 chan->conn->mtu -
2708 L2CAP_EXT_HDR_SIZE -
2709 L2CAP_SDULEN_SIZE -
2710 L2CAP_FCS_SIZE);
2711 rfc.max_pdu_size = cpu_to_le16(size);
2712 chan->remote_mps = size;
2713
2714 rfc.retrans_timeout =
2715 __constant_cpu_to_le16(L2CAP_DEFAULT_RETRANS_TO);
2716 rfc.monitor_timeout =
2717 __constant_cpu_to_le16(L2CAP_DEFAULT_MONITOR_TO);
2718
2719 set_bit(CONF_MODE_DONE, &chan->conf_state);
2720
2721 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC,
2722 sizeof(rfc), (unsigned long) &rfc);
2723
2724 if (test_bit(FLAG_EFS_ENABLE, &chan->flags)) {
2725 chan->remote_id = efs.id;
2726 chan->remote_stype = efs.stype;
2727 chan->remote_msdu = le16_to_cpu(efs.msdu);
2728 chan->remote_flush_to =
2729 le32_to_cpu(efs.flush_to);
2730 chan->remote_acc_lat =
2731 le32_to_cpu(efs.acc_lat);
2732 chan->remote_sdu_itime =
2733 le32_to_cpu(efs.sdu_itime);
2734 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS,
2735 sizeof(efs), (unsigned long) &efs);
2736 }
2737 break;
2738
2739 case L2CAP_MODE_STREAMING:
2740 size = min_t(u16, le16_to_cpu(rfc.max_pdu_size),
2741 chan->conn->mtu -
2742 L2CAP_EXT_HDR_SIZE -
2743 L2CAP_SDULEN_SIZE -
2744 L2CAP_FCS_SIZE);
2745 rfc.max_pdu_size = cpu_to_le16(size);
2746 chan->remote_mps = size;
2747
2748 set_bit(CONF_MODE_DONE, &chan->conf_state);
2749
2750 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC,
2751 sizeof(rfc), (unsigned long) &rfc);
2752
2753 break;
2754
2755 default:
2756 result = L2CAP_CONF_UNACCEPT;
2757
2758 memset(&rfc, 0, sizeof(rfc));
2759 rfc.mode = chan->mode;
2760 }
2761
2762 if (result == L2CAP_CONF_SUCCESS)
2763 set_bit(CONF_OUTPUT_DONE, &chan->conf_state);
2764 }
2765 rsp->scid = cpu_to_le16(chan->dcid);
2766 rsp->result = cpu_to_le16(result);
2767 rsp->flags = cpu_to_le16(0x0000);
2768
2769 return ptr - data;
2770}
2771
2772static int l2cap_parse_conf_rsp(struct l2cap_chan *chan, void *rsp, int len, void *data, u16 *result)
2773{
2774 struct l2cap_conf_req *req = data;
2775 void *ptr = req->data;
2776 int type, olen;
2777 unsigned long val;
2778 struct l2cap_conf_rfc rfc = { .mode = L2CAP_MODE_BASIC };
2779 struct l2cap_conf_efs efs;
2780
2781 BT_DBG("chan %p, rsp %p, len %d, req %p", chan, rsp, len, data);
2782
2783 while (len >= L2CAP_CONF_OPT_SIZE) {
2784 len -= l2cap_get_conf_opt(&rsp, &type, &olen, &val);
2785
2786 switch (type) {
2787 case L2CAP_CONF_MTU:
2788 if (val < L2CAP_DEFAULT_MIN_MTU) {
2789 *result = L2CAP_CONF_UNACCEPT;
2790 chan->imtu = L2CAP_DEFAULT_MIN_MTU;
2791 } else
2792 chan->imtu = val;
2793 l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->imtu);
2794 break;
2795
2796 case L2CAP_CONF_FLUSH_TO:
2797 chan->flush_to = val;
2798 l2cap_add_conf_opt(&ptr, L2CAP_CONF_FLUSH_TO,
2799 2, chan->flush_to);
2800 break;
2801
2802 case L2CAP_CONF_RFC:
2803 if (olen == sizeof(rfc))
2804 memcpy(&rfc, (void *)val, olen);
2805
2806 if (test_bit(CONF_STATE2_DEVICE, &chan->conf_state) &&
2807 rfc.mode != chan->mode)
2808 return -ECONNREFUSED;
2809
2810 chan->fcs = 0;
2811
2812 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC,
2813 sizeof(rfc), (unsigned long) &rfc);
2814 break;
2815
2816 case L2CAP_CONF_EWS:
2817 chan->tx_win = min_t(u16, val,
2818 L2CAP_DEFAULT_EXT_WINDOW);
2819 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EWS, 2,
2820 chan->tx_win);
2821 break;
2822
2823 case L2CAP_CONF_EFS:
2824 if (olen == sizeof(efs))
2825 memcpy(&efs, (void *)val, olen);
2826
2827 if (chan->local_stype != L2CAP_SERV_NOTRAFIC &&
2828 efs.stype != L2CAP_SERV_NOTRAFIC &&
2829 efs.stype != chan->local_stype)
2830 return -ECONNREFUSED;
2831
2832 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS,
2833 sizeof(efs), (unsigned long) &efs);
2834 break;
2835 }
2836 }
2837
2838 if (chan->mode == L2CAP_MODE_BASIC && chan->mode != rfc.mode)
2839 return -ECONNREFUSED;
2840
2841 chan->mode = rfc.mode;
2842
2843 if (*result == L2CAP_CONF_SUCCESS || *result == L2CAP_CONF_PENDING) {
2844 switch (rfc.mode) {
2845 case L2CAP_MODE_ERTM:
2846 chan->retrans_timeout = le16_to_cpu(rfc.retrans_timeout);
2847 chan->monitor_timeout = le16_to_cpu(rfc.monitor_timeout);
2848 chan->mps = le16_to_cpu(rfc.max_pdu_size);
2849
2850 if (test_bit(FLAG_EFS_ENABLE, &chan->flags)) {
2851 chan->local_msdu = le16_to_cpu(efs.msdu);
2852 chan->local_sdu_itime =
2853 le32_to_cpu(efs.sdu_itime);
2854 chan->local_acc_lat = le32_to_cpu(efs.acc_lat);
2855 chan->local_flush_to =
2856 le32_to_cpu(efs.flush_to);
2857 }
2858 break;
2859
2860 case L2CAP_MODE_STREAMING:
2861 chan->mps = le16_to_cpu(rfc.max_pdu_size);
2862 }
2863 }
2864
2865 req->dcid = cpu_to_le16(chan->dcid);
2866 req->flags = cpu_to_le16(0x0000);
2867
2868 return ptr - data;
2869}
2870
2871static int l2cap_build_conf_rsp(struct l2cap_chan *chan, void *data, u16 result, u16 flags)
2872{
2873 struct l2cap_conf_rsp *rsp = data;
2874 void *ptr = rsp->data;
2875
2876 BT_DBG("chan %p", chan);
2877
2878 rsp->scid = cpu_to_le16(chan->dcid);
2879 rsp->result = cpu_to_le16(result);
2880 rsp->flags = cpu_to_le16(flags);
2881
2882 return ptr - data;
2883}
2884
2885void __l2cap_connect_rsp_defer(struct l2cap_chan *chan)
2886{
2887 struct l2cap_conn_rsp rsp;
2888 struct l2cap_conn *conn = chan->conn;
2889 u8 buf[128];
2890
2891 rsp.scid = cpu_to_le16(chan->dcid);
2892 rsp.dcid = cpu_to_le16(chan->scid);
2893 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
2894 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
2895 l2cap_send_cmd(conn, chan->ident,
2896 L2CAP_CONN_RSP, sizeof(rsp), &rsp);
2897
2898 if (test_and_set_bit(CONF_REQ_SENT, &chan->conf_state))
2899 return;
2900
2901 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
2902 l2cap_build_conf_req(chan, buf), buf);
2903 chan->num_conf_req++;
2904}
2905
2906static void l2cap_conf_rfc_get(struct l2cap_chan *chan, void *rsp, int len)
2907{
2908 int type, olen;
2909 unsigned long val;
2910 struct l2cap_conf_rfc rfc;
2911
2912 BT_DBG("chan %p, rsp %p, len %d", chan, rsp, len);
2913
2914 if ((chan->mode != L2CAP_MODE_ERTM) && (chan->mode != L2CAP_MODE_STREAMING))
2915 return;
2916
2917 while (len >= L2CAP_CONF_OPT_SIZE) {
2918 len -= l2cap_get_conf_opt(&rsp, &type, &olen, &val);
2919
2920 if (type != L2CAP_CONF_RFC)
2921 continue;
2922
2923 if (olen != sizeof(rfc))
2924 break;
2925
2926 memcpy(&rfc, (void *)val, olen);
2927 goto done;
2928 }
2929
2930 /* Use sane default values in case a misbehaving remote device
2931 * did not send an RFC option.
2932 */
2933 rfc.mode = chan->mode;
2934 rfc.retrans_timeout = cpu_to_le16(L2CAP_DEFAULT_RETRANS_TO);
2935 rfc.monitor_timeout = cpu_to_le16(L2CAP_DEFAULT_MONITOR_TO);
2936 rfc.max_pdu_size = cpu_to_le16(chan->imtu);
2937
2938 BT_ERR("Expected RFC option was not found, using defaults");
2939
2940done:
2941 switch (rfc.mode) {
2942 case L2CAP_MODE_ERTM:
2943 chan->retrans_timeout = le16_to_cpu(rfc.retrans_timeout);
2944 chan->monitor_timeout = le16_to_cpu(rfc.monitor_timeout);
2945 chan->mps = le16_to_cpu(rfc.max_pdu_size);
2946 break;
2947 case L2CAP_MODE_STREAMING:
2948 chan->mps = le16_to_cpu(rfc.max_pdu_size);
2949 }
2950}
2951
2952static inline int l2cap_command_rej(struct l2cap_conn *conn, struct l2cap_cmd_hdr *cmd, u8 *data)
2953{
2954 struct l2cap_cmd_rej_unk *rej = (struct l2cap_cmd_rej_unk *) data;
2955
2956 if (rej->reason != L2CAP_REJ_NOT_UNDERSTOOD)
2957 return 0;
2958
2959 if ((conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT) &&
2960 cmd->ident == conn->info_ident) {
2961 cancel_delayed_work(&conn->info_timer);
2962
2963 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
2964 conn->info_ident = 0;
2965
2966 l2cap_conn_start(conn);
2967 }
2968
2969 return 0;
2970}
2971
2972static inline int l2cap_connect_req(struct l2cap_conn *conn, struct l2cap_cmd_hdr *cmd, u8 *data)
2973{
2974 struct l2cap_conn_req *req = (struct l2cap_conn_req *) data;
2975 struct l2cap_conn_rsp rsp;
2976 struct l2cap_chan *chan = NULL, *pchan;
2977 struct sock *parent, *sk = NULL;
2978 int result, status = L2CAP_CS_NO_INFO;
2979
2980 u16 dcid = 0, scid = __le16_to_cpu(req->scid);
2981 __le16 psm = req->psm;
2982
2983 BT_DBG("psm 0x%2.2x scid 0x%4.4x", __le16_to_cpu(psm), scid);
2984
2985 /* Check if we have socket listening on psm */
2986 pchan = l2cap_global_chan_by_psm(BT_LISTEN, psm, conn->src, conn->dst);
2987 if (!pchan) {
2988 result = L2CAP_CR_BAD_PSM;
2989 goto sendresp;
2990 }
2991
2992 parent = pchan->sk;
2993
2994 mutex_lock(&conn->chan_lock);
2995 lock_sock(parent);
2996
2997 /* Check if the ACL is secure enough (if not SDP) */
2998 if (psm != cpu_to_le16(0x0001) &&
2999 !hci_conn_check_link_mode(conn->hcon)) {
3000 conn->disc_reason = HCI_ERROR_AUTH_FAILURE;
3001 result = L2CAP_CR_SEC_BLOCK;
3002 goto response;
3003 }
3004
3005 result = L2CAP_CR_NO_MEM;
3006
3007 /* Check for backlog size */
3008 if (sk_acceptq_is_full(parent)) {
3009 BT_DBG("backlog full %d", parent->sk_ack_backlog);
3010 goto response;
3011 }
3012
3013 chan = pchan->ops->new_connection(pchan->data);
3014 if (!chan)
3015 goto response;
3016
3017 sk = chan->sk;
3018
3019 /* Check if we already have channel with that dcid */
3020 if (__l2cap_get_chan_by_dcid(conn, scid)) {
3021 sock_set_flag(sk, SOCK_ZAPPED);
3022 chan->ops->close(chan->data);
3023 goto response;
3024 }
3025
3026 hci_conn_hold(conn->hcon);
3027
3028 bacpy(&bt_sk(sk)->src, conn->src);
3029 bacpy(&bt_sk(sk)->dst, conn->dst);
3030 chan->psm = psm;
3031 chan->dcid = scid;
3032
3033 bt_accept_enqueue(parent, sk);
3034
3035 __l2cap_chan_add(conn, chan);
3036
3037 dcid = chan->scid;
3038
3039 __set_chan_timer(chan, sk->sk_sndtimeo);
3040
3041 chan->ident = cmd->ident;
3042
3043 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE) {
3044 if (l2cap_chan_check_security(chan)) {
3045 if (test_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags)) {
3046 __l2cap_state_change(chan, BT_CONNECT2);
3047 result = L2CAP_CR_PEND;
3048 status = L2CAP_CS_AUTHOR_PEND;
3049 parent->sk_data_ready(parent, 0);
3050 } else {
3051 __l2cap_state_change(chan, BT_CONFIG);
3052 result = L2CAP_CR_SUCCESS;
3053 status = L2CAP_CS_NO_INFO;
3054 }
3055 } else {
3056 __l2cap_state_change(chan, BT_CONNECT2);
3057 result = L2CAP_CR_PEND;
3058 status = L2CAP_CS_AUTHEN_PEND;
3059 }
3060 } else {
3061 __l2cap_state_change(chan, BT_CONNECT2);
3062 result = L2CAP_CR_PEND;
3063 status = L2CAP_CS_NO_INFO;
3064 }
3065
3066response:
3067 release_sock(parent);
3068 mutex_unlock(&conn->chan_lock);
3069
3070sendresp:
3071 rsp.scid = cpu_to_le16(scid);
3072 rsp.dcid = cpu_to_le16(dcid);
3073 rsp.result = cpu_to_le16(result);
3074 rsp.status = cpu_to_le16(status);
3075 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONN_RSP, sizeof(rsp), &rsp);
3076
3077 if (result == L2CAP_CR_PEND && status == L2CAP_CS_NO_INFO) {
3078 struct l2cap_info_req info;
3079 info.type = cpu_to_le16(L2CAP_IT_FEAT_MASK);
3080
3081 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_SENT;
3082 conn->info_ident = l2cap_get_ident(conn);
3083
3084 schedule_delayed_work(&conn->info_timer, L2CAP_INFO_TIMEOUT);
3085
3086 l2cap_send_cmd(conn, conn->info_ident,
3087 L2CAP_INFO_REQ, sizeof(info), &info);
3088 }
3089
3090 if (chan && !test_bit(CONF_REQ_SENT, &chan->conf_state) &&
3091 result == L2CAP_CR_SUCCESS) {
3092 u8 buf[128];
3093 set_bit(CONF_REQ_SENT, &chan->conf_state);
3094 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
3095 l2cap_build_conf_req(chan, buf), buf);
3096 chan->num_conf_req++;
3097 }
3098
3099 return 0;
3100}
3101
3102static inline int l2cap_connect_rsp(struct l2cap_conn *conn, struct l2cap_cmd_hdr *cmd, u8 *data)
3103{
3104 struct l2cap_conn_rsp *rsp = (struct l2cap_conn_rsp *) data;
3105 u16 scid, dcid, result, status;
3106 struct l2cap_chan *chan;
3107 u8 req[128];
3108 int err;
3109
3110 scid = __le16_to_cpu(rsp->scid);
3111 dcid = __le16_to_cpu(rsp->dcid);
3112 result = __le16_to_cpu(rsp->result);
3113 status = __le16_to_cpu(rsp->status);
3114
3115 BT_DBG("dcid 0x%4.4x scid 0x%4.4x result 0x%2.2x status 0x%2.2x",
3116 dcid, scid, result, status);
3117
3118 mutex_lock(&conn->chan_lock);
3119
3120 if (scid) {
3121 chan = __l2cap_get_chan_by_scid(conn, scid);
3122 if (!chan) {
3123 err = -EFAULT;
3124 goto unlock;
3125 }
3126 } else {
3127 chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
3128 if (!chan) {
3129 err = -EFAULT;
3130 goto unlock;
3131 }
3132 }
3133
3134 err = 0;
3135
3136 l2cap_chan_lock(chan);
3137
3138 switch (result) {
3139 case L2CAP_CR_SUCCESS:
3140 l2cap_state_change(chan, BT_CONFIG);
3141 chan->ident = 0;
3142 chan->dcid = dcid;
3143 clear_bit(CONF_CONNECT_PEND, &chan->conf_state);
3144
3145 if (test_and_set_bit(CONF_REQ_SENT, &chan->conf_state))
3146 break;
3147
3148 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
3149 l2cap_build_conf_req(chan, req), req);
3150 chan->num_conf_req++;
3151 break;
3152
3153 case L2CAP_CR_PEND:
3154 set_bit(CONF_CONNECT_PEND, &chan->conf_state);
3155 break;
3156
3157 default:
3158 l2cap_chan_del(chan, ECONNREFUSED);
3159 break;
3160 }
3161
3162 l2cap_chan_unlock(chan);
3163
3164unlock:
3165 mutex_unlock(&conn->chan_lock);
3166
3167 return err;
3168}
3169
3170static inline void set_default_fcs(struct l2cap_chan *chan)
3171{
3172 /* FCS is enabled only in ERTM or streaming mode, if one or both
3173 * sides request it.
3174 */
3175 if (chan->mode != L2CAP_MODE_ERTM && chan->mode != L2CAP_MODE_STREAMING)
3176 chan->fcs = L2CAP_FCS_NONE;
3177 else if (!test_bit(CONF_NO_FCS_RECV, &chan->conf_state))
3178 chan->fcs = L2CAP_FCS_CRC16;
3179}
3180
3181static inline int l2cap_config_req(struct l2cap_conn *conn, struct l2cap_cmd_hdr *cmd, u16 cmd_len, u8 *data)
3182{
3183 struct l2cap_conf_req *req = (struct l2cap_conf_req *) data;
3184 u16 dcid, flags;
3185 u8 rsp[64];
3186 struct l2cap_chan *chan;
3187 int len, err = 0;
3188
3189 dcid = __le16_to_cpu(req->dcid);
3190 flags = __le16_to_cpu(req->flags);
3191
3192 BT_DBG("dcid 0x%4.4x flags 0x%2.2x", dcid, flags);
3193
3194 chan = l2cap_get_chan_by_scid(conn, dcid);
3195 if (!chan)
3196 return -ENOENT;
3197
3198 if (chan->state != BT_CONFIG && chan->state != BT_CONNECT2) {
3199 struct l2cap_cmd_rej_cid rej;
3200
3201 rej.reason = cpu_to_le16(L2CAP_REJ_INVALID_CID);
3202 rej.scid = cpu_to_le16(chan->scid);
3203 rej.dcid = cpu_to_le16(chan->dcid);
3204
3205 l2cap_send_cmd(conn, cmd->ident, L2CAP_COMMAND_REJ,
3206 sizeof(rej), &rej);
3207 goto unlock;
3208 }
3209
3210 /* Reject if config buffer is too small. */
3211 len = cmd_len - sizeof(*req);
3212 if (len < 0 || chan->conf_len + len > sizeof(chan->conf_req)) {
3213 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP,
3214 l2cap_build_conf_rsp(chan, rsp,
3215 L2CAP_CONF_REJECT, flags), rsp);
3216 goto unlock;
3217 }
3218
3219 /* Store config. */
3220 memcpy(chan->conf_req + chan->conf_len, req->data, len);
3221 chan->conf_len += len;
3222
3223 if (flags & 0x0001) {
3224 /* Incomplete config. Send empty response. */
3225 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP,
3226 l2cap_build_conf_rsp(chan, rsp,
3227 L2CAP_CONF_SUCCESS, 0x0001), rsp);
3228 goto unlock;
3229 }
3230
3231 /* Complete config. */
3232 len = l2cap_parse_conf_req(chan, rsp);
3233 if (len < 0) {
3234 l2cap_send_disconn_req(conn, chan, ECONNRESET);
3235 goto unlock;
3236 }
3237
3238 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP, len, rsp);
3239 chan->num_conf_rsp++;
3240
3241 /* Reset config buffer. */
3242 chan->conf_len = 0;
3243
3244 if (!test_bit(CONF_OUTPUT_DONE, &chan->conf_state))
3245 goto unlock;
3246
3247 if (test_bit(CONF_INPUT_DONE, &chan->conf_state)) {
3248 set_default_fcs(chan);
3249
3250 l2cap_state_change(chan, BT_CONNECTED);
3251
3252 if (chan->mode == L2CAP_MODE_ERTM ||
3253 chan->mode == L2CAP_MODE_STREAMING)
3254 err = l2cap_ertm_init(chan);
3255
3256 if (err < 0)
3257 l2cap_send_disconn_req(chan->conn, chan, -err);
3258 else
3259 l2cap_chan_ready(chan);
3260
3261 goto unlock;
3262 }
3263
3264 if (!test_and_set_bit(CONF_REQ_SENT, &chan->conf_state)) {
3265 u8 buf[64];
3266 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
3267 l2cap_build_conf_req(chan, buf), buf);
3268 chan->num_conf_req++;
3269 }
3270
3271 /* Got Conf Rsp PENDING from remote side and asume we sent
3272 Conf Rsp PENDING in the code above */
3273 if (test_bit(CONF_REM_CONF_PEND, &chan->conf_state) &&
3274 test_bit(CONF_LOC_CONF_PEND, &chan->conf_state)) {
3275
3276 /* check compatibility */
3277
3278 clear_bit(CONF_LOC_CONF_PEND, &chan->conf_state);
3279 set_bit(CONF_OUTPUT_DONE, &chan->conf_state);
3280
3281 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP,
3282 l2cap_build_conf_rsp(chan, rsp,
3283 L2CAP_CONF_SUCCESS, 0x0000), rsp);
3284 }
3285
3286unlock:
3287 l2cap_chan_unlock(chan);
3288 return err;
3289}
3290
3291static inline int l2cap_config_rsp(struct l2cap_conn *conn, struct l2cap_cmd_hdr *cmd, u8 *data)
3292{
3293 struct l2cap_conf_rsp *rsp = (struct l2cap_conf_rsp *)data;
3294 u16 scid, flags, result;
3295 struct l2cap_chan *chan;
3296 int len = le16_to_cpu(cmd->len) - sizeof(*rsp);
3297 int err = 0;
3298
3299 scid = __le16_to_cpu(rsp->scid);
3300 flags = __le16_to_cpu(rsp->flags);
3301 result = __le16_to_cpu(rsp->result);
3302
3303 BT_DBG("scid 0x%4.4x flags 0x%2.2x result 0x%2.2x len %d", scid, flags,
3304 result, len);
3305
3306 chan = l2cap_get_chan_by_scid(conn, scid);
3307 if (!chan)
3308 return 0;
3309
3310 switch (result) {
3311 case L2CAP_CONF_SUCCESS:
3312 l2cap_conf_rfc_get(chan, rsp->data, len);
3313 clear_bit(CONF_REM_CONF_PEND, &chan->conf_state);
3314 break;
3315
3316 case L2CAP_CONF_PENDING:
3317 set_bit(CONF_REM_CONF_PEND, &chan->conf_state);
3318
3319 if (test_bit(CONF_LOC_CONF_PEND, &chan->conf_state)) {
3320 char buf[64];
3321
3322 len = l2cap_parse_conf_rsp(chan, rsp->data, len,
3323 buf, &result);
3324 if (len < 0) {
3325 l2cap_send_disconn_req(conn, chan, ECONNRESET);
3326 goto done;
3327 }
3328
3329 /* check compatibility */
3330
3331 clear_bit(CONF_LOC_CONF_PEND, &chan->conf_state);
3332 set_bit(CONF_OUTPUT_DONE, &chan->conf_state);
3333
3334 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP,
3335 l2cap_build_conf_rsp(chan, buf,
3336 L2CAP_CONF_SUCCESS, 0x0000), buf);
3337 }
3338 goto done;
3339
3340 case L2CAP_CONF_UNACCEPT:
3341 if (chan->num_conf_rsp <= L2CAP_CONF_MAX_CONF_RSP) {
3342 char req[64];
3343
3344 if (len > sizeof(req) - sizeof(struct l2cap_conf_req)) {
3345 l2cap_send_disconn_req(conn, chan, ECONNRESET);
3346 goto done;
3347 }
3348
3349 /* throw out any old stored conf requests */
3350 result = L2CAP_CONF_SUCCESS;
3351 len = l2cap_parse_conf_rsp(chan, rsp->data, len,
3352 req, &result);
3353 if (len < 0) {
3354 l2cap_send_disconn_req(conn, chan, ECONNRESET);
3355 goto done;
3356 }
3357
3358 l2cap_send_cmd(conn, l2cap_get_ident(conn),
3359 L2CAP_CONF_REQ, len, req);
3360 chan->num_conf_req++;
3361 if (result != L2CAP_CONF_SUCCESS)
3362 goto done;
3363 break;
3364 }
3365
3366 default:
3367 l2cap_chan_set_err(chan, ECONNRESET);
3368
3369 __set_chan_timer(chan, L2CAP_DISC_REJ_TIMEOUT);
3370 l2cap_send_disconn_req(conn, chan, ECONNRESET);
3371 goto done;
3372 }
3373
3374 if (flags & 0x01)
3375 goto done;
3376
3377 set_bit(CONF_INPUT_DONE, &chan->conf_state);
3378
3379 if (test_bit(CONF_OUTPUT_DONE, &chan->conf_state)) {
3380 set_default_fcs(chan);
3381
3382 l2cap_state_change(chan, BT_CONNECTED);
3383 if (chan->mode == L2CAP_MODE_ERTM ||
3384 chan->mode == L2CAP_MODE_STREAMING)
3385 err = l2cap_ertm_init(chan);
3386
3387 if (err < 0)
3388 l2cap_send_disconn_req(chan->conn, chan, -err);
3389 else
3390 l2cap_chan_ready(chan);
3391 }
3392
3393done:
3394 l2cap_chan_unlock(chan);
3395 return err;
3396}
3397
3398static inline int l2cap_disconnect_req(struct l2cap_conn *conn, struct l2cap_cmd_hdr *cmd, u8 *data)
3399{
3400 struct l2cap_disconn_req *req = (struct l2cap_disconn_req *) data;
3401 struct l2cap_disconn_rsp rsp;
3402 u16 dcid, scid;
3403 struct l2cap_chan *chan;
3404 struct sock *sk;
3405
3406 scid = __le16_to_cpu(req->scid);
3407 dcid = __le16_to_cpu(req->dcid);
3408
3409 BT_DBG("scid 0x%4.4x dcid 0x%4.4x", scid, dcid);
3410
3411 mutex_lock(&conn->chan_lock);
3412
3413 chan = __l2cap_get_chan_by_scid(conn, dcid);
3414 if (!chan) {
3415 mutex_unlock(&conn->chan_lock);
3416 return 0;
3417 }
3418
3419 l2cap_chan_lock(chan);
3420
3421 sk = chan->sk;
3422
3423 rsp.dcid = cpu_to_le16(chan->scid);
3424 rsp.scid = cpu_to_le16(chan->dcid);
3425 l2cap_send_cmd(conn, cmd->ident, L2CAP_DISCONN_RSP, sizeof(rsp), &rsp);
3426
3427 lock_sock(sk);
3428 sk->sk_shutdown = SHUTDOWN_MASK;
3429 release_sock(sk);
3430
3431 l2cap_chan_hold(chan);
3432 l2cap_chan_del(chan, ECONNRESET);
3433
3434 l2cap_chan_unlock(chan);
3435
3436 chan->ops->close(chan->data);
3437 l2cap_chan_put(chan);
3438
3439 mutex_unlock(&conn->chan_lock);
3440
3441 return 0;
3442}
3443
3444static inline int l2cap_disconnect_rsp(struct l2cap_conn *conn, struct l2cap_cmd_hdr *cmd, u8 *data)
3445{
3446 struct l2cap_disconn_rsp *rsp = (struct l2cap_disconn_rsp *) data;
3447 u16 dcid, scid;
3448 struct l2cap_chan *chan;
3449
3450 scid = __le16_to_cpu(rsp->scid);
3451 dcid = __le16_to_cpu(rsp->dcid);
3452
3453 BT_DBG("dcid 0x%4.4x scid 0x%4.4x", dcid, scid);
3454
3455 mutex_lock(&conn->chan_lock);
3456
3457 chan = __l2cap_get_chan_by_scid(conn, scid);
3458 if (!chan) {
3459 mutex_unlock(&conn->chan_lock);
3460 return 0;
3461 }
3462
3463 l2cap_chan_lock(chan);
3464
3465 l2cap_chan_hold(chan);
3466 l2cap_chan_del(chan, 0);
3467
3468 l2cap_chan_unlock(chan);
3469
3470 chan->ops->close(chan->data);
3471 l2cap_chan_put(chan);
3472
3473 mutex_unlock(&conn->chan_lock);
3474
3475 return 0;
3476}
3477
3478static inline int l2cap_information_req(struct l2cap_conn *conn, struct l2cap_cmd_hdr *cmd, u8 *data)
3479{
3480 struct l2cap_info_req *req = (struct l2cap_info_req *) data;
3481 u16 type;
3482
3483 type = __le16_to_cpu(req->type);
3484
3485 BT_DBG("type 0x%4.4x", type);
3486
3487 if (type == L2CAP_IT_FEAT_MASK) {
3488 u8 buf[8];
3489 u32 feat_mask = l2cap_feat_mask;
3490 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) buf;
3491 rsp->type = cpu_to_le16(L2CAP_IT_FEAT_MASK);
3492 rsp->result = cpu_to_le16(L2CAP_IR_SUCCESS);
3493 if (!disable_ertm)
3494 feat_mask |= L2CAP_FEAT_ERTM | L2CAP_FEAT_STREAMING
3495 | L2CAP_FEAT_FCS;
3496 if (enable_hs)
3497 feat_mask |= L2CAP_FEAT_EXT_FLOW
3498 | L2CAP_FEAT_EXT_WINDOW;
3499
3500 put_unaligned_le32(feat_mask, rsp->data);
3501 l2cap_send_cmd(conn, cmd->ident,
3502 L2CAP_INFO_RSP, sizeof(buf), buf);
3503 } else if (type == L2CAP_IT_FIXED_CHAN) {
3504 u8 buf[12];
3505 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) buf;
3506
3507 if (enable_hs)
3508 l2cap_fixed_chan[0] |= L2CAP_FC_A2MP;
3509 else
3510 l2cap_fixed_chan[0] &= ~L2CAP_FC_A2MP;
3511
3512 rsp->type = cpu_to_le16(L2CAP_IT_FIXED_CHAN);
3513 rsp->result = cpu_to_le16(L2CAP_IR_SUCCESS);
3514 memcpy(rsp->data, l2cap_fixed_chan, sizeof(l2cap_fixed_chan));
3515 l2cap_send_cmd(conn, cmd->ident,
3516 L2CAP_INFO_RSP, sizeof(buf), buf);
3517 } else {
3518 struct l2cap_info_rsp rsp;
3519 rsp.type = cpu_to_le16(type);
3520 rsp.result = cpu_to_le16(L2CAP_IR_NOTSUPP);
3521 l2cap_send_cmd(conn, cmd->ident,
3522 L2CAP_INFO_RSP, sizeof(rsp), &rsp);
3523 }
3524
3525 return 0;
3526}
3527
3528static inline int l2cap_information_rsp(struct l2cap_conn *conn, struct l2cap_cmd_hdr *cmd, u8 *data)
3529{
3530 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) data;
3531 u16 type, result;
3532
3533 type = __le16_to_cpu(rsp->type);
3534 result = __le16_to_cpu(rsp->result);
3535
3536 BT_DBG("type 0x%4.4x result 0x%2.2x", type, result);
3537
3538 /* L2CAP Info req/rsp are unbound to channels, add extra checks */
3539 if (cmd->ident != conn->info_ident ||
3540 conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE)
3541 return 0;
3542
3543 cancel_delayed_work(&conn->info_timer);
3544
3545 if (result != L2CAP_IR_SUCCESS) {
3546 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
3547 conn->info_ident = 0;
3548
3549 l2cap_conn_start(conn);
3550
3551 return 0;
3552 }
3553
3554 switch (type) {
3555 case L2CAP_IT_FEAT_MASK:
3556 conn->feat_mask = get_unaligned_le32(rsp->data);
3557
3558 if (conn->feat_mask & L2CAP_FEAT_FIXED_CHAN) {
3559 struct l2cap_info_req req;
3560 req.type = cpu_to_le16(L2CAP_IT_FIXED_CHAN);
3561
3562 conn->info_ident = l2cap_get_ident(conn);
3563
3564 l2cap_send_cmd(conn, conn->info_ident,
3565 L2CAP_INFO_REQ, sizeof(req), &req);
3566 } else {
3567 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
3568 conn->info_ident = 0;
3569
3570 l2cap_conn_start(conn);
3571 }
3572 break;
3573
3574 case L2CAP_IT_FIXED_CHAN:
3575 conn->fixed_chan_mask = rsp->data[0];
3576 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
3577 conn->info_ident = 0;
3578
3579 l2cap_conn_start(conn);
3580 break;
3581 }
3582
3583 return 0;
3584}
3585
3586static inline int l2cap_create_channel_req(struct l2cap_conn *conn,
3587 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
3588 void *data)
3589{
3590 struct l2cap_create_chan_req *req = data;
3591 struct l2cap_create_chan_rsp rsp;
3592 u16 psm, scid;
3593
3594 if (cmd_len != sizeof(*req))
3595 return -EPROTO;
3596
3597 if (!enable_hs)
3598 return -EINVAL;
3599
3600 psm = le16_to_cpu(req->psm);
3601 scid = le16_to_cpu(req->scid);
3602
3603 BT_DBG("psm %d, scid %d, amp_id %d", psm, scid, req->amp_id);
3604
3605 /* Placeholder: Always reject */
3606 rsp.dcid = 0;
3607 rsp.scid = cpu_to_le16(scid);
3608 rsp.result = __constant_cpu_to_le16(L2CAP_CR_NO_MEM);
3609 rsp.status = __constant_cpu_to_le16(L2CAP_CS_NO_INFO);
3610
3611 l2cap_send_cmd(conn, cmd->ident, L2CAP_CREATE_CHAN_RSP,
3612 sizeof(rsp), &rsp);
3613
3614 return 0;
3615}
3616
3617static inline int l2cap_create_channel_rsp(struct l2cap_conn *conn,
3618 struct l2cap_cmd_hdr *cmd, void *data)
3619{
3620 BT_DBG("conn %p", conn);
3621
3622 return l2cap_connect_rsp(conn, cmd, data);
3623}
3624
3625static void l2cap_send_move_chan_rsp(struct l2cap_conn *conn, u8 ident,
3626 u16 icid, u16 result)
3627{
3628 struct l2cap_move_chan_rsp rsp;
3629
3630 BT_DBG("icid %d, result %d", icid, result);
3631
3632 rsp.icid = cpu_to_le16(icid);
3633 rsp.result = cpu_to_le16(result);
3634
3635 l2cap_send_cmd(conn, ident, L2CAP_MOVE_CHAN_RSP, sizeof(rsp), &rsp);
3636}
3637
3638static void l2cap_send_move_chan_cfm(struct l2cap_conn *conn,
3639 struct l2cap_chan *chan, u16 icid, u16 result)
3640{
3641 struct l2cap_move_chan_cfm cfm;
3642 u8 ident;
3643
3644 BT_DBG("icid %d, result %d", icid, result);
3645
3646 ident = l2cap_get_ident(conn);
3647 if (chan)
3648 chan->ident = ident;
3649
3650 cfm.icid = cpu_to_le16(icid);
3651 cfm.result = cpu_to_le16(result);
3652
3653 l2cap_send_cmd(conn, ident, L2CAP_MOVE_CHAN_CFM, sizeof(cfm), &cfm);
3654}
3655
3656static void l2cap_send_move_chan_cfm_rsp(struct l2cap_conn *conn, u8 ident,
3657 u16 icid)
3658{
3659 struct l2cap_move_chan_cfm_rsp rsp;
3660
3661 BT_DBG("icid %d", icid);
3662
3663 rsp.icid = cpu_to_le16(icid);
3664 l2cap_send_cmd(conn, ident, L2CAP_MOVE_CHAN_CFM_RSP, sizeof(rsp), &rsp);
3665}
3666
3667static inline int l2cap_move_channel_req(struct l2cap_conn *conn,
3668 struct l2cap_cmd_hdr *cmd, u16 cmd_len, void *data)
3669{
3670 struct l2cap_move_chan_req *req = data;
3671 u16 icid = 0;
3672 u16 result = L2CAP_MR_NOT_ALLOWED;
3673
3674 if (cmd_len != sizeof(*req))
3675 return -EPROTO;
3676
3677 icid = le16_to_cpu(req->icid);
3678
3679 BT_DBG("icid %d, dest_amp_id %d", icid, req->dest_amp_id);
3680
3681 if (!enable_hs)
3682 return -EINVAL;
3683
3684 /* Placeholder: Always refuse */
3685 l2cap_send_move_chan_rsp(conn, cmd->ident, icid, result);
3686
3687 return 0;
3688}
3689
3690static inline int l2cap_move_channel_rsp(struct l2cap_conn *conn,
3691 struct l2cap_cmd_hdr *cmd, u16 cmd_len, void *data)
3692{
3693 struct l2cap_move_chan_rsp *rsp = data;
3694 u16 icid, result;
3695
3696 if (cmd_len != sizeof(*rsp))
3697 return -EPROTO;
3698
3699 icid = le16_to_cpu(rsp->icid);
3700 result = le16_to_cpu(rsp->result);
3701
3702 BT_DBG("icid %d, result %d", icid, result);
3703
3704 /* Placeholder: Always unconfirmed */
3705 l2cap_send_move_chan_cfm(conn, NULL, icid, L2CAP_MC_UNCONFIRMED);
3706
3707 return 0;
3708}
3709
3710static inline int l2cap_move_channel_confirm(struct l2cap_conn *conn,
3711 struct l2cap_cmd_hdr *cmd, u16 cmd_len, void *data)
3712{
3713 struct l2cap_move_chan_cfm *cfm = data;
3714 u16 icid, result;
3715
3716 if (cmd_len != sizeof(*cfm))
3717 return -EPROTO;
3718
3719 icid = le16_to_cpu(cfm->icid);
3720 result = le16_to_cpu(cfm->result);
3721
3722 BT_DBG("icid %d, result %d", icid, result);
3723
3724 l2cap_send_move_chan_cfm_rsp(conn, cmd->ident, icid);
3725
3726 return 0;
3727}
3728
3729static inline int l2cap_move_channel_confirm_rsp(struct l2cap_conn *conn,
3730 struct l2cap_cmd_hdr *cmd, u16 cmd_len, void *data)
3731{
3732 struct l2cap_move_chan_cfm_rsp *rsp = data;
3733 u16 icid;
3734
3735 if (cmd_len != sizeof(*rsp))
3736 return -EPROTO;
3737
3738 icid = le16_to_cpu(rsp->icid);
3739
3740 BT_DBG("icid %d", icid);
3741
3742 return 0;
3743}
3744
3745static inline int l2cap_check_conn_param(u16 min, u16 max, u16 latency,
3746 u16 to_multiplier)
3747{
3748 u16 max_latency;
3749
3750 if (min > max || min < 6 || max > 3200)
3751 return -EINVAL;
3752
3753 if (to_multiplier < 10 || to_multiplier > 3200)
3754 return -EINVAL;
3755
3756 if (max >= to_multiplier * 8)
3757 return -EINVAL;
3758
3759 max_latency = (to_multiplier * 8 / max) - 1;
3760 if (latency > 499 || latency > max_latency)
3761 return -EINVAL;
3762
3763 return 0;
3764}
3765
3766static inline int l2cap_conn_param_update_req(struct l2cap_conn *conn,
3767 struct l2cap_cmd_hdr *cmd, u8 *data)
3768{
3769 struct hci_conn *hcon = conn->hcon;
3770 struct l2cap_conn_param_update_req *req;
3771 struct l2cap_conn_param_update_rsp rsp;
3772 u16 min, max, latency, to_multiplier, cmd_len;
3773 int err;
3774
3775 if (!(hcon->link_mode & HCI_LM_MASTER))
3776 return -EINVAL;
3777
3778 cmd_len = __le16_to_cpu(cmd->len);
3779 if (cmd_len != sizeof(struct l2cap_conn_param_update_req))
3780 return -EPROTO;
3781
3782 req = (struct l2cap_conn_param_update_req *) data;
3783 min = __le16_to_cpu(req->min);
3784 max = __le16_to_cpu(req->max);
3785 latency = __le16_to_cpu(req->latency);
3786 to_multiplier = __le16_to_cpu(req->to_multiplier);
3787
3788 BT_DBG("min 0x%4.4x max 0x%4.4x latency: 0x%4.4x Timeout: 0x%4.4x",
3789 min, max, latency, to_multiplier);
3790
3791 memset(&rsp, 0, sizeof(rsp));
3792
3793 err = l2cap_check_conn_param(min, max, latency, to_multiplier);
3794 if (err)
3795 rsp.result = cpu_to_le16(L2CAP_CONN_PARAM_REJECTED);
3796 else
3797 rsp.result = cpu_to_le16(L2CAP_CONN_PARAM_ACCEPTED);
3798
3799 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONN_PARAM_UPDATE_RSP,
3800 sizeof(rsp), &rsp);
3801
3802 if (!err)
3803 hci_le_conn_update(hcon, min, max, latency, to_multiplier);
3804
3805 return 0;
3806}
3807
3808static inline int l2cap_bredr_sig_cmd(struct l2cap_conn *conn,
3809 struct l2cap_cmd_hdr *cmd, u16 cmd_len, u8 *data)
3810{
3811 int err = 0;
3812
3813 switch (cmd->code) {
3814 case L2CAP_COMMAND_REJ:
3815 l2cap_command_rej(conn, cmd, data);
3816 break;
3817
3818 case L2CAP_CONN_REQ:
3819 err = l2cap_connect_req(conn, cmd, data);
3820 break;
3821
3822 case L2CAP_CONN_RSP:
3823 err = l2cap_connect_rsp(conn, cmd, data);
3824 break;
3825
3826 case L2CAP_CONF_REQ:
3827 err = l2cap_config_req(conn, cmd, cmd_len, data);
3828 break;
3829
3830 case L2CAP_CONF_RSP:
3831 err = l2cap_config_rsp(conn, cmd, data);
3832 break;
3833
3834 case L2CAP_DISCONN_REQ:
3835 err = l2cap_disconnect_req(conn, cmd, data);
3836 break;
3837
3838 case L2CAP_DISCONN_RSP:
3839 err = l2cap_disconnect_rsp(conn, cmd, data);
3840 break;
3841
3842 case L2CAP_ECHO_REQ:
3843 l2cap_send_cmd(conn, cmd->ident, L2CAP_ECHO_RSP, cmd_len, data);
3844 break;
3845
3846 case L2CAP_ECHO_RSP:
3847 break;
3848
3849 case L2CAP_INFO_REQ:
3850 err = l2cap_information_req(conn, cmd, data);
3851 break;
3852
3853 case L2CAP_INFO_RSP:
3854 err = l2cap_information_rsp(conn, cmd, data);
3855 break;
3856
3857 case L2CAP_CREATE_CHAN_REQ:
3858 err = l2cap_create_channel_req(conn, cmd, cmd_len, data);
3859 break;
3860
3861 case L2CAP_CREATE_CHAN_RSP:
3862 err = l2cap_create_channel_rsp(conn, cmd, data);
3863 break;
3864
3865 case L2CAP_MOVE_CHAN_REQ:
3866 err = l2cap_move_channel_req(conn, cmd, cmd_len, data);
3867 break;
3868
3869 case L2CAP_MOVE_CHAN_RSP:
3870 err = l2cap_move_channel_rsp(conn, cmd, cmd_len, data);
3871 break;
3872
3873 case L2CAP_MOVE_CHAN_CFM:
3874 err = l2cap_move_channel_confirm(conn, cmd, cmd_len, data);
3875 break;
3876
3877 case L2CAP_MOVE_CHAN_CFM_RSP:
3878 err = l2cap_move_channel_confirm_rsp(conn, cmd, cmd_len, data);
3879 break;
3880
3881 default:
3882 BT_ERR("Unknown BR/EDR signaling command 0x%2.2x", cmd->code);
3883 err = -EINVAL;
3884 break;
3885 }
3886
3887 return err;
3888}
3889
3890static inline int l2cap_le_sig_cmd(struct l2cap_conn *conn,
3891 struct l2cap_cmd_hdr *cmd, u8 *data)
3892{
3893 switch (cmd->code) {
3894 case L2CAP_COMMAND_REJ:
3895 return 0;
3896
3897 case L2CAP_CONN_PARAM_UPDATE_REQ:
3898 return l2cap_conn_param_update_req(conn, cmd, data);
3899
3900 case L2CAP_CONN_PARAM_UPDATE_RSP:
3901 return 0;
3902
3903 default:
3904 BT_ERR("Unknown LE signaling command 0x%2.2x", cmd->code);
3905 return -EINVAL;
3906 }
3907}
3908
3909static inline void l2cap_sig_channel(struct l2cap_conn *conn,
3910 struct sk_buff *skb)
3911{
3912 u8 *data = skb->data;
3913 int len = skb->len;
3914 struct l2cap_cmd_hdr cmd;
3915 int err;
3916
3917 l2cap_raw_recv(conn, skb);
3918
3919 while (len >= L2CAP_CMD_HDR_SIZE) {
3920 u16 cmd_len;
3921 memcpy(&cmd, data, L2CAP_CMD_HDR_SIZE);
3922 data += L2CAP_CMD_HDR_SIZE;
3923 len -= L2CAP_CMD_HDR_SIZE;
3924
3925 cmd_len = le16_to_cpu(cmd.len);
3926
3927 BT_DBG("code 0x%2.2x len %d id 0x%2.2x", cmd.code, cmd_len, cmd.ident);
3928
3929 if (cmd_len > len || !cmd.ident) {
3930 BT_DBG("corrupted command");
3931 break;
3932 }
3933
3934 if (conn->hcon->type == LE_LINK)
3935 err = l2cap_le_sig_cmd(conn, &cmd, data);
3936 else
3937 err = l2cap_bredr_sig_cmd(conn, &cmd, cmd_len, data);
3938
3939 if (err) {
3940 struct l2cap_cmd_rej_unk rej;
3941
3942 BT_ERR("Wrong link type (%d)", err);
3943
3944 /* FIXME: Map err to a valid reason */
3945 rej.reason = cpu_to_le16(L2CAP_REJ_NOT_UNDERSTOOD);
3946 l2cap_send_cmd(conn, cmd.ident, L2CAP_COMMAND_REJ, sizeof(rej), &rej);
3947 }
3948
3949 data += cmd_len;
3950 len -= cmd_len;
3951 }
3952
3953 kfree_skb(skb);
3954}
3955
3956static int l2cap_check_fcs(struct l2cap_chan *chan, struct sk_buff *skb)
3957{
3958 u16 our_fcs, rcv_fcs;
3959 int hdr_size;
3960
3961 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
3962 hdr_size = L2CAP_EXT_HDR_SIZE;
3963 else
3964 hdr_size = L2CAP_ENH_HDR_SIZE;
3965
3966 if (chan->fcs == L2CAP_FCS_CRC16) {
3967 skb_trim(skb, skb->len - L2CAP_FCS_SIZE);
3968 rcv_fcs = get_unaligned_le16(skb->data + skb->len);
3969 our_fcs = crc16(0, skb->data - hdr_size, skb->len + hdr_size);
3970
3971 if (our_fcs != rcv_fcs)
3972 return -EBADMSG;
3973 }
3974 return 0;
3975}
3976
3977static inline void l2cap_send_i_or_rr_or_rnr(struct l2cap_chan *chan)
3978{
3979 u32 control = 0;
3980
3981 chan->frames_sent = 0;
3982
3983 control |= __set_reqseq(chan, chan->buffer_seq);
3984
3985 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
3986 control |= __set_ctrl_super(chan, L2CAP_SUPER_RNR);
3987 l2cap_send_sframe(chan, control);
3988 set_bit(CONN_RNR_SENT, &chan->conn_state);
3989 }
3990
3991 if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state))
3992 l2cap_retransmit_frames(chan);
3993
3994 l2cap_ertm_send(chan);
3995
3996 if (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state) &&
3997 chan->frames_sent == 0) {
3998 control |= __set_ctrl_super(chan, L2CAP_SUPER_RR);
3999 l2cap_send_sframe(chan, control);
4000 }
4001}
4002
4003static int l2cap_add_to_srej_queue(struct l2cap_chan *chan, struct sk_buff *skb, u16 tx_seq, u8 sar)
4004{
4005 struct sk_buff *next_skb;
4006 int tx_seq_offset, next_tx_seq_offset;
4007
4008 bt_cb(skb)->control.txseq = tx_seq;
4009 bt_cb(skb)->control.sar = sar;
4010
4011 next_skb = skb_peek(&chan->srej_q);
4012
4013 tx_seq_offset = __seq_offset(chan, tx_seq, chan->buffer_seq);
4014
4015 while (next_skb) {
4016 if (bt_cb(next_skb)->control.txseq == tx_seq)
4017 return -EINVAL;
4018
4019 next_tx_seq_offset = __seq_offset(chan,
4020 bt_cb(next_skb)->control.txseq, chan->buffer_seq);
4021
4022 if (next_tx_seq_offset > tx_seq_offset) {
4023 __skb_queue_before(&chan->srej_q, next_skb, skb);
4024 return 0;
4025 }
4026
4027 if (skb_queue_is_last(&chan->srej_q, next_skb))
4028 next_skb = NULL;
4029 else
4030 next_skb = skb_queue_next(&chan->srej_q, next_skb);
4031 }
4032
4033 __skb_queue_tail(&chan->srej_q, skb);
4034
4035 return 0;
4036}
4037
4038static void append_skb_frag(struct sk_buff *skb,
4039 struct sk_buff *new_frag, struct sk_buff **last_frag)
4040{
4041 /* skb->len reflects data in skb as well as all fragments
4042 * skb->data_len reflects only data in fragments
4043 */
4044 if (!skb_has_frag_list(skb))
4045 skb_shinfo(skb)->frag_list = new_frag;
4046
4047 new_frag->next = NULL;
4048
4049 (*last_frag)->next = new_frag;
4050 *last_frag = new_frag;
4051
4052 skb->len += new_frag->len;
4053 skb->data_len += new_frag->len;
4054 skb->truesize += new_frag->truesize;
4055}
4056
4057static int l2cap_reassemble_sdu(struct l2cap_chan *chan, struct sk_buff *skb, u32 control)
4058{
4059 int err = -EINVAL;
4060
4061 switch (__get_ctrl_sar(chan, control)) {
4062 case L2CAP_SAR_UNSEGMENTED:
4063 if (chan->sdu)
4064 break;
4065
4066 err = chan->ops->recv(chan->data, skb);
4067 break;
4068
4069 case L2CAP_SAR_START:
4070 if (chan->sdu)
4071 break;
4072
4073 chan->sdu_len = get_unaligned_le16(skb->data);
4074 skb_pull(skb, L2CAP_SDULEN_SIZE);
4075
4076 if (chan->sdu_len > chan->imtu) {
4077 err = -EMSGSIZE;
4078 break;
4079 }
4080
4081 if (skb->len >= chan->sdu_len)
4082 break;
4083
4084 chan->sdu = skb;
4085 chan->sdu_last_frag = skb;
4086
4087 skb = NULL;
4088 err = 0;
4089 break;
4090
4091 case L2CAP_SAR_CONTINUE:
4092 if (!chan->sdu)
4093 break;
4094
4095 append_skb_frag(chan->sdu, skb,
4096 &chan->sdu_last_frag);
4097 skb = NULL;
4098
4099 if (chan->sdu->len >= chan->sdu_len)
4100 break;
4101
4102 err = 0;
4103 break;
4104
4105 case L2CAP_SAR_END:
4106 if (!chan->sdu)
4107 break;
4108
4109 append_skb_frag(chan->sdu, skb,
4110 &chan->sdu_last_frag);
4111 skb = NULL;
4112
4113 if (chan->sdu->len != chan->sdu_len)
4114 break;
4115
4116 err = chan->ops->recv(chan->data, chan->sdu);
4117
4118 if (!err) {
4119 /* Reassembly complete */
4120 chan->sdu = NULL;
4121 chan->sdu_last_frag = NULL;
4122 chan->sdu_len = 0;
4123 }
4124 break;
4125 }
4126
4127 if (err) {
4128 kfree_skb(skb);
4129 kfree_skb(chan->sdu);
4130 chan->sdu = NULL;
4131 chan->sdu_last_frag = NULL;
4132 chan->sdu_len = 0;
4133 }
4134
4135 return err;
4136}
4137
4138static void l2cap_ertm_enter_local_busy(struct l2cap_chan *chan)
4139{
4140 BT_DBG("chan %p, Enter local busy", chan);
4141
4142 set_bit(CONN_LOCAL_BUSY, &chan->conn_state);
4143 l2cap_seq_list_clear(&chan->srej_list);
4144
4145 __set_ack_timer(chan);
4146}
4147
4148static void l2cap_ertm_exit_local_busy(struct l2cap_chan *chan)
4149{
4150 u32 control;
4151
4152 if (!test_bit(CONN_RNR_SENT, &chan->conn_state))
4153 goto done;
4154
4155 control = __set_reqseq(chan, chan->buffer_seq);
4156 control |= __set_ctrl_poll(chan);
4157 control |= __set_ctrl_super(chan, L2CAP_SUPER_RR);
4158 l2cap_send_sframe(chan, control);
4159 chan->retry_count = 1;
4160
4161 __clear_retrans_timer(chan);
4162 __set_monitor_timer(chan);
4163
4164 set_bit(CONN_WAIT_F, &chan->conn_state);
4165
4166done:
4167 clear_bit(CONN_LOCAL_BUSY, &chan->conn_state);
4168 clear_bit(CONN_RNR_SENT, &chan->conn_state);
4169
4170 BT_DBG("chan %p, Exit local busy", chan);
4171}
4172
4173void l2cap_chan_busy(struct l2cap_chan *chan, int busy)
4174{
4175 if (chan->mode == L2CAP_MODE_ERTM) {
4176 if (busy)
4177 l2cap_ertm_enter_local_busy(chan);
4178 else
4179 l2cap_ertm_exit_local_busy(chan);
4180 }
4181}
4182
4183static void l2cap_check_srej_gap(struct l2cap_chan *chan, u16 tx_seq)
4184{
4185 struct sk_buff *skb;
4186 u32 control;
4187
4188 while ((skb = skb_peek(&chan->srej_q)) &&
4189 !test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
4190 int err;
4191
4192 if (bt_cb(skb)->control.txseq != tx_seq)
4193 break;
4194
4195 skb = skb_dequeue(&chan->srej_q);
4196 control = __set_ctrl_sar(chan, bt_cb(skb)->control.sar);
4197 err = l2cap_reassemble_sdu(chan, skb, control);
4198
4199 if (err < 0) {
4200 l2cap_send_disconn_req(chan->conn, chan, ECONNRESET);
4201 break;
4202 }
4203
4204 chan->buffer_seq_srej = __next_seq(chan, chan->buffer_seq_srej);
4205 tx_seq = __next_seq(chan, tx_seq);
4206 }
4207}
4208
4209static void l2cap_resend_srejframe(struct l2cap_chan *chan, u16 tx_seq)
4210{
4211 struct srej_list *l, *tmp;
4212 u32 control;
4213
4214 list_for_each_entry_safe(l, tmp, &chan->srej_l, list) {
4215 if (l->tx_seq == tx_seq) {
4216 list_del(&l->list);
4217 kfree(l);
4218 return;
4219 }
4220 control = __set_ctrl_super(chan, L2CAP_SUPER_SREJ);
4221 control |= __set_reqseq(chan, l->tx_seq);
4222 l2cap_send_sframe(chan, control);
4223 list_del(&l->list);
4224 list_add_tail(&l->list, &chan->srej_l);
4225 }
4226}
4227
4228static int l2cap_send_srejframe(struct l2cap_chan *chan, u16 tx_seq)
4229{
4230 struct srej_list *new;
4231 u32 control;
4232
4233 while (tx_seq != chan->expected_tx_seq) {
4234 control = __set_ctrl_super(chan, L2CAP_SUPER_SREJ);
4235 control |= __set_reqseq(chan, chan->expected_tx_seq);
4236 l2cap_seq_list_append(&chan->srej_list, chan->expected_tx_seq);
4237 l2cap_send_sframe(chan, control);
4238
4239 new = kzalloc(sizeof(struct srej_list), GFP_ATOMIC);
4240 if (!new)
4241 return -ENOMEM;
4242
4243 new->tx_seq = chan->expected_tx_seq;
4244
4245 chan->expected_tx_seq = __next_seq(chan, chan->expected_tx_seq);
4246
4247 list_add_tail(&new->list, &chan->srej_l);
4248 }
4249
4250 chan->expected_tx_seq = __next_seq(chan, chan->expected_tx_seq);
4251
4252 return 0;
4253}
4254
4255static inline int l2cap_data_channel_iframe(struct l2cap_chan *chan, u32 rx_control, struct sk_buff *skb)
4256{
4257 u16 tx_seq = __get_txseq(chan, rx_control);
4258 u16 req_seq = __get_reqseq(chan, rx_control);
4259 u8 sar = __get_ctrl_sar(chan, rx_control);
4260 int tx_seq_offset, expected_tx_seq_offset;
4261 int num_to_ack = (chan->tx_win/6) + 1;
4262 int err = 0;
4263
4264 BT_DBG("chan %p len %d tx_seq %d rx_control 0x%8.8x", chan, skb->len,
4265 tx_seq, rx_control);
4266
4267 if (__is_ctrl_final(chan, rx_control) &&
4268 test_bit(CONN_WAIT_F, &chan->conn_state)) {
4269 __clear_monitor_timer(chan);
4270 if (chan->unacked_frames > 0)
4271 __set_retrans_timer(chan);
4272 clear_bit(CONN_WAIT_F, &chan->conn_state);
4273 }
4274
4275 chan->expected_ack_seq = req_seq;
4276 l2cap_drop_acked_frames(chan);
4277
4278 tx_seq_offset = __seq_offset(chan, tx_seq, chan->buffer_seq);
4279
4280 /* invalid tx_seq */
4281 if (tx_seq_offset >= chan->tx_win) {
4282 l2cap_send_disconn_req(chan->conn, chan, ECONNRESET);
4283 goto drop;
4284 }
4285
4286 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
4287 if (!test_bit(CONN_RNR_SENT, &chan->conn_state))
4288 l2cap_send_ack(chan);
4289 goto drop;
4290 }
4291
4292 if (tx_seq == chan->expected_tx_seq)
4293 goto expected;
4294
4295 if (test_bit(CONN_SREJ_SENT, &chan->conn_state)) {
4296 struct srej_list *first;
4297
4298 first = list_first_entry(&chan->srej_l,
4299 struct srej_list, list);
4300 if (tx_seq == first->tx_seq) {
4301 l2cap_add_to_srej_queue(chan, skb, tx_seq, sar);
4302 l2cap_check_srej_gap(chan, tx_seq);
4303
4304 list_del(&first->list);
4305 kfree(first);
4306
4307 if (list_empty(&chan->srej_l)) {
4308 chan->buffer_seq = chan->buffer_seq_srej;
4309 clear_bit(CONN_SREJ_SENT, &chan->conn_state);
4310 l2cap_send_ack(chan);
4311 BT_DBG("chan %p, Exit SREJ_SENT", chan);
4312 }
4313 } else {
4314 struct srej_list *l;
4315
4316 /* duplicated tx_seq */
4317 if (l2cap_add_to_srej_queue(chan, skb, tx_seq, sar) < 0)
4318 goto drop;
4319
4320 list_for_each_entry(l, &chan->srej_l, list) {
4321 if (l->tx_seq == tx_seq) {
4322 l2cap_resend_srejframe(chan, tx_seq);
4323 return 0;
4324 }
4325 }
4326
4327 err = l2cap_send_srejframe(chan, tx_seq);
4328 if (err < 0) {
4329 l2cap_send_disconn_req(chan->conn, chan, -err);
4330 return err;
4331 }
4332 }
4333 } else {
4334 expected_tx_seq_offset = __seq_offset(chan,
4335 chan->expected_tx_seq, chan->buffer_seq);
4336
4337 /* duplicated tx_seq */
4338 if (tx_seq_offset < expected_tx_seq_offset)
4339 goto drop;
4340
4341 set_bit(CONN_SREJ_SENT, &chan->conn_state);
4342
4343 BT_DBG("chan %p, Enter SREJ", chan);
4344
4345 INIT_LIST_HEAD(&chan->srej_l);
4346 chan->buffer_seq_srej = chan->buffer_seq;
4347
4348 __skb_queue_head_init(&chan->srej_q);
4349 l2cap_add_to_srej_queue(chan, skb, tx_seq, sar);
4350
4351 /* Set P-bit only if there are some I-frames to ack. */
4352 if (__clear_ack_timer(chan))
4353 set_bit(CONN_SEND_PBIT, &chan->conn_state);
4354
4355 err = l2cap_send_srejframe(chan, tx_seq);
4356 if (err < 0) {
4357 l2cap_send_disconn_req(chan->conn, chan, -err);
4358 return err;
4359 }
4360 }
4361 return 0;
4362
4363expected:
4364 chan->expected_tx_seq = __next_seq(chan, chan->expected_tx_seq);
4365
4366 if (test_bit(CONN_SREJ_SENT, &chan->conn_state)) {
4367 bt_cb(skb)->control.txseq = tx_seq;
4368 bt_cb(skb)->control.sar = sar;
4369 __skb_queue_tail(&chan->srej_q, skb);
4370 return 0;
4371 }
4372
4373 err = l2cap_reassemble_sdu(chan, skb, rx_control);
4374 chan->buffer_seq = __next_seq(chan, chan->buffer_seq);
4375
4376 if (err < 0) {
4377 l2cap_send_disconn_req(chan->conn, chan, ECONNRESET);
4378 return err;
4379 }
4380
4381 if (__is_ctrl_final(chan, rx_control)) {
4382 if (!test_and_clear_bit(CONN_REJ_ACT, &chan->conn_state))
4383 l2cap_retransmit_frames(chan);
4384 }
4385
4386
4387 chan->num_acked = (chan->num_acked + 1) % num_to_ack;
4388 if (chan->num_acked == num_to_ack - 1)
4389 l2cap_send_ack(chan);
4390 else
4391 __set_ack_timer(chan);
4392
4393 return 0;
4394
4395drop:
4396 kfree_skb(skb);
4397 return 0;
4398}
4399
4400static inline void l2cap_data_channel_rrframe(struct l2cap_chan *chan, u32 rx_control)
4401{
4402 BT_DBG("chan %p, req_seq %d ctrl 0x%8.8x", chan,
4403 __get_reqseq(chan, rx_control), rx_control);
4404
4405 chan->expected_ack_seq = __get_reqseq(chan, rx_control);
4406 l2cap_drop_acked_frames(chan);
4407
4408 if (__is_ctrl_poll(chan, rx_control)) {
4409 set_bit(CONN_SEND_FBIT, &chan->conn_state);
4410 if (test_bit(CONN_SREJ_SENT, &chan->conn_state)) {
4411 if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state) &&
4412 (chan->unacked_frames > 0))
4413 __set_retrans_timer(chan);
4414
4415 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
4416 l2cap_send_srejtail(chan);
4417 } else {
4418 l2cap_send_i_or_rr_or_rnr(chan);
4419 }
4420
4421 } else if (__is_ctrl_final(chan, rx_control)) {
4422 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
4423
4424 if (!test_and_clear_bit(CONN_REJ_ACT, &chan->conn_state))
4425 l2cap_retransmit_frames(chan);
4426
4427 } else {
4428 if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state) &&
4429 (chan->unacked_frames > 0))
4430 __set_retrans_timer(chan);
4431
4432 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
4433 if (test_bit(CONN_SREJ_SENT, &chan->conn_state))
4434 l2cap_send_ack(chan);
4435 else
4436 l2cap_ertm_send(chan);
4437 }
4438}
4439
4440static inline void l2cap_data_channel_rejframe(struct l2cap_chan *chan, u32 rx_control)
4441{
4442 u16 tx_seq = __get_reqseq(chan, rx_control);
4443
4444 BT_DBG("chan %p, req_seq %d ctrl 0x%8.8x", chan, tx_seq, rx_control);
4445
4446 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
4447
4448 chan->expected_ack_seq = tx_seq;
4449 l2cap_drop_acked_frames(chan);
4450
4451 if (__is_ctrl_final(chan, rx_control)) {
4452 if (!test_and_clear_bit(CONN_REJ_ACT, &chan->conn_state))
4453 l2cap_retransmit_frames(chan);
4454 } else {
4455 l2cap_retransmit_frames(chan);
4456
4457 if (test_bit(CONN_WAIT_F, &chan->conn_state))
4458 set_bit(CONN_REJ_ACT, &chan->conn_state);
4459 }
4460}
4461static inline void l2cap_data_channel_srejframe(struct l2cap_chan *chan, u32 rx_control)
4462{
4463 u16 tx_seq = __get_reqseq(chan, rx_control);
4464
4465 BT_DBG("chan %p, req_seq %d ctrl 0x%8.8x", chan, tx_seq, rx_control);
4466
4467 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
4468
4469 if (__is_ctrl_poll(chan, rx_control)) {
4470 chan->expected_ack_seq = tx_seq;
4471 l2cap_drop_acked_frames(chan);
4472
4473 set_bit(CONN_SEND_FBIT, &chan->conn_state);
4474 l2cap_retransmit_one_frame(chan, tx_seq);
4475
4476 l2cap_ertm_send(chan);
4477
4478 if (test_bit(CONN_WAIT_F, &chan->conn_state)) {
4479 chan->srej_save_reqseq = tx_seq;
4480 set_bit(CONN_SREJ_ACT, &chan->conn_state);
4481 }
4482 } else if (__is_ctrl_final(chan, rx_control)) {
4483 if (test_bit(CONN_SREJ_ACT, &chan->conn_state) &&
4484 chan->srej_save_reqseq == tx_seq)
4485 clear_bit(CONN_SREJ_ACT, &chan->conn_state);
4486 else
4487 l2cap_retransmit_one_frame(chan, tx_seq);
4488 } else {
4489 l2cap_retransmit_one_frame(chan, tx_seq);
4490 if (test_bit(CONN_WAIT_F, &chan->conn_state)) {
4491 chan->srej_save_reqseq = tx_seq;
4492 set_bit(CONN_SREJ_ACT, &chan->conn_state);
4493 }
4494 }
4495}
4496
4497static inline void l2cap_data_channel_rnrframe(struct l2cap_chan *chan, u32 rx_control)
4498{
4499 u16 tx_seq = __get_reqseq(chan, rx_control);
4500
4501 BT_DBG("chan %p, req_seq %d ctrl 0x%8.8x", chan, tx_seq, rx_control);
4502
4503 set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
4504 chan->expected_ack_seq = tx_seq;
4505 l2cap_drop_acked_frames(chan);
4506
4507 if (__is_ctrl_poll(chan, rx_control))
4508 set_bit(CONN_SEND_FBIT, &chan->conn_state);
4509
4510 if (!test_bit(CONN_SREJ_SENT, &chan->conn_state)) {
4511 __clear_retrans_timer(chan);
4512 if (__is_ctrl_poll(chan, rx_control))
4513 l2cap_send_rr_or_rnr(chan, L2CAP_CTRL_FINAL);
4514 return;
4515 }
4516
4517 if (__is_ctrl_poll(chan, rx_control)) {
4518 l2cap_send_srejtail(chan);
4519 } else {
4520 rx_control = __set_ctrl_super(chan, L2CAP_SUPER_RR);
4521 l2cap_send_sframe(chan, rx_control);
4522 }
4523}
4524
4525static inline int l2cap_data_channel_sframe(struct l2cap_chan *chan, u32 rx_control, struct sk_buff *skb)
4526{
4527 BT_DBG("chan %p rx_control 0x%8.8x len %d", chan, rx_control, skb->len);
4528
4529 if (__is_ctrl_final(chan, rx_control) &&
4530 test_bit(CONN_WAIT_F, &chan->conn_state)) {
4531 __clear_monitor_timer(chan);
4532 if (chan->unacked_frames > 0)
4533 __set_retrans_timer(chan);
4534 clear_bit(CONN_WAIT_F, &chan->conn_state);
4535 }
4536
4537 switch (__get_ctrl_super(chan, rx_control)) {
4538 case L2CAP_SUPER_RR:
4539 l2cap_data_channel_rrframe(chan, rx_control);
4540 break;
4541
4542 case L2CAP_SUPER_REJ:
4543 l2cap_data_channel_rejframe(chan, rx_control);
4544 break;
4545
4546 case L2CAP_SUPER_SREJ:
4547 l2cap_data_channel_srejframe(chan, rx_control);
4548 break;
4549
4550 case L2CAP_SUPER_RNR:
4551 l2cap_data_channel_rnrframe(chan, rx_control);
4552 break;
4553 }
4554
4555 kfree_skb(skb);
4556 return 0;
4557}
4558
4559static int l2cap_ertm_data_rcv(struct l2cap_chan *chan, struct sk_buff *skb)
4560{
4561 u32 control;
4562 u16 req_seq;
4563 int len, next_tx_seq_offset, req_seq_offset;
4564
4565 __unpack_control(chan, skb);
4566
4567 control = __get_control(chan, skb->data);
4568 skb_pull(skb, __ctrl_size(chan));
4569 len = skb->len;
4570
4571 /*
4572 * We can just drop the corrupted I-frame here.
4573 * Receiver will miss it and start proper recovery
4574 * procedures and ask retransmission.
4575 */
4576 if (l2cap_check_fcs(chan, skb))
4577 goto drop;
4578
4579 if (__is_sar_start(chan, control) && !__is_sframe(chan, control))
4580 len -= L2CAP_SDULEN_SIZE;
4581
4582 if (chan->fcs == L2CAP_FCS_CRC16)
4583 len -= L2CAP_FCS_SIZE;
4584
4585 if (len > chan->mps) {
4586 l2cap_send_disconn_req(chan->conn, chan, ECONNRESET);
4587 goto drop;
4588 }
4589
4590 req_seq = __get_reqseq(chan, control);
4591
4592 req_seq_offset = __seq_offset(chan, req_seq, chan->expected_ack_seq);
4593
4594 next_tx_seq_offset = __seq_offset(chan, chan->next_tx_seq,
4595 chan->expected_ack_seq);
4596
4597 /* check for invalid req-seq */
4598 if (req_seq_offset > next_tx_seq_offset) {
4599 l2cap_send_disconn_req(chan->conn, chan, ECONNRESET);
4600 goto drop;
4601 }
4602
4603 if (!__is_sframe(chan, control)) {
4604 if (len < 0) {
4605 l2cap_send_disconn_req(chan->conn, chan, ECONNRESET);
4606 goto drop;
4607 }
4608
4609 l2cap_data_channel_iframe(chan, control, skb);
4610 } else {
4611 if (len != 0) {
4612 BT_ERR("%d", len);
4613 l2cap_send_disconn_req(chan->conn, chan, ECONNRESET);
4614 goto drop;
4615 }
4616
4617 l2cap_data_channel_sframe(chan, control, skb);
4618 }
4619
4620 return 0;
4621
4622drop:
4623 kfree_skb(skb);
4624 return 0;
4625}
4626
4627static inline int l2cap_data_channel(struct l2cap_conn *conn, u16 cid, struct sk_buff *skb)
4628{
4629 struct l2cap_chan *chan;
4630 u32 control;
4631 u16 tx_seq;
4632 int len;
4633
4634 chan = l2cap_get_chan_by_scid(conn, cid);
4635 if (!chan) {
4636 BT_DBG("unknown cid 0x%4.4x", cid);
4637 /* Drop packet and return */
4638 kfree_skb(skb);
4639 return 0;
4640 }
4641
4642 BT_DBG("chan %p, len %d", chan, skb->len);
4643
4644 if (chan->state != BT_CONNECTED)
4645 goto drop;
4646
4647 switch (chan->mode) {
4648 case L2CAP_MODE_BASIC:
4649 /* If socket recv buffers overflows we drop data here
4650 * which is *bad* because L2CAP has to be reliable.
4651 * But we don't have any other choice. L2CAP doesn't
4652 * provide flow control mechanism. */
4653
4654 if (chan->imtu < skb->len)
4655 goto drop;
4656
4657 if (!chan->ops->recv(chan->data, skb))
4658 goto done;
4659 break;
4660
4661 case L2CAP_MODE_ERTM:
4662 l2cap_ertm_data_rcv(chan, skb);
4663
4664 goto done;
4665
4666 case L2CAP_MODE_STREAMING:
4667 control = __get_control(chan, skb->data);
4668 skb_pull(skb, __ctrl_size(chan));
4669 len = skb->len;
4670
4671 if (l2cap_check_fcs(chan, skb))
4672 goto drop;
4673
4674 if (__is_sar_start(chan, control))
4675 len -= L2CAP_SDULEN_SIZE;
4676
4677 if (chan->fcs == L2CAP_FCS_CRC16)
4678 len -= L2CAP_FCS_SIZE;
4679
4680 if (len > chan->mps || len < 0 || __is_sframe(chan, control))
4681 goto drop;
4682
4683 tx_seq = __get_txseq(chan, control);
4684
4685 if (chan->expected_tx_seq != tx_seq) {
4686 /* Frame(s) missing - must discard partial SDU */
4687 kfree_skb(chan->sdu);
4688 chan->sdu = NULL;
4689 chan->sdu_last_frag = NULL;
4690 chan->sdu_len = 0;
4691
4692 /* TODO: Notify userland of missing data */
4693 }
4694
4695 chan->expected_tx_seq = __next_seq(chan, tx_seq);
4696
4697 if (l2cap_reassemble_sdu(chan, skb, control) == -EMSGSIZE)
4698 l2cap_send_disconn_req(chan->conn, chan, ECONNRESET);
4699
4700 goto done;
4701
4702 default:
4703 BT_DBG("chan %p: bad mode 0x%2.2x", chan, chan->mode);
4704 break;
4705 }
4706
4707drop:
4708 kfree_skb(skb);
4709
4710done:
4711 l2cap_chan_unlock(chan);
4712
4713 return 0;
4714}
4715
4716static inline int l2cap_conless_channel(struct l2cap_conn *conn, __le16 psm, struct sk_buff *skb)
4717{
4718 struct l2cap_chan *chan;
4719
4720 chan = l2cap_global_chan_by_psm(0, psm, conn->src, conn->dst);
4721 if (!chan)
4722 goto drop;
4723
4724 BT_DBG("chan %p, len %d", chan, skb->len);
4725
4726 if (chan->state != BT_BOUND && chan->state != BT_CONNECTED)
4727 goto drop;
4728
4729 if (chan->imtu < skb->len)
4730 goto drop;
4731
4732 if (!chan->ops->recv(chan->data, skb))
4733 return 0;
4734
4735drop:
4736 kfree_skb(skb);
4737
4738 return 0;
4739}
4740
4741static inline int l2cap_att_channel(struct l2cap_conn *conn, u16 cid,
4742 struct sk_buff *skb)
4743{
4744 struct l2cap_chan *chan;
4745
4746 chan = l2cap_global_chan_by_scid(0, cid, conn->src, conn->dst);
4747 if (!chan)
4748 goto drop;
4749
4750 BT_DBG("chan %p, len %d", chan, skb->len);
4751
4752 if (chan->state != BT_BOUND && chan->state != BT_CONNECTED)
4753 goto drop;
4754
4755 if (chan->imtu < skb->len)
4756 goto drop;
4757
4758 if (!chan->ops->recv(chan->data, skb))
4759 return 0;
4760
4761drop:
4762 kfree_skb(skb);
4763
4764 return 0;
4765}
4766
4767static void l2cap_recv_frame(struct l2cap_conn *conn, struct sk_buff *skb)
4768{
4769 struct l2cap_hdr *lh = (void *) skb->data;
4770 u16 cid, len;
4771 __le16 psm;
4772
4773 skb_pull(skb, L2CAP_HDR_SIZE);
4774 cid = __le16_to_cpu(lh->cid);
4775 len = __le16_to_cpu(lh->len);
4776
4777 if (len != skb->len) {
4778 kfree_skb(skb);
4779 return;
4780 }
4781
4782 BT_DBG("len %d, cid 0x%4.4x", len, cid);
4783
4784 switch (cid) {
4785 case L2CAP_CID_LE_SIGNALING:
4786 case L2CAP_CID_SIGNALING:
4787 l2cap_sig_channel(conn, skb);
4788 break;
4789
4790 case L2CAP_CID_CONN_LESS:
4791 psm = get_unaligned((__le16 *) skb->data);
4792 skb_pull(skb, 2);
4793 l2cap_conless_channel(conn, psm, skb);
4794 break;
4795
4796 case L2CAP_CID_LE_DATA:
4797 l2cap_att_channel(conn, cid, skb);
4798 break;
4799
4800 case L2CAP_CID_SMP:
4801 if (smp_sig_channel(conn, skb))
4802 l2cap_conn_del(conn->hcon, EACCES);
4803 break;
4804
4805 default:
4806 l2cap_data_channel(conn, cid, skb);
4807 break;
4808 }
4809}
4810
4811/* ---- L2CAP interface with lower layer (HCI) ---- */
4812
4813int l2cap_connect_ind(struct hci_dev *hdev, bdaddr_t *bdaddr)
4814{
4815 int exact = 0, lm1 = 0, lm2 = 0;
4816 struct l2cap_chan *c;
4817
4818 BT_DBG("hdev %s, bdaddr %s", hdev->name, batostr(bdaddr));
4819
4820 /* Find listening sockets and check their link_mode */
4821 read_lock(&chan_list_lock);
4822 list_for_each_entry(c, &chan_list, global_l) {
4823 struct sock *sk = c->sk;
4824
4825 if (c->state != BT_LISTEN)
4826 continue;
4827
4828 if (!bacmp(&bt_sk(sk)->src, &hdev->bdaddr)) {
4829 lm1 |= HCI_LM_ACCEPT;
4830 if (test_bit(FLAG_ROLE_SWITCH, &c->flags))
4831 lm1 |= HCI_LM_MASTER;
4832 exact++;
4833 } else if (!bacmp(&bt_sk(sk)->src, BDADDR_ANY)) {
4834 lm2 |= HCI_LM_ACCEPT;
4835 if (test_bit(FLAG_ROLE_SWITCH, &c->flags))
4836 lm2 |= HCI_LM_MASTER;
4837 }
4838 }
4839 read_unlock(&chan_list_lock);
4840
4841 return exact ? lm1 : lm2;
4842}
4843
4844int l2cap_connect_cfm(struct hci_conn *hcon, u8 status)
4845{
4846 struct l2cap_conn *conn;
4847
4848 BT_DBG("hcon %p bdaddr %s status %d", hcon, batostr(&hcon->dst), status);
4849
4850 if (!status) {
4851 conn = l2cap_conn_add(hcon, status);
4852 if (conn)
4853 l2cap_conn_ready(conn);
4854 } else
4855 l2cap_conn_del(hcon, bt_to_errno(status));
4856
4857 return 0;
4858}
4859
4860int l2cap_disconn_ind(struct hci_conn *hcon)
4861{
4862 struct l2cap_conn *conn = hcon->l2cap_data;
4863
4864 BT_DBG("hcon %p", hcon);
4865
4866 if (!conn)
4867 return HCI_ERROR_REMOTE_USER_TERM;
4868 return conn->disc_reason;
4869}
4870
4871int l2cap_disconn_cfm(struct hci_conn *hcon, u8 reason)
4872{
4873 BT_DBG("hcon %p reason %d", hcon, reason);
4874
4875 l2cap_conn_del(hcon, bt_to_errno(reason));
4876 return 0;
4877}
4878
4879static inline void l2cap_check_encryption(struct l2cap_chan *chan, u8 encrypt)
4880{
4881 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED)
4882 return;
4883
4884 if (encrypt == 0x00) {
4885 if (chan->sec_level == BT_SECURITY_MEDIUM) {
4886 __set_chan_timer(chan, L2CAP_ENC_TIMEOUT);
4887 } else if (chan->sec_level == BT_SECURITY_HIGH)
4888 l2cap_chan_close(chan, ECONNREFUSED);
4889 } else {
4890 if (chan->sec_level == BT_SECURITY_MEDIUM)
4891 __clear_chan_timer(chan);
4892 }
4893}
4894
4895int l2cap_security_cfm(struct hci_conn *hcon, u8 status, u8 encrypt)
4896{
4897 struct l2cap_conn *conn = hcon->l2cap_data;
4898 struct l2cap_chan *chan;
4899
4900 if (!conn)
4901 return 0;
4902
4903 BT_DBG("conn %p", conn);
4904
4905 if (hcon->type == LE_LINK) {
4906 if (!status && encrypt)
4907 smp_distribute_keys(conn, 0);
4908 cancel_delayed_work(&conn->security_timer);
4909 }
4910
4911 mutex_lock(&conn->chan_lock);
4912
4913 list_for_each_entry(chan, &conn->chan_l, list) {
4914 l2cap_chan_lock(chan);
4915
4916 BT_DBG("chan->scid %d", chan->scid);
4917
4918 if (chan->scid == L2CAP_CID_LE_DATA) {
4919 if (!status && encrypt) {
4920 chan->sec_level = hcon->sec_level;
4921 l2cap_chan_ready(chan);
4922 }
4923
4924 l2cap_chan_unlock(chan);
4925 continue;
4926 }
4927
4928 if (test_bit(CONF_CONNECT_PEND, &chan->conf_state)) {
4929 l2cap_chan_unlock(chan);
4930 continue;
4931 }
4932
4933 if (!status && (chan->state == BT_CONNECTED ||
4934 chan->state == BT_CONFIG)) {
4935 struct sock *sk = chan->sk;
4936
4937 clear_bit(BT_SK_SUSPEND, &bt_sk(sk)->flags);
4938 sk->sk_state_change(sk);
4939
4940 l2cap_check_encryption(chan, encrypt);
4941 l2cap_chan_unlock(chan);
4942 continue;
4943 }
4944
4945 if (chan->state == BT_CONNECT) {
4946 if (!status) {
4947 l2cap_send_conn_req(chan);
4948 } else {
4949 __set_chan_timer(chan, L2CAP_DISC_TIMEOUT);
4950 }
4951 } else if (chan->state == BT_CONNECT2) {
4952 struct sock *sk = chan->sk;
4953 struct l2cap_conn_rsp rsp;
4954 __u16 res, stat;
4955
4956 lock_sock(sk);
4957
4958 if (!status) {
4959 if (test_bit(BT_SK_DEFER_SETUP,
4960 &bt_sk(sk)->flags)) {
4961 struct sock *parent = bt_sk(sk)->parent;
4962 res = L2CAP_CR_PEND;
4963 stat = L2CAP_CS_AUTHOR_PEND;
4964 if (parent)
4965 parent->sk_data_ready(parent, 0);
4966 } else {
4967 __l2cap_state_change(chan, BT_CONFIG);
4968 res = L2CAP_CR_SUCCESS;
4969 stat = L2CAP_CS_NO_INFO;
4970 }
4971 } else {
4972 __l2cap_state_change(chan, BT_DISCONN);
4973 __set_chan_timer(chan, L2CAP_DISC_TIMEOUT);
4974 res = L2CAP_CR_SEC_BLOCK;
4975 stat = L2CAP_CS_NO_INFO;
4976 }
4977
4978 release_sock(sk);
4979
4980 rsp.scid = cpu_to_le16(chan->dcid);
4981 rsp.dcid = cpu_to_le16(chan->scid);
4982 rsp.result = cpu_to_le16(res);
4983 rsp.status = cpu_to_le16(stat);
4984 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP,
4985 sizeof(rsp), &rsp);
4986 }
4987
4988 l2cap_chan_unlock(chan);
4989 }
4990
4991 mutex_unlock(&conn->chan_lock);
4992
4993 return 0;
4994}
4995
4996int l2cap_recv_acldata(struct hci_conn *hcon, struct sk_buff *skb, u16 flags)
4997{
4998 struct l2cap_conn *conn = hcon->l2cap_data;
4999
5000 if (!conn)
5001 conn = l2cap_conn_add(hcon, 0);
5002
5003 if (!conn)
5004 goto drop;
5005
5006 BT_DBG("conn %p len %d flags 0x%x", conn, skb->len, flags);
5007
5008 if (!(flags & ACL_CONT)) {
5009 struct l2cap_hdr *hdr;
5010 int len;
5011
5012 if (conn->rx_len) {
5013 BT_ERR("Unexpected start frame (len %d)", skb->len);
5014 kfree_skb(conn->rx_skb);
5015 conn->rx_skb = NULL;
5016 conn->rx_len = 0;
5017 l2cap_conn_unreliable(conn, ECOMM);
5018 }
5019
5020 /* Start fragment always begin with Basic L2CAP header */
5021 if (skb->len < L2CAP_HDR_SIZE) {
5022 BT_ERR("Frame is too short (len %d)", skb->len);
5023 l2cap_conn_unreliable(conn, ECOMM);
5024 goto drop;
5025 }
5026
5027 hdr = (struct l2cap_hdr *) skb->data;
5028 len = __le16_to_cpu(hdr->len) + L2CAP_HDR_SIZE;
5029
5030 if (len == skb->len) {
5031 /* Complete frame received */
5032 l2cap_recv_frame(conn, skb);
5033 return 0;
5034 }
5035
5036 BT_DBG("Start: total len %d, frag len %d", len, skb->len);
5037
5038 if (skb->len > len) {
5039 BT_ERR("Frame is too long (len %d, expected len %d)",
5040 skb->len, len);
5041 l2cap_conn_unreliable(conn, ECOMM);
5042 goto drop;
5043 }
5044
5045 /* Allocate skb for the complete frame (with header) */
5046 conn->rx_skb = bt_skb_alloc(len, GFP_ATOMIC);
5047 if (!conn->rx_skb)
5048 goto drop;
5049
5050 skb_copy_from_linear_data(skb, skb_put(conn->rx_skb, skb->len),
5051 skb->len);
5052 conn->rx_len = len - skb->len;
5053 } else {
5054 BT_DBG("Cont: frag len %d (expecting %d)", skb->len, conn->rx_len);
5055
5056 if (!conn->rx_len) {
5057 BT_ERR("Unexpected continuation frame (len %d)", skb->len);
5058 l2cap_conn_unreliable(conn, ECOMM);
5059 goto drop;
5060 }
5061
5062 if (skb->len > conn->rx_len) {
5063 BT_ERR("Fragment is too long (len %d, expected %d)",
5064 skb->len, conn->rx_len);
5065 kfree_skb(conn->rx_skb);
5066 conn->rx_skb = NULL;
5067 conn->rx_len = 0;
5068 l2cap_conn_unreliable(conn, ECOMM);
5069 goto drop;
5070 }
5071
5072 skb_copy_from_linear_data(skb, skb_put(conn->rx_skb, skb->len),
5073 skb->len);
5074 conn->rx_len -= skb->len;
5075
5076 if (!conn->rx_len) {
5077 /* Complete frame received */
5078 l2cap_recv_frame(conn, conn->rx_skb);
5079 conn->rx_skb = NULL;
5080 }
5081 }
5082
5083drop:
5084 kfree_skb(skb);
5085 return 0;
5086}
5087
5088static int l2cap_debugfs_show(struct seq_file *f, void *p)
5089{
5090 struct l2cap_chan *c;
5091
5092 read_lock(&chan_list_lock);
5093
5094 list_for_each_entry(c, &chan_list, global_l) {
5095 struct sock *sk = c->sk;
5096
5097 seq_printf(f, "%s %s %d %d 0x%4.4x 0x%4.4x %d %d %d %d\n",
5098 batostr(&bt_sk(sk)->src),
5099 batostr(&bt_sk(sk)->dst),
5100 c->state, __le16_to_cpu(c->psm),
5101 c->scid, c->dcid, c->imtu, c->omtu,
5102 c->sec_level, c->mode);
5103 }
5104
5105 read_unlock(&chan_list_lock);
5106
5107 return 0;
5108}
5109
5110static int l2cap_debugfs_open(struct inode *inode, struct file *file)
5111{
5112 return single_open(file, l2cap_debugfs_show, inode->i_private);
5113}
5114
5115static const struct file_operations l2cap_debugfs_fops = {
5116 .open = l2cap_debugfs_open,
5117 .read = seq_read,
5118 .llseek = seq_lseek,
5119 .release = single_release,
5120};
5121
5122static struct dentry *l2cap_debugfs;
5123
5124int __init l2cap_init(void)
5125{
5126 int err;
5127
5128 err = l2cap_init_sockets();
5129 if (err < 0)
5130 return err;
5131
5132 if (bt_debugfs) {
5133 l2cap_debugfs = debugfs_create_file("l2cap", 0444,
5134 bt_debugfs, NULL, &l2cap_debugfs_fops);
5135 if (!l2cap_debugfs)
5136 BT_ERR("Failed to create L2CAP debug file");
5137 }
5138
5139 return 0;
5140}
5141
5142void l2cap_exit(void)
5143{
5144 debugfs_remove(l2cap_debugfs);
5145 l2cap_cleanup_sockets();
5146}
5147
5148module_param(disable_ertm, bool, 0644);
5149MODULE_PARM_DESC(disable_ertm, "Disable enhanced retransmission mode");