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v4.6
   1/*
   2   BlueZ - Bluetooth protocol stack for Linux
   3   Copyright (C) 2000-2001 Qualcomm Incorporated
   4   Copyright (C) 2009-2010 Gustavo F. Padovan <gustavo@padovan.org>
   5   Copyright (C) 2010 Google Inc.
   6   Copyright (C) 2011 ProFUSION Embedded Systems
   7   Copyright (c) 2012 Code Aurora Forum.  All rights reserved.
   8
   9   Written 2000,2001 by Maxim Krasnyansky <maxk@qualcomm.com>
  10
  11   This program is free software; you can redistribute it and/or modify
  12   it under the terms of the GNU General Public License version 2 as
  13   published by the Free Software Foundation;
  14
  15   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  16   OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17   FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS.
  18   IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) AND AUTHOR(S) BE LIABLE FOR ANY
  19   CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES
  20   WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  21   ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  22   OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  23
  24   ALL LIABILITY, INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PATENTS,
  25   COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS, RELATING TO USE OF THIS
  26   SOFTWARE IS DISCLAIMED.
  27*/
  28
  29/* Bluetooth L2CAP core. */
  30
  31#include <linux/module.h>
  32
  33#include <linux/debugfs.h>
  34#include <linux/crc16.h>
 
  35
  36#include <net/bluetooth/bluetooth.h>
  37#include <net/bluetooth/hci_core.h>
  38#include <net/bluetooth/l2cap.h>
  39
  40#include "smp.h"
  41#include "a2mp.h"
  42#include "amp.h"
  43
  44#define LE_FLOWCTL_MAX_CREDITS 65535
  45
  46bool disable_ertm;
 
  47
  48static u32 l2cap_feat_mask = L2CAP_FEAT_FIXED_CHAN | L2CAP_FEAT_UCD;
  49
  50static LIST_HEAD(chan_list);
  51static DEFINE_RWLOCK(chan_list_lock);
  52
  53static u16 le_max_credits = L2CAP_LE_MAX_CREDITS;
  54static u16 le_default_mps = L2CAP_LE_DEFAULT_MPS;
  55
  56static struct sk_buff *l2cap_build_cmd(struct l2cap_conn *conn,
  57				       u8 code, u8 ident, u16 dlen, void *data);
  58static void l2cap_send_cmd(struct l2cap_conn *conn, u8 ident, u8 code, u16 len,
  59			   void *data);
  60static int l2cap_build_conf_req(struct l2cap_chan *chan, void *data);
  61static void l2cap_send_disconn_req(struct l2cap_chan *chan, int err);
  62
  63static void l2cap_tx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
  64		     struct sk_buff_head *skbs, u8 event);
  65
  66static inline u8 bdaddr_type(u8 link_type, u8 bdaddr_type)
  67{
  68	if (link_type == LE_LINK) {
  69		if (bdaddr_type == ADDR_LE_DEV_PUBLIC)
  70			return BDADDR_LE_PUBLIC;
  71		else
  72			return BDADDR_LE_RANDOM;
  73	}
  74
  75	return BDADDR_BREDR;
  76}
  77
  78static inline u8 bdaddr_src_type(struct hci_conn *hcon)
  79{
  80	return bdaddr_type(hcon->type, hcon->src_type);
  81}
  82
  83static inline u8 bdaddr_dst_type(struct hci_conn *hcon)
  84{
  85	return bdaddr_type(hcon->type, hcon->dst_type);
  86}
  87
  88/* ---- L2CAP channels ---- */
  89
  90static struct l2cap_chan *__l2cap_get_chan_by_dcid(struct l2cap_conn *conn,
  91						   u16 cid)
  92{
  93	struct l2cap_chan *c;
  94
  95	list_for_each_entry(c, &conn->chan_l, list) {
  96		if (c->dcid == cid)
  97			return c;
  98	}
  99	return NULL;
 100}
 101
 102static struct l2cap_chan *__l2cap_get_chan_by_scid(struct l2cap_conn *conn,
 103						   u16 cid)
 104{
 105	struct l2cap_chan *c;
 106
 107	list_for_each_entry(c, &conn->chan_l, list) {
 108		if (c->scid == cid)
 109			return c;
 110	}
 111	return NULL;
 112}
 113
 114/* Find channel with given SCID.
 115 * Returns locked channel. */
 116static struct l2cap_chan *l2cap_get_chan_by_scid(struct l2cap_conn *conn,
 117						 u16 cid)
 118{
 119	struct l2cap_chan *c;
 120
 121	mutex_lock(&conn->chan_lock);
 122	c = __l2cap_get_chan_by_scid(conn, cid);
 123	if (c)
 124		l2cap_chan_lock(c);
 125	mutex_unlock(&conn->chan_lock);
 126
 127	return c;
 128}
 129
 130/* Find channel with given DCID.
 131 * Returns locked channel.
 132 */
 133static struct l2cap_chan *l2cap_get_chan_by_dcid(struct l2cap_conn *conn,
 134						 u16 cid)
 135{
 136	struct l2cap_chan *c;
 137
 138	mutex_lock(&conn->chan_lock);
 139	c = __l2cap_get_chan_by_dcid(conn, cid);
 140	if (c)
 141		l2cap_chan_lock(c);
 142	mutex_unlock(&conn->chan_lock);
 143
 144	return c;
 145}
 146
 147static struct l2cap_chan *__l2cap_get_chan_by_ident(struct l2cap_conn *conn,
 148						    u8 ident)
 149{
 150	struct l2cap_chan *c;
 151
 152	list_for_each_entry(c, &conn->chan_l, list) {
 153		if (c->ident == ident)
 154			return c;
 155	}
 156	return NULL;
 157}
 158
 159static struct l2cap_chan *l2cap_get_chan_by_ident(struct l2cap_conn *conn,
 160						  u8 ident)
 161{
 162	struct l2cap_chan *c;
 163
 164	mutex_lock(&conn->chan_lock);
 165	c = __l2cap_get_chan_by_ident(conn, ident);
 166	if (c)
 167		l2cap_chan_lock(c);
 168	mutex_unlock(&conn->chan_lock);
 169
 170	return c;
 171}
 172
 173static struct l2cap_chan *__l2cap_global_chan_by_addr(__le16 psm, bdaddr_t *src)
 
 174{
 175	struct l2cap_chan *c;
 176
 177	list_for_each_entry(c, &chan_list, global_l) {
 
 
 
 
 
 
 178		if (c->sport == psm && !bacmp(&c->src, src))
 179			return c;
 180	}
 181	return NULL;
 182}
 183
 184int l2cap_add_psm(struct l2cap_chan *chan, bdaddr_t *src, __le16 psm)
 185{
 186	int err;
 187
 188	write_lock(&chan_list_lock);
 189
 190	if (psm && __l2cap_global_chan_by_addr(psm, src)) {
 191		err = -EADDRINUSE;
 192		goto done;
 193	}
 194
 195	if (psm) {
 196		chan->psm = psm;
 197		chan->sport = psm;
 198		err = 0;
 199	} else {
 200		u16 p, start, end, incr;
 201
 202		if (chan->src_type == BDADDR_BREDR) {
 203			start = L2CAP_PSM_DYN_START;
 204			end = L2CAP_PSM_AUTO_END;
 205			incr = 2;
 206		} else {
 207			start = L2CAP_PSM_LE_DYN_START;
 208			end = L2CAP_PSM_LE_DYN_END;
 209			incr = 1;
 210		}
 211
 212		err = -EINVAL;
 213		for (p = start; p <= end; p += incr)
 214			if (!__l2cap_global_chan_by_addr(cpu_to_le16(p), src)) {
 
 215				chan->psm   = cpu_to_le16(p);
 216				chan->sport = cpu_to_le16(p);
 217				err = 0;
 218				break;
 219			}
 220	}
 221
 222done:
 223	write_unlock(&chan_list_lock);
 224	return err;
 225}
 226EXPORT_SYMBOL_GPL(l2cap_add_psm);
 227
 228int l2cap_add_scid(struct l2cap_chan *chan,  __u16 scid)
 229{
 230	write_lock(&chan_list_lock);
 231
 232	/* Override the defaults (which are for conn-oriented) */
 233	chan->omtu = L2CAP_DEFAULT_MTU;
 234	chan->chan_type = L2CAP_CHAN_FIXED;
 235
 236	chan->scid = scid;
 237
 238	write_unlock(&chan_list_lock);
 239
 240	return 0;
 241}
 242
 243static u16 l2cap_alloc_cid(struct l2cap_conn *conn)
 244{
 245	u16 cid, dyn_end;
 246
 247	if (conn->hcon->type == LE_LINK)
 248		dyn_end = L2CAP_CID_LE_DYN_END;
 249	else
 250		dyn_end = L2CAP_CID_DYN_END;
 251
 252	for (cid = L2CAP_CID_DYN_START; cid <= dyn_end; cid++) {
 253		if (!__l2cap_get_chan_by_scid(conn, cid))
 254			return cid;
 255	}
 256
 257	return 0;
 258}
 259
 260static void l2cap_state_change(struct l2cap_chan *chan, int state)
 261{
 262	BT_DBG("chan %p %s -> %s", chan, state_to_string(chan->state),
 263	       state_to_string(state));
 264
 265	chan->state = state;
 266	chan->ops->state_change(chan, state, 0);
 267}
 268
 269static inline void l2cap_state_change_and_error(struct l2cap_chan *chan,
 270						int state, int err)
 271{
 272	chan->state = state;
 273	chan->ops->state_change(chan, chan->state, err);
 274}
 275
 276static inline void l2cap_chan_set_err(struct l2cap_chan *chan, int err)
 277{
 278	chan->ops->state_change(chan, chan->state, err);
 279}
 280
 281static void __set_retrans_timer(struct l2cap_chan *chan)
 282{
 283	if (!delayed_work_pending(&chan->monitor_timer) &&
 284	    chan->retrans_timeout) {
 285		l2cap_set_timer(chan, &chan->retrans_timer,
 286				msecs_to_jiffies(chan->retrans_timeout));
 287	}
 288}
 289
 290static void __set_monitor_timer(struct l2cap_chan *chan)
 291{
 292	__clear_retrans_timer(chan);
 293	if (chan->monitor_timeout) {
 294		l2cap_set_timer(chan, &chan->monitor_timer,
 295				msecs_to_jiffies(chan->monitor_timeout));
 296	}
 297}
 298
 299static struct sk_buff *l2cap_ertm_seq_in_queue(struct sk_buff_head *head,
 300					       u16 seq)
 301{
 302	struct sk_buff *skb;
 303
 304	skb_queue_walk(head, skb) {
 305		if (bt_cb(skb)->l2cap.txseq == seq)
 306			return skb;
 307	}
 308
 309	return NULL;
 310}
 311
 312/* ---- L2CAP sequence number lists ---- */
 313
 314/* For ERTM, ordered lists of sequence numbers must be tracked for
 315 * SREJ requests that are received and for frames that are to be
 316 * retransmitted. These seq_list functions implement a singly-linked
 317 * list in an array, where membership in the list can also be checked
 318 * in constant time. Items can also be added to the tail of the list
 319 * and removed from the head in constant time, without further memory
 320 * allocs or frees.
 321 */
 322
 323static int l2cap_seq_list_init(struct l2cap_seq_list *seq_list, u16 size)
 324{
 325	size_t alloc_size, i;
 326
 327	/* Allocated size is a power of 2 to map sequence numbers
 328	 * (which may be up to 14 bits) in to a smaller array that is
 329	 * sized for the negotiated ERTM transmit windows.
 330	 */
 331	alloc_size = roundup_pow_of_two(size);
 332
 333	seq_list->list = kmalloc(sizeof(u16) * alloc_size, GFP_KERNEL);
 334	if (!seq_list->list)
 335		return -ENOMEM;
 336
 337	seq_list->mask = alloc_size - 1;
 338	seq_list->head = L2CAP_SEQ_LIST_CLEAR;
 339	seq_list->tail = L2CAP_SEQ_LIST_CLEAR;
 340	for (i = 0; i < alloc_size; i++)
 341		seq_list->list[i] = L2CAP_SEQ_LIST_CLEAR;
 342
 343	return 0;
 344}
 345
 346static inline void l2cap_seq_list_free(struct l2cap_seq_list *seq_list)
 347{
 348	kfree(seq_list->list);
 349}
 350
 351static inline bool l2cap_seq_list_contains(struct l2cap_seq_list *seq_list,
 352					   u16 seq)
 353{
 354	/* Constant-time check for list membership */
 355	return seq_list->list[seq & seq_list->mask] != L2CAP_SEQ_LIST_CLEAR;
 356}
 357
 358static inline u16 l2cap_seq_list_pop(struct l2cap_seq_list *seq_list)
 359{
 360	u16 seq = seq_list->head;
 361	u16 mask = seq_list->mask;
 362
 363	seq_list->head = seq_list->list[seq & mask];
 364	seq_list->list[seq & mask] = L2CAP_SEQ_LIST_CLEAR;
 365
 366	if (seq_list->head == L2CAP_SEQ_LIST_TAIL) {
 367		seq_list->head = L2CAP_SEQ_LIST_CLEAR;
 368		seq_list->tail = L2CAP_SEQ_LIST_CLEAR;
 369	}
 370
 371	return seq;
 372}
 373
 374static void l2cap_seq_list_clear(struct l2cap_seq_list *seq_list)
 375{
 376	u16 i;
 377
 378	if (seq_list->head == L2CAP_SEQ_LIST_CLEAR)
 379		return;
 380
 381	for (i = 0; i <= seq_list->mask; i++)
 382		seq_list->list[i] = L2CAP_SEQ_LIST_CLEAR;
 383
 384	seq_list->head = L2CAP_SEQ_LIST_CLEAR;
 385	seq_list->tail = L2CAP_SEQ_LIST_CLEAR;
 386}
 387
 388static void l2cap_seq_list_append(struct l2cap_seq_list *seq_list, u16 seq)
 389{
 390	u16 mask = seq_list->mask;
 391
 392	/* All appends happen in constant time */
 393
 394	if (seq_list->list[seq & mask] != L2CAP_SEQ_LIST_CLEAR)
 395		return;
 396
 397	if (seq_list->tail == L2CAP_SEQ_LIST_CLEAR)
 398		seq_list->head = seq;
 399	else
 400		seq_list->list[seq_list->tail & mask] = seq;
 401
 402	seq_list->tail = seq;
 403	seq_list->list[seq & mask] = L2CAP_SEQ_LIST_TAIL;
 404}
 405
 406static void l2cap_chan_timeout(struct work_struct *work)
 407{
 408	struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
 409					       chan_timer.work);
 410	struct l2cap_conn *conn = chan->conn;
 411	int reason;
 412
 413	BT_DBG("chan %p state %s", chan, state_to_string(chan->state));
 414
 415	mutex_lock(&conn->chan_lock);
 
 
 
 416	l2cap_chan_lock(chan);
 417
 418	if (chan->state == BT_CONNECTED || chan->state == BT_CONFIG)
 419		reason = ECONNREFUSED;
 420	else if (chan->state == BT_CONNECT &&
 421		 chan->sec_level != BT_SECURITY_SDP)
 422		reason = ECONNREFUSED;
 423	else
 424		reason = ETIMEDOUT;
 425
 426	l2cap_chan_close(chan, reason);
 427
 428	l2cap_chan_unlock(chan);
 429
 430	chan->ops->close(chan);
 431	mutex_unlock(&conn->chan_lock);
 432
 
 433	l2cap_chan_put(chan);
 
 
 434}
 435
 436struct l2cap_chan *l2cap_chan_create(void)
 437{
 438	struct l2cap_chan *chan;
 439
 440	chan = kzalloc(sizeof(*chan), GFP_ATOMIC);
 441	if (!chan)
 442		return NULL;
 443
 
 
 444	mutex_init(&chan->lock);
 445
 446	/* Set default lock nesting level */
 447	atomic_set(&chan->nesting, L2CAP_NESTING_NORMAL);
 448
 449	write_lock(&chan_list_lock);
 450	list_add(&chan->global_l, &chan_list);
 451	write_unlock(&chan_list_lock);
 452
 453	INIT_DELAYED_WORK(&chan->chan_timer, l2cap_chan_timeout);
 454
 455	chan->state = BT_OPEN;
 456
 457	kref_init(&chan->kref);
 458
 459	/* This flag is cleared in l2cap_chan_ready() */
 460	set_bit(CONF_NOT_COMPLETE, &chan->conf_state);
 461
 462	BT_DBG("chan %p", chan);
 463
 464	return chan;
 465}
 466EXPORT_SYMBOL_GPL(l2cap_chan_create);
 467
 468static void l2cap_chan_destroy(struct kref *kref)
 469{
 470	struct l2cap_chan *chan = container_of(kref, struct l2cap_chan, kref);
 471
 472	BT_DBG("chan %p", chan);
 473
 474	write_lock(&chan_list_lock);
 475	list_del(&chan->global_l);
 476	write_unlock(&chan_list_lock);
 477
 478	kfree(chan);
 479}
 480
 481void l2cap_chan_hold(struct l2cap_chan *c)
 482{
 483	BT_DBG("chan %p orig refcnt %d", c, atomic_read(&c->kref.refcount));
 484
 485	kref_get(&c->kref);
 486}
 487
 488void l2cap_chan_put(struct l2cap_chan *c)
 489{
 490	BT_DBG("chan %p orig refcnt %d", c, atomic_read(&c->kref.refcount));
 491
 492	kref_put(&c->kref, l2cap_chan_destroy);
 493}
 494EXPORT_SYMBOL_GPL(l2cap_chan_put);
 495
 496void l2cap_chan_set_defaults(struct l2cap_chan *chan)
 497{
 498	chan->fcs  = L2CAP_FCS_CRC16;
 499	chan->max_tx = L2CAP_DEFAULT_MAX_TX;
 500	chan->tx_win = L2CAP_DEFAULT_TX_WINDOW;
 501	chan->tx_win_max = L2CAP_DEFAULT_TX_WINDOW;
 502	chan->remote_max_tx = chan->max_tx;
 503	chan->remote_tx_win = chan->tx_win;
 504	chan->ack_win = L2CAP_DEFAULT_TX_WINDOW;
 505	chan->sec_level = BT_SECURITY_LOW;
 506	chan->flush_to = L2CAP_DEFAULT_FLUSH_TO;
 507	chan->retrans_timeout = L2CAP_DEFAULT_RETRANS_TO;
 508	chan->monitor_timeout = L2CAP_DEFAULT_MONITOR_TO;
 
 509	chan->conf_state = 0;
 
 510
 511	set_bit(FLAG_FORCE_ACTIVE, &chan->flags);
 512}
 513EXPORT_SYMBOL_GPL(l2cap_chan_set_defaults);
 514
 515static void l2cap_le_flowctl_init(struct l2cap_chan *chan)
 516{
 517	chan->sdu = NULL;
 518	chan->sdu_last_frag = NULL;
 519	chan->sdu_len = 0;
 520	chan->tx_credits = 0;
 521	chan->rx_credits = le_max_credits;
 522	chan->mps = min_t(u16, chan->imtu, le_default_mps);
 
 
 523
 524	skb_queue_head_init(&chan->tx_q);
 525}
 526
 
 
 
 
 
 
 
 
 
 
 
 527void __l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan)
 528{
 529	BT_DBG("conn %p, psm 0x%2.2x, dcid 0x%4.4x", conn,
 530	       __le16_to_cpu(chan->psm), chan->dcid);
 531
 532	conn->disc_reason = HCI_ERROR_REMOTE_USER_TERM;
 533
 534	chan->conn = conn;
 535
 536	switch (chan->chan_type) {
 537	case L2CAP_CHAN_CONN_ORIENTED:
 538		/* Alloc CID for connection-oriented socket */
 539		chan->scid = l2cap_alloc_cid(conn);
 540		if (conn->hcon->type == ACL_LINK)
 541			chan->omtu = L2CAP_DEFAULT_MTU;
 542		break;
 543
 544	case L2CAP_CHAN_CONN_LESS:
 545		/* Connectionless socket */
 546		chan->scid = L2CAP_CID_CONN_LESS;
 547		chan->dcid = L2CAP_CID_CONN_LESS;
 548		chan->omtu = L2CAP_DEFAULT_MTU;
 549		break;
 550
 551	case L2CAP_CHAN_FIXED:
 552		/* Caller will set CID and CID specific MTU values */
 553		break;
 554
 555	default:
 556		/* Raw socket can send/recv signalling messages only */
 557		chan->scid = L2CAP_CID_SIGNALING;
 558		chan->dcid = L2CAP_CID_SIGNALING;
 559		chan->omtu = L2CAP_DEFAULT_MTU;
 560	}
 561
 562	chan->local_id		= L2CAP_BESTEFFORT_ID;
 563	chan->local_stype	= L2CAP_SERV_BESTEFFORT;
 564	chan->local_msdu	= L2CAP_DEFAULT_MAX_SDU_SIZE;
 565	chan->local_sdu_itime	= L2CAP_DEFAULT_SDU_ITIME;
 566	chan->local_acc_lat	= L2CAP_DEFAULT_ACC_LAT;
 567	chan->local_flush_to	= L2CAP_EFS_DEFAULT_FLUSH_TO;
 568
 569	l2cap_chan_hold(chan);
 570
 571	/* Only keep a reference for fixed channels if they requested it */
 572	if (chan->chan_type != L2CAP_CHAN_FIXED ||
 573	    test_bit(FLAG_HOLD_HCI_CONN, &chan->flags))
 574		hci_conn_hold(conn->hcon);
 575
 576	list_add(&chan->list, &conn->chan_l);
 577}
 578
 579void l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan)
 580{
 581	mutex_lock(&conn->chan_lock);
 582	__l2cap_chan_add(conn, chan);
 583	mutex_unlock(&conn->chan_lock);
 584}
 585
 586void l2cap_chan_del(struct l2cap_chan *chan, int err)
 587{
 588	struct l2cap_conn *conn = chan->conn;
 589
 590	__clear_chan_timer(chan);
 591
 592	BT_DBG("chan %p, conn %p, err %d, state %s", chan, conn, err,
 593	       state_to_string(chan->state));
 594
 595	chan->ops->teardown(chan, err);
 596
 597	if (conn) {
 598		struct amp_mgr *mgr = conn->hcon->amp_mgr;
 599		/* Delete from channel list */
 600		list_del(&chan->list);
 601
 602		l2cap_chan_put(chan);
 603
 604		chan->conn = NULL;
 605
 606		/* Reference was only held for non-fixed channels or
 607		 * fixed channels that explicitly requested it using the
 608		 * FLAG_HOLD_HCI_CONN flag.
 609		 */
 610		if (chan->chan_type != L2CAP_CHAN_FIXED ||
 611		    test_bit(FLAG_HOLD_HCI_CONN, &chan->flags))
 612			hci_conn_drop(conn->hcon);
 613
 614		if (mgr && mgr->bredr_chan == chan)
 615			mgr->bredr_chan = NULL;
 616	}
 617
 618	if (chan->hs_hchan) {
 619		struct hci_chan *hs_hchan = chan->hs_hchan;
 620
 621		BT_DBG("chan %p disconnect hs_hchan %p", chan, hs_hchan);
 622		amp_disconnect_logical_link(hs_hchan);
 623	}
 624
 625	if (test_bit(CONF_NOT_COMPLETE, &chan->conf_state))
 626		return;
 627
 628	switch(chan->mode) {
 629	case L2CAP_MODE_BASIC:
 630		break;
 631
 632	case L2CAP_MODE_LE_FLOWCTL:
 
 633		skb_queue_purge(&chan->tx_q);
 634		break;
 635
 636	case L2CAP_MODE_ERTM:
 637		__clear_retrans_timer(chan);
 638		__clear_monitor_timer(chan);
 639		__clear_ack_timer(chan);
 640
 641		skb_queue_purge(&chan->srej_q);
 642
 643		l2cap_seq_list_free(&chan->srej_list);
 644		l2cap_seq_list_free(&chan->retrans_list);
 645
 646		/* fall through */
 647
 648	case L2CAP_MODE_STREAMING:
 649		skb_queue_purge(&chan->tx_q);
 650		break;
 651	}
 652
 653	return;
 654}
 655EXPORT_SYMBOL_GPL(l2cap_chan_del);
 656
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 657static void l2cap_conn_update_id_addr(struct work_struct *work)
 658{
 659	struct l2cap_conn *conn = container_of(work, struct l2cap_conn,
 660					       id_addr_update_work);
 661	struct hci_conn *hcon = conn->hcon;
 662	struct l2cap_chan *chan;
 663
 664	mutex_lock(&conn->chan_lock);
 665
 666	list_for_each_entry(chan, &conn->chan_l, list) {
 667		l2cap_chan_lock(chan);
 668		bacpy(&chan->dst, &hcon->dst);
 669		chan->dst_type = bdaddr_dst_type(hcon);
 670		l2cap_chan_unlock(chan);
 671	}
 672
 673	mutex_unlock(&conn->chan_lock);
 674}
 675
 676static void l2cap_chan_le_connect_reject(struct l2cap_chan *chan)
 677{
 678	struct l2cap_conn *conn = chan->conn;
 679	struct l2cap_le_conn_rsp rsp;
 680	u16 result;
 681
 682	if (test_bit(FLAG_DEFER_SETUP, &chan->flags))
 683		result = L2CAP_CR_AUTHORIZATION;
 684	else
 685		result = L2CAP_CR_BAD_PSM;
 686
 687	l2cap_state_change(chan, BT_DISCONN);
 688
 689	rsp.dcid    = cpu_to_le16(chan->scid);
 690	rsp.mtu     = cpu_to_le16(chan->imtu);
 691	rsp.mps     = cpu_to_le16(chan->mps);
 692	rsp.credits = cpu_to_le16(chan->rx_credits);
 693	rsp.result  = cpu_to_le16(result);
 694
 695	l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CONN_RSP, sizeof(rsp),
 696		       &rsp);
 697}
 698
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 699static void l2cap_chan_connect_reject(struct l2cap_chan *chan)
 700{
 701	struct l2cap_conn *conn = chan->conn;
 702	struct l2cap_conn_rsp rsp;
 703	u16 result;
 704
 705	if (test_bit(FLAG_DEFER_SETUP, &chan->flags))
 706		result = L2CAP_CR_SEC_BLOCK;
 707	else
 708		result = L2CAP_CR_BAD_PSM;
 709
 710	l2cap_state_change(chan, BT_DISCONN);
 711
 712	rsp.scid   = cpu_to_le16(chan->dcid);
 713	rsp.dcid   = cpu_to_le16(chan->scid);
 714	rsp.result = cpu_to_le16(result);
 715	rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
 716
 717	l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP, sizeof(rsp), &rsp);
 718}
 719
 720void l2cap_chan_close(struct l2cap_chan *chan, int reason)
 721{
 722	struct l2cap_conn *conn = chan->conn;
 723
 724	BT_DBG("chan %p state %s", chan, state_to_string(chan->state));
 725
 726	switch (chan->state) {
 727	case BT_LISTEN:
 728		chan->ops->teardown(chan, 0);
 729		break;
 730
 731	case BT_CONNECTED:
 732	case BT_CONFIG:
 733		if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED) {
 734			__set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
 735			l2cap_send_disconn_req(chan, reason);
 736		} else
 737			l2cap_chan_del(chan, reason);
 738		break;
 739
 740	case BT_CONNECT2:
 741		if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED) {
 742			if (conn->hcon->type == ACL_LINK)
 743				l2cap_chan_connect_reject(chan);
 744			else if (conn->hcon->type == LE_LINK)
 745				l2cap_chan_le_connect_reject(chan);
 
 
 
 
 
 
 
 
 746		}
 747
 748		l2cap_chan_del(chan, reason);
 749		break;
 750
 751	case BT_CONNECT:
 752	case BT_DISCONN:
 753		l2cap_chan_del(chan, reason);
 754		break;
 755
 756	default:
 757		chan->ops->teardown(chan, 0);
 758		break;
 759	}
 760}
 761EXPORT_SYMBOL(l2cap_chan_close);
 762
 763static inline u8 l2cap_get_auth_type(struct l2cap_chan *chan)
 764{
 765	switch (chan->chan_type) {
 766	case L2CAP_CHAN_RAW:
 767		switch (chan->sec_level) {
 768		case BT_SECURITY_HIGH:
 769		case BT_SECURITY_FIPS:
 770			return HCI_AT_DEDICATED_BONDING_MITM;
 771		case BT_SECURITY_MEDIUM:
 772			return HCI_AT_DEDICATED_BONDING;
 773		default:
 774			return HCI_AT_NO_BONDING;
 775		}
 776		break;
 777	case L2CAP_CHAN_CONN_LESS:
 778		if (chan->psm == cpu_to_le16(L2CAP_PSM_3DSP)) {
 779			if (chan->sec_level == BT_SECURITY_LOW)
 780				chan->sec_level = BT_SECURITY_SDP;
 781		}
 782		if (chan->sec_level == BT_SECURITY_HIGH ||
 783		    chan->sec_level == BT_SECURITY_FIPS)
 784			return HCI_AT_NO_BONDING_MITM;
 785		else
 786			return HCI_AT_NO_BONDING;
 787		break;
 788	case L2CAP_CHAN_CONN_ORIENTED:
 789		if (chan->psm == cpu_to_le16(L2CAP_PSM_SDP)) {
 790			if (chan->sec_level == BT_SECURITY_LOW)
 791				chan->sec_level = BT_SECURITY_SDP;
 792
 793			if (chan->sec_level == BT_SECURITY_HIGH ||
 794			    chan->sec_level == BT_SECURITY_FIPS)
 795				return HCI_AT_NO_BONDING_MITM;
 796			else
 797				return HCI_AT_NO_BONDING;
 798		}
 799		/* fall through */
 
 800	default:
 801		switch (chan->sec_level) {
 802		case BT_SECURITY_HIGH:
 803		case BT_SECURITY_FIPS:
 804			return HCI_AT_GENERAL_BONDING_MITM;
 805		case BT_SECURITY_MEDIUM:
 806			return HCI_AT_GENERAL_BONDING;
 807		default:
 808			return HCI_AT_NO_BONDING;
 809		}
 810		break;
 811	}
 812}
 813
 814/* Service level security */
 815int l2cap_chan_check_security(struct l2cap_chan *chan, bool initiator)
 816{
 817	struct l2cap_conn *conn = chan->conn;
 818	__u8 auth_type;
 819
 820	if (conn->hcon->type == LE_LINK)
 821		return smp_conn_security(conn->hcon, chan->sec_level);
 822
 823	auth_type = l2cap_get_auth_type(chan);
 824
 825	return hci_conn_security(conn->hcon, chan->sec_level, auth_type,
 826				 initiator);
 827}
 828
 829static u8 l2cap_get_ident(struct l2cap_conn *conn)
 830{
 831	u8 id;
 832
 833	/* Get next available identificator.
 834	 *    1 - 128 are used by kernel.
 835	 *  129 - 199 are reserved.
 836	 *  200 - 254 are used by utilities like l2ping, etc.
 837	 */
 838
 839	mutex_lock(&conn->ident_lock);
 840
 841	if (++conn->tx_ident > 128)
 842		conn->tx_ident = 1;
 843
 844	id = conn->tx_ident;
 845
 846	mutex_unlock(&conn->ident_lock);
 847
 848	return id;
 849}
 850
 851static void l2cap_send_cmd(struct l2cap_conn *conn, u8 ident, u8 code, u16 len,
 852			   void *data)
 853{
 854	struct sk_buff *skb = l2cap_build_cmd(conn, code, ident, len, data);
 855	u8 flags;
 856
 857	BT_DBG("code 0x%2.2x", code);
 858
 859	if (!skb)
 860		return;
 861
 862	/* Use NO_FLUSH if supported or we have an LE link (which does
 863	 * not support auto-flushing packets) */
 864	if (lmp_no_flush_capable(conn->hcon->hdev) ||
 865	    conn->hcon->type == LE_LINK)
 866		flags = ACL_START_NO_FLUSH;
 867	else
 868		flags = ACL_START;
 869
 870	bt_cb(skb)->force_active = BT_POWER_FORCE_ACTIVE_ON;
 871	skb->priority = HCI_PRIO_MAX;
 872
 873	hci_send_acl(conn->hchan, skb, flags);
 874}
 875
 876static bool __chan_is_moving(struct l2cap_chan *chan)
 877{
 878	return chan->move_state != L2CAP_MOVE_STABLE &&
 879	       chan->move_state != L2CAP_MOVE_WAIT_PREPARE;
 880}
 881
 882static void l2cap_do_send(struct l2cap_chan *chan, struct sk_buff *skb)
 883{
 884	struct hci_conn *hcon = chan->conn->hcon;
 885	u16 flags;
 886
 887	BT_DBG("chan %p, skb %p len %d priority %u", chan, skb, skb->len,
 888	       skb->priority);
 889
 890	if (chan->hs_hcon && !__chan_is_moving(chan)) {
 891		if (chan->hs_hchan)
 892			hci_send_acl(chan->hs_hchan, skb, ACL_COMPLETE);
 893		else
 894			kfree_skb(skb);
 895
 896		return;
 897	}
 898
 899	/* Use NO_FLUSH for LE links (where this is the only option) or
 900	 * if the BR/EDR link supports it and flushing has not been
 901	 * explicitly requested (through FLAG_FLUSHABLE).
 902	 */
 903	if (hcon->type == LE_LINK ||
 904	    (!test_bit(FLAG_FLUSHABLE, &chan->flags) &&
 905	     lmp_no_flush_capable(hcon->hdev)))
 906		flags = ACL_START_NO_FLUSH;
 907	else
 908		flags = ACL_START;
 909
 910	bt_cb(skb)->force_active = test_bit(FLAG_FORCE_ACTIVE, &chan->flags);
 911	hci_send_acl(chan->conn->hchan, skb, flags);
 912}
 913
 914static void __unpack_enhanced_control(u16 enh, struct l2cap_ctrl *control)
 915{
 916	control->reqseq = (enh & L2CAP_CTRL_REQSEQ) >> L2CAP_CTRL_REQSEQ_SHIFT;
 917	control->final = (enh & L2CAP_CTRL_FINAL) >> L2CAP_CTRL_FINAL_SHIFT;
 918
 919	if (enh & L2CAP_CTRL_FRAME_TYPE) {
 920		/* S-Frame */
 921		control->sframe = 1;
 922		control->poll = (enh & L2CAP_CTRL_POLL) >> L2CAP_CTRL_POLL_SHIFT;
 923		control->super = (enh & L2CAP_CTRL_SUPERVISE) >> L2CAP_CTRL_SUPER_SHIFT;
 924
 925		control->sar = 0;
 926		control->txseq = 0;
 927	} else {
 928		/* I-Frame */
 929		control->sframe = 0;
 930		control->sar = (enh & L2CAP_CTRL_SAR) >> L2CAP_CTRL_SAR_SHIFT;
 931		control->txseq = (enh & L2CAP_CTRL_TXSEQ) >> L2CAP_CTRL_TXSEQ_SHIFT;
 932
 933		control->poll = 0;
 934		control->super = 0;
 935	}
 936}
 937
 938static void __unpack_extended_control(u32 ext, struct l2cap_ctrl *control)
 939{
 940	control->reqseq = (ext & L2CAP_EXT_CTRL_REQSEQ) >> L2CAP_EXT_CTRL_REQSEQ_SHIFT;
 941	control->final = (ext & L2CAP_EXT_CTRL_FINAL) >> L2CAP_EXT_CTRL_FINAL_SHIFT;
 942
 943	if (ext & L2CAP_EXT_CTRL_FRAME_TYPE) {
 944		/* S-Frame */
 945		control->sframe = 1;
 946		control->poll = (ext & L2CAP_EXT_CTRL_POLL) >> L2CAP_EXT_CTRL_POLL_SHIFT;
 947		control->super = (ext & L2CAP_EXT_CTRL_SUPERVISE) >> L2CAP_EXT_CTRL_SUPER_SHIFT;
 948
 949		control->sar = 0;
 950		control->txseq = 0;
 951	} else {
 952		/* I-Frame */
 953		control->sframe = 0;
 954		control->sar = (ext & L2CAP_EXT_CTRL_SAR) >> L2CAP_EXT_CTRL_SAR_SHIFT;
 955		control->txseq = (ext & L2CAP_EXT_CTRL_TXSEQ) >> L2CAP_EXT_CTRL_TXSEQ_SHIFT;
 956
 957		control->poll = 0;
 958		control->super = 0;
 959	}
 960}
 961
 962static inline void __unpack_control(struct l2cap_chan *chan,
 963				    struct sk_buff *skb)
 964{
 965	if (test_bit(FLAG_EXT_CTRL, &chan->flags)) {
 966		__unpack_extended_control(get_unaligned_le32(skb->data),
 967					  &bt_cb(skb)->l2cap);
 968		skb_pull(skb, L2CAP_EXT_CTRL_SIZE);
 969	} else {
 970		__unpack_enhanced_control(get_unaligned_le16(skb->data),
 971					  &bt_cb(skb)->l2cap);
 972		skb_pull(skb, L2CAP_ENH_CTRL_SIZE);
 973	}
 974}
 975
 976static u32 __pack_extended_control(struct l2cap_ctrl *control)
 977{
 978	u32 packed;
 979
 980	packed = control->reqseq << L2CAP_EXT_CTRL_REQSEQ_SHIFT;
 981	packed |= control->final << L2CAP_EXT_CTRL_FINAL_SHIFT;
 982
 983	if (control->sframe) {
 984		packed |= control->poll << L2CAP_EXT_CTRL_POLL_SHIFT;
 985		packed |= control->super << L2CAP_EXT_CTRL_SUPER_SHIFT;
 986		packed |= L2CAP_EXT_CTRL_FRAME_TYPE;
 987	} else {
 988		packed |= control->sar << L2CAP_EXT_CTRL_SAR_SHIFT;
 989		packed |= control->txseq << L2CAP_EXT_CTRL_TXSEQ_SHIFT;
 990	}
 991
 992	return packed;
 993}
 994
 995static u16 __pack_enhanced_control(struct l2cap_ctrl *control)
 996{
 997	u16 packed;
 998
 999	packed = control->reqseq << L2CAP_CTRL_REQSEQ_SHIFT;
1000	packed |= control->final << L2CAP_CTRL_FINAL_SHIFT;
1001
1002	if (control->sframe) {
1003		packed |= control->poll << L2CAP_CTRL_POLL_SHIFT;
1004		packed |= control->super << L2CAP_CTRL_SUPER_SHIFT;
1005		packed |= L2CAP_CTRL_FRAME_TYPE;
1006	} else {
1007		packed |= control->sar << L2CAP_CTRL_SAR_SHIFT;
1008		packed |= control->txseq << L2CAP_CTRL_TXSEQ_SHIFT;
1009	}
1010
1011	return packed;
1012}
1013
1014static inline void __pack_control(struct l2cap_chan *chan,
1015				  struct l2cap_ctrl *control,
1016				  struct sk_buff *skb)
1017{
1018	if (test_bit(FLAG_EXT_CTRL, &chan->flags)) {
1019		put_unaligned_le32(__pack_extended_control(control),
1020				   skb->data + L2CAP_HDR_SIZE);
1021	} else {
1022		put_unaligned_le16(__pack_enhanced_control(control),
1023				   skb->data + L2CAP_HDR_SIZE);
1024	}
1025}
1026
1027static inline unsigned int __ertm_hdr_size(struct l2cap_chan *chan)
1028{
1029	if (test_bit(FLAG_EXT_CTRL, &chan->flags))
1030		return L2CAP_EXT_HDR_SIZE;
1031	else
1032		return L2CAP_ENH_HDR_SIZE;
1033}
1034
1035static struct sk_buff *l2cap_create_sframe_pdu(struct l2cap_chan *chan,
1036					       u32 control)
1037{
1038	struct sk_buff *skb;
1039	struct l2cap_hdr *lh;
1040	int hlen = __ertm_hdr_size(chan);
1041
1042	if (chan->fcs == L2CAP_FCS_CRC16)
1043		hlen += L2CAP_FCS_SIZE;
1044
1045	skb = bt_skb_alloc(hlen, GFP_KERNEL);
1046
1047	if (!skb)
1048		return ERR_PTR(-ENOMEM);
1049
1050	lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
1051	lh->len = cpu_to_le16(hlen - L2CAP_HDR_SIZE);
1052	lh->cid = cpu_to_le16(chan->dcid);
1053
1054	if (test_bit(FLAG_EXT_CTRL, &chan->flags))
1055		put_unaligned_le32(control, skb_put(skb, L2CAP_EXT_CTRL_SIZE));
1056	else
1057		put_unaligned_le16(control, skb_put(skb, L2CAP_ENH_CTRL_SIZE));
1058
1059	if (chan->fcs == L2CAP_FCS_CRC16) {
1060		u16 fcs = crc16(0, (u8 *)skb->data, skb->len);
1061		put_unaligned_le16(fcs, skb_put(skb, L2CAP_FCS_SIZE));
1062	}
1063
1064	skb->priority = HCI_PRIO_MAX;
1065	return skb;
1066}
1067
1068static void l2cap_send_sframe(struct l2cap_chan *chan,
1069			      struct l2cap_ctrl *control)
1070{
1071	struct sk_buff *skb;
1072	u32 control_field;
1073
1074	BT_DBG("chan %p, control %p", chan, control);
1075
1076	if (!control->sframe)
1077		return;
1078
1079	if (__chan_is_moving(chan))
1080		return;
1081
1082	if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state) &&
1083	    !control->poll)
1084		control->final = 1;
1085
1086	if (control->super == L2CAP_SUPER_RR)
1087		clear_bit(CONN_RNR_SENT, &chan->conn_state);
1088	else if (control->super == L2CAP_SUPER_RNR)
1089		set_bit(CONN_RNR_SENT, &chan->conn_state);
1090
1091	if (control->super != L2CAP_SUPER_SREJ) {
1092		chan->last_acked_seq = control->reqseq;
1093		__clear_ack_timer(chan);
1094	}
1095
1096	BT_DBG("reqseq %d, final %d, poll %d, super %d", control->reqseq,
1097	       control->final, control->poll, control->super);
1098
1099	if (test_bit(FLAG_EXT_CTRL, &chan->flags))
1100		control_field = __pack_extended_control(control);
1101	else
1102		control_field = __pack_enhanced_control(control);
1103
1104	skb = l2cap_create_sframe_pdu(chan, control_field);
1105	if (!IS_ERR(skb))
1106		l2cap_do_send(chan, skb);
1107}
1108
1109static void l2cap_send_rr_or_rnr(struct l2cap_chan *chan, bool poll)
1110{
1111	struct l2cap_ctrl control;
1112
1113	BT_DBG("chan %p, poll %d", chan, poll);
1114
1115	memset(&control, 0, sizeof(control));
1116	control.sframe = 1;
1117	control.poll = poll;
1118
1119	if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state))
1120		control.super = L2CAP_SUPER_RNR;
1121	else
1122		control.super = L2CAP_SUPER_RR;
1123
1124	control.reqseq = chan->buffer_seq;
1125	l2cap_send_sframe(chan, &control);
1126}
1127
1128static inline int __l2cap_no_conn_pending(struct l2cap_chan *chan)
1129{
1130	if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED)
1131		return true;
1132
1133	return !test_bit(CONF_CONNECT_PEND, &chan->conf_state);
1134}
1135
1136static bool __amp_capable(struct l2cap_chan *chan)
1137{
1138	struct l2cap_conn *conn = chan->conn;
1139	struct hci_dev *hdev;
1140	bool amp_available = false;
1141
1142	if (!(conn->local_fixed_chan & L2CAP_FC_A2MP))
1143		return false;
1144
1145	if (!(conn->remote_fixed_chan & L2CAP_FC_A2MP))
1146		return false;
1147
1148	read_lock(&hci_dev_list_lock);
1149	list_for_each_entry(hdev, &hci_dev_list, list) {
1150		if (hdev->amp_type != AMP_TYPE_BREDR &&
1151		    test_bit(HCI_UP, &hdev->flags)) {
1152			amp_available = true;
1153			break;
1154		}
1155	}
1156	read_unlock(&hci_dev_list_lock);
1157
1158	if (chan->chan_policy == BT_CHANNEL_POLICY_AMP_PREFERRED)
1159		return amp_available;
1160
1161	return false;
1162}
1163
1164static bool l2cap_check_efs(struct l2cap_chan *chan)
1165{
1166	/* Check EFS parameters */
1167	return true;
1168}
1169
1170void l2cap_send_conn_req(struct l2cap_chan *chan)
1171{
1172	struct l2cap_conn *conn = chan->conn;
1173	struct l2cap_conn_req req;
1174
1175	req.scid = cpu_to_le16(chan->scid);
1176	req.psm  = chan->psm;
1177
1178	chan->ident = l2cap_get_ident(conn);
1179
1180	set_bit(CONF_CONNECT_PEND, &chan->conf_state);
1181
1182	l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_REQ, sizeof(req), &req);
1183}
1184
1185static void l2cap_send_create_chan_req(struct l2cap_chan *chan, u8 amp_id)
1186{
1187	struct l2cap_create_chan_req req;
1188	req.scid = cpu_to_le16(chan->scid);
1189	req.psm  = chan->psm;
1190	req.amp_id = amp_id;
1191
1192	chan->ident = l2cap_get_ident(chan->conn);
1193
1194	l2cap_send_cmd(chan->conn, chan->ident, L2CAP_CREATE_CHAN_REQ,
1195		       sizeof(req), &req);
1196}
1197
1198static void l2cap_move_setup(struct l2cap_chan *chan)
1199{
1200	struct sk_buff *skb;
1201
1202	BT_DBG("chan %p", chan);
1203
1204	if (chan->mode != L2CAP_MODE_ERTM)
1205		return;
1206
1207	__clear_retrans_timer(chan);
1208	__clear_monitor_timer(chan);
1209	__clear_ack_timer(chan);
1210
1211	chan->retry_count = 0;
1212	skb_queue_walk(&chan->tx_q, skb) {
1213		if (bt_cb(skb)->l2cap.retries)
1214			bt_cb(skb)->l2cap.retries = 1;
1215		else
1216			break;
1217	}
1218
1219	chan->expected_tx_seq = chan->buffer_seq;
1220
1221	clear_bit(CONN_REJ_ACT, &chan->conn_state);
1222	clear_bit(CONN_SREJ_ACT, &chan->conn_state);
1223	l2cap_seq_list_clear(&chan->retrans_list);
1224	l2cap_seq_list_clear(&chan->srej_list);
1225	skb_queue_purge(&chan->srej_q);
1226
1227	chan->tx_state = L2CAP_TX_STATE_XMIT;
1228	chan->rx_state = L2CAP_RX_STATE_MOVE;
1229
1230	set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
1231}
1232
1233static void l2cap_move_done(struct l2cap_chan *chan)
1234{
1235	u8 move_role = chan->move_role;
1236	BT_DBG("chan %p", chan);
1237
1238	chan->move_state = L2CAP_MOVE_STABLE;
1239	chan->move_role = L2CAP_MOVE_ROLE_NONE;
1240
1241	if (chan->mode != L2CAP_MODE_ERTM)
1242		return;
1243
1244	switch (move_role) {
1245	case L2CAP_MOVE_ROLE_INITIATOR:
1246		l2cap_tx(chan, NULL, NULL, L2CAP_EV_EXPLICIT_POLL);
1247		chan->rx_state = L2CAP_RX_STATE_WAIT_F;
1248		break;
1249	case L2CAP_MOVE_ROLE_RESPONDER:
1250		chan->rx_state = L2CAP_RX_STATE_WAIT_P;
1251		break;
1252	}
1253}
1254
1255static void l2cap_chan_ready(struct l2cap_chan *chan)
1256{
1257	/* The channel may have already been flagged as connected in
1258	 * case of receiving data before the L2CAP info req/rsp
1259	 * procedure is complete.
1260	 */
1261	if (chan->state == BT_CONNECTED)
1262		return;
1263
1264	/* This clears all conf flags, including CONF_NOT_COMPLETE */
1265	chan->conf_state = 0;
1266	__clear_chan_timer(chan);
1267
1268	if (chan->mode == L2CAP_MODE_LE_FLOWCTL && !chan->tx_credits)
1269		chan->ops->suspend(chan);
 
 
 
 
 
1270
1271	chan->state = BT_CONNECTED;
1272
1273	chan->ops->ready(chan);
1274}
1275
1276static void l2cap_le_connect(struct l2cap_chan *chan)
1277{
1278	struct l2cap_conn *conn = chan->conn;
1279	struct l2cap_le_conn_req req;
1280
1281	if (test_and_set_bit(FLAG_LE_CONN_REQ_SENT, &chan->flags))
1282		return;
1283
 
 
 
 
 
1284	req.psm     = chan->psm;
1285	req.scid    = cpu_to_le16(chan->scid);
1286	req.mtu     = cpu_to_le16(chan->imtu);
1287	req.mps     = cpu_to_le16(chan->mps);
1288	req.credits = cpu_to_le16(chan->rx_credits);
1289
1290	chan->ident = l2cap_get_ident(conn);
1291
1292	l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CONN_REQ,
1293		       sizeof(req), &req);
1294}
1295
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1296static void l2cap_le_start(struct l2cap_chan *chan)
1297{
1298	struct l2cap_conn *conn = chan->conn;
1299
1300	if (!smp_conn_security(conn->hcon, chan->sec_level))
1301		return;
1302
1303	if (!chan->psm) {
1304		l2cap_chan_ready(chan);
1305		return;
1306	}
1307
1308	if (chan->state == BT_CONNECT)
1309		l2cap_le_connect(chan);
 
 
 
 
1310}
1311
1312static void l2cap_start_connection(struct l2cap_chan *chan)
1313{
1314	if (__amp_capable(chan)) {
1315		BT_DBG("chan %p AMP capable: discover AMPs", chan);
1316		a2mp_discover_amp(chan);
1317	} else if (chan->conn->hcon->type == LE_LINK) {
1318		l2cap_le_start(chan);
1319	} else {
1320		l2cap_send_conn_req(chan);
1321	}
1322}
1323
1324static void l2cap_request_info(struct l2cap_conn *conn)
1325{
1326	struct l2cap_info_req req;
1327
1328	if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT)
1329		return;
1330
1331	req.type = cpu_to_le16(L2CAP_IT_FEAT_MASK);
1332
1333	conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_SENT;
1334	conn->info_ident = l2cap_get_ident(conn);
1335
1336	schedule_delayed_work(&conn->info_timer, L2CAP_INFO_TIMEOUT);
1337
1338	l2cap_send_cmd(conn, conn->info_ident, L2CAP_INFO_REQ,
1339		       sizeof(req), &req);
1340}
1341
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1342static void l2cap_do_start(struct l2cap_chan *chan)
1343{
1344	struct l2cap_conn *conn = chan->conn;
1345
1346	if (conn->hcon->type == LE_LINK) {
1347		l2cap_le_start(chan);
1348		return;
1349	}
1350
1351	if (!(conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT)) {
1352		l2cap_request_info(conn);
1353		return;
1354	}
1355
1356	if (!(conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE))
1357		return;
1358
1359	if (l2cap_chan_check_security(chan, true) &&
1360	    __l2cap_no_conn_pending(chan))
 
 
 
1361		l2cap_start_connection(chan);
 
 
1362}
1363
1364static inline int l2cap_mode_supported(__u8 mode, __u32 feat_mask)
1365{
1366	u32 local_feat_mask = l2cap_feat_mask;
1367	if (!disable_ertm)
1368		local_feat_mask |= L2CAP_FEAT_ERTM | L2CAP_FEAT_STREAMING;
1369
1370	switch (mode) {
1371	case L2CAP_MODE_ERTM:
1372		return L2CAP_FEAT_ERTM & feat_mask & local_feat_mask;
1373	case L2CAP_MODE_STREAMING:
1374		return L2CAP_FEAT_STREAMING & feat_mask & local_feat_mask;
1375	default:
1376		return 0x00;
1377	}
1378}
1379
1380static void l2cap_send_disconn_req(struct l2cap_chan *chan, int err)
1381{
1382	struct l2cap_conn *conn = chan->conn;
1383	struct l2cap_disconn_req req;
1384
1385	if (!conn)
1386		return;
1387
1388	if (chan->mode == L2CAP_MODE_ERTM && chan->state == BT_CONNECTED) {
1389		__clear_retrans_timer(chan);
1390		__clear_monitor_timer(chan);
1391		__clear_ack_timer(chan);
1392	}
1393
1394	if (chan->scid == L2CAP_CID_A2MP) {
1395		l2cap_state_change(chan, BT_DISCONN);
1396		return;
1397	}
1398
1399	req.dcid = cpu_to_le16(chan->dcid);
1400	req.scid = cpu_to_le16(chan->scid);
1401	l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_DISCONN_REQ,
1402		       sizeof(req), &req);
1403
1404	l2cap_state_change_and_error(chan, BT_DISCONN, err);
1405}
1406
1407/* ---- L2CAP connections ---- */
1408static void l2cap_conn_start(struct l2cap_conn *conn)
1409{
1410	struct l2cap_chan *chan, *tmp;
1411
1412	BT_DBG("conn %p", conn);
1413
1414	mutex_lock(&conn->chan_lock);
1415
1416	list_for_each_entry_safe(chan, tmp, &conn->chan_l, list) {
1417		l2cap_chan_lock(chan);
1418
1419		if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
1420			l2cap_chan_ready(chan);
1421			l2cap_chan_unlock(chan);
1422			continue;
1423		}
1424
1425		if (chan->state == BT_CONNECT) {
1426			if (!l2cap_chan_check_security(chan, true) ||
1427			    !__l2cap_no_conn_pending(chan)) {
1428				l2cap_chan_unlock(chan);
1429				continue;
1430			}
1431
1432			if (!l2cap_mode_supported(chan->mode, conn->feat_mask)
1433			    && test_bit(CONF_STATE2_DEVICE,
1434					&chan->conf_state)) {
1435				l2cap_chan_close(chan, ECONNRESET);
1436				l2cap_chan_unlock(chan);
1437				continue;
1438			}
1439
1440			l2cap_start_connection(chan);
 
 
 
1441
1442		} else if (chan->state == BT_CONNECT2) {
1443			struct l2cap_conn_rsp rsp;
1444			char buf[128];
1445			rsp.scid = cpu_to_le16(chan->dcid);
1446			rsp.dcid = cpu_to_le16(chan->scid);
1447
1448			if (l2cap_chan_check_security(chan, false)) {
1449				if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
1450					rsp.result = cpu_to_le16(L2CAP_CR_PEND);
1451					rsp.status = cpu_to_le16(L2CAP_CS_AUTHOR_PEND);
1452					chan->ops->defer(chan);
1453
1454				} else {
1455					l2cap_state_change(chan, BT_CONFIG);
1456					rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
1457					rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
1458				}
1459			} else {
1460				rsp.result = cpu_to_le16(L2CAP_CR_PEND);
1461				rsp.status = cpu_to_le16(L2CAP_CS_AUTHEN_PEND);
1462			}
1463
1464			l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP,
1465				       sizeof(rsp), &rsp);
1466
1467			if (test_bit(CONF_REQ_SENT, &chan->conf_state) ||
1468			    rsp.result != L2CAP_CR_SUCCESS) {
1469				l2cap_chan_unlock(chan);
1470				continue;
1471			}
1472
1473			set_bit(CONF_REQ_SENT, &chan->conf_state);
1474			l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
1475				       l2cap_build_conf_req(chan, buf), buf);
1476			chan->num_conf_req++;
1477		}
1478
1479		l2cap_chan_unlock(chan);
1480	}
1481
1482	mutex_unlock(&conn->chan_lock);
1483}
1484
1485static void l2cap_le_conn_ready(struct l2cap_conn *conn)
1486{
1487	struct hci_conn *hcon = conn->hcon;
1488	struct hci_dev *hdev = hcon->hdev;
1489
1490	BT_DBG("%s conn %p", hdev->name, conn);
1491
1492	/* For outgoing pairing which doesn't necessarily have an
1493	 * associated socket (e.g. mgmt_pair_device).
1494	 */
1495	if (hcon->out)
1496		smp_conn_security(hcon, hcon->pending_sec_level);
1497
1498	/* For LE slave connections, make sure the connection interval
1499	 * is in the range of the minium and maximum interval that has
1500	 * been configured for this connection. If not, then trigger
1501	 * the connection update procedure.
1502	 */
1503	if (hcon->role == HCI_ROLE_SLAVE &&
1504	    (hcon->le_conn_interval < hcon->le_conn_min_interval ||
1505	     hcon->le_conn_interval > hcon->le_conn_max_interval)) {
1506		struct l2cap_conn_param_update_req req;
1507
1508		req.min = cpu_to_le16(hcon->le_conn_min_interval);
1509		req.max = cpu_to_le16(hcon->le_conn_max_interval);
1510		req.latency = cpu_to_le16(hcon->le_conn_latency);
1511		req.to_multiplier = cpu_to_le16(hcon->le_supv_timeout);
1512
1513		l2cap_send_cmd(conn, l2cap_get_ident(conn),
1514			       L2CAP_CONN_PARAM_UPDATE_REQ, sizeof(req), &req);
1515	}
1516}
1517
1518static void l2cap_conn_ready(struct l2cap_conn *conn)
1519{
1520	struct l2cap_chan *chan;
1521	struct hci_conn *hcon = conn->hcon;
1522
1523	BT_DBG("conn %p", conn);
1524
1525	if (hcon->type == ACL_LINK)
1526		l2cap_request_info(conn);
1527
1528	mutex_lock(&conn->chan_lock);
1529
1530	list_for_each_entry(chan, &conn->chan_l, list) {
1531
1532		l2cap_chan_lock(chan);
1533
1534		if (chan->scid == L2CAP_CID_A2MP) {
1535			l2cap_chan_unlock(chan);
1536			continue;
1537		}
1538
1539		if (hcon->type == LE_LINK) {
1540			l2cap_le_start(chan);
1541		} else if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
1542			if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE)
1543				l2cap_chan_ready(chan);
1544		} else if (chan->state == BT_CONNECT) {
1545			l2cap_do_start(chan);
1546		}
1547
1548		l2cap_chan_unlock(chan);
1549	}
1550
1551	mutex_unlock(&conn->chan_lock);
1552
1553	if (hcon->type == LE_LINK)
1554		l2cap_le_conn_ready(conn);
1555
1556	queue_work(hcon->hdev->workqueue, &conn->pending_rx_work);
1557}
1558
1559/* Notify sockets that we cannot guaranty reliability anymore */
1560static void l2cap_conn_unreliable(struct l2cap_conn *conn, int err)
1561{
1562	struct l2cap_chan *chan;
1563
1564	BT_DBG("conn %p", conn);
1565
1566	mutex_lock(&conn->chan_lock);
1567
1568	list_for_each_entry(chan, &conn->chan_l, list) {
1569		if (test_bit(FLAG_FORCE_RELIABLE, &chan->flags))
1570			l2cap_chan_set_err(chan, err);
1571	}
1572
1573	mutex_unlock(&conn->chan_lock);
1574}
1575
1576static void l2cap_info_timeout(struct work_struct *work)
1577{
1578	struct l2cap_conn *conn = container_of(work, struct l2cap_conn,
1579					       info_timer.work);
1580
1581	conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
1582	conn->info_ident = 0;
1583
1584	l2cap_conn_start(conn);
1585}
1586
1587/*
1588 * l2cap_user
1589 * External modules can register l2cap_user objects on l2cap_conn. The ->probe
1590 * callback is called during registration. The ->remove callback is called
1591 * during unregistration.
1592 * An l2cap_user object can either be explicitly unregistered or when the
1593 * underlying l2cap_conn object is deleted. This guarantees that l2cap->hcon,
1594 * l2cap->hchan, .. are valid as long as the remove callback hasn't been called.
1595 * External modules must own a reference to the l2cap_conn object if they intend
1596 * to call l2cap_unregister_user(). The l2cap_conn object might get destroyed at
1597 * any time if they don't.
1598 */
1599
1600int l2cap_register_user(struct l2cap_conn *conn, struct l2cap_user *user)
1601{
1602	struct hci_dev *hdev = conn->hcon->hdev;
1603	int ret;
1604
1605	/* We need to check whether l2cap_conn is registered. If it is not, we
1606	 * must not register the l2cap_user. l2cap_conn_del() is unregisters
1607	 * l2cap_conn objects, but doesn't provide its own locking. Instead, it
1608	 * relies on the parent hci_conn object to be locked. This itself relies
1609	 * on the hci_dev object to be locked. So we must lock the hci device
1610	 * here, too. */
1611
1612	hci_dev_lock(hdev);
1613
1614	if (!list_empty(&user->list)) {
1615		ret = -EINVAL;
1616		goto out_unlock;
1617	}
1618
1619	/* conn->hchan is NULL after l2cap_conn_del() was called */
1620	if (!conn->hchan) {
1621		ret = -ENODEV;
1622		goto out_unlock;
1623	}
1624
1625	ret = user->probe(conn, user);
1626	if (ret)
1627		goto out_unlock;
1628
1629	list_add(&user->list, &conn->users);
1630	ret = 0;
1631
1632out_unlock:
1633	hci_dev_unlock(hdev);
1634	return ret;
1635}
1636EXPORT_SYMBOL(l2cap_register_user);
1637
1638void l2cap_unregister_user(struct l2cap_conn *conn, struct l2cap_user *user)
1639{
1640	struct hci_dev *hdev = conn->hcon->hdev;
1641
1642	hci_dev_lock(hdev);
1643
1644	if (list_empty(&user->list))
1645		goto out_unlock;
1646
1647	list_del_init(&user->list);
1648	user->remove(conn, user);
1649
1650out_unlock:
1651	hci_dev_unlock(hdev);
1652}
1653EXPORT_SYMBOL(l2cap_unregister_user);
1654
1655static void l2cap_unregister_all_users(struct l2cap_conn *conn)
1656{
1657	struct l2cap_user *user;
1658
1659	while (!list_empty(&conn->users)) {
1660		user = list_first_entry(&conn->users, struct l2cap_user, list);
1661		list_del_init(&user->list);
1662		user->remove(conn, user);
1663	}
1664}
1665
1666static void l2cap_conn_del(struct hci_conn *hcon, int err)
1667{
1668	struct l2cap_conn *conn = hcon->l2cap_data;
1669	struct l2cap_chan *chan, *l;
1670
1671	if (!conn)
1672		return;
1673
1674	BT_DBG("hcon %p conn %p, err %d", hcon, conn, err);
1675
1676	kfree_skb(conn->rx_skb);
1677
1678	skb_queue_purge(&conn->pending_rx);
1679
1680	/* We can not call flush_work(&conn->pending_rx_work) here since we
1681	 * might block if we are running on a worker from the same workqueue
1682	 * pending_rx_work is waiting on.
1683	 */
1684	if (work_pending(&conn->pending_rx_work))
1685		cancel_work_sync(&conn->pending_rx_work);
1686
1687	if (work_pending(&conn->id_addr_update_work))
1688		cancel_work_sync(&conn->id_addr_update_work);
1689
1690	l2cap_unregister_all_users(conn);
1691
1692	/* Force the connection to be immediately dropped */
1693	hcon->disc_timeout = 0;
1694
1695	mutex_lock(&conn->chan_lock);
1696
1697	/* Kill channels */
1698	list_for_each_entry_safe(chan, l, &conn->chan_l, list) {
1699		l2cap_chan_hold(chan);
1700		l2cap_chan_lock(chan);
1701
1702		l2cap_chan_del(chan, err);
1703
1704		l2cap_chan_unlock(chan);
1705
1706		chan->ops->close(chan);
 
 
1707		l2cap_chan_put(chan);
1708	}
1709
1710	mutex_unlock(&conn->chan_lock);
1711
1712	hci_chan_del(conn->hchan);
1713
1714	if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT)
1715		cancel_delayed_work_sync(&conn->info_timer);
1716
1717	hcon->l2cap_data = NULL;
1718	conn->hchan = NULL;
1719	l2cap_conn_put(conn);
1720}
1721
1722static void l2cap_conn_free(struct kref *ref)
1723{
1724	struct l2cap_conn *conn = container_of(ref, struct l2cap_conn, ref);
1725
1726	hci_conn_put(conn->hcon);
1727	kfree(conn);
1728}
1729
1730struct l2cap_conn *l2cap_conn_get(struct l2cap_conn *conn)
1731{
1732	kref_get(&conn->ref);
1733	return conn;
1734}
1735EXPORT_SYMBOL(l2cap_conn_get);
1736
1737void l2cap_conn_put(struct l2cap_conn *conn)
1738{
1739	kref_put(&conn->ref, l2cap_conn_free);
1740}
1741EXPORT_SYMBOL(l2cap_conn_put);
1742
1743/* ---- Socket interface ---- */
1744
1745/* Find socket with psm and source / destination bdaddr.
1746 * Returns closest match.
1747 */
1748static struct l2cap_chan *l2cap_global_chan_by_psm(int state, __le16 psm,
1749						   bdaddr_t *src,
1750						   bdaddr_t *dst,
1751						   u8 link_type)
1752{
1753	struct l2cap_chan *c, *c1 = NULL;
1754
1755	read_lock(&chan_list_lock);
1756
1757	list_for_each_entry(c, &chan_list, global_l) {
1758		if (state && c->state != state)
1759			continue;
1760
1761		if (link_type == ACL_LINK && c->src_type != BDADDR_BREDR)
1762			continue;
1763
1764		if (link_type == LE_LINK && c->src_type == BDADDR_BREDR)
1765			continue;
1766
1767		if (c->psm == psm) {
1768			int src_match, dst_match;
1769			int src_any, dst_any;
1770
1771			/* Exact match. */
1772			src_match = !bacmp(&c->src, src);
1773			dst_match = !bacmp(&c->dst, dst);
1774			if (src_match && dst_match) {
1775				l2cap_chan_hold(c);
1776				read_unlock(&chan_list_lock);
1777				return c;
1778			}
1779
1780			/* Closest match */
1781			src_any = !bacmp(&c->src, BDADDR_ANY);
1782			dst_any = !bacmp(&c->dst, BDADDR_ANY);
1783			if ((src_match && dst_any) || (src_any && dst_match) ||
1784			    (src_any && dst_any))
1785				c1 = c;
1786		}
1787	}
1788
1789	if (c1)
1790		l2cap_chan_hold(c1);
1791
1792	read_unlock(&chan_list_lock);
1793
1794	return c1;
1795}
1796
1797static void l2cap_monitor_timeout(struct work_struct *work)
1798{
1799	struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
1800					       monitor_timer.work);
1801
1802	BT_DBG("chan %p", chan);
1803
1804	l2cap_chan_lock(chan);
1805
1806	if (!chan->conn) {
1807		l2cap_chan_unlock(chan);
1808		l2cap_chan_put(chan);
1809		return;
1810	}
1811
1812	l2cap_tx(chan, NULL, NULL, L2CAP_EV_MONITOR_TO);
1813
1814	l2cap_chan_unlock(chan);
1815	l2cap_chan_put(chan);
1816}
1817
1818static void l2cap_retrans_timeout(struct work_struct *work)
1819{
1820	struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
1821					       retrans_timer.work);
1822
1823	BT_DBG("chan %p", chan);
1824
1825	l2cap_chan_lock(chan);
1826
1827	if (!chan->conn) {
1828		l2cap_chan_unlock(chan);
1829		l2cap_chan_put(chan);
1830		return;
1831	}
1832
1833	l2cap_tx(chan, NULL, NULL, L2CAP_EV_RETRANS_TO);
1834	l2cap_chan_unlock(chan);
1835	l2cap_chan_put(chan);
1836}
1837
1838static void l2cap_streaming_send(struct l2cap_chan *chan,
1839				 struct sk_buff_head *skbs)
1840{
1841	struct sk_buff *skb;
1842	struct l2cap_ctrl *control;
1843
1844	BT_DBG("chan %p, skbs %p", chan, skbs);
1845
1846	if (__chan_is_moving(chan))
1847		return;
1848
1849	skb_queue_splice_tail_init(skbs, &chan->tx_q);
1850
1851	while (!skb_queue_empty(&chan->tx_q)) {
1852
1853		skb = skb_dequeue(&chan->tx_q);
1854
1855		bt_cb(skb)->l2cap.retries = 1;
1856		control = &bt_cb(skb)->l2cap;
1857
1858		control->reqseq = 0;
1859		control->txseq = chan->next_tx_seq;
1860
1861		__pack_control(chan, control, skb);
1862
1863		if (chan->fcs == L2CAP_FCS_CRC16) {
1864			u16 fcs = crc16(0, (u8 *) skb->data, skb->len);
1865			put_unaligned_le16(fcs, skb_put(skb, L2CAP_FCS_SIZE));
1866		}
1867
1868		l2cap_do_send(chan, skb);
1869
1870		BT_DBG("Sent txseq %u", control->txseq);
1871
1872		chan->next_tx_seq = __next_seq(chan, chan->next_tx_seq);
1873		chan->frames_sent++;
1874	}
1875}
1876
1877static int l2cap_ertm_send(struct l2cap_chan *chan)
1878{
1879	struct sk_buff *skb, *tx_skb;
1880	struct l2cap_ctrl *control;
1881	int sent = 0;
1882
1883	BT_DBG("chan %p", chan);
1884
1885	if (chan->state != BT_CONNECTED)
1886		return -ENOTCONN;
1887
1888	if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state))
1889		return 0;
1890
1891	if (__chan_is_moving(chan))
1892		return 0;
1893
1894	while (chan->tx_send_head &&
1895	       chan->unacked_frames < chan->remote_tx_win &&
1896	       chan->tx_state == L2CAP_TX_STATE_XMIT) {
1897
1898		skb = chan->tx_send_head;
1899
1900		bt_cb(skb)->l2cap.retries = 1;
1901		control = &bt_cb(skb)->l2cap;
1902
1903		if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state))
1904			control->final = 1;
1905
1906		control->reqseq = chan->buffer_seq;
1907		chan->last_acked_seq = chan->buffer_seq;
1908		control->txseq = chan->next_tx_seq;
1909
1910		__pack_control(chan, control, skb);
1911
1912		if (chan->fcs == L2CAP_FCS_CRC16) {
1913			u16 fcs = crc16(0, (u8 *) skb->data, skb->len);
1914			put_unaligned_le16(fcs, skb_put(skb, L2CAP_FCS_SIZE));
1915		}
1916
1917		/* Clone after data has been modified. Data is assumed to be
1918		   read-only (for locking purposes) on cloned sk_buffs.
1919		 */
1920		tx_skb = skb_clone(skb, GFP_KERNEL);
1921
1922		if (!tx_skb)
1923			break;
1924
1925		__set_retrans_timer(chan);
1926
1927		chan->next_tx_seq = __next_seq(chan, chan->next_tx_seq);
1928		chan->unacked_frames++;
1929		chan->frames_sent++;
1930		sent++;
1931
1932		if (skb_queue_is_last(&chan->tx_q, skb))
1933			chan->tx_send_head = NULL;
1934		else
1935			chan->tx_send_head = skb_queue_next(&chan->tx_q, skb);
1936
1937		l2cap_do_send(chan, tx_skb);
1938		BT_DBG("Sent txseq %u", control->txseq);
1939	}
1940
1941	BT_DBG("Sent %d, %u unacked, %u in ERTM queue", sent,
1942	       chan->unacked_frames, skb_queue_len(&chan->tx_q));
1943
1944	return sent;
1945}
1946
1947static void l2cap_ertm_resend(struct l2cap_chan *chan)
1948{
1949	struct l2cap_ctrl control;
1950	struct sk_buff *skb;
1951	struct sk_buff *tx_skb;
1952	u16 seq;
1953
1954	BT_DBG("chan %p", chan);
1955
1956	if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state))
1957		return;
1958
1959	if (__chan_is_moving(chan))
1960		return;
1961
1962	while (chan->retrans_list.head != L2CAP_SEQ_LIST_CLEAR) {
1963		seq = l2cap_seq_list_pop(&chan->retrans_list);
1964
1965		skb = l2cap_ertm_seq_in_queue(&chan->tx_q, seq);
1966		if (!skb) {
1967			BT_DBG("Error: Can't retransmit seq %d, frame missing",
1968			       seq);
1969			continue;
1970		}
1971
1972		bt_cb(skb)->l2cap.retries++;
1973		control = bt_cb(skb)->l2cap;
1974
1975		if (chan->max_tx != 0 &&
1976		    bt_cb(skb)->l2cap.retries > chan->max_tx) {
1977			BT_DBG("Retry limit exceeded (%d)", chan->max_tx);
1978			l2cap_send_disconn_req(chan, ECONNRESET);
1979			l2cap_seq_list_clear(&chan->retrans_list);
1980			break;
1981		}
1982
1983		control.reqseq = chan->buffer_seq;
1984		if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state))
1985			control.final = 1;
1986		else
1987			control.final = 0;
1988
1989		if (skb_cloned(skb)) {
1990			/* Cloned sk_buffs are read-only, so we need a
1991			 * writeable copy
1992			 */
1993			tx_skb = skb_copy(skb, GFP_KERNEL);
1994		} else {
1995			tx_skb = skb_clone(skb, GFP_KERNEL);
1996		}
1997
1998		if (!tx_skb) {
1999			l2cap_seq_list_clear(&chan->retrans_list);
2000			break;
2001		}
2002
2003		/* Update skb contents */
2004		if (test_bit(FLAG_EXT_CTRL, &chan->flags)) {
2005			put_unaligned_le32(__pack_extended_control(&control),
2006					   tx_skb->data + L2CAP_HDR_SIZE);
2007		} else {
2008			put_unaligned_le16(__pack_enhanced_control(&control),
2009					   tx_skb->data + L2CAP_HDR_SIZE);
2010		}
2011
2012		/* Update FCS */
2013		if (chan->fcs == L2CAP_FCS_CRC16) {
2014			u16 fcs = crc16(0, (u8 *) tx_skb->data,
2015					tx_skb->len - L2CAP_FCS_SIZE);
2016			put_unaligned_le16(fcs, skb_tail_pointer(tx_skb) -
2017						L2CAP_FCS_SIZE);
2018		}
2019
2020		l2cap_do_send(chan, tx_skb);
2021
2022		BT_DBG("Resent txseq %d", control.txseq);
2023
2024		chan->last_acked_seq = chan->buffer_seq;
2025	}
2026}
2027
2028static void l2cap_retransmit(struct l2cap_chan *chan,
2029			     struct l2cap_ctrl *control)
2030{
2031	BT_DBG("chan %p, control %p", chan, control);
2032
2033	l2cap_seq_list_append(&chan->retrans_list, control->reqseq);
2034	l2cap_ertm_resend(chan);
2035}
2036
2037static void l2cap_retransmit_all(struct l2cap_chan *chan,
2038				 struct l2cap_ctrl *control)
2039{
2040	struct sk_buff *skb;
2041
2042	BT_DBG("chan %p, control %p", chan, control);
2043
2044	if (control->poll)
2045		set_bit(CONN_SEND_FBIT, &chan->conn_state);
2046
2047	l2cap_seq_list_clear(&chan->retrans_list);
2048
2049	if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state))
2050		return;
2051
2052	if (chan->unacked_frames) {
2053		skb_queue_walk(&chan->tx_q, skb) {
2054			if (bt_cb(skb)->l2cap.txseq == control->reqseq ||
2055			    skb == chan->tx_send_head)
2056				break;
2057		}
2058
2059		skb_queue_walk_from(&chan->tx_q, skb) {
2060			if (skb == chan->tx_send_head)
2061				break;
2062
2063			l2cap_seq_list_append(&chan->retrans_list,
2064					      bt_cb(skb)->l2cap.txseq);
2065		}
2066
2067		l2cap_ertm_resend(chan);
2068	}
2069}
2070
2071static void l2cap_send_ack(struct l2cap_chan *chan)
2072{
2073	struct l2cap_ctrl control;
2074	u16 frames_to_ack = __seq_offset(chan, chan->buffer_seq,
2075					 chan->last_acked_seq);
2076	int threshold;
2077
2078	BT_DBG("chan %p last_acked_seq %d buffer_seq %d",
2079	       chan, chan->last_acked_seq, chan->buffer_seq);
2080
2081	memset(&control, 0, sizeof(control));
2082	control.sframe = 1;
2083
2084	if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state) &&
2085	    chan->rx_state == L2CAP_RX_STATE_RECV) {
2086		__clear_ack_timer(chan);
2087		control.super = L2CAP_SUPER_RNR;
2088		control.reqseq = chan->buffer_seq;
2089		l2cap_send_sframe(chan, &control);
2090	} else {
2091		if (!test_bit(CONN_REMOTE_BUSY, &chan->conn_state)) {
2092			l2cap_ertm_send(chan);
2093			/* If any i-frames were sent, they included an ack */
2094			if (chan->buffer_seq == chan->last_acked_seq)
2095				frames_to_ack = 0;
2096		}
2097
2098		/* Ack now if the window is 3/4ths full.
2099		 * Calculate without mul or div
2100		 */
2101		threshold = chan->ack_win;
2102		threshold += threshold << 1;
2103		threshold >>= 2;
2104
2105		BT_DBG("frames_to_ack %u, threshold %d", frames_to_ack,
2106		       threshold);
2107
2108		if (frames_to_ack >= threshold) {
2109			__clear_ack_timer(chan);
2110			control.super = L2CAP_SUPER_RR;
2111			control.reqseq = chan->buffer_seq;
2112			l2cap_send_sframe(chan, &control);
2113			frames_to_ack = 0;
2114		}
2115
2116		if (frames_to_ack)
2117			__set_ack_timer(chan);
2118	}
2119}
2120
2121static inline int l2cap_skbuff_fromiovec(struct l2cap_chan *chan,
2122					 struct msghdr *msg, int len,
2123					 int count, struct sk_buff *skb)
2124{
2125	struct l2cap_conn *conn = chan->conn;
2126	struct sk_buff **frag;
2127	int sent = 0;
2128
2129	if (copy_from_iter(skb_put(skb, count), count, &msg->msg_iter) != count)
2130		return -EFAULT;
2131
2132	sent += count;
2133	len  -= count;
2134
2135	/* Continuation fragments (no L2CAP header) */
2136	frag = &skb_shinfo(skb)->frag_list;
2137	while (len) {
2138		struct sk_buff *tmp;
2139
2140		count = min_t(unsigned int, conn->mtu, len);
2141
2142		tmp = chan->ops->alloc_skb(chan, 0, count,
2143					   msg->msg_flags & MSG_DONTWAIT);
2144		if (IS_ERR(tmp))
2145			return PTR_ERR(tmp);
2146
2147		*frag = tmp;
2148
2149		if (copy_from_iter(skb_put(*frag, count), count,
2150				   &msg->msg_iter) != count)
2151			return -EFAULT;
2152
2153		sent += count;
2154		len  -= count;
2155
2156		skb->len += (*frag)->len;
2157		skb->data_len += (*frag)->len;
2158
2159		frag = &(*frag)->next;
2160	}
2161
2162	return sent;
2163}
2164
2165static struct sk_buff *l2cap_create_connless_pdu(struct l2cap_chan *chan,
2166						 struct msghdr *msg, size_t len)
2167{
2168	struct l2cap_conn *conn = chan->conn;
2169	struct sk_buff *skb;
2170	int err, count, hlen = L2CAP_HDR_SIZE + L2CAP_PSMLEN_SIZE;
2171	struct l2cap_hdr *lh;
2172
2173	BT_DBG("chan %p psm 0x%2.2x len %zu", chan,
2174	       __le16_to_cpu(chan->psm), len);
2175
2176	count = min_t(unsigned int, (conn->mtu - hlen), len);
2177
2178	skb = chan->ops->alloc_skb(chan, hlen, count,
2179				   msg->msg_flags & MSG_DONTWAIT);
2180	if (IS_ERR(skb))
2181		return skb;
2182
2183	/* Create L2CAP header */
2184	lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
2185	lh->cid = cpu_to_le16(chan->dcid);
2186	lh->len = cpu_to_le16(len + L2CAP_PSMLEN_SIZE);
2187	put_unaligned(chan->psm, (__le16 *) skb_put(skb, L2CAP_PSMLEN_SIZE));
2188
2189	err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2190	if (unlikely(err < 0)) {
2191		kfree_skb(skb);
2192		return ERR_PTR(err);
2193	}
2194	return skb;
2195}
2196
2197static struct sk_buff *l2cap_create_basic_pdu(struct l2cap_chan *chan,
2198					      struct msghdr *msg, size_t len)
2199{
2200	struct l2cap_conn *conn = chan->conn;
2201	struct sk_buff *skb;
2202	int err, count;
2203	struct l2cap_hdr *lh;
2204
2205	BT_DBG("chan %p len %zu", chan, len);
2206
2207	count = min_t(unsigned int, (conn->mtu - L2CAP_HDR_SIZE), len);
2208
2209	skb = chan->ops->alloc_skb(chan, L2CAP_HDR_SIZE, count,
2210				   msg->msg_flags & MSG_DONTWAIT);
2211	if (IS_ERR(skb))
2212		return skb;
2213
2214	/* Create L2CAP header */
2215	lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
2216	lh->cid = cpu_to_le16(chan->dcid);
2217	lh->len = cpu_to_le16(len);
2218
2219	err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2220	if (unlikely(err < 0)) {
2221		kfree_skb(skb);
2222		return ERR_PTR(err);
2223	}
2224	return skb;
2225}
2226
2227static struct sk_buff *l2cap_create_iframe_pdu(struct l2cap_chan *chan,
2228					       struct msghdr *msg, size_t len,
2229					       u16 sdulen)
2230{
2231	struct l2cap_conn *conn = chan->conn;
2232	struct sk_buff *skb;
2233	int err, count, hlen;
2234	struct l2cap_hdr *lh;
2235
2236	BT_DBG("chan %p len %zu", chan, len);
2237
2238	if (!conn)
2239		return ERR_PTR(-ENOTCONN);
2240
2241	hlen = __ertm_hdr_size(chan);
2242
2243	if (sdulen)
2244		hlen += L2CAP_SDULEN_SIZE;
2245
2246	if (chan->fcs == L2CAP_FCS_CRC16)
2247		hlen += L2CAP_FCS_SIZE;
2248
2249	count = min_t(unsigned int, (conn->mtu - hlen), len);
2250
2251	skb = chan->ops->alloc_skb(chan, hlen, count,
2252				   msg->msg_flags & MSG_DONTWAIT);
2253	if (IS_ERR(skb))
2254		return skb;
2255
2256	/* Create L2CAP header */
2257	lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
2258	lh->cid = cpu_to_le16(chan->dcid);
2259	lh->len = cpu_to_le16(len + (hlen - L2CAP_HDR_SIZE));
2260
2261	/* Control header is populated later */
2262	if (test_bit(FLAG_EXT_CTRL, &chan->flags))
2263		put_unaligned_le32(0, skb_put(skb, L2CAP_EXT_CTRL_SIZE));
2264	else
2265		put_unaligned_le16(0, skb_put(skb, L2CAP_ENH_CTRL_SIZE));
2266
2267	if (sdulen)
2268		put_unaligned_le16(sdulen, skb_put(skb, L2CAP_SDULEN_SIZE));
2269
2270	err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2271	if (unlikely(err < 0)) {
2272		kfree_skb(skb);
2273		return ERR_PTR(err);
2274	}
2275
2276	bt_cb(skb)->l2cap.fcs = chan->fcs;
2277	bt_cb(skb)->l2cap.retries = 0;
2278	return skb;
2279}
2280
2281static int l2cap_segment_sdu(struct l2cap_chan *chan,
2282			     struct sk_buff_head *seg_queue,
2283			     struct msghdr *msg, size_t len)
2284{
2285	struct sk_buff *skb;
2286	u16 sdu_len;
2287	size_t pdu_len;
2288	u8 sar;
2289
2290	BT_DBG("chan %p, msg %p, len %zu", chan, msg, len);
2291
2292	/* It is critical that ERTM PDUs fit in a single HCI fragment,
2293	 * so fragmented skbs are not used.  The HCI layer's handling
2294	 * of fragmented skbs is not compatible with ERTM's queueing.
2295	 */
2296
2297	/* PDU size is derived from the HCI MTU */
2298	pdu_len = chan->conn->mtu;
2299
2300	/* Constrain PDU size for BR/EDR connections */
2301	if (!chan->hs_hcon)
2302		pdu_len = min_t(size_t, pdu_len, L2CAP_BREDR_MAX_PAYLOAD);
2303
2304	/* Adjust for largest possible L2CAP overhead. */
2305	if (chan->fcs)
2306		pdu_len -= L2CAP_FCS_SIZE;
2307
2308	pdu_len -= __ertm_hdr_size(chan);
2309
2310	/* Remote device may have requested smaller PDUs */
2311	pdu_len = min_t(size_t, pdu_len, chan->remote_mps);
2312
2313	if (len <= pdu_len) {
2314		sar = L2CAP_SAR_UNSEGMENTED;
2315		sdu_len = 0;
2316		pdu_len = len;
2317	} else {
2318		sar = L2CAP_SAR_START;
2319		sdu_len = len;
2320	}
2321
2322	while (len > 0) {
2323		skb = l2cap_create_iframe_pdu(chan, msg, pdu_len, sdu_len);
2324
2325		if (IS_ERR(skb)) {
2326			__skb_queue_purge(seg_queue);
2327			return PTR_ERR(skb);
2328		}
2329
2330		bt_cb(skb)->l2cap.sar = sar;
2331		__skb_queue_tail(seg_queue, skb);
2332
2333		len -= pdu_len;
2334		if (sdu_len)
2335			sdu_len = 0;
2336
2337		if (len <= pdu_len) {
2338			sar = L2CAP_SAR_END;
2339			pdu_len = len;
2340		} else {
2341			sar = L2CAP_SAR_CONTINUE;
2342		}
2343	}
2344
2345	return 0;
2346}
2347
2348static struct sk_buff *l2cap_create_le_flowctl_pdu(struct l2cap_chan *chan,
2349						   struct msghdr *msg,
2350						   size_t len, u16 sdulen)
2351{
2352	struct l2cap_conn *conn = chan->conn;
2353	struct sk_buff *skb;
2354	int err, count, hlen;
2355	struct l2cap_hdr *lh;
2356
2357	BT_DBG("chan %p len %zu", chan, len);
2358
2359	if (!conn)
2360		return ERR_PTR(-ENOTCONN);
2361
2362	hlen = L2CAP_HDR_SIZE;
2363
2364	if (sdulen)
2365		hlen += L2CAP_SDULEN_SIZE;
2366
2367	count = min_t(unsigned int, (conn->mtu - hlen), len);
2368
2369	skb = chan->ops->alloc_skb(chan, hlen, count,
2370				   msg->msg_flags & MSG_DONTWAIT);
2371	if (IS_ERR(skb))
2372		return skb;
2373
2374	/* Create L2CAP header */
2375	lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
2376	lh->cid = cpu_to_le16(chan->dcid);
2377	lh->len = cpu_to_le16(len + (hlen - L2CAP_HDR_SIZE));
2378
2379	if (sdulen)
2380		put_unaligned_le16(sdulen, skb_put(skb, L2CAP_SDULEN_SIZE));
2381
2382	err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2383	if (unlikely(err < 0)) {
2384		kfree_skb(skb);
2385		return ERR_PTR(err);
2386	}
2387
2388	return skb;
2389}
2390
2391static int l2cap_segment_le_sdu(struct l2cap_chan *chan,
2392				struct sk_buff_head *seg_queue,
2393				struct msghdr *msg, size_t len)
2394{
2395	struct sk_buff *skb;
2396	size_t pdu_len;
2397	u16 sdu_len;
2398
2399	BT_DBG("chan %p, msg %p, len %zu", chan, msg, len);
2400
2401	sdu_len = len;
2402	pdu_len = chan->remote_mps - L2CAP_SDULEN_SIZE;
2403
2404	while (len > 0) {
2405		if (len <= pdu_len)
2406			pdu_len = len;
2407
2408		skb = l2cap_create_le_flowctl_pdu(chan, msg, pdu_len, sdu_len);
2409		if (IS_ERR(skb)) {
2410			__skb_queue_purge(seg_queue);
2411			return PTR_ERR(skb);
2412		}
2413
2414		__skb_queue_tail(seg_queue, skb);
2415
2416		len -= pdu_len;
2417
2418		if (sdu_len) {
2419			sdu_len = 0;
2420			pdu_len += L2CAP_SDULEN_SIZE;
2421		}
2422	}
2423
2424	return 0;
2425}
2426
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2427int l2cap_chan_send(struct l2cap_chan *chan, struct msghdr *msg, size_t len)
2428{
2429	struct sk_buff *skb;
2430	int err;
2431	struct sk_buff_head seg_queue;
2432
2433	if (!chan->conn)
2434		return -ENOTCONN;
2435
2436	/* Connectionless channel */
2437	if (chan->chan_type == L2CAP_CHAN_CONN_LESS) {
2438		skb = l2cap_create_connless_pdu(chan, msg, len);
2439		if (IS_ERR(skb))
2440			return PTR_ERR(skb);
2441
2442		/* Channel lock is released before requesting new skb and then
2443		 * reacquired thus we need to recheck channel state.
2444		 */
2445		if (chan->state != BT_CONNECTED) {
2446			kfree_skb(skb);
2447			return -ENOTCONN;
2448		}
2449
2450		l2cap_do_send(chan, skb);
2451		return len;
2452	}
2453
2454	switch (chan->mode) {
2455	case L2CAP_MODE_LE_FLOWCTL:
 
2456		/* Check outgoing MTU */
2457		if (len > chan->omtu)
2458			return -EMSGSIZE;
2459
2460		if (!chan->tx_credits)
2461			return -EAGAIN;
2462
2463		__skb_queue_head_init(&seg_queue);
2464
2465		err = l2cap_segment_le_sdu(chan, &seg_queue, msg, len);
2466
2467		if (chan->state != BT_CONNECTED) {
2468			__skb_queue_purge(&seg_queue);
2469			err = -ENOTCONN;
2470		}
2471
2472		if (err)
2473			return err;
2474
2475		skb_queue_splice_tail_init(&seg_queue, &chan->tx_q);
2476
2477		while (chan->tx_credits && !skb_queue_empty(&chan->tx_q)) {
2478			l2cap_do_send(chan, skb_dequeue(&chan->tx_q));
2479			chan->tx_credits--;
2480		}
2481
2482		if (!chan->tx_credits)
2483			chan->ops->suspend(chan);
2484
2485		err = len;
2486
2487		break;
2488
2489	case L2CAP_MODE_BASIC:
2490		/* Check outgoing MTU */
2491		if (len > chan->omtu)
2492			return -EMSGSIZE;
2493
2494		/* Create a basic PDU */
2495		skb = l2cap_create_basic_pdu(chan, msg, len);
2496		if (IS_ERR(skb))
2497			return PTR_ERR(skb);
2498
2499		/* Channel lock is released before requesting new skb and then
2500		 * reacquired thus we need to recheck channel state.
2501		 */
2502		if (chan->state != BT_CONNECTED) {
2503			kfree_skb(skb);
2504			return -ENOTCONN;
2505		}
2506
2507		l2cap_do_send(chan, skb);
2508		err = len;
2509		break;
2510
2511	case L2CAP_MODE_ERTM:
2512	case L2CAP_MODE_STREAMING:
2513		/* Check outgoing MTU */
2514		if (len > chan->omtu) {
2515			err = -EMSGSIZE;
2516			break;
2517		}
2518
2519		__skb_queue_head_init(&seg_queue);
2520
2521		/* Do segmentation before calling in to the state machine,
2522		 * since it's possible to block while waiting for memory
2523		 * allocation.
2524		 */
2525		err = l2cap_segment_sdu(chan, &seg_queue, msg, len);
2526
2527		/* The channel could have been closed while segmenting,
2528		 * check that it is still connected.
2529		 */
2530		if (chan->state != BT_CONNECTED) {
2531			__skb_queue_purge(&seg_queue);
2532			err = -ENOTCONN;
2533		}
2534
2535		if (err)
2536			break;
2537
2538		if (chan->mode == L2CAP_MODE_ERTM)
2539			l2cap_tx(chan, NULL, &seg_queue, L2CAP_EV_DATA_REQUEST);
2540		else
2541			l2cap_streaming_send(chan, &seg_queue);
2542
2543		err = len;
2544
2545		/* If the skbs were not queued for sending, they'll still be in
2546		 * seg_queue and need to be purged.
2547		 */
2548		__skb_queue_purge(&seg_queue);
2549		break;
2550
2551	default:
2552		BT_DBG("bad state %1.1x", chan->mode);
2553		err = -EBADFD;
2554	}
2555
2556	return err;
2557}
2558EXPORT_SYMBOL_GPL(l2cap_chan_send);
2559
2560static void l2cap_send_srej(struct l2cap_chan *chan, u16 txseq)
2561{
2562	struct l2cap_ctrl control;
2563	u16 seq;
2564
2565	BT_DBG("chan %p, txseq %u", chan, txseq);
2566
2567	memset(&control, 0, sizeof(control));
2568	control.sframe = 1;
2569	control.super = L2CAP_SUPER_SREJ;
2570
2571	for (seq = chan->expected_tx_seq; seq != txseq;
2572	     seq = __next_seq(chan, seq)) {
2573		if (!l2cap_ertm_seq_in_queue(&chan->srej_q, seq)) {
2574			control.reqseq = seq;
2575			l2cap_send_sframe(chan, &control);
2576			l2cap_seq_list_append(&chan->srej_list, seq);
2577		}
2578	}
2579
2580	chan->expected_tx_seq = __next_seq(chan, txseq);
2581}
2582
2583static void l2cap_send_srej_tail(struct l2cap_chan *chan)
2584{
2585	struct l2cap_ctrl control;
2586
2587	BT_DBG("chan %p", chan);
2588
2589	if (chan->srej_list.tail == L2CAP_SEQ_LIST_CLEAR)
2590		return;
2591
2592	memset(&control, 0, sizeof(control));
2593	control.sframe = 1;
2594	control.super = L2CAP_SUPER_SREJ;
2595	control.reqseq = chan->srej_list.tail;
2596	l2cap_send_sframe(chan, &control);
2597}
2598
2599static void l2cap_send_srej_list(struct l2cap_chan *chan, u16 txseq)
2600{
2601	struct l2cap_ctrl control;
2602	u16 initial_head;
2603	u16 seq;
2604
2605	BT_DBG("chan %p, txseq %u", chan, txseq);
2606
2607	memset(&control, 0, sizeof(control));
2608	control.sframe = 1;
2609	control.super = L2CAP_SUPER_SREJ;
2610
2611	/* Capture initial list head to allow only one pass through the list. */
2612	initial_head = chan->srej_list.head;
2613
2614	do {
2615		seq = l2cap_seq_list_pop(&chan->srej_list);
2616		if (seq == txseq || seq == L2CAP_SEQ_LIST_CLEAR)
2617			break;
2618
2619		control.reqseq = seq;
2620		l2cap_send_sframe(chan, &control);
2621		l2cap_seq_list_append(&chan->srej_list, seq);
2622	} while (chan->srej_list.head != initial_head);
2623}
2624
2625static void l2cap_process_reqseq(struct l2cap_chan *chan, u16 reqseq)
2626{
2627	struct sk_buff *acked_skb;
2628	u16 ackseq;
2629
2630	BT_DBG("chan %p, reqseq %u", chan, reqseq);
2631
2632	if (chan->unacked_frames == 0 || reqseq == chan->expected_ack_seq)
2633		return;
2634
2635	BT_DBG("expected_ack_seq %u, unacked_frames %u",
2636	       chan->expected_ack_seq, chan->unacked_frames);
2637
2638	for (ackseq = chan->expected_ack_seq; ackseq != reqseq;
2639	     ackseq = __next_seq(chan, ackseq)) {
2640
2641		acked_skb = l2cap_ertm_seq_in_queue(&chan->tx_q, ackseq);
2642		if (acked_skb) {
2643			skb_unlink(acked_skb, &chan->tx_q);
2644			kfree_skb(acked_skb);
2645			chan->unacked_frames--;
2646		}
2647	}
2648
2649	chan->expected_ack_seq = reqseq;
2650
2651	if (chan->unacked_frames == 0)
2652		__clear_retrans_timer(chan);
2653
2654	BT_DBG("unacked_frames %u", chan->unacked_frames);
2655}
2656
2657static void l2cap_abort_rx_srej_sent(struct l2cap_chan *chan)
2658{
2659	BT_DBG("chan %p", chan);
2660
2661	chan->expected_tx_seq = chan->buffer_seq;
2662	l2cap_seq_list_clear(&chan->srej_list);
2663	skb_queue_purge(&chan->srej_q);
2664	chan->rx_state = L2CAP_RX_STATE_RECV;
2665}
2666
2667static void l2cap_tx_state_xmit(struct l2cap_chan *chan,
2668				struct l2cap_ctrl *control,
2669				struct sk_buff_head *skbs, u8 event)
2670{
2671	BT_DBG("chan %p, control %p, skbs %p, event %d", chan, control, skbs,
2672	       event);
2673
2674	switch (event) {
2675	case L2CAP_EV_DATA_REQUEST:
2676		if (chan->tx_send_head == NULL)
2677			chan->tx_send_head = skb_peek(skbs);
2678
2679		skb_queue_splice_tail_init(skbs, &chan->tx_q);
2680		l2cap_ertm_send(chan);
2681		break;
2682	case L2CAP_EV_LOCAL_BUSY_DETECTED:
2683		BT_DBG("Enter LOCAL_BUSY");
2684		set_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2685
2686		if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) {
2687			/* The SREJ_SENT state must be aborted if we are to
2688			 * enter the LOCAL_BUSY state.
2689			 */
2690			l2cap_abort_rx_srej_sent(chan);
2691		}
2692
2693		l2cap_send_ack(chan);
2694
2695		break;
2696	case L2CAP_EV_LOCAL_BUSY_CLEAR:
2697		BT_DBG("Exit LOCAL_BUSY");
2698		clear_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2699
2700		if (test_bit(CONN_RNR_SENT, &chan->conn_state)) {
2701			struct l2cap_ctrl local_control;
2702
2703			memset(&local_control, 0, sizeof(local_control));
2704			local_control.sframe = 1;
2705			local_control.super = L2CAP_SUPER_RR;
2706			local_control.poll = 1;
2707			local_control.reqseq = chan->buffer_seq;
2708			l2cap_send_sframe(chan, &local_control);
2709
2710			chan->retry_count = 1;
2711			__set_monitor_timer(chan);
2712			chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2713		}
2714		break;
2715	case L2CAP_EV_RECV_REQSEQ_AND_FBIT:
2716		l2cap_process_reqseq(chan, control->reqseq);
2717		break;
2718	case L2CAP_EV_EXPLICIT_POLL:
2719		l2cap_send_rr_or_rnr(chan, 1);
2720		chan->retry_count = 1;
2721		__set_monitor_timer(chan);
2722		__clear_ack_timer(chan);
2723		chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2724		break;
2725	case L2CAP_EV_RETRANS_TO:
2726		l2cap_send_rr_or_rnr(chan, 1);
2727		chan->retry_count = 1;
2728		__set_monitor_timer(chan);
2729		chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2730		break;
2731	case L2CAP_EV_RECV_FBIT:
2732		/* Nothing to process */
2733		break;
2734	default:
2735		break;
2736	}
2737}
2738
2739static void l2cap_tx_state_wait_f(struct l2cap_chan *chan,
2740				  struct l2cap_ctrl *control,
2741				  struct sk_buff_head *skbs, u8 event)
2742{
2743	BT_DBG("chan %p, control %p, skbs %p, event %d", chan, control, skbs,
2744	       event);
2745
2746	switch (event) {
2747	case L2CAP_EV_DATA_REQUEST:
2748		if (chan->tx_send_head == NULL)
2749			chan->tx_send_head = skb_peek(skbs);
2750		/* Queue data, but don't send. */
2751		skb_queue_splice_tail_init(skbs, &chan->tx_q);
2752		break;
2753	case L2CAP_EV_LOCAL_BUSY_DETECTED:
2754		BT_DBG("Enter LOCAL_BUSY");
2755		set_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2756
2757		if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) {
2758			/* The SREJ_SENT state must be aborted if we are to
2759			 * enter the LOCAL_BUSY state.
2760			 */
2761			l2cap_abort_rx_srej_sent(chan);
2762		}
2763
2764		l2cap_send_ack(chan);
2765
2766		break;
2767	case L2CAP_EV_LOCAL_BUSY_CLEAR:
2768		BT_DBG("Exit LOCAL_BUSY");
2769		clear_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2770
2771		if (test_bit(CONN_RNR_SENT, &chan->conn_state)) {
2772			struct l2cap_ctrl local_control;
2773			memset(&local_control, 0, sizeof(local_control));
2774			local_control.sframe = 1;
2775			local_control.super = L2CAP_SUPER_RR;
2776			local_control.poll = 1;
2777			local_control.reqseq = chan->buffer_seq;
2778			l2cap_send_sframe(chan, &local_control);
2779
2780			chan->retry_count = 1;
2781			__set_monitor_timer(chan);
2782			chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2783		}
2784		break;
2785	case L2CAP_EV_RECV_REQSEQ_AND_FBIT:
2786		l2cap_process_reqseq(chan, control->reqseq);
2787
2788		/* Fall through */
2789
2790	case L2CAP_EV_RECV_FBIT:
2791		if (control && control->final) {
2792			__clear_monitor_timer(chan);
2793			if (chan->unacked_frames > 0)
2794				__set_retrans_timer(chan);
2795			chan->retry_count = 0;
2796			chan->tx_state = L2CAP_TX_STATE_XMIT;
2797			BT_DBG("recv fbit tx_state 0x2.2%x", chan->tx_state);
2798		}
2799		break;
2800	case L2CAP_EV_EXPLICIT_POLL:
2801		/* Ignore */
2802		break;
2803	case L2CAP_EV_MONITOR_TO:
2804		if (chan->max_tx == 0 || chan->retry_count < chan->max_tx) {
2805			l2cap_send_rr_or_rnr(chan, 1);
2806			__set_monitor_timer(chan);
2807			chan->retry_count++;
2808		} else {
2809			l2cap_send_disconn_req(chan, ECONNABORTED);
2810		}
2811		break;
2812	default:
2813		break;
2814	}
2815}
2816
2817static void l2cap_tx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
2818		     struct sk_buff_head *skbs, u8 event)
2819{
2820	BT_DBG("chan %p, control %p, skbs %p, event %d, state %d",
2821	       chan, control, skbs, event, chan->tx_state);
2822
2823	switch (chan->tx_state) {
2824	case L2CAP_TX_STATE_XMIT:
2825		l2cap_tx_state_xmit(chan, control, skbs, event);
2826		break;
2827	case L2CAP_TX_STATE_WAIT_F:
2828		l2cap_tx_state_wait_f(chan, control, skbs, event);
2829		break;
2830	default:
2831		/* Ignore event */
2832		break;
2833	}
2834}
2835
2836static void l2cap_pass_to_tx(struct l2cap_chan *chan,
2837			     struct l2cap_ctrl *control)
2838{
2839	BT_DBG("chan %p, control %p", chan, control);
2840	l2cap_tx(chan, control, NULL, L2CAP_EV_RECV_REQSEQ_AND_FBIT);
2841}
2842
2843static void l2cap_pass_to_tx_fbit(struct l2cap_chan *chan,
2844				  struct l2cap_ctrl *control)
2845{
2846	BT_DBG("chan %p, control %p", chan, control);
2847	l2cap_tx(chan, control, NULL, L2CAP_EV_RECV_FBIT);
2848}
2849
2850/* Copy frame to all raw sockets on that connection */
2851static void l2cap_raw_recv(struct l2cap_conn *conn, struct sk_buff *skb)
2852{
2853	struct sk_buff *nskb;
2854	struct l2cap_chan *chan;
2855
2856	BT_DBG("conn %p", conn);
2857
2858	mutex_lock(&conn->chan_lock);
2859
2860	list_for_each_entry(chan, &conn->chan_l, list) {
2861		if (chan->chan_type != L2CAP_CHAN_RAW)
2862			continue;
2863
2864		/* Don't send frame to the channel it came from */
2865		if (bt_cb(skb)->l2cap.chan == chan)
2866			continue;
2867
2868		nskb = skb_clone(skb, GFP_KERNEL);
2869		if (!nskb)
2870			continue;
2871		if (chan->ops->recv(chan, nskb))
2872			kfree_skb(nskb);
2873	}
2874
2875	mutex_unlock(&conn->chan_lock);
2876}
2877
2878/* ---- L2CAP signalling commands ---- */
2879static struct sk_buff *l2cap_build_cmd(struct l2cap_conn *conn, u8 code,
2880				       u8 ident, u16 dlen, void *data)
2881{
2882	struct sk_buff *skb, **frag;
2883	struct l2cap_cmd_hdr *cmd;
2884	struct l2cap_hdr *lh;
2885	int len, count;
2886
2887	BT_DBG("conn %p, code 0x%2.2x, ident 0x%2.2x, len %u",
2888	       conn, code, ident, dlen);
2889
2890	if (conn->mtu < L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE)
2891		return NULL;
2892
2893	len = L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE + dlen;
2894	count = min_t(unsigned int, conn->mtu, len);
2895
2896	skb = bt_skb_alloc(count, GFP_KERNEL);
2897	if (!skb)
2898		return NULL;
2899
2900	lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
2901	lh->len = cpu_to_le16(L2CAP_CMD_HDR_SIZE + dlen);
2902
2903	if (conn->hcon->type == LE_LINK)
2904		lh->cid = cpu_to_le16(L2CAP_CID_LE_SIGNALING);
2905	else
2906		lh->cid = cpu_to_le16(L2CAP_CID_SIGNALING);
2907
2908	cmd = (struct l2cap_cmd_hdr *) skb_put(skb, L2CAP_CMD_HDR_SIZE);
2909	cmd->code  = code;
2910	cmd->ident = ident;
2911	cmd->len   = cpu_to_le16(dlen);
2912
2913	if (dlen) {
2914		count -= L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE;
2915		memcpy(skb_put(skb, count), data, count);
2916		data += count;
2917	}
2918
2919	len -= skb->len;
2920
2921	/* Continuation fragments (no L2CAP header) */
2922	frag = &skb_shinfo(skb)->frag_list;
2923	while (len) {
2924		count = min_t(unsigned int, conn->mtu, len);
2925
2926		*frag = bt_skb_alloc(count, GFP_KERNEL);
2927		if (!*frag)
2928			goto fail;
2929
2930		memcpy(skb_put(*frag, count), data, count);
2931
2932		len  -= count;
2933		data += count;
2934
2935		frag = &(*frag)->next;
2936	}
2937
2938	return skb;
2939
2940fail:
2941	kfree_skb(skb);
2942	return NULL;
2943}
2944
2945static inline int l2cap_get_conf_opt(void **ptr, int *type, int *olen,
2946				     unsigned long *val)
2947{
2948	struct l2cap_conf_opt *opt = *ptr;
2949	int len;
2950
2951	len = L2CAP_CONF_OPT_SIZE + opt->len;
2952	*ptr += len;
2953
2954	*type = opt->type;
2955	*olen = opt->len;
2956
2957	switch (opt->len) {
2958	case 1:
2959		*val = *((u8 *) opt->val);
2960		break;
2961
2962	case 2:
2963		*val = get_unaligned_le16(opt->val);
2964		break;
2965
2966	case 4:
2967		*val = get_unaligned_le32(opt->val);
2968		break;
2969
2970	default:
2971		*val = (unsigned long) opt->val;
2972		break;
2973	}
2974
2975	BT_DBG("type 0x%2.2x len %u val 0x%lx", *type, opt->len, *val);
2976	return len;
2977}
2978
2979static void l2cap_add_conf_opt(void **ptr, u8 type, u8 len, unsigned long val)
2980{
2981	struct l2cap_conf_opt *opt = *ptr;
2982
2983	BT_DBG("type 0x%2.2x len %u val 0x%lx", type, len, val);
2984
 
 
 
2985	opt->type = type;
2986	opt->len  = len;
2987
2988	switch (len) {
2989	case 1:
2990		*((u8 *) opt->val)  = val;
2991		break;
2992
2993	case 2:
2994		put_unaligned_le16(val, opt->val);
2995		break;
2996
2997	case 4:
2998		put_unaligned_le32(val, opt->val);
2999		break;
3000
3001	default:
3002		memcpy(opt->val, (void *) val, len);
3003		break;
3004	}
3005
3006	*ptr += L2CAP_CONF_OPT_SIZE + len;
3007}
3008
3009static void l2cap_add_opt_efs(void **ptr, struct l2cap_chan *chan)
3010{
3011	struct l2cap_conf_efs efs;
3012
3013	switch (chan->mode) {
3014	case L2CAP_MODE_ERTM:
3015		efs.id		= chan->local_id;
3016		efs.stype	= chan->local_stype;
3017		efs.msdu	= cpu_to_le16(chan->local_msdu);
3018		efs.sdu_itime	= cpu_to_le32(chan->local_sdu_itime);
3019		efs.acc_lat	= cpu_to_le32(L2CAP_DEFAULT_ACC_LAT);
3020		efs.flush_to	= cpu_to_le32(L2CAP_EFS_DEFAULT_FLUSH_TO);
3021		break;
3022
3023	case L2CAP_MODE_STREAMING:
3024		efs.id		= 1;
3025		efs.stype	= L2CAP_SERV_BESTEFFORT;
3026		efs.msdu	= cpu_to_le16(chan->local_msdu);
3027		efs.sdu_itime	= cpu_to_le32(chan->local_sdu_itime);
3028		efs.acc_lat	= 0;
3029		efs.flush_to	= 0;
3030		break;
3031
3032	default:
3033		return;
3034	}
3035
3036	l2cap_add_conf_opt(ptr, L2CAP_CONF_EFS, sizeof(efs),
3037			   (unsigned long) &efs);
3038}
3039
3040static void l2cap_ack_timeout(struct work_struct *work)
3041{
3042	struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
3043					       ack_timer.work);
3044	u16 frames_to_ack;
3045
3046	BT_DBG("chan %p", chan);
3047
3048	l2cap_chan_lock(chan);
3049
3050	frames_to_ack = __seq_offset(chan, chan->buffer_seq,
3051				     chan->last_acked_seq);
3052
3053	if (frames_to_ack)
3054		l2cap_send_rr_or_rnr(chan, 0);
3055
3056	l2cap_chan_unlock(chan);
3057	l2cap_chan_put(chan);
3058}
3059
3060int l2cap_ertm_init(struct l2cap_chan *chan)
3061{
3062	int err;
3063
3064	chan->next_tx_seq = 0;
3065	chan->expected_tx_seq = 0;
3066	chan->expected_ack_seq = 0;
3067	chan->unacked_frames = 0;
3068	chan->buffer_seq = 0;
3069	chan->frames_sent = 0;
3070	chan->last_acked_seq = 0;
3071	chan->sdu = NULL;
3072	chan->sdu_last_frag = NULL;
3073	chan->sdu_len = 0;
3074
3075	skb_queue_head_init(&chan->tx_q);
3076
3077	chan->local_amp_id = AMP_ID_BREDR;
3078	chan->move_id = AMP_ID_BREDR;
3079	chan->move_state = L2CAP_MOVE_STABLE;
3080	chan->move_role = L2CAP_MOVE_ROLE_NONE;
3081
3082	if (chan->mode != L2CAP_MODE_ERTM)
3083		return 0;
3084
3085	chan->rx_state = L2CAP_RX_STATE_RECV;
3086	chan->tx_state = L2CAP_TX_STATE_XMIT;
3087
3088	INIT_DELAYED_WORK(&chan->retrans_timer, l2cap_retrans_timeout);
3089	INIT_DELAYED_WORK(&chan->monitor_timer, l2cap_monitor_timeout);
3090	INIT_DELAYED_WORK(&chan->ack_timer, l2cap_ack_timeout);
3091
3092	skb_queue_head_init(&chan->srej_q);
3093
3094	err = l2cap_seq_list_init(&chan->srej_list, chan->tx_win);
3095	if (err < 0)
3096		return err;
3097
3098	err = l2cap_seq_list_init(&chan->retrans_list, chan->remote_tx_win);
3099	if (err < 0)
3100		l2cap_seq_list_free(&chan->srej_list);
3101
3102	return err;
3103}
3104
3105static inline __u8 l2cap_select_mode(__u8 mode, __u16 remote_feat_mask)
3106{
3107	switch (mode) {
3108	case L2CAP_MODE_STREAMING:
3109	case L2CAP_MODE_ERTM:
3110		if (l2cap_mode_supported(mode, remote_feat_mask))
3111			return mode;
3112		/* fall through */
3113	default:
3114		return L2CAP_MODE_BASIC;
3115	}
3116}
3117
3118static inline bool __l2cap_ews_supported(struct l2cap_conn *conn)
3119{
3120	return ((conn->local_fixed_chan & L2CAP_FC_A2MP) &&
3121		(conn->feat_mask & L2CAP_FEAT_EXT_WINDOW));
3122}
3123
3124static inline bool __l2cap_efs_supported(struct l2cap_conn *conn)
3125{
3126	return ((conn->local_fixed_chan & L2CAP_FC_A2MP) &&
3127		(conn->feat_mask & L2CAP_FEAT_EXT_FLOW));
3128}
3129
3130static void __l2cap_set_ertm_timeouts(struct l2cap_chan *chan,
3131				      struct l2cap_conf_rfc *rfc)
3132{
3133	if (chan->local_amp_id != AMP_ID_BREDR && chan->hs_hcon) {
3134		u64 ertm_to = chan->hs_hcon->hdev->amp_be_flush_to;
3135
3136		/* Class 1 devices have must have ERTM timeouts
3137		 * exceeding the Link Supervision Timeout.  The
3138		 * default Link Supervision Timeout for AMP
3139		 * controllers is 10 seconds.
3140		 *
3141		 * Class 1 devices use 0xffffffff for their
3142		 * best-effort flush timeout, so the clamping logic
3143		 * will result in a timeout that meets the above
3144		 * requirement.  ERTM timeouts are 16-bit values, so
3145		 * the maximum timeout is 65.535 seconds.
3146		 */
3147
3148		/* Convert timeout to milliseconds and round */
3149		ertm_to = DIV_ROUND_UP_ULL(ertm_to, 1000);
3150
3151		/* This is the recommended formula for class 2 devices
3152		 * that start ERTM timers when packets are sent to the
3153		 * controller.
3154		 */
3155		ertm_to = 3 * ertm_to + 500;
3156
3157		if (ertm_to > 0xffff)
3158			ertm_to = 0xffff;
3159
3160		rfc->retrans_timeout = cpu_to_le16((u16) ertm_to);
3161		rfc->monitor_timeout = rfc->retrans_timeout;
3162	} else {
3163		rfc->retrans_timeout = cpu_to_le16(L2CAP_DEFAULT_RETRANS_TO);
3164		rfc->monitor_timeout = cpu_to_le16(L2CAP_DEFAULT_MONITOR_TO);
3165	}
3166}
3167
3168static inline void l2cap_txwin_setup(struct l2cap_chan *chan)
3169{
3170	if (chan->tx_win > L2CAP_DEFAULT_TX_WINDOW &&
3171	    __l2cap_ews_supported(chan->conn)) {
3172		/* use extended control field */
3173		set_bit(FLAG_EXT_CTRL, &chan->flags);
3174		chan->tx_win_max = L2CAP_DEFAULT_EXT_WINDOW;
3175	} else {
3176		chan->tx_win = min_t(u16, chan->tx_win,
3177				     L2CAP_DEFAULT_TX_WINDOW);
3178		chan->tx_win_max = L2CAP_DEFAULT_TX_WINDOW;
3179	}
3180	chan->ack_win = chan->tx_win;
3181}
3182
3183static int l2cap_build_conf_req(struct l2cap_chan *chan, void *data)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3184{
3185	struct l2cap_conf_req *req = data;
3186	struct l2cap_conf_rfc rfc = { .mode = chan->mode };
3187	void *ptr = req->data;
 
3188	u16 size;
3189
3190	BT_DBG("chan %p", chan);
3191
3192	if (chan->num_conf_req || chan->num_conf_rsp)
3193		goto done;
3194
3195	switch (chan->mode) {
3196	case L2CAP_MODE_STREAMING:
3197	case L2CAP_MODE_ERTM:
3198		if (test_bit(CONF_STATE2_DEVICE, &chan->conf_state))
3199			break;
3200
3201		if (__l2cap_efs_supported(chan->conn))
3202			set_bit(FLAG_EFS_ENABLE, &chan->flags);
3203
3204		/* fall through */
3205	default:
3206		chan->mode = l2cap_select_mode(rfc.mode, chan->conn->feat_mask);
3207		break;
3208	}
3209
3210done:
3211	if (chan->imtu != L2CAP_DEFAULT_MTU)
3212		l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->imtu);
 
 
 
 
3213
3214	switch (chan->mode) {
3215	case L2CAP_MODE_BASIC:
3216		if (disable_ertm)
3217			break;
3218
3219		if (!(chan->conn->feat_mask & L2CAP_FEAT_ERTM) &&
3220		    !(chan->conn->feat_mask & L2CAP_FEAT_STREAMING))
3221			break;
3222
3223		rfc.mode            = L2CAP_MODE_BASIC;
3224		rfc.txwin_size      = 0;
3225		rfc.max_transmit    = 0;
3226		rfc.retrans_timeout = 0;
3227		rfc.monitor_timeout = 0;
3228		rfc.max_pdu_size    = 0;
3229
3230		l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3231				   (unsigned long) &rfc);
3232		break;
3233
3234	case L2CAP_MODE_ERTM:
3235		rfc.mode            = L2CAP_MODE_ERTM;
3236		rfc.max_transmit    = chan->max_tx;
3237
3238		__l2cap_set_ertm_timeouts(chan, &rfc);
3239
3240		size = min_t(u16, L2CAP_DEFAULT_MAX_PDU_SIZE, chan->conn->mtu -
3241			     L2CAP_EXT_HDR_SIZE - L2CAP_SDULEN_SIZE -
3242			     L2CAP_FCS_SIZE);
3243		rfc.max_pdu_size = cpu_to_le16(size);
3244
3245		l2cap_txwin_setup(chan);
3246
3247		rfc.txwin_size = min_t(u16, chan->tx_win,
3248				       L2CAP_DEFAULT_TX_WINDOW);
3249
3250		l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3251				   (unsigned long) &rfc);
3252
3253		if (test_bit(FLAG_EFS_ENABLE, &chan->flags))
3254			l2cap_add_opt_efs(&ptr, chan);
3255
3256		if (test_bit(FLAG_EXT_CTRL, &chan->flags))
3257			l2cap_add_conf_opt(&ptr, L2CAP_CONF_EWS, 2,
3258					   chan->tx_win);
3259
3260		if (chan->conn->feat_mask & L2CAP_FEAT_FCS)
3261			if (chan->fcs == L2CAP_FCS_NONE ||
3262			    test_bit(CONF_RECV_NO_FCS, &chan->conf_state)) {
3263				chan->fcs = L2CAP_FCS_NONE;
3264				l2cap_add_conf_opt(&ptr, L2CAP_CONF_FCS, 1,
3265						   chan->fcs);
3266			}
3267		break;
3268
3269	case L2CAP_MODE_STREAMING:
3270		l2cap_txwin_setup(chan);
3271		rfc.mode            = L2CAP_MODE_STREAMING;
3272		rfc.txwin_size      = 0;
3273		rfc.max_transmit    = 0;
3274		rfc.retrans_timeout = 0;
3275		rfc.monitor_timeout = 0;
3276
3277		size = min_t(u16, L2CAP_DEFAULT_MAX_PDU_SIZE, chan->conn->mtu -
3278			     L2CAP_EXT_HDR_SIZE - L2CAP_SDULEN_SIZE -
3279			     L2CAP_FCS_SIZE);
3280		rfc.max_pdu_size = cpu_to_le16(size);
3281
3282		l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3283				   (unsigned long) &rfc);
3284
3285		if (test_bit(FLAG_EFS_ENABLE, &chan->flags))
3286			l2cap_add_opt_efs(&ptr, chan);
3287
3288		if (chan->conn->feat_mask & L2CAP_FEAT_FCS)
3289			if (chan->fcs == L2CAP_FCS_NONE ||
3290			    test_bit(CONF_RECV_NO_FCS, &chan->conf_state)) {
3291				chan->fcs = L2CAP_FCS_NONE;
3292				l2cap_add_conf_opt(&ptr, L2CAP_CONF_FCS, 1,
3293						   chan->fcs);
3294			}
3295		break;
3296	}
3297
3298	req->dcid  = cpu_to_le16(chan->dcid);
3299	req->flags = cpu_to_le16(0);
3300
3301	return ptr - data;
3302}
3303
3304static int l2cap_parse_conf_req(struct l2cap_chan *chan, void *data)
3305{
3306	struct l2cap_conf_rsp *rsp = data;
3307	void *ptr = rsp->data;
 
3308	void *req = chan->conf_req;
3309	int len = chan->conf_len;
3310	int type, hint, olen;
3311	unsigned long val;
3312	struct l2cap_conf_rfc rfc = { .mode = L2CAP_MODE_BASIC };
3313	struct l2cap_conf_efs efs;
3314	u8 remote_efs = 0;
3315	u16 mtu = L2CAP_DEFAULT_MTU;
3316	u16 result = L2CAP_CONF_SUCCESS;
3317	u16 size;
3318
3319	BT_DBG("chan %p", chan);
3320
3321	while (len >= L2CAP_CONF_OPT_SIZE) {
3322		len -= l2cap_get_conf_opt(&req, &type, &olen, &val);
 
 
3323
3324		hint  = type & L2CAP_CONF_HINT;
3325		type &= L2CAP_CONF_MASK;
3326
3327		switch (type) {
3328		case L2CAP_CONF_MTU:
 
 
3329			mtu = val;
3330			break;
3331
3332		case L2CAP_CONF_FLUSH_TO:
 
 
3333			chan->flush_to = val;
3334			break;
3335
3336		case L2CAP_CONF_QOS:
3337			break;
3338
3339		case L2CAP_CONF_RFC:
3340			if (olen == sizeof(rfc))
3341				memcpy(&rfc, (void *) val, olen);
 
3342			break;
3343
3344		case L2CAP_CONF_FCS:
 
 
3345			if (val == L2CAP_FCS_NONE)
3346				set_bit(CONF_RECV_NO_FCS, &chan->conf_state);
3347			break;
3348
3349		case L2CAP_CONF_EFS:
 
 
3350			remote_efs = 1;
3351			if (olen == sizeof(efs))
3352				memcpy(&efs, (void *) val, olen);
3353			break;
3354
3355		case L2CAP_CONF_EWS:
 
 
3356			if (!(chan->conn->local_fixed_chan & L2CAP_FC_A2MP))
3357				return -ECONNREFUSED;
3358
3359			set_bit(FLAG_EXT_CTRL, &chan->flags);
3360			set_bit(CONF_EWS_RECV, &chan->conf_state);
3361			chan->tx_win_max = L2CAP_DEFAULT_EXT_WINDOW;
3362			chan->remote_tx_win = val;
3363			break;
3364
3365		default:
3366			if (hint)
3367				break;
3368
3369			result = L2CAP_CONF_UNKNOWN;
3370			*((u8 *) ptr++) = type;
3371			break;
3372		}
3373	}
3374
3375	if (chan->num_conf_rsp || chan->num_conf_req > 1)
3376		goto done;
3377
3378	switch (chan->mode) {
3379	case L2CAP_MODE_STREAMING:
3380	case L2CAP_MODE_ERTM:
3381		if (!test_bit(CONF_STATE2_DEVICE, &chan->conf_state)) {
3382			chan->mode = l2cap_select_mode(rfc.mode,
3383						       chan->conn->feat_mask);
3384			break;
3385		}
3386
3387		if (remote_efs) {
3388			if (__l2cap_efs_supported(chan->conn))
3389				set_bit(FLAG_EFS_ENABLE, &chan->flags);
3390			else
3391				return -ECONNREFUSED;
3392		}
3393
3394		if (chan->mode != rfc.mode)
3395			return -ECONNREFUSED;
3396
3397		break;
3398	}
3399
3400done:
3401	if (chan->mode != rfc.mode) {
3402		result = L2CAP_CONF_UNACCEPT;
3403		rfc.mode = chan->mode;
3404
3405		if (chan->num_conf_rsp == 1)
3406			return -ECONNREFUSED;
3407
3408		l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3409				   (unsigned long) &rfc);
3410	}
3411
3412	if (result == L2CAP_CONF_SUCCESS) {
3413		/* Configure output options and let the other side know
3414		 * which ones we don't like. */
3415
3416		if (mtu < L2CAP_DEFAULT_MIN_MTU)
3417			result = L2CAP_CONF_UNACCEPT;
3418		else {
3419			chan->omtu = mtu;
3420			set_bit(CONF_MTU_DONE, &chan->conf_state);
3421		}
3422		l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->omtu);
3423
3424		if (remote_efs) {
3425			if (chan->local_stype != L2CAP_SERV_NOTRAFIC &&
3426			    efs.stype != L2CAP_SERV_NOTRAFIC &&
3427			    efs.stype != chan->local_stype) {
3428
3429				result = L2CAP_CONF_UNACCEPT;
3430
3431				if (chan->num_conf_req >= 1)
3432					return -ECONNREFUSED;
3433
3434				l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS,
3435						   sizeof(efs),
3436						   (unsigned long) &efs);
3437			} else {
3438				/* Send PENDING Conf Rsp */
3439				result = L2CAP_CONF_PENDING;
3440				set_bit(CONF_LOC_CONF_PEND, &chan->conf_state);
3441			}
3442		}
3443
3444		switch (rfc.mode) {
3445		case L2CAP_MODE_BASIC:
3446			chan->fcs = L2CAP_FCS_NONE;
3447			set_bit(CONF_MODE_DONE, &chan->conf_state);
3448			break;
3449
3450		case L2CAP_MODE_ERTM:
3451			if (!test_bit(CONF_EWS_RECV, &chan->conf_state))
3452				chan->remote_tx_win = rfc.txwin_size;
3453			else
3454				rfc.txwin_size = L2CAP_DEFAULT_TX_WINDOW;
3455
3456			chan->remote_max_tx = rfc.max_transmit;
3457
3458			size = min_t(u16, le16_to_cpu(rfc.max_pdu_size),
3459				     chan->conn->mtu - L2CAP_EXT_HDR_SIZE -
3460				     L2CAP_SDULEN_SIZE - L2CAP_FCS_SIZE);
3461			rfc.max_pdu_size = cpu_to_le16(size);
3462			chan->remote_mps = size;
3463
3464			__l2cap_set_ertm_timeouts(chan, &rfc);
3465
3466			set_bit(CONF_MODE_DONE, &chan->conf_state);
3467
3468			l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC,
3469					   sizeof(rfc), (unsigned long) &rfc);
3470
3471			if (test_bit(FLAG_EFS_ENABLE, &chan->flags)) {
3472				chan->remote_id = efs.id;
3473				chan->remote_stype = efs.stype;
3474				chan->remote_msdu = le16_to_cpu(efs.msdu);
3475				chan->remote_flush_to =
3476					le32_to_cpu(efs.flush_to);
3477				chan->remote_acc_lat =
3478					le32_to_cpu(efs.acc_lat);
3479				chan->remote_sdu_itime =
3480					le32_to_cpu(efs.sdu_itime);
3481				l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS,
3482						   sizeof(efs),
3483						   (unsigned long) &efs);
3484			}
3485			break;
3486
3487		case L2CAP_MODE_STREAMING:
3488			size = min_t(u16, le16_to_cpu(rfc.max_pdu_size),
3489				     chan->conn->mtu - L2CAP_EXT_HDR_SIZE -
3490				     L2CAP_SDULEN_SIZE - L2CAP_FCS_SIZE);
3491			rfc.max_pdu_size = cpu_to_le16(size);
3492			chan->remote_mps = size;
3493
3494			set_bit(CONF_MODE_DONE, &chan->conf_state);
3495
3496			l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3497					   (unsigned long) &rfc);
3498
3499			break;
3500
3501		default:
3502			result = L2CAP_CONF_UNACCEPT;
3503
3504			memset(&rfc, 0, sizeof(rfc));
3505			rfc.mode = chan->mode;
3506		}
3507
3508		if (result == L2CAP_CONF_SUCCESS)
3509			set_bit(CONF_OUTPUT_DONE, &chan->conf_state);
3510	}
3511	rsp->scid   = cpu_to_le16(chan->dcid);
3512	rsp->result = cpu_to_le16(result);
3513	rsp->flags  = cpu_to_le16(0);
3514
3515	return ptr - data;
3516}
3517
3518static int l2cap_parse_conf_rsp(struct l2cap_chan *chan, void *rsp, int len,
3519				void *data, u16 *result)
3520{
3521	struct l2cap_conf_req *req = data;
3522	void *ptr = req->data;
 
3523	int type, olen;
3524	unsigned long val;
3525	struct l2cap_conf_rfc rfc = { .mode = L2CAP_MODE_BASIC };
3526	struct l2cap_conf_efs efs;
3527
3528	BT_DBG("chan %p, rsp %p, len %d, req %p", chan, rsp, len, data);
3529
3530	while (len >= L2CAP_CONF_OPT_SIZE) {
3531		len -= l2cap_get_conf_opt(&rsp, &type, &olen, &val);
 
 
3532
3533		switch (type) {
3534		case L2CAP_CONF_MTU:
 
 
3535			if (val < L2CAP_DEFAULT_MIN_MTU) {
3536				*result = L2CAP_CONF_UNACCEPT;
3537				chan->imtu = L2CAP_DEFAULT_MIN_MTU;
3538			} else
3539				chan->imtu = val;
3540			l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->imtu);
 
3541			break;
3542
3543		case L2CAP_CONF_FLUSH_TO:
 
 
3544			chan->flush_to = val;
3545			l2cap_add_conf_opt(&ptr, L2CAP_CONF_FLUSH_TO,
3546					   2, chan->flush_to);
3547			break;
3548
3549		case L2CAP_CONF_RFC:
3550			if (olen == sizeof(rfc))
3551				memcpy(&rfc, (void *)val, olen);
3552
3553			if (test_bit(CONF_STATE2_DEVICE, &chan->conf_state) &&
3554			    rfc.mode != chan->mode)
3555				return -ECONNREFUSED;
3556
3557			chan->fcs = 0;
3558
3559			l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC,
3560					   sizeof(rfc), (unsigned long) &rfc);
3561			break;
3562
3563		case L2CAP_CONF_EWS:
 
 
3564			chan->ack_win = min_t(u16, val, chan->ack_win);
3565			l2cap_add_conf_opt(&ptr, L2CAP_CONF_EWS, 2,
3566					   chan->tx_win);
3567			break;
3568
3569		case L2CAP_CONF_EFS:
3570			if (olen == sizeof(efs))
3571				memcpy(&efs, (void *)val, olen);
3572
3573			if (chan->local_stype != L2CAP_SERV_NOTRAFIC &&
3574			    efs.stype != L2CAP_SERV_NOTRAFIC &&
3575			    efs.stype != chan->local_stype)
3576				return -ECONNREFUSED;
3577
3578			l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS, sizeof(efs),
3579					   (unsigned long) &efs);
3580			break;
3581
3582		case L2CAP_CONF_FCS:
 
 
3583			if (*result == L2CAP_CONF_PENDING)
3584				if (val == L2CAP_FCS_NONE)
3585					set_bit(CONF_RECV_NO_FCS,
3586						&chan->conf_state);
3587			break;
3588		}
3589	}
3590
3591	if (chan->mode == L2CAP_MODE_BASIC && chan->mode != rfc.mode)
3592		return -ECONNREFUSED;
3593
3594	chan->mode = rfc.mode;
3595
3596	if (*result == L2CAP_CONF_SUCCESS || *result == L2CAP_CONF_PENDING) {
3597		switch (rfc.mode) {
3598		case L2CAP_MODE_ERTM:
3599			chan->retrans_timeout = le16_to_cpu(rfc.retrans_timeout);
3600			chan->monitor_timeout = le16_to_cpu(rfc.monitor_timeout);
3601			chan->mps    = le16_to_cpu(rfc.max_pdu_size);
3602			if (!test_bit(FLAG_EXT_CTRL, &chan->flags))
3603				chan->ack_win = min_t(u16, chan->ack_win,
3604						      rfc.txwin_size);
3605
3606			if (test_bit(FLAG_EFS_ENABLE, &chan->flags)) {
3607				chan->local_msdu = le16_to_cpu(efs.msdu);
3608				chan->local_sdu_itime =
3609					le32_to_cpu(efs.sdu_itime);
3610				chan->local_acc_lat = le32_to_cpu(efs.acc_lat);
3611				chan->local_flush_to =
3612					le32_to_cpu(efs.flush_to);
3613			}
3614			break;
3615
3616		case L2CAP_MODE_STREAMING:
3617			chan->mps    = le16_to_cpu(rfc.max_pdu_size);
3618		}
3619	}
3620
3621	req->dcid   = cpu_to_le16(chan->dcid);
3622	req->flags  = cpu_to_le16(0);
3623
3624	return ptr - data;
3625}
3626
3627static int l2cap_build_conf_rsp(struct l2cap_chan *chan, void *data,
3628				u16 result, u16 flags)
3629{
3630	struct l2cap_conf_rsp *rsp = data;
3631	void *ptr = rsp->data;
3632
3633	BT_DBG("chan %p", chan);
3634
3635	rsp->scid   = cpu_to_le16(chan->dcid);
3636	rsp->result = cpu_to_le16(result);
3637	rsp->flags  = cpu_to_le16(flags);
3638
3639	return ptr - data;
3640}
3641
3642void __l2cap_le_connect_rsp_defer(struct l2cap_chan *chan)
3643{
3644	struct l2cap_le_conn_rsp rsp;
3645	struct l2cap_conn *conn = chan->conn;
3646
3647	BT_DBG("chan %p", chan);
3648
3649	rsp.dcid    = cpu_to_le16(chan->scid);
3650	rsp.mtu     = cpu_to_le16(chan->imtu);
3651	rsp.mps     = cpu_to_le16(chan->mps);
3652	rsp.credits = cpu_to_le16(chan->rx_credits);
3653	rsp.result  = cpu_to_le16(L2CAP_CR_SUCCESS);
3654
3655	l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CONN_RSP, sizeof(rsp),
3656		       &rsp);
3657}
3658
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3659void __l2cap_connect_rsp_defer(struct l2cap_chan *chan)
3660{
3661	struct l2cap_conn_rsp rsp;
3662	struct l2cap_conn *conn = chan->conn;
3663	u8 buf[128];
3664	u8 rsp_code;
3665
3666	rsp.scid   = cpu_to_le16(chan->dcid);
3667	rsp.dcid   = cpu_to_le16(chan->scid);
3668	rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
3669	rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
3670
3671	if (chan->hs_hcon)
3672		rsp_code = L2CAP_CREATE_CHAN_RSP;
3673	else
3674		rsp_code = L2CAP_CONN_RSP;
3675
3676	BT_DBG("chan %p rsp_code %u", chan, rsp_code);
3677
3678	l2cap_send_cmd(conn, chan->ident, rsp_code, sizeof(rsp), &rsp);
3679
3680	if (test_and_set_bit(CONF_REQ_SENT, &chan->conf_state))
3681		return;
3682
3683	l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
3684		       l2cap_build_conf_req(chan, buf), buf);
3685	chan->num_conf_req++;
3686}
3687
3688static void l2cap_conf_rfc_get(struct l2cap_chan *chan, void *rsp, int len)
3689{
3690	int type, olen;
3691	unsigned long val;
3692	/* Use sane default values in case a misbehaving remote device
3693	 * did not send an RFC or extended window size option.
3694	 */
3695	u16 txwin_ext = chan->ack_win;
3696	struct l2cap_conf_rfc rfc = {
3697		.mode = chan->mode,
3698		.retrans_timeout = cpu_to_le16(L2CAP_DEFAULT_RETRANS_TO),
3699		.monitor_timeout = cpu_to_le16(L2CAP_DEFAULT_MONITOR_TO),
3700		.max_pdu_size = cpu_to_le16(chan->imtu),
3701		.txwin_size = min_t(u16, chan->ack_win, L2CAP_DEFAULT_TX_WINDOW),
3702	};
3703
3704	BT_DBG("chan %p, rsp %p, len %d", chan, rsp, len);
3705
3706	if ((chan->mode != L2CAP_MODE_ERTM) && (chan->mode != L2CAP_MODE_STREAMING))
3707		return;
3708
3709	while (len >= L2CAP_CONF_OPT_SIZE) {
3710		len -= l2cap_get_conf_opt(&rsp, &type, &olen, &val);
 
 
3711
3712		switch (type) {
3713		case L2CAP_CONF_RFC:
3714			if (olen == sizeof(rfc))
3715				memcpy(&rfc, (void *)val, olen);
 
3716			break;
3717		case L2CAP_CONF_EWS:
 
 
3718			txwin_ext = val;
3719			break;
3720		}
3721	}
3722
3723	switch (rfc.mode) {
3724	case L2CAP_MODE_ERTM:
3725		chan->retrans_timeout = le16_to_cpu(rfc.retrans_timeout);
3726		chan->monitor_timeout = le16_to_cpu(rfc.monitor_timeout);
3727		chan->mps = le16_to_cpu(rfc.max_pdu_size);
3728		if (test_bit(FLAG_EXT_CTRL, &chan->flags))
3729			chan->ack_win = min_t(u16, chan->ack_win, txwin_ext);
3730		else
3731			chan->ack_win = min_t(u16, chan->ack_win,
3732					      rfc.txwin_size);
3733		break;
3734	case L2CAP_MODE_STREAMING:
3735		chan->mps    = le16_to_cpu(rfc.max_pdu_size);
3736	}
3737}
3738
3739static inline int l2cap_command_rej(struct l2cap_conn *conn,
3740				    struct l2cap_cmd_hdr *cmd, u16 cmd_len,
3741				    u8 *data)
3742{
3743	struct l2cap_cmd_rej_unk *rej = (struct l2cap_cmd_rej_unk *) data;
3744
3745	if (cmd_len < sizeof(*rej))
3746		return -EPROTO;
3747
3748	if (rej->reason != L2CAP_REJ_NOT_UNDERSTOOD)
3749		return 0;
3750
3751	if ((conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT) &&
3752	    cmd->ident == conn->info_ident) {
3753		cancel_delayed_work(&conn->info_timer);
3754
3755		conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
3756		conn->info_ident = 0;
3757
3758		l2cap_conn_start(conn);
3759	}
3760
3761	return 0;
3762}
3763
3764static struct l2cap_chan *l2cap_connect(struct l2cap_conn *conn,
3765					struct l2cap_cmd_hdr *cmd,
3766					u8 *data, u8 rsp_code, u8 amp_id)
3767{
3768	struct l2cap_conn_req *req = (struct l2cap_conn_req *) data;
3769	struct l2cap_conn_rsp rsp;
3770	struct l2cap_chan *chan = NULL, *pchan;
3771	int result, status = L2CAP_CS_NO_INFO;
3772
3773	u16 dcid = 0, scid = __le16_to_cpu(req->scid);
3774	__le16 psm = req->psm;
3775
3776	BT_DBG("psm 0x%2.2x scid 0x%4.4x", __le16_to_cpu(psm), scid);
3777
3778	/* Check if we have socket listening on psm */
3779	pchan = l2cap_global_chan_by_psm(BT_LISTEN, psm, &conn->hcon->src,
3780					 &conn->hcon->dst, ACL_LINK);
3781	if (!pchan) {
3782		result = L2CAP_CR_BAD_PSM;
3783		goto sendresp;
3784	}
3785
3786	mutex_lock(&conn->chan_lock);
3787	l2cap_chan_lock(pchan);
3788
3789	/* Check if the ACL is secure enough (if not SDP) */
3790	if (psm != cpu_to_le16(L2CAP_PSM_SDP) &&
3791	    !hci_conn_check_link_mode(conn->hcon)) {
3792		conn->disc_reason = HCI_ERROR_AUTH_FAILURE;
3793		result = L2CAP_CR_SEC_BLOCK;
3794		goto response;
3795	}
3796
3797	result = L2CAP_CR_NO_MEM;
3798
 
 
 
 
 
 
3799	/* Check if we already have channel with that dcid */
3800	if (__l2cap_get_chan_by_dcid(conn, scid))
 
3801		goto response;
 
3802
3803	chan = pchan->ops->new_connection(pchan);
3804	if (!chan)
3805		goto response;
3806
3807	/* For certain devices (ex: HID mouse), support for authentication,
3808	 * pairing and bonding is optional. For such devices, inorder to avoid
3809	 * the ACL alive for too long after L2CAP disconnection, reset the ACL
3810	 * disc_timeout back to HCI_DISCONN_TIMEOUT during L2CAP connect.
3811	 */
3812	conn->hcon->disc_timeout = HCI_DISCONN_TIMEOUT;
3813
3814	bacpy(&chan->src, &conn->hcon->src);
3815	bacpy(&chan->dst, &conn->hcon->dst);
3816	chan->src_type = bdaddr_src_type(conn->hcon);
3817	chan->dst_type = bdaddr_dst_type(conn->hcon);
3818	chan->psm  = psm;
3819	chan->dcid = scid;
3820	chan->local_amp_id = amp_id;
3821
3822	__l2cap_chan_add(conn, chan);
3823
3824	dcid = chan->scid;
3825
3826	__set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
3827
3828	chan->ident = cmd->ident;
3829
3830	if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE) {
3831		if (l2cap_chan_check_security(chan, false)) {
3832			if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
3833				l2cap_state_change(chan, BT_CONNECT2);
3834				result = L2CAP_CR_PEND;
3835				status = L2CAP_CS_AUTHOR_PEND;
3836				chan->ops->defer(chan);
3837			} else {
3838				/* Force pending result for AMP controllers.
3839				 * The connection will succeed after the
3840				 * physical link is up.
3841				 */
3842				if (amp_id == AMP_ID_BREDR) {
3843					l2cap_state_change(chan, BT_CONFIG);
3844					result = L2CAP_CR_SUCCESS;
3845				} else {
3846					l2cap_state_change(chan, BT_CONNECT2);
3847					result = L2CAP_CR_PEND;
3848				}
3849				status = L2CAP_CS_NO_INFO;
3850			}
3851		} else {
3852			l2cap_state_change(chan, BT_CONNECT2);
3853			result = L2CAP_CR_PEND;
3854			status = L2CAP_CS_AUTHEN_PEND;
3855		}
3856	} else {
3857		l2cap_state_change(chan, BT_CONNECT2);
3858		result = L2CAP_CR_PEND;
3859		status = L2CAP_CS_NO_INFO;
3860	}
3861
3862response:
3863	l2cap_chan_unlock(pchan);
3864	mutex_unlock(&conn->chan_lock);
3865	l2cap_chan_put(pchan);
3866
3867sendresp:
3868	rsp.scid   = cpu_to_le16(scid);
3869	rsp.dcid   = cpu_to_le16(dcid);
3870	rsp.result = cpu_to_le16(result);
3871	rsp.status = cpu_to_le16(status);
3872	l2cap_send_cmd(conn, cmd->ident, rsp_code, sizeof(rsp), &rsp);
3873
3874	if (result == L2CAP_CR_PEND && status == L2CAP_CS_NO_INFO) {
3875		struct l2cap_info_req info;
3876		info.type = cpu_to_le16(L2CAP_IT_FEAT_MASK);
3877
3878		conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_SENT;
3879		conn->info_ident = l2cap_get_ident(conn);
3880
3881		schedule_delayed_work(&conn->info_timer, L2CAP_INFO_TIMEOUT);
3882
3883		l2cap_send_cmd(conn, conn->info_ident, L2CAP_INFO_REQ,
3884			       sizeof(info), &info);
3885	}
3886
3887	if (chan && !test_bit(CONF_REQ_SENT, &chan->conf_state) &&
3888	    result == L2CAP_CR_SUCCESS) {
3889		u8 buf[128];
3890		set_bit(CONF_REQ_SENT, &chan->conf_state);
3891		l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
3892			       l2cap_build_conf_req(chan, buf), buf);
3893		chan->num_conf_req++;
3894	}
3895
3896	return chan;
3897}
3898
3899static int l2cap_connect_req(struct l2cap_conn *conn,
3900			     struct l2cap_cmd_hdr *cmd, u16 cmd_len, u8 *data)
3901{
3902	struct hci_dev *hdev = conn->hcon->hdev;
3903	struct hci_conn *hcon = conn->hcon;
3904
3905	if (cmd_len < sizeof(struct l2cap_conn_req))
3906		return -EPROTO;
3907
3908	hci_dev_lock(hdev);
3909	if (hci_dev_test_flag(hdev, HCI_MGMT) &&
3910	    !test_and_set_bit(HCI_CONN_MGMT_CONNECTED, &hcon->flags))
3911		mgmt_device_connected(hdev, hcon, 0, NULL, 0);
3912	hci_dev_unlock(hdev);
3913
3914	l2cap_connect(conn, cmd, data, L2CAP_CONN_RSP, 0);
3915	return 0;
3916}
3917
3918static int l2cap_connect_create_rsp(struct l2cap_conn *conn,
3919				    struct l2cap_cmd_hdr *cmd, u16 cmd_len,
3920				    u8 *data)
3921{
3922	struct l2cap_conn_rsp *rsp = (struct l2cap_conn_rsp *) data;
3923	u16 scid, dcid, result, status;
3924	struct l2cap_chan *chan;
3925	u8 req[128];
3926	int err;
3927
3928	if (cmd_len < sizeof(*rsp))
3929		return -EPROTO;
3930
3931	scid   = __le16_to_cpu(rsp->scid);
3932	dcid   = __le16_to_cpu(rsp->dcid);
3933	result = __le16_to_cpu(rsp->result);
3934	status = __le16_to_cpu(rsp->status);
3935
3936	BT_DBG("dcid 0x%4.4x scid 0x%4.4x result 0x%2.2x status 0x%2.2x",
3937	       dcid, scid, result, status);
3938
3939	mutex_lock(&conn->chan_lock);
3940
3941	if (scid) {
3942		chan = __l2cap_get_chan_by_scid(conn, scid);
3943		if (!chan) {
3944			err = -EBADSLT;
3945			goto unlock;
3946		}
3947	} else {
3948		chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
3949		if (!chan) {
3950			err = -EBADSLT;
3951			goto unlock;
3952		}
3953	}
3954
3955	err = 0;
3956
3957	l2cap_chan_lock(chan);
3958
3959	switch (result) {
3960	case L2CAP_CR_SUCCESS:
3961		l2cap_state_change(chan, BT_CONFIG);
3962		chan->ident = 0;
3963		chan->dcid = dcid;
3964		clear_bit(CONF_CONNECT_PEND, &chan->conf_state);
3965
3966		if (test_and_set_bit(CONF_REQ_SENT, &chan->conf_state))
3967			break;
3968
3969		l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
3970			       l2cap_build_conf_req(chan, req), req);
3971		chan->num_conf_req++;
3972		break;
3973
3974	case L2CAP_CR_PEND:
3975		set_bit(CONF_CONNECT_PEND, &chan->conf_state);
3976		break;
3977
3978	default:
3979		l2cap_chan_del(chan, ECONNREFUSED);
3980		break;
3981	}
3982
3983	l2cap_chan_unlock(chan);
3984
3985unlock:
3986	mutex_unlock(&conn->chan_lock);
3987
3988	return err;
3989}
3990
3991static inline void set_default_fcs(struct l2cap_chan *chan)
3992{
3993	/* FCS is enabled only in ERTM or streaming mode, if one or both
3994	 * sides request it.
3995	 */
3996	if (chan->mode != L2CAP_MODE_ERTM && chan->mode != L2CAP_MODE_STREAMING)
3997		chan->fcs = L2CAP_FCS_NONE;
3998	else if (!test_bit(CONF_RECV_NO_FCS, &chan->conf_state))
3999		chan->fcs = L2CAP_FCS_CRC16;
4000}
4001
4002static void l2cap_send_efs_conf_rsp(struct l2cap_chan *chan, void *data,
4003				    u8 ident, u16 flags)
4004{
4005	struct l2cap_conn *conn = chan->conn;
4006
4007	BT_DBG("conn %p chan %p ident %d flags 0x%4.4x", conn, chan, ident,
4008	       flags);
4009
4010	clear_bit(CONF_LOC_CONF_PEND, &chan->conf_state);
4011	set_bit(CONF_OUTPUT_DONE, &chan->conf_state);
4012
4013	l2cap_send_cmd(conn, ident, L2CAP_CONF_RSP,
4014		       l2cap_build_conf_rsp(chan, data,
4015					    L2CAP_CONF_SUCCESS, flags), data);
4016}
4017
4018static void cmd_reject_invalid_cid(struct l2cap_conn *conn, u8 ident,
4019				   u16 scid, u16 dcid)
4020{
4021	struct l2cap_cmd_rej_cid rej;
4022
4023	rej.reason = cpu_to_le16(L2CAP_REJ_INVALID_CID);
4024	rej.scid = __cpu_to_le16(scid);
4025	rej.dcid = __cpu_to_le16(dcid);
4026
4027	l2cap_send_cmd(conn, ident, L2CAP_COMMAND_REJ, sizeof(rej), &rej);
4028}
4029
4030static inline int l2cap_config_req(struct l2cap_conn *conn,
4031				   struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4032				   u8 *data)
4033{
4034	struct l2cap_conf_req *req = (struct l2cap_conf_req *) data;
4035	u16 dcid, flags;
4036	u8 rsp[64];
4037	struct l2cap_chan *chan;
4038	int len, err = 0;
4039
4040	if (cmd_len < sizeof(*req))
4041		return -EPROTO;
4042
4043	dcid  = __le16_to_cpu(req->dcid);
4044	flags = __le16_to_cpu(req->flags);
4045
4046	BT_DBG("dcid 0x%4.4x flags 0x%2.2x", dcid, flags);
4047
4048	chan = l2cap_get_chan_by_scid(conn, dcid);
4049	if (!chan) {
4050		cmd_reject_invalid_cid(conn, cmd->ident, dcid, 0);
4051		return 0;
4052	}
4053
4054	if (chan->state != BT_CONFIG && chan->state != BT_CONNECT2) {
 
4055		cmd_reject_invalid_cid(conn, cmd->ident, chan->scid,
4056				       chan->dcid);
4057		goto unlock;
4058	}
4059
4060	/* Reject if config buffer is too small. */
4061	len = cmd_len - sizeof(*req);
4062	if (chan->conf_len + len > sizeof(chan->conf_req)) {
4063		l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP,
4064			       l2cap_build_conf_rsp(chan, rsp,
4065			       L2CAP_CONF_REJECT, flags), rsp);
4066		goto unlock;
4067	}
4068
4069	/* Store config. */
4070	memcpy(chan->conf_req + chan->conf_len, req->data, len);
4071	chan->conf_len += len;
4072
4073	if (flags & L2CAP_CONF_FLAG_CONTINUATION) {
4074		/* Incomplete config. Send empty response. */
4075		l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP,
4076			       l2cap_build_conf_rsp(chan, rsp,
4077			       L2CAP_CONF_SUCCESS, flags), rsp);
4078		goto unlock;
4079	}
4080
4081	/* Complete config. */
4082	len = l2cap_parse_conf_req(chan, rsp);
4083	if (len < 0) {
4084		l2cap_send_disconn_req(chan, ECONNRESET);
4085		goto unlock;
4086	}
4087
4088	chan->ident = cmd->ident;
4089	l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP, len, rsp);
4090	chan->num_conf_rsp++;
4091
4092	/* Reset config buffer. */
4093	chan->conf_len = 0;
4094
4095	if (!test_bit(CONF_OUTPUT_DONE, &chan->conf_state))
4096		goto unlock;
4097
4098	if (test_bit(CONF_INPUT_DONE, &chan->conf_state)) {
4099		set_default_fcs(chan);
4100
4101		if (chan->mode == L2CAP_MODE_ERTM ||
4102		    chan->mode == L2CAP_MODE_STREAMING)
4103			err = l2cap_ertm_init(chan);
4104
4105		if (err < 0)
4106			l2cap_send_disconn_req(chan, -err);
4107		else
4108			l2cap_chan_ready(chan);
4109
4110		goto unlock;
4111	}
4112
4113	if (!test_and_set_bit(CONF_REQ_SENT, &chan->conf_state)) {
4114		u8 buf[64];
4115		l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
4116			       l2cap_build_conf_req(chan, buf), buf);
4117		chan->num_conf_req++;
4118	}
4119
4120	/* Got Conf Rsp PENDING from remote side and assume we sent
4121	   Conf Rsp PENDING in the code above */
4122	if (test_bit(CONF_REM_CONF_PEND, &chan->conf_state) &&
4123	    test_bit(CONF_LOC_CONF_PEND, &chan->conf_state)) {
4124
4125		/* check compatibility */
4126
4127		/* Send rsp for BR/EDR channel */
4128		if (!chan->hs_hcon)
4129			l2cap_send_efs_conf_rsp(chan, rsp, cmd->ident, flags);
4130		else
4131			chan->ident = cmd->ident;
4132	}
4133
4134unlock:
4135	l2cap_chan_unlock(chan);
4136	return err;
4137}
4138
4139static inline int l2cap_config_rsp(struct l2cap_conn *conn,
4140				   struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4141				   u8 *data)
4142{
4143	struct l2cap_conf_rsp *rsp = (struct l2cap_conf_rsp *)data;
4144	u16 scid, flags, result;
4145	struct l2cap_chan *chan;
4146	int len = cmd_len - sizeof(*rsp);
4147	int err = 0;
4148
4149	if (cmd_len < sizeof(*rsp))
4150		return -EPROTO;
4151
4152	scid   = __le16_to_cpu(rsp->scid);
4153	flags  = __le16_to_cpu(rsp->flags);
4154	result = __le16_to_cpu(rsp->result);
4155
4156	BT_DBG("scid 0x%4.4x flags 0x%2.2x result 0x%2.2x len %d", scid, flags,
4157	       result, len);
4158
4159	chan = l2cap_get_chan_by_scid(conn, scid);
4160	if (!chan)
4161		return 0;
4162
4163	switch (result) {
4164	case L2CAP_CONF_SUCCESS:
4165		l2cap_conf_rfc_get(chan, rsp->data, len);
4166		clear_bit(CONF_REM_CONF_PEND, &chan->conf_state);
4167		break;
4168
4169	case L2CAP_CONF_PENDING:
4170		set_bit(CONF_REM_CONF_PEND, &chan->conf_state);
4171
4172		if (test_bit(CONF_LOC_CONF_PEND, &chan->conf_state)) {
4173			char buf[64];
4174
4175			len = l2cap_parse_conf_rsp(chan, rsp->data, len,
4176						   buf, &result);
4177			if (len < 0) {
4178				l2cap_send_disconn_req(chan, ECONNRESET);
4179				goto done;
4180			}
4181
4182			if (!chan->hs_hcon) {
4183				l2cap_send_efs_conf_rsp(chan, buf, cmd->ident,
4184							0);
4185			} else {
4186				if (l2cap_check_efs(chan)) {
4187					amp_create_logical_link(chan);
4188					chan->ident = cmd->ident;
4189				}
4190			}
4191		}
4192		goto done;
4193
 
4194	case L2CAP_CONF_UNACCEPT:
4195		if (chan->num_conf_rsp <= L2CAP_CONF_MAX_CONF_RSP) {
4196			char req[64];
4197
4198			if (len > sizeof(req) - sizeof(struct l2cap_conf_req)) {
4199				l2cap_send_disconn_req(chan, ECONNRESET);
4200				goto done;
4201			}
4202
4203			/* throw out any old stored conf requests */
4204			result = L2CAP_CONF_SUCCESS;
4205			len = l2cap_parse_conf_rsp(chan, rsp->data, len,
4206						   req, &result);
4207			if (len < 0) {
4208				l2cap_send_disconn_req(chan, ECONNRESET);
4209				goto done;
4210			}
4211
4212			l2cap_send_cmd(conn, l2cap_get_ident(conn),
4213				       L2CAP_CONF_REQ, len, req);
4214			chan->num_conf_req++;
4215			if (result != L2CAP_CONF_SUCCESS)
4216				goto done;
4217			break;
4218		}
 
4219
4220	default:
4221		l2cap_chan_set_err(chan, ECONNRESET);
4222
4223		__set_chan_timer(chan, L2CAP_DISC_REJ_TIMEOUT);
4224		l2cap_send_disconn_req(chan, ECONNRESET);
4225		goto done;
4226	}
4227
4228	if (flags & L2CAP_CONF_FLAG_CONTINUATION)
4229		goto done;
4230
4231	set_bit(CONF_INPUT_DONE, &chan->conf_state);
4232
4233	if (test_bit(CONF_OUTPUT_DONE, &chan->conf_state)) {
4234		set_default_fcs(chan);
4235
4236		if (chan->mode == L2CAP_MODE_ERTM ||
4237		    chan->mode == L2CAP_MODE_STREAMING)
4238			err = l2cap_ertm_init(chan);
4239
4240		if (err < 0)
4241			l2cap_send_disconn_req(chan, -err);
4242		else
4243			l2cap_chan_ready(chan);
4244	}
4245
4246done:
4247	l2cap_chan_unlock(chan);
4248	return err;
4249}
4250
4251static inline int l2cap_disconnect_req(struct l2cap_conn *conn,
4252				       struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4253				       u8 *data)
4254{
4255	struct l2cap_disconn_req *req = (struct l2cap_disconn_req *) data;
4256	struct l2cap_disconn_rsp rsp;
4257	u16 dcid, scid;
4258	struct l2cap_chan *chan;
4259
4260	if (cmd_len != sizeof(*req))
4261		return -EPROTO;
4262
4263	scid = __le16_to_cpu(req->scid);
4264	dcid = __le16_to_cpu(req->dcid);
4265
4266	BT_DBG("scid 0x%4.4x dcid 0x%4.4x", scid, dcid);
4267
4268	mutex_lock(&conn->chan_lock);
4269
4270	chan = __l2cap_get_chan_by_scid(conn, dcid);
4271	if (!chan) {
4272		mutex_unlock(&conn->chan_lock);
4273		cmd_reject_invalid_cid(conn, cmd->ident, dcid, scid);
4274		return 0;
4275	}
4276
 
4277	l2cap_chan_lock(chan);
4278
4279	rsp.dcid = cpu_to_le16(chan->scid);
4280	rsp.scid = cpu_to_le16(chan->dcid);
4281	l2cap_send_cmd(conn, cmd->ident, L2CAP_DISCONN_RSP, sizeof(rsp), &rsp);
4282
4283	chan->ops->set_shutdown(chan);
4284
4285	l2cap_chan_hold(chan);
4286	l2cap_chan_del(chan, ECONNRESET);
4287
4288	l2cap_chan_unlock(chan);
4289
4290	chan->ops->close(chan);
 
 
4291	l2cap_chan_put(chan);
4292
4293	mutex_unlock(&conn->chan_lock);
4294
4295	return 0;
4296}
4297
4298static inline int l2cap_disconnect_rsp(struct l2cap_conn *conn,
4299				       struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4300				       u8 *data)
4301{
4302	struct l2cap_disconn_rsp *rsp = (struct l2cap_disconn_rsp *) data;
4303	u16 dcid, scid;
4304	struct l2cap_chan *chan;
4305
4306	if (cmd_len != sizeof(*rsp))
4307		return -EPROTO;
4308
4309	scid = __le16_to_cpu(rsp->scid);
4310	dcid = __le16_to_cpu(rsp->dcid);
4311
4312	BT_DBG("dcid 0x%4.4x scid 0x%4.4x", dcid, scid);
4313
4314	mutex_lock(&conn->chan_lock);
4315
4316	chan = __l2cap_get_chan_by_scid(conn, scid);
4317	if (!chan) {
4318		mutex_unlock(&conn->chan_lock);
4319		return 0;
4320	}
4321
 
4322	l2cap_chan_lock(chan);
4323
4324	l2cap_chan_hold(chan);
4325	l2cap_chan_del(chan, 0);
 
 
 
 
4326
4327	l2cap_chan_unlock(chan);
4328
4329	chan->ops->close(chan);
 
 
4330	l2cap_chan_put(chan);
4331
4332	mutex_unlock(&conn->chan_lock);
4333
4334	return 0;
4335}
4336
4337static inline int l2cap_information_req(struct l2cap_conn *conn,
4338					struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4339					u8 *data)
4340{
4341	struct l2cap_info_req *req = (struct l2cap_info_req *) data;
4342	u16 type;
4343
4344	if (cmd_len != sizeof(*req))
4345		return -EPROTO;
4346
4347	type = __le16_to_cpu(req->type);
4348
4349	BT_DBG("type 0x%4.4x", type);
4350
4351	if (type == L2CAP_IT_FEAT_MASK) {
4352		u8 buf[8];
4353		u32 feat_mask = l2cap_feat_mask;
4354		struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) buf;
4355		rsp->type   = cpu_to_le16(L2CAP_IT_FEAT_MASK);
4356		rsp->result = cpu_to_le16(L2CAP_IR_SUCCESS);
4357		if (!disable_ertm)
4358			feat_mask |= L2CAP_FEAT_ERTM | L2CAP_FEAT_STREAMING
4359				| L2CAP_FEAT_FCS;
4360		if (conn->local_fixed_chan & L2CAP_FC_A2MP)
4361			feat_mask |= L2CAP_FEAT_EXT_FLOW
4362				| L2CAP_FEAT_EXT_WINDOW;
4363
4364		put_unaligned_le32(feat_mask, rsp->data);
4365		l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(buf),
4366			       buf);
4367	} else if (type == L2CAP_IT_FIXED_CHAN) {
4368		u8 buf[12];
4369		struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) buf;
4370
4371		rsp->type   = cpu_to_le16(L2CAP_IT_FIXED_CHAN);
4372		rsp->result = cpu_to_le16(L2CAP_IR_SUCCESS);
4373		rsp->data[0] = conn->local_fixed_chan;
4374		memset(rsp->data + 1, 0, 7);
4375		l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(buf),
4376			       buf);
4377	} else {
4378		struct l2cap_info_rsp rsp;
4379		rsp.type   = cpu_to_le16(type);
4380		rsp.result = cpu_to_le16(L2CAP_IR_NOTSUPP);
4381		l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(rsp),
4382			       &rsp);
4383	}
4384
4385	return 0;
4386}
4387
4388static inline int l2cap_information_rsp(struct l2cap_conn *conn,
4389					struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4390					u8 *data)
4391{
4392	struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) data;
4393	u16 type, result;
4394
4395	if (cmd_len < sizeof(*rsp))
4396		return -EPROTO;
4397
4398	type   = __le16_to_cpu(rsp->type);
4399	result = __le16_to_cpu(rsp->result);
4400
4401	BT_DBG("type 0x%4.4x result 0x%2.2x", type, result);
4402
4403	/* L2CAP Info req/rsp are unbound to channels, add extra checks */
4404	if (cmd->ident != conn->info_ident ||
4405	    conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE)
4406		return 0;
4407
4408	cancel_delayed_work(&conn->info_timer);
4409
4410	if (result != L2CAP_IR_SUCCESS) {
4411		conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4412		conn->info_ident = 0;
4413
4414		l2cap_conn_start(conn);
4415
4416		return 0;
4417	}
4418
4419	switch (type) {
4420	case L2CAP_IT_FEAT_MASK:
4421		conn->feat_mask = get_unaligned_le32(rsp->data);
4422
4423		if (conn->feat_mask & L2CAP_FEAT_FIXED_CHAN) {
4424			struct l2cap_info_req req;
4425			req.type = cpu_to_le16(L2CAP_IT_FIXED_CHAN);
4426
4427			conn->info_ident = l2cap_get_ident(conn);
4428
4429			l2cap_send_cmd(conn, conn->info_ident,
4430				       L2CAP_INFO_REQ, sizeof(req), &req);
4431		} else {
4432			conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4433			conn->info_ident = 0;
4434
4435			l2cap_conn_start(conn);
4436		}
4437		break;
4438
4439	case L2CAP_IT_FIXED_CHAN:
4440		conn->remote_fixed_chan = rsp->data[0];
4441		conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4442		conn->info_ident = 0;
4443
4444		l2cap_conn_start(conn);
4445		break;
4446	}
4447
4448	return 0;
4449}
4450
4451static int l2cap_create_channel_req(struct l2cap_conn *conn,
4452				    struct l2cap_cmd_hdr *cmd,
4453				    u16 cmd_len, void *data)
4454{
4455	struct l2cap_create_chan_req *req = data;
4456	struct l2cap_create_chan_rsp rsp;
4457	struct l2cap_chan *chan;
4458	struct hci_dev *hdev;
4459	u16 psm, scid;
4460
4461	if (cmd_len != sizeof(*req))
4462		return -EPROTO;
4463
4464	if (!(conn->local_fixed_chan & L2CAP_FC_A2MP))
4465		return -EINVAL;
4466
4467	psm = le16_to_cpu(req->psm);
4468	scid = le16_to_cpu(req->scid);
4469
4470	BT_DBG("psm 0x%2.2x, scid 0x%4.4x, amp_id %d", psm, scid, req->amp_id);
4471
4472	/* For controller id 0 make BR/EDR connection */
4473	if (req->amp_id == AMP_ID_BREDR) {
4474		l2cap_connect(conn, cmd, data, L2CAP_CREATE_CHAN_RSP,
4475			      req->amp_id);
4476		return 0;
4477	}
4478
4479	/* Validate AMP controller id */
4480	hdev = hci_dev_get(req->amp_id);
4481	if (!hdev)
4482		goto error;
4483
4484	if (hdev->dev_type != HCI_AMP || !test_bit(HCI_UP, &hdev->flags)) {
4485		hci_dev_put(hdev);
4486		goto error;
4487	}
4488
4489	chan = l2cap_connect(conn, cmd, data, L2CAP_CREATE_CHAN_RSP,
4490			     req->amp_id);
4491	if (chan) {
4492		struct amp_mgr *mgr = conn->hcon->amp_mgr;
4493		struct hci_conn *hs_hcon;
4494
4495		hs_hcon = hci_conn_hash_lookup_ba(hdev, AMP_LINK,
4496						  &conn->hcon->dst);
4497		if (!hs_hcon) {
4498			hci_dev_put(hdev);
4499			cmd_reject_invalid_cid(conn, cmd->ident, chan->scid,
4500					       chan->dcid);
4501			return 0;
4502		}
4503
4504		BT_DBG("mgr %p bredr_chan %p hs_hcon %p", mgr, chan, hs_hcon);
4505
4506		mgr->bredr_chan = chan;
4507		chan->hs_hcon = hs_hcon;
4508		chan->fcs = L2CAP_FCS_NONE;
4509		conn->mtu = hdev->block_mtu;
4510	}
4511
4512	hci_dev_put(hdev);
4513
4514	return 0;
4515
4516error:
4517	rsp.dcid = 0;
4518	rsp.scid = cpu_to_le16(scid);
4519	rsp.result = cpu_to_le16(L2CAP_CR_BAD_AMP);
4520	rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
4521
4522	l2cap_send_cmd(conn, cmd->ident, L2CAP_CREATE_CHAN_RSP,
4523		       sizeof(rsp), &rsp);
4524
4525	return 0;
4526}
4527
4528static void l2cap_send_move_chan_req(struct l2cap_chan *chan, u8 dest_amp_id)
4529{
4530	struct l2cap_move_chan_req req;
4531	u8 ident;
4532
4533	BT_DBG("chan %p, dest_amp_id %d", chan, dest_amp_id);
4534
4535	ident = l2cap_get_ident(chan->conn);
4536	chan->ident = ident;
4537
4538	req.icid = cpu_to_le16(chan->scid);
4539	req.dest_amp_id = dest_amp_id;
4540
4541	l2cap_send_cmd(chan->conn, ident, L2CAP_MOVE_CHAN_REQ, sizeof(req),
4542		       &req);
4543
4544	__set_chan_timer(chan, L2CAP_MOVE_TIMEOUT);
4545}
4546
4547static void l2cap_send_move_chan_rsp(struct l2cap_chan *chan, u16 result)
4548{
4549	struct l2cap_move_chan_rsp rsp;
4550
4551	BT_DBG("chan %p, result 0x%4.4x", chan, result);
4552
4553	rsp.icid = cpu_to_le16(chan->dcid);
4554	rsp.result = cpu_to_le16(result);
4555
4556	l2cap_send_cmd(chan->conn, chan->ident, L2CAP_MOVE_CHAN_RSP,
4557		       sizeof(rsp), &rsp);
4558}
4559
4560static void l2cap_send_move_chan_cfm(struct l2cap_chan *chan, u16 result)
4561{
4562	struct l2cap_move_chan_cfm cfm;
4563
4564	BT_DBG("chan %p, result 0x%4.4x", chan, result);
4565
4566	chan->ident = l2cap_get_ident(chan->conn);
4567
4568	cfm.icid = cpu_to_le16(chan->scid);
4569	cfm.result = cpu_to_le16(result);
4570
4571	l2cap_send_cmd(chan->conn, chan->ident, L2CAP_MOVE_CHAN_CFM,
4572		       sizeof(cfm), &cfm);
4573
4574	__set_chan_timer(chan, L2CAP_MOVE_TIMEOUT);
4575}
4576
4577static void l2cap_send_move_chan_cfm_icid(struct l2cap_conn *conn, u16 icid)
4578{
4579	struct l2cap_move_chan_cfm cfm;
4580
4581	BT_DBG("conn %p, icid 0x%4.4x", conn, icid);
4582
4583	cfm.icid = cpu_to_le16(icid);
4584	cfm.result = cpu_to_le16(L2CAP_MC_UNCONFIRMED);
4585
4586	l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_MOVE_CHAN_CFM,
4587		       sizeof(cfm), &cfm);
4588}
4589
4590static void l2cap_send_move_chan_cfm_rsp(struct l2cap_conn *conn, u8 ident,
4591					 u16 icid)
4592{
4593	struct l2cap_move_chan_cfm_rsp rsp;
4594
4595	BT_DBG("icid 0x%4.4x", icid);
4596
4597	rsp.icid = cpu_to_le16(icid);
4598	l2cap_send_cmd(conn, ident, L2CAP_MOVE_CHAN_CFM_RSP, sizeof(rsp), &rsp);
4599}
4600
4601static void __release_logical_link(struct l2cap_chan *chan)
4602{
4603	chan->hs_hchan = NULL;
4604	chan->hs_hcon = NULL;
4605
4606	/* Placeholder - release the logical link */
4607}
4608
4609static void l2cap_logical_fail(struct l2cap_chan *chan)
4610{
4611	/* Logical link setup failed */
4612	if (chan->state != BT_CONNECTED) {
4613		/* Create channel failure, disconnect */
4614		l2cap_send_disconn_req(chan, ECONNRESET);
4615		return;
4616	}
4617
4618	switch (chan->move_role) {
4619	case L2CAP_MOVE_ROLE_RESPONDER:
4620		l2cap_move_done(chan);
4621		l2cap_send_move_chan_rsp(chan, L2CAP_MR_NOT_SUPP);
4622		break;
4623	case L2CAP_MOVE_ROLE_INITIATOR:
4624		if (chan->move_state == L2CAP_MOVE_WAIT_LOGICAL_COMP ||
4625		    chan->move_state == L2CAP_MOVE_WAIT_LOGICAL_CFM) {
4626			/* Remote has only sent pending or
4627			 * success responses, clean up
4628			 */
4629			l2cap_move_done(chan);
4630		}
4631
4632		/* Other amp move states imply that the move
4633		 * has already aborted
4634		 */
4635		l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
4636		break;
4637	}
4638}
4639
4640static void l2cap_logical_finish_create(struct l2cap_chan *chan,
4641					struct hci_chan *hchan)
4642{
4643	struct l2cap_conf_rsp rsp;
4644
4645	chan->hs_hchan = hchan;
4646	chan->hs_hcon->l2cap_data = chan->conn;
4647
4648	l2cap_send_efs_conf_rsp(chan, &rsp, chan->ident, 0);
4649
4650	if (test_bit(CONF_INPUT_DONE, &chan->conf_state)) {
4651		int err;
4652
4653		set_default_fcs(chan);
4654
4655		err = l2cap_ertm_init(chan);
4656		if (err < 0)
4657			l2cap_send_disconn_req(chan, -err);
4658		else
4659			l2cap_chan_ready(chan);
4660	}
4661}
4662
4663static void l2cap_logical_finish_move(struct l2cap_chan *chan,
4664				      struct hci_chan *hchan)
4665{
4666	chan->hs_hcon = hchan->conn;
4667	chan->hs_hcon->l2cap_data = chan->conn;
4668
4669	BT_DBG("move_state %d", chan->move_state);
4670
4671	switch (chan->move_state) {
4672	case L2CAP_MOVE_WAIT_LOGICAL_COMP:
4673		/* Move confirm will be sent after a success
4674		 * response is received
4675		 */
4676		chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
4677		break;
4678	case L2CAP_MOVE_WAIT_LOGICAL_CFM:
4679		if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
4680			chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
4681		} else if (chan->move_role == L2CAP_MOVE_ROLE_INITIATOR) {
4682			chan->move_state = L2CAP_MOVE_WAIT_CONFIRM_RSP;
4683			l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
4684		} else if (chan->move_role == L2CAP_MOVE_ROLE_RESPONDER) {
4685			chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
4686			l2cap_send_move_chan_rsp(chan, L2CAP_MR_SUCCESS);
4687		}
4688		break;
4689	default:
4690		/* Move was not in expected state, free the channel */
4691		__release_logical_link(chan);
4692
4693		chan->move_state = L2CAP_MOVE_STABLE;
4694	}
4695}
4696
4697/* Call with chan locked */
4698void l2cap_logical_cfm(struct l2cap_chan *chan, struct hci_chan *hchan,
4699		       u8 status)
4700{
4701	BT_DBG("chan %p, hchan %p, status %d", chan, hchan, status);
4702
4703	if (status) {
4704		l2cap_logical_fail(chan);
4705		__release_logical_link(chan);
4706		return;
4707	}
4708
4709	if (chan->state != BT_CONNECTED) {
4710		/* Ignore logical link if channel is on BR/EDR */
4711		if (chan->local_amp_id != AMP_ID_BREDR)
4712			l2cap_logical_finish_create(chan, hchan);
4713	} else {
4714		l2cap_logical_finish_move(chan, hchan);
4715	}
4716}
4717
4718void l2cap_move_start(struct l2cap_chan *chan)
4719{
4720	BT_DBG("chan %p", chan);
4721
4722	if (chan->local_amp_id == AMP_ID_BREDR) {
4723		if (chan->chan_policy != BT_CHANNEL_POLICY_AMP_PREFERRED)
4724			return;
4725		chan->move_role = L2CAP_MOVE_ROLE_INITIATOR;
4726		chan->move_state = L2CAP_MOVE_WAIT_PREPARE;
4727		/* Placeholder - start physical link setup */
4728	} else {
4729		chan->move_role = L2CAP_MOVE_ROLE_INITIATOR;
4730		chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
4731		chan->move_id = 0;
4732		l2cap_move_setup(chan);
4733		l2cap_send_move_chan_req(chan, 0);
4734	}
4735}
4736
4737static void l2cap_do_create(struct l2cap_chan *chan, int result,
4738			    u8 local_amp_id, u8 remote_amp_id)
4739{
4740	BT_DBG("chan %p state %s %u -> %u", chan, state_to_string(chan->state),
4741	       local_amp_id, remote_amp_id);
4742
4743	chan->fcs = L2CAP_FCS_NONE;
4744
4745	/* Outgoing channel on AMP */
4746	if (chan->state == BT_CONNECT) {
4747		if (result == L2CAP_CR_SUCCESS) {
4748			chan->local_amp_id = local_amp_id;
4749			l2cap_send_create_chan_req(chan, remote_amp_id);
4750		} else {
4751			/* Revert to BR/EDR connect */
4752			l2cap_send_conn_req(chan);
4753		}
4754
4755		return;
4756	}
4757
4758	/* Incoming channel on AMP */
4759	if (__l2cap_no_conn_pending(chan)) {
4760		struct l2cap_conn_rsp rsp;
4761		char buf[128];
4762		rsp.scid = cpu_to_le16(chan->dcid);
4763		rsp.dcid = cpu_to_le16(chan->scid);
4764
4765		if (result == L2CAP_CR_SUCCESS) {
4766			/* Send successful response */
4767			rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
4768			rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
4769		} else {
4770			/* Send negative response */
4771			rsp.result = cpu_to_le16(L2CAP_CR_NO_MEM);
4772			rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
4773		}
4774
4775		l2cap_send_cmd(chan->conn, chan->ident, L2CAP_CREATE_CHAN_RSP,
4776			       sizeof(rsp), &rsp);
4777
4778		if (result == L2CAP_CR_SUCCESS) {
4779			l2cap_state_change(chan, BT_CONFIG);
4780			set_bit(CONF_REQ_SENT, &chan->conf_state);
4781			l2cap_send_cmd(chan->conn, l2cap_get_ident(chan->conn),
4782				       L2CAP_CONF_REQ,
4783				       l2cap_build_conf_req(chan, buf), buf);
4784			chan->num_conf_req++;
4785		}
4786	}
4787}
4788
4789static void l2cap_do_move_initiate(struct l2cap_chan *chan, u8 local_amp_id,
4790				   u8 remote_amp_id)
4791{
4792	l2cap_move_setup(chan);
4793	chan->move_id = local_amp_id;
4794	chan->move_state = L2CAP_MOVE_WAIT_RSP;
4795
4796	l2cap_send_move_chan_req(chan, remote_amp_id);
4797}
4798
4799static void l2cap_do_move_respond(struct l2cap_chan *chan, int result)
4800{
4801	struct hci_chan *hchan = NULL;
4802
4803	/* Placeholder - get hci_chan for logical link */
4804
4805	if (hchan) {
4806		if (hchan->state == BT_CONNECTED) {
4807			/* Logical link is ready to go */
4808			chan->hs_hcon = hchan->conn;
4809			chan->hs_hcon->l2cap_data = chan->conn;
4810			chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
4811			l2cap_send_move_chan_rsp(chan, L2CAP_MR_SUCCESS);
4812
4813			l2cap_logical_cfm(chan, hchan, L2CAP_MR_SUCCESS);
4814		} else {
4815			/* Wait for logical link to be ready */
4816			chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
4817		}
4818	} else {
4819		/* Logical link not available */
4820		l2cap_send_move_chan_rsp(chan, L2CAP_MR_NOT_ALLOWED);
4821	}
4822}
4823
4824static void l2cap_do_move_cancel(struct l2cap_chan *chan, int result)
4825{
4826	if (chan->move_role == L2CAP_MOVE_ROLE_RESPONDER) {
4827		u8 rsp_result;
4828		if (result == -EINVAL)
4829			rsp_result = L2CAP_MR_BAD_ID;
4830		else
4831			rsp_result = L2CAP_MR_NOT_ALLOWED;
4832
4833		l2cap_send_move_chan_rsp(chan, rsp_result);
4834	}
4835
4836	chan->move_role = L2CAP_MOVE_ROLE_NONE;
4837	chan->move_state = L2CAP_MOVE_STABLE;
4838
4839	/* Restart data transmission */
4840	l2cap_ertm_send(chan);
4841}
4842
4843/* Invoke with locked chan */
4844void __l2cap_physical_cfm(struct l2cap_chan *chan, int result)
4845{
4846	u8 local_amp_id = chan->local_amp_id;
4847	u8 remote_amp_id = chan->remote_amp_id;
4848
4849	BT_DBG("chan %p, result %d, local_amp_id %d, remote_amp_id %d",
4850	       chan, result, local_amp_id, remote_amp_id);
4851
4852	if (chan->state == BT_DISCONN || chan->state == BT_CLOSED) {
4853		l2cap_chan_unlock(chan);
4854		return;
4855	}
4856
4857	if (chan->state != BT_CONNECTED) {
4858		l2cap_do_create(chan, result, local_amp_id, remote_amp_id);
4859	} else if (result != L2CAP_MR_SUCCESS) {
4860		l2cap_do_move_cancel(chan, result);
4861	} else {
4862		switch (chan->move_role) {
4863		case L2CAP_MOVE_ROLE_INITIATOR:
4864			l2cap_do_move_initiate(chan, local_amp_id,
4865					       remote_amp_id);
4866			break;
4867		case L2CAP_MOVE_ROLE_RESPONDER:
4868			l2cap_do_move_respond(chan, result);
4869			break;
4870		default:
4871			l2cap_do_move_cancel(chan, result);
4872			break;
4873		}
4874	}
4875}
4876
4877static inline int l2cap_move_channel_req(struct l2cap_conn *conn,
4878					 struct l2cap_cmd_hdr *cmd,
4879					 u16 cmd_len, void *data)
4880{
4881	struct l2cap_move_chan_req *req = data;
4882	struct l2cap_move_chan_rsp rsp;
4883	struct l2cap_chan *chan;
4884	u16 icid = 0;
4885	u16 result = L2CAP_MR_NOT_ALLOWED;
4886
4887	if (cmd_len != sizeof(*req))
4888		return -EPROTO;
4889
4890	icid = le16_to_cpu(req->icid);
4891
4892	BT_DBG("icid 0x%4.4x, dest_amp_id %d", icid, req->dest_amp_id);
4893
4894	if (!(conn->local_fixed_chan & L2CAP_FC_A2MP))
4895		return -EINVAL;
4896
4897	chan = l2cap_get_chan_by_dcid(conn, icid);
4898	if (!chan) {
4899		rsp.icid = cpu_to_le16(icid);
4900		rsp.result = cpu_to_le16(L2CAP_MR_NOT_ALLOWED);
4901		l2cap_send_cmd(conn, cmd->ident, L2CAP_MOVE_CHAN_RSP,
4902			       sizeof(rsp), &rsp);
4903		return 0;
4904	}
4905
4906	chan->ident = cmd->ident;
4907
4908	if (chan->scid < L2CAP_CID_DYN_START ||
4909	    chan->chan_policy == BT_CHANNEL_POLICY_BREDR_ONLY ||
4910	    (chan->mode != L2CAP_MODE_ERTM &&
4911	     chan->mode != L2CAP_MODE_STREAMING)) {
4912		result = L2CAP_MR_NOT_ALLOWED;
4913		goto send_move_response;
4914	}
4915
4916	if (chan->local_amp_id == req->dest_amp_id) {
4917		result = L2CAP_MR_SAME_ID;
4918		goto send_move_response;
4919	}
4920
4921	if (req->dest_amp_id != AMP_ID_BREDR) {
4922		struct hci_dev *hdev;
4923		hdev = hci_dev_get(req->dest_amp_id);
4924		if (!hdev || hdev->dev_type != HCI_AMP ||
4925		    !test_bit(HCI_UP, &hdev->flags)) {
4926			if (hdev)
4927				hci_dev_put(hdev);
4928
4929			result = L2CAP_MR_BAD_ID;
4930			goto send_move_response;
4931		}
4932		hci_dev_put(hdev);
4933	}
4934
4935	/* Detect a move collision.  Only send a collision response
4936	 * if this side has "lost", otherwise proceed with the move.
4937	 * The winner has the larger bd_addr.
4938	 */
4939	if ((__chan_is_moving(chan) ||
4940	     chan->move_role != L2CAP_MOVE_ROLE_NONE) &&
4941	    bacmp(&conn->hcon->src, &conn->hcon->dst) > 0) {
4942		result = L2CAP_MR_COLLISION;
4943		goto send_move_response;
4944	}
4945
4946	chan->move_role = L2CAP_MOVE_ROLE_RESPONDER;
4947	l2cap_move_setup(chan);
4948	chan->move_id = req->dest_amp_id;
4949	icid = chan->dcid;
4950
4951	if (req->dest_amp_id == AMP_ID_BREDR) {
4952		/* Moving to BR/EDR */
4953		if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
4954			chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
4955			result = L2CAP_MR_PEND;
4956		} else {
4957			chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
4958			result = L2CAP_MR_SUCCESS;
4959		}
4960	} else {
4961		chan->move_state = L2CAP_MOVE_WAIT_PREPARE;
4962		/* Placeholder - uncomment when amp functions are available */
4963		/*amp_accept_physical(chan, req->dest_amp_id);*/
4964		result = L2CAP_MR_PEND;
4965	}
4966
4967send_move_response:
4968	l2cap_send_move_chan_rsp(chan, result);
4969
4970	l2cap_chan_unlock(chan);
4971
4972	return 0;
4973}
4974
4975static void l2cap_move_continue(struct l2cap_conn *conn, u16 icid, u16 result)
4976{
4977	struct l2cap_chan *chan;
4978	struct hci_chan *hchan = NULL;
4979
4980	chan = l2cap_get_chan_by_scid(conn, icid);
4981	if (!chan) {
4982		l2cap_send_move_chan_cfm_icid(conn, icid);
4983		return;
4984	}
4985
4986	__clear_chan_timer(chan);
4987	if (result == L2CAP_MR_PEND)
4988		__set_chan_timer(chan, L2CAP_MOVE_ERTX_TIMEOUT);
4989
4990	switch (chan->move_state) {
4991	case L2CAP_MOVE_WAIT_LOGICAL_COMP:
4992		/* Move confirm will be sent when logical link
4993		 * is complete.
4994		 */
4995		chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
4996		break;
4997	case L2CAP_MOVE_WAIT_RSP_SUCCESS:
4998		if (result == L2CAP_MR_PEND) {
4999			break;
5000		} else if (test_bit(CONN_LOCAL_BUSY,
5001				    &chan->conn_state)) {
5002			chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
5003		} else {
5004			/* Logical link is up or moving to BR/EDR,
5005			 * proceed with move
5006			 */
5007			chan->move_state = L2CAP_MOVE_WAIT_CONFIRM_RSP;
5008			l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
5009		}
5010		break;
5011	case L2CAP_MOVE_WAIT_RSP:
5012		/* Moving to AMP */
5013		if (result == L2CAP_MR_SUCCESS) {
5014			/* Remote is ready, send confirm immediately
5015			 * after logical link is ready
5016			 */
5017			chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
5018		} else {
5019			/* Both logical link and move success
5020			 * are required to confirm
5021			 */
5022			chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_COMP;
5023		}
5024
5025		/* Placeholder - get hci_chan for logical link */
5026		if (!hchan) {
5027			/* Logical link not available */
5028			l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5029			break;
5030		}
5031
5032		/* If the logical link is not yet connected, do not
5033		 * send confirmation.
5034		 */
5035		if (hchan->state != BT_CONNECTED)
5036			break;
5037
5038		/* Logical link is already ready to go */
5039
5040		chan->hs_hcon = hchan->conn;
5041		chan->hs_hcon->l2cap_data = chan->conn;
5042
5043		if (result == L2CAP_MR_SUCCESS) {
5044			/* Can confirm now */
5045			l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
5046		} else {
5047			/* Now only need move success
5048			 * to confirm
5049			 */
5050			chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
5051		}
5052
5053		l2cap_logical_cfm(chan, hchan, L2CAP_MR_SUCCESS);
5054		break;
5055	default:
5056		/* Any other amp move state means the move failed. */
5057		chan->move_id = chan->local_amp_id;
5058		l2cap_move_done(chan);
5059		l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5060	}
5061
5062	l2cap_chan_unlock(chan);
5063}
5064
5065static void l2cap_move_fail(struct l2cap_conn *conn, u8 ident, u16 icid,
5066			    u16 result)
5067{
5068	struct l2cap_chan *chan;
5069
5070	chan = l2cap_get_chan_by_ident(conn, ident);
5071	if (!chan) {
5072		/* Could not locate channel, icid is best guess */
5073		l2cap_send_move_chan_cfm_icid(conn, icid);
5074		return;
5075	}
5076
5077	__clear_chan_timer(chan);
5078
5079	if (chan->move_role == L2CAP_MOVE_ROLE_INITIATOR) {
5080		if (result == L2CAP_MR_COLLISION) {
5081			chan->move_role = L2CAP_MOVE_ROLE_RESPONDER;
5082		} else {
5083			/* Cleanup - cancel move */
5084			chan->move_id = chan->local_amp_id;
5085			l2cap_move_done(chan);
5086		}
5087	}
5088
5089	l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5090
5091	l2cap_chan_unlock(chan);
5092}
5093
5094static int l2cap_move_channel_rsp(struct l2cap_conn *conn,
5095				  struct l2cap_cmd_hdr *cmd,
5096				  u16 cmd_len, void *data)
5097{
5098	struct l2cap_move_chan_rsp *rsp = data;
5099	u16 icid, result;
5100
5101	if (cmd_len != sizeof(*rsp))
5102		return -EPROTO;
5103
5104	icid = le16_to_cpu(rsp->icid);
5105	result = le16_to_cpu(rsp->result);
5106
5107	BT_DBG("icid 0x%4.4x, result 0x%4.4x", icid, result);
5108
5109	if (result == L2CAP_MR_SUCCESS || result == L2CAP_MR_PEND)
5110		l2cap_move_continue(conn, icid, result);
5111	else
5112		l2cap_move_fail(conn, cmd->ident, icid, result);
5113
5114	return 0;
5115}
5116
5117static int l2cap_move_channel_confirm(struct l2cap_conn *conn,
5118				      struct l2cap_cmd_hdr *cmd,
5119				      u16 cmd_len, void *data)
5120{
5121	struct l2cap_move_chan_cfm *cfm = data;
5122	struct l2cap_chan *chan;
5123	u16 icid, result;
5124
5125	if (cmd_len != sizeof(*cfm))
5126		return -EPROTO;
5127
5128	icid = le16_to_cpu(cfm->icid);
5129	result = le16_to_cpu(cfm->result);
5130
5131	BT_DBG("icid 0x%4.4x, result 0x%4.4x", icid, result);
5132
5133	chan = l2cap_get_chan_by_dcid(conn, icid);
5134	if (!chan) {
5135		/* Spec requires a response even if the icid was not found */
5136		l2cap_send_move_chan_cfm_rsp(conn, cmd->ident, icid);
5137		return 0;
5138	}
5139
5140	if (chan->move_state == L2CAP_MOVE_WAIT_CONFIRM) {
5141		if (result == L2CAP_MC_CONFIRMED) {
5142			chan->local_amp_id = chan->move_id;
5143			if (chan->local_amp_id == AMP_ID_BREDR)
5144				__release_logical_link(chan);
5145		} else {
5146			chan->move_id = chan->local_amp_id;
5147		}
5148
5149		l2cap_move_done(chan);
5150	}
5151
5152	l2cap_send_move_chan_cfm_rsp(conn, cmd->ident, icid);
5153
5154	l2cap_chan_unlock(chan);
5155
5156	return 0;
5157}
5158
5159static inline int l2cap_move_channel_confirm_rsp(struct l2cap_conn *conn,
5160						 struct l2cap_cmd_hdr *cmd,
5161						 u16 cmd_len, void *data)
5162{
5163	struct l2cap_move_chan_cfm_rsp *rsp = data;
5164	struct l2cap_chan *chan;
5165	u16 icid;
5166
5167	if (cmd_len != sizeof(*rsp))
5168		return -EPROTO;
5169
5170	icid = le16_to_cpu(rsp->icid);
5171
5172	BT_DBG("icid 0x%4.4x", icid);
5173
5174	chan = l2cap_get_chan_by_scid(conn, icid);
5175	if (!chan)
5176		return 0;
5177
5178	__clear_chan_timer(chan);
5179
5180	if (chan->move_state == L2CAP_MOVE_WAIT_CONFIRM_RSP) {
5181		chan->local_amp_id = chan->move_id;
5182
5183		if (chan->local_amp_id == AMP_ID_BREDR && chan->hs_hchan)
5184			__release_logical_link(chan);
5185
5186		l2cap_move_done(chan);
5187	}
5188
5189	l2cap_chan_unlock(chan);
5190
5191	return 0;
5192}
5193
5194static inline int l2cap_conn_param_update_req(struct l2cap_conn *conn,
5195					      struct l2cap_cmd_hdr *cmd,
5196					      u16 cmd_len, u8 *data)
5197{
5198	struct hci_conn *hcon = conn->hcon;
5199	struct l2cap_conn_param_update_req *req;
5200	struct l2cap_conn_param_update_rsp rsp;
5201	u16 min, max, latency, to_multiplier;
5202	int err;
5203
5204	if (hcon->role != HCI_ROLE_MASTER)
5205		return -EINVAL;
5206
5207	if (cmd_len != sizeof(struct l2cap_conn_param_update_req))
5208		return -EPROTO;
5209
5210	req = (struct l2cap_conn_param_update_req *) data;
5211	min		= __le16_to_cpu(req->min);
5212	max		= __le16_to_cpu(req->max);
5213	latency		= __le16_to_cpu(req->latency);
5214	to_multiplier	= __le16_to_cpu(req->to_multiplier);
5215
5216	BT_DBG("min 0x%4.4x max 0x%4.4x latency: 0x%4.4x Timeout: 0x%4.4x",
5217	       min, max, latency, to_multiplier);
5218
5219	memset(&rsp, 0, sizeof(rsp));
5220
5221	err = hci_check_conn_params(min, max, latency, to_multiplier);
5222	if (err)
5223		rsp.result = cpu_to_le16(L2CAP_CONN_PARAM_REJECTED);
5224	else
5225		rsp.result = cpu_to_le16(L2CAP_CONN_PARAM_ACCEPTED);
5226
5227	l2cap_send_cmd(conn, cmd->ident, L2CAP_CONN_PARAM_UPDATE_RSP,
5228		       sizeof(rsp), &rsp);
5229
5230	if (!err) {
5231		u8 store_hint;
5232
5233		store_hint = hci_le_conn_update(hcon, min, max, latency,
5234						to_multiplier);
5235		mgmt_new_conn_param(hcon->hdev, &hcon->dst, hcon->dst_type,
5236				    store_hint, min, max, latency,
5237				    to_multiplier);
5238
5239	}
5240
5241	return 0;
5242}
5243
5244static int l2cap_le_connect_rsp(struct l2cap_conn *conn,
5245				struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5246				u8 *data)
5247{
5248	struct l2cap_le_conn_rsp *rsp = (struct l2cap_le_conn_rsp *) data;
5249	struct hci_conn *hcon = conn->hcon;
5250	u16 dcid, mtu, mps, credits, result;
5251	struct l2cap_chan *chan;
5252	int err, sec_level;
5253
5254	if (cmd_len < sizeof(*rsp))
5255		return -EPROTO;
5256
5257	dcid    = __le16_to_cpu(rsp->dcid);
5258	mtu     = __le16_to_cpu(rsp->mtu);
5259	mps     = __le16_to_cpu(rsp->mps);
5260	credits = __le16_to_cpu(rsp->credits);
5261	result  = __le16_to_cpu(rsp->result);
5262
5263	if (result == L2CAP_CR_SUCCESS && (mtu < 23 || mps < 23 ||
5264					   dcid < L2CAP_CID_DYN_START ||
5265					   dcid > L2CAP_CID_LE_DYN_END))
5266		return -EPROTO;
5267
5268	BT_DBG("dcid 0x%4.4x mtu %u mps %u credits %u result 0x%2.2x",
5269	       dcid, mtu, mps, credits, result);
5270
5271	mutex_lock(&conn->chan_lock);
5272
5273	chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
5274	if (!chan) {
5275		err = -EBADSLT;
5276		goto unlock;
5277	}
5278
5279	err = 0;
5280
5281	l2cap_chan_lock(chan);
5282
5283	switch (result) {
5284	case L2CAP_CR_SUCCESS:
5285		if (__l2cap_get_chan_by_dcid(conn, dcid)) {
5286			err = -EBADSLT;
5287			break;
5288		}
5289
5290		chan->ident = 0;
5291		chan->dcid = dcid;
5292		chan->omtu = mtu;
5293		chan->remote_mps = mps;
5294		chan->tx_credits = credits;
5295		l2cap_chan_ready(chan);
5296		break;
5297
5298	case L2CAP_CR_AUTHENTICATION:
5299	case L2CAP_CR_ENCRYPTION:
5300		/* If we already have MITM protection we can't do
5301		 * anything.
5302		 */
5303		if (hcon->sec_level > BT_SECURITY_MEDIUM) {
5304			l2cap_chan_del(chan, ECONNREFUSED);
5305			break;
5306		}
5307
5308		sec_level = hcon->sec_level + 1;
5309		if (chan->sec_level < sec_level)
5310			chan->sec_level = sec_level;
5311
5312		/* We'll need to send a new Connect Request */
5313		clear_bit(FLAG_LE_CONN_REQ_SENT, &chan->flags);
5314
5315		smp_conn_security(hcon, chan->sec_level);
5316		break;
5317
5318	default:
5319		l2cap_chan_del(chan, ECONNREFUSED);
5320		break;
5321	}
5322
5323	l2cap_chan_unlock(chan);
5324
5325unlock:
5326	mutex_unlock(&conn->chan_lock);
5327
5328	return err;
5329}
5330
5331static inline int l2cap_bredr_sig_cmd(struct l2cap_conn *conn,
5332				      struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5333				      u8 *data)
5334{
5335	int err = 0;
5336
5337	switch (cmd->code) {
5338	case L2CAP_COMMAND_REJ:
5339		l2cap_command_rej(conn, cmd, cmd_len, data);
5340		break;
5341
5342	case L2CAP_CONN_REQ:
5343		err = l2cap_connect_req(conn, cmd, cmd_len, data);
5344		break;
5345
5346	case L2CAP_CONN_RSP:
5347	case L2CAP_CREATE_CHAN_RSP:
5348		l2cap_connect_create_rsp(conn, cmd, cmd_len, data);
5349		break;
5350
5351	case L2CAP_CONF_REQ:
5352		err = l2cap_config_req(conn, cmd, cmd_len, data);
5353		break;
5354
5355	case L2CAP_CONF_RSP:
5356		l2cap_config_rsp(conn, cmd, cmd_len, data);
5357		break;
5358
5359	case L2CAP_DISCONN_REQ:
5360		err = l2cap_disconnect_req(conn, cmd, cmd_len, data);
5361		break;
5362
5363	case L2CAP_DISCONN_RSP:
5364		l2cap_disconnect_rsp(conn, cmd, cmd_len, data);
5365		break;
5366
5367	case L2CAP_ECHO_REQ:
5368		l2cap_send_cmd(conn, cmd->ident, L2CAP_ECHO_RSP, cmd_len, data);
5369		break;
5370
5371	case L2CAP_ECHO_RSP:
5372		break;
5373
5374	case L2CAP_INFO_REQ:
5375		err = l2cap_information_req(conn, cmd, cmd_len, data);
5376		break;
5377
5378	case L2CAP_INFO_RSP:
5379		l2cap_information_rsp(conn, cmd, cmd_len, data);
5380		break;
5381
5382	case L2CAP_CREATE_CHAN_REQ:
5383		err = l2cap_create_channel_req(conn, cmd, cmd_len, data);
5384		break;
5385
5386	case L2CAP_MOVE_CHAN_REQ:
5387		err = l2cap_move_channel_req(conn, cmd, cmd_len, data);
5388		break;
5389
5390	case L2CAP_MOVE_CHAN_RSP:
5391		l2cap_move_channel_rsp(conn, cmd, cmd_len, data);
5392		break;
5393
5394	case L2CAP_MOVE_CHAN_CFM:
5395		err = l2cap_move_channel_confirm(conn, cmd, cmd_len, data);
5396		break;
5397
5398	case L2CAP_MOVE_CHAN_CFM_RSP:
5399		l2cap_move_channel_confirm_rsp(conn, cmd, cmd_len, data);
5400		break;
5401
5402	default:
5403		BT_ERR("Unknown BR/EDR signaling command 0x%2.2x", cmd->code);
5404		err = -EINVAL;
5405		break;
5406	}
5407
5408	return err;
5409}
5410
5411static int l2cap_le_connect_req(struct l2cap_conn *conn,
5412				struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5413				u8 *data)
5414{
5415	struct l2cap_le_conn_req *req = (struct l2cap_le_conn_req *) data;
5416	struct l2cap_le_conn_rsp rsp;
5417	struct l2cap_chan *chan, *pchan;
5418	u16 dcid, scid, credits, mtu, mps;
5419	__le16 psm;
5420	u8 result;
5421
5422	if (cmd_len != sizeof(*req))
5423		return -EPROTO;
5424
5425	scid = __le16_to_cpu(req->scid);
5426	mtu  = __le16_to_cpu(req->mtu);
5427	mps  = __le16_to_cpu(req->mps);
5428	psm  = req->psm;
5429	dcid = 0;
5430	credits = 0;
5431
5432	if (mtu < 23 || mps < 23)
5433		return -EPROTO;
5434
5435	BT_DBG("psm 0x%2.2x scid 0x%4.4x mtu %u mps %u", __le16_to_cpu(psm),
5436	       scid, mtu, mps);
5437
5438	/* Check if we have socket listening on psm */
5439	pchan = l2cap_global_chan_by_psm(BT_LISTEN, psm, &conn->hcon->src,
5440					 &conn->hcon->dst, LE_LINK);
5441	if (!pchan) {
5442		result = L2CAP_CR_BAD_PSM;
5443		chan = NULL;
5444		goto response;
5445	}
5446
5447	mutex_lock(&conn->chan_lock);
5448	l2cap_chan_lock(pchan);
5449
5450	if (!smp_sufficient_security(conn->hcon, pchan->sec_level,
5451				     SMP_ALLOW_STK)) {
5452		result = L2CAP_CR_AUTHENTICATION;
5453		chan = NULL;
5454		goto response_unlock;
5455	}
5456
5457	/* Check for valid dynamic CID range */
5458	if (scid < L2CAP_CID_DYN_START || scid > L2CAP_CID_LE_DYN_END) {
5459		result = L2CAP_CR_INVALID_SCID;
5460		chan = NULL;
5461		goto response_unlock;
5462	}
5463
5464	/* Check if we already have channel with that dcid */
5465	if (__l2cap_get_chan_by_dcid(conn, scid)) {
5466		result = L2CAP_CR_SCID_IN_USE;
5467		chan = NULL;
5468		goto response_unlock;
5469	}
5470
5471	chan = pchan->ops->new_connection(pchan);
5472	if (!chan) {
5473		result = L2CAP_CR_NO_MEM;
5474		goto response_unlock;
5475	}
5476
5477	l2cap_le_flowctl_init(chan);
5478
5479	bacpy(&chan->src, &conn->hcon->src);
5480	bacpy(&chan->dst, &conn->hcon->dst);
5481	chan->src_type = bdaddr_src_type(conn->hcon);
5482	chan->dst_type = bdaddr_dst_type(conn->hcon);
5483	chan->psm  = psm;
5484	chan->dcid = scid;
5485	chan->omtu = mtu;
5486	chan->remote_mps = mps;
5487	chan->tx_credits = __le16_to_cpu(req->credits);
5488
5489	__l2cap_chan_add(conn, chan);
 
 
 
5490	dcid = chan->scid;
5491	credits = chan->rx_credits;
5492
5493	__set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
5494
5495	chan->ident = cmd->ident;
5496
5497	if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
5498		l2cap_state_change(chan, BT_CONNECT2);
5499		/* The following result value is actually not defined
5500		 * for LE CoC but we use it to let the function know
5501		 * that it should bail out after doing its cleanup
5502		 * instead of sending a response.
5503		 */
5504		result = L2CAP_CR_PEND;
5505		chan->ops->defer(chan);
5506	} else {
5507		l2cap_chan_ready(chan);
5508		result = L2CAP_CR_SUCCESS;
5509	}
5510
5511response_unlock:
5512	l2cap_chan_unlock(pchan);
5513	mutex_unlock(&conn->chan_lock);
5514	l2cap_chan_put(pchan);
5515
5516	if (result == L2CAP_CR_PEND)
5517		return 0;
5518
5519response:
5520	if (chan) {
5521		rsp.mtu = cpu_to_le16(chan->imtu);
5522		rsp.mps = cpu_to_le16(chan->mps);
5523	} else {
5524		rsp.mtu = 0;
5525		rsp.mps = 0;
5526	}
5527
5528	rsp.dcid    = cpu_to_le16(dcid);
5529	rsp.credits = cpu_to_le16(credits);
5530	rsp.result  = cpu_to_le16(result);
5531
5532	l2cap_send_cmd(conn, cmd->ident, L2CAP_LE_CONN_RSP, sizeof(rsp), &rsp);
5533
5534	return 0;
5535}
5536
5537static inline int l2cap_le_credits(struct l2cap_conn *conn,
5538				   struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5539				   u8 *data)
5540{
5541	struct l2cap_le_credits *pkt;
5542	struct l2cap_chan *chan;
5543	u16 cid, credits, max_credits;
5544
5545	if (cmd_len != sizeof(*pkt))
5546		return -EPROTO;
5547
5548	pkt = (struct l2cap_le_credits *) data;
5549	cid	= __le16_to_cpu(pkt->cid);
5550	credits	= __le16_to_cpu(pkt->credits);
5551
5552	BT_DBG("cid 0x%4.4x credits 0x%4.4x", cid, credits);
5553
5554	chan = l2cap_get_chan_by_dcid(conn, cid);
5555	if (!chan)
5556		return -EBADSLT;
5557
5558	max_credits = LE_FLOWCTL_MAX_CREDITS - chan->tx_credits;
5559	if (credits > max_credits) {
5560		BT_ERR("LE credits overflow");
5561		l2cap_send_disconn_req(chan, ECONNRESET);
5562		l2cap_chan_unlock(chan);
5563
5564		/* Return 0 so that we don't trigger an unnecessary
5565		 * command reject packet.
5566		 */
5567		return 0;
5568	}
5569
5570	chan->tx_credits += credits;
5571
5572	while (chan->tx_credits && !skb_queue_empty(&chan->tx_q)) {
5573		l2cap_do_send(chan, skb_dequeue(&chan->tx_q));
5574		chan->tx_credits--;
5575	}
5576
5577	if (chan->tx_credits)
5578		chan->ops->resume(chan);
5579
5580	l2cap_chan_unlock(chan);
5581
5582	return 0;
5583}
5584
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5585static inline int l2cap_le_command_rej(struct l2cap_conn *conn,
5586				       struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5587				       u8 *data)
5588{
5589	struct l2cap_cmd_rej_unk *rej = (struct l2cap_cmd_rej_unk *) data;
5590	struct l2cap_chan *chan;
5591
5592	if (cmd_len < sizeof(*rej))
5593		return -EPROTO;
5594
5595	mutex_lock(&conn->chan_lock);
5596
5597	chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
5598	if (!chan)
5599		goto done;
5600
5601	l2cap_chan_lock(chan);
5602	l2cap_chan_del(chan, ECONNREFUSED);
5603	l2cap_chan_unlock(chan);
5604
5605done:
5606	mutex_unlock(&conn->chan_lock);
5607	return 0;
5608}
5609
5610static inline int l2cap_le_sig_cmd(struct l2cap_conn *conn,
5611				   struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5612				   u8 *data)
5613{
5614	int err = 0;
5615
5616	switch (cmd->code) {
5617	case L2CAP_COMMAND_REJ:
5618		l2cap_le_command_rej(conn, cmd, cmd_len, data);
5619		break;
5620
5621	case L2CAP_CONN_PARAM_UPDATE_REQ:
5622		err = l2cap_conn_param_update_req(conn, cmd, cmd_len, data);
5623		break;
5624
5625	case L2CAP_CONN_PARAM_UPDATE_RSP:
5626		break;
5627
5628	case L2CAP_LE_CONN_RSP:
5629		l2cap_le_connect_rsp(conn, cmd, cmd_len, data);
5630		break;
5631
5632	case L2CAP_LE_CONN_REQ:
5633		err = l2cap_le_connect_req(conn, cmd, cmd_len, data);
5634		break;
5635
5636	case L2CAP_LE_CREDITS:
5637		err = l2cap_le_credits(conn, cmd, cmd_len, data);
5638		break;
5639
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5640	case L2CAP_DISCONN_REQ:
5641		err = l2cap_disconnect_req(conn, cmd, cmd_len, data);
5642		break;
5643
5644	case L2CAP_DISCONN_RSP:
5645		l2cap_disconnect_rsp(conn, cmd, cmd_len, data);
5646		break;
5647
5648	default:
5649		BT_ERR("Unknown LE signaling command 0x%2.2x", cmd->code);
5650		err = -EINVAL;
5651		break;
5652	}
5653
5654	return err;
5655}
5656
5657static inline void l2cap_le_sig_channel(struct l2cap_conn *conn,
5658					struct sk_buff *skb)
5659{
5660	struct hci_conn *hcon = conn->hcon;
5661	struct l2cap_cmd_hdr *cmd;
5662	u16 len;
5663	int err;
5664
5665	if (hcon->type != LE_LINK)
5666		goto drop;
5667
5668	if (skb->len < L2CAP_CMD_HDR_SIZE)
5669		goto drop;
5670
5671	cmd = (void *) skb->data;
5672	skb_pull(skb, L2CAP_CMD_HDR_SIZE);
5673
5674	len = le16_to_cpu(cmd->len);
5675
5676	BT_DBG("code 0x%2.2x len %d id 0x%2.2x", cmd->code, len, cmd->ident);
5677
5678	if (len != skb->len || !cmd->ident) {
5679		BT_DBG("corrupted command");
5680		goto drop;
5681	}
5682
5683	err = l2cap_le_sig_cmd(conn, cmd, len, skb->data);
5684	if (err) {
5685		struct l2cap_cmd_rej_unk rej;
5686
5687		BT_ERR("Wrong link type (%d)", err);
5688
5689		rej.reason = cpu_to_le16(L2CAP_REJ_NOT_UNDERSTOOD);
5690		l2cap_send_cmd(conn, cmd->ident, L2CAP_COMMAND_REJ,
5691			       sizeof(rej), &rej);
5692	}
5693
5694drop:
5695	kfree_skb(skb);
5696}
5697
5698static inline void l2cap_sig_channel(struct l2cap_conn *conn,
5699				     struct sk_buff *skb)
5700{
5701	struct hci_conn *hcon = conn->hcon;
5702	u8 *data = skb->data;
5703	int len = skb->len;
5704	struct l2cap_cmd_hdr cmd;
5705	int err;
5706
5707	l2cap_raw_recv(conn, skb);
5708
5709	if (hcon->type != ACL_LINK)
5710		goto drop;
5711
5712	while (len >= L2CAP_CMD_HDR_SIZE) {
5713		u16 cmd_len;
5714		memcpy(&cmd, data, L2CAP_CMD_HDR_SIZE);
5715		data += L2CAP_CMD_HDR_SIZE;
5716		len  -= L2CAP_CMD_HDR_SIZE;
5717
5718		cmd_len = le16_to_cpu(cmd.len);
5719
5720		BT_DBG("code 0x%2.2x len %d id 0x%2.2x", cmd.code, cmd_len,
5721		       cmd.ident);
5722
5723		if (cmd_len > len || !cmd.ident) {
5724			BT_DBG("corrupted command");
5725			break;
5726		}
5727
5728		err = l2cap_bredr_sig_cmd(conn, &cmd, cmd_len, data);
5729		if (err) {
5730			struct l2cap_cmd_rej_unk rej;
5731
5732			BT_ERR("Wrong link type (%d)", err);
5733
5734			rej.reason = cpu_to_le16(L2CAP_REJ_NOT_UNDERSTOOD);
5735			l2cap_send_cmd(conn, cmd.ident, L2CAP_COMMAND_REJ,
5736				       sizeof(rej), &rej);
5737		}
5738
5739		data += cmd_len;
5740		len  -= cmd_len;
5741	}
5742
5743drop:
5744	kfree_skb(skb);
5745}
5746
5747static int l2cap_check_fcs(struct l2cap_chan *chan,  struct sk_buff *skb)
5748{
5749	u16 our_fcs, rcv_fcs;
5750	int hdr_size;
5751
5752	if (test_bit(FLAG_EXT_CTRL, &chan->flags))
5753		hdr_size = L2CAP_EXT_HDR_SIZE;
5754	else
5755		hdr_size = L2CAP_ENH_HDR_SIZE;
5756
5757	if (chan->fcs == L2CAP_FCS_CRC16) {
5758		skb_trim(skb, skb->len - L2CAP_FCS_SIZE);
5759		rcv_fcs = get_unaligned_le16(skb->data + skb->len);
5760		our_fcs = crc16(0, skb->data - hdr_size, skb->len + hdr_size);
5761
5762		if (our_fcs != rcv_fcs)
5763			return -EBADMSG;
5764	}
5765	return 0;
5766}
5767
5768static void l2cap_send_i_or_rr_or_rnr(struct l2cap_chan *chan)
5769{
5770	struct l2cap_ctrl control;
5771
5772	BT_DBG("chan %p", chan);
5773
5774	memset(&control, 0, sizeof(control));
5775	control.sframe = 1;
5776	control.final = 1;
5777	control.reqseq = chan->buffer_seq;
5778	set_bit(CONN_SEND_FBIT, &chan->conn_state);
5779
5780	if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
5781		control.super = L2CAP_SUPER_RNR;
5782		l2cap_send_sframe(chan, &control);
5783	}
5784
5785	if (test_and_clear_bit(CONN_REMOTE_BUSY, &chan->conn_state) &&
5786	    chan->unacked_frames > 0)
5787		__set_retrans_timer(chan);
5788
5789	/* Send pending iframes */
5790	l2cap_ertm_send(chan);
5791
5792	if (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state) &&
5793	    test_bit(CONN_SEND_FBIT, &chan->conn_state)) {
5794		/* F-bit wasn't sent in an s-frame or i-frame yet, so
5795		 * send it now.
5796		 */
5797		control.super = L2CAP_SUPER_RR;
5798		l2cap_send_sframe(chan, &control);
5799	}
5800}
5801
5802static void append_skb_frag(struct sk_buff *skb, struct sk_buff *new_frag,
5803			    struct sk_buff **last_frag)
5804{
5805	/* skb->len reflects data in skb as well as all fragments
5806	 * skb->data_len reflects only data in fragments
5807	 */
5808	if (!skb_has_frag_list(skb))
5809		skb_shinfo(skb)->frag_list = new_frag;
5810
5811	new_frag->next = NULL;
5812
5813	(*last_frag)->next = new_frag;
5814	*last_frag = new_frag;
5815
5816	skb->len += new_frag->len;
5817	skb->data_len += new_frag->len;
5818	skb->truesize += new_frag->truesize;
5819}
5820
5821static int l2cap_reassemble_sdu(struct l2cap_chan *chan, struct sk_buff *skb,
5822				struct l2cap_ctrl *control)
5823{
5824	int err = -EINVAL;
5825
5826	switch (control->sar) {
5827	case L2CAP_SAR_UNSEGMENTED:
5828		if (chan->sdu)
5829			break;
5830
5831		err = chan->ops->recv(chan, skb);
5832		break;
5833
5834	case L2CAP_SAR_START:
5835		if (chan->sdu)
5836			break;
5837
 
 
 
5838		chan->sdu_len = get_unaligned_le16(skb->data);
5839		skb_pull(skb, L2CAP_SDULEN_SIZE);
5840
5841		if (chan->sdu_len > chan->imtu) {
5842			err = -EMSGSIZE;
5843			break;
5844		}
5845
5846		if (skb->len >= chan->sdu_len)
5847			break;
5848
5849		chan->sdu = skb;
5850		chan->sdu_last_frag = skb;
5851
5852		skb = NULL;
5853		err = 0;
5854		break;
5855
5856	case L2CAP_SAR_CONTINUE:
5857		if (!chan->sdu)
5858			break;
5859
5860		append_skb_frag(chan->sdu, skb,
5861				&chan->sdu_last_frag);
5862		skb = NULL;
5863
5864		if (chan->sdu->len >= chan->sdu_len)
5865			break;
5866
5867		err = 0;
5868		break;
5869
5870	case L2CAP_SAR_END:
5871		if (!chan->sdu)
5872			break;
5873
5874		append_skb_frag(chan->sdu, skb,
5875				&chan->sdu_last_frag);
5876		skb = NULL;
5877
5878		if (chan->sdu->len != chan->sdu_len)
5879			break;
5880
5881		err = chan->ops->recv(chan, chan->sdu);
5882
5883		if (!err) {
5884			/* Reassembly complete */
5885			chan->sdu = NULL;
5886			chan->sdu_last_frag = NULL;
5887			chan->sdu_len = 0;
5888		}
5889		break;
5890	}
5891
5892	if (err) {
5893		kfree_skb(skb);
5894		kfree_skb(chan->sdu);
5895		chan->sdu = NULL;
5896		chan->sdu_last_frag = NULL;
5897		chan->sdu_len = 0;
5898	}
5899
5900	return err;
5901}
5902
5903static int l2cap_resegment(struct l2cap_chan *chan)
5904{
5905	/* Placeholder */
5906	return 0;
5907}
5908
5909void l2cap_chan_busy(struct l2cap_chan *chan, int busy)
5910{
5911	u8 event;
5912
5913	if (chan->mode != L2CAP_MODE_ERTM)
5914		return;
5915
5916	event = busy ? L2CAP_EV_LOCAL_BUSY_DETECTED : L2CAP_EV_LOCAL_BUSY_CLEAR;
5917	l2cap_tx(chan, NULL, NULL, event);
5918}
5919
5920static int l2cap_rx_queued_iframes(struct l2cap_chan *chan)
5921{
5922	int err = 0;
5923	/* Pass sequential frames to l2cap_reassemble_sdu()
5924	 * until a gap is encountered.
5925	 */
5926
5927	BT_DBG("chan %p", chan);
5928
5929	while (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
5930		struct sk_buff *skb;
5931		BT_DBG("Searching for skb with txseq %d (queue len %d)",
5932		       chan->buffer_seq, skb_queue_len(&chan->srej_q));
5933
5934		skb = l2cap_ertm_seq_in_queue(&chan->srej_q, chan->buffer_seq);
5935
5936		if (!skb)
5937			break;
5938
5939		skb_unlink(skb, &chan->srej_q);
5940		chan->buffer_seq = __next_seq(chan, chan->buffer_seq);
5941		err = l2cap_reassemble_sdu(chan, skb, &bt_cb(skb)->l2cap);
5942		if (err)
5943			break;
5944	}
5945
5946	if (skb_queue_empty(&chan->srej_q)) {
5947		chan->rx_state = L2CAP_RX_STATE_RECV;
5948		l2cap_send_ack(chan);
5949	}
5950
5951	return err;
5952}
5953
5954static void l2cap_handle_srej(struct l2cap_chan *chan,
5955			      struct l2cap_ctrl *control)
5956{
5957	struct sk_buff *skb;
5958
5959	BT_DBG("chan %p, control %p", chan, control);
5960
5961	if (control->reqseq == chan->next_tx_seq) {
5962		BT_DBG("Invalid reqseq %d, disconnecting", control->reqseq);
5963		l2cap_send_disconn_req(chan, ECONNRESET);
5964		return;
5965	}
5966
5967	skb = l2cap_ertm_seq_in_queue(&chan->tx_q, control->reqseq);
5968
5969	if (skb == NULL) {
5970		BT_DBG("Seq %d not available for retransmission",
5971		       control->reqseq);
5972		return;
5973	}
5974
5975	if (chan->max_tx != 0 && bt_cb(skb)->l2cap.retries >= chan->max_tx) {
5976		BT_DBG("Retry limit exceeded (%d)", chan->max_tx);
5977		l2cap_send_disconn_req(chan, ECONNRESET);
5978		return;
5979	}
5980
5981	clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
5982
5983	if (control->poll) {
5984		l2cap_pass_to_tx(chan, control);
5985
5986		set_bit(CONN_SEND_FBIT, &chan->conn_state);
5987		l2cap_retransmit(chan, control);
5988		l2cap_ertm_send(chan);
5989
5990		if (chan->tx_state == L2CAP_TX_STATE_WAIT_F) {
5991			set_bit(CONN_SREJ_ACT, &chan->conn_state);
5992			chan->srej_save_reqseq = control->reqseq;
5993		}
5994	} else {
5995		l2cap_pass_to_tx_fbit(chan, control);
5996
5997		if (control->final) {
5998			if (chan->srej_save_reqseq != control->reqseq ||
5999			    !test_and_clear_bit(CONN_SREJ_ACT,
6000						&chan->conn_state))
6001				l2cap_retransmit(chan, control);
6002		} else {
6003			l2cap_retransmit(chan, control);
6004			if (chan->tx_state == L2CAP_TX_STATE_WAIT_F) {
6005				set_bit(CONN_SREJ_ACT, &chan->conn_state);
6006				chan->srej_save_reqseq = control->reqseq;
6007			}
6008		}
6009	}
6010}
6011
6012static void l2cap_handle_rej(struct l2cap_chan *chan,
6013			     struct l2cap_ctrl *control)
6014{
6015	struct sk_buff *skb;
6016
6017	BT_DBG("chan %p, control %p", chan, control);
6018
6019	if (control->reqseq == chan->next_tx_seq) {
6020		BT_DBG("Invalid reqseq %d, disconnecting", control->reqseq);
6021		l2cap_send_disconn_req(chan, ECONNRESET);
6022		return;
6023	}
6024
6025	skb = l2cap_ertm_seq_in_queue(&chan->tx_q, control->reqseq);
6026
6027	if (chan->max_tx && skb &&
6028	    bt_cb(skb)->l2cap.retries >= chan->max_tx) {
6029		BT_DBG("Retry limit exceeded (%d)", chan->max_tx);
6030		l2cap_send_disconn_req(chan, ECONNRESET);
6031		return;
6032	}
6033
6034	clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6035
6036	l2cap_pass_to_tx(chan, control);
6037
6038	if (control->final) {
6039		if (!test_and_clear_bit(CONN_REJ_ACT, &chan->conn_state))
6040			l2cap_retransmit_all(chan, control);
6041	} else {
6042		l2cap_retransmit_all(chan, control);
6043		l2cap_ertm_send(chan);
6044		if (chan->tx_state == L2CAP_TX_STATE_WAIT_F)
6045			set_bit(CONN_REJ_ACT, &chan->conn_state);
6046	}
6047}
6048
6049static u8 l2cap_classify_txseq(struct l2cap_chan *chan, u16 txseq)
6050{
6051	BT_DBG("chan %p, txseq %d", chan, txseq);
6052
6053	BT_DBG("last_acked_seq %d, expected_tx_seq %d", chan->last_acked_seq,
6054	       chan->expected_tx_seq);
6055
6056	if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) {
6057		if (__seq_offset(chan, txseq, chan->last_acked_seq) >=
6058		    chan->tx_win) {
6059			/* See notes below regarding "double poll" and
6060			 * invalid packets.
6061			 */
6062			if (chan->tx_win <= ((chan->tx_win_max + 1) >> 1)) {
6063				BT_DBG("Invalid/Ignore - after SREJ");
6064				return L2CAP_TXSEQ_INVALID_IGNORE;
6065			} else {
6066				BT_DBG("Invalid - in window after SREJ sent");
6067				return L2CAP_TXSEQ_INVALID;
6068			}
6069		}
6070
6071		if (chan->srej_list.head == txseq) {
6072			BT_DBG("Expected SREJ");
6073			return L2CAP_TXSEQ_EXPECTED_SREJ;
6074		}
6075
6076		if (l2cap_ertm_seq_in_queue(&chan->srej_q, txseq)) {
6077			BT_DBG("Duplicate SREJ - txseq already stored");
6078			return L2CAP_TXSEQ_DUPLICATE_SREJ;
6079		}
6080
6081		if (l2cap_seq_list_contains(&chan->srej_list, txseq)) {
6082			BT_DBG("Unexpected SREJ - not requested");
6083			return L2CAP_TXSEQ_UNEXPECTED_SREJ;
6084		}
6085	}
6086
6087	if (chan->expected_tx_seq == txseq) {
6088		if (__seq_offset(chan, txseq, chan->last_acked_seq) >=
6089		    chan->tx_win) {
6090			BT_DBG("Invalid - txseq outside tx window");
6091			return L2CAP_TXSEQ_INVALID;
6092		} else {
6093			BT_DBG("Expected");
6094			return L2CAP_TXSEQ_EXPECTED;
6095		}
6096	}
6097
6098	if (__seq_offset(chan, txseq, chan->last_acked_seq) <
6099	    __seq_offset(chan, chan->expected_tx_seq, chan->last_acked_seq)) {
6100		BT_DBG("Duplicate - expected_tx_seq later than txseq");
6101		return L2CAP_TXSEQ_DUPLICATE;
6102	}
6103
6104	if (__seq_offset(chan, txseq, chan->last_acked_seq) >= chan->tx_win) {
6105		/* A source of invalid packets is a "double poll" condition,
6106		 * where delays cause us to send multiple poll packets.  If
6107		 * the remote stack receives and processes both polls,
6108		 * sequence numbers can wrap around in such a way that a
6109		 * resent frame has a sequence number that looks like new data
6110		 * with a sequence gap.  This would trigger an erroneous SREJ
6111		 * request.
6112		 *
6113		 * Fortunately, this is impossible with a tx window that's
6114		 * less than half of the maximum sequence number, which allows
6115		 * invalid frames to be safely ignored.
6116		 *
6117		 * With tx window sizes greater than half of the tx window
6118		 * maximum, the frame is invalid and cannot be ignored.  This
6119		 * causes a disconnect.
6120		 */
6121
6122		if (chan->tx_win <= ((chan->tx_win_max + 1) >> 1)) {
6123			BT_DBG("Invalid/Ignore - txseq outside tx window");
6124			return L2CAP_TXSEQ_INVALID_IGNORE;
6125		} else {
6126			BT_DBG("Invalid - txseq outside tx window");
6127			return L2CAP_TXSEQ_INVALID;
6128		}
6129	} else {
6130		BT_DBG("Unexpected - txseq indicates missing frames");
6131		return L2CAP_TXSEQ_UNEXPECTED;
6132	}
6133}
6134
6135static int l2cap_rx_state_recv(struct l2cap_chan *chan,
6136			       struct l2cap_ctrl *control,
6137			       struct sk_buff *skb, u8 event)
6138{
6139	int err = 0;
6140	bool skb_in_use = false;
6141
6142	BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
6143	       event);
6144
6145	switch (event) {
6146	case L2CAP_EV_RECV_IFRAME:
6147		switch (l2cap_classify_txseq(chan, control->txseq)) {
6148		case L2CAP_TXSEQ_EXPECTED:
6149			l2cap_pass_to_tx(chan, control);
6150
6151			if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
6152				BT_DBG("Busy, discarding expected seq %d",
6153				       control->txseq);
6154				break;
6155			}
6156
6157			chan->expected_tx_seq = __next_seq(chan,
6158							   control->txseq);
6159
6160			chan->buffer_seq = chan->expected_tx_seq;
6161			skb_in_use = true;
6162
6163			err = l2cap_reassemble_sdu(chan, skb, control);
6164			if (err)
6165				break;
6166
6167			if (control->final) {
6168				if (!test_and_clear_bit(CONN_REJ_ACT,
6169							&chan->conn_state)) {
6170					control->final = 0;
6171					l2cap_retransmit_all(chan, control);
6172					l2cap_ertm_send(chan);
6173				}
6174			}
6175
6176			if (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state))
6177				l2cap_send_ack(chan);
6178			break;
6179		case L2CAP_TXSEQ_UNEXPECTED:
6180			l2cap_pass_to_tx(chan, control);
6181
6182			/* Can't issue SREJ frames in the local busy state.
6183			 * Drop this frame, it will be seen as missing
6184			 * when local busy is exited.
6185			 */
6186			if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
6187				BT_DBG("Busy, discarding unexpected seq %d",
6188				       control->txseq);
6189				break;
6190			}
6191
6192			/* There was a gap in the sequence, so an SREJ
6193			 * must be sent for each missing frame.  The
6194			 * current frame is stored for later use.
6195			 */
6196			skb_queue_tail(&chan->srej_q, skb);
6197			skb_in_use = true;
6198			BT_DBG("Queued %p (queue len %d)", skb,
6199			       skb_queue_len(&chan->srej_q));
6200
6201			clear_bit(CONN_SREJ_ACT, &chan->conn_state);
6202			l2cap_seq_list_clear(&chan->srej_list);
6203			l2cap_send_srej(chan, control->txseq);
6204
6205			chan->rx_state = L2CAP_RX_STATE_SREJ_SENT;
6206			break;
6207		case L2CAP_TXSEQ_DUPLICATE:
6208			l2cap_pass_to_tx(chan, control);
6209			break;
6210		case L2CAP_TXSEQ_INVALID_IGNORE:
6211			break;
6212		case L2CAP_TXSEQ_INVALID:
6213		default:
6214			l2cap_send_disconn_req(chan, ECONNRESET);
6215			break;
6216		}
6217		break;
6218	case L2CAP_EV_RECV_RR:
6219		l2cap_pass_to_tx(chan, control);
6220		if (control->final) {
6221			clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6222
6223			if (!test_and_clear_bit(CONN_REJ_ACT, &chan->conn_state) &&
6224			    !__chan_is_moving(chan)) {
6225				control->final = 0;
6226				l2cap_retransmit_all(chan, control);
6227			}
6228
6229			l2cap_ertm_send(chan);
6230		} else if (control->poll) {
6231			l2cap_send_i_or_rr_or_rnr(chan);
6232		} else {
6233			if (test_and_clear_bit(CONN_REMOTE_BUSY,
6234					       &chan->conn_state) &&
6235			    chan->unacked_frames)
6236				__set_retrans_timer(chan);
6237
6238			l2cap_ertm_send(chan);
6239		}
6240		break;
6241	case L2CAP_EV_RECV_RNR:
6242		set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6243		l2cap_pass_to_tx(chan, control);
6244		if (control && control->poll) {
6245			set_bit(CONN_SEND_FBIT, &chan->conn_state);
6246			l2cap_send_rr_or_rnr(chan, 0);
6247		}
6248		__clear_retrans_timer(chan);
6249		l2cap_seq_list_clear(&chan->retrans_list);
6250		break;
6251	case L2CAP_EV_RECV_REJ:
6252		l2cap_handle_rej(chan, control);
6253		break;
6254	case L2CAP_EV_RECV_SREJ:
6255		l2cap_handle_srej(chan, control);
6256		break;
6257	default:
6258		break;
6259	}
6260
6261	if (skb && !skb_in_use) {
6262		BT_DBG("Freeing %p", skb);
6263		kfree_skb(skb);
6264	}
6265
6266	return err;
6267}
6268
6269static int l2cap_rx_state_srej_sent(struct l2cap_chan *chan,
6270				    struct l2cap_ctrl *control,
6271				    struct sk_buff *skb, u8 event)
6272{
6273	int err = 0;
6274	u16 txseq = control->txseq;
6275	bool skb_in_use = false;
6276
6277	BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
6278	       event);
6279
6280	switch (event) {
6281	case L2CAP_EV_RECV_IFRAME:
6282		switch (l2cap_classify_txseq(chan, txseq)) {
6283		case L2CAP_TXSEQ_EXPECTED:
6284			/* Keep frame for reassembly later */
6285			l2cap_pass_to_tx(chan, control);
6286			skb_queue_tail(&chan->srej_q, skb);
6287			skb_in_use = true;
6288			BT_DBG("Queued %p (queue len %d)", skb,
6289			       skb_queue_len(&chan->srej_q));
6290
6291			chan->expected_tx_seq = __next_seq(chan, txseq);
6292			break;
6293		case L2CAP_TXSEQ_EXPECTED_SREJ:
6294			l2cap_seq_list_pop(&chan->srej_list);
6295
6296			l2cap_pass_to_tx(chan, control);
6297			skb_queue_tail(&chan->srej_q, skb);
6298			skb_in_use = true;
6299			BT_DBG("Queued %p (queue len %d)", skb,
6300			       skb_queue_len(&chan->srej_q));
6301
6302			err = l2cap_rx_queued_iframes(chan);
6303			if (err)
6304				break;
6305
6306			break;
6307		case L2CAP_TXSEQ_UNEXPECTED:
6308			/* Got a frame that can't be reassembled yet.
6309			 * Save it for later, and send SREJs to cover
6310			 * the missing frames.
6311			 */
6312			skb_queue_tail(&chan->srej_q, skb);
6313			skb_in_use = true;
6314			BT_DBG("Queued %p (queue len %d)", skb,
6315			       skb_queue_len(&chan->srej_q));
6316
6317			l2cap_pass_to_tx(chan, control);
6318			l2cap_send_srej(chan, control->txseq);
6319			break;
6320		case L2CAP_TXSEQ_UNEXPECTED_SREJ:
6321			/* This frame was requested with an SREJ, but
6322			 * some expected retransmitted frames are
6323			 * missing.  Request retransmission of missing
6324			 * SREJ'd frames.
6325			 */
6326			skb_queue_tail(&chan->srej_q, skb);
6327			skb_in_use = true;
6328			BT_DBG("Queued %p (queue len %d)", skb,
6329			       skb_queue_len(&chan->srej_q));
6330
6331			l2cap_pass_to_tx(chan, control);
6332			l2cap_send_srej_list(chan, control->txseq);
6333			break;
6334		case L2CAP_TXSEQ_DUPLICATE_SREJ:
6335			/* We've already queued this frame.  Drop this copy. */
6336			l2cap_pass_to_tx(chan, control);
6337			break;
6338		case L2CAP_TXSEQ_DUPLICATE:
6339			/* Expecting a later sequence number, so this frame
6340			 * was already received.  Ignore it completely.
6341			 */
6342			break;
6343		case L2CAP_TXSEQ_INVALID_IGNORE:
6344			break;
6345		case L2CAP_TXSEQ_INVALID:
6346		default:
6347			l2cap_send_disconn_req(chan, ECONNRESET);
6348			break;
6349		}
6350		break;
6351	case L2CAP_EV_RECV_RR:
6352		l2cap_pass_to_tx(chan, control);
6353		if (control->final) {
6354			clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6355
6356			if (!test_and_clear_bit(CONN_REJ_ACT,
6357						&chan->conn_state)) {
6358				control->final = 0;
6359				l2cap_retransmit_all(chan, control);
6360			}
6361
6362			l2cap_ertm_send(chan);
6363		} else if (control->poll) {
6364			if (test_and_clear_bit(CONN_REMOTE_BUSY,
6365					       &chan->conn_state) &&
6366			    chan->unacked_frames) {
6367				__set_retrans_timer(chan);
6368			}
6369
6370			set_bit(CONN_SEND_FBIT, &chan->conn_state);
6371			l2cap_send_srej_tail(chan);
6372		} else {
6373			if (test_and_clear_bit(CONN_REMOTE_BUSY,
6374					       &chan->conn_state) &&
6375			    chan->unacked_frames)
6376				__set_retrans_timer(chan);
6377
6378			l2cap_send_ack(chan);
6379		}
6380		break;
6381	case L2CAP_EV_RECV_RNR:
6382		set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6383		l2cap_pass_to_tx(chan, control);
6384		if (control->poll) {
6385			l2cap_send_srej_tail(chan);
6386		} else {
6387			struct l2cap_ctrl rr_control;
6388			memset(&rr_control, 0, sizeof(rr_control));
6389			rr_control.sframe = 1;
6390			rr_control.super = L2CAP_SUPER_RR;
6391			rr_control.reqseq = chan->buffer_seq;
6392			l2cap_send_sframe(chan, &rr_control);
6393		}
6394
6395		break;
6396	case L2CAP_EV_RECV_REJ:
6397		l2cap_handle_rej(chan, control);
6398		break;
6399	case L2CAP_EV_RECV_SREJ:
6400		l2cap_handle_srej(chan, control);
6401		break;
6402	}
6403
6404	if (skb && !skb_in_use) {
6405		BT_DBG("Freeing %p", skb);
6406		kfree_skb(skb);
6407	}
6408
6409	return err;
6410}
6411
6412static int l2cap_finish_move(struct l2cap_chan *chan)
6413{
6414	BT_DBG("chan %p", chan);
6415
6416	chan->rx_state = L2CAP_RX_STATE_RECV;
6417
6418	if (chan->hs_hcon)
6419		chan->conn->mtu = chan->hs_hcon->hdev->block_mtu;
6420	else
6421		chan->conn->mtu = chan->conn->hcon->hdev->acl_mtu;
6422
6423	return l2cap_resegment(chan);
6424}
6425
6426static int l2cap_rx_state_wait_p(struct l2cap_chan *chan,
6427				 struct l2cap_ctrl *control,
6428				 struct sk_buff *skb, u8 event)
6429{
6430	int err;
6431
6432	BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
6433	       event);
6434
6435	if (!control->poll)
6436		return -EPROTO;
6437
6438	l2cap_process_reqseq(chan, control->reqseq);
6439
6440	if (!skb_queue_empty(&chan->tx_q))
6441		chan->tx_send_head = skb_peek(&chan->tx_q);
6442	else
6443		chan->tx_send_head = NULL;
6444
6445	/* Rewind next_tx_seq to the point expected
6446	 * by the receiver.
6447	 */
6448	chan->next_tx_seq = control->reqseq;
6449	chan->unacked_frames = 0;
6450
6451	err = l2cap_finish_move(chan);
6452	if (err)
6453		return err;
6454
6455	set_bit(CONN_SEND_FBIT, &chan->conn_state);
6456	l2cap_send_i_or_rr_or_rnr(chan);
6457
6458	if (event == L2CAP_EV_RECV_IFRAME)
6459		return -EPROTO;
6460
6461	return l2cap_rx_state_recv(chan, control, NULL, event);
6462}
6463
6464static int l2cap_rx_state_wait_f(struct l2cap_chan *chan,
6465				 struct l2cap_ctrl *control,
6466				 struct sk_buff *skb, u8 event)
6467{
6468	int err;
6469
6470	if (!control->final)
6471		return -EPROTO;
6472
6473	clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6474
6475	chan->rx_state = L2CAP_RX_STATE_RECV;
6476	l2cap_process_reqseq(chan, control->reqseq);
6477
6478	if (!skb_queue_empty(&chan->tx_q))
6479		chan->tx_send_head = skb_peek(&chan->tx_q);
6480	else
6481		chan->tx_send_head = NULL;
6482
6483	/* Rewind next_tx_seq to the point expected
6484	 * by the receiver.
6485	 */
6486	chan->next_tx_seq = control->reqseq;
6487	chan->unacked_frames = 0;
6488
6489	if (chan->hs_hcon)
6490		chan->conn->mtu = chan->hs_hcon->hdev->block_mtu;
6491	else
6492		chan->conn->mtu = chan->conn->hcon->hdev->acl_mtu;
6493
6494	err = l2cap_resegment(chan);
6495
6496	if (!err)
6497		err = l2cap_rx_state_recv(chan, control, skb, event);
6498
6499	return err;
6500}
6501
6502static bool __valid_reqseq(struct l2cap_chan *chan, u16 reqseq)
6503{
6504	/* Make sure reqseq is for a packet that has been sent but not acked */
6505	u16 unacked;
6506
6507	unacked = __seq_offset(chan, chan->next_tx_seq, chan->expected_ack_seq);
6508	return __seq_offset(chan, chan->next_tx_seq, reqseq) <= unacked;
6509}
6510
6511static int l2cap_rx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
6512		    struct sk_buff *skb, u8 event)
6513{
6514	int err = 0;
6515
6516	BT_DBG("chan %p, control %p, skb %p, event %d, state %d", chan,
6517	       control, skb, event, chan->rx_state);
6518
6519	if (__valid_reqseq(chan, control->reqseq)) {
6520		switch (chan->rx_state) {
6521		case L2CAP_RX_STATE_RECV:
6522			err = l2cap_rx_state_recv(chan, control, skb, event);
6523			break;
6524		case L2CAP_RX_STATE_SREJ_SENT:
6525			err = l2cap_rx_state_srej_sent(chan, control, skb,
6526						       event);
6527			break;
6528		case L2CAP_RX_STATE_WAIT_P:
6529			err = l2cap_rx_state_wait_p(chan, control, skb, event);
6530			break;
6531		case L2CAP_RX_STATE_WAIT_F:
6532			err = l2cap_rx_state_wait_f(chan, control, skb, event);
6533			break;
6534		default:
6535			/* shut it down */
6536			break;
6537		}
6538	} else {
6539		BT_DBG("Invalid reqseq %d (next_tx_seq %d, expected_ack_seq %d",
6540		       control->reqseq, chan->next_tx_seq,
6541		       chan->expected_ack_seq);
6542		l2cap_send_disconn_req(chan, ECONNRESET);
6543	}
6544
6545	return err;
6546}
6547
6548static int l2cap_stream_rx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
6549			   struct sk_buff *skb)
6550{
6551	BT_DBG("chan %p, control %p, skb %p, state %d", chan, control, skb,
6552	       chan->rx_state);
6553
6554	if (l2cap_classify_txseq(chan, control->txseq) ==
6555	    L2CAP_TXSEQ_EXPECTED) {
6556		l2cap_pass_to_tx(chan, control);
6557
6558		BT_DBG("buffer_seq %d->%d", chan->buffer_seq,
6559		       __next_seq(chan, chan->buffer_seq));
6560
6561		chan->buffer_seq = __next_seq(chan, chan->buffer_seq);
6562
6563		l2cap_reassemble_sdu(chan, skb, control);
6564	} else {
6565		if (chan->sdu) {
6566			kfree_skb(chan->sdu);
6567			chan->sdu = NULL;
6568		}
6569		chan->sdu_last_frag = NULL;
6570		chan->sdu_len = 0;
6571
6572		if (skb) {
6573			BT_DBG("Freeing %p", skb);
6574			kfree_skb(skb);
6575		}
6576	}
6577
6578	chan->last_acked_seq = control->txseq;
6579	chan->expected_tx_seq = __next_seq(chan, control->txseq);
6580
6581	return 0;
6582}
6583
6584static int l2cap_data_rcv(struct l2cap_chan *chan, struct sk_buff *skb)
6585{
6586	struct l2cap_ctrl *control = &bt_cb(skb)->l2cap;
6587	u16 len;
6588	u8 event;
6589
6590	__unpack_control(chan, skb);
6591
6592	len = skb->len;
6593
6594	/*
6595	 * We can just drop the corrupted I-frame here.
6596	 * Receiver will miss it and start proper recovery
6597	 * procedures and ask for retransmission.
6598	 */
6599	if (l2cap_check_fcs(chan, skb))
6600		goto drop;
6601
6602	if (!control->sframe && control->sar == L2CAP_SAR_START)
6603		len -= L2CAP_SDULEN_SIZE;
6604
6605	if (chan->fcs == L2CAP_FCS_CRC16)
6606		len -= L2CAP_FCS_SIZE;
6607
6608	if (len > chan->mps) {
6609		l2cap_send_disconn_req(chan, ECONNRESET);
6610		goto drop;
6611	}
6612
 
 
 
 
 
6613	if (!control->sframe) {
6614		int err;
6615
6616		BT_DBG("iframe sar %d, reqseq %d, final %d, txseq %d",
6617		       control->sar, control->reqseq, control->final,
6618		       control->txseq);
6619
6620		/* Validate F-bit - F=0 always valid, F=1 only
6621		 * valid in TX WAIT_F
6622		 */
6623		if (control->final && chan->tx_state != L2CAP_TX_STATE_WAIT_F)
6624			goto drop;
6625
6626		if (chan->mode != L2CAP_MODE_STREAMING) {
6627			event = L2CAP_EV_RECV_IFRAME;
6628			err = l2cap_rx(chan, control, skb, event);
6629		} else {
6630			err = l2cap_stream_rx(chan, control, skb);
6631		}
6632
6633		if (err)
6634			l2cap_send_disconn_req(chan, ECONNRESET);
6635	} else {
6636		const u8 rx_func_to_event[4] = {
6637			L2CAP_EV_RECV_RR, L2CAP_EV_RECV_REJ,
6638			L2CAP_EV_RECV_RNR, L2CAP_EV_RECV_SREJ
6639		};
6640
6641		/* Only I-frames are expected in streaming mode */
6642		if (chan->mode == L2CAP_MODE_STREAMING)
6643			goto drop;
6644
6645		BT_DBG("sframe reqseq %d, final %d, poll %d, super %d",
6646		       control->reqseq, control->final, control->poll,
6647		       control->super);
6648
6649		if (len != 0) {
6650			BT_ERR("Trailing bytes: %d in sframe", len);
6651			l2cap_send_disconn_req(chan, ECONNRESET);
6652			goto drop;
6653		}
6654
6655		/* Validate F and P bits */
6656		if (control->final && (control->poll ||
6657				       chan->tx_state != L2CAP_TX_STATE_WAIT_F))
6658			goto drop;
6659
6660		event = rx_func_to_event[control->super];
6661		if (l2cap_rx(chan, control, skb, event))
6662			l2cap_send_disconn_req(chan, ECONNRESET);
6663	}
6664
6665	return 0;
6666
6667drop:
6668	kfree_skb(skb);
6669	return 0;
6670}
6671
6672static void l2cap_chan_le_send_credits(struct l2cap_chan *chan)
6673{
6674	struct l2cap_conn *conn = chan->conn;
6675	struct l2cap_le_credits pkt;
6676	u16 return_credits;
6677
6678	/* We return more credits to the sender only after the amount of
6679	 * credits falls below half of the initial amount.
6680	 */
6681	if (chan->rx_credits >= (le_max_credits + 1) / 2)
6682		return;
6683
6684	return_credits = le_max_credits - chan->rx_credits;
6685
6686	BT_DBG("chan %p returning %u credits to sender", chan, return_credits);
6687
6688	chan->rx_credits += return_credits;
6689
6690	pkt.cid     = cpu_to_le16(chan->scid);
6691	pkt.credits = cpu_to_le16(return_credits);
6692
6693	chan->ident = l2cap_get_ident(conn);
6694
6695	l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CREDITS, sizeof(pkt), &pkt);
6696}
6697
6698static int l2cap_le_data_rcv(struct l2cap_chan *chan, struct sk_buff *skb)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
6699{
6700	int err;
6701
6702	if (!chan->rx_credits) {
6703		BT_ERR("No credits to receive LE L2CAP data");
6704		l2cap_send_disconn_req(chan, ECONNRESET);
6705		return -ENOBUFS;
6706	}
6707
6708	if (chan->imtu < skb->len) {
6709		BT_ERR("Too big LE L2CAP PDU");
6710		return -ENOBUFS;
6711	}
6712
6713	chan->rx_credits--;
6714	BT_DBG("rx_credits %u -> %u", chan->rx_credits + 1, chan->rx_credits);
6715
6716	l2cap_chan_le_send_credits(chan);
 
 
 
 
6717
6718	err = 0;
6719
6720	if (!chan->sdu) {
6721		u16 sdu_len;
6722
6723		sdu_len = get_unaligned_le16(skb->data);
6724		skb_pull(skb, L2CAP_SDULEN_SIZE);
6725
6726		BT_DBG("Start of new SDU. sdu_len %u skb->len %u imtu %u",
6727		       sdu_len, skb->len, chan->imtu);
6728
6729		if (sdu_len > chan->imtu) {
6730			BT_ERR("Too big LE L2CAP SDU length received");
6731			err = -EMSGSIZE;
6732			goto failed;
6733		}
6734
6735		if (skb->len > sdu_len) {
6736			BT_ERR("Too much LE L2CAP data received");
6737			err = -EINVAL;
6738			goto failed;
6739		}
6740
6741		if (skb->len == sdu_len)
6742			return chan->ops->recv(chan, skb);
6743
6744		chan->sdu = skb;
6745		chan->sdu_len = sdu_len;
6746		chan->sdu_last_frag = skb;
6747
 
 
 
 
 
 
 
 
 
 
6748		return 0;
6749	}
6750
6751	BT_DBG("SDU fragment. chan->sdu->len %u skb->len %u chan->sdu_len %u",
6752	       chan->sdu->len, skb->len, chan->sdu_len);
6753
6754	if (chan->sdu->len + skb->len > chan->sdu_len) {
6755		BT_ERR("Too much LE L2CAP data received");
6756		err = -EINVAL;
6757		goto failed;
6758	}
6759
6760	append_skb_frag(chan->sdu, skb, &chan->sdu_last_frag);
6761	skb = NULL;
6762
6763	if (chan->sdu->len == chan->sdu_len) {
6764		err = chan->ops->recv(chan, chan->sdu);
6765		if (!err) {
6766			chan->sdu = NULL;
6767			chan->sdu_last_frag = NULL;
6768			chan->sdu_len = 0;
6769		}
6770	}
6771
6772failed:
6773	if (err) {
6774		kfree_skb(skb);
6775		kfree_skb(chan->sdu);
6776		chan->sdu = NULL;
6777		chan->sdu_last_frag = NULL;
6778		chan->sdu_len = 0;
6779	}
6780
6781	/* We can't return an error here since we took care of the skb
6782	 * freeing internally. An error return would cause the caller to
6783	 * do a double-free of the skb.
6784	 */
6785	return 0;
6786}
6787
6788static void l2cap_data_channel(struct l2cap_conn *conn, u16 cid,
6789			       struct sk_buff *skb)
6790{
6791	struct l2cap_chan *chan;
6792
6793	chan = l2cap_get_chan_by_scid(conn, cid);
6794	if (!chan) {
6795		if (cid == L2CAP_CID_A2MP) {
6796			chan = a2mp_channel_create(conn, skb);
6797			if (!chan) {
6798				kfree_skb(skb);
6799				return;
6800			}
6801
6802			l2cap_chan_lock(chan);
6803		} else {
6804			BT_DBG("unknown cid 0x%4.4x", cid);
6805			/* Drop packet and return */
6806			kfree_skb(skb);
6807			return;
6808		}
6809	}
6810
6811	BT_DBG("chan %p, len %d", chan, skb->len);
6812
6813	/* If we receive data on a fixed channel before the info req/rsp
6814	 * procdure is done simply assume that the channel is supported
6815	 * and mark it as ready.
6816	 */
6817	if (chan->chan_type == L2CAP_CHAN_FIXED)
6818		l2cap_chan_ready(chan);
6819
6820	if (chan->state != BT_CONNECTED)
6821		goto drop;
6822
6823	switch (chan->mode) {
6824	case L2CAP_MODE_LE_FLOWCTL:
6825		if (l2cap_le_data_rcv(chan, skb) < 0)
 
6826			goto drop;
6827
6828		goto done;
6829
6830	case L2CAP_MODE_BASIC:
6831		/* If socket recv buffers overflows we drop data here
6832		 * which is *bad* because L2CAP has to be reliable.
6833		 * But we don't have any other choice. L2CAP doesn't
6834		 * provide flow control mechanism. */
6835
6836		if (chan->imtu < skb->len) {
6837			BT_ERR("Dropping L2CAP data: receive buffer overflow");
6838			goto drop;
6839		}
6840
6841		if (!chan->ops->recv(chan, skb))
6842			goto done;
6843		break;
6844
6845	case L2CAP_MODE_ERTM:
6846	case L2CAP_MODE_STREAMING:
6847		l2cap_data_rcv(chan, skb);
6848		goto done;
6849
6850	default:
6851		BT_DBG("chan %p: bad mode 0x%2.2x", chan, chan->mode);
6852		break;
6853	}
6854
6855drop:
6856	kfree_skb(skb);
6857
6858done:
6859	l2cap_chan_unlock(chan);
6860}
6861
6862static void l2cap_conless_channel(struct l2cap_conn *conn, __le16 psm,
6863				  struct sk_buff *skb)
6864{
6865	struct hci_conn *hcon = conn->hcon;
6866	struct l2cap_chan *chan;
6867
6868	if (hcon->type != ACL_LINK)
6869		goto free_skb;
6870
6871	chan = l2cap_global_chan_by_psm(0, psm, &hcon->src, &hcon->dst,
6872					ACL_LINK);
6873	if (!chan)
6874		goto free_skb;
6875
6876	BT_DBG("chan %p, len %d", chan, skb->len);
6877
6878	if (chan->state != BT_BOUND && chan->state != BT_CONNECTED)
6879		goto drop;
6880
6881	if (chan->imtu < skb->len)
6882		goto drop;
6883
6884	/* Store remote BD_ADDR and PSM for msg_name */
6885	bacpy(&bt_cb(skb)->l2cap.bdaddr, &hcon->dst);
6886	bt_cb(skb)->l2cap.psm = psm;
6887
6888	if (!chan->ops->recv(chan, skb)) {
6889		l2cap_chan_put(chan);
6890		return;
6891	}
6892
6893drop:
6894	l2cap_chan_put(chan);
6895free_skb:
6896	kfree_skb(skb);
6897}
6898
6899static void l2cap_recv_frame(struct l2cap_conn *conn, struct sk_buff *skb)
6900{
6901	struct l2cap_hdr *lh = (void *) skb->data;
6902	struct hci_conn *hcon = conn->hcon;
6903	u16 cid, len;
6904	__le16 psm;
6905
6906	if (hcon->state != BT_CONNECTED) {
6907		BT_DBG("queueing pending rx skb");
6908		skb_queue_tail(&conn->pending_rx, skb);
6909		return;
6910	}
6911
6912	skb_pull(skb, L2CAP_HDR_SIZE);
6913	cid = __le16_to_cpu(lh->cid);
6914	len = __le16_to_cpu(lh->len);
6915
6916	if (len != skb->len) {
6917		kfree_skb(skb);
6918		return;
6919	}
6920
6921	/* Since we can't actively block incoming LE connections we must
6922	 * at least ensure that we ignore incoming data from them.
6923	 */
6924	if (hcon->type == LE_LINK &&
6925	    hci_bdaddr_list_lookup(&hcon->hdev->blacklist, &hcon->dst,
6926				   bdaddr_dst_type(hcon))) {
6927		kfree_skb(skb);
6928		return;
6929	}
6930
6931	BT_DBG("len %d, cid 0x%4.4x", len, cid);
6932
6933	switch (cid) {
6934	case L2CAP_CID_SIGNALING:
6935		l2cap_sig_channel(conn, skb);
6936		break;
6937
6938	case L2CAP_CID_CONN_LESS:
6939		psm = get_unaligned((__le16 *) skb->data);
6940		skb_pull(skb, L2CAP_PSMLEN_SIZE);
6941		l2cap_conless_channel(conn, psm, skb);
6942		break;
6943
6944	case L2CAP_CID_LE_SIGNALING:
6945		l2cap_le_sig_channel(conn, skb);
6946		break;
6947
6948	default:
6949		l2cap_data_channel(conn, cid, skb);
6950		break;
6951	}
6952}
6953
6954static void process_pending_rx(struct work_struct *work)
6955{
6956	struct l2cap_conn *conn = container_of(work, struct l2cap_conn,
6957					       pending_rx_work);
6958	struct sk_buff *skb;
6959
6960	BT_DBG("");
6961
6962	while ((skb = skb_dequeue(&conn->pending_rx)))
6963		l2cap_recv_frame(conn, skb);
6964}
6965
6966static struct l2cap_conn *l2cap_conn_add(struct hci_conn *hcon)
6967{
6968	struct l2cap_conn *conn = hcon->l2cap_data;
6969	struct hci_chan *hchan;
6970
6971	if (conn)
6972		return conn;
6973
6974	hchan = hci_chan_create(hcon);
6975	if (!hchan)
6976		return NULL;
6977
6978	conn = kzalloc(sizeof(*conn), GFP_KERNEL);
6979	if (!conn) {
6980		hci_chan_del(hchan);
6981		return NULL;
6982	}
6983
6984	kref_init(&conn->ref);
6985	hcon->l2cap_data = conn;
6986	conn->hcon = hci_conn_get(hcon);
6987	conn->hchan = hchan;
6988
6989	BT_DBG("hcon %p conn %p hchan %p", hcon, conn, hchan);
6990
6991	switch (hcon->type) {
6992	case LE_LINK:
6993		if (hcon->hdev->le_mtu) {
6994			conn->mtu = hcon->hdev->le_mtu;
6995			break;
6996		}
6997		/* fall through */
6998	default:
6999		conn->mtu = hcon->hdev->acl_mtu;
7000		break;
7001	}
7002
7003	conn->feat_mask = 0;
7004
7005	conn->local_fixed_chan = L2CAP_FC_SIG_BREDR | L2CAP_FC_CONNLESS;
7006
7007	if (hcon->type == ACL_LINK &&
7008	    hci_dev_test_flag(hcon->hdev, HCI_HS_ENABLED))
7009		conn->local_fixed_chan |= L2CAP_FC_A2MP;
7010
7011	if (hci_dev_test_flag(hcon->hdev, HCI_LE_ENABLED) &&
7012	    (bredr_sc_enabled(hcon->hdev) ||
7013	     hci_dev_test_flag(hcon->hdev, HCI_FORCE_BREDR_SMP)))
7014		conn->local_fixed_chan |= L2CAP_FC_SMP_BREDR;
7015
7016	mutex_init(&conn->ident_lock);
7017	mutex_init(&conn->chan_lock);
7018
7019	INIT_LIST_HEAD(&conn->chan_l);
7020	INIT_LIST_HEAD(&conn->users);
7021
7022	INIT_DELAYED_WORK(&conn->info_timer, l2cap_info_timeout);
7023
7024	skb_queue_head_init(&conn->pending_rx);
7025	INIT_WORK(&conn->pending_rx_work, process_pending_rx);
7026	INIT_WORK(&conn->id_addr_update_work, l2cap_conn_update_id_addr);
7027
7028	conn->disc_reason = HCI_ERROR_REMOTE_USER_TERM;
7029
7030	return conn;
7031}
7032
7033static bool is_valid_psm(u16 psm, u8 dst_type) {
 
7034	if (!psm)
7035		return false;
7036
7037	if (bdaddr_type_is_le(dst_type))
7038		return (psm <= 0x00ff);
7039
7040	/* PSM must be odd and lsb of upper byte must be 0 */
7041	return ((psm & 0x0101) == 0x0001);
7042}
7043
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
7044int l2cap_chan_connect(struct l2cap_chan *chan, __le16 psm, u16 cid,
7045		       bdaddr_t *dst, u8 dst_type)
7046{
7047	struct l2cap_conn *conn;
7048	struct hci_conn *hcon;
7049	struct hci_dev *hdev;
7050	int err;
7051
7052	BT_DBG("%pMR -> %pMR (type %u) psm 0x%2.2x", &chan->src, dst,
7053	       dst_type, __le16_to_cpu(psm));
7054
7055	hdev = hci_get_route(dst, &chan->src);
7056	if (!hdev)
7057		return -EHOSTUNREACH;
7058
7059	hci_dev_lock(hdev);
7060
7061	if (!is_valid_psm(__le16_to_cpu(psm), dst_type) && !cid &&
7062	    chan->chan_type != L2CAP_CHAN_RAW) {
7063		err = -EINVAL;
7064		goto done;
7065	}
7066
7067	if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED && !psm) {
7068		err = -EINVAL;
7069		goto done;
7070	}
7071
7072	if (chan->chan_type == L2CAP_CHAN_FIXED && !cid) {
7073		err = -EINVAL;
7074		goto done;
7075	}
7076
7077	switch (chan->mode) {
7078	case L2CAP_MODE_BASIC:
7079		break;
7080	case L2CAP_MODE_LE_FLOWCTL:
7081		l2cap_le_flowctl_init(chan);
 
 
 
 
 
7082		break;
7083	case L2CAP_MODE_ERTM:
7084	case L2CAP_MODE_STREAMING:
7085		if (!disable_ertm)
7086			break;
7087		/* fall through */
7088	default:
7089		err = -EOPNOTSUPP;
7090		goto done;
7091	}
7092
7093	switch (chan->state) {
7094	case BT_CONNECT:
7095	case BT_CONNECT2:
7096	case BT_CONFIG:
7097		/* Already connecting */
7098		err = 0;
7099		goto done;
7100
7101	case BT_CONNECTED:
7102		/* Already connected */
7103		err = -EISCONN;
7104		goto done;
7105
7106	case BT_OPEN:
7107	case BT_BOUND:
7108		/* Can connect */
7109		break;
7110
7111	default:
7112		err = -EBADFD;
7113		goto done;
7114	}
7115
7116	/* Set destination address and psm */
7117	bacpy(&chan->dst, dst);
7118	chan->dst_type = dst_type;
7119
7120	chan->psm = psm;
7121	chan->dcid = cid;
7122
7123	if (bdaddr_type_is_le(dst_type)) {
7124		/* Convert from L2CAP channel address type to HCI address type
7125		 */
7126		if (dst_type == BDADDR_LE_PUBLIC)
7127			dst_type = ADDR_LE_DEV_PUBLIC;
7128		else
7129			dst_type = ADDR_LE_DEV_RANDOM;
7130
7131		if (hci_dev_test_flag(hdev, HCI_ADVERTISING))
7132			hcon = hci_connect_le(hdev, dst, dst_type,
7133					      chan->sec_level,
7134					      HCI_LE_CONN_TIMEOUT,
7135					      HCI_ROLE_SLAVE);
7136		else
7137			hcon = hci_connect_le_scan(hdev, dst, dst_type,
7138						   chan->sec_level,
7139						   HCI_LE_CONN_TIMEOUT);
 
7140
7141	} else {
7142		u8 auth_type = l2cap_get_auth_type(chan);
7143		hcon = hci_connect_acl(hdev, dst, chan->sec_level, auth_type);
 
7144	}
7145
7146	if (IS_ERR(hcon)) {
7147		err = PTR_ERR(hcon);
7148		goto done;
7149	}
7150
7151	conn = l2cap_conn_add(hcon);
7152	if (!conn) {
7153		hci_conn_drop(hcon);
7154		err = -ENOMEM;
7155		goto done;
7156	}
7157
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
7158	mutex_lock(&conn->chan_lock);
7159	l2cap_chan_lock(chan);
7160
7161	if (cid && __l2cap_get_chan_by_dcid(conn, cid)) {
7162		hci_conn_drop(hcon);
7163		err = -EBUSY;
7164		goto chan_unlock;
7165	}
7166
7167	/* Update source addr of the socket */
7168	bacpy(&chan->src, &hcon->src);
7169	chan->src_type = bdaddr_src_type(hcon);
7170
7171	__l2cap_chan_add(conn, chan);
7172
7173	/* l2cap_chan_add takes its own ref so we can drop this one */
7174	hci_conn_drop(hcon);
7175
7176	l2cap_state_change(chan, BT_CONNECT);
7177	__set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
7178
7179	/* Release chan->sport so that it can be reused by other
7180	 * sockets (as it's only used for listening sockets).
7181	 */
7182	write_lock(&chan_list_lock);
7183	chan->sport = 0;
7184	write_unlock(&chan_list_lock);
7185
7186	if (hcon->state == BT_CONNECTED) {
7187		if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
7188			__clear_chan_timer(chan);
7189			if (l2cap_chan_check_security(chan, true))
7190				l2cap_state_change(chan, BT_CONNECTED);
7191		} else
7192			l2cap_do_start(chan);
7193	}
7194
7195	err = 0;
7196
7197chan_unlock:
7198	l2cap_chan_unlock(chan);
7199	mutex_unlock(&conn->chan_lock);
7200done:
7201	hci_dev_unlock(hdev);
7202	hci_dev_put(hdev);
7203	return err;
7204}
7205EXPORT_SYMBOL_GPL(l2cap_chan_connect);
7206
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
7207/* ---- L2CAP interface with lower layer (HCI) ---- */
7208
7209int l2cap_connect_ind(struct hci_dev *hdev, bdaddr_t *bdaddr)
7210{
7211	int exact = 0, lm1 = 0, lm2 = 0;
7212	struct l2cap_chan *c;
7213
7214	BT_DBG("hdev %s, bdaddr %pMR", hdev->name, bdaddr);
7215
7216	/* Find listening sockets and check their link_mode */
7217	read_lock(&chan_list_lock);
7218	list_for_each_entry(c, &chan_list, global_l) {
7219		if (c->state != BT_LISTEN)
7220			continue;
7221
7222		if (!bacmp(&c->src, &hdev->bdaddr)) {
7223			lm1 |= HCI_LM_ACCEPT;
7224			if (test_bit(FLAG_ROLE_SWITCH, &c->flags))
7225				lm1 |= HCI_LM_MASTER;
7226			exact++;
7227		} else if (!bacmp(&c->src, BDADDR_ANY)) {
7228			lm2 |= HCI_LM_ACCEPT;
7229			if (test_bit(FLAG_ROLE_SWITCH, &c->flags))
7230				lm2 |= HCI_LM_MASTER;
7231		}
7232	}
7233	read_unlock(&chan_list_lock);
7234
7235	return exact ? lm1 : lm2;
7236}
7237
7238/* Find the next fixed channel in BT_LISTEN state, continue iteration
7239 * from an existing channel in the list or from the beginning of the
7240 * global list (by passing NULL as first parameter).
7241 */
7242static struct l2cap_chan *l2cap_global_fixed_chan(struct l2cap_chan *c,
7243						  struct hci_conn *hcon)
7244{
7245	u8 src_type = bdaddr_src_type(hcon);
7246
7247	read_lock(&chan_list_lock);
7248
7249	if (c)
7250		c = list_next_entry(c, global_l);
7251	else
7252		c = list_entry(chan_list.next, typeof(*c), global_l);
7253
7254	list_for_each_entry_from(c, &chan_list, global_l) {
7255		if (c->chan_type != L2CAP_CHAN_FIXED)
7256			continue;
7257		if (c->state != BT_LISTEN)
7258			continue;
7259		if (bacmp(&c->src, &hcon->src) && bacmp(&c->src, BDADDR_ANY))
7260			continue;
7261		if (src_type != c->src_type)
7262			continue;
7263
7264		l2cap_chan_hold(c);
7265		read_unlock(&chan_list_lock);
7266		return c;
7267	}
7268
7269	read_unlock(&chan_list_lock);
7270
7271	return NULL;
7272}
7273
7274static void l2cap_connect_cfm(struct hci_conn *hcon, u8 status)
7275{
7276	struct hci_dev *hdev = hcon->hdev;
7277	struct l2cap_conn *conn;
7278	struct l2cap_chan *pchan;
7279	u8 dst_type;
7280
7281	if (hcon->type != ACL_LINK && hcon->type != LE_LINK)
7282		return;
7283
7284	BT_DBG("hcon %p bdaddr %pMR status %d", hcon, &hcon->dst, status);
7285
7286	if (status) {
7287		l2cap_conn_del(hcon, bt_to_errno(status));
7288		return;
7289	}
7290
7291	conn = l2cap_conn_add(hcon);
7292	if (!conn)
7293		return;
7294
7295	dst_type = bdaddr_dst_type(hcon);
7296
7297	/* If device is blocked, do not create channels for it */
7298	if (hci_bdaddr_list_lookup(&hdev->blacklist, &hcon->dst, dst_type))
7299		return;
7300
7301	/* Find fixed channels and notify them of the new connection. We
7302	 * use multiple individual lookups, continuing each time where
7303	 * we left off, because the list lock would prevent calling the
7304	 * potentially sleeping l2cap_chan_lock() function.
7305	 */
7306	pchan = l2cap_global_fixed_chan(NULL, hcon);
7307	while (pchan) {
7308		struct l2cap_chan *chan, *next;
7309
7310		/* Client fixed channels should override server ones */
7311		if (__l2cap_get_chan_by_dcid(conn, pchan->scid))
7312			goto next;
7313
7314		l2cap_chan_lock(pchan);
7315		chan = pchan->ops->new_connection(pchan);
7316		if (chan) {
7317			bacpy(&chan->src, &hcon->src);
7318			bacpy(&chan->dst, &hcon->dst);
7319			chan->src_type = bdaddr_src_type(hcon);
7320			chan->dst_type = dst_type;
7321
7322			__l2cap_chan_add(conn, chan);
7323		}
7324
7325		l2cap_chan_unlock(pchan);
7326next:
7327		next = l2cap_global_fixed_chan(pchan, hcon);
7328		l2cap_chan_put(pchan);
7329		pchan = next;
7330	}
7331
7332	l2cap_conn_ready(conn);
7333}
7334
7335int l2cap_disconn_ind(struct hci_conn *hcon)
7336{
7337	struct l2cap_conn *conn = hcon->l2cap_data;
7338
7339	BT_DBG("hcon %p", hcon);
7340
7341	if (!conn)
7342		return HCI_ERROR_REMOTE_USER_TERM;
7343	return conn->disc_reason;
7344}
7345
7346static void l2cap_disconn_cfm(struct hci_conn *hcon, u8 reason)
7347{
7348	if (hcon->type != ACL_LINK && hcon->type != LE_LINK)
7349		return;
7350
7351	BT_DBG("hcon %p reason %d", hcon, reason);
7352
7353	l2cap_conn_del(hcon, bt_to_errno(reason));
7354}
7355
7356static inline void l2cap_check_encryption(struct l2cap_chan *chan, u8 encrypt)
7357{
7358	if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED)
7359		return;
7360
7361	if (encrypt == 0x00) {
7362		if (chan->sec_level == BT_SECURITY_MEDIUM) {
7363			__set_chan_timer(chan, L2CAP_ENC_TIMEOUT);
7364		} else if (chan->sec_level == BT_SECURITY_HIGH ||
7365			   chan->sec_level == BT_SECURITY_FIPS)
7366			l2cap_chan_close(chan, ECONNREFUSED);
7367	} else {
7368		if (chan->sec_level == BT_SECURITY_MEDIUM)
7369			__clear_chan_timer(chan);
7370	}
7371}
7372
7373static void l2cap_security_cfm(struct hci_conn *hcon, u8 status, u8 encrypt)
7374{
7375	struct l2cap_conn *conn = hcon->l2cap_data;
7376	struct l2cap_chan *chan;
7377
7378	if (!conn)
7379		return;
7380
7381	BT_DBG("conn %p status 0x%2.2x encrypt %u", conn, status, encrypt);
7382
7383	mutex_lock(&conn->chan_lock);
7384
7385	list_for_each_entry(chan, &conn->chan_l, list) {
7386		l2cap_chan_lock(chan);
7387
7388		BT_DBG("chan %p scid 0x%4.4x state %s", chan, chan->scid,
7389		       state_to_string(chan->state));
7390
7391		if (chan->scid == L2CAP_CID_A2MP) {
7392			l2cap_chan_unlock(chan);
7393			continue;
7394		}
7395
7396		if (!status && encrypt)
7397			chan->sec_level = hcon->sec_level;
7398
7399		if (!__l2cap_no_conn_pending(chan)) {
7400			l2cap_chan_unlock(chan);
7401			continue;
7402		}
7403
7404		if (!status && (chan->state == BT_CONNECTED ||
7405				chan->state == BT_CONFIG)) {
7406			chan->ops->resume(chan);
7407			l2cap_check_encryption(chan, encrypt);
7408			l2cap_chan_unlock(chan);
7409			continue;
7410		}
7411
7412		if (chan->state == BT_CONNECT) {
7413			if (!status)
7414				l2cap_start_connection(chan);
7415			else
7416				__set_chan_timer(chan, L2CAP_DISC_TIMEOUT);
7417		} else if (chan->state == BT_CONNECT2 &&
7418			   chan->mode != L2CAP_MODE_LE_FLOWCTL) {
 
7419			struct l2cap_conn_rsp rsp;
7420			__u16 res, stat;
7421
7422			if (!status) {
7423				if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
7424					res = L2CAP_CR_PEND;
7425					stat = L2CAP_CS_AUTHOR_PEND;
7426					chan->ops->defer(chan);
7427				} else {
7428					l2cap_state_change(chan, BT_CONFIG);
7429					res = L2CAP_CR_SUCCESS;
7430					stat = L2CAP_CS_NO_INFO;
7431				}
7432			} else {
7433				l2cap_state_change(chan, BT_DISCONN);
7434				__set_chan_timer(chan, L2CAP_DISC_TIMEOUT);
7435				res = L2CAP_CR_SEC_BLOCK;
7436				stat = L2CAP_CS_NO_INFO;
7437			}
7438
7439			rsp.scid   = cpu_to_le16(chan->dcid);
7440			rsp.dcid   = cpu_to_le16(chan->scid);
7441			rsp.result = cpu_to_le16(res);
7442			rsp.status = cpu_to_le16(stat);
7443			l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP,
7444				       sizeof(rsp), &rsp);
7445
7446			if (!test_bit(CONF_REQ_SENT, &chan->conf_state) &&
7447			    res == L2CAP_CR_SUCCESS) {
7448				char buf[128];
7449				set_bit(CONF_REQ_SENT, &chan->conf_state);
7450				l2cap_send_cmd(conn, l2cap_get_ident(conn),
7451					       L2CAP_CONF_REQ,
7452					       l2cap_build_conf_req(chan, buf),
7453					       buf);
7454				chan->num_conf_req++;
7455			}
7456		}
7457
7458		l2cap_chan_unlock(chan);
7459	}
7460
7461	mutex_unlock(&conn->chan_lock);
7462}
7463
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
7464void l2cap_recv_acldata(struct hci_conn *hcon, struct sk_buff *skb, u16 flags)
7465{
7466	struct l2cap_conn *conn = hcon->l2cap_data;
7467	struct l2cap_hdr *hdr;
7468	int len;
7469
7470	/* For AMP controller do not create l2cap conn */
7471	if (!conn && hcon->hdev->dev_type != HCI_BREDR)
7472		goto drop;
7473
7474	if (!conn)
7475		conn = l2cap_conn_add(hcon);
7476
7477	if (!conn)
7478		goto drop;
7479
7480	BT_DBG("conn %p len %d flags 0x%x", conn, skb->len, flags);
7481
7482	switch (flags) {
7483	case ACL_START:
7484	case ACL_START_NO_FLUSH:
7485	case ACL_COMPLETE:
7486		if (conn->rx_len) {
7487			BT_ERR("Unexpected start frame (len %d)", skb->len);
7488			kfree_skb(conn->rx_skb);
7489			conn->rx_skb = NULL;
7490			conn->rx_len = 0;
7491			l2cap_conn_unreliable(conn, ECOMM);
7492		}
7493
7494		/* Start fragment always begin with Basic L2CAP header */
7495		if (skb->len < L2CAP_HDR_SIZE) {
7496			BT_ERR("Frame is too short (len %d)", skb->len);
7497			l2cap_conn_unreliable(conn, ECOMM);
7498			goto drop;
 
 
 
7499		}
7500
7501		hdr = (struct l2cap_hdr *) skb->data;
7502		len = __le16_to_cpu(hdr->len) + L2CAP_HDR_SIZE;
7503
7504		if (len == skb->len) {
7505			/* Complete frame received */
7506			l2cap_recv_frame(conn, skb);
7507			return;
7508		}
7509
7510		BT_DBG("Start: total len %d, frag len %d", len, skb->len);
7511
7512		if (skb->len > len) {
7513			BT_ERR("Frame is too long (len %d, expected len %d)",
7514			       skb->len, len);
7515			l2cap_conn_unreliable(conn, ECOMM);
7516			goto drop;
7517		}
7518
7519		/* Allocate skb for the complete frame (with header) */
7520		conn->rx_skb = bt_skb_alloc(len, GFP_KERNEL);
7521		if (!conn->rx_skb)
7522			goto drop;
7523
7524		skb_copy_from_linear_data(skb, skb_put(conn->rx_skb, skb->len),
7525					  skb->len);
7526		conn->rx_len = len - skb->len;
7527		break;
7528
7529	case ACL_CONT:
7530		BT_DBG("Cont: frag len %d (expecting %d)", skb->len, conn->rx_len);
7531
7532		if (!conn->rx_len) {
7533			BT_ERR("Unexpected continuation frame (len %d)", skb->len);
7534			l2cap_conn_unreliable(conn, ECOMM);
7535			goto drop;
7536		}
7537
 
 
 
 
 
 
 
 
 
 
 
 
7538		if (skb->len > conn->rx_len) {
7539			BT_ERR("Fragment is too long (len %d, expected %d)",
7540			       skb->len, conn->rx_len);
7541			kfree_skb(conn->rx_skb);
7542			conn->rx_skb = NULL;
7543			conn->rx_len = 0;
7544			l2cap_conn_unreliable(conn, ECOMM);
7545			goto drop;
7546		}
7547
7548		skb_copy_from_linear_data(skb, skb_put(conn->rx_skb, skb->len),
7549					  skb->len);
7550		conn->rx_len -= skb->len;
7551
7552		if (!conn->rx_len) {
7553			/* Complete frame received. l2cap_recv_frame
7554			 * takes ownership of the skb so set the global
7555			 * rx_skb pointer to NULL first.
7556			 */
7557			struct sk_buff *rx_skb = conn->rx_skb;
7558			conn->rx_skb = NULL;
7559			l2cap_recv_frame(conn, rx_skb);
7560		}
7561		break;
7562	}
7563
7564drop:
7565	kfree_skb(skb);
7566}
7567
7568static struct hci_cb l2cap_cb = {
7569	.name		= "L2CAP",
7570	.connect_cfm	= l2cap_connect_cfm,
7571	.disconn_cfm	= l2cap_disconn_cfm,
7572	.security_cfm	= l2cap_security_cfm,
7573};
7574
7575static int l2cap_debugfs_show(struct seq_file *f, void *p)
7576{
7577	struct l2cap_chan *c;
7578
7579	read_lock(&chan_list_lock);
7580
7581	list_for_each_entry(c, &chan_list, global_l) {
7582		seq_printf(f, "%pMR (%u) %pMR (%u) %d %d 0x%4.4x 0x%4.4x %d %d %d %d\n",
7583			   &c->src, c->src_type, &c->dst, c->dst_type,
7584			   c->state, __le16_to_cpu(c->psm),
7585			   c->scid, c->dcid, c->imtu, c->omtu,
7586			   c->sec_level, c->mode);
7587	}
7588
7589	read_unlock(&chan_list_lock);
7590
7591	return 0;
7592}
7593
7594static int l2cap_debugfs_open(struct inode *inode, struct file *file)
7595{
7596	return single_open(file, l2cap_debugfs_show, inode->i_private);
7597}
7598
7599static const struct file_operations l2cap_debugfs_fops = {
7600	.open		= l2cap_debugfs_open,
7601	.read		= seq_read,
7602	.llseek		= seq_lseek,
7603	.release	= single_release,
7604};
7605
7606static struct dentry *l2cap_debugfs;
7607
7608int __init l2cap_init(void)
7609{
7610	int err;
7611
7612	err = l2cap_init_sockets();
7613	if (err < 0)
7614		return err;
7615
7616	hci_register_cb(&l2cap_cb);
7617
7618	if (IS_ERR_OR_NULL(bt_debugfs))
7619		return 0;
7620
7621	l2cap_debugfs = debugfs_create_file("l2cap", 0444, bt_debugfs,
7622					    NULL, &l2cap_debugfs_fops);
7623
7624	debugfs_create_u16("l2cap_le_max_credits", 0644, bt_debugfs,
7625			   &le_max_credits);
7626	debugfs_create_u16("l2cap_le_default_mps", 0644, bt_debugfs,
7627			   &le_default_mps);
7628
7629	return 0;
7630}
7631
7632void l2cap_exit(void)
7633{
7634	debugfs_remove(l2cap_debugfs);
7635	hci_unregister_cb(&l2cap_cb);
7636	l2cap_cleanup_sockets();
7637}
7638
7639module_param(disable_ertm, bool, 0644);
7640MODULE_PARM_DESC(disable_ertm, "Disable enhanced retransmission mode");
v5.14.15
   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;
  48bool enable_ecred;
  49
  50static u32 l2cap_feat_mask = L2CAP_FEAT_FIXED_CHAN | L2CAP_FEAT_UCD;
  51
  52static LIST_HEAD(chan_list);
  53static DEFINE_RWLOCK(chan_list_lock);
  54
 
 
 
  55static struct sk_buff *l2cap_build_cmd(struct l2cap_conn *conn,
  56				       u8 code, u8 ident, u16 dlen, void *data);
  57static void l2cap_send_cmd(struct l2cap_conn *conn, u8 ident, u8 code, u16 len,
  58			   void *data);
  59static int l2cap_build_conf_req(struct l2cap_chan *chan, void *data, size_t data_size);
  60static void l2cap_send_disconn_req(struct l2cap_chan *chan, int err);
  61
  62static void l2cap_tx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
  63		     struct sk_buff_head *skbs, u8 event);
  64
  65static inline u8 bdaddr_type(u8 link_type, u8 bdaddr_type)
  66{
  67	if (link_type == LE_LINK) {
  68		if (bdaddr_type == ADDR_LE_DEV_PUBLIC)
  69			return BDADDR_LE_PUBLIC;
  70		else
  71			return BDADDR_LE_RANDOM;
  72	}
  73
  74	return BDADDR_BREDR;
  75}
  76
  77static inline u8 bdaddr_src_type(struct hci_conn *hcon)
  78{
  79	return bdaddr_type(hcon->type, hcon->src_type);
  80}
  81
  82static inline u8 bdaddr_dst_type(struct hci_conn *hcon)
  83{
  84	return bdaddr_type(hcon->type, hcon->dst_type);
  85}
  86
  87/* ---- L2CAP channels ---- */
  88
  89static struct l2cap_chan *__l2cap_get_chan_by_dcid(struct l2cap_conn *conn,
  90						   u16 cid)
  91{
  92	struct l2cap_chan *c;
  93
  94	list_for_each_entry(c, &conn->chan_l, list) {
  95		if (c->dcid == cid)
  96			return c;
  97	}
  98	return NULL;
  99}
 100
 101static struct l2cap_chan *__l2cap_get_chan_by_scid(struct l2cap_conn *conn,
 102						   u16 cid)
 103{
 104	struct l2cap_chan *c;
 105
 106	list_for_each_entry(c, &conn->chan_l, list) {
 107		if (c->scid == cid)
 108			return c;
 109	}
 110	return NULL;
 111}
 112
 113/* Find channel with given SCID.
 114 * Returns locked channel. */
 115static struct l2cap_chan *l2cap_get_chan_by_scid(struct l2cap_conn *conn,
 116						 u16 cid)
 117{
 118	struct l2cap_chan *c;
 119
 120	mutex_lock(&conn->chan_lock);
 121	c = __l2cap_get_chan_by_scid(conn, cid);
 122	if (c)
 123		l2cap_chan_lock(c);
 124	mutex_unlock(&conn->chan_lock);
 125
 126	return c;
 127}
 128
 129/* Find channel with given DCID.
 130 * Returns locked channel.
 131 */
 132static struct l2cap_chan *l2cap_get_chan_by_dcid(struct l2cap_conn *conn,
 133						 u16 cid)
 134{
 135	struct l2cap_chan *c;
 136
 137	mutex_lock(&conn->chan_lock);
 138	c = __l2cap_get_chan_by_dcid(conn, cid);
 139	if (c)
 140		l2cap_chan_lock(c);
 141	mutex_unlock(&conn->chan_lock);
 142
 143	return c;
 144}
 145
 146static struct l2cap_chan *__l2cap_get_chan_by_ident(struct l2cap_conn *conn,
 147						    u8 ident)
 148{
 149	struct l2cap_chan *c;
 150
 151	list_for_each_entry(c, &conn->chan_l, list) {
 152		if (c->ident == ident)
 153			return c;
 154	}
 155	return NULL;
 156}
 157
 158static struct l2cap_chan *l2cap_get_chan_by_ident(struct l2cap_conn *conn,
 159						  u8 ident)
 160{
 161	struct l2cap_chan *c;
 162
 163	mutex_lock(&conn->chan_lock);
 164	c = __l2cap_get_chan_by_ident(conn, ident);
 165	if (c)
 166		l2cap_chan_lock(c);
 167	mutex_unlock(&conn->chan_lock);
 168
 169	return c;
 170}
 171
 172static struct l2cap_chan *__l2cap_global_chan_by_addr(__le16 psm, bdaddr_t *src,
 173						      u8 src_type)
 174{
 175	struct l2cap_chan *c;
 176
 177	list_for_each_entry(c, &chan_list, global_l) {
 178		if (src_type == BDADDR_BREDR && c->src_type != BDADDR_BREDR)
 179			continue;
 180
 181		if (src_type != BDADDR_BREDR && c->src_type == BDADDR_BREDR)
 182			continue;
 183
 184		if (c->sport == psm && !bacmp(&c->src, src))
 185			return c;
 186	}
 187	return NULL;
 188}
 189
 190int l2cap_add_psm(struct l2cap_chan *chan, bdaddr_t *src, __le16 psm)
 191{
 192	int err;
 193
 194	write_lock(&chan_list_lock);
 195
 196	if (psm && __l2cap_global_chan_by_addr(psm, src, chan->src_type)) {
 197		err = -EADDRINUSE;
 198		goto done;
 199	}
 200
 201	if (psm) {
 202		chan->psm = psm;
 203		chan->sport = psm;
 204		err = 0;
 205	} else {
 206		u16 p, start, end, incr;
 207
 208		if (chan->src_type == BDADDR_BREDR) {
 209			start = L2CAP_PSM_DYN_START;
 210			end = L2CAP_PSM_AUTO_END;
 211			incr = 2;
 212		} else {
 213			start = L2CAP_PSM_LE_DYN_START;
 214			end = L2CAP_PSM_LE_DYN_END;
 215			incr = 1;
 216		}
 217
 218		err = -EINVAL;
 219		for (p = start; p <= end; p += incr)
 220			if (!__l2cap_global_chan_by_addr(cpu_to_le16(p), src,
 221							 chan->src_type)) {
 222				chan->psm   = cpu_to_le16(p);
 223				chan->sport = cpu_to_le16(p);
 224				err = 0;
 225				break;
 226			}
 227	}
 228
 229done:
 230	write_unlock(&chan_list_lock);
 231	return err;
 232}
 233EXPORT_SYMBOL_GPL(l2cap_add_psm);
 234
 235int l2cap_add_scid(struct l2cap_chan *chan,  __u16 scid)
 236{
 237	write_lock(&chan_list_lock);
 238
 239	/* Override the defaults (which are for conn-oriented) */
 240	chan->omtu = L2CAP_DEFAULT_MTU;
 241	chan->chan_type = L2CAP_CHAN_FIXED;
 242
 243	chan->scid = scid;
 244
 245	write_unlock(&chan_list_lock);
 246
 247	return 0;
 248}
 249
 250static u16 l2cap_alloc_cid(struct l2cap_conn *conn)
 251{
 252	u16 cid, dyn_end;
 253
 254	if (conn->hcon->type == LE_LINK)
 255		dyn_end = L2CAP_CID_LE_DYN_END;
 256	else
 257		dyn_end = L2CAP_CID_DYN_END;
 258
 259	for (cid = L2CAP_CID_DYN_START; cid <= dyn_end; cid++) {
 260		if (!__l2cap_get_chan_by_scid(conn, cid))
 261			return cid;
 262	}
 263
 264	return 0;
 265}
 266
 267static void l2cap_state_change(struct l2cap_chan *chan, int state)
 268{
 269	BT_DBG("chan %p %s -> %s", chan, state_to_string(chan->state),
 270	       state_to_string(state));
 271
 272	chan->state = state;
 273	chan->ops->state_change(chan, state, 0);
 274}
 275
 276static inline void l2cap_state_change_and_error(struct l2cap_chan *chan,
 277						int state, int err)
 278{
 279	chan->state = state;
 280	chan->ops->state_change(chan, chan->state, err);
 281}
 282
 283static inline void l2cap_chan_set_err(struct l2cap_chan *chan, int err)
 284{
 285	chan->ops->state_change(chan, chan->state, err);
 286}
 287
 288static void __set_retrans_timer(struct l2cap_chan *chan)
 289{
 290	if (!delayed_work_pending(&chan->monitor_timer) &&
 291	    chan->retrans_timeout) {
 292		l2cap_set_timer(chan, &chan->retrans_timer,
 293				msecs_to_jiffies(chan->retrans_timeout));
 294	}
 295}
 296
 297static void __set_monitor_timer(struct l2cap_chan *chan)
 298{
 299	__clear_retrans_timer(chan);
 300	if (chan->monitor_timeout) {
 301		l2cap_set_timer(chan, &chan->monitor_timer,
 302				msecs_to_jiffies(chan->monitor_timeout));
 303	}
 304}
 305
 306static struct sk_buff *l2cap_ertm_seq_in_queue(struct sk_buff_head *head,
 307					       u16 seq)
 308{
 309	struct sk_buff *skb;
 310
 311	skb_queue_walk(head, skb) {
 312		if (bt_cb(skb)->l2cap.txseq == seq)
 313			return skb;
 314	}
 315
 316	return NULL;
 317}
 318
 319/* ---- L2CAP sequence number lists ---- */
 320
 321/* For ERTM, ordered lists of sequence numbers must be tracked for
 322 * SREJ requests that are received and for frames that are to be
 323 * retransmitted. These seq_list functions implement a singly-linked
 324 * list in an array, where membership in the list can also be checked
 325 * in constant time. Items can also be added to the tail of the list
 326 * and removed from the head in constant time, without further memory
 327 * allocs or frees.
 328 */
 329
 330static int l2cap_seq_list_init(struct l2cap_seq_list *seq_list, u16 size)
 331{
 332	size_t alloc_size, i;
 333
 334	/* Allocated size is a power of 2 to map sequence numbers
 335	 * (which may be up to 14 bits) in to a smaller array that is
 336	 * sized for the negotiated ERTM transmit windows.
 337	 */
 338	alloc_size = roundup_pow_of_two(size);
 339
 340	seq_list->list = kmalloc_array(alloc_size, sizeof(u16), GFP_KERNEL);
 341	if (!seq_list->list)
 342		return -ENOMEM;
 343
 344	seq_list->mask = alloc_size - 1;
 345	seq_list->head = L2CAP_SEQ_LIST_CLEAR;
 346	seq_list->tail = L2CAP_SEQ_LIST_CLEAR;
 347	for (i = 0; i < alloc_size; i++)
 348		seq_list->list[i] = L2CAP_SEQ_LIST_CLEAR;
 349
 350	return 0;
 351}
 352
 353static inline void l2cap_seq_list_free(struct l2cap_seq_list *seq_list)
 354{
 355	kfree(seq_list->list);
 356}
 357
 358static inline bool l2cap_seq_list_contains(struct l2cap_seq_list *seq_list,
 359					   u16 seq)
 360{
 361	/* Constant-time check for list membership */
 362	return seq_list->list[seq & seq_list->mask] != L2CAP_SEQ_LIST_CLEAR;
 363}
 364
 365static inline u16 l2cap_seq_list_pop(struct l2cap_seq_list *seq_list)
 366{
 367	u16 seq = seq_list->head;
 368	u16 mask = seq_list->mask;
 369
 370	seq_list->head = seq_list->list[seq & mask];
 371	seq_list->list[seq & mask] = L2CAP_SEQ_LIST_CLEAR;
 372
 373	if (seq_list->head == L2CAP_SEQ_LIST_TAIL) {
 374		seq_list->head = L2CAP_SEQ_LIST_CLEAR;
 375		seq_list->tail = L2CAP_SEQ_LIST_CLEAR;
 376	}
 377
 378	return seq;
 379}
 380
 381static void l2cap_seq_list_clear(struct l2cap_seq_list *seq_list)
 382{
 383	u16 i;
 384
 385	if (seq_list->head == L2CAP_SEQ_LIST_CLEAR)
 386		return;
 387
 388	for (i = 0; i <= seq_list->mask; i++)
 389		seq_list->list[i] = L2CAP_SEQ_LIST_CLEAR;
 390
 391	seq_list->head = L2CAP_SEQ_LIST_CLEAR;
 392	seq_list->tail = L2CAP_SEQ_LIST_CLEAR;
 393}
 394
 395static void l2cap_seq_list_append(struct l2cap_seq_list *seq_list, u16 seq)
 396{
 397	u16 mask = seq_list->mask;
 398
 399	/* All appends happen in constant time */
 400
 401	if (seq_list->list[seq & mask] != L2CAP_SEQ_LIST_CLEAR)
 402		return;
 403
 404	if (seq_list->tail == L2CAP_SEQ_LIST_CLEAR)
 405		seq_list->head = seq;
 406	else
 407		seq_list->list[seq_list->tail & mask] = seq;
 408
 409	seq_list->tail = seq;
 410	seq_list->list[seq & mask] = L2CAP_SEQ_LIST_TAIL;
 411}
 412
 413static void l2cap_chan_timeout(struct work_struct *work)
 414{
 415	struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
 416					       chan_timer.work);
 417	struct l2cap_conn *conn = chan->conn;
 418	int reason;
 419
 420	BT_DBG("chan %p state %s", chan, state_to_string(chan->state));
 421
 422	mutex_lock(&conn->chan_lock);
 423	/* __set_chan_timer() calls l2cap_chan_hold(chan) while scheduling
 424	 * this work. No need to call l2cap_chan_hold(chan) here again.
 425	 */
 426	l2cap_chan_lock(chan);
 427
 428	if (chan->state == BT_CONNECTED || chan->state == BT_CONFIG)
 429		reason = ECONNREFUSED;
 430	else if (chan->state == BT_CONNECT &&
 431		 chan->sec_level != BT_SECURITY_SDP)
 432		reason = ECONNREFUSED;
 433	else
 434		reason = ETIMEDOUT;
 435
 436	l2cap_chan_close(chan, reason);
 437
 
 
 438	chan->ops->close(chan);
 
 439
 440	l2cap_chan_unlock(chan);
 441	l2cap_chan_put(chan);
 442
 443	mutex_unlock(&conn->chan_lock);
 444}
 445
 446struct l2cap_chan *l2cap_chan_create(void)
 447{
 448	struct l2cap_chan *chan;
 449
 450	chan = kzalloc(sizeof(*chan), GFP_ATOMIC);
 451	if (!chan)
 452		return NULL;
 453
 454	skb_queue_head_init(&chan->tx_q);
 455	skb_queue_head_init(&chan->srej_q);
 456	mutex_init(&chan->lock);
 457
 458	/* Set default lock nesting level */
 459	atomic_set(&chan->nesting, L2CAP_NESTING_NORMAL);
 460
 461	write_lock(&chan_list_lock);
 462	list_add(&chan->global_l, &chan_list);
 463	write_unlock(&chan_list_lock);
 464
 465	INIT_DELAYED_WORK(&chan->chan_timer, l2cap_chan_timeout);
 466
 467	chan->state = BT_OPEN;
 468
 469	kref_init(&chan->kref);
 470
 471	/* This flag is cleared in l2cap_chan_ready() */
 472	set_bit(CONF_NOT_COMPLETE, &chan->conf_state);
 473
 474	BT_DBG("chan %p", chan);
 475
 476	return chan;
 477}
 478EXPORT_SYMBOL_GPL(l2cap_chan_create);
 479
 480static void l2cap_chan_destroy(struct kref *kref)
 481{
 482	struct l2cap_chan *chan = container_of(kref, struct l2cap_chan, kref);
 483
 484	BT_DBG("chan %p", chan);
 485
 486	write_lock(&chan_list_lock);
 487	list_del(&chan->global_l);
 488	write_unlock(&chan_list_lock);
 489
 490	kfree(chan);
 491}
 492
 493void l2cap_chan_hold(struct l2cap_chan *c)
 494{
 495	BT_DBG("chan %p orig refcnt %u", c, kref_read(&c->kref));
 496
 497	kref_get(&c->kref);
 498}
 499
 500void l2cap_chan_put(struct l2cap_chan *c)
 501{
 502	BT_DBG("chan %p orig refcnt %u", c, kref_read(&c->kref));
 503
 504	kref_put(&c->kref, l2cap_chan_destroy);
 505}
 506EXPORT_SYMBOL_GPL(l2cap_chan_put);
 507
 508void l2cap_chan_set_defaults(struct l2cap_chan *chan)
 509{
 510	chan->fcs  = L2CAP_FCS_CRC16;
 511	chan->max_tx = L2CAP_DEFAULT_MAX_TX;
 512	chan->tx_win = L2CAP_DEFAULT_TX_WINDOW;
 513	chan->tx_win_max = L2CAP_DEFAULT_TX_WINDOW;
 514	chan->remote_max_tx = chan->max_tx;
 515	chan->remote_tx_win = chan->tx_win;
 516	chan->ack_win = L2CAP_DEFAULT_TX_WINDOW;
 517	chan->sec_level = BT_SECURITY_LOW;
 518	chan->flush_to = L2CAP_DEFAULT_FLUSH_TO;
 519	chan->retrans_timeout = L2CAP_DEFAULT_RETRANS_TO;
 520	chan->monitor_timeout = L2CAP_DEFAULT_MONITOR_TO;
 521
 522	chan->conf_state = 0;
 523	set_bit(CONF_NOT_COMPLETE, &chan->conf_state);
 524
 525	set_bit(FLAG_FORCE_ACTIVE, &chan->flags);
 526}
 527EXPORT_SYMBOL_GPL(l2cap_chan_set_defaults);
 528
 529static void l2cap_le_flowctl_init(struct l2cap_chan *chan, u16 tx_credits)
 530{
 531	chan->sdu = NULL;
 532	chan->sdu_last_frag = NULL;
 533	chan->sdu_len = 0;
 534	chan->tx_credits = tx_credits;
 535	/* Derive MPS from connection MTU to stop HCI fragmentation */
 536	chan->mps = min_t(u16, chan->imtu, chan->conn->mtu - L2CAP_HDR_SIZE);
 537	/* Give enough credits for a full packet */
 538	chan->rx_credits = (chan->imtu / chan->mps) + 1;
 539
 540	skb_queue_head_init(&chan->tx_q);
 541}
 542
 543static void l2cap_ecred_init(struct l2cap_chan *chan, u16 tx_credits)
 544{
 545	l2cap_le_flowctl_init(chan, tx_credits);
 546
 547	/* L2CAP implementations shall support a minimum MPS of 64 octets */
 548	if (chan->mps < L2CAP_ECRED_MIN_MPS) {
 549		chan->mps = L2CAP_ECRED_MIN_MPS;
 550		chan->rx_credits = (chan->imtu / chan->mps) + 1;
 551	}
 552}
 553
 554void __l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan)
 555{
 556	BT_DBG("conn %p, psm 0x%2.2x, dcid 0x%4.4x", conn,
 557	       __le16_to_cpu(chan->psm), chan->dcid);
 558
 559	conn->disc_reason = HCI_ERROR_REMOTE_USER_TERM;
 560
 561	chan->conn = conn;
 562
 563	switch (chan->chan_type) {
 564	case L2CAP_CHAN_CONN_ORIENTED:
 565		/* Alloc CID for connection-oriented socket */
 566		chan->scid = l2cap_alloc_cid(conn);
 567		if (conn->hcon->type == ACL_LINK)
 568			chan->omtu = L2CAP_DEFAULT_MTU;
 569		break;
 570
 571	case L2CAP_CHAN_CONN_LESS:
 572		/* Connectionless socket */
 573		chan->scid = L2CAP_CID_CONN_LESS;
 574		chan->dcid = L2CAP_CID_CONN_LESS;
 575		chan->omtu = L2CAP_DEFAULT_MTU;
 576		break;
 577
 578	case L2CAP_CHAN_FIXED:
 579		/* Caller will set CID and CID specific MTU values */
 580		break;
 581
 582	default:
 583		/* Raw socket can send/recv signalling messages only */
 584		chan->scid = L2CAP_CID_SIGNALING;
 585		chan->dcid = L2CAP_CID_SIGNALING;
 586		chan->omtu = L2CAP_DEFAULT_MTU;
 587	}
 588
 589	chan->local_id		= L2CAP_BESTEFFORT_ID;
 590	chan->local_stype	= L2CAP_SERV_BESTEFFORT;
 591	chan->local_msdu	= L2CAP_DEFAULT_MAX_SDU_SIZE;
 592	chan->local_sdu_itime	= L2CAP_DEFAULT_SDU_ITIME;
 593	chan->local_acc_lat	= L2CAP_DEFAULT_ACC_LAT;
 594	chan->local_flush_to	= L2CAP_EFS_DEFAULT_FLUSH_TO;
 595
 596	l2cap_chan_hold(chan);
 597
 598	/* Only keep a reference for fixed channels if they requested it */
 599	if (chan->chan_type != L2CAP_CHAN_FIXED ||
 600	    test_bit(FLAG_HOLD_HCI_CONN, &chan->flags))
 601		hci_conn_hold(conn->hcon);
 602
 603	list_add(&chan->list, &conn->chan_l);
 604}
 605
 606void l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan)
 607{
 608	mutex_lock(&conn->chan_lock);
 609	__l2cap_chan_add(conn, chan);
 610	mutex_unlock(&conn->chan_lock);
 611}
 612
 613void l2cap_chan_del(struct l2cap_chan *chan, int err)
 614{
 615	struct l2cap_conn *conn = chan->conn;
 616
 617	__clear_chan_timer(chan);
 618
 619	BT_DBG("chan %p, conn %p, err %d, state %s", chan, conn, err,
 620	       state_to_string(chan->state));
 621
 622	chan->ops->teardown(chan, err);
 623
 624	if (conn) {
 625		struct amp_mgr *mgr = conn->hcon->amp_mgr;
 626		/* Delete from channel list */
 627		list_del(&chan->list);
 628
 629		l2cap_chan_put(chan);
 630
 631		chan->conn = NULL;
 632
 633		/* Reference was only held for non-fixed channels or
 634		 * fixed channels that explicitly requested it using the
 635		 * FLAG_HOLD_HCI_CONN flag.
 636		 */
 637		if (chan->chan_type != L2CAP_CHAN_FIXED ||
 638		    test_bit(FLAG_HOLD_HCI_CONN, &chan->flags))
 639			hci_conn_drop(conn->hcon);
 640
 641		if (mgr && mgr->bredr_chan == chan)
 642			mgr->bredr_chan = NULL;
 643	}
 644
 645	if (chan->hs_hchan) {
 646		struct hci_chan *hs_hchan = chan->hs_hchan;
 647
 648		BT_DBG("chan %p disconnect hs_hchan %p", chan, hs_hchan);
 649		amp_disconnect_logical_link(hs_hchan);
 650	}
 651
 652	if (test_bit(CONF_NOT_COMPLETE, &chan->conf_state))
 653		return;
 654
 655	switch (chan->mode) {
 656	case L2CAP_MODE_BASIC:
 657		break;
 658
 659	case L2CAP_MODE_LE_FLOWCTL:
 660	case L2CAP_MODE_EXT_FLOWCTL:
 661		skb_queue_purge(&chan->tx_q);
 662		break;
 663
 664	case L2CAP_MODE_ERTM:
 665		__clear_retrans_timer(chan);
 666		__clear_monitor_timer(chan);
 667		__clear_ack_timer(chan);
 668
 669		skb_queue_purge(&chan->srej_q);
 670
 671		l2cap_seq_list_free(&chan->srej_list);
 672		l2cap_seq_list_free(&chan->retrans_list);
 673		fallthrough;
 
 674
 675	case L2CAP_MODE_STREAMING:
 676		skb_queue_purge(&chan->tx_q);
 677		break;
 678	}
 
 
 679}
 680EXPORT_SYMBOL_GPL(l2cap_chan_del);
 681
 682static void __l2cap_chan_list(struct l2cap_conn *conn, l2cap_chan_func_t func,
 683			      void *data)
 684{
 685	struct l2cap_chan *chan;
 686
 687	list_for_each_entry(chan, &conn->chan_l, list) {
 688		func(chan, data);
 689	}
 690}
 691
 692void l2cap_chan_list(struct l2cap_conn *conn, l2cap_chan_func_t func,
 693		     void *data)
 694{
 695	if (!conn)
 696		return;
 697
 698	mutex_lock(&conn->chan_lock);
 699	__l2cap_chan_list(conn, func, data);
 700	mutex_unlock(&conn->chan_lock);
 701}
 702
 703EXPORT_SYMBOL_GPL(l2cap_chan_list);
 704
 705static void l2cap_conn_update_id_addr(struct work_struct *work)
 706{
 707	struct l2cap_conn *conn = container_of(work, struct l2cap_conn,
 708					       id_addr_update_work);
 709	struct hci_conn *hcon = conn->hcon;
 710	struct l2cap_chan *chan;
 711
 712	mutex_lock(&conn->chan_lock);
 713
 714	list_for_each_entry(chan, &conn->chan_l, list) {
 715		l2cap_chan_lock(chan);
 716		bacpy(&chan->dst, &hcon->dst);
 717		chan->dst_type = bdaddr_dst_type(hcon);
 718		l2cap_chan_unlock(chan);
 719	}
 720
 721	mutex_unlock(&conn->chan_lock);
 722}
 723
 724static void l2cap_chan_le_connect_reject(struct l2cap_chan *chan)
 725{
 726	struct l2cap_conn *conn = chan->conn;
 727	struct l2cap_le_conn_rsp rsp;
 728	u16 result;
 729
 730	if (test_bit(FLAG_DEFER_SETUP, &chan->flags))
 731		result = L2CAP_CR_LE_AUTHORIZATION;
 732	else
 733		result = L2CAP_CR_LE_BAD_PSM;
 734
 735	l2cap_state_change(chan, BT_DISCONN);
 736
 737	rsp.dcid    = cpu_to_le16(chan->scid);
 738	rsp.mtu     = cpu_to_le16(chan->imtu);
 739	rsp.mps     = cpu_to_le16(chan->mps);
 740	rsp.credits = cpu_to_le16(chan->rx_credits);
 741	rsp.result  = cpu_to_le16(result);
 742
 743	l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CONN_RSP, sizeof(rsp),
 744		       &rsp);
 745}
 746
 747static void l2cap_chan_ecred_connect_reject(struct l2cap_chan *chan)
 748{
 749	struct l2cap_conn *conn = chan->conn;
 750	struct l2cap_ecred_conn_rsp rsp;
 751	u16 result;
 752
 753	if (test_bit(FLAG_DEFER_SETUP, &chan->flags))
 754		result = L2CAP_CR_LE_AUTHORIZATION;
 755	else
 756		result = L2CAP_CR_LE_BAD_PSM;
 757
 758	l2cap_state_change(chan, BT_DISCONN);
 759
 760	memset(&rsp, 0, sizeof(rsp));
 761
 762	rsp.result  = cpu_to_le16(result);
 763
 764	l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CONN_RSP, sizeof(rsp),
 765		       &rsp);
 766}
 767
 768static void l2cap_chan_connect_reject(struct l2cap_chan *chan)
 769{
 770	struct l2cap_conn *conn = chan->conn;
 771	struct l2cap_conn_rsp rsp;
 772	u16 result;
 773
 774	if (test_bit(FLAG_DEFER_SETUP, &chan->flags))
 775		result = L2CAP_CR_SEC_BLOCK;
 776	else
 777		result = L2CAP_CR_BAD_PSM;
 778
 779	l2cap_state_change(chan, BT_DISCONN);
 780
 781	rsp.scid   = cpu_to_le16(chan->dcid);
 782	rsp.dcid   = cpu_to_le16(chan->scid);
 783	rsp.result = cpu_to_le16(result);
 784	rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
 785
 786	l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP, sizeof(rsp), &rsp);
 787}
 788
 789void l2cap_chan_close(struct l2cap_chan *chan, int reason)
 790{
 791	struct l2cap_conn *conn = chan->conn;
 792
 793	BT_DBG("chan %p state %s", chan, state_to_string(chan->state));
 794
 795	switch (chan->state) {
 796	case BT_LISTEN:
 797		chan->ops->teardown(chan, 0);
 798		break;
 799
 800	case BT_CONNECTED:
 801	case BT_CONFIG:
 802		if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED) {
 803			__set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
 804			l2cap_send_disconn_req(chan, reason);
 805		} else
 806			l2cap_chan_del(chan, reason);
 807		break;
 808
 809	case BT_CONNECT2:
 810		if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED) {
 811			if (conn->hcon->type == ACL_LINK)
 812				l2cap_chan_connect_reject(chan);
 813			else if (conn->hcon->type == LE_LINK) {
 814				switch (chan->mode) {
 815				case L2CAP_MODE_LE_FLOWCTL:
 816					l2cap_chan_le_connect_reject(chan);
 817					break;
 818				case L2CAP_MODE_EXT_FLOWCTL:
 819					l2cap_chan_ecred_connect_reject(chan);
 820					break;
 821				}
 822			}
 823		}
 824
 825		l2cap_chan_del(chan, reason);
 826		break;
 827
 828	case BT_CONNECT:
 829	case BT_DISCONN:
 830		l2cap_chan_del(chan, reason);
 831		break;
 832
 833	default:
 834		chan->ops->teardown(chan, 0);
 835		break;
 836	}
 837}
 838EXPORT_SYMBOL(l2cap_chan_close);
 839
 840static inline u8 l2cap_get_auth_type(struct l2cap_chan *chan)
 841{
 842	switch (chan->chan_type) {
 843	case L2CAP_CHAN_RAW:
 844		switch (chan->sec_level) {
 845		case BT_SECURITY_HIGH:
 846		case BT_SECURITY_FIPS:
 847			return HCI_AT_DEDICATED_BONDING_MITM;
 848		case BT_SECURITY_MEDIUM:
 849			return HCI_AT_DEDICATED_BONDING;
 850		default:
 851			return HCI_AT_NO_BONDING;
 852		}
 853		break;
 854	case L2CAP_CHAN_CONN_LESS:
 855		if (chan->psm == cpu_to_le16(L2CAP_PSM_3DSP)) {
 856			if (chan->sec_level == BT_SECURITY_LOW)
 857				chan->sec_level = BT_SECURITY_SDP;
 858		}
 859		if (chan->sec_level == BT_SECURITY_HIGH ||
 860		    chan->sec_level == BT_SECURITY_FIPS)
 861			return HCI_AT_NO_BONDING_MITM;
 862		else
 863			return HCI_AT_NO_BONDING;
 864		break;
 865	case L2CAP_CHAN_CONN_ORIENTED:
 866		if (chan->psm == cpu_to_le16(L2CAP_PSM_SDP)) {
 867			if (chan->sec_level == BT_SECURITY_LOW)
 868				chan->sec_level = BT_SECURITY_SDP;
 869
 870			if (chan->sec_level == BT_SECURITY_HIGH ||
 871			    chan->sec_level == BT_SECURITY_FIPS)
 872				return HCI_AT_NO_BONDING_MITM;
 873			else
 874				return HCI_AT_NO_BONDING;
 875		}
 876		fallthrough;
 877
 878	default:
 879		switch (chan->sec_level) {
 880		case BT_SECURITY_HIGH:
 881		case BT_SECURITY_FIPS:
 882			return HCI_AT_GENERAL_BONDING_MITM;
 883		case BT_SECURITY_MEDIUM:
 884			return HCI_AT_GENERAL_BONDING;
 885		default:
 886			return HCI_AT_NO_BONDING;
 887		}
 888		break;
 889	}
 890}
 891
 892/* Service level security */
 893int l2cap_chan_check_security(struct l2cap_chan *chan, bool initiator)
 894{
 895	struct l2cap_conn *conn = chan->conn;
 896	__u8 auth_type;
 897
 898	if (conn->hcon->type == LE_LINK)
 899		return smp_conn_security(conn->hcon, chan->sec_level);
 900
 901	auth_type = l2cap_get_auth_type(chan);
 902
 903	return hci_conn_security(conn->hcon, chan->sec_level, auth_type,
 904				 initiator);
 905}
 906
 907static u8 l2cap_get_ident(struct l2cap_conn *conn)
 908{
 909	u8 id;
 910
 911	/* Get next available identificator.
 912	 *    1 - 128 are used by kernel.
 913	 *  129 - 199 are reserved.
 914	 *  200 - 254 are used by utilities like l2ping, etc.
 915	 */
 916
 917	mutex_lock(&conn->ident_lock);
 918
 919	if (++conn->tx_ident > 128)
 920		conn->tx_ident = 1;
 921
 922	id = conn->tx_ident;
 923
 924	mutex_unlock(&conn->ident_lock);
 925
 926	return id;
 927}
 928
 929static void l2cap_send_cmd(struct l2cap_conn *conn, u8 ident, u8 code, u16 len,
 930			   void *data)
 931{
 932	struct sk_buff *skb = l2cap_build_cmd(conn, code, ident, len, data);
 933	u8 flags;
 934
 935	BT_DBG("code 0x%2.2x", code);
 936
 937	if (!skb)
 938		return;
 939
 940	/* Use NO_FLUSH if supported or we have an LE link (which does
 941	 * not support auto-flushing packets) */
 942	if (lmp_no_flush_capable(conn->hcon->hdev) ||
 943	    conn->hcon->type == LE_LINK)
 944		flags = ACL_START_NO_FLUSH;
 945	else
 946		flags = ACL_START;
 947
 948	bt_cb(skb)->force_active = BT_POWER_FORCE_ACTIVE_ON;
 949	skb->priority = HCI_PRIO_MAX;
 950
 951	hci_send_acl(conn->hchan, skb, flags);
 952}
 953
 954static bool __chan_is_moving(struct l2cap_chan *chan)
 955{
 956	return chan->move_state != L2CAP_MOVE_STABLE &&
 957	       chan->move_state != L2CAP_MOVE_WAIT_PREPARE;
 958}
 959
 960static void l2cap_do_send(struct l2cap_chan *chan, struct sk_buff *skb)
 961{
 962	struct hci_conn *hcon = chan->conn->hcon;
 963	u16 flags;
 964
 965	BT_DBG("chan %p, skb %p len %d priority %u", chan, skb, skb->len,
 966	       skb->priority);
 967
 968	if (chan->hs_hcon && !__chan_is_moving(chan)) {
 969		if (chan->hs_hchan)
 970			hci_send_acl(chan->hs_hchan, skb, ACL_COMPLETE);
 971		else
 972			kfree_skb(skb);
 973
 974		return;
 975	}
 976
 977	/* Use NO_FLUSH for LE links (where this is the only option) or
 978	 * if the BR/EDR link supports it and flushing has not been
 979	 * explicitly requested (through FLAG_FLUSHABLE).
 980	 */
 981	if (hcon->type == LE_LINK ||
 982	    (!test_bit(FLAG_FLUSHABLE, &chan->flags) &&
 983	     lmp_no_flush_capable(hcon->hdev)))
 984		flags = ACL_START_NO_FLUSH;
 985	else
 986		flags = ACL_START;
 987
 988	bt_cb(skb)->force_active = test_bit(FLAG_FORCE_ACTIVE, &chan->flags);
 989	hci_send_acl(chan->conn->hchan, skb, flags);
 990}
 991
 992static void __unpack_enhanced_control(u16 enh, struct l2cap_ctrl *control)
 993{
 994	control->reqseq = (enh & L2CAP_CTRL_REQSEQ) >> L2CAP_CTRL_REQSEQ_SHIFT;
 995	control->final = (enh & L2CAP_CTRL_FINAL) >> L2CAP_CTRL_FINAL_SHIFT;
 996
 997	if (enh & L2CAP_CTRL_FRAME_TYPE) {
 998		/* S-Frame */
 999		control->sframe = 1;
1000		control->poll = (enh & L2CAP_CTRL_POLL) >> L2CAP_CTRL_POLL_SHIFT;
1001		control->super = (enh & L2CAP_CTRL_SUPERVISE) >> L2CAP_CTRL_SUPER_SHIFT;
1002
1003		control->sar = 0;
1004		control->txseq = 0;
1005	} else {
1006		/* I-Frame */
1007		control->sframe = 0;
1008		control->sar = (enh & L2CAP_CTRL_SAR) >> L2CAP_CTRL_SAR_SHIFT;
1009		control->txseq = (enh & L2CAP_CTRL_TXSEQ) >> L2CAP_CTRL_TXSEQ_SHIFT;
1010
1011		control->poll = 0;
1012		control->super = 0;
1013	}
1014}
1015
1016static void __unpack_extended_control(u32 ext, struct l2cap_ctrl *control)
1017{
1018	control->reqseq = (ext & L2CAP_EXT_CTRL_REQSEQ) >> L2CAP_EXT_CTRL_REQSEQ_SHIFT;
1019	control->final = (ext & L2CAP_EXT_CTRL_FINAL) >> L2CAP_EXT_CTRL_FINAL_SHIFT;
1020
1021	if (ext & L2CAP_EXT_CTRL_FRAME_TYPE) {
1022		/* S-Frame */
1023		control->sframe = 1;
1024		control->poll = (ext & L2CAP_EXT_CTRL_POLL) >> L2CAP_EXT_CTRL_POLL_SHIFT;
1025		control->super = (ext & L2CAP_EXT_CTRL_SUPERVISE) >> L2CAP_EXT_CTRL_SUPER_SHIFT;
1026
1027		control->sar = 0;
1028		control->txseq = 0;
1029	} else {
1030		/* I-Frame */
1031		control->sframe = 0;
1032		control->sar = (ext & L2CAP_EXT_CTRL_SAR) >> L2CAP_EXT_CTRL_SAR_SHIFT;
1033		control->txseq = (ext & L2CAP_EXT_CTRL_TXSEQ) >> L2CAP_EXT_CTRL_TXSEQ_SHIFT;
1034
1035		control->poll = 0;
1036		control->super = 0;
1037	}
1038}
1039
1040static inline void __unpack_control(struct l2cap_chan *chan,
1041				    struct sk_buff *skb)
1042{
1043	if (test_bit(FLAG_EXT_CTRL, &chan->flags)) {
1044		__unpack_extended_control(get_unaligned_le32(skb->data),
1045					  &bt_cb(skb)->l2cap);
1046		skb_pull(skb, L2CAP_EXT_CTRL_SIZE);
1047	} else {
1048		__unpack_enhanced_control(get_unaligned_le16(skb->data),
1049					  &bt_cb(skb)->l2cap);
1050		skb_pull(skb, L2CAP_ENH_CTRL_SIZE);
1051	}
1052}
1053
1054static u32 __pack_extended_control(struct l2cap_ctrl *control)
1055{
1056	u32 packed;
1057
1058	packed = control->reqseq << L2CAP_EXT_CTRL_REQSEQ_SHIFT;
1059	packed |= control->final << L2CAP_EXT_CTRL_FINAL_SHIFT;
1060
1061	if (control->sframe) {
1062		packed |= control->poll << L2CAP_EXT_CTRL_POLL_SHIFT;
1063		packed |= control->super << L2CAP_EXT_CTRL_SUPER_SHIFT;
1064		packed |= L2CAP_EXT_CTRL_FRAME_TYPE;
1065	} else {
1066		packed |= control->sar << L2CAP_EXT_CTRL_SAR_SHIFT;
1067		packed |= control->txseq << L2CAP_EXT_CTRL_TXSEQ_SHIFT;
1068	}
1069
1070	return packed;
1071}
1072
1073static u16 __pack_enhanced_control(struct l2cap_ctrl *control)
1074{
1075	u16 packed;
1076
1077	packed = control->reqseq << L2CAP_CTRL_REQSEQ_SHIFT;
1078	packed |= control->final << L2CAP_CTRL_FINAL_SHIFT;
1079
1080	if (control->sframe) {
1081		packed |= control->poll << L2CAP_CTRL_POLL_SHIFT;
1082		packed |= control->super << L2CAP_CTRL_SUPER_SHIFT;
1083		packed |= L2CAP_CTRL_FRAME_TYPE;
1084	} else {
1085		packed |= control->sar << L2CAP_CTRL_SAR_SHIFT;
1086		packed |= control->txseq << L2CAP_CTRL_TXSEQ_SHIFT;
1087	}
1088
1089	return packed;
1090}
1091
1092static inline void __pack_control(struct l2cap_chan *chan,
1093				  struct l2cap_ctrl *control,
1094				  struct sk_buff *skb)
1095{
1096	if (test_bit(FLAG_EXT_CTRL, &chan->flags)) {
1097		put_unaligned_le32(__pack_extended_control(control),
1098				   skb->data + L2CAP_HDR_SIZE);
1099	} else {
1100		put_unaligned_le16(__pack_enhanced_control(control),
1101				   skb->data + L2CAP_HDR_SIZE);
1102	}
1103}
1104
1105static inline unsigned int __ertm_hdr_size(struct l2cap_chan *chan)
1106{
1107	if (test_bit(FLAG_EXT_CTRL, &chan->flags))
1108		return L2CAP_EXT_HDR_SIZE;
1109	else
1110		return L2CAP_ENH_HDR_SIZE;
1111}
1112
1113static struct sk_buff *l2cap_create_sframe_pdu(struct l2cap_chan *chan,
1114					       u32 control)
1115{
1116	struct sk_buff *skb;
1117	struct l2cap_hdr *lh;
1118	int hlen = __ertm_hdr_size(chan);
1119
1120	if (chan->fcs == L2CAP_FCS_CRC16)
1121		hlen += L2CAP_FCS_SIZE;
1122
1123	skb = bt_skb_alloc(hlen, GFP_KERNEL);
1124
1125	if (!skb)
1126		return ERR_PTR(-ENOMEM);
1127
1128	lh = skb_put(skb, L2CAP_HDR_SIZE);
1129	lh->len = cpu_to_le16(hlen - L2CAP_HDR_SIZE);
1130	lh->cid = cpu_to_le16(chan->dcid);
1131
1132	if (test_bit(FLAG_EXT_CTRL, &chan->flags))
1133		put_unaligned_le32(control, skb_put(skb, L2CAP_EXT_CTRL_SIZE));
1134	else
1135		put_unaligned_le16(control, skb_put(skb, L2CAP_ENH_CTRL_SIZE));
1136
1137	if (chan->fcs == L2CAP_FCS_CRC16) {
1138		u16 fcs = crc16(0, (u8 *)skb->data, skb->len);
1139		put_unaligned_le16(fcs, skb_put(skb, L2CAP_FCS_SIZE));
1140	}
1141
1142	skb->priority = HCI_PRIO_MAX;
1143	return skb;
1144}
1145
1146static void l2cap_send_sframe(struct l2cap_chan *chan,
1147			      struct l2cap_ctrl *control)
1148{
1149	struct sk_buff *skb;
1150	u32 control_field;
1151
1152	BT_DBG("chan %p, control %p", chan, control);
1153
1154	if (!control->sframe)
1155		return;
1156
1157	if (__chan_is_moving(chan))
1158		return;
1159
1160	if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state) &&
1161	    !control->poll)
1162		control->final = 1;
1163
1164	if (control->super == L2CAP_SUPER_RR)
1165		clear_bit(CONN_RNR_SENT, &chan->conn_state);
1166	else if (control->super == L2CAP_SUPER_RNR)
1167		set_bit(CONN_RNR_SENT, &chan->conn_state);
1168
1169	if (control->super != L2CAP_SUPER_SREJ) {
1170		chan->last_acked_seq = control->reqseq;
1171		__clear_ack_timer(chan);
1172	}
1173
1174	BT_DBG("reqseq %d, final %d, poll %d, super %d", control->reqseq,
1175	       control->final, control->poll, control->super);
1176
1177	if (test_bit(FLAG_EXT_CTRL, &chan->flags))
1178		control_field = __pack_extended_control(control);
1179	else
1180		control_field = __pack_enhanced_control(control);
1181
1182	skb = l2cap_create_sframe_pdu(chan, control_field);
1183	if (!IS_ERR(skb))
1184		l2cap_do_send(chan, skb);
1185}
1186
1187static void l2cap_send_rr_or_rnr(struct l2cap_chan *chan, bool poll)
1188{
1189	struct l2cap_ctrl control;
1190
1191	BT_DBG("chan %p, poll %d", chan, poll);
1192
1193	memset(&control, 0, sizeof(control));
1194	control.sframe = 1;
1195	control.poll = poll;
1196
1197	if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state))
1198		control.super = L2CAP_SUPER_RNR;
1199	else
1200		control.super = L2CAP_SUPER_RR;
1201
1202	control.reqseq = chan->buffer_seq;
1203	l2cap_send_sframe(chan, &control);
1204}
1205
1206static inline int __l2cap_no_conn_pending(struct l2cap_chan *chan)
1207{
1208	if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED)
1209		return true;
1210
1211	return !test_bit(CONF_CONNECT_PEND, &chan->conf_state);
1212}
1213
1214static bool __amp_capable(struct l2cap_chan *chan)
1215{
1216	struct l2cap_conn *conn = chan->conn;
1217	struct hci_dev *hdev;
1218	bool amp_available = false;
1219
1220	if (!(conn->local_fixed_chan & L2CAP_FC_A2MP))
1221		return false;
1222
1223	if (!(conn->remote_fixed_chan & L2CAP_FC_A2MP))
1224		return false;
1225
1226	read_lock(&hci_dev_list_lock);
1227	list_for_each_entry(hdev, &hci_dev_list, list) {
1228		if (hdev->amp_type != AMP_TYPE_BREDR &&
1229		    test_bit(HCI_UP, &hdev->flags)) {
1230			amp_available = true;
1231			break;
1232		}
1233	}
1234	read_unlock(&hci_dev_list_lock);
1235
1236	if (chan->chan_policy == BT_CHANNEL_POLICY_AMP_PREFERRED)
1237		return amp_available;
1238
1239	return false;
1240}
1241
1242static bool l2cap_check_efs(struct l2cap_chan *chan)
1243{
1244	/* Check EFS parameters */
1245	return true;
1246}
1247
1248void l2cap_send_conn_req(struct l2cap_chan *chan)
1249{
1250	struct l2cap_conn *conn = chan->conn;
1251	struct l2cap_conn_req req;
1252
1253	req.scid = cpu_to_le16(chan->scid);
1254	req.psm  = chan->psm;
1255
1256	chan->ident = l2cap_get_ident(conn);
1257
1258	set_bit(CONF_CONNECT_PEND, &chan->conf_state);
1259
1260	l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_REQ, sizeof(req), &req);
1261}
1262
1263static void l2cap_send_create_chan_req(struct l2cap_chan *chan, u8 amp_id)
1264{
1265	struct l2cap_create_chan_req req;
1266	req.scid = cpu_to_le16(chan->scid);
1267	req.psm  = chan->psm;
1268	req.amp_id = amp_id;
1269
1270	chan->ident = l2cap_get_ident(chan->conn);
1271
1272	l2cap_send_cmd(chan->conn, chan->ident, L2CAP_CREATE_CHAN_REQ,
1273		       sizeof(req), &req);
1274}
1275
1276static void l2cap_move_setup(struct l2cap_chan *chan)
1277{
1278	struct sk_buff *skb;
1279
1280	BT_DBG("chan %p", chan);
1281
1282	if (chan->mode != L2CAP_MODE_ERTM)
1283		return;
1284
1285	__clear_retrans_timer(chan);
1286	__clear_monitor_timer(chan);
1287	__clear_ack_timer(chan);
1288
1289	chan->retry_count = 0;
1290	skb_queue_walk(&chan->tx_q, skb) {
1291		if (bt_cb(skb)->l2cap.retries)
1292			bt_cb(skb)->l2cap.retries = 1;
1293		else
1294			break;
1295	}
1296
1297	chan->expected_tx_seq = chan->buffer_seq;
1298
1299	clear_bit(CONN_REJ_ACT, &chan->conn_state);
1300	clear_bit(CONN_SREJ_ACT, &chan->conn_state);
1301	l2cap_seq_list_clear(&chan->retrans_list);
1302	l2cap_seq_list_clear(&chan->srej_list);
1303	skb_queue_purge(&chan->srej_q);
1304
1305	chan->tx_state = L2CAP_TX_STATE_XMIT;
1306	chan->rx_state = L2CAP_RX_STATE_MOVE;
1307
1308	set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
1309}
1310
1311static void l2cap_move_done(struct l2cap_chan *chan)
1312{
1313	u8 move_role = chan->move_role;
1314	BT_DBG("chan %p", chan);
1315
1316	chan->move_state = L2CAP_MOVE_STABLE;
1317	chan->move_role = L2CAP_MOVE_ROLE_NONE;
1318
1319	if (chan->mode != L2CAP_MODE_ERTM)
1320		return;
1321
1322	switch (move_role) {
1323	case L2CAP_MOVE_ROLE_INITIATOR:
1324		l2cap_tx(chan, NULL, NULL, L2CAP_EV_EXPLICIT_POLL);
1325		chan->rx_state = L2CAP_RX_STATE_WAIT_F;
1326		break;
1327	case L2CAP_MOVE_ROLE_RESPONDER:
1328		chan->rx_state = L2CAP_RX_STATE_WAIT_P;
1329		break;
1330	}
1331}
1332
1333static void l2cap_chan_ready(struct l2cap_chan *chan)
1334{
1335	/* The channel may have already been flagged as connected in
1336	 * case of receiving data before the L2CAP info req/rsp
1337	 * procedure is complete.
1338	 */
1339	if (chan->state == BT_CONNECTED)
1340		return;
1341
1342	/* This clears all conf flags, including CONF_NOT_COMPLETE */
1343	chan->conf_state = 0;
1344	__clear_chan_timer(chan);
1345
1346	switch (chan->mode) {
1347	case L2CAP_MODE_LE_FLOWCTL:
1348	case L2CAP_MODE_EXT_FLOWCTL:
1349		if (!chan->tx_credits)
1350			chan->ops->suspend(chan);
1351		break;
1352	}
1353
1354	chan->state = BT_CONNECTED;
1355
1356	chan->ops->ready(chan);
1357}
1358
1359static void l2cap_le_connect(struct l2cap_chan *chan)
1360{
1361	struct l2cap_conn *conn = chan->conn;
1362	struct l2cap_le_conn_req req;
1363
1364	if (test_and_set_bit(FLAG_LE_CONN_REQ_SENT, &chan->flags))
1365		return;
1366
1367	if (!chan->imtu)
1368		chan->imtu = chan->conn->mtu;
1369
1370	l2cap_le_flowctl_init(chan, 0);
1371
1372	req.psm     = chan->psm;
1373	req.scid    = cpu_to_le16(chan->scid);
1374	req.mtu     = cpu_to_le16(chan->imtu);
1375	req.mps     = cpu_to_le16(chan->mps);
1376	req.credits = cpu_to_le16(chan->rx_credits);
1377
1378	chan->ident = l2cap_get_ident(conn);
1379
1380	l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CONN_REQ,
1381		       sizeof(req), &req);
1382}
1383
1384struct l2cap_ecred_conn_data {
1385	struct {
1386		struct l2cap_ecred_conn_req req;
1387		__le16 scid[5];
1388	} __packed pdu;
1389	struct l2cap_chan *chan;
1390	struct pid *pid;
1391	int count;
1392};
1393
1394static void l2cap_ecred_defer_connect(struct l2cap_chan *chan, void *data)
1395{
1396	struct l2cap_ecred_conn_data *conn = data;
1397	struct pid *pid;
1398
1399	if (chan == conn->chan)
1400		return;
1401
1402	if (!test_and_clear_bit(FLAG_DEFER_SETUP, &chan->flags))
1403		return;
1404
1405	pid = chan->ops->get_peer_pid(chan);
1406
1407	/* Only add deferred channels with the same PID/PSM */
1408	if (conn->pid != pid || chan->psm != conn->chan->psm || chan->ident ||
1409	    chan->mode != L2CAP_MODE_EXT_FLOWCTL || chan->state != BT_CONNECT)
1410		return;
1411
1412	if (test_and_set_bit(FLAG_ECRED_CONN_REQ_SENT, &chan->flags))
1413		return;
1414
1415	l2cap_ecred_init(chan, 0);
1416
1417	/* Set the same ident so we can match on the rsp */
1418	chan->ident = conn->chan->ident;
1419
1420	/* Include all channels deferred */
1421	conn->pdu.scid[conn->count] = cpu_to_le16(chan->scid);
1422
1423	conn->count++;
1424}
1425
1426static void l2cap_ecred_connect(struct l2cap_chan *chan)
1427{
1428	struct l2cap_conn *conn = chan->conn;
1429	struct l2cap_ecred_conn_data data;
1430
1431	if (test_bit(FLAG_DEFER_SETUP, &chan->flags))
1432		return;
1433
1434	if (test_and_set_bit(FLAG_ECRED_CONN_REQ_SENT, &chan->flags))
1435		return;
1436
1437	l2cap_ecred_init(chan, 0);
1438
1439	data.pdu.req.psm     = chan->psm;
1440	data.pdu.req.mtu     = cpu_to_le16(chan->imtu);
1441	data.pdu.req.mps     = cpu_to_le16(chan->mps);
1442	data.pdu.req.credits = cpu_to_le16(chan->rx_credits);
1443	data.pdu.scid[0]     = cpu_to_le16(chan->scid);
1444
1445	chan->ident = l2cap_get_ident(conn);
1446	data.pid = chan->ops->get_peer_pid(chan);
1447
1448	data.count = 1;
1449	data.chan = chan;
1450	data.pid = chan->ops->get_peer_pid(chan);
1451
1452	__l2cap_chan_list(conn, l2cap_ecred_defer_connect, &data);
1453
1454	l2cap_send_cmd(conn, chan->ident, L2CAP_ECRED_CONN_REQ,
1455		       sizeof(data.pdu.req) + data.count * sizeof(__le16),
1456		       &data.pdu);
1457}
1458
1459static void l2cap_le_start(struct l2cap_chan *chan)
1460{
1461	struct l2cap_conn *conn = chan->conn;
1462
1463	if (!smp_conn_security(conn->hcon, chan->sec_level))
1464		return;
1465
1466	if (!chan->psm) {
1467		l2cap_chan_ready(chan);
1468		return;
1469	}
1470
1471	if (chan->state == BT_CONNECT) {
1472		if (chan->mode == L2CAP_MODE_EXT_FLOWCTL)
1473			l2cap_ecred_connect(chan);
1474		else
1475			l2cap_le_connect(chan);
1476	}
1477}
1478
1479static void l2cap_start_connection(struct l2cap_chan *chan)
1480{
1481	if (__amp_capable(chan)) {
1482		BT_DBG("chan %p AMP capable: discover AMPs", chan);
1483		a2mp_discover_amp(chan);
1484	} else if (chan->conn->hcon->type == LE_LINK) {
1485		l2cap_le_start(chan);
1486	} else {
1487		l2cap_send_conn_req(chan);
1488	}
1489}
1490
1491static void l2cap_request_info(struct l2cap_conn *conn)
1492{
1493	struct l2cap_info_req req;
1494
1495	if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT)
1496		return;
1497
1498	req.type = cpu_to_le16(L2CAP_IT_FEAT_MASK);
1499
1500	conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_SENT;
1501	conn->info_ident = l2cap_get_ident(conn);
1502
1503	schedule_delayed_work(&conn->info_timer, L2CAP_INFO_TIMEOUT);
1504
1505	l2cap_send_cmd(conn, conn->info_ident, L2CAP_INFO_REQ,
1506		       sizeof(req), &req);
1507}
1508
1509static bool l2cap_check_enc_key_size(struct hci_conn *hcon)
1510{
1511	/* The minimum encryption key size needs to be enforced by the
1512	 * host stack before establishing any L2CAP connections. The
1513	 * specification in theory allows a minimum of 1, but to align
1514	 * BR/EDR and LE transports, a minimum of 7 is chosen.
1515	 *
1516	 * This check might also be called for unencrypted connections
1517	 * that have no key size requirements. Ensure that the link is
1518	 * actually encrypted before enforcing a key size.
1519	 */
1520	int min_key_size = hcon->hdev->min_enc_key_size;
1521
1522	/* On FIPS security level, key size must be 16 bytes */
1523	if (hcon->sec_level == BT_SECURITY_FIPS)
1524		min_key_size = 16;
1525
1526	return (!test_bit(HCI_CONN_ENCRYPT, &hcon->flags) ||
1527		hcon->enc_key_size >= min_key_size);
1528}
1529
1530static void l2cap_do_start(struct l2cap_chan *chan)
1531{
1532	struct l2cap_conn *conn = chan->conn;
1533
1534	if (conn->hcon->type == LE_LINK) {
1535		l2cap_le_start(chan);
1536		return;
1537	}
1538
1539	if (!(conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT)) {
1540		l2cap_request_info(conn);
1541		return;
1542	}
1543
1544	if (!(conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE))
1545		return;
1546
1547	if (!l2cap_chan_check_security(chan, true) ||
1548	    !__l2cap_no_conn_pending(chan))
1549		return;
1550
1551	if (l2cap_check_enc_key_size(conn->hcon))
1552		l2cap_start_connection(chan);
1553	else
1554		__set_chan_timer(chan, L2CAP_DISC_TIMEOUT);
1555}
1556
1557static inline int l2cap_mode_supported(__u8 mode, __u32 feat_mask)
1558{
1559	u32 local_feat_mask = l2cap_feat_mask;
1560	if (!disable_ertm)
1561		local_feat_mask |= L2CAP_FEAT_ERTM | L2CAP_FEAT_STREAMING;
1562
1563	switch (mode) {
1564	case L2CAP_MODE_ERTM:
1565		return L2CAP_FEAT_ERTM & feat_mask & local_feat_mask;
1566	case L2CAP_MODE_STREAMING:
1567		return L2CAP_FEAT_STREAMING & feat_mask & local_feat_mask;
1568	default:
1569		return 0x00;
1570	}
1571}
1572
1573static void l2cap_send_disconn_req(struct l2cap_chan *chan, int err)
1574{
1575	struct l2cap_conn *conn = chan->conn;
1576	struct l2cap_disconn_req req;
1577
1578	if (!conn)
1579		return;
1580
1581	if (chan->mode == L2CAP_MODE_ERTM && chan->state == BT_CONNECTED) {
1582		__clear_retrans_timer(chan);
1583		__clear_monitor_timer(chan);
1584		__clear_ack_timer(chan);
1585	}
1586
1587	if (chan->scid == L2CAP_CID_A2MP) {
1588		l2cap_state_change(chan, BT_DISCONN);
1589		return;
1590	}
1591
1592	req.dcid = cpu_to_le16(chan->dcid);
1593	req.scid = cpu_to_le16(chan->scid);
1594	l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_DISCONN_REQ,
1595		       sizeof(req), &req);
1596
1597	l2cap_state_change_and_error(chan, BT_DISCONN, err);
1598}
1599
1600/* ---- L2CAP connections ---- */
1601static void l2cap_conn_start(struct l2cap_conn *conn)
1602{
1603	struct l2cap_chan *chan, *tmp;
1604
1605	BT_DBG("conn %p", conn);
1606
1607	mutex_lock(&conn->chan_lock);
1608
1609	list_for_each_entry_safe(chan, tmp, &conn->chan_l, list) {
1610		l2cap_chan_lock(chan);
1611
1612		if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
1613			l2cap_chan_ready(chan);
1614			l2cap_chan_unlock(chan);
1615			continue;
1616		}
1617
1618		if (chan->state == BT_CONNECT) {
1619			if (!l2cap_chan_check_security(chan, true) ||
1620			    !__l2cap_no_conn_pending(chan)) {
1621				l2cap_chan_unlock(chan);
1622				continue;
1623			}
1624
1625			if (!l2cap_mode_supported(chan->mode, conn->feat_mask)
1626			    && test_bit(CONF_STATE2_DEVICE,
1627					&chan->conf_state)) {
1628				l2cap_chan_close(chan, ECONNRESET);
1629				l2cap_chan_unlock(chan);
1630				continue;
1631			}
1632
1633			if (l2cap_check_enc_key_size(conn->hcon))
1634				l2cap_start_connection(chan);
1635			else
1636				l2cap_chan_close(chan, ECONNREFUSED);
1637
1638		} else if (chan->state == BT_CONNECT2) {
1639			struct l2cap_conn_rsp rsp;
1640			char buf[128];
1641			rsp.scid = cpu_to_le16(chan->dcid);
1642			rsp.dcid = cpu_to_le16(chan->scid);
1643
1644			if (l2cap_chan_check_security(chan, false)) {
1645				if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
1646					rsp.result = cpu_to_le16(L2CAP_CR_PEND);
1647					rsp.status = cpu_to_le16(L2CAP_CS_AUTHOR_PEND);
1648					chan->ops->defer(chan);
1649
1650				} else {
1651					l2cap_state_change(chan, BT_CONFIG);
1652					rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
1653					rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
1654				}
1655			} else {
1656				rsp.result = cpu_to_le16(L2CAP_CR_PEND);
1657				rsp.status = cpu_to_le16(L2CAP_CS_AUTHEN_PEND);
1658			}
1659
1660			l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP,
1661				       sizeof(rsp), &rsp);
1662
1663			if (test_bit(CONF_REQ_SENT, &chan->conf_state) ||
1664			    rsp.result != L2CAP_CR_SUCCESS) {
1665				l2cap_chan_unlock(chan);
1666				continue;
1667			}
1668
1669			set_bit(CONF_REQ_SENT, &chan->conf_state);
1670			l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
1671				       l2cap_build_conf_req(chan, buf, sizeof(buf)), buf);
1672			chan->num_conf_req++;
1673		}
1674
1675		l2cap_chan_unlock(chan);
1676	}
1677
1678	mutex_unlock(&conn->chan_lock);
1679}
1680
1681static void l2cap_le_conn_ready(struct l2cap_conn *conn)
1682{
1683	struct hci_conn *hcon = conn->hcon;
1684	struct hci_dev *hdev = hcon->hdev;
1685
1686	BT_DBG("%s conn %p", hdev->name, conn);
1687
1688	/* For outgoing pairing which doesn't necessarily have an
1689	 * associated socket (e.g. mgmt_pair_device).
1690	 */
1691	if (hcon->out)
1692		smp_conn_security(hcon, hcon->pending_sec_level);
1693
1694	/* For LE peripheral connections, make sure the connection interval
1695	 * is in the range of the minimum and maximum interval that has
1696	 * been configured for this connection. If not, then trigger
1697	 * the connection update procedure.
1698	 */
1699	if (hcon->role == HCI_ROLE_SLAVE &&
1700	    (hcon->le_conn_interval < hcon->le_conn_min_interval ||
1701	     hcon->le_conn_interval > hcon->le_conn_max_interval)) {
1702		struct l2cap_conn_param_update_req req;
1703
1704		req.min = cpu_to_le16(hcon->le_conn_min_interval);
1705		req.max = cpu_to_le16(hcon->le_conn_max_interval);
1706		req.latency = cpu_to_le16(hcon->le_conn_latency);
1707		req.to_multiplier = cpu_to_le16(hcon->le_supv_timeout);
1708
1709		l2cap_send_cmd(conn, l2cap_get_ident(conn),
1710			       L2CAP_CONN_PARAM_UPDATE_REQ, sizeof(req), &req);
1711	}
1712}
1713
1714static void l2cap_conn_ready(struct l2cap_conn *conn)
1715{
1716	struct l2cap_chan *chan;
1717	struct hci_conn *hcon = conn->hcon;
1718
1719	BT_DBG("conn %p", conn);
1720
1721	if (hcon->type == ACL_LINK)
1722		l2cap_request_info(conn);
1723
1724	mutex_lock(&conn->chan_lock);
1725
1726	list_for_each_entry(chan, &conn->chan_l, list) {
1727
1728		l2cap_chan_lock(chan);
1729
1730		if (chan->scid == L2CAP_CID_A2MP) {
1731			l2cap_chan_unlock(chan);
1732			continue;
1733		}
1734
1735		if (hcon->type == LE_LINK) {
1736			l2cap_le_start(chan);
1737		} else if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
1738			if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE)
1739				l2cap_chan_ready(chan);
1740		} else if (chan->state == BT_CONNECT) {
1741			l2cap_do_start(chan);
1742		}
1743
1744		l2cap_chan_unlock(chan);
1745	}
1746
1747	mutex_unlock(&conn->chan_lock);
1748
1749	if (hcon->type == LE_LINK)
1750		l2cap_le_conn_ready(conn);
1751
1752	queue_work(hcon->hdev->workqueue, &conn->pending_rx_work);
1753}
1754
1755/* Notify sockets that we cannot guaranty reliability anymore */
1756static void l2cap_conn_unreliable(struct l2cap_conn *conn, int err)
1757{
1758	struct l2cap_chan *chan;
1759
1760	BT_DBG("conn %p", conn);
1761
1762	mutex_lock(&conn->chan_lock);
1763
1764	list_for_each_entry(chan, &conn->chan_l, list) {
1765		if (test_bit(FLAG_FORCE_RELIABLE, &chan->flags))
1766			l2cap_chan_set_err(chan, err);
1767	}
1768
1769	mutex_unlock(&conn->chan_lock);
1770}
1771
1772static void l2cap_info_timeout(struct work_struct *work)
1773{
1774	struct l2cap_conn *conn = container_of(work, struct l2cap_conn,
1775					       info_timer.work);
1776
1777	conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
1778	conn->info_ident = 0;
1779
1780	l2cap_conn_start(conn);
1781}
1782
1783/*
1784 * l2cap_user
1785 * External modules can register l2cap_user objects on l2cap_conn. The ->probe
1786 * callback is called during registration. The ->remove callback is called
1787 * during unregistration.
1788 * An l2cap_user object can either be explicitly unregistered or when the
1789 * underlying l2cap_conn object is deleted. This guarantees that l2cap->hcon,
1790 * l2cap->hchan, .. are valid as long as the remove callback hasn't been called.
1791 * External modules must own a reference to the l2cap_conn object if they intend
1792 * to call l2cap_unregister_user(). The l2cap_conn object might get destroyed at
1793 * any time if they don't.
1794 */
1795
1796int l2cap_register_user(struct l2cap_conn *conn, struct l2cap_user *user)
1797{
1798	struct hci_dev *hdev = conn->hcon->hdev;
1799	int ret;
1800
1801	/* We need to check whether l2cap_conn is registered. If it is not, we
1802	 * must not register the l2cap_user. l2cap_conn_del() is unregisters
1803	 * l2cap_conn objects, but doesn't provide its own locking. Instead, it
1804	 * relies on the parent hci_conn object to be locked. This itself relies
1805	 * on the hci_dev object to be locked. So we must lock the hci device
1806	 * here, too. */
1807
1808	hci_dev_lock(hdev);
1809
1810	if (!list_empty(&user->list)) {
1811		ret = -EINVAL;
1812		goto out_unlock;
1813	}
1814
1815	/* conn->hchan is NULL after l2cap_conn_del() was called */
1816	if (!conn->hchan) {
1817		ret = -ENODEV;
1818		goto out_unlock;
1819	}
1820
1821	ret = user->probe(conn, user);
1822	if (ret)
1823		goto out_unlock;
1824
1825	list_add(&user->list, &conn->users);
1826	ret = 0;
1827
1828out_unlock:
1829	hci_dev_unlock(hdev);
1830	return ret;
1831}
1832EXPORT_SYMBOL(l2cap_register_user);
1833
1834void l2cap_unregister_user(struct l2cap_conn *conn, struct l2cap_user *user)
1835{
1836	struct hci_dev *hdev = conn->hcon->hdev;
1837
1838	hci_dev_lock(hdev);
1839
1840	if (list_empty(&user->list))
1841		goto out_unlock;
1842
1843	list_del_init(&user->list);
1844	user->remove(conn, user);
1845
1846out_unlock:
1847	hci_dev_unlock(hdev);
1848}
1849EXPORT_SYMBOL(l2cap_unregister_user);
1850
1851static void l2cap_unregister_all_users(struct l2cap_conn *conn)
1852{
1853	struct l2cap_user *user;
1854
1855	while (!list_empty(&conn->users)) {
1856		user = list_first_entry(&conn->users, struct l2cap_user, list);
1857		list_del_init(&user->list);
1858		user->remove(conn, user);
1859	}
1860}
1861
1862static void l2cap_conn_del(struct hci_conn *hcon, int err)
1863{
1864	struct l2cap_conn *conn = hcon->l2cap_data;
1865	struct l2cap_chan *chan, *l;
1866
1867	if (!conn)
1868		return;
1869
1870	BT_DBG("hcon %p conn %p, err %d", hcon, conn, err);
1871
1872	kfree_skb(conn->rx_skb);
1873
1874	skb_queue_purge(&conn->pending_rx);
1875
1876	/* We can not call flush_work(&conn->pending_rx_work) here since we
1877	 * might block if we are running on a worker from the same workqueue
1878	 * pending_rx_work is waiting on.
1879	 */
1880	if (work_pending(&conn->pending_rx_work))
1881		cancel_work_sync(&conn->pending_rx_work);
1882
1883	if (work_pending(&conn->id_addr_update_work))
1884		cancel_work_sync(&conn->id_addr_update_work);
1885
1886	l2cap_unregister_all_users(conn);
1887
1888	/* Force the connection to be immediately dropped */
1889	hcon->disc_timeout = 0;
1890
1891	mutex_lock(&conn->chan_lock);
1892
1893	/* Kill channels */
1894	list_for_each_entry_safe(chan, l, &conn->chan_l, list) {
1895		l2cap_chan_hold(chan);
1896		l2cap_chan_lock(chan);
1897
1898		l2cap_chan_del(chan, err);
1899
 
 
1900		chan->ops->close(chan);
1901
1902		l2cap_chan_unlock(chan);
1903		l2cap_chan_put(chan);
1904	}
1905
1906	mutex_unlock(&conn->chan_lock);
1907
1908	hci_chan_del(conn->hchan);
1909
1910	if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT)
1911		cancel_delayed_work_sync(&conn->info_timer);
1912
1913	hcon->l2cap_data = NULL;
1914	conn->hchan = NULL;
1915	l2cap_conn_put(conn);
1916}
1917
1918static void l2cap_conn_free(struct kref *ref)
1919{
1920	struct l2cap_conn *conn = container_of(ref, struct l2cap_conn, ref);
1921
1922	hci_conn_put(conn->hcon);
1923	kfree(conn);
1924}
1925
1926struct l2cap_conn *l2cap_conn_get(struct l2cap_conn *conn)
1927{
1928	kref_get(&conn->ref);
1929	return conn;
1930}
1931EXPORT_SYMBOL(l2cap_conn_get);
1932
1933void l2cap_conn_put(struct l2cap_conn *conn)
1934{
1935	kref_put(&conn->ref, l2cap_conn_free);
1936}
1937EXPORT_SYMBOL(l2cap_conn_put);
1938
1939/* ---- Socket interface ---- */
1940
1941/* Find socket with psm and source / destination bdaddr.
1942 * Returns closest match.
1943 */
1944static struct l2cap_chan *l2cap_global_chan_by_psm(int state, __le16 psm,
1945						   bdaddr_t *src,
1946						   bdaddr_t *dst,
1947						   u8 link_type)
1948{
1949	struct l2cap_chan *c, *c1 = NULL;
1950
1951	read_lock(&chan_list_lock);
1952
1953	list_for_each_entry(c, &chan_list, global_l) {
1954		if (state && c->state != state)
1955			continue;
1956
1957		if (link_type == ACL_LINK && c->src_type != BDADDR_BREDR)
1958			continue;
1959
1960		if (link_type == LE_LINK && c->src_type == BDADDR_BREDR)
1961			continue;
1962
1963		if (c->psm == psm) {
1964			int src_match, dst_match;
1965			int src_any, dst_any;
1966
1967			/* Exact match. */
1968			src_match = !bacmp(&c->src, src);
1969			dst_match = !bacmp(&c->dst, dst);
1970			if (src_match && dst_match) {
1971				l2cap_chan_hold(c);
1972				read_unlock(&chan_list_lock);
1973				return c;
1974			}
1975
1976			/* Closest match */
1977			src_any = !bacmp(&c->src, BDADDR_ANY);
1978			dst_any = !bacmp(&c->dst, BDADDR_ANY);
1979			if ((src_match && dst_any) || (src_any && dst_match) ||
1980			    (src_any && dst_any))
1981				c1 = c;
1982		}
1983	}
1984
1985	if (c1)
1986		l2cap_chan_hold(c1);
1987
1988	read_unlock(&chan_list_lock);
1989
1990	return c1;
1991}
1992
1993static void l2cap_monitor_timeout(struct work_struct *work)
1994{
1995	struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
1996					       monitor_timer.work);
1997
1998	BT_DBG("chan %p", chan);
1999
2000	l2cap_chan_lock(chan);
2001
2002	if (!chan->conn) {
2003		l2cap_chan_unlock(chan);
2004		l2cap_chan_put(chan);
2005		return;
2006	}
2007
2008	l2cap_tx(chan, NULL, NULL, L2CAP_EV_MONITOR_TO);
2009
2010	l2cap_chan_unlock(chan);
2011	l2cap_chan_put(chan);
2012}
2013
2014static void l2cap_retrans_timeout(struct work_struct *work)
2015{
2016	struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
2017					       retrans_timer.work);
2018
2019	BT_DBG("chan %p", chan);
2020
2021	l2cap_chan_lock(chan);
2022
2023	if (!chan->conn) {
2024		l2cap_chan_unlock(chan);
2025		l2cap_chan_put(chan);
2026		return;
2027	}
2028
2029	l2cap_tx(chan, NULL, NULL, L2CAP_EV_RETRANS_TO);
2030	l2cap_chan_unlock(chan);
2031	l2cap_chan_put(chan);
2032}
2033
2034static void l2cap_streaming_send(struct l2cap_chan *chan,
2035				 struct sk_buff_head *skbs)
2036{
2037	struct sk_buff *skb;
2038	struct l2cap_ctrl *control;
2039
2040	BT_DBG("chan %p, skbs %p", chan, skbs);
2041
2042	if (__chan_is_moving(chan))
2043		return;
2044
2045	skb_queue_splice_tail_init(skbs, &chan->tx_q);
2046
2047	while (!skb_queue_empty(&chan->tx_q)) {
2048
2049		skb = skb_dequeue(&chan->tx_q);
2050
2051		bt_cb(skb)->l2cap.retries = 1;
2052		control = &bt_cb(skb)->l2cap;
2053
2054		control->reqseq = 0;
2055		control->txseq = chan->next_tx_seq;
2056
2057		__pack_control(chan, control, skb);
2058
2059		if (chan->fcs == L2CAP_FCS_CRC16) {
2060			u16 fcs = crc16(0, (u8 *) skb->data, skb->len);
2061			put_unaligned_le16(fcs, skb_put(skb, L2CAP_FCS_SIZE));
2062		}
2063
2064		l2cap_do_send(chan, skb);
2065
2066		BT_DBG("Sent txseq %u", control->txseq);
2067
2068		chan->next_tx_seq = __next_seq(chan, chan->next_tx_seq);
2069		chan->frames_sent++;
2070	}
2071}
2072
2073static int l2cap_ertm_send(struct l2cap_chan *chan)
2074{
2075	struct sk_buff *skb, *tx_skb;
2076	struct l2cap_ctrl *control;
2077	int sent = 0;
2078
2079	BT_DBG("chan %p", chan);
2080
2081	if (chan->state != BT_CONNECTED)
2082		return -ENOTCONN;
2083
2084	if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state))
2085		return 0;
2086
2087	if (__chan_is_moving(chan))
2088		return 0;
2089
2090	while (chan->tx_send_head &&
2091	       chan->unacked_frames < chan->remote_tx_win &&
2092	       chan->tx_state == L2CAP_TX_STATE_XMIT) {
2093
2094		skb = chan->tx_send_head;
2095
2096		bt_cb(skb)->l2cap.retries = 1;
2097		control = &bt_cb(skb)->l2cap;
2098
2099		if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state))
2100			control->final = 1;
2101
2102		control->reqseq = chan->buffer_seq;
2103		chan->last_acked_seq = chan->buffer_seq;
2104		control->txseq = chan->next_tx_seq;
2105
2106		__pack_control(chan, control, skb);
2107
2108		if (chan->fcs == L2CAP_FCS_CRC16) {
2109			u16 fcs = crc16(0, (u8 *) skb->data, skb->len);
2110			put_unaligned_le16(fcs, skb_put(skb, L2CAP_FCS_SIZE));
2111		}
2112
2113		/* Clone after data has been modified. Data is assumed to be
2114		   read-only (for locking purposes) on cloned sk_buffs.
2115		 */
2116		tx_skb = skb_clone(skb, GFP_KERNEL);
2117
2118		if (!tx_skb)
2119			break;
2120
2121		__set_retrans_timer(chan);
2122
2123		chan->next_tx_seq = __next_seq(chan, chan->next_tx_seq);
2124		chan->unacked_frames++;
2125		chan->frames_sent++;
2126		sent++;
2127
2128		if (skb_queue_is_last(&chan->tx_q, skb))
2129			chan->tx_send_head = NULL;
2130		else
2131			chan->tx_send_head = skb_queue_next(&chan->tx_q, skb);
2132
2133		l2cap_do_send(chan, tx_skb);
2134		BT_DBG("Sent txseq %u", control->txseq);
2135	}
2136
2137	BT_DBG("Sent %d, %u unacked, %u in ERTM queue", sent,
2138	       chan->unacked_frames, skb_queue_len(&chan->tx_q));
2139
2140	return sent;
2141}
2142
2143static void l2cap_ertm_resend(struct l2cap_chan *chan)
2144{
2145	struct l2cap_ctrl control;
2146	struct sk_buff *skb;
2147	struct sk_buff *tx_skb;
2148	u16 seq;
2149
2150	BT_DBG("chan %p", chan);
2151
2152	if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state))
2153		return;
2154
2155	if (__chan_is_moving(chan))
2156		return;
2157
2158	while (chan->retrans_list.head != L2CAP_SEQ_LIST_CLEAR) {
2159		seq = l2cap_seq_list_pop(&chan->retrans_list);
2160
2161		skb = l2cap_ertm_seq_in_queue(&chan->tx_q, seq);
2162		if (!skb) {
2163			BT_DBG("Error: Can't retransmit seq %d, frame missing",
2164			       seq);
2165			continue;
2166		}
2167
2168		bt_cb(skb)->l2cap.retries++;
2169		control = bt_cb(skb)->l2cap;
2170
2171		if (chan->max_tx != 0 &&
2172		    bt_cb(skb)->l2cap.retries > chan->max_tx) {
2173			BT_DBG("Retry limit exceeded (%d)", chan->max_tx);
2174			l2cap_send_disconn_req(chan, ECONNRESET);
2175			l2cap_seq_list_clear(&chan->retrans_list);
2176			break;
2177		}
2178
2179		control.reqseq = chan->buffer_seq;
2180		if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state))
2181			control.final = 1;
2182		else
2183			control.final = 0;
2184
2185		if (skb_cloned(skb)) {
2186			/* Cloned sk_buffs are read-only, so we need a
2187			 * writeable copy
2188			 */
2189			tx_skb = skb_copy(skb, GFP_KERNEL);
2190		} else {
2191			tx_skb = skb_clone(skb, GFP_KERNEL);
2192		}
2193
2194		if (!tx_skb) {
2195			l2cap_seq_list_clear(&chan->retrans_list);
2196			break;
2197		}
2198
2199		/* Update skb contents */
2200		if (test_bit(FLAG_EXT_CTRL, &chan->flags)) {
2201			put_unaligned_le32(__pack_extended_control(&control),
2202					   tx_skb->data + L2CAP_HDR_SIZE);
2203		} else {
2204			put_unaligned_le16(__pack_enhanced_control(&control),
2205					   tx_skb->data + L2CAP_HDR_SIZE);
2206		}
2207
2208		/* Update FCS */
2209		if (chan->fcs == L2CAP_FCS_CRC16) {
2210			u16 fcs = crc16(0, (u8 *) tx_skb->data,
2211					tx_skb->len - L2CAP_FCS_SIZE);
2212			put_unaligned_le16(fcs, skb_tail_pointer(tx_skb) -
2213						L2CAP_FCS_SIZE);
2214		}
2215
2216		l2cap_do_send(chan, tx_skb);
2217
2218		BT_DBG("Resent txseq %d", control.txseq);
2219
2220		chan->last_acked_seq = chan->buffer_seq;
2221	}
2222}
2223
2224static void l2cap_retransmit(struct l2cap_chan *chan,
2225			     struct l2cap_ctrl *control)
2226{
2227	BT_DBG("chan %p, control %p", chan, control);
2228
2229	l2cap_seq_list_append(&chan->retrans_list, control->reqseq);
2230	l2cap_ertm_resend(chan);
2231}
2232
2233static void l2cap_retransmit_all(struct l2cap_chan *chan,
2234				 struct l2cap_ctrl *control)
2235{
2236	struct sk_buff *skb;
2237
2238	BT_DBG("chan %p, control %p", chan, control);
2239
2240	if (control->poll)
2241		set_bit(CONN_SEND_FBIT, &chan->conn_state);
2242
2243	l2cap_seq_list_clear(&chan->retrans_list);
2244
2245	if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state))
2246		return;
2247
2248	if (chan->unacked_frames) {
2249		skb_queue_walk(&chan->tx_q, skb) {
2250			if (bt_cb(skb)->l2cap.txseq == control->reqseq ||
2251			    skb == chan->tx_send_head)
2252				break;
2253		}
2254
2255		skb_queue_walk_from(&chan->tx_q, skb) {
2256			if (skb == chan->tx_send_head)
2257				break;
2258
2259			l2cap_seq_list_append(&chan->retrans_list,
2260					      bt_cb(skb)->l2cap.txseq);
2261		}
2262
2263		l2cap_ertm_resend(chan);
2264	}
2265}
2266
2267static void l2cap_send_ack(struct l2cap_chan *chan)
2268{
2269	struct l2cap_ctrl control;
2270	u16 frames_to_ack = __seq_offset(chan, chan->buffer_seq,
2271					 chan->last_acked_seq);
2272	int threshold;
2273
2274	BT_DBG("chan %p last_acked_seq %d buffer_seq %d",
2275	       chan, chan->last_acked_seq, chan->buffer_seq);
2276
2277	memset(&control, 0, sizeof(control));
2278	control.sframe = 1;
2279
2280	if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state) &&
2281	    chan->rx_state == L2CAP_RX_STATE_RECV) {
2282		__clear_ack_timer(chan);
2283		control.super = L2CAP_SUPER_RNR;
2284		control.reqseq = chan->buffer_seq;
2285		l2cap_send_sframe(chan, &control);
2286	} else {
2287		if (!test_bit(CONN_REMOTE_BUSY, &chan->conn_state)) {
2288			l2cap_ertm_send(chan);
2289			/* If any i-frames were sent, they included an ack */
2290			if (chan->buffer_seq == chan->last_acked_seq)
2291				frames_to_ack = 0;
2292		}
2293
2294		/* Ack now if the window is 3/4ths full.
2295		 * Calculate without mul or div
2296		 */
2297		threshold = chan->ack_win;
2298		threshold += threshold << 1;
2299		threshold >>= 2;
2300
2301		BT_DBG("frames_to_ack %u, threshold %d", frames_to_ack,
2302		       threshold);
2303
2304		if (frames_to_ack >= threshold) {
2305			__clear_ack_timer(chan);
2306			control.super = L2CAP_SUPER_RR;
2307			control.reqseq = chan->buffer_seq;
2308			l2cap_send_sframe(chan, &control);
2309			frames_to_ack = 0;
2310		}
2311
2312		if (frames_to_ack)
2313			__set_ack_timer(chan);
2314	}
2315}
2316
2317static inline int l2cap_skbuff_fromiovec(struct l2cap_chan *chan,
2318					 struct msghdr *msg, int len,
2319					 int count, struct sk_buff *skb)
2320{
2321	struct l2cap_conn *conn = chan->conn;
2322	struct sk_buff **frag;
2323	int sent = 0;
2324
2325	if (!copy_from_iter_full(skb_put(skb, count), count, &msg->msg_iter))
2326		return -EFAULT;
2327
2328	sent += count;
2329	len  -= count;
2330
2331	/* Continuation fragments (no L2CAP header) */
2332	frag = &skb_shinfo(skb)->frag_list;
2333	while (len) {
2334		struct sk_buff *tmp;
2335
2336		count = min_t(unsigned int, conn->mtu, len);
2337
2338		tmp = chan->ops->alloc_skb(chan, 0, count,
2339					   msg->msg_flags & MSG_DONTWAIT);
2340		if (IS_ERR(tmp))
2341			return PTR_ERR(tmp);
2342
2343		*frag = tmp;
2344
2345		if (!copy_from_iter_full(skb_put(*frag, count), count,
2346				   &msg->msg_iter))
2347			return -EFAULT;
2348
2349		sent += count;
2350		len  -= count;
2351
2352		skb->len += (*frag)->len;
2353		skb->data_len += (*frag)->len;
2354
2355		frag = &(*frag)->next;
2356	}
2357
2358	return sent;
2359}
2360
2361static struct sk_buff *l2cap_create_connless_pdu(struct l2cap_chan *chan,
2362						 struct msghdr *msg, size_t len)
2363{
2364	struct l2cap_conn *conn = chan->conn;
2365	struct sk_buff *skb;
2366	int err, count, hlen = L2CAP_HDR_SIZE + L2CAP_PSMLEN_SIZE;
2367	struct l2cap_hdr *lh;
2368
2369	BT_DBG("chan %p psm 0x%2.2x len %zu", chan,
2370	       __le16_to_cpu(chan->psm), len);
2371
2372	count = min_t(unsigned int, (conn->mtu - hlen), len);
2373
2374	skb = chan->ops->alloc_skb(chan, hlen, count,
2375				   msg->msg_flags & MSG_DONTWAIT);
2376	if (IS_ERR(skb))
2377		return skb;
2378
2379	/* Create L2CAP header */
2380	lh = skb_put(skb, L2CAP_HDR_SIZE);
2381	lh->cid = cpu_to_le16(chan->dcid);
2382	lh->len = cpu_to_le16(len + L2CAP_PSMLEN_SIZE);
2383	put_unaligned(chan->psm, (__le16 *) skb_put(skb, L2CAP_PSMLEN_SIZE));
2384
2385	err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2386	if (unlikely(err < 0)) {
2387		kfree_skb(skb);
2388		return ERR_PTR(err);
2389	}
2390	return skb;
2391}
2392
2393static struct sk_buff *l2cap_create_basic_pdu(struct l2cap_chan *chan,
2394					      struct msghdr *msg, size_t len)
2395{
2396	struct l2cap_conn *conn = chan->conn;
2397	struct sk_buff *skb;
2398	int err, count;
2399	struct l2cap_hdr *lh;
2400
2401	BT_DBG("chan %p len %zu", chan, len);
2402
2403	count = min_t(unsigned int, (conn->mtu - L2CAP_HDR_SIZE), len);
2404
2405	skb = chan->ops->alloc_skb(chan, L2CAP_HDR_SIZE, count,
2406				   msg->msg_flags & MSG_DONTWAIT);
2407	if (IS_ERR(skb))
2408		return skb;
2409
2410	/* Create L2CAP header */
2411	lh = skb_put(skb, L2CAP_HDR_SIZE);
2412	lh->cid = cpu_to_le16(chan->dcid);
2413	lh->len = cpu_to_le16(len);
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	return skb;
2421}
2422
2423static struct sk_buff *l2cap_create_iframe_pdu(struct l2cap_chan *chan,
2424					       struct msghdr *msg, size_t len,
2425					       u16 sdulen)
2426{
2427	struct l2cap_conn *conn = chan->conn;
2428	struct sk_buff *skb;
2429	int err, count, hlen;
2430	struct l2cap_hdr *lh;
2431
2432	BT_DBG("chan %p len %zu", chan, len);
2433
2434	if (!conn)
2435		return ERR_PTR(-ENOTCONN);
2436
2437	hlen = __ertm_hdr_size(chan);
2438
2439	if (sdulen)
2440		hlen += L2CAP_SDULEN_SIZE;
2441
2442	if (chan->fcs == L2CAP_FCS_CRC16)
2443		hlen += L2CAP_FCS_SIZE;
2444
2445	count = min_t(unsigned int, (conn->mtu - hlen), len);
2446
2447	skb = chan->ops->alloc_skb(chan, hlen, count,
2448				   msg->msg_flags & MSG_DONTWAIT);
2449	if (IS_ERR(skb))
2450		return skb;
2451
2452	/* Create L2CAP header */
2453	lh = skb_put(skb, L2CAP_HDR_SIZE);
2454	lh->cid = cpu_to_le16(chan->dcid);
2455	lh->len = cpu_to_le16(len + (hlen - L2CAP_HDR_SIZE));
2456
2457	/* Control header is populated later */
2458	if (test_bit(FLAG_EXT_CTRL, &chan->flags))
2459		put_unaligned_le32(0, skb_put(skb, L2CAP_EXT_CTRL_SIZE));
2460	else
2461		put_unaligned_le16(0, skb_put(skb, L2CAP_ENH_CTRL_SIZE));
2462
2463	if (sdulen)
2464		put_unaligned_le16(sdulen, skb_put(skb, L2CAP_SDULEN_SIZE));
2465
2466	err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2467	if (unlikely(err < 0)) {
2468		kfree_skb(skb);
2469		return ERR_PTR(err);
2470	}
2471
2472	bt_cb(skb)->l2cap.fcs = chan->fcs;
2473	bt_cb(skb)->l2cap.retries = 0;
2474	return skb;
2475}
2476
2477static int l2cap_segment_sdu(struct l2cap_chan *chan,
2478			     struct sk_buff_head *seg_queue,
2479			     struct msghdr *msg, size_t len)
2480{
2481	struct sk_buff *skb;
2482	u16 sdu_len;
2483	size_t pdu_len;
2484	u8 sar;
2485
2486	BT_DBG("chan %p, msg %p, len %zu", chan, msg, len);
2487
2488	/* It is critical that ERTM PDUs fit in a single HCI fragment,
2489	 * so fragmented skbs are not used.  The HCI layer's handling
2490	 * of fragmented skbs is not compatible with ERTM's queueing.
2491	 */
2492
2493	/* PDU size is derived from the HCI MTU */
2494	pdu_len = chan->conn->mtu;
2495
2496	/* Constrain PDU size for BR/EDR connections */
2497	if (!chan->hs_hcon)
2498		pdu_len = min_t(size_t, pdu_len, L2CAP_BREDR_MAX_PAYLOAD);
2499
2500	/* Adjust for largest possible L2CAP overhead. */
2501	if (chan->fcs)
2502		pdu_len -= L2CAP_FCS_SIZE;
2503
2504	pdu_len -= __ertm_hdr_size(chan);
2505
2506	/* Remote device may have requested smaller PDUs */
2507	pdu_len = min_t(size_t, pdu_len, chan->remote_mps);
2508
2509	if (len <= pdu_len) {
2510		sar = L2CAP_SAR_UNSEGMENTED;
2511		sdu_len = 0;
2512		pdu_len = len;
2513	} else {
2514		sar = L2CAP_SAR_START;
2515		sdu_len = len;
2516	}
2517
2518	while (len > 0) {
2519		skb = l2cap_create_iframe_pdu(chan, msg, pdu_len, sdu_len);
2520
2521		if (IS_ERR(skb)) {
2522			__skb_queue_purge(seg_queue);
2523			return PTR_ERR(skb);
2524		}
2525
2526		bt_cb(skb)->l2cap.sar = sar;
2527		__skb_queue_tail(seg_queue, skb);
2528
2529		len -= pdu_len;
2530		if (sdu_len)
2531			sdu_len = 0;
2532
2533		if (len <= pdu_len) {
2534			sar = L2CAP_SAR_END;
2535			pdu_len = len;
2536		} else {
2537			sar = L2CAP_SAR_CONTINUE;
2538		}
2539	}
2540
2541	return 0;
2542}
2543
2544static struct sk_buff *l2cap_create_le_flowctl_pdu(struct l2cap_chan *chan,
2545						   struct msghdr *msg,
2546						   size_t len, u16 sdulen)
2547{
2548	struct l2cap_conn *conn = chan->conn;
2549	struct sk_buff *skb;
2550	int err, count, hlen;
2551	struct l2cap_hdr *lh;
2552
2553	BT_DBG("chan %p len %zu", chan, len);
2554
2555	if (!conn)
2556		return ERR_PTR(-ENOTCONN);
2557
2558	hlen = L2CAP_HDR_SIZE;
2559
2560	if (sdulen)
2561		hlen += L2CAP_SDULEN_SIZE;
2562
2563	count = min_t(unsigned int, (conn->mtu - hlen), len);
2564
2565	skb = chan->ops->alloc_skb(chan, hlen, count,
2566				   msg->msg_flags & MSG_DONTWAIT);
2567	if (IS_ERR(skb))
2568		return skb;
2569
2570	/* Create L2CAP header */
2571	lh = skb_put(skb, L2CAP_HDR_SIZE);
2572	lh->cid = cpu_to_le16(chan->dcid);
2573	lh->len = cpu_to_le16(len + (hlen - L2CAP_HDR_SIZE));
2574
2575	if (sdulen)
2576		put_unaligned_le16(sdulen, skb_put(skb, L2CAP_SDULEN_SIZE));
2577
2578	err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2579	if (unlikely(err < 0)) {
2580		kfree_skb(skb);
2581		return ERR_PTR(err);
2582	}
2583
2584	return skb;
2585}
2586
2587static int l2cap_segment_le_sdu(struct l2cap_chan *chan,
2588				struct sk_buff_head *seg_queue,
2589				struct msghdr *msg, size_t len)
2590{
2591	struct sk_buff *skb;
2592	size_t pdu_len;
2593	u16 sdu_len;
2594
2595	BT_DBG("chan %p, msg %p, len %zu", chan, msg, len);
2596
2597	sdu_len = len;
2598	pdu_len = chan->remote_mps - L2CAP_SDULEN_SIZE;
2599
2600	while (len > 0) {
2601		if (len <= pdu_len)
2602			pdu_len = len;
2603
2604		skb = l2cap_create_le_flowctl_pdu(chan, msg, pdu_len, sdu_len);
2605		if (IS_ERR(skb)) {
2606			__skb_queue_purge(seg_queue);
2607			return PTR_ERR(skb);
2608		}
2609
2610		__skb_queue_tail(seg_queue, skb);
2611
2612		len -= pdu_len;
2613
2614		if (sdu_len) {
2615			sdu_len = 0;
2616			pdu_len += L2CAP_SDULEN_SIZE;
2617		}
2618	}
2619
2620	return 0;
2621}
2622
2623static void l2cap_le_flowctl_send(struct l2cap_chan *chan)
2624{
2625	int sent = 0;
2626
2627	BT_DBG("chan %p", chan);
2628
2629	while (chan->tx_credits && !skb_queue_empty(&chan->tx_q)) {
2630		l2cap_do_send(chan, skb_dequeue(&chan->tx_q));
2631		chan->tx_credits--;
2632		sent++;
2633	}
2634
2635	BT_DBG("Sent %d credits %u queued %u", sent, chan->tx_credits,
2636	       skb_queue_len(&chan->tx_q));
2637}
2638
2639int l2cap_chan_send(struct l2cap_chan *chan, struct msghdr *msg, size_t len)
2640{
2641	struct sk_buff *skb;
2642	int err;
2643	struct sk_buff_head seg_queue;
2644
2645	if (!chan->conn)
2646		return -ENOTCONN;
2647
2648	/* Connectionless channel */
2649	if (chan->chan_type == L2CAP_CHAN_CONN_LESS) {
2650		skb = l2cap_create_connless_pdu(chan, msg, len);
2651		if (IS_ERR(skb))
2652			return PTR_ERR(skb);
2653
2654		/* Channel lock is released before requesting new skb and then
2655		 * reacquired thus we need to recheck channel state.
2656		 */
2657		if (chan->state != BT_CONNECTED) {
2658			kfree_skb(skb);
2659			return -ENOTCONN;
2660		}
2661
2662		l2cap_do_send(chan, skb);
2663		return len;
2664	}
2665
2666	switch (chan->mode) {
2667	case L2CAP_MODE_LE_FLOWCTL:
2668	case L2CAP_MODE_EXT_FLOWCTL:
2669		/* Check outgoing MTU */
2670		if (len > chan->omtu)
2671			return -EMSGSIZE;
2672
 
 
 
2673		__skb_queue_head_init(&seg_queue);
2674
2675		err = l2cap_segment_le_sdu(chan, &seg_queue, msg, len);
2676
2677		if (chan->state != BT_CONNECTED) {
2678			__skb_queue_purge(&seg_queue);
2679			err = -ENOTCONN;
2680		}
2681
2682		if (err)
2683			return err;
2684
2685		skb_queue_splice_tail_init(&seg_queue, &chan->tx_q);
2686
2687		l2cap_le_flowctl_send(chan);
 
 
 
2688
2689		if (!chan->tx_credits)
2690			chan->ops->suspend(chan);
2691
2692		err = len;
2693
2694		break;
2695
2696	case L2CAP_MODE_BASIC:
2697		/* Check outgoing MTU */
2698		if (len > chan->omtu)
2699			return -EMSGSIZE;
2700
2701		/* Create a basic PDU */
2702		skb = l2cap_create_basic_pdu(chan, msg, len);
2703		if (IS_ERR(skb))
2704			return PTR_ERR(skb);
2705
2706		/* Channel lock is released before requesting new skb and then
2707		 * reacquired thus we need to recheck channel state.
2708		 */
2709		if (chan->state != BT_CONNECTED) {
2710			kfree_skb(skb);
2711			return -ENOTCONN;
2712		}
2713
2714		l2cap_do_send(chan, skb);
2715		err = len;
2716		break;
2717
2718	case L2CAP_MODE_ERTM:
2719	case L2CAP_MODE_STREAMING:
2720		/* Check outgoing MTU */
2721		if (len > chan->omtu) {
2722			err = -EMSGSIZE;
2723			break;
2724		}
2725
2726		__skb_queue_head_init(&seg_queue);
2727
2728		/* Do segmentation before calling in to the state machine,
2729		 * since it's possible to block while waiting for memory
2730		 * allocation.
2731		 */
2732		err = l2cap_segment_sdu(chan, &seg_queue, msg, len);
2733
2734		/* The channel could have been closed while segmenting,
2735		 * check that it is still connected.
2736		 */
2737		if (chan->state != BT_CONNECTED) {
2738			__skb_queue_purge(&seg_queue);
2739			err = -ENOTCONN;
2740		}
2741
2742		if (err)
2743			break;
2744
2745		if (chan->mode == L2CAP_MODE_ERTM)
2746			l2cap_tx(chan, NULL, &seg_queue, L2CAP_EV_DATA_REQUEST);
2747		else
2748			l2cap_streaming_send(chan, &seg_queue);
2749
2750		err = len;
2751
2752		/* If the skbs were not queued for sending, they'll still be in
2753		 * seg_queue and need to be purged.
2754		 */
2755		__skb_queue_purge(&seg_queue);
2756		break;
2757
2758	default:
2759		BT_DBG("bad state %1.1x", chan->mode);
2760		err = -EBADFD;
2761	}
2762
2763	return err;
2764}
2765EXPORT_SYMBOL_GPL(l2cap_chan_send);
2766
2767static void l2cap_send_srej(struct l2cap_chan *chan, u16 txseq)
2768{
2769	struct l2cap_ctrl control;
2770	u16 seq;
2771
2772	BT_DBG("chan %p, txseq %u", chan, txseq);
2773
2774	memset(&control, 0, sizeof(control));
2775	control.sframe = 1;
2776	control.super = L2CAP_SUPER_SREJ;
2777
2778	for (seq = chan->expected_tx_seq; seq != txseq;
2779	     seq = __next_seq(chan, seq)) {
2780		if (!l2cap_ertm_seq_in_queue(&chan->srej_q, seq)) {
2781			control.reqseq = seq;
2782			l2cap_send_sframe(chan, &control);
2783			l2cap_seq_list_append(&chan->srej_list, seq);
2784		}
2785	}
2786
2787	chan->expected_tx_seq = __next_seq(chan, txseq);
2788}
2789
2790static void l2cap_send_srej_tail(struct l2cap_chan *chan)
2791{
2792	struct l2cap_ctrl control;
2793
2794	BT_DBG("chan %p", chan);
2795
2796	if (chan->srej_list.tail == L2CAP_SEQ_LIST_CLEAR)
2797		return;
2798
2799	memset(&control, 0, sizeof(control));
2800	control.sframe = 1;
2801	control.super = L2CAP_SUPER_SREJ;
2802	control.reqseq = chan->srej_list.tail;
2803	l2cap_send_sframe(chan, &control);
2804}
2805
2806static void l2cap_send_srej_list(struct l2cap_chan *chan, u16 txseq)
2807{
2808	struct l2cap_ctrl control;
2809	u16 initial_head;
2810	u16 seq;
2811
2812	BT_DBG("chan %p, txseq %u", chan, txseq);
2813
2814	memset(&control, 0, sizeof(control));
2815	control.sframe = 1;
2816	control.super = L2CAP_SUPER_SREJ;
2817
2818	/* Capture initial list head to allow only one pass through the list. */
2819	initial_head = chan->srej_list.head;
2820
2821	do {
2822		seq = l2cap_seq_list_pop(&chan->srej_list);
2823		if (seq == txseq || seq == L2CAP_SEQ_LIST_CLEAR)
2824			break;
2825
2826		control.reqseq = seq;
2827		l2cap_send_sframe(chan, &control);
2828		l2cap_seq_list_append(&chan->srej_list, seq);
2829	} while (chan->srej_list.head != initial_head);
2830}
2831
2832static void l2cap_process_reqseq(struct l2cap_chan *chan, u16 reqseq)
2833{
2834	struct sk_buff *acked_skb;
2835	u16 ackseq;
2836
2837	BT_DBG("chan %p, reqseq %u", chan, reqseq);
2838
2839	if (chan->unacked_frames == 0 || reqseq == chan->expected_ack_seq)
2840		return;
2841
2842	BT_DBG("expected_ack_seq %u, unacked_frames %u",
2843	       chan->expected_ack_seq, chan->unacked_frames);
2844
2845	for (ackseq = chan->expected_ack_seq; ackseq != reqseq;
2846	     ackseq = __next_seq(chan, ackseq)) {
2847
2848		acked_skb = l2cap_ertm_seq_in_queue(&chan->tx_q, ackseq);
2849		if (acked_skb) {
2850			skb_unlink(acked_skb, &chan->tx_q);
2851			kfree_skb(acked_skb);
2852			chan->unacked_frames--;
2853		}
2854	}
2855
2856	chan->expected_ack_seq = reqseq;
2857
2858	if (chan->unacked_frames == 0)
2859		__clear_retrans_timer(chan);
2860
2861	BT_DBG("unacked_frames %u", chan->unacked_frames);
2862}
2863
2864static void l2cap_abort_rx_srej_sent(struct l2cap_chan *chan)
2865{
2866	BT_DBG("chan %p", chan);
2867
2868	chan->expected_tx_seq = chan->buffer_seq;
2869	l2cap_seq_list_clear(&chan->srej_list);
2870	skb_queue_purge(&chan->srej_q);
2871	chan->rx_state = L2CAP_RX_STATE_RECV;
2872}
2873
2874static void l2cap_tx_state_xmit(struct l2cap_chan *chan,
2875				struct l2cap_ctrl *control,
2876				struct sk_buff_head *skbs, u8 event)
2877{
2878	BT_DBG("chan %p, control %p, skbs %p, event %d", chan, control, skbs,
2879	       event);
2880
2881	switch (event) {
2882	case L2CAP_EV_DATA_REQUEST:
2883		if (chan->tx_send_head == NULL)
2884			chan->tx_send_head = skb_peek(skbs);
2885
2886		skb_queue_splice_tail_init(skbs, &chan->tx_q);
2887		l2cap_ertm_send(chan);
2888		break;
2889	case L2CAP_EV_LOCAL_BUSY_DETECTED:
2890		BT_DBG("Enter LOCAL_BUSY");
2891		set_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2892
2893		if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) {
2894			/* The SREJ_SENT state must be aborted if we are to
2895			 * enter the LOCAL_BUSY state.
2896			 */
2897			l2cap_abort_rx_srej_sent(chan);
2898		}
2899
2900		l2cap_send_ack(chan);
2901
2902		break;
2903	case L2CAP_EV_LOCAL_BUSY_CLEAR:
2904		BT_DBG("Exit LOCAL_BUSY");
2905		clear_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2906
2907		if (test_bit(CONN_RNR_SENT, &chan->conn_state)) {
2908			struct l2cap_ctrl local_control;
2909
2910			memset(&local_control, 0, sizeof(local_control));
2911			local_control.sframe = 1;
2912			local_control.super = L2CAP_SUPER_RR;
2913			local_control.poll = 1;
2914			local_control.reqseq = chan->buffer_seq;
2915			l2cap_send_sframe(chan, &local_control);
2916
2917			chan->retry_count = 1;
2918			__set_monitor_timer(chan);
2919			chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2920		}
2921		break;
2922	case L2CAP_EV_RECV_REQSEQ_AND_FBIT:
2923		l2cap_process_reqseq(chan, control->reqseq);
2924		break;
2925	case L2CAP_EV_EXPLICIT_POLL:
2926		l2cap_send_rr_or_rnr(chan, 1);
2927		chan->retry_count = 1;
2928		__set_monitor_timer(chan);
2929		__clear_ack_timer(chan);
2930		chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2931		break;
2932	case L2CAP_EV_RETRANS_TO:
2933		l2cap_send_rr_or_rnr(chan, 1);
2934		chan->retry_count = 1;
2935		__set_monitor_timer(chan);
2936		chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2937		break;
2938	case L2CAP_EV_RECV_FBIT:
2939		/* Nothing to process */
2940		break;
2941	default:
2942		break;
2943	}
2944}
2945
2946static void l2cap_tx_state_wait_f(struct l2cap_chan *chan,
2947				  struct l2cap_ctrl *control,
2948				  struct sk_buff_head *skbs, u8 event)
2949{
2950	BT_DBG("chan %p, control %p, skbs %p, event %d", chan, control, skbs,
2951	       event);
2952
2953	switch (event) {
2954	case L2CAP_EV_DATA_REQUEST:
2955		if (chan->tx_send_head == NULL)
2956			chan->tx_send_head = skb_peek(skbs);
2957		/* Queue data, but don't send. */
2958		skb_queue_splice_tail_init(skbs, &chan->tx_q);
2959		break;
2960	case L2CAP_EV_LOCAL_BUSY_DETECTED:
2961		BT_DBG("Enter LOCAL_BUSY");
2962		set_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2963
2964		if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) {
2965			/* The SREJ_SENT state must be aborted if we are to
2966			 * enter the LOCAL_BUSY state.
2967			 */
2968			l2cap_abort_rx_srej_sent(chan);
2969		}
2970
2971		l2cap_send_ack(chan);
2972
2973		break;
2974	case L2CAP_EV_LOCAL_BUSY_CLEAR:
2975		BT_DBG("Exit LOCAL_BUSY");
2976		clear_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2977
2978		if (test_bit(CONN_RNR_SENT, &chan->conn_state)) {
2979			struct l2cap_ctrl local_control;
2980			memset(&local_control, 0, sizeof(local_control));
2981			local_control.sframe = 1;
2982			local_control.super = L2CAP_SUPER_RR;
2983			local_control.poll = 1;
2984			local_control.reqseq = chan->buffer_seq;
2985			l2cap_send_sframe(chan, &local_control);
2986
2987			chan->retry_count = 1;
2988			__set_monitor_timer(chan);
2989			chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2990		}
2991		break;
2992	case L2CAP_EV_RECV_REQSEQ_AND_FBIT:
2993		l2cap_process_reqseq(chan, control->reqseq);
2994		fallthrough;
 
2995
2996	case L2CAP_EV_RECV_FBIT:
2997		if (control && control->final) {
2998			__clear_monitor_timer(chan);
2999			if (chan->unacked_frames > 0)
3000				__set_retrans_timer(chan);
3001			chan->retry_count = 0;
3002			chan->tx_state = L2CAP_TX_STATE_XMIT;
3003			BT_DBG("recv fbit tx_state 0x2.2%x", chan->tx_state);
3004		}
3005		break;
3006	case L2CAP_EV_EXPLICIT_POLL:
3007		/* Ignore */
3008		break;
3009	case L2CAP_EV_MONITOR_TO:
3010		if (chan->max_tx == 0 || chan->retry_count < chan->max_tx) {
3011			l2cap_send_rr_or_rnr(chan, 1);
3012			__set_monitor_timer(chan);
3013			chan->retry_count++;
3014		} else {
3015			l2cap_send_disconn_req(chan, ECONNABORTED);
3016		}
3017		break;
3018	default:
3019		break;
3020	}
3021}
3022
3023static void l2cap_tx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
3024		     struct sk_buff_head *skbs, u8 event)
3025{
3026	BT_DBG("chan %p, control %p, skbs %p, event %d, state %d",
3027	       chan, control, skbs, event, chan->tx_state);
3028
3029	switch (chan->tx_state) {
3030	case L2CAP_TX_STATE_XMIT:
3031		l2cap_tx_state_xmit(chan, control, skbs, event);
3032		break;
3033	case L2CAP_TX_STATE_WAIT_F:
3034		l2cap_tx_state_wait_f(chan, control, skbs, event);
3035		break;
3036	default:
3037		/* Ignore event */
3038		break;
3039	}
3040}
3041
3042static void l2cap_pass_to_tx(struct l2cap_chan *chan,
3043			     struct l2cap_ctrl *control)
3044{
3045	BT_DBG("chan %p, control %p", chan, control);
3046	l2cap_tx(chan, control, NULL, L2CAP_EV_RECV_REQSEQ_AND_FBIT);
3047}
3048
3049static void l2cap_pass_to_tx_fbit(struct l2cap_chan *chan,
3050				  struct l2cap_ctrl *control)
3051{
3052	BT_DBG("chan %p, control %p", chan, control);
3053	l2cap_tx(chan, control, NULL, L2CAP_EV_RECV_FBIT);
3054}
3055
3056/* Copy frame to all raw sockets on that connection */
3057static void l2cap_raw_recv(struct l2cap_conn *conn, struct sk_buff *skb)
3058{
3059	struct sk_buff *nskb;
3060	struct l2cap_chan *chan;
3061
3062	BT_DBG("conn %p", conn);
3063
3064	mutex_lock(&conn->chan_lock);
3065
3066	list_for_each_entry(chan, &conn->chan_l, list) {
3067		if (chan->chan_type != L2CAP_CHAN_RAW)
3068			continue;
3069
3070		/* Don't send frame to the channel it came from */
3071		if (bt_cb(skb)->l2cap.chan == chan)
3072			continue;
3073
3074		nskb = skb_clone(skb, GFP_KERNEL);
3075		if (!nskb)
3076			continue;
3077		if (chan->ops->recv(chan, nskb))
3078			kfree_skb(nskb);
3079	}
3080
3081	mutex_unlock(&conn->chan_lock);
3082}
3083
3084/* ---- L2CAP signalling commands ---- */
3085static struct sk_buff *l2cap_build_cmd(struct l2cap_conn *conn, u8 code,
3086				       u8 ident, u16 dlen, void *data)
3087{
3088	struct sk_buff *skb, **frag;
3089	struct l2cap_cmd_hdr *cmd;
3090	struct l2cap_hdr *lh;
3091	int len, count;
3092
3093	BT_DBG("conn %p, code 0x%2.2x, ident 0x%2.2x, len %u",
3094	       conn, code, ident, dlen);
3095
3096	if (conn->mtu < L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE)
3097		return NULL;
3098
3099	len = L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE + dlen;
3100	count = min_t(unsigned int, conn->mtu, len);
3101
3102	skb = bt_skb_alloc(count, GFP_KERNEL);
3103	if (!skb)
3104		return NULL;
3105
3106	lh = skb_put(skb, L2CAP_HDR_SIZE);
3107	lh->len = cpu_to_le16(L2CAP_CMD_HDR_SIZE + dlen);
3108
3109	if (conn->hcon->type == LE_LINK)
3110		lh->cid = cpu_to_le16(L2CAP_CID_LE_SIGNALING);
3111	else
3112		lh->cid = cpu_to_le16(L2CAP_CID_SIGNALING);
3113
3114	cmd = skb_put(skb, L2CAP_CMD_HDR_SIZE);
3115	cmd->code  = code;
3116	cmd->ident = ident;
3117	cmd->len   = cpu_to_le16(dlen);
3118
3119	if (dlen) {
3120		count -= L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE;
3121		skb_put_data(skb, data, count);
3122		data += count;
3123	}
3124
3125	len -= skb->len;
3126
3127	/* Continuation fragments (no L2CAP header) */
3128	frag = &skb_shinfo(skb)->frag_list;
3129	while (len) {
3130		count = min_t(unsigned int, conn->mtu, len);
3131
3132		*frag = bt_skb_alloc(count, GFP_KERNEL);
3133		if (!*frag)
3134			goto fail;
3135
3136		skb_put_data(*frag, data, count);
3137
3138		len  -= count;
3139		data += count;
3140
3141		frag = &(*frag)->next;
3142	}
3143
3144	return skb;
3145
3146fail:
3147	kfree_skb(skb);
3148	return NULL;
3149}
3150
3151static inline int l2cap_get_conf_opt(void **ptr, int *type, int *olen,
3152				     unsigned long *val)
3153{
3154	struct l2cap_conf_opt *opt = *ptr;
3155	int len;
3156
3157	len = L2CAP_CONF_OPT_SIZE + opt->len;
3158	*ptr += len;
3159
3160	*type = opt->type;
3161	*olen = opt->len;
3162
3163	switch (opt->len) {
3164	case 1:
3165		*val = *((u8 *) opt->val);
3166		break;
3167
3168	case 2:
3169		*val = get_unaligned_le16(opt->val);
3170		break;
3171
3172	case 4:
3173		*val = get_unaligned_le32(opt->val);
3174		break;
3175
3176	default:
3177		*val = (unsigned long) opt->val;
3178		break;
3179	}
3180
3181	BT_DBG("type 0x%2.2x len %u val 0x%lx", *type, opt->len, *val);
3182	return len;
3183}
3184
3185static void l2cap_add_conf_opt(void **ptr, u8 type, u8 len, unsigned long val, size_t size)
3186{
3187	struct l2cap_conf_opt *opt = *ptr;
3188
3189	BT_DBG("type 0x%2.2x len %u val 0x%lx", type, len, val);
3190
3191	if (size < L2CAP_CONF_OPT_SIZE + len)
3192		return;
3193
3194	opt->type = type;
3195	opt->len  = len;
3196
3197	switch (len) {
3198	case 1:
3199		*((u8 *) opt->val)  = val;
3200		break;
3201
3202	case 2:
3203		put_unaligned_le16(val, opt->val);
3204		break;
3205
3206	case 4:
3207		put_unaligned_le32(val, opt->val);
3208		break;
3209
3210	default:
3211		memcpy(opt->val, (void *) val, len);
3212		break;
3213	}
3214
3215	*ptr += L2CAP_CONF_OPT_SIZE + len;
3216}
3217
3218static void l2cap_add_opt_efs(void **ptr, struct l2cap_chan *chan, size_t size)
3219{
3220	struct l2cap_conf_efs efs;
3221
3222	switch (chan->mode) {
3223	case L2CAP_MODE_ERTM:
3224		efs.id		= chan->local_id;
3225		efs.stype	= chan->local_stype;
3226		efs.msdu	= cpu_to_le16(chan->local_msdu);
3227		efs.sdu_itime	= cpu_to_le32(chan->local_sdu_itime);
3228		efs.acc_lat	= cpu_to_le32(L2CAP_DEFAULT_ACC_LAT);
3229		efs.flush_to	= cpu_to_le32(L2CAP_EFS_DEFAULT_FLUSH_TO);
3230		break;
3231
3232	case L2CAP_MODE_STREAMING:
3233		efs.id		= 1;
3234		efs.stype	= L2CAP_SERV_BESTEFFORT;
3235		efs.msdu	= cpu_to_le16(chan->local_msdu);
3236		efs.sdu_itime	= cpu_to_le32(chan->local_sdu_itime);
3237		efs.acc_lat	= 0;
3238		efs.flush_to	= 0;
3239		break;
3240
3241	default:
3242		return;
3243	}
3244
3245	l2cap_add_conf_opt(ptr, L2CAP_CONF_EFS, sizeof(efs),
3246			   (unsigned long) &efs, size);
3247}
3248
3249static void l2cap_ack_timeout(struct work_struct *work)
3250{
3251	struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
3252					       ack_timer.work);
3253	u16 frames_to_ack;
3254
3255	BT_DBG("chan %p", chan);
3256
3257	l2cap_chan_lock(chan);
3258
3259	frames_to_ack = __seq_offset(chan, chan->buffer_seq,
3260				     chan->last_acked_seq);
3261
3262	if (frames_to_ack)
3263		l2cap_send_rr_or_rnr(chan, 0);
3264
3265	l2cap_chan_unlock(chan);
3266	l2cap_chan_put(chan);
3267}
3268
3269int l2cap_ertm_init(struct l2cap_chan *chan)
3270{
3271	int err;
3272
3273	chan->next_tx_seq = 0;
3274	chan->expected_tx_seq = 0;
3275	chan->expected_ack_seq = 0;
3276	chan->unacked_frames = 0;
3277	chan->buffer_seq = 0;
3278	chan->frames_sent = 0;
3279	chan->last_acked_seq = 0;
3280	chan->sdu = NULL;
3281	chan->sdu_last_frag = NULL;
3282	chan->sdu_len = 0;
3283
3284	skb_queue_head_init(&chan->tx_q);
3285
3286	chan->local_amp_id = AMP_ID_BREDR;
3287	chan->move_id = AMP_ID_BREDR;
3288	chan->move_state = L2CAP_MOVE_STABLE;
3289	chan->move_role = L2CAP_MOVE_ROLE_NONE;
3290
3291	if (chan->mode != L2CAP_MODE_ERTM)
3292		return 0;
3293
3294	chan->rx_state = L2CAP_RX_STATE_RECV;
3295	chan->tx_state = L2CAP_TX_STATE_XMIT;
3296
3297	INIT_DELAYED_WORK(&chan->retrans_timer, l2cap_retrans_timeout);
3298	INIT_DELAYED_WORK(&chan->monitor_timer, l2cap_monitor_timeout);
3299	INIT_DELAYED_WORK(&chan->ack_timer, l2cap_ack_timeout);
3300
3301	skb_queue_head_init(&chan->srej_q);
3302
3303	err = l2cap_seq_list_init(&chan->srej_list, chan->tx_win);
3304	if (err < 0)
3305		return err;
3306
3307	err = l2cap_seq_list_init(&chan->retrans_list, chan->remote_tx_win);
3308	if (err < 0)
3309		l2cap_seq_list_free(&chan->srej_list);
3310
3311	return err;
3312}
3313
3314static inline __u8 l2cap_select_mode(__u8 mode, __u16 remote_feat_mask)
3315{
3316	switch (mode) {
3317	case L2CAP_MODE_STREAMING:
3318	case L2CAP_MODE_ERTM:
3319		if (l2cap_mode_supported(mode, remote_feat_mask))
3320			return mode;
3321		fallthrough;
3322	default:
3323		return L2CAP_MODE_BASIC;
3324	}
3325}
3326
3327static inline bool __l2cap_ews_supported(struct l2cap_conn *conn)
3328{
3329	return ((conn->local_fixed_chan & L2CAP_FC_A2MP) &&
3330		(conn->feat_mask & L2CAP_FEAT_EXT_WINDOW));
3331}
3332
3333static inline bool __l2cap_efs_supported(struct l2cap_conn *conn)
3334{
3335	return ((conn->local_fixed_chan & L2CAP_FC_A2MP) &&
3336		(conn->feat_mask & L2CAP_FEAT_EXT_FLOW));
3337}
3338
3339static void __l2cap_set_ertm_timeouts(struct l2cap_chan *chan,
3340				      struct l2cap_conf_rfc *rfc)
3341{
3342	if (chan->local_amp_id != AMP_ID_BREDR && chan->hs_hcon) {
3343		u64 ertm_to = chan->hs_hcon->hdev->amp_be_flush_to;
3344
3345		/* Class 1 devices have must have ERTM timeouts
3346		 * exceeding the Link Supervision Timeout.  The
3347		 * default Link Supervision Timeout for AMP
3348		 * controllers is 10 seconds.
3349		 *
3350		 * Class 1 devices use 0xffffffff for their
3351		 * best-effort flush timeout, so the clamping logic
3352		 * will result in a timeout that meets the above
3353		 * requirement.  ERTM timeouts are 16-bit values, so
3354		 * the maximum timeout is 65.535 seconds.
3355		 */
3356
3357		/* Convert timeout to milliseconds and round */
3358		ertm_to = DIV_ROUND_UP_ULL(ertm_to, 1000);
3359
3360		/* This is the recommended formula for class 2 devices
3361		 * that start ERTM timers when packets are sent to the
3362		 * controller.
3363		 */
3364		ertm_to = 3 * ertm_to + 500;
3365
3366		if (ertm_to > 0xffff)
3367			ertm_to = 0xffff;
3368
3369		rfc->retrans_timeout = cpu_to_le16((u16) ertm_to);
3370		rfc->monitor_timeout = rfc->retrans_timeout;
3371	} else {
3372		rfc->retrans_timeout = cpu_to_le16(L2CAP_DEFAULT_RETRANS_TO);
3373		rfc->monitor_timeout = cpu_to_le16(L2CAP_DEFAULT_MONITOR_TO);
3374	}
3375}
3376
3377static inline void l2cap_txwin_setup(struct l2cap_chan *chan)
3378{
3379	if (chan->tx_win > L2CAP_DEFAULT_TX_WINDOW &&
3380	    __l2cap_ews_supported(chan->conn)) {
3381		/* use extended control field */
3382		set_bit(FLAG_EXT_CTRL, &chan->flags);
3383		chan->tx_win_max = L2CAP_DEFAULT_EXT_WINDOW;
3384	} else {
3385		chan->tx_win = min_t(u16, chan->tx_win,
3386				     L2CAP_DEFAULT_TX_WINDOW);
3387		chan->tx_win_max = L2CAP_DEFAULT_TX_WINDOW;
3388	}
3389	chan->ack_win = chan->tx_win;
3390}
3391
3392static void l2cap_mtu_auto(struct l2cap_chan *chan)
3393{
3394	struct hci_conn *conn = chan->conn->hcon;
3395
3396	chan->imtu = L2CAP_DEFAULT_MIN_MTU;
3397
3398	/* The 2-DH1 packet has between 2 and 56 information bytes
3399	 * (including the 2-byte payload header)
3400	 */
3401	if (!(conn->pkt_type & HCI_2DH1))
3402		chan->imtu = 54;
3403
3404	/* The 3-DH1 packet has between 2 and 85 information bytes
3405	 * (including the 2-byte payload header)
3406	 */
3407	if (!(conn->pkt_type & HCI_3DH1))
3408		chan->imtu = 83;
3409
3410	/* The 2-DH3 packet has between 2 and 369 information bytes
3411	 * (including the 2-byte payload header)
3412	 */
3413	if (!(conn->pkt_type & HCI_2DH3))
3414		chan->imtu = 367;
3415
3416	/* The 3-DH3 packet has between 2 and 554 information bytes
3417	 * (including the 2-byte payload header)
3418	 */
3419	if (!(conn->pkt_type & HCI_3DH3))
3420		chan->imtu = 552;
3421
3422	/* The 2-DH5 packet has between 2 and 681 information bytes
3423	 * (including the 2-byte payload header)
3424	 */
3425	if (!(conn->pkt_type & HCI_2DH5))
3426		chan->imtu = 679;
3427
3428	/* The 3-DH5 packet has between 2 and 1023 information bytes
3429	 * (including the 2-byte payload header)
3430	 */
3431	if (!(conn->pkt_type & HCI_3DH5))
3432		chan->imtu = 1021;
3433}
3434
3435static int l2cap_build_conf_req(struct l2cap_chan *chan, void *data, size_t data_size)
3436{
3437	struct l2cap_conf_req *req = data;
3438	struct l2cap_conf_rfc rfc = { .mode = chan->mode };
3439	void *ptr = req->data;
3440	void *endptr = data + data_size;
3441	u16 size;
3442
3443	BT_DBG("chan %p", chan);
3444
3445	if (chan->num_conf_req || chan->num_conf_rsp)
3446		goto done;
3447
3448	switch (chan->mode) {
3449	case L2CAP_MODE_STREAMING:
3450	case L2CAP_MODE_ERTM:
3451		if (test_bit(CONF_STATE2_DEVICE, &chan->conf_state))
3452			break;
3453
3454		if (__l2cap_efs_supported(chan->conn))
3455			set_bit(FLAG_EFS_ENABLE, &chan->flags);
3456
3457		fallthrough;
3458	default:
3459		chan->mode = l2cap_select_mode(rfc.mode, chan->conn->feat_mask);
3460		break;
3461	}
3462
3463done:
3464	if (chan->imtu != L2CAP_DEFAULT_MTU) {
3465		if (!chan->imtu)
3466			l2cap_mtu_auto(chan);
3467		l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->imtu,
3468				   endptr - ptr);
3469	}
3470
3471	switch (chan->mode) {
3472	case L2CAP_MODE_BASIC:
3473		if (disable_ertm)
3474			break;
3475
3476		if (!(chan->conn->feat_mask & L2CAP_FEAT_ERTM) &&
3477		    !(chan->conn->feat_mask & L2CAP_FEAT_STREAMING))
3478			break;
3479
3480		rfc.mode            = L2CAP_MODE_BASIC;
3481		rfc.txwin_size      = 0;
3482		rfc.max_transmit    = 0;
3483		rfc.retrans_timeout = 0;
3484		rfc.monitor_timeout = 0;
3485		rfc.max_pdu_size    = 0;
3486
3487		l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3488				   (unsigned long) &rfc, endptr - ptr);
3489		break;
3490
3491	case L2CAP_MODE_ERTM:
3492		rfc.mode            = L2CAP_MODE_ERTM;
3493		rfc.max_transmit    = chan->max_tx;
3494
3495		__l2cap_set_ertm_timeouts(chan, &rfc);
3496
3497		size = min_t(u16, L2CAP_DEFAULT_MAX_PDU_SIZE, chan->conn->mtu -
3498			     L2CAP_EXT_HDR_SIZE - L2CAP_SDULEN_SIZE -
3499			     L2CAP_FCS_SIZE);
3500		rfc.max_pdu_size = cpu_to_le16(size);
3501
3502		l2cap_txwin_setup(chan);
3503
3504		rfc.txwin_size = min_t(u16, chan->tx_win,
3505				       L2CAP_DEFAULT_TX_WINDOW);
3506
3507		l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3508				   (unsigned long) &rfc, endptr - ptr);
3509
3510		if (test_bit(FLAG_EFS_ENABLE, &chan->flags))
3511			l2cap_add_opt_efs(&ptr, chan, endptr - ptr);
3512
3513		if (test_bit(FLAG_EXT_CTRL, &chan->flags))
3514			l2cap_add_conf_opt(&ptr, L2CAP_CONF_EWS, 2,
3515					   chan->tx_win, endptr - ptr);
3516
3517		if (chan->conn->feat_mask & L2CAP_FEAT_FCS)
3518			if (chan->fcs == L2CAP_FCS_NONE ||
3519			    test_bit(CONF_RECV_NO_FCS, &chan->conf_state)) {
3520				chan->fcs = L2CAP_FCS_NONE;
3521				l2cap_add_conf_opt(&ptr, L2CAP_CONF_FCS, 1,
3522						   chan->fcs, endptr - ptr);
3523			}
3524		break;
3525
3526	case L2CAP_MODE_STREAMING:
3527		l2cap_txwin_setup(chan);
3528		rfc.mode            = L2CAP_MODE_STREAMING;
3529		rfc.txwin_size      = 0;
3530		rfc.max_transmit    = 0;
3531		rfc.retrans_timeout = 0;
3532		rfc.monitor_timeout = 0;
3533
3534		size = min_t(u16, L2CAP_DEFAULT_MAX_PDU_SIZE, chan->conn->mtu -
3535			     L2CAP_EXT_HDR_SIZE - L2CAP_SDULEN_SIZE -
3536			     L2CAP_FCS_SIZE);
3537		rfc.max_pdu_size = cpu_to_le16(size);
3538
3539		l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3540				   (unsigned long) &rfc, endptr - ptr);
3541
3542		if (test_bit(FLAG_EFS_ENABLE, &chan->flags))
3543			l2cap_add_opt_efs(&ptr, chan, endptr - ptr);
3544
3545		if (chan->conn->feat_mask & L2CAP_FEAT_FCS)
3546			if (chan->fcs == L2CAP_FCS_NONE ||
3547			    test_bit(CONF_RECV_NO_FCS, &chan->conf_state)) {
3548				chan->fcs = L2CAP_FCS_NONE;
3549				l2cap_add_conf_opt(&ptr, L2CAP_CONF_FCS, 1,
3550						   chan->fcs, endptr - ptr);
3551			}
3552		break;
3553	}
3554
3555	req->dcid  = cpu_to_le16(chan->dcid);
3556	req->flags = cpu_to_le16(0);
3557
3558	return ptr - data;
3559}
3560
3561static int l2cap_parse_conf_req(struct l2cap_chan *chan, void *data, size_t data_size)
3562{
3563	struct l2cap_conf_rsp *rsp = data;
3564	void *ptr = rsp->data;
3565	void *endptr = data + data_size;
3566	void *req = chan->conf_req;
3567	int len = chan->conf_len;
3568	int type, hint, olen;
3569	unsigned long val;
3570	struct l2cap_conf_rfc rfc = { .mode = L2CAP_MODE_BASIC };
3571	struct l2cap_conf_efs efs;
3572	u8 remote_efs = 0;
3573	u16 mtu = L2CAP_DEFAULT_MTU;
3574	u16 result = L2CAP_CONF_SUCCESS;
3575	u16 size;
3576
3577	BT_DBG("chan %p", chan);
3578
3579	while (len >= L2CAP_CONF_OPT_SIZE) {
3580		len -= l2cap_get_conf_opt(&req, &type, &olen, &val);
3581		if (len < 0)
3582			break;
3583
3584		hint  = type & L2CAP_CONF_HINT;
3585		type &= L2CAP_CONF_MASK;
3586
3587		switch (type) {
3588		case L2CAP_CONF_MTU:
3589			if (olen != 2)
3590				break;
3591			mtu = val;
3592			break;
3593
3594		case L2CAP_CONF_FLUSH_TO:
3595			if (olen != 2)
3596				break;
3597			chan->flush_to = val;
3598			break;
3599
3600		case L2CAP_CONF_QOS:
3601			break;
3602
3603		case L2CAP_CONF_RFC:
3604			if (olen != sizeof(rfc))
3605				break;
3606			memcpy(&rfc, (void *) val, olen);
3607			break;
3608
3609		case L2CAP_CONF_FCS:
3610			if (olen != 1)
3611				break;
3612			if (val == L2CAP_FCS_NONE)
3613				set_bit(CONF_RECV_NO_FCS, &chan->conf_state);
3614			break;
3615
3616		case L2CAP_CONF_EFS:
3617			if (olen != sizeof(efs))
3618				break;
3619			remote_efs = 1;
3620			memcpy(&efs, (void *) val, olen);
 
3621			break;
3622
3623		case L2CAP_CONF_EWS:
3624			if (olen != 2)
3625				break;
3626			if (!(chan->conn->local_fixed_chan & L2CAP_FC_A2MP))
3627				return -ECONNREFUSED;
 
3628			set_bit(FLAG_EXT_CTRL, &chan->flags);
3629			set_bit(CONF_EWS_RECV, &chan->conf_state);
3630			chan->tx_win_max = L2CAP_DEFAULT_EXT_WINDOW;
3631			chan->remote_tx_win = val;
3632			break;
3633
3634		default:
3635			if (hint)
3636				break;
 
3637			result = L2CAP_CONF_UNKNOWN;
3638			l2cap_add_conf_opt(&ptr, (u8)type, sizeof(u8), type, endptr - ptr);
3639			break;
3640		}
3641	}
3642
3643	if (chan->num_conf_rsp || chan->num_conf_req > 1)
3644		goto done;
3645
3646	switch (chan->mode) {
3647	case L2CAP_MODE_STREAMING:
3648	case L2CAP_MODE_ERTM:
3649		if (!test_bit(CONF_STATE2_DEVICE, &chan->conf_state)) {
3650			chan->mode = l2cap_select_mode(rfc.mode,
3651						       chan->conn->feat_mask);
3652			break;
3653		}
3654
3655		if (remote_efs) {
3656			if (__l2cap_efs_supported(chan->conn))
3657				set_bit(FLAG_EFS_ENABLE, &chan->flags);
3658			else
3659				return -ECONNREFUSED;
3660		}
3661
3662		if (chan->mode != rfc.mode)
3663			return -ECONNREFUSED;
3664
3665		break;
3666	}
3667
3668done:
3669	if (chan->mode != rfc.mode) {
3670		result = L2CAP_CONF_UNACCEPT;
3671		rfc.mode = chan->mode;
3672
3673		if (chan->num_conf_rsp == 1)
3674			return -ECONNREFUSED;
3675
3676		l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3677				   (unsigned long) &rfc, endptr - ptr);
3678	}
3679
3680	if (result == L2CAP_CONF_SUCCESS) {
3681		/* Configure output options and let the other side know
3682		 * which ones we don't like. */
3683
3684		if (mtu < L2CAP_DEFAULT_MIN_MTU)
3685			result = L2CAP_CONF_UNACCEPT;
3686		else {
3687			chan->omtu = mtu;
3688			set_bit(CONF_MTU_DONE, &chan->conf_state);
3689		}
3690		l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->omtu, endptr - ptr);
3691
3692		if (remote_efs) {
3693			if (chan->local_stype != L2CAP_SERV_NOTRAFIC &&
3694			    efs.stype != L2CAP_SERV_NOTRAFIC &&
3695			    efs.stype != chan->local_stype) {
3696
3697				result = L2CAP_CONF_UNACCEPT;
3698
3699				if (chan->num_conf_req >= 1)
3700					return -ECONNREFUSED;
3701
3702				l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS,
3703						   sizeof(efs),
3704						   (unsigned long) &efs, endptr - ptr);
3705			} else {
3706				/* Send PENDING Conf Rsp */
3707				result = L2CAP_CONF_PENDING;
3708				set_bit(CONF_LOC_CONF_PEND, &chan->conf_state);
3709			}
3710		}
3711
3712		switch (rfc.mode) {
3713		case L2CAP_MODE_BASIC:
3714			chan->fcs = L2CAP_FCS_NONE;
3715			set_bit(CONF_MODE_DONE, &chan->conf_state);
3716			break;
3717
3718		case L2CAP_MODE_ERTM:
3719			if (!test_bit(CONF_EWS_RECV, &chan->conf_state))
3720				chan->remote_tx_win = rfc.txwin_size;
3721			else
3722				rfc.txwin_size = L2CAP_DEFAULT_TX_WINDOW;
3723
3724			chan->remote_max_tx = rfc.max_transmit;
3725
3726			size = min_t(u16, le16_to_cpu(rfc.max_pdu_size),
3727				     chan->conn->mtu - L2CAP_EXT_HDR_SIZE -
3728				     L2CAP_SDULEN_SIZE - L2CAP_FCS_SIZE);
3729			rfc.max_pdu_size = cpu_to_le16(size);
3730			chan->remote_mps = size;
3731
3732			__l2cap_set_ertm_timeouts(chan, &rfc);
3733
3734			set_bit(CONF_MODE_DONE, &chan->conf_state);
3735
3736			l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC,
3737					   sizeof(rfc), (unsigned long) &rfc, endptr - ptr);
3738
3739			if (test_bit(FLAG_EFS_ENABLE, &chan->flags)) {
3740				chan->remote_id = efs.id;
3741				chan->remote_stype = efs.stype;
3742				chan->remote_msdu = le16_to_cpu(efs.msdu);
3743				chan->remote_flush_to =
3744					le32_to_cpu(efs.flush_to);
3745				chan->remote_acc_lat =
3746					le32_to_cpu(efs.acc_lat);
3747				chan->remote_sdu_itime =
3748					le32_to_cpu(efs.sdu_itime);
3749				l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS,
3750						   sizeof(efs),
3751						   (unsigned long) &efs, endptr - ptr);
3752			}
3753			break;
3754
3755		case L2CAP_MODE_STREAMING:
3756			size = min_t(u16, le16_to_cpu(rfc.max_pdu_size),
3757				     chan->conn->mtu - L2CAP_EXT_HDR_SIZE -
3758				     L2CAP_SDULEN_SIZE - L2CAP_FCS_SIZE);
3759			rfc.max_pdu_size = cpu_to_le16(size);
3760			chan->remote_mps = size;
3761
3762			set_bit(CONF_MODE_DONE, &chan->conf_state);
3763
3764			l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3765					   (unsigned long) &rfc, endptr - ptr);
3766
3767			break;
3768
3769		default:
3770			result = L2CAP_CONF_UNACCEPT;
3771
3772			memset(&rfc, 0, sizeof(rfc));
3773			rfc.mode = chan->mode;
3774		}
3775
3776		if (result == L2CAP_CONF_SUCCESS)
3777			set_bit(CONF_OUTPUT_DONE, &chan->conf_state);
3778	}
3779	rsp->scid   = cpu_to_le16(chan->dcid);
3780	rsp->result = cpu_to_le16(result);
3781	rsp->flags  = cpu_to_le16(0);
3782
3783	return ptr - data;
3784}
3785
3786static int l2cap_parse_conf_rsp(struct l2cap_chan *chan, void *rsp, int len,
3787				void *data, size_t size, u16 *result)
3788{
3789	struct l2cap_conf_req *req = data;
3790	void *ptr = req->data;
3791	void *endptr = data + size;
3792	int type, olen;
3793	unsigned long val;
3794	struct l2cap_conf_rfc rfc = { .mode = L2CAP_MODE_BASIC };
3795	struct l2cap_conf_efs efs;
3796
3797	BT_DBG("chan %p, rsp %p, len %d, req %p", chan, rsp, len, data);
3798
3799	while (len >= L2CAP_CONF_OPT_SIZE) {
3800		len -= l2cap_get_conf_opt(&rsp, &type, &olen, &val);
3801		if (len < 0)
3802			break;
3803
3804		switch (type) {
3805		case L2CAP_CONF_MTU:
3806			if (olen != 2)
3807				break;
3808			if (val < L2CAP_DEFAULT_MIN_MTU) {
3809				*result = L2CAP_CONF_UNACCEPT;
3810				chan->imtu = L2CAP_DEFAULT_MIN_MTU;
3811			} else
3812				chan->imtu = val;
3813			l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->imtu,
3814					   endptr - ptr);
3815			break;
3816
3817		case L2CAP_CONF_FLUSH_TO:
3818			if (olen != 2)
3819				break;
3820			chan->flush_to = val;
3821			l2cap_add_conf_opt(&ptr, L2CAP_CONF_FLUSH_TO, 2,
3822					   chan->flush_to, endptr - ptr);
3823			break;
3824
3825		case L2CAP_CONF_RFC:
3826			if (olen != sizeof(rfc))
3827				break;
3828			memcpy(&rfc, (void *)val, olen);
3829			if (test_bit(CONF_STATE2_DEVICE, &chan->conf_state) &&
3830			    rfc.mode != chan->mode)
3831				return -ECONNREFUSED;
 
3832			chan->fcs = 0;
3833			l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3834					   (unsigned long) &rfc, endptr - ptr);
 
3835			break;
3836
3837		case L2CAP_CONF_EWS:
3838			if (olen != 2)
3839				break;
3840			chan->ack_win = min_t(u16, val, chan->ack_win);
3841			l2cap_add_conf_opt(&ptr, L2CAP_CONF_EWS, 2,
3842					   chan->tx_win, endptr - ptr);
3843			break;
3844
3845		case L2CAP_CONF_EFS:
3846			if (olen != sizeof(efs))
3847				break;
3848			memcpy(&efs, (void *)val, olen);
3849			if (chan->local_stype != L2CAP_SERV_NOTRAFIC &&
3850			    efs.stype != L2CAP_SERV_NOTRAFIC &&
3851			    efs.stype != chan->local_stype)
3852				return -ECONNREFUSED;
 
3853			l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS, sizeof(efs),
3854					   (unsigned long) &efs, endptr - ptr);
3855			break;
3856
3857		case L2CAP_CONF_FCS:
3858			if (olen != 1)
3859				break;
3860			if (*result == L2CAP_CONF_PENDING)
3861				if (val == L2CAP_FCS_NONE)
3862					set_bit(CONF_RECV_NO_FCS,
3863						&chan->conf_state);
3864			break;
3865		}
3866	}
3867
3868	if (chan->mode == L2CAP_MODE_BASIC && chan->mode != rfc.mode)
3869		return -ECONNREFUSED;
3870
3871	chan->mode = rfc.mode;
3872
3873	if (*result == L2CAP_CONF_SUCCESS || *result == L2CAP_CONF_PENDING) {
3874		switch (rfc.mode) {
3875		case L2CAP_MODE_ERTM:
3876			chan->retrans_timeout = le16_to_cpu(rfc.retrans_timeout);
3877			chan->monitor_timeout = le16_to_cpu(rfc.monitor_timeout);
3878			chan->mps    = le16_to_cpu(rfc.max_pdu_size);
3879			if (!test_bit(FLAG_EXT_CTRL, &chan->flags))
3880				chan->ack_win = min_t(u16, chan->ack_win,
3881						      rfc.txwin_size);
3882
3883			if (test_bit(FLAG_EFS_ENABLE, &chan->flags)) {
3884				chan->local_msdu = le16_to_cpu(efs.msdu);
3885				chan->local_sdu_itime =
3886					le32_to_cpu(efs.sdu_itime);
3887				chan->local_acc_lat = le32_to_cpu(efs.acc_lat);
3888				chan->local_flush_to =
3889					le32_to_cpu(efs.flush_to);
3890			}
3891			break;
3892
3893		case L2CAP_MODE_STREAMING:
3894			chan->mps    = le16_to_cpu(rfc.max_pdu_size);
3895		}
3896	}
3897
3898	req->dcid   = cpu_to_le16(chan->dcid);
3899	req->flags  = cpu_to_le16(0);
3900
3901	return ptr - data;
3902}
3903
3904static int l2cap_build_conf_rsp(struct l2cap_chan *chan, void *data,
3905				u16 result, u16 flags)
3906{
3907	struct l2cap_conf_rsp *rsp = data;
3908	void *ptr = rsp->data;
3909
3910	BT_DBG("chan %p", chan);
3911
3912	rsp->scid   = cpu_to_le16(chan->dcid);
3913	rsp->result = cpu_to_le16(result);
3914	rsp->flags  = cpu_to_le16(flags);
3915
3916	return ptr - data;
3917}
3918
3919void __l2cap_le_connect_rsp_defer(struct l2cap_chan *chan)
3920{
3921	struct l2cap_le_conn_rsp rsp;
3922	struct l2cap_conn *conn = chan->conn;
3923
3924	BT_DBG("chan %p", chan);
3925
3926	rsp.dcid    = cpu_to_le16(chan->scid);
3927	rsp.mtu     = cpu_to_le16(chan->imtu);
3928	rsp.mps     = cpu_to_le16(chan->mps);
3929	rsp.credits = cpu_to_le16(chan->rx_credits);
3930	rsp.result  = cpu_to_le16(L2CAP_CR_LE_SUCCESS);
3931
3932	l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CONN_RSP, sizeof(rsp),
3933		       &rsp);
3934}
3935
3936void __l2cap_ecred_conn_rsp_defer(struct l2cap_chan *chan)
3937{
3938	struct {
3939		struct l2cap_ecred_conn_rsp rsp;
3940		__le16 dcid[5];
3941	} __packed pdu;
3942	struct l2cap_conn *conn = chan->conn;
3943	u16 ident = chan->ident;
3944	int i = 0;
3945
3946	if (!ident)
3947		return;
3948
3949	BT_DBG("chan %p ident %d", chan, ident);
3950
3951	pdu.rsp.mtu     = cpu_to_le16(chan->imtu);
3952	pdu.rsp.mps     = cpu_to_le16(chan->mps);
3953	pdu.rsp.credits = cpu_to_le16(chan->rx_credits);
3954	pdu.rsp.result  = cpu_to_le16(L2CAP_CR_LE_SUCCESS);
3955
3956	mutex_lock(&conn->chan_lock);
3957
3958	list_for_each_entry(chan, &conn->chan_l, list) {
3959		if (chan->ident != ident)
3960			continue;
3961
3962		/* Reset ident so only one response is sent */
3963		chan->ident = 0;
3964
3965		/* Include all channels pending with the same ident */
3966		pdu.dcid[i++] = cpu_to_le16(chan->scid);
3967	}
3968
3969	mutex_unlock(&conn->chan_lock);
3970
3971	l2cap_send_cmd(conn, ident, L2CAP_ECRED_CONN_RSP,
3972			sizeof(pdu.rsp) + i * sizeof(__le16), &pdu);
3973}
3974
3975void __l2cap_connect_rsp_defer(struct l2cap_chan *chan)
3976{
3977	struct l2cap_conn_rsp rsp;
3978	struct l2cap_conn *conn = chan->conn;
3979	u8 buf[128];
3980	u8 rsp_code;
3981
3982	rsp.scid   = cpu_to_le16(chan->dcid);
3983	rsp.dcid   = cpu_to_le16(chan->scid);
3984	rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
3985	rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
3986
3987	if (chan->hs_hcon)
3988		rsp_code = L2CAP_CREATE_CHAN_RSP;
3989	else
3990		rsp_code = L2CAP_CONN_RSP;
3991
3992	BT_DBG("chan %p rsp_code %u", chan, rsp_code);
3993
3994	l2cap_send_cmd(conn, chan->ident, rsp_code, sizeof(rsp), &rsp);
3995
3996	if (test_and_set_bit(CONF_REQ_SENT, &chan->conf_state))
3997		return;
3998
3999	l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
4000		       l2cap_build_conf_req(chan, buf, sizeof(buf)), buf);
4001	chan->num_conf_req++;
4002}
4003
4004static void l2cap_conf_rfc_get(struct l2cap_chan *chan, void *rsp, int len)
4005{
4006	int type, olen;
4007	unsigned long val;
4008	/* Use sane default values in case a misbehaving remote device
4009	 * did not send an RFC or extended window size option.
4010	 */
4011	u16 txwin_ext = chan->ack_win;
4012	struct l2cap_conf_rfc rfc = {
4013		.mode = chan->mode,
4014		.retrans_timeout = cpu_to_le16(L2CAP_DEFAULT_RETRANS_TO),
4015		.monitor_timeout = cpu_to_le16(L2CAP_DEFAULT_MONITOR_TO),
4016		.max_pdu_size = cpu_to_le16(chan->imtu),
4017		.txwin_size = min_t(u16, chan->ack_win, L2CAP_DEFAULT_TX_WINDOW),
4018	};
4019
4020	BT_DBG("chan %p, rsp %p, len %d", chan, rsp, len);
4021
4022	if ((chan->mode != L2CAP_MODE_ERTM) && (chan->mode != L2CAP_MODE_STREAMING))
4023		return;
4024
4025	while (len >= L2CAP_CONF_OPT_SIZE) {
4026		len -= l2cap_get_conf_opt(&rsp, &type, &olen, &val);
4027		if (len < 0)
4028			break;
4029
4030		switch (type) {
4031		case L2CAP_CONF_RFC:
4032			if (olen != sizeof(rfc))
4033				break;
4034			memcpy(&rfc, (void *)val, olen);
4035			break;
4036		case L2CAP_CONF_EWS:
4037			if (olen != 2)
4038				break;
4039			txwin_ext = val;
4040			break;
4041		}
4042	}
4043
4044	switch (rfc.mode) {
4045	case L2CAP_MODE_ERTM:
4046		chan->retrans_timeout = le16_to_cpu(rfc.retrans_timeout);
4047		chan->monitor_timeout = le16_to_cpu(rfc.monitor_timeout);
4048		chan->mps = le16_to_cpu(rfc.max_pdu_size);
4049		if (test_bit(FLAG_EXT_CTRL, &chan->flags))
4050			chan->ack_win = min_t(u16, chan->ack_win, txwin_ext);
4051		else
4052			chan->ack_win = min_t(u16, chan->ack_win,
4053					      rfc.txwin_size);
4054		break;
4055	case L2CAP_MODE_STREAMING:
4056		chan->mps    = le16_to_cpu(rfc.max_pdu_size);
4057	}
4058}
4059
4060static inline int l2cap_command_rej(struct l2cap_conn *conn,
4061				    struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4062				    u8 *data)
4063{
4064	struct l2cap_cmd_rej_unk *rej = (struct l2cap_cmd_rej_unk *) data;
4065
4066	if (cmd_len < sizeof(*rej))
4067		return -EPROTO;
4068
4069	if (rej->reason != L2CAP_REJ_NOT_UNDERSTOOD)
4070		return 0;
4071
4072	if ((conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT) &&
4073	    cmd->ident == conn->info_ident) {
4074		cancel_delayed_work(&conn->info_timer);
4075
4076		conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4077		conn->info_ident = 0;
4078
4079		l2cap_conn_start(conn);
4080	}
4081
4082	return 0;
4083}
4084
4085static struct l2cap_chan *l2cap_connect(struct l2cap_conn *conn,
4086					struct l2cap_cmd_hdr *cmd,
4087					u8 *data, u8 rsp_code, u8 amp_id)
4088{
4089	struct l2cap_conn_req *req = (struct l2cap_conn_req *) data;
4090	struct l2cap_conn_rsp rsp;
4091	struct l2cap_chan *chan = NULL, *pchan;
4092	int result, status = L2CAP_CS_NO_INFO;
4093
4094	u16 dcid = 0, scid = __le16_to_cpu(req->scid);
4095	__le16 psm = req->psm;
4096
4097	BT_DBG("psm 0x%2.2x scid 0x%4.4x", __le16_to_cpu(psm), scid);
4098
4099	/* Check if we have socket listening on psm */
4100	pchan = l2cap_global_chan_by_psm(BT_LISTEN, psm, &conn->hcon->src,
4101					 &conn->hcon->dst, ACL_LINK);
4102	if (!pchan) {
4103		result = L2CAP_CR_BAD_PSM;
4104		goto sendresp;
4105	}
4106
4107	mutex_lock(&conn->chan_lock);
4108	l2cap_chan_lock(pchan);
4109
4110	/* Check if the ACL is secure enough (if not SDP) */
4111	if (psm != cpu_to_le16(L2CAP_PSM_SDP) &&
4112	    !hci_conn_check_link_mode(conn->hcon)) {
4113		conn->disc_reason = HCI_ERROR_AUTH_FAILURE;
4114		result = L2CAP_CR_SEC_BLOCK;
4115		goto response;
4116	}
4117
4118	result = L2CAP_CR_NO_MEM;
4119
4120	/* Check for valid dynamic CID range (as per Erratum 3253) */
4121	if (scid < L2CAP_CID_DYN_START || scid > L2CAP_CID_DYN_END) {
4122		result = L2CAP_CR_INVALID_SCID;
4123		goto response;
4124	}
4125
4126	/* Check if we already have channel with that dcid */
4127	if (__l2cap_get_chan_by_dcid(conn, scid)) {
4128		result = L2CAP_CR_SCID_IN_USE;
4129		goto response;
4130	}
4131
4132	chan = pchan->ops->new_connection(pchan);
4133	if (!chan)
4134		goto response;
4135
4136	/* For certain devices (ex: HID mouse), support for authentication,
4137	 * pairing and bonding is optional. For such devices, inorder to avoid
4138	 * the ACL alive for too long after L2CAP disconnection, reset the ACL
4139	 * disc_timeout back to HCI_DISCONN_TIMEOUT during L2CAP connect.
4140	 */
4141	conn->hcon->disc_timeout = HCI_DISCONN_TIMEOUT;
4142
4143	bacpy(&chan->src, &conn->hcon->src);
4144	bacpy(&chan->dst, &conn->hcon->dst);
4145	chan->src_type = bdaddr_src_type(conn->hcon);
4146	chan->dst_type = bdaddr_dst_type(conn->hcon);
4147	chan->psm  = psm;
4148	chan->dcid = scid;
4149	chan->local_amp_id = amp_id;
4150
4151	__l2cap_chan_add(conn, chan);
4152
4153	dcid = chan->scid;
4154
4155	__set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
4156
4157	chan->ident = cmd->ident;
4158
4159	if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE) {
4160		if (l2cap_chan_check_security(chan, false)) {
4161			if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
4162				l2cap_state_change(chan, BT_CONNECT2);
4163				result = L2CAP_CR_PEND;
4164				status = L2CAP_CS_AUTHOR_PEND;
4165				chan->ops->defer(chan);
4166			} else {
4167				/* Force pending result for AMP controllers.
4168				 * The connection will succeed after the
4169				 * physical link is up.
4170				 */
4171				if (amp_id == AMP_ID_BREDR) {
4172					l2cap_state_change(chan, BT_CONFIG);
4173					result = L2CAP_CR_SUCCESS;
4174				} else {
4175					l2cap_state_change(chan, BT_CONNECT2);
4176					result = L2CAP_CR_PEND;
4177				}
4178				status = L2CAP_CS_NO_INFO;
4179			}
4180		} else {
4181			l2cap_state_change(chan, BT_CONNECT2);
4182			result = L2CAP_CR_PEND;
4183			status = L2CAP_CS_AUTHEN_PEND;
4184		}
4185	} else {
4186		l2cap_state_change(chan, BT_CONNECT2);
4187		result = L2CAP_CR_PEND;
4188		status = L2CAP_CS_NO_INFO;
4189	}
4190
4191response:
4192	l2cap_chan_unlock(pchan);
4193	mutex_unlock(&conn->chan_lock);
4194	l2cap_chan_put(pchan);
4195
4196sendresp:
4197	rsp.scid   = cpu_to_le16(scid);
4198	rsp.dcid   = cpu_to_le16(dcid);
4199	rsp.result = cpu_to_le16(result);
4200	rsp.status = cpu_to_le16(status);
4201	l2cap_send_cmd(conn, cmd->ident, rsp_code, sizeof(rsp), &rsp);
4202
4203	if (result == L2CAP_CR_PEND && status == L2CAP_CS_NO_INFO) {
4204		struct l2cap_info_req info;
4205		info.type = cpu_to_le16(L2CAP_IT_FEAT_MASK);
4206
4207		conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_SENT;
4208		conn->info_ident = l2cap_get_ident(conn);
4209
4210		schedule_delayed_work(&conn->info_timer, L2CAP_INFO_TIMEOUT);
4211
4212		l2cap_send_cmd(conn, conn->info_ident, L2CAP_INFO_REQ,
4213			       sizeof(info), &info);
4214	}
4215
4216	if (chan && !test_bit(CONF_REQ_SENT, &chan->conf_state) &&
4217	    result == L2CAP_CR_SUCCESS) {
4218		u8 buf[128];
4219		set_bit(CONF_REQ_SENT, &chan->conf_state);
4220		l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
4221			       l2cap_build_conf_req(chan, buf, sizeof(buf)), buf);
4222		chan->num_conf_req++;
4223	}
4224
4225	return chan;
4226}
4227
4228static int l2cap_connect_req(struct l2cap_conn *conn,
4229			     struct l2cap_cmd_hdr *cmd, u16 cmd_len, u8 *data)
4230{
4231	struct hci_dev *hdev = conn->hcon->hdev;
4232	struct hci_conn *hcon = conn->hcon;
4233
4234	if (cmd_len < sizeof(struct l2cap_conn_req))
4235		return -EPROTO;
4236
4237	hci_dev_lock(hdev);
4238	if (hci_dev_test_flag(hdev, HCI_MGMT) &&
4239	    !test_and_set_bit(HCI_CONN_MGMT_CONNECTED, &hcon->flags))
4240		mgmt_device_connected(hdev, hcon, NULL, 0);
4241	hci_dev_unlock(hdev);
4242
4243	l2cap_connect(conn, cmd, data, L2CAP_CONN_RSP, 0);
4244	return 0;
4245}
4246
4247static int l2cap_connect_create_rsp(struct l2cap_conn *conn,
4248				    struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4249				    u8 *data)
4250{
4251	struct l2cap_conn_rsp *rsp = (struct l2cap_conn_rsp *) data;
4252	u16 scid, dcid, result, status;
4253	struct l2cap_chan *chan;
4254	u8 req[128];
4255	int err;
4256
4257	if (cmd_len < sizeof(*rsp))
4258		return -EPROTO;
4259
4260	scid   = __le16_to_cpu(rsp->scid);
4261	dcid   = __le16_to_cpu(rsp->dcid);
4262	result = __le16_to_cpu(rsp->result);
4263	status = __le16_to_cpu(rsp->status);
4264
4265	BT_DBG("dcid 0x%4.4x scid 0x%4.4x result 0x%2.2x status 0x%2.2x",
4266	       dcid, scid, result, status);
4267
4268	mutex_lock(&conn->chan_lock);
4269
4270	if (scid) {
4271		chan = __l2cap_get_chan_by_scid(conn, scid);
4272		if (!chan) {
4273			err = -EBADSLT;
4274			goto unlock;
4275		}
4276	} else {
4277		chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
4278		if (!chan) {
4279			err = -EBADSLT;
4280			goto unlock;
4281		}
4282	}
4283
4284	err = 0;
4285
4286	l2cap_chan_lock(chan);
4287
4288	switch (result) {
4289	case L2CAP_CR_SUCCESS:
4290		l2cap_state_change(chan, BT_CONFIG);
4291		chan->ident = 0;
4292		chan->dcid = dcid;
4293		clear_bit(CONF_CONNECT_PEND, &chan->conf_state);
4294
4295		if (test_and_set_bit(CONF_REQ_SENT, &chan->conf_state))
4296			break;
4297
4298		l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
4299			       l2cap_build_conf_req(chan, req, sizeof(req)), req);
4300		chan->num_conf_req++;
4301		break;
4302
4303	case L2CAP_CR_PEND:
4304		set_bit(CONF_CONNECT_PEND, &chan->conf_state);
4305		break;
4306
4307	default:
4308		l2cap_chan_del(chan, ECONNREFUSED);
4309		break;
4310	}
4311
4312	l2cap_chan_unlock(chan);
4313
4314unlock:
4315	mutex_unlock(&conn->chan_lock);
4316
4317	return err;
4318}
4319
4320static inline void set_default_fcs(struct l2cap_chan *chan)
4321{
4322	/* FCS is enabled only in ERTM or streaming mode, if one or both
4323	 * sides request it.
4324	 */
4325	if (chan->mode != L2CAP_MODE_ERTM && chan->mode != L2CAP_MODE_STREAMING)
4326		chan->fcs = L2CAP_FCS_NONE;
4327	else if (!test_bit(CONF_RECV_NO_FCS, &chan->conf_state))
4328		chan->fcs = L2CAP_FCS_CRC16;
4329}
4330
4331static void l2cap_send_efs_conf_rsp(struct l2cap_chan *chan, void *data,
4332				    u8 ident, u16 flags)
4333{
4334	struct l2cap_conn *conn = chan->conn;
4335
4336	BT_DBG("conn %p chan %p ident %d flags 0x%4.4x", conn, chan, ident,
4337	       flags);
4338
4339	clear_bit(CONF_LOC_CONF_PEND, &chan->conf_state);
4340	set_bit(CONF_OUTPUT_DONE, &chan->conf_state);
4341
4342	l2cap_send_cmd(conn, ident, L2CAP_CONF_RSP,
4343		       l2cap_build_conf_rsp(chan, data,
4344					    L2CAP_CONF_SUCCESS, flags), data);
4345}
4346
4347static void cmd_reject_invalid_cid(struct l2cap_conn *conn, u8 ident,
4348				   u16 scid, u16 dcid)
4349{
4350	struct l2cap_cmd_rej_cid rej;
4351
4352	rej.reason = cpu_to_le16(L2CAP_REJ_INVALID_CID);
4353	rej.scid = __cpu_to_le16(scid);
4354	rej.dcid = __cpu_to_le16(dcid);
4355
4356	l2cap_send_cmd(conn, ident, L2CAP_COMMAND_REJ, sizeof(rej), &rej);
4357}
4358
4359static inline int l2cap_config_req(struct l2cap_conn *conn,
4360				   struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4361				   u8 *data)
4362{
4363	struct l2cap_conf_req *req = (struct l2cap_conf_req *) data;
4364	u16 dcid, flags;
4365	u8 rsp[64];
4366	struct l2cap_chan *chan;
4367	int len, err = 0;
4368
4369	if (cmd_len < sizeof(*req))
4370		return -EPROTO;
4371
4372	dcid  = __le16_to_cpu(req->dcid);
4373	flags = __le16_to_cpu(req->flags);
4374
4375	BT_DBG("dcid 0x%4.4x flags 0x%2.2x", dcid, flags);
4376
4377	chan = l2cap_get_chan_by_scid(conn, dcid);
4378	if (!chan) {
4379		cmd_reject_invalid_cid(conn, cmd->ident, dcid, 0);
4380		return 0;
4381	}
4382
4383	if (chan->state != BT_CONFIG && chan->state != BT_CONNECT2 &&
4384	    chan->state != BT_CONNECTED) {
4385		cmd_reject_invalid_cid(conn, cmd->ident, chan->scid,
4386				       chan->dcid);
4387		goto unlock;
4388	}
4389
4390	/* Reject if config buffer is too small. */
4391	len = cmd_len - sizeof(*req);
4392	if (chan->conf_len + len > sizeof(chan->conf_req)) {
4393		l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP,
4394			       l2cap_build_conf_rsp(chan, rsp,
4395			       L2CAP_CONF_REJECT, flags), rsp);
4396		goto unlock;
4397	}
4398
4399	/* Store config. */
4400	memcpy(chan->conf_req + chan->conf_len, req->data, len);
4401	chan->conf_len += len;
4402
4403	if (flags & L2CAP_CONF_FLAG_CONTINUATION) {
4404		/* Incomplete config. Send empty response. */
4405		l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP,
4406			       l2cap_build_conf_rsp(chan, rsp,
4407			       L2CAP_CONF_SUCCESS, flags), rsp);
4408		goto unlock;
4409	}
4410
4411	/* Complete config. */
4412	len = l2cap_parse_conf_req(chan, rsp, sizeof(rsp));
4413	if (len < 0) {
4414		l2cap_send_disconn_req(chan, ECONNRESET);
4415		goto unlock;
4416	}
4417
4418	chan->ident = cmd->ident;
4419	l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP, len, rsp);
4420	chan->num_conf_rsp++;
4421
4422	/* Reset config buffer. */
4423	chan->conf_len = 0;
4424
4425	if (!test_bit(CONF_OUTPUT_DONE, &chan->conf_state))
4426		goto unlock;
4427
4428	if (test_bit(CONF_INPUT_DONE, &chan->conf_state)) {
4429		set_default_fcs(chan);
4430
4431		if (chan->mode == L2CAP_MODE_ERTM ||
4432		    chan->mode == L2CAP_MODE_STREAMING)
4433			err = l2cap_ertm_init(chan);
4434
4435		if (err < 0)
4436			l2cap_send_disconn_req(chan, -err);
4437		else
4438			l2cap_chan_ready(chan);
4439
4440		goto unlock;
4441	}
4442
4443	if (!test_and_set_bit(CONF_REQ_SENT, &chan->conf_state)) {
4444		u8 buf[64];
4445		l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
4446			       l2cap_build_conf_req(chan, buf, sizeof(buf)), buf);
4447		chan->num_conf_req++;
4448	}
4449
4450	/* Got Conf Rsp PENDING from remote side and assume we sent
4451	   Conf Rsp PENDING in the code above */
4452	if (test_bit(CONF_REM_CONF_PEND, &chan->conf_state) &&
4453	    test_bit(CONF_LOC_CONF_PEND, &chan->conf_state)) {
4454
4455		/* check compatibility */
4456
4457		/* Send rsp for BR/EDR channel */
4458		if (!chan->hs_hcon)
4459			l2cap_send_efs_conf_rsp(chan, rsp, cmd->ident, flags);
4460		else
4461			chan->ident = cmd->ident;
4462	}
4463
4464unlock:
4465	l2cap_chan_unlock(chan);
4466	return err;
4467}
4468
4469static inline int l2cap_config_rsp(struct l2cap_conn *conn,
4470				   struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4471				   u8 *data)
4472{
4473	struct l2cap_conf_rsp *rsp = (struct l2cap_conf_rsp *)data;
4474	u16 scid, flags, result;
4475	struct l2cap_chan *chan;
4476	int len = cmd_len - sizeof(*rsp);
4477	int err = 0;
4478
4479	if (cmd_len < sizeof(*rsp))
4480		return -EPROTO;
4481
4482	scid   = __le16_to_cpu(rsp->scid);
4483	flags  = __le16_to_cpu(rsp->flags);
4484	result = __le16_to_cpu(rsp->result);
4485
4486	BT_DBG("scid 0x%4.4x flags 0x%2.2x result 0x%2.2x len %d", scid, flags,
4487	       result, len);
4488
4489	chan = l2cap_get_chan_by_scid(conn, scid);
4490	if (!chan)
4491		return 0;
4492
4493	switch (result) {
4494	case L2CAP_CONF_SUCCESS:
4495		l2cap_conf_rfc_get(chan, rsp->data, len);
4496		clear_bit(CONF_REM_CONF_PEND, &chan->conf_state);
4497		break;
4498
4499	case L2CAP_CONF_PENDING:
4500		set_bit(CONF_REM_CONF_PEND, &chan->conf_state);
4501
4502		if (test_bit(CONF_LOC_CONF_PEND, &chan->conf_state)) {
4503			char buf[64];
4504
4505			len = l2cap_parse_conf_rsp(chan, rsp->data, len,
4506						   buf, sizeof(buf), &result);
4507			if (len < 0) {
4508				l2cap_send_disconn_req(chan, ECONNRESET);
4509				goto done;
4510			}
4511
4512			if (!chan->hs_hcon) {
4513				l2cap_send_efs_conf_rsp(chan, buf, cmd->ident,
4514							0);
4515			} else {
4516				if (l2cap_check_efs(chan)) {
4517					amp_create_logical_link(chan);
4518					chan->ident = cmd->ident;
4519				}
4520			}
4521		}
4522		goto done;
4523
4524	case L2CAP_CONF_UNKNOWN:
4525	case L2CAP_CONF_UNACCEPT:
4526		if (chan->num_conf_rsp <= L2CAP_CONF_MAX_CONF_RSP) {
4527			char req[64];
4528
4529			if (len > sizeof(req) - sizeof(struct l2cap_conf_req)) {
4530				l2cap_send_disconn_req(chan, ECONNRESET);
4531				goto done;
4532			}
4533
4534			/* throw out any old stored conf requests */
4535			result = L2CAP_CONF_SUCCESS;
4536			len = l2cap_parse_conf_rsp(chan, rsp->data, len,
4537						   req, sizeof(req), &result);
4538			if (len < 0) {
4539				l2cap_send_disconn_req(chan, ECONNRESET);
4540				goto done;
4541			}
4542
4543			l2cap_send_cmd(conn, l2cap_get_ident(conn),
4544				       L2CAP_CONF_REQ, len, req);
4545			chan->num_conf_req++;
4546			if (result != L2CAP_CONF_SUCCESS)
4547				goto done;
4548			break;
4549		}
4550		fallthrough;
4551
4552	default:
4553		l2cap_chan_set_err(chan, ECONNRESET);
4554
4555		__set_chan_timer(chan, L2CAP_DISC_REJ_TIMEOUT);
4556		l2cap_send_disconn_req(chan, ECONNRESET);
4557		goto done;
4558	}
4559
4560	if (flags & L2CAP_CONF_FLAG_CONTINUATION)
4561		goto done;
4562
4563	set_bit(CONF_INPUT_DONE, &chan->conf_state);
4564
4565	if (test_bit(CONF_OUTPUT_DONE, &chan->conf_state)) {
4566		set_default_fcs(chan);
4567
4568		if (chan->mode == L2CAP_MODE_ERTM ||
4569		    chan->mode == L2CAP_MODE_STREAMING)
4570			err = l2cap_ertm_init(chan);
4571
4572		if (err < 0)
4573			l2cap_send_disconn_req(chan, -err);
4574		else
4575			l2cap_chan_ready(chan);
4576	}
4577
4578done:
4579	l2cap_chan_unlock(chan);
4580	return err;
4581}
4582
4583static inline int l2cap_disconnect_req(struct l2cap_conn *conn,
4584				       struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4585				       u8 *data)
4586{
4587	struct l2cap_disconn_req *req = (struct l2cap_disconn_req *) data;
4588	struct l2cap_disconn_rsp rsp;
4589	u16 dcid, scid;
4590	struct l2cap_chan *chan;
4591
4592	if (cmd_len != sizeof(*req))
4593		return -EPROTO;
4594
4595	scid = __le16_to_cpu(req->scid);
4596	dcid = __le16_to_cpu(req->dcid);
4597
4598	BT_DBG("scid 0x%4.4x dcid 0x%4.4x", scid, dcid);
4599
4600	mutex_lock(&conn->chan_lock);
4601
4602	chan = __l2cap_get_chan_by_scid(conn, dcid);
4603	if (!chan) {
4604		mutex_unlock(&conn->chan_lock);
4605		cmd_reject_invalid_cid(conn, cmd->ident, dcid, scid);
4606		return 0;
4607	}
4608
4609	l2cap_chan_hold(chan);
4610	l2cap_chan_lock(chan);
4611
4612	rsp.dcid = cpu_to_le16(chan->scid);
4613	rsp.scid = cpu_to_le16(chan->dcid);
4614	l2cap_send_cmd(conn, cmd->ident, L2CAP_DISCONN_RSP, sizeof(rsp), &rsp);
4615
4616	chan->ops->set_shutdown(chan);
4617
 
4618	l2cap_chan_del(chan, ECONNRESET);
4619
 
 
4620	chan->ops->close(chan);
4621
4622	l2cap_chan_unlock(chan);
4623	l2cap_chan_put(chan);
4624
4625	mutex_unlock(&conn->chan_lock);
4626
4627	return 0;
4628}
4629
4630static inline int l2cap_disconnect_rsp(struct l2cap_conn *conn,
4631				       struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4632				       u8 *data)
4633{
4634	struct l2cap_disconn_rsp *rsp = (struct l2cap_disconn_rsp *) data;
4635	u16 dcid, scid;
4636	struct l2cap_chan *chan;
4637
4638	if (cmd_len != sizeof(*rsp))
4639		return -EPROTO;
4640
4641	scid = __le16_to_cpu(rsp->scid);
4642	dcid = __le16_to_cpu(rsp->dcid);
4643
4644	BT_DBG("dcid 0x%4.4x scid 0x%4.4x", dcid, scid);
4645
4646	mutex_lock(&conn->chan_lock);
4647
4648	chan = __l2cap_get_chan_by_scid(conn, scid);
4649	if (!chan) {
4650		mutex_unlock(&conn->chan_lock);
4651		return 0;
4652	}
4653
4654	l2cap_chan_hold(chan);
4655	l2cap_chan_lock(chan);
4656
4657	if (chan->state != BT_DISCONN) {
4658		l2cap_chan_unlock(chan);
4659		l2cap_chan_put(chan);
4660		mutex_unlock(&conn->chan_lock);
4661		return 0;
4662	}
4663
4664	l2cap_chan_del(chan, 0);
4665
4666	chan->ops->close(chan);
4667
4668	l2cap_chan_unlock(chan);
4669	l2cap_chan_put(chan);
4670
4671	mutex_unlock(&conn->chan_lock);
4672
4673	return 0;
4674}
4675
4676static inline int l2cap_information_req(struct l2cap_conn *conn,
4677					struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4678					u8 *data)
4679{
4680	struct l2cap_info_req *req = (struct l2cap_info_req *) data;
4681	u16 type;
4682
4683	if (cmd_len != sizeof(*req))
4684		return -EPROTO;
4685
4686	type = __le16_to_cpu(req->type);
4687
4688	BT_DBG("type 0x%4.4x", type);
4689
4690	if (type == L2CAP_IT_FEAT_MASK) {
4691		u8 buf[8];
4692		u32 feat_mask = l2cap_feat_mask;
4693		struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) buf;
4694		rsp->type   = cpu_to_le16(L2CAP_IT_FEAT_MASK);
4695		rsp->result = cpu_to_le16(L2CAP_IR_SUCCESS);
4696		if (!disable_ertm)
4697			feat_mask |= L2CAP_FEAT_ERTM | L2CAP_FEAT_STREAMING
4698				| L2CAP_FEAT_FCS;
4699		if (conn->local_fixed_chan & L2CAP_FC_A2MP)
4700			feat_mask |= L2CAP_FEAT_EXT_FLOW
4701				| L2CAP_FEAT_EXT_WINDOW;
4702
4703		put_unaligned_le32(feat_mask, rsp->data);
4704		l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(buf),
4705			       buf);
4706	} else if (type == L2CAP_IT_FIXED_CHAN) {
4707		u8 buf[12];
4708		struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) buf;
4709
4710		rsp->type   = cpu_to_le16(L2CAP_IT_FIXED_CHAN);
4711		rsp->result = cpu_to_le16(L2CAP_IR_SUCCESS);
4712		rsp->data[0] = conn->local_fixed_chan;
4713		memset(rsp->data + 1, 0, 7);
4714		l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(buf),
4715			       buf);
4716	} else {
4717		struct l2cap_info_rsp rsp;
4718		rsp.type   = cpu_to_le16(type);
4719		rsp.result = cpu_to_le16(L2CAP_IR_NOTSUPP);
4720		l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(rsp),
4721			       &rsp);
4722	}
4723
4724	return 0;
4725}
4726
4727static inline int l2cap_information_rsp(struct l2cap_conn *conn,
4728					struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4729					u8 *data)
4730{
4731	struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) data;
4732	u16 type, result;
4733
4734	if (cmd_len < sizeof(*rsp))
4735		return -EPROTO;
4736
4737	type   = __le16_to_cpu(rsp->type);
4738	result = __le16_to_cpu(rsp->result);
4739
4740	BT_DBG("type 0x%4.4x result 0x%2.2x", type, result);
4741
4742	/* L2CAP Info req/rsp are unbound to channels, add extra checks */
4743	if (cmd->ident != conn->info_ident ||
4744	    conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE)
4745		return 0;
4746
4747	cancel_delayed_work(&conn->info_timer);
4748
4749	if (result != L2CAP_IR_SUCCESS) {
4750		conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4751		conn->info_ident = 0;
4752
4753		l2cap_conn_start(conn);
4754
4755		return 0;
4756	}
4757
4758	switch (type) {
4759	case L2CAP_IT_FEAT_MASK:
4760		conn->feat_mask = get_unaligned_le32(rsp->data);
4761
4762		if (conn->feat_mask & L2CAP_FEAT_FIXED_CHAN) {
4763			struct l2cap_info_req req;
4764			req.type = cpu_to_le16(L2CAP_IT_FIXED_CHAN);
4765
4766			conn->info_ident = l2cap_get_ident(conn);
4767
4768			l2cap_send_cmd(conn, conn->info_ident,
4769				       L2CAP_INFO_REQ, sizeof(req), &req);
4770		} else {
4771			conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4772			conn->info_ident = 0;
4773
4774			l2cap_conn_start(conn);
4775		}
4776		break;
4777
4778	case L2CAP_IT_FIXED_CHAN:
4779		conn->remote_fixed_chan = rsp->data[0];
4780		conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4781		conn->info_ident = 0;
4782
4783		l2cap_conn_start(conn);
4784		break;
4785	}
4786
4787	return 0;
4788}
4789
4790static int l2cap_create_channel_req(struct l2cap_conn *conn,
4791				    struct l2cap_cmd_hdr *cmd,
4792				    u16 cmd_len, void *data)
4793{
4794	struct l2cap_create_chan_req *req = data;
4795	struct l2cap_create_chan_rsp rsp;
4796	struct l2cap_chan *chan;
4797	struct hci_dev *hdev;
4798	u16 psm, scid;
4799
4800	if (cmd_len != sizeof(*req))
4801		return -EPROTO;
4802
4803	if (!(conn->local_fixed_chan & L2CAP_FC_A2MP))
4804		return -EINVAL;
4805
4806	psm = le16_to_cpu(req->psm);
4807	scid = le16_to_cpu(req->scid);
4808
4809	BT_DBG("psm 0x%2.2x, scid 0x%4.4x, amp_id %d", psm, scid, req->amp_id);
4810
4811	/* For controller id 0 make BR/EDR connection */
4812	if (req->amp_id == AMP_ID_BREDR) {
4813		l2cap_connect(conn, cmd, data, L2CAP_CREATE_CHAN_RSP,
4814			      req->amp_id);
4815		return 0;
4816	}
4817
4818	/* Validate AMP controller id */
4819	hdev = hci_dev_get(req->amp_id);
4820	if (!hdev)
4821		goto error;
4822
4823	if (hdev->dev_type != HCI_AMP || !test_bit(HCI_UP, &hdev->flags)) {
4824		hci_dev_put(hdev);
4825		goto error;
4826	}
4827
4828	chan = l2cap_connect(conn, cmd, data, L2CAP_CREATE_CHAN_RSP,
4829			     req->amp_id);
4830	if (chan) {
4831		struct amp_mgr *mgr = conn->hcon->amp_mgr;
4832		struct hci_conn *hs_hcon;
4833
4834		hs_hcon = hci_conn_hash_lookup_ba(hdev, AMP_LINK,
4835						  &conn->hcon->dst);
4836		if (!hs_hcon) {
4837			hci_dev_put(hdev);
4838			cmd_reject_invalid_cid(conn, cmd->ident, chan->scid,
4839					       chan->dcid);
4840			return 0;
4841		}
4842
4843		BT_DBG("mgr %p bredr_chan %p hs_hcon %p", mgr, chan, hs_hcon);
4844
4845		mgr->bredr_chan = chan;
4846		chan->hs_hcon = hs_hcon;
4847		chan->fcs = L2CAP_FCS_NONE;
4848		conn->mtu = hdev->block_mtu;
4849	}
4850
4851	hci_dev_put(hdev);
4852
4853	return 0;
4854
4855error:
4856	rsp.dcid = 0;
4857	rsp.scid = cpu_to_le16(scid);
4858	rsp.result = cpu_to_le16(L2CAP_CR_BAD_AMP);
4859	rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
4860
4861	l2cap_send_cmd(conn, cmd->ident, L2CAP_CREATE_CHAN_RSP,
4862		       sizeof(rsp), &rsp);
4863
4864	return 0;
4865}
4866
4867static void l2cap_send_move_chan_req(struct l2cap_chan *chan, u8 dest_amp_id)
4868{
4869	struct l2cap_move_chan_req req;
4870	u8 ident;
4871
4872	BT_DBG("chan %p, dest_amp_id %d", chan, dest_amp_id);
4873
4874	ident = l2cap_get_ident(chan->conn);
4875	chan->ident = ident;
4876
4877	req.icid = cpu_to_le16(chan->scid);
4878	req.dest_amp_id = dest_amp_id;
4879
4880	l2cap_send_cmd(chan->conn, ident, L2CAP_MOVE_CHAN_REQ, sizeof(req),
4881		       &req);
4882
4883	__set_chan_timer(chan, L2CAP_MOVE_TIMEOUT);
4884}
4885
4886static void l2cap_send_move_chan_rsp(struct l2cap_chan *chan, u16 result)
4887{
4888	struct l2cap_move_chan_rsp rsp;
4889
4890	BT_DBG("chan %p, result 0x%4.4x", chan, result);
4891
4892	rsp.icid = cpu_to_le16(chan->dcid);
4893	rsp.result = cpu_to_le16(result);
4894
4895	l2cap_send_cmd(chan->conn, chan->ident, L2CAP_MOVE_CHAN_RSP,
4896		       sizeof(rsp), &rsp);
4897}
4898
4899static void l2cap_send_move_chan_cfm(struct l2cap_chan *chan, u16 result)
4900{
4901	struct l2cap_move_chan_cfm cfm;
4902
4903	BT_DBG("chan %p, result 0x%4.4x", chan, result);
4904
4905	chan->ident = l2cap_get_ident(chan->conn);
4906
4907	cfm.icid = cpu_to_le16(chan->scid);
4908	cfm.result = cpu_to_le16(result);
4909
4910	l2cap_send_cmd(chan->conn, chan->ident, L2CAP_MOVE_CHAN_CFM,
4911		       sizeof(cfm), &cfm);
4912
4913	__set_chan_timer(chan, L2CAP_MOVE_TIMEOUT);
4914}
4915
4916static void l2cap_send_move_chan_cfm_icid(struct l2cap_conn *conn, u16 icid)
4917{
4918	struct l2cap_move_chan_cfm cfm;
4919
4920	BT_DBG("conn %p, icid 0x%4.4x", conn, icid);
4921
4922	cfm.icid = cpu_to_le16(icid);
4923	cfm.result = cpu_to_le16(L2CAP_MC_UNCONFIRMED);
4924
4925	l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_MOVE_CHAN_CFM,
4926		       sizeof(cfm), &cfm);
4927}
4928
4929static void l2cap_send_move_chan_cfm_rsp(struct l2cap_conn *conn, u8 ident,
4930					 u16 icid)
4931{
4932	struct l2cap_move_chan_cfm_rsp rsp;
4933
4934	BT_DBG("icid 0x%4.4x", icid);
4935
4936	rsp.icid = cpu_to_le16(icid);
4937	l2cap_send_cmd(conn, ident, L2CAP_MOVE_CHAN_CFM_RSP, sizeof(rsp), &rsp);
4938}
4939
4940static void __release_logical_link(struct l2cap_chan *chan)
4941{
4942	chan->hs_hchan = NULL;
4943	chan->hs_hcon = NULL;
4944
4945	/* Placeholder - release the logical link */
4946}
4947
4948static void l2cap_logical_fail(struct l2cap_chan *chan)
4949{
4950	/* Logical link setup failed */
4951	if (chan->state != BT_CONNECTED) {
4952		/* Create channel failure, disconnect */
4953		l2cap_send_disconn_req(chan, ECONNRESET);
4954		return;
4955	}
4956
4957	switch (chan->move_role) {
4958	case L2CAP_MOVE_ROLE_RESPONDER:
4959		l2cap_move_done(chan);
4960		l2cap_send_move_chan_rsp(chan, L2CAP_MR_NOT_SUPP);
4961		break;
4962	case L2CAP_MOVE_ROLE_INITIATOR:
4963		if (chan->move_state == L2CAP_MOVE_WAIT_LOGICAL_COMP ||
4964		    chan->move_state == L2CAP_MOVE_WAIT_LOGICAL_CFM) {
4965			/* Remote has only sent pending or
4966			 * success responses, clean up
4967			 */
4968			l2cap_move_done(chan);
4969		}
4970
4971		/* Other amp move states imply that the move
4972		 * has already aborted
4973		 */
4974		l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
4975		break;
4976	}
4977}
4978
4979static void l2cap_logical_finish_create(struct l2cap_chan *chan,
4980					struct hci_chan *hchan)
4981{
4982	struct l2cap_conf_rsp rsp;
4983
4984	chan->hs_hchan = hchan;
4985	chan->hs_hcon->l2cap_data = chan->conn;
4986
4987	l2cap_send_efs_conf_rsp(chan, &rsp, chan->ident, 0);
4988
4989	if (test_bit(CONF_INPUT_DONE, &chan->conf_state)) {
4990		int err;
4991
4992		set_default_fcs(chan);
4993
4994		err = l2cap_ertm_init(chan);
4995		if (err < 0)
4996			l2cap_send_disconn_req(chan, -err);
4997		else
4998			l2cap_chan_ready(chan);
4999	}
5000}
5001
5002static void l2cap_logical_finish_move(struct l2cap_chan *chan,
5003				      struct hci_chan *hchan)
5004{
5005	chan->hs_hcon = hchan->conn;
5006	chan->hs_hcon->l2cap_data = chan->conn;
5007
5008	BT_DBG("move_state %d", chan->move_state);
5009
5010	switch (chan->move_state) {
5011	case L2CAP_MOVE_WAIT_LOGICAL_COMP:
5012		/* Move confirm will be sent after a success
5013		 * response is received
5014		 */
5015		chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
5016		break;
5017	case L2CAP_MOVE_WAIT_LOGICAL_CFM:
5018		if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
5019			chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
5020		} else if (chan->move_role == L2CAP_MOVE_ROLE_INITIATOR) {
5021			chan->move_state = L2CAP_MOVE_WAIT_CONFIRM_RSP;
5022			l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
5023		} else if (chan->move_role == L2CAP_MOVE_ROLE_RESPONDER) {
5024			chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
5025			l2cap_send_move_chan_rsp(chan, L2CAP_MR_SUCCESS);
5026		}
5027		break;
5028	default:
5029		/* Move was not in expected state, free the channel */
5030		__release_logical_link(chan);
5031
5032		chan->move_state = L2CAP_MOVE_STABLE;
5033	}
5034}
5035
5036/* Call with chan locked */
5037void l2cap_logical_cfm(struct l2cap_chan *chan, struct hci_chan *hchan,
5038		       u8 status)
5039{
5040	BT_DBG("chan %p, hchan %p, status %d", chan, hchan, status);
5041
5042	if (status) {
5043		l2cap_logical_fail(chan);
5044		__release_logical_link(chan);
5045		return;
5046	}
5047
5048	if (chan->state != BT_CONNECTED) {
5049		/* Ignore logical link if channel is on BR/EDR */
5050		if (chan->local_amp_id != AMP_ID_BREDR)
5051			l2cap_logical_finish_create(chan, hchan);
5052	} else {
5053		l2cap_logical_finish_move(chan, hchan);
5054	}
5055}
5056
5057void l2cap_move_start(struct l2cap_chan *chan)
5058{
5059	BT_DBG("chan %p", chan);
5060
5061	if (chan->local_amp_id == AMP_ID_BREDR) {
5062		if (chan->chan_policy != BT_CHANNEL_POLICY_AMP_PREFERRED)
5063			return;
5064		chan->move_role = L2CAP_MOVE_ROLE_INITIATOR;
5065		chan->move_state = L2CAP_MOVE_WAIT_PREPARE;
5066		/* Placeholder - start physical link setup */
5067	} else {
5068		chan->move_role = L2CAP_MOVE_ROLE_INITIATOR;
5069		chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
5070		chan->move_id = 0;
5071		l2cap_move_setup(chan);
5072		l2cap_send_move_chan_req(chan, 0);
5073	}
5074}
5075
5076static void l2cap_do_create(struct l2cap_chan *chan, int result,
5077			    u8 local_amp_id, u8 remote_amp_id)
5078{
5079	BT_DBG("chan %p state %s %u -> %u", chan, state_to_string(chan->state),
5080	       local_amp_id, remote_amp_id);
5081
5082	chan->fcs = L2CAP_FCS_NONE;
5083
5084	/* Outgoing channel on AMP */
5085	if (chan->state == BT_CONNECT) {
5086		if (result == L2CAP_CR_SUCCESS) {
5087			chan->local_amp_id = local_amp_id;
5088			l2cap_send_create_chan_req(chan, remote_amp_id);
5089		} else {
5090			/* Revert to BR/EDR connect */
5091			l2cap_send_conn_req(chan);
5092		}
5093
5094		return;
5095	}
5096
5097	/* Incoming channel on AMP */
5098	if (__l2cap_no_conn_pending(chan)) {
5099		struct l2cap_conn_rsp rsp;
5100		char buf[128];
5101		rsp.scid = cpu_to_le16(chan->dcid);
5102		rsp.dcid = cpu_to_le16(chan->scid);
5103
5104		if (result == L2CAP_CR_SUCCESS) {
5105			/* Send successful response */
5106			rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
5107			rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
5108		} else {
5109			/* Send negative response */
5110			rsp.result = cpu_to_le16(L2CAP_CR_NO_MEM);
5111			rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
5112		}
5113
5114		l2cap_send_cmd(chan->conn, chan->ident, L2CAP_CREATE_CHAN_RSP,
5115			       sizeof(rsp), &rsp);
5116
5117		if (result == L2CAP_CR_SUCCESS) {
5118			l2cap_state_change(chan, BT_CONFIG);
5119			set_bit(CONF_REQ_SENT, &chan->conf_state);
5120			l2cap_send_cmd(chan->conn, l2cap_get_ident(chan->conn),
5121				       L2CAP_CONF_REQ,
5122				       l2cap_build_conf_req(chan, buf, sizeof(buf)), buf);
5123			chan->num_conf_req++;
5124		}
5125	}
5126}
5127
5128static void l2cap_do_move_initiate(struct l2cap_chan *chan, u8 local_amp_id,
5129				   u8 remote_amp_id)
5130{
5131	l2cap_move_setup(chan);
5132	chan->move_id = local_amp_id;
5133	chan->move_state = L2CAP_MOVE_WAIT_RSP;
5134
5135	l2cap_send_move_chan_req(chan, remote_amp_id);
5136}
5137
5138static void l2cap_do_move_respond(struct l2cap_chan *chan, int result)
5139{
5140	struct hci_chan *hchan = NULL;
5141
5142	/* Placeholder - get hci_chan for logical link */
5143
5144	if (hchan) {
5145		if (hchan->state == BT_CONNECTED) {
5146			/* Logical link is ready to go */
5147			chan->hs_hcon = hchan->conn;
5148			chan->hs_hcon->l2cap_data = chan->conn;
5149			chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
5150			l2cap_send_move_chan_rsp(chan, L2CAP_MR_SUCCESS);
5151
5152			l2cap_logical_cfm(chan, hchan, L2CAP_MR_SUCCESS);
5153		} else {
5154			/* Wait for logical link to be ready */
5155			chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
5156		}
5157	} else {
5158		/* Logical link not available */
5159		l2cap_send_move_chan_rsp(chan, L2CAP_MR_NOT_ALLOWED);
5160	}
5161}
5162
5163static void l2cap_do_move_cancel(struct l2cap_chan *chan, int result)
5164{
5165	if (chan->move_role == L2CAP_MOVE_ROLE_RESPONDER) {
5166		u8 rsp_result;
5167		if (result == -EINVAL)
5168			rsp_result = L2CAP_MR_BAD_ID;
5169		else
5170			rsp_result = L2CAP_MR_NOT_ALLOWED;
5171
5172		l2cap_send_move_chan_rsp(chan, rsp_result);
5173	}
5174
5175	chan->move_role = L2CAP_MOVE_ROLE_NONE;
5176	chan->move_state = L2CAP_MOVE_STABLE;
5177
5178	/* Restart data transmission */
5179	l2cap_ertm_send(chan);
5180}
5181
5182/* Invoke with locked chan */
5183void __l2cap_physical_cfm(struct l2cap_chan *chan, int result)
5184{
5185	u8 local_amp_id = chan->local_amp_id;
5186	u8 remote_amp_id = chan->remote_amp_id;
5187
5188	BT_DBG("chan %p, result %d, local_amp_id %d, remote_amp_id %d",
5189	       chan, result, local_amp_id, remote_amp_id);
5190
5191	if (chan->state == BT_DISCONN || chan->state == BT_CLOSED)
 
5192		return;
 
5193
5194	if (chan->state != BT_CONNECTED) {
5195		l2cap_do_create(chan, result, local_amp_id, remote_amp_id);
5196	} else if (result != L2CAP_MR_SUCCESS) {
5197		l2cap_do_move_cancel(chan, result);
5198	} else {
5199		switch (chan->move_role) {
5200		case L2CAP_MOVE_ROLE_INITIATOR:
5201			l2cap_do_move_initiate(chan, local_amp_id,
5202					       remote_amp_id);
5203			break;
5204		case L2CAP_MOVE_ROLE_RESPONDER:
5205			l2cap_do_move_respond(chan, result);
5206			break;
5207		default:
5208			l2cap_do_move_cancel(chan, result);
5209			break;
5210		}
5211	}
5212}
5213
5214static inline int l2cap_move_channel_req(struct l2cap_conn *conn,
5215					 struct l2cap_cmd_hdr *cmd,
5216					 u16 cmd_len, void *data)
5217{
5218	struct l2cap_move_chan_req *req = data;
5219	struct l2cap_move_chan_rsp rsp;
5220	struct l2cap_chan *chan;
5221	u16 icid = 0;
5222	u16 result = L2CAP_MR_NOT_ALLOWED;
5223
5224	if (cmd_len != sizeof(*req))
5225		return -EPROTO;
5226
5227	icid = le16_to_cpu(req->icid);
5228
5229	BT_DBG("icid 0x%4.4x, dest_amp_id %d", icid, req->dest_amp_id);
5230
5231	if (!(conn->local_fixed_chan & L2CAP_FC_A2MP))
5232		return -EINVAL;
5233
5234	chan = l2cap_get_chan_by_dcid(conn, icid);
5235	if (!chan) {
5236		rsp.icid = cpu_to_le16(icid);
5237		rsp.result = cpu_to_le16(L2CAP_MR_NOT_ALLOWED);
5238		l2cap_send_cmd(conn, cmd->ident, L2CAP_MOVE_CHAN_RSP,
5239			       sizeof(rsp), &rsp);
5240		return 0;
5241	}
5242
5243	chan->ident = cmd->ident;
5244
5245	if (chan->scid < L2CAP_CID_DYN_START ||
5246	    chan->chan_policy == BT_CHANNEL_POLICY_BREDR_ONLY ||
5247	    (chan->mode != L2CAP_MODE_ERTM &&
5248	     chan->mode != L2CAP_MODE_STREAMING)) {
5249		result = L2CAP_MR_NOT_ALLOWED;
5250		goto send_move_response;
5251	}
5252
5253	if (chan->local_amp_id == req->dest_amp_id) {
5254		result = L2CAP_MR_SAME_ID;
5255		goto send_move_response;
5256	}
5257
5258	if (req->dest_amp_id != AMP_ID_BREDR) {
5259		struct hci_dev *hdev;
5260		hdev = hci_dev_get(req->dest_amp_id);
5261		if (!hdev || hdev->dev_type != HCI_AMP ||
5262		    !test_bit(HCI_UP, &hdev->flags)) {
5263			if (hdev)
5264				hci_dev_put(hdev);
5265
5266			result = L2CAP_MR_BAD_ID;
5267			goto send_move_response;
5268		}
5269		hci_dev_put(hdev);
5270	}
5271
5272	/* Detect a move collision.  Only send a collision response
5273	 * if this side has "lost", otherwise proceed with the move.
5274	 * The winner has the larger bd_addr.
5275	 */
5276	if ((__chan_is_moving(chan) ||
5277	     chan->move_role != L2CAP_MOVE_ROLE_NONE) &&
5278	    bacmp(&conn->hcon->src, &conn->hcon->dst) > 0) {
5279		result = L2CAP_MR_COLLISION;
5280		goto send_move_response;
5281	}
5282
5283	chan->move_role = L2CAP_MOVE_ROLE_RESPONDER;
5284	l2cap_move_setup(chan);
5285	chan->move_id = req->dest_amp_id;
 
5286
5287	if (req->dest_amp_id == AMP_ID_BREDR) {
5288		/* Moving to BR/EDR */
5289		if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
5290			chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
5291			result = L2CAP_MR_PEND;
5292		} else {
5293			chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
5294			result = L2CAP_MR_SUCCESS;
5295		}
5296	} else {
5297		chan->move_state = L2CAP_MOVE_WAIT_PREPARE;
5298		/* Placeholder - uncomment when amp functions are available */
5299		/*amp_accept_physical(chan, req->dest_amp_id);*/
5300		result = L2CAP_MR_PEND;
5301	}
5302
5303send_move_response:
5304	l2cap_send_move_chan_rsp(chan, result);
5305
5306	l2cap_chan_unlock(chan);
5307
5308	return 0;
5309}
5310
5311static void l2cap_move_continue(struct l2cap_conn *conn, u16 icid, u16 result)
5312{
5313	struct l2cap_chan *chan;
5314	struct hci_chan *hchan = NULL;
5315
5316	chan = l2cap_get_chan_by_scid(conn, icid);
5317	if (!chan) {
5318		l2cap_send_move_chan_cfm_icid(conn, icid);
5319		return;
5320	}
5321
5322	__clear_chan_timer(chan);
5323	if (result == L2CAP_MR_PEND)
5324		__set_chan_timer(chan, L2CAP_MOVE_ERTX_TIMEOUT);
5325
5326	switch (chan->move_state) {
5327	case L2CAP_MOVE_WAIT_LOGICAL_COMP:
5328		/* Move confirm will be sent when logical link
5329		 * is complete.
5330		 */
5331		chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
5332		break;
5333	case L2CAP_MOVE_WAIT_RSP_SUCCESS:
5334		if (result == L2CAP_MR_PEND) {
5335			break;
5336		} else if (test_bit(CONN_LOCAL_BUSY,
5337				    &chan->conn_state)) {
5338			chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
5339		} else {
5340			/* Logical link is up or moving to BR/EDR,
5341			 * proceed with move
5342			 */
5343			chan->move_state = L2CAP_MOVE_WAIT_CONFIRM_RSP;
5344			l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
5345		}
5346		break;
5347	case L2CAP_MOVE_WAIT_RSP:
5348		/* Moving to AMP */
5349		if (result == L2CAP_MR_SUCCESS) {
5350			/* Remote is ready, send confirm immediately
5351			 * after logical link is ready
5352			 */
5353			chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
5354		} else {
5355			/* Both logical link and move success
5356			 * are required to confirm
5357			 */
5358			chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_COMP;
5359		}
5360
5361		/* Placeholder - get hci_chan for logical link */
5362		if (!hchan) {
5363			/* Logical link not available */
5364			l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5365			break;
5366		}
5367
5368		/* If the logical link is not yet connected, do not
5369		 * send confirmation.
5370		 */
5371		if (hchan->state != BT_CONNECTED)
5372			break;
5373
5374		/* Logical link is already ready to go */
5375
5376		chan->hs_hcon = hchan->conn;
5377		chan->hs_hcon->l2cap_data = chan->conn;
5378
5379		if (result == L2CAP_MR_SUCCESS) {
5380			/* Can confirm now */
5381			l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
5382		} else {
5383			/* Now only need move success
5384			 * to confirm
5385			 */
5386			chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
5387		}
5388
5389		l2cap_logical_cfm(chan, hchan, L2CAP_MR_SUCCESS);
5390		break;
5391	default:
5392		/* Any other amp move state means the move failed. */
5393		chan->move_id = chan->local_amp_id;
5394		l2cap_move_done(chan);
5395		l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5396	}
5397
5398	l2cap_chan_unlock(chan);
5399}
5400
5401static void l2cap_move_fail(struct l2cap_conn *conn, u8 ident, u16 icid,
5402			    u16 result)
5403{
5404	struct l2cap_chan *chan;
5405
5406	chan = l2cap_get_chan_by_ident(conn, ident);
5407	if (!chan) {
5408		/* Could not locate channel, icid is best guess */
5409		l2cap_send_move_chan_cfm_icid(conn, icid);
5410		return;
5411	}
5412
5413	__clear_chan_timer(chan);
5414
5415	if (chan->move_role == L2CAP_MOVE_ROLE_INITIATOR) {
5416		if (result == L2CAP_MR_COLLISION) {
5417			chan->move_role = L2CAP_MOVE_ROLE_RESPONDER;
5418		} else {
5419			/* Cleanup - cancel move */
5420			chan->move_id = chan->local_amp_id;
5421			l2cap_move_done(chan);
5422		}
5423	}
5424
5425	l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5426
5427	l2cap_chan_unlock(chan);
5428}
5429
5430static int l2cap_move_channel_rsp(struct l2cap_conn *conn,
5431				  struct l2cap_cmd_hdr *cmd,
5432				  u16 cmd_len, void *data)
5433{
5434	struct l2cap_move_chan_rsp *rsp = data;
5435	u16 icid, result;
5436
5437	if (cmd_len != sizeof(*rsp))
5438		return -EPROTO;
5439
5440	icid = le16_to_cpu(rsp->icid);
5441	result = le16_to_cpu(rsp->result);
5442
5443	BT_DBG("icid 0x%4.4x, result 0x%4.4x", icid, result);
5444
5445	if (result == L2CAP_MR_SUCCESS || result == L2CAP_MR_PEND)
5446		l2cap_move_continue(conn, icid, result);
5447	else
5448		l2cap_move_fail(conn, cmd->ident, icid, result);
5449
5450	return 0;
5451}
5452
5453static int l2cap_move_channel_confirm(struct l2cap_conn *conn,
5454				      struct l2cap_cmd_hdr *cmd,
5455				      u16 cmd_len, void *data)
5456{
5457	struct l2cap_move_chan_cfm *cfm = data;
5458	struct l2cap_chan *chan;
5459	u16 icid, result;
5460
5461	if (cmd_len != sizeof(*cfm))
5462		return -EPROTO;
5463
5464	icid = le16_to_cpu(cfm->icid);
5465	result = le16_to_cpu(cfm->result);
5466
5467	BT_DBG("icid 0x%4.4x, result 0x%4.4x", icid, result);
5468
5469	chan = l2cap_get_chan_by_dcid(conn, icid);
5470	if (!chan) {
5471		/* Spec requires a response even if the icid was not found */
5472		l2cap_send_move_chan_cfm_rsp(conn, cmd->ident, icid);
5473		return 0;
5474	}
5475
5476	if (chan->move_state == L2CAP_MOVE_WAIT_CONFIRM) {
5477		if (result == L2CAP_MC_CONFIRMED) {
5478			chan->local_amp_id = chan->move_id;
5479			if (chan->local_amp_id == AMP_ID_BREDR)
5480				__release_logical_link(chan);
5481		} else {
5482			chan->move_id = chan->local_amp_id;
5483		}
5484
5485		l2cap_move_done(chan);
5486	}
5487
5488	l2cap_send_move_chan_cfm_rsp(conn, cmd->ident, icid);
5489
5490	l2cap_chan_unlock(chan);
5491
5492	return 0;
5493}
5494
5495static inline int l2cap_move_channel_confirm_rsp(struct l2cap_conn *conn,
5496						 struct l2cap_cmd_hdr *cmd,
5497						 u16 cmd_len, void *data)
5498{
5499	struct l2cap_move_chan_cfm_rsp *rsp = data;
5500	struct l2cap_chan *chan;
5501	u16 icid;
5502
5503	if (cmd_len != sizeof(*rsp))
5504		return -EPROTO;
5505
5506	icid = le16_to_cpu(rsp->icid);
5507
5508	BT_DBG("icid 0x%4.4x", icid);
5509
5510	chan = l2cap_get_chan_by_scid(conn, icid);
5511	if (!chan)
5512		return 0;
5513
5514	__clear_chan_timer(chan);
5515
5516	if (chan->move_state == L2CAP_MOVE_WAIT_CONFIRM_RSP) {
5517		chan->local_amp_id = chan->move_id;
5518
5519		if (chan->local_amp_id == AMP_ID_BREDR && chan->hs_hchan)
5520			__release_logical_link(chan);
5521
5522		l2cap_move_done(chan);
5523	}
5524
5525	l2cap_chan_unlock(chan);
5526
5527	return 0;
5528}
5529
5530static inline int l2cap_conn_param_update_req(struct l2cap_conn *conn,
5531					      struct l2cap_cmd_hdr *cmd,
5532					      u16 cmd_len, u8 *data)
5533{
5534	struct hci_conn *hcon = conn->hcon;
5535	struct l2cap_conn_param_update_req *req;
5536	struct l2cap_conn_param_update_rsp rsp;
5537	u16 min, max, latency, to_multiplier;
5538	int err;
5539
5540	if (hcon->role != HCI_ROLE_MASTER)
5541		return -EINVAL;
5542
5543	if (cmd_len != sizeof(struct l2cap_conn_param_update_req))
5544		return -EPROTO;
5545
5546	req = (struct l2cap_conn_param_update_req *) data;
5547	min		= __le16_to_cpu(req->min);
5548	max		= __le16_to_cpu(req->max);
5549	latency		= __le16_to_cpu(req->latency);
5550	to_multiplier	= __le16_to_cpu(req->to_multiplier);
5551
5552	BT_DBG("min 0x%4.4x max 0x%4.4x latency: 0x%4.4x Timeout: 0x%4.4x",
5553	       min, max, latency, to_multiplier);
5554
5555	memset(&rsp, 0, sizeof(rsp));
5556
5557	err = hci_check_conn_params(min, max, latency, to_multiplier);
5558	if (err)
5559		rsp.result = cpu_to_le16(L2CAP_CONN_PARAM_REJECTED);
5560	else
5561		rsp.result = cpu_to_le16(L2CAP_CONN_PARAM_ACCEPTED);
5562
5563	l2cap_send_cmd(conn, cmd->ident, L2CAP_CONN_PARAM_UPDATE_RSP,
5564		       sizeof(rsp), &rsp);
5565
5566	if (!err) {
5567		u8 store_hint;
5568
5569		store_hint = hci_le_conn_update(hcon, min, max, latency,
5570						to_multiplier);
5571		mgmt_new_conn_param(hcon->hdev, &hcon->dst, hcon->dst_type,
5572				    store_hint, min, max, latency,
5573				    to_multiplier);
5574
5575	}
5576
5577	return 0;
5578}
5579
5580static int l2cap_le_connect_rsp(struct l2cap_conn *conn,
5581				struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5582				u8 *data)
5583{
5584	struct l2cap_le_conn_rsp *rsp = (struct l2cap_le_conn_rsp *) data;
5585	struct hci_conn *hcon = conn->hcon;
5586	u16 dcid, mtu, mps, credits, result;
5587	struct l2cap_chan *chan;
5588	int err, sec_level;
5589
5590	if (cmd_len < sizeof(*rsp))
5591		return -EPROTO;
5592
5593	dcid    = __le16_to_cpu(rsp->dcid);
5594	mtu     = __le16_to_cpu(rsp->mtu);
5595	mps     = __le16_to_cpu(rsp->mps);
5596	credits = __le16_to_cpu(rsp->credits);
5597	result  = __le16_to_cpu(rsp->result);
5598
5599	if (result == L2CAP_CR_LE_SUCCESS && (mtu < 23 || mps < 23 ||
5600					   dcid < L2CAP_CID_DYN_START ||
5601					   dcid > L2CAP_CID_LE_DYN_END))
5602		return -EPROTO;
5603
5604	BT_DBG("dcid 0x%4.4x mtu %u mps %u credits %u result 0x%2.2x",
5605	       dcid, mtu, mps, credits, result);
5606
5607	mutex_lock(&conn->chan_lock);
5608
5609	chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
5610	if (!chan) {
5611		err = -EBADSLT;
5612		goto unlock;
5613	}
5614
5615	err = 0;
5616
5617	l2cap_chan_lock(chan);
5618
5619	switch (result) {
5620	case L2CAP_CR_LE_SUCCESS:
5621		if (__l2cap_get_chan_by_dcid(conn, dcid)) {
5622			err = -EBADSLT;
5623			break;
5624		}
5625
5626		chan->ident = 0;
5627		chan->dcid = dcid;
5628		chan->omtu = mtu;
5629		chan->remote_mps = mps;
5630		chan->tx_credits = credits;
5631		l2cap_chan_ready(chan);
5632		break;
5633
5634	case L2CAP_CR_LE_AUTHENTICATION:
5635	case L2CAP_CR_LE_ENCRYPTION:
5636		/* If we already have MITM protection we can't do
5637		 * anything.
5638		 */
5639		if (hcon->sec_level > BT_SECURITY_MEDIUM) {
5640			l2cap_chan_del(chan, ECONNREFUSED);
5641			break;
5642		}
5643
5644		sec_level = hcon->sec_level + 1;
5645		if (chan->sec_level < sec_level)
5646			chan->sec_level = sec_level;
5647
5648		/* We'll need to send a new Connect Request */
5649		clear_bit(FLAG_LE_CONN_REQ_SENT, &chan->flags);
5650
5651		smp_conn_security(hcon, chan->sec_level);
5652		break;
5653
5654	default:
5655		l2cap_chan_del(chan, ECONNREFUSED);
5656		break;
5657	}
5658
5659	l2cap_chan_unlock(chan);
5660
5661unlock:
5662	mutex_unlock(&conn->chan_lock);
5663
5664	return err;
5665}
5666
5667static inline int l2cap_bredr_sig_cmd(struct l2cap_conn *conn,
5668				      struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5669				      u8 *data)
5670{
5671	int err = 0;
5672
5673	switch (cmd->code) {
5674	case L2CAP_COMMAND_REJ:
5675		l2cap_command_rej(conn, cmd, cmd_len, data);
5676		break;
5677
5678	case L2CAP_CONN_REQ:
5679		err = l2cap_connect_req(conn, cmd, cmd_len, data);
5680		break;
5681
5682	case L2CAP_CONN_RSP:
5683	case L2CAP_CREATE_CHAN_RSP:
5684		l2cap_connect_create_rsp(conn, cmd, cmd_len, data);
5685		break;
5686
5687	case L2CAP_CONF_REQ:
5688		err = l2cap_config_req(conn, cmd, cmd_len, data);
5689		break;
5690
5691	case L2CAP_CONF_RSP:
5692		l2cap_config_rsp(conn, cmd, cmd_len, data);
5693		break;
5694
5695	case L2CAP_DISCONN_REQ:
5696		err = l2cap_disconnect_req(conn, cmd, cmd_len, data);
5697		break;
5698
5699	case L2CAP_DISCONN_RSP:
5700		l2cap_disconnect_rsp(conn, cmd, cmd_len, data);
5701		break;
5702
5703	case L2CAP_ECHO_REQ:
5704		l2cap_send_cmd(conn, cmd->ident, L2CAP_ECHO_RSP, cmd_len, data);
5705		break;
5706
5707	case L2CAP_ECHO_RSP:
5708		break;
5709
5710	case L2CAP_INFO_REQ:
5711		err = l2cap_information_req(conn, cmd, cmd_len, data);
5712		break;
5713
5714	case L2CAP_INFO_RSP:
5715		l2cap_information_rsp(conn, cmd, cmd_len, data);
5716		break;
5717
5718	case L2CAP_CREATE_CHAN_REQ:
5719		err = l2cap_create_channel_req(conn, cmd, cmd_len, data);
5720		break;
5721
5722	case L2CAP_MOVE_CHAN_REQ:
5723		err = l2cap_move_channel_req(conn, cmd, cmd_len, data);
5724		break;
5725
5726	case L2CAP_MOVE_CHAN_RSP:
5727		l2cap_move_channel_rsp(conn, cmd, cmd_len, data);
5728		break;
5729
5730	case L2CAP_MOVE_CHAN_CFM:
5731		err = l2cap_move_channel_confirm(conn, cmd, cmd_len, data);
5732		break;
5733
5734	case L2CAP_MOVE_CHAN_CFM_RSP:
5735		l2cap_move_channel_confirm_rsp(conn, cmd, cmd_len, data);
5736		break;
5737
5738	default:
5739		BT_ERR("Unknown BR/EDR signaling command 0x%2.2x", cmd->code);
5740		err = -EINVAL;
5741		break;
5742	}
5743
5744	return err;
5745}
5746
5747static int l2cap_le_connect_req(struct l2cap_conn *conn,
5748				struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5749				u8 *data)
5750{
5751	struct l2cap_le_conn_req *req = (struct l2cap_le_conn_req *) data;
5752	struct l2cap_le_conn_rsp rsp;
5753	struct l2cap_chan *chan, *pchan;
5754	u16 dcid, scid, credits, mtu, mps;
5755	__le16 psm;
5756	u8 result;
5757
5758	if (cmd_len != sizeof(*req))
5759		return -EPROTO;
5760
5761	scid = __le16_to_cpu(req->scid);
5762	mtu  = __le16_to_cpu(req->mtu);
5763	mps  = __le16_to_cpu(req->mps);
5764	psm  = req->psm;
5765	dcid = 0;
5766	credits = 0;
5767
5768	if (mtu < 23 || mps < 23)
5769		return -EPROTO;
5770
5771	BT_DBG("psm 0x%2.2x scid 0x%4.4x mtu %u mps %u", __le16_to_cpu(psm),
5772	       scid, mtu, mps);
5773
5774	/* Check if we have socket listening on psm */
5775	pchan = l2cap_global_chan_by_psm(BT_LISTEN, psm, &conn->hcon->src,
5776					 &conn->hcon->dst, LE_LINK);
5777	if (!pchan) {
5778		result = L2CAP_CR_LE_BAD_PSM;
5779		chan = NULL;
5780		goto response;
5781	}
5782
5783	mutex_lock(&conn->chan_lock);
5784	l2cap_chan_lock(pchan);
5785
5786	if (!smp_sufficient_security(conn->hcon, pchan->sec_level,
5787				     SMP_ALLOW_STK)) {
5788		result = L2CAP_CR_LE_AUTHENTICATION;
5789		chan = NULL;
5790		goto response_unlock;
5791	}
5792
5793	/* Check for valid dynamic CID range */
5794	if (scid < L2CAP_CID_DYN_START || scid > L2CAP_CID_LE_DYN_END) {
5795		result = L2CAP_CR_LE_INVALID_SCID;
5796		chan = NULL;
5797		goto response_unlock;
5798	}
5799
5800	/* Check if we already have channel with that dcid */
5801	if (__l2cap_get_chan_by_dcid(conn, scid)) {
5802		result = L2CAP_CR_LE_SCID_IN_USE;
5803		chan = NULL;
5804		goto response_unlock;
5805	}
5806
5807	chan = pchan->ops->new_connection(pchan);
5808	if (!chan) {
5809		result = L2CAP_CR_LE_NO_MEM;
5810		goto response_unlock;
5811	}
5812
 
 
5813	bacpy(&chan->src, &conn->hcon->src);
5814	bacpy(&chan->dst, &conn->hcon->dst);
5815	chan->src_type = bdaddr_src_type(conn->hcon);
5816	chan->dst_type = bdaddr_dst_type(conn->hcon);
5817	chan->psm  = psm;
5818	chan->dcid = scid;
5819	chan->omtu = mtu;
5820	chan->remote_mps = mps;
 
5821
5822	__l2cap_chan_add(conn, chan);
5823
5824	l2cap_le_flowctl_init(chan, __le16_to_cpu(req->credits));
5825
5826	dcid = chan->scid;
5827	credits = chan->rx_credits;
5828
5829	__set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
5830
5831	chan->ident = cmd->ident;
5832
5833	if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
5834		l2cap_state_change(chan, BT_CONNECT2);
5835		/* The following result value is actually not defined
5836		 * for LE CoC but we use it to let the function know
5837		 * that it should bail out after doing its cleanup
5838		 * instead of sending a response.
5839		 */
5840		result = L2CAP_CR_PEND;
5841		chan->ops->defer(chan);
5842	} else {
5843		l2cap_chan_ready(chan);
5844		result = L2CAP_CR_LE_SUCCESS;
5845	}
5846
5847response_unlock:
5848	l2cap_chan_unlock(pchan);
5849	mutex_unlock(&conn->chan_lock);
5850	l2cap_chan_put(pchan);
5851
5852	if (result == L2CAP_CR_PEND)
5853		return 0;
5854
5855response:
5856	if (chan) {
5857		rsp.mtu = cpu_to_le16(chan->imtu);
5858		rsp.mps = cpu_to_le16(chan->mps);
5859	} else {
5860		rsp.mtu = 0;
5861		rsp.mps = 0;
5862	}
5863
5864	rsp.dcid    = cpu_to_le16(dcid);
5865	rsp.credits = cpu_to_le16(credits);
5866	rsp.result  = cpu_to_le16(result);
5867
5868	l2cap_send_cmd(conn, cmd->ident, L2CAP_LE_CONN_RSP, sizeof(rsp), &rsp);
5869
5870	return 0;
5871}
5872
5873static inline int l2cap_le_credits(struct l2cap_conn *conn,
5874				   struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5875				   u8 *data)
5876{
5877	struct l2cap_le_credits *pkt;
5878	struct l2cap_chan *chan;
5879	u16 cid, credits, max_credits;
5880
5881	if (cmd_len != sizeof(*pkt))
5882		return -EPROTO;
5883
5884	pkt = (struct l2cap_le_credits *) data;
5885	cid	= __le16_to_cpu(pkt->cid);
5886	credits	= __le16_to_cpu(pkt->credits);
5887
5888	BT_DBG("cid 0x%4.4x credits 0x%4.4x", cid, credits);
5889
5890	chan = l2cap_get_chan_by_dcid(conn, cid);
5891	if (!chan)
5892		return -EBADSLT;
5893
5894	max_credits = LE_FLOWCTL_MAX_CREDITS - chan->tx_credits;
5895	if (credits > max_credits) {
5896		BT_ERR("LE credits overflow");
5897		l2cap_send_disconn_req(chan, ECONNRESET);
5898		l2cap_chan_unlock(chan);
5899
5900		/* Return 0 so that we don't trigger an unnecessary
5901		 * command reject packet.
5902		 */
5903		return 0;
5904	}
5905
5906	chan->tx_credits += credits;
5907
5908	/* Resume sending */
5909	l2cap_le_flowctl_send(chan);
 
 
5910
5911	if (chan->tx_credits)
5912		chan->ops->resume(chan);
5913
5914	l2cap_chan_unlock(chan);
5915
5916	return 0;
5917}
5918
5919static inline int l2cap_ecred_conn_req(struct l2cap_conn *conn,
5920				       struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5921				       u8 *data)
5922{
5923	struct l2cap_ecred_conn_req *req = (void *) data;
5924	struct {
5925		struct l2cap_ecred_conn_rsp rsp;
5926		__le16 dcid[L2CAP_ECRED_MAX_CID];
5927	} __packed pdu;
5928	struct l2cap_chan *chan, *pchan;
5929	u16 mtu, mps;
5930	__le16 psm;
5931	u8 result, len = 0;
5932	int i, num_scid;
5933	bool defer = false;
5934
5935	if (!enable_ecred)
5936		return -EINVAL;
5937
5938	if (cmd_len < sizeof(*req) || (cmd_len - sizeof(*req)) % sizeof(u16)) {
5939		result = L2CAP_CR_LE_INVALID_PARAMS;
5940		goto response;
5941	}
5942
5943	cmd_len -= sizeof(*req);
5944	num_scid = cmd_len / sizeof(u16);
5945
5946	if (num_scid > ARRAY_SIZE(pdu.dcid)) {
5947		result = L2CAP_CR_LE_INVALID_PARAMS;
5948		goto response;
5949	}
5950
5951	mtu  = __le16_to_cpu(req->mtu);
5952	mps  = __le16_to_cpu(req->mps);
5953
5954	if (mtu < L2CAP_ECRED_MIN_MTU || mps < L2CAP_ECRED_MIN_MPS) {
5955		result = L2CAP_CR_LE_UNACCEPT_PARAMS;
5956		goto response;
5957	}
5958
5959	psm  = req->psm;
5960
5961	BT_DBG("psm 0x%2.2x mtu %u mps %u", __le16_to_cpu(psm), mtu, mps);
5962
5963	memset(&pdu, 0, sizeof(pdu));
5964
5965	/* Check if we have socket listening on psm */
5966	pchan = l2cap_global_chan_by_psm(BT_LISTEN, psm, &conn->hcon->src,
5967					 &conn->hcon->dst, LE_LINK);
5968	if (!pchan) {
5969		result = L2CAP_CR_LE_BAD_PSM;
5970		goto response;
5971	}
5972
5973	mutex_lock(&conn->chan_lock);
5974	l2cap_chan_lock(pchan);
5975
5976	if (!smp_sufficient_security(conn->hcon, pchan->sec_level,
5977				     SMP_ALLOW_STK)) {
5978		result = L2CAP_CR_LE_AUTHENTICATION;
5979		goto unlock;
5980	}
5981
5982	result = L2CAP_CR_LE_SUCCESS;
5983
5984	for (i = 0; i < num_scid; i++) {
5985		u16 scid = __le16_to_cpu(req->scid[i]);
5986
5987		BT_DBG("scid[%d] 0x%4.4x", i, scid);
5988
5989		pdu.dcid[i] = 0x0000;
5990		len += sizeof(*pdu.dcid);
5991
5992		/* Check for valid dynamic CID range */
5993		if (scid < L2CAP_CID_DYN_START || scid > L2CAP_CID_LE_DYN_END) {
5994			result = L2CAP_CR_LE_INVALID_SCID;
5995			continue;
5996		}
5997
5998		/* Check if we already have channel with that dcid */
5999		if (__l2cap_get_chan_by_dcid(conn, scid)) {
6000			result = L2CAP_CR_LE_SCID_IN_USE;
6001			continue;
6002		}
6003
6004		chan = pchan->ops->new_connection(pchan);
6005		if (!chan) {
6006			result = L2CAP_CR_LE_NO_MEM;
6007			continue;
6008		}
6009
6010		bacpy(&chan->src, &conn->hcon->src);
6011		bacpy(&chan->dst, &conn->hcon->dst);
6012		chan->src_type = bdaddr_src_type(conn->hcon);
6013		chan->dst_type = bdaddr_dst_type(conn->hcon);
6014		chan->psm  = psm;
6015		chan->dcid = scid;
6016		chan->omtu = mtu;
6017		chan->remote_mps = mps;
6018
6019		__l2cap_chan_add(conn, chan);
6020
6021		l2cap_ecred_init(chan, __le16_to_cpu(req->credits));
6022
6023		/* Init response */
6024		if (!pdu.rsp.credits) {
6025			pdu.rsp.mtu = cpu_to_le16(chan->imtu);
6026			pdu.rsp.mps = cpu_to_le16(chan->mps);
6027			pdu.rsp.credits = cpu_to_le16(chan->rx_credits);
6028		}
6029
6030		pdu.dcid[i] = cpu_to_le16(chan->scid);
6031
6032		__set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
6033
6034		chan->ident = cmd->ident;
6035
6036		if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
6037			l2cap_state_change(chan, BT_CONNECT2);
6038			defer = true;
6039			chan->ops->defer(chan);
6040		} else {
6041			l2cap_chan_ready(chan);
6042		}
6043	}
6044
6045unlock:
6046	l2cap_chan_unlock(pchan);
6047	mutex_unlock(&conn->chan_lock);
6048	l2cap_chan_put(pchan);
6049
6050response:
6051	pdu.rsp.result = cpu_to_le16(result);
6052
6053	if (defer)
6054		return 0;
6055
6056	l2cap_send_cmd(conn, cmd->ident, L2CAP_ECRED_CONN_RSP,
6057		       sizeof(pdu.rsp) + len, &pdu);
6058
6059	return 0;
6060}
6061
6062static inline int l2cap_ecred_conn_rsp(struct l2cap_conn *conn,
6063				       struct l2cap_cmd_hdr *cmd, u16 cmd_len,
6064				       u8 *data)
6065{
6066	struct l2cap_ecred_conn_rsp *rsp = (void *) data;
6067	struct hci_conn *hcon = conn->hcon;
6068	u16 mtu, mps, credits, result;
6069	struct l2cap_chan *chan, *tmp;
6070	int err = 0, sec_level;
6071	int i = 0;
6072
6073	if (cmd_len < sizeof(*rsp))
6074		return -EPROTO;
6075
6076	mtu     = __le16_to_cpu(rsp->mtu);
6077	mps     = __le16_to_cpu(rsp->mps);
6078	credits = __le16_to_cpu(rsp->credits);
6079	result  = __le16_to_cpu(rsp->result);
6080
6081	BT_DBG("mtu %u mps %u credits %u result 0x%4.4x", mtu, mps, credits,
6082	       result);
6083
6084	mutex_lock(&conn->chan_lock);
6085
6086	cmd_len -= sizeof(*rsp);
6087
6088	list_for_each_entry_safe(chan, tmp, &conn->chan_l, list) {
6089		u16 dcid;
6090
6091		if (chan->ident != cmd->ident ||
6092		    chan->mode != L2CAP_MODE_EXT_FLOWCTL ||
6093		    chan->state == BT_CONNECTED)
6094			continue;
6095
6096		l2cap_chan_lock(chan);
6097
6098		/* Check that there is a dcid for each pending channel */
6099		if (cmd_len < sizeof(dcid)) {
6100			l2cap_chan_del(chan, ECONNREFUSED);
6101			l2cap_chan_unlock(chan);
6102			continue;
6103		}
6104
6105		dcid = __le16_to_cpu(rsp->dcid[i++]);
6106		cmd_len -= sizeof(u16);
6107
6108		BT_DBG("dcid[%d] 0x%4.4x", i, dcid);
6109
6110		/* Check if dcid is already in use */
6111		if (dcid && __l2cap_get_chan_by_dcid(conn, dcid)) {
6112			/* If a device receives a
6113			 * L2CAP_CREDIT_BASED_CONNECTION_RSP packet with an
6114			 * already-assigned Destination CID, then both the
6115			 * original channel and the new channel shall be
6116			 * immediately discarded and not used.
6117			 */
6118			l2cap_chan_del(chan, ECONNREFUSED);
6119			l2cap_chan_unlock(chan);
6120			chan = __l2cap_get_chan_by_dcid(conn, dcid);
6121			l2cap_chan_lock(chan);
6122			l2cap_chan_del(chan, ECONNRESET);
6123			l2cap_chan_unlock(chan);
6124			continue;
6125		}
6126
6127		switch (result) {
6128		case L2CAP_CR_LE_AUTHENTICATION:
6129		case L2CAP_CR_LE_ENCRYPTION:
6130			/* If we already have MITM protection we can't do
6131			 * anything.
6132			 */
6133			if (hcon->sec_level > BT_SECURITY_MEDIUM) {
6134				l2cap_chan_del(chan, ECONNREFUSED);
6135				break;
6136			}
6137
6138			sec_level = hcon->sec_level + 1;
6139			if (chan->sec_level < sec_level)
6140				chan->sec_level = sec_level;
6141
6142			/* We'll need to send a new Connect Request */
6143			clear_bit(FLAG_ECRED_CONN_REQ_SENT, &chan->flags);
6144
6145			smp_conn_security(hcon, chan->sec_level);
6146			break;
6147
6148		case L2CAP_CR_LE_BAD_PSM:
6149			l2cap_chan_del(chan, ECONNREFUSED);
6150			break;
6151
6152		default:
6153			/* If dcid was not set it means channels was refused */
6154			if (!dcid) {
6155				l2cap_chan_del(chan, ECONNREFUSED);
6156				break;
6157			}
6158
6159			chan->ident = 0;
6160			chan->dcid = dcid;
6161			chan->omtu = mtu;
6162			chan->remote_mps = mps;
6163			chan->tx_credits = credits;
6164			l2cap_chan_ready(chan);
6165			break;
6166		}
6167
6168		l2cap_chan_unlock(chan);
6169	}
6170
6171	mutex_unlock(&conn->chan_lock);
6172
6173	return err;
6174}
6175
6176static inline int l2cap_ecred_reconf_req(struct l2cap_conn *conn,
6177					 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
6178					 u8 *data)
6179{
6180	struct l2cap_ecred_reconf_req *req = (void *) data;
6181	struct l2cap_ecred_reconf_rsp rsp;
6182	u16 mtu, mps, result;
6183	struct l2cap_chan *chan;
6184	int i, num_scid;
6185
6186	if (!enable_ecred)
6187		return -EINVAL;
6188
6189	if (cmd_len < sizeof(*req) || cmd_len - sizeof(*req) % sizeof(u16)) {
6190		result = L2CAP_CR_LE_INVALID_PARAMS;
6191		goto respond;
6192	}
6193
6194	mtu = __le16_to_cpu(req->mtu);
6195	mps = __le16_to_cpu(req->mps);
6196
6197	BT_DBG("mtu %u mps %u", mtu, mps);
6198
6199	if (mtu < L2CAP_ECRED_MIN_MTU) {
6200		result = L2CAP_RECONF_INVALID_MTU;
6201		goto respond;
6202	}
6203
6204	if (mps < L2CAP_ECRED_MIN_MPS) {
6205		result = L2CAP_RECONF_INVALID_MPS;
6206		goto respond;
6207	}
6208
6209	cmd_len -= sizeof(*req);
6210	num_scid = cmd_len / sizeof(u16);
6211	result = L2CAP_RECONF_SUCCESS;
6212
6213	for (i = 0; i < num_scid; i++) {
6214		u16 scid;
6215
6216		scid = __le16_to_cpu(req->scid[i]);
6217		if (!scid)
6218			return -EPROTO;
6219
6220		chan = __l2cap_get_chan_by_dcid(conn, scid);
6221		if (!chan)
6222			continue;
6223
6224		/* If the MTU value is decreased for any of the included
6225		 * channels, then the receiver shall disconnect all
6226		 * included channels.
6227		 */
6228		if (chan->omtu > mtu) {
6229			BT_ERR("chan %p decreased MTU %u -> %u", chan,
6230			       chan->omtu, mtu);
6231			result = L2CAP_RECONF_INVALID_MTU;
6232		}
6233
6234		chan->omtu = mtu;
6235		chan->remote_mps = mps;
6236	}
6237
6238respond:
6239	rsp.result = cpu_to_le16(result);
6240
6241	l2cap_send_cmd(conn, cmd->ident, L2CAP_ECRED_RECONF_RSP, sizeof(rsp),
6242		       &rsp);
6243
6244	return 0;
6245}
6246
6247static inline int l2cap_ecred_reconf_rsp(struct l2cap_conn *conn,
6248					 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
6249					 u8 *data)
6250{
6251	struct l2cap_chan *chan, *tmp;
6252	struct l2cap_ecred_conn_rsp *rsp = (void *) data;
6253	u16 result;
6254
6255	if (cmd_len < sizeof(*rsp))
6256		return -EPROTO;
6257
6258	result = __le16_to_cpu(rsp->result);
6259
6260	BT_DBG("result 0x%4.4x", rsp->result);
6261
6262	if (!result)
6263		return 0;
6264
6265	list_for_each_entry_safe(chan, tmp, &conn->chan_l, list) {
6266		if (chan->ident != cmd->ident)
6267			continue;
6268
6269		l2cap_chan_del(chan, ECONNRESET);
6270	}
6271
6272	return 0;
6273}
6274
6275static inline int l2cap_le_command_rej(struct l2cap_conn *conn,
6276				       struct l2cap_cmd_hdr *cmd, u16 cmd_len,
6277				       u8 *data)
6278{
6279	struct l2cap_cmd_rej_unk *rej = (struct l2cap_cmd_rej_unk *) data;
6280	struct l2cap_chan *chan;
6281
6282	if (cmd_len < sizeof(*rej))
6283		return -EPROTO;
6284
6285	mutex_lock(&conn->chan_lock);
6286
6287	chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
6288	if (!chan)
6289		goto done;
6290
6291	l2cap_chan_lock(chan);
6292	l2cap_chan_del(chan, ECONNREFUSED);
6293	l2cap_chan_unlock(chan);
6294
6295done:
6296	mutex_unlock(&conn->chan_lock);
6297	return 0;
6298}
6299
6300static inline int l2cap_le_sig_cmd(struct l2cap_conn *conn,
6301				   struct l2cap_cmd_hdr *cmd, u16 cmd_len,
6302				   u8 *data)
6303{
6304	int err = 0;
6305
6306	switch (cmd->code) {
6307	case L2CAP_COMMAND_REJ:
6308		l2cap_le_command_rej(conn, cmd, cmd_len, data);
6309		break;
6310
6311	case L2CAP_CONN_PARAM_UPDATE_REQ:
6312		err = l2cap_conn_param_update_req(conn, cmd, cmd_len, data);
6313		break;
6314
6315	case L2CAP_CONN_PARAM_UPDATE_RSP:
6316		break;
6317
6318	case L2CAP_LE_CONN_RSP:
6319		l2cap_le_connect_rsp(conn, cmd, cmd_len, data);
6320		break;
6321
6322	case L2CAP_LE_CONN_REQ:
6323		err = l2cap_le_connect_req(conn, cmd, cmd_len, data);
6324		break;
6325
6326	case L2CAP_LE_CREDITS:
6327		err = l2cap_le_credits(conn, cmd, cmd_len, data);
6328		break;
6329
6330	case L2CAP_ECRED_CONN_REQ:
6331		err = l2cap_ecred_conn_req(conn, cmd, cmd_len, data);
6332		break;
6333
6334	case L2CAP_ECRED_CONN_RSP:
6335		err = l2cap_ecred_conn_rsp(conn, cmd, cmd_len, data);
6336		break;
6337
6338	case L2CAP_ECRED_RECONF_REQ:
6339		err = l2cap_ecred_reconf_req(conn, cmd, cmd_len, data);
6340		break;
6341
6342	case L2CAP_ECRED_RECONF_RSP:
6343		err = l2cap_ecred_reconf_rsp(conn, cmd, cmd_len, data);
6344		break;
6345
6346	case L2CAP_DISCONN_REQ:
6347		err = l2cap_disconnect_req(conn, cmd, cmd_len, data);
6348		break;
6349
6350	case L2CAP_DISCONN_RSP:
6351		l2cap_disconnect_rsp(conn, cmd, cmd_len, data);
6352		break;
6353
6354	default:
6355		BT_ERR("Unknown LE signaling command 0x%2.2x", cmd->code);
6356		err = -EINVAL;
6357		break;
6358	}
6359
6360	return err;
6361}
6362
6363static inline void l2cap_le_sig_channel(struct l2cap_conn *conn,
6364					struct sk_buff *skb)
6365{
6366	struct hci_conn *hcon = conn->hcon;
6367	struct l2cap_cmd_hdr *cmd;
6368	u16 len;
6369	int err;
6370
6371	if (hcon->type != LE_LINK)
6372		goto drop;
6373
6374	if (skb->len < L2CAP_CMD_HDR_SIZE)
6375		goto drop;
6376
6377	cmd = (void *) skb->data;
6378	skb_pull(skb, L2CAP_CMD_HDR_SIZE);
6379
6380	len = le16_to_cpu(cmd->len);
6381
6382	BT_DBG("code 0x%2.2x len %d id 0x%2.2x", cmd->code, len, cmd->ident);
6383
6384	if (len != skb->len || !cmd->ident) {
6385		BT_DBG("corrupted command");
6386		goto drop;
6387	}
6388
6389	err = l2cap_le_sig_cmd(conn, cmd, len, skb->data);
6390	if (err) {
6391		struct l2cap_cmd_rej_unk rej;
6392
6393		BT_ERR("Wrong link type (%d)", err);
6394
6395		rej.reason = cpu_to_le16(L2CAP_REJ_NOT_UNDERSTOOD);
6396		l2cap_send_cmd(conn, cmd->ident, L2CAP_COMMAND_REJ,
6397			       sizeof(rej), &rej);
6398	}
6399
6400drop:
6401	kfree_skb(skb);
6402}
6403
6404static inline void l2cap_sig_channel(struct l2cap_conn *conn,
6405				     struct sk_buff *skb)
6406{
6407	struct hci_conn *hcon = conn->hcon;
6408	struct l2cap_cmd_hdr *cmd;
 
 
6409	int err;
6410
6411	l2cap_raw_recv(conn, skb);
6412
6413	if (hcon->type != ACL_LINK)
6414		goto drop;
6415
6416	while (skb->len >= L2CAP_CMD_HDR_SIZE) {
6417		u16 len;
6418
6419		cmd = (void *) skb->data;
6420		skb_pull(skb, L2CAP_CMD_HDR_SIZE);
6421
6422		len = le16_to_cpu(cmd->len);
6423
6424		BT_DBG("code 0x%2.2x len %d id 0x%2.2x", cmd->code, len,
6425		       cmd->ident);
6426
6427		if (len > skb->len || !cmd->ident) {
6428			BT_DBG("corrupted command");
6429			break;
6430		}
6431
6432		err = l2cap_bredr_sig_cmd(conn, cmd, len, skb->data);
6433		if (err) {
6434			struct l2cap_cmd_rej_unk rej;
6435
6436			BT_ERR("Wrong link type (%d)", err);
6437
6438			rej.reason = cpu_to_le16(L2CAP_REJ_NOT_UNDERSTOOD);
6439			l2cap_send_cmd(conn, cmd->ident, L2CAP_COMMAND_REJ,
6440				       sizeof(rej), &rej);
6441		}
6442
6443		skb_pull(skb, len);
 
6444	}
6445
6446drop:
6447	kfree_skb(skb);
6448}
6449
6450static int l2cap_check_fcs(struct l2cap_chan *chan,  struct sk_buff *skb)
6451{
6452	u16 our_fcs, rcv_fcs;
6453	int hdr_size;
6454
6455	if (test_bit(FLAG_EXT_CTRL, &chan->flags))
6456		hdr_size = L2CAP_EXT_HDR_SIZE;
6457	else
6458		hdr_size = L2CAP_ENH_HDR_SIZE;
6459
6460	if (chan->fcs == L2CAP_FCS_CRC16) {
6461		skb_trim(skb, skb->len - L2CAP_FCS_SIZE);
6462		rcv_fcs = get_unaligned_le16(skb->data + skb->len);
6463		our_fcs = crc16(0, skb->data - hdr_size, skb->len + hdr_size);
6464
6465		if (our_fcs != rcv_fcs)
6466			return -EBADMSG;
6467	}
6468	return 0;
6469}
6470
6471static void l2cap_send_i_or_rr_or_rnr(struct l2cap_chan *chan)
6472{
6473	struct l2cap_ctrl control;
6474
6475	BT_DBG("chan %p", chan);
6476
6477	memset(&control, 0, sizeof(control));
6478	control.sframe = 1;
6479	control.final = 1;
6480	control.reqseq = chan->buffer_seq;
6481	set_bit(CONN_SEND_FBIT, &chan->conn_state);
6482
6483	if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
6484		control.super = L2CAP_SUPER_RNR;
6485		l2cap_send_sframe(chan, &control);
6486	}
6487
6488	if (test_and_clear_bit(CONN_REMOTE_BUSY, &chan->conn_state) &&
6489	    chan->unacked_frames > 0)
6490		__set_retrans_timer(chan);
6491
6492	/* Send pending iframes */
6493	l2cap_ertm_send(chan);
6494
6495	if (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state) &&
6496	    test_bit(CONN_SEND_FBIT, &chan->conn_state)) {
6497		/* F-bit wasn't sent in an s-frame or i-frame yet, so
6498		 * send it now.
6499		 */
6500		control.super = L2CAP_SUPER_RR;
6501		l2cap_send_sframe(chan, &control);
6502	}
6503}
6504
6505static void append_skb_frag(struct sk_buff *skb, struct sk_buff *new_frag,
6506			    struct sk_buff **last_frag)
6507{
6508	/* skb->len reflects data in skb as well as all fragments
6509	 * skb->data_len reflects only data in fragments
6510	 */
6511	if (!skb_has_frag_list(skb))
6512		skb_shinfo(skb)->frag_list = new_frag;
6513
6514	new_frag->next = NULL;
6515
6516	(*last_frag)->next = new_frag;
6517	*last_frag = new_frag;
6518
6519	skb->len += new_frag->len;
6520	skb->data_len += new_frag->len;
6521	skb->truesize += new_frag->truesize;
6522}
6523
6524static int l2cap_reassemble_sdu(struct l2cap_chan *chan, struct sk_buff *skb,
6525				struct l2cap_ctrl *control)
6526{
6527	int err = -EINVAL;
6528
6529	switch (control->sar) {
6530	case L2CAP_SAR_UNSEGMENTED:
6531		if (chan->sdu)
6532			break;
6533
6534		err = chan->ops->recv(chan, skb);
6535		break;
6536
6537	case L2CAP_SAR_START:
6538		if (chan->sdu)
6539			break;
6540
6541		if (!pskb_may_pull(skb, L2CAP_SDULEN_SIZE))
6542			break;
6543
6544		chan->sdu_len = get_unaligned_le16(skb->data);
6545		skb_pull(skb, L2CAP_SDULEN_SIZE);
6546
6547		if (chan->sdu_len > chan->imtu) {
6548			err = -EMSGSIZE;
6549			break;
6550		}
6551
6552		if (skb->len >= chan->sdu_len)
6553			break;
6554
6555		chan->sdu = skb;
6556		chan->sdu_last_frag = skb;
6557
6558		skb = NULL;
6559		err = 0;
6560		break;
6561
6562	case L2CAP_SAR_CONTINUE:
6563		if (!chan->sdu)
6564			break;
6565
6566		append_skb_frag(chan->sdu, skb,
6567				&chan->sdu_last_frag);
6568		skb = NULL;
6569
6570		if (chan->sdu->len >= chan->sdu_len)
6571			break;
6572
6573		err = 0;
6574		break;
6575
6576	case L2CAP_SAR_END:
6577		if (!chan->sdu)
6578			break;
6579
6580		append_skb_frag(chan->sdu, skb,
6581				&chan->sdu_last_frag);
6582		skb = NULL;
6583
6584		if (chan->sdu->len != chan->sdu_len)
6585			break;
6586
6587		err = chan->ops->recv(chan, chan->sdu);
6588
6589		if (!err) {
6590			/* Reassembly complete */
6591			chan->sdu = NULL;
6592			chan->sdu_last_frag = NULL;
6593			chan->sdu_len = 0;
6594		}
6595		break;
6596	}
6597
6598	if (err) {
6599		kfree_skb(skb);
6600		kfree_skb(chan->sdu);
6601		chan->sdu = NULL;
6602		chan->sdu_last_frag = NULL;
6603		chan->sdu_len = 0;
6604	}
6605
6606	return err;
6607}
6608
6609static int l2cap_resegment(struct l2cap_chan *chan)
6610{
6611	/* Placeholder */
6612	return 0;
6613}
6614
6615void l2cap_chan_busy(struct l2cap_chan *chan, int busy)
6616{
6617	u8 event;
6618
6619	if (chan->mode != L2CAP_MODE_ERTM)
6620		return;
6621
6622	event = busy ? L2CAP_EV_LOCAL_BUSY_DETECTED : L2CAP_EV_LOCAL_BUSY_CLEAR;
6623	l2cap_tx(chan, NULL, NULL, event);
6624}
6625
6626static int l2cap_rx_queued_iframes(struct l2cap_chan *chan)
6627{
6628	int err = 0;
6629	/* Pass sequential frames to l2cap_reassemble_sdu()
6630	 * until a gap is encountered.
6631	 */
6632
6633	BT_DBG("chan %p", chan);
6634
6635	while (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
6636		struct sk_buff *skb;
6637		BT_DBG("Searching for skb with txseq %d (queue len %d)",
6638		       chan->buffer_seq, skb_queue_len(&chan->srej_q));
6639
6640		skb = l2cap_ertm_seq_in_queue(&chan->srej_q, chan->buffer_seq);
6641
6642		if (!skb)
6643			break;
6644
6645		skb_unlink(skb, &chan->srej_q);
6646		chan->buffer_seq = __next_seq(chan, chan->buffer_seq);
6647		err = l2cap_reassemble_sdu(chan, skb, &bt_cb(skb)->l2cap);
6648		if (err)
6649			break;
6650	}
6651
6652	if (skb_queue_empty(&chan->srej_q)) {
6653		chan->rx_state = L2CAP_RX_STATE_RECV;
6654		l2cap_send_ack(chan);
6655	}
6656
6657	return err;
6658}
6659
6660static void l2cap_handle_srej(struct l2cap_chan *chan,
6661			      struct l2cap_ctrl *control)
6662{
6663	struct sk_buff *skb;
6664
6665	BT_DBG("chan %p, control %p", chan, control);
6666
6667	if (control->reqseq == chan->next_tx_seq) {
6668		BT_DBG("Invalid reqseq %d, disconnecting", control->reqseq);
6669		l2cap_send_disconn_req(chan, ECONNRESET);
6670		return;
6671	}
6672
6673	skb = l2cap_ertm_seq_in_queue(&chan->tx_q, control->reqseq);
6674
6675	if (skb == NULL) {
6676		BT_DBG("Seq %d not available for retransmission",
6677		       control->reqseq);
6678		return;
6679	}
6680
6681	if (chan->max_tx != 0 && bt_cb(skb)->l2cap.retries >= chan->max_tx) {
6682		BT_DBG("Retry limit exceeded (%d)", chan->max_tx);
6683		l2cap_send_disconn_req(chan, ECONNRESET);
6684		return;
6685	}
6686
6687	clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6688
6689	if (control->poll) {
6690		l2cap_pass_to_tx(chan, control);
6691
6692		set_bit(CONN_SEND_FBIT, &chan->conn_state);
6693		l2cap_retransmit(chan, control);
6694		l2cap_ertm_send(chan);
6695
6696		if (chan->tx_state == L2CAP_TX_STATE_WAIT_F) {
6697			set_bit(CONN_SREJ_ACT, &chan->conn_state);
6698			chan->srej_save_reqseq = control->reqseq;
6699		}
6700	} else {
6701		l2cap_pass_to_tx_fbit(chan, control);
6702
6703		if (control->final) {
6704			if (chan->srej_save_reqseq != control->reqseq ||
6705			    !test_and_clear_bit(CONN_SREJ_ACT,
6706						&chan->conn_state))
6707				l2cap_retransmit(chan, control);
6708		} else {
6709			l2cap_retransmit(chan, control);
6710			if (chan->tx_state == L2CAP_TX_STATE_WAIT_F) {
6711				set_bit(CONN_SREJ_ACT, &chan->conn_state);
6712				chan->srej_save_reqseq = control->reqseq;
6713			}
6714		}
6715	}
6716}
6717
6718static void l2cap_handle_rej(struct l2cap_chan *chan,
6719			     struct l2cap_ctrl *control)
6720{
6721	struct sk_buff *skb;
6722
6723	BT_DBG("chan %p, control %p", chan, control);
6724
6725	if (control->reqseq == chan->next_tx_seq) {
6726		BT_DBG("Invalid reqseq %d, disconnecting", control->reqseq);
6727		l2cap_send_disconn_req(chan, ECONNRESET);
6728		return;
6729	}
6730
6731	skb = l2cap_ertm_seq_in_queue(&chan->tx_q, control->reqseq);
6732
6733	if (chan->max_tx && skb &&
6734	    bt_cb(skb)->l2cap.retries >= chan->max_tx) {
6735		BT_DBG("Retry limit exceeded (%d)", chan->max_tx);
6736		l2cap_send_disconn_req(chan, ECONNRESET);
6737		return;
6738	}
6739
6740	clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6741
6742	l2cap_pass_to_tx(chan, control);
6743
6744	if (control->final) {
6745		if (!test_and_clear_bit(CONN_REJ_ACT, &chan->conn_state))
6746			l2cap_retransmit_all(chan, control);
6747	} else {
6748		l2cap_retransmit_all(chan, control);
6749		l2cap_ertm_send(chan);
6750		if (chan->tx_state == L2CAP_TX_STATE_WAIT_F)
6751			set_bit(CONN_REJ_ACT, &chan->conn_state);
6752	}
6753}
6754
6755static u8 l2cap_classify_txseq(struct l2cap_chan *chan, u16 txseq)
6756{
6757	BT_DBG("chan %p, txseq %d", chan, txseq);
6758
6759	BT_DBG("last_acked_seq %d, expected_tx_seq %d", chan->last_acked_seq,
6760	       chan->expected_tx_seq);
6761
6762	if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) {
6763		if (__seq_offset(chan, txseq, chan->last_acked_seq) >=
6764		    chan->tx_win) {
6765			/* See notes below regarding "double poll" and
6766			 * invalid packets.
6767			 */
6768			if (chan->tx_win <= ((chan->tx_win_max + 1) >> 1)) {
6769				BT_DBG("Invalid/Ignore - after SREJ");
6770				return L2CAP_TXSEQ_INVALID_IGNORE;
6771			} else {
6772				BT_DBG("Invalid - in window after SREJ sent");
6773				return L2CAP_TXSEQ_INVALID;
6774			}
6775		}
6776
6777		if (chan->srej_list.head == txseq) {
6778			BT_DBG("Expected SREJ");
6779			return L2CAP_TXSEQ_EXPECTED_SREJ;
6780		}
6781
6782		if (l2cap_ertm_seq_in_queue(&chan->srej_q, txseq)) {
6783			BT_DBG("Duplicate SREJ - txseq already stored");
6784			return L2CAP_TXSEQ_DUPLICATE_SREJ;
6785		}
6786
6787		if (l2cap_seq_list_contains(&chan->srej_list, txseq)) {
6788			BT_DBG("Unexpected SREJ - not requested");
6789			return L2CAP_TXSEQ_UNEXPECTED_SREJ;
6790		}
6791	}
6792
6793	if (chan->expected_tx_seq == txseq) {
6794		if (__seq_offset(chan, txseq, chan->last_acked_seq) >=
6795		    chan->tx_win) {
6796			BT_DBG("Invalid - txseq outside tx window");
6797			return L2CAP_TXSEQ_INVALID;
6798		} else {
6799			BT_DBG("Expected");
6800			return L2CAP_TXSEQ_EXPECTED;
6801		}
6802	}
6803
6804	if (__seq_offset(chan, txseq, chan->last_acked_seq) <
6805	    __seq_offset(chan, chan->expected_tx_seq, chan->last_acked_seq)) {
6806		BT_DBG("Duplicate - expected_tx_seq later than txseq");
6807		return L2CAP_TXSEQ_DUPLICATE;
6808	}
6809
6810	if (__seq_offset(chan, txseq, chan->last_acked_seq) >= chan->tx_win) {
6811		/* A source of invalid packets is a "double poll" condition,
6812		 * where delays cause us to send multiple poll packets.  If
6813		 * the remote stack receives and processes both polls,
6814		 * sequence numbers can wrap around in such a way that a
6815		 * resent frame has a sequence number that looks like new data
6816		 * with a sequence gap.  This would trigger an erroneous SREJ
6817		 * request.
6818		 *
6819		 * Fortunately, this is impossible with a tx window that's
6820		 * less than half of the maximum sequence number, which allows
6821		 * invalid frames to be safely ignored.
6822		 *
6823		 * With tx window sizes greater than half of the tx window
6824		 * maximum, the frame is invalid and cannot be ignored.  This
6825		 * causes a disconnect.
6826		 */
6827
6828		if (chan->tx_win <= ((chan->tx_win_max + 1) >> 1)) {
6829			BT_DBG("Invalid/Ignore - txseq outside tx window");
6830			return L2CAP_TXSEQ_INVALID_IGNORE;
6831		} else {
6832			BT_DBG("Invalid - txseq outside tx window");
6833			return L2CAP_TXSEQ_INVALID;
6834		}
6835	} else {
6836		BT_DBG("Unexpected - txseq indicates missing frames");
6837		return L2CAP_TXSEQ_UNEXPECTED;
6838	}
6839}
6840
6841static int l2cap_rx_state_recv(struct l2cap_chan *chan,
6842			       struct l2cap_ctrl *control,
6843			       struct sk_buff *skb, u8 event)
6844{
6845	int err = 0;
6846	bool skb_in_use = false;
6847
6848	BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
6849	       event);
6850
6851	switch (event) {
6852	case L2CAP_EV_RECV_IFRAME:
6853		switch (l2cap_classify_txseq(chan, control->txseq)) {
6854		case L2CAP_TXSEQ_EXPECTED:
6855			l2cap_pass_to_tx(chan, control);
6856
6857			if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
6858				BT_DBG("Busy, discarding expected seq %d",
6859				       control->txseq);
6860				break;
6861			}
6862
6863			chan->expected_tx_seq = __next_seq(chan,
6864							   control->txseq);
6865
6866			chan->buffer_seq = chan->expected_tx_seq;
6867			skb_in_use = true;
6868
6869			err = l2cap_reassemble_sdu(chan, skb, control);
6870			if (err)
6871				break;
6872
6873			if (control->final) {
6874				if (!test_and_clear_bit(CONN_REJ_ACT,
6875							&chan->conn_state)) {
6876					control->final = 0;
6877					l2cap_retransmit_all(chan, control);
6878					l2cap_ertm_send(chan);
6879				}
6880			}
6881
6882			if (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state))
6883				l2cap_send_ack(chan);
6884			break;
6885		case L2CAP_TXSEQ_UNEXPECTED:
6886			l2cap_pass_to_tx(chan, control);
6887
6888			/* Can't issue SREJ frames in the local busy state.
6889			 * Drop this frame, it will be seen as missing
6890			 * when local busy is exited.
6891			 */
6892			if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
6893				BT_DBG("Busy, discarding unexpected seq %d",
6894				       control->txseq);
6895				break;
6896			}
6897
6898			/* There was a gap in the sequence, so an SREJ
6899			 * must be sent for each missing frame.  The
6900			 * current frame is stored for later use.
6901			 */
6902			skb_queue_tail(&chan->srej_q, skb);
6903			skb_in_use = true;
6904			BT_DBG("Queued %p (queue len %d)", skb,
6905			       skb_queue_len(&chan->srej_q));
6906
6907			clear_bit(CONN_SREJ_ACT, &chan->conn_state);
6908			l2cap_seq_list_clear(&chan->srej_list);
6909			l2cap_send_srej(chan, control->txseq);
6910
6911			chan->rx_state = L2CAP_RX_STATE_SREJ_SENT;
6912			break;
6913		case L2CAP_TXSEQ_DUPLICATE:
6914			l2cap_pass_to_tx(chan, control);
6915			break;
6916		case L2CAP_TXSEQ_INVALID_IGNORE:
6917			break;
6918		case L2CAP_TXSEQ_INVALID:
6919		default:
6920			l2cap_send_disconn_req(chan, ECONNRESET);
6921			break;
6922		}
6923		break;
6924	case L2CAP_EV_RECV_RR:
6925		l2cap_pass_to_tx(chan, control);
6926		if (control->final) {
6927			clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6928
6929			if (!test_and_clear_bit(CONN_REJ_ACT, &chan->conn_state) &&
6930			    !__chan_is_moving(chan)) {
6931				control->final = 0;
6932				l2cap_retransmit_all(chan, control);
6933			}
6934
6935			l2cap_ertm_send(chan);
6936		} else if (control->poll) {
6937			l2cap_send_i_or_rr_or_rnr(chan);
6938		} else {
6939			if (test_and_clear_bit(CONN_REMOTE_BUSY,
6940					       &chan->conn_state) &&
6941			    chan->unacked_frames)
6942				__set_retrans_timer(chan);
6943
6944			l2cap_ertm_send(chan);
6945		}
6946		break;
6947	case L2CAP_EV_RECV_RNR:
6948		set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6949		l2cap_pass_to_tx(chan, control);
6950		if (control && control->poll) {
6951			set_bit(CONN_SEND_FBIT, &chan->conn_state);
6952			l2cap_send_rr_or_rnr(chan, 0);
6953		}
6954		__clear_retrans_timer(chan);
6955		l2cap_seq_list_clear(&chan->retrans_list);
6956		break;
6957	case L2CAP_EV_RECV_REJ:
6958		l2cap_handle_rej(chan, control);
6959		break;
6960	case L2CAP_EV_RECV_SREJ:
6961		l2cap_handle_srej(chan, control);
6962		break;
6963	default:
6964		break;
6965	}
6966
6967	if (skb && !skb_in_use) {
6968		BT_DBG("Freeing %p", skb);
6969		kfree_skb(skb);
6970	}
6971
6972	return err;
6973}
6974
6975static int l2cap_rx_state_srej_sent(struct l2cap_chan *chan,
6976				    struct l2cap_ctrl *control,
6977				    struct sk_buff *skb, u8 event)
6978{
6979	int err = 0;
6980	u16 txseq = control->txseq;
6981	bool skb_in_use = false;
6982
6983	BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
6984	       event);
6985
6986	switch (event) {
6987	case L2CAP_EV_RECV_IFRAME:
6988		switch (l2cap_classify_txseq(chan, txseq)) {
6989		case L2CAP_TXSEQ_EXPECTED:
6990			/* Keep frame for reassembly later */
6991			l2cap_pass_to_tx(chan, control);
6992			skb_queue_tail(&chan->srej_q, skb);
6993			skb_in_use = true;
6994			BT_DBG("Queued %p (queue len %d)", skb,
6995			       skb_queue_len(&chan->srej_q));
6996
6997			chan->expected_tx_seq = __next_seq(chan, txseq);
6998			break;
6999		case L2CAP_TXSEQ_EXPECTED_SREJ:
7000			l2cap_seq_list_pop(&chan->srej_list);
7001
7002			l2cap_pass_to_tx(chan, control);
7003			skb_queue_tail(&chan->srej_q, skb);
7004			skb_in_use = true;
7005			BT_DBG("Queued %p (queue len %d)", skb,
7006			       skb_queue_len(&chan->srej_q));
7007
7008			err = l2cap_rx_queued_iframes(chan);
7009			if (err)
7010				break;
7011
7012			break;
7013		case L2CAP_TXSEQ_UNEXPECTED:
7014			/* Got a frame that can't be reassembled yet.
7015			 * Save it for later, and send SREJs to cover
7016			 * the missing frames.
7017			 */
7018			skb_queue_tail(&chan->srej_q, skb);
7019			skb_in_use = true;
7020			BT_DBG("Queued %p (queue len %d)", skb,
7021			       skb_queue_len(&chan->srej_q));
7022
7023			l2cap_pass_to_tx(chan, control);
7024			l2cap_send_srej(chan, control->txseq);
7025			break;
7026		case L2CAP_TXSEQ_UNEXPECTED_SREJ:
7027			/* This frame was requested with an SREJ, but
7028			 * some expected retransmitted frames are
7029			 * missing.  Request retransmission of missing
7030			 * SREJ'd frames.
7031			 */
7032			skb_queue_tail(&chan->srej_q, skb);
7033			skb_in_use = true;
7034			BT_DBG("Queued %p (queue len %d)", skb,
7035			       skb_queue_len(&chan->srej_q));
7036
7037			l2cap_pass_to_tx(chan, control);
7038			l2cap_send_srej_list(chan, control->txseq);
7039			break;
7040		case L2CAP_TXSEQ_DUPLICATE_SREJ:
7041			/* We've already queued this frame.  Drop this copy. */
7042			l2cap_pass_to_tx(chan, control);
7043			break;
7044		case L2CAP_TXSEQ_DUPLICATE:
7045			/* Expecting a later sequence number, so this frame
7046			 * was already received.  Ignore it completely.
7047			 */
7048			break;
7049		case L2CAP_TXSEQ_INVALID_IGNORE:
7050			break;
7051		case L2CAP_TXSEQ_INVALID:
7052		default:
7053			l2cap_send_disconn_req(chan, ECONNRESET);
7054			break;
7055		}
7056		break;
7057	case L2CAP_EV_RECV_RR:
7058		l2cap_pass_to_tx(chan, control);
7059		if (control->final) {
7060			clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
7061
7062			if (!test_and_clear_bit(CONN_REJ_ACT,
7063						&chan->conn_state)) {
7064				control->final = 0;
7065				l2cap_retransmit_all(chan, control);
7066			}
7067
7068			l2cap_ertm_send(chan);
7069		} else if (control->poll) {
7070			if (test_and_clear_bit(CONN_REMOTE_BUSY,
7071					       &chan->conn_state) &&
7072			    chan->unacked_frames) {
7073				__set_retrans_timer(chan);
7074			}
7075
7076			set_bit(CONN_SEND_FBIT, &chan->conn_state);
7077			l2cap_send_srej_tail(chan);
7078		} else {
7079			if (test_and_clear_bit(CONN_REMOTE_BUSY,
7080					       &chan->conn_state) &&
7081			    chan->unacked_frames)
7082				__set_retrans_timer(chan);
7083
7084			l2cap_send_ack(chan);
7085		}
7086		break;
7087	case L2CAP_EV_RECV_RNR:
7088		set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
7089		l2cap_pass_to_tx(chan, control);
7090		if (control->poll) {
7091			l2cap_send_srej_tail(chan);
7092		} else {
7093			struct l2cap_ctrl rr_control;
7094			memset(&rr_control, 0, sizeof(rr_control));
7095			rr_control.sframe = 1;
7096			rr_control.super = L2CAP_SUPER_RR;
7097			rr_control.reqseq = chan->buffer_seq;
7098			l2cap_send_sframe(chan, &rr_control);
7099		}
7100
7101		break;
7102	case L2CAP_EV_RECV_REJ:
7103		l2cap_handle_rej(chan, control);
7104		break;
7105	case L2CAP_EV_RECV_SREJ:
7106		l2cap_handle_srej(chan, control);
7107		break;
7108	}
7109
7110	if (skb && !skb_in_use) {
7111		BT_DBG("Freeing %p", skb);
7112		kfree_skb(skb);
7113	}
7114
7115	return err;
7116}
7117
7118static int l2cap_finish_move(struct l2cap_chan *chan)
7119{
7120	BT_DBG("chan %p", chan);
7121
7122	chan->rx_state = L2CAP_RX_STATE_RECV;
7123
7124	if (chan->hs_hcon)
7125		chan->conn->mtu = chan->hs_hcon->hdev->block_mtu;
7126	else
7127		chan->conn->mtu = chan->conn->hcon->hdev->acl_mtu;
7128
7129	return l2cap_resegment(chan);
7130}
7131
7132static int l2cap_rx_state_wait_p(struct l2cap_chan *chan,
7133				 struct l2cap_ctrl *control,
7134				 struct sk_buff *skb, u8 event)
7135{
7136	int err;
7137
7138	BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
7139	       event);
7140
7141	if (!control->poll)
7142		return -EPROTO;
7143
7144	l2cap_process_reqseq(chan, control->reqseq);
7145
7146	if (!skb_queue_empty(&chan->tx_q))
7147		chan->tx_send_head = skb_peek(&chan->tx_q);
7148	else
7149		chan->tx_send_head = NULL;
7150
7151	/* Rewind next_tx_seq to the point expected
7152	 * by the receiver.
7153	 */
7154	chan->next_tx_seq = control->reqseq;
7155	chan->unacked_frames = 0;
7156
7157	err = l2cap_finish_move(chan);
7158	if (err)
7159		return err;
7160
7161	set_bit(CONN_SEND_FBIT, &chan->conn_state);
7162	l2cap_send_i_or_rr_or_rnr(chan);
7163
7164	if (event == L2CAP_EV_RECV_IFRAME)
7165		return -EPROTO;
7166
7167	return l2cap_rx_state_recv(chan, control, NULL, event);
7168}
7169
7170static int l2cap_rx_state_wait_f(struct l2cap_chan *chan,
7171				 struct l2cap_ctrl *control,
7172				 struct sk_buff *skb, u8 event)
7173{
7174	int err;
7175
7176	if (!control->final)
7177		return -EPROTO;
7178
7179	clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
7180
7181	chan->rx_state = L2CAP_RX_STATE_RECV;
7182	l2cap_process_reqseq(chan, control->reqseq);
7183
7184	if (!skb_queue_empty(&chan->tx_q))
7185		chan->tx_send_head = skb_peek(&chan->tx_q);
7186	else
7187		chan->tx_send_head = NULL;
7188
7189	/* Rewind next_tx_seq to the point expected
7190	 * by the receiver.
7191	 */
7192	chan->next_tx_seq = control->reqseq;
7193	chan->unacked_frames = 0;
7194
7195	if (chan->hs_hcon)
7196		chan->conn->mtu = chan->hs_hcon->hdev->block_mtu;
7197	else
7198		chan->conn->mtu = chan->conn->hcon->hdev->acl_mtu;
7199
7200	err = l2cap_resegment(chan);
7201
7202	if (!err)
7203		err = l2cap_rx_state_recv(chan, control, skb, event);
7204
7205	return err;
7206}
7207
7208static bool __valid_reqseq(struct l2cap_chan *chan, u16 reqseq)
7209{
7210	/* Make sure reqseq is for a packet that has been sent but not acked */
7211	u16 unacked;
7212
7213	unacked = __seq_offset(chan, chan->next_tx_seq, chan->expected_ack_seq);
7214	return __seq_offset(chan, chan->next_tx_seq, reqseq) <= unacked;
7215}
7216
7217static int l2cap_rx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
7218		    struct sk_buff *skb, u8 event)
7219{
7220	int err = 0;
7221
7222	BT_DBG("chan %p, control %p, skb %p, event %d, state %d", chan,
7223	       control, skb, event, chan->rx_state);
7224
7225	if (__valid_reqseq(chan, control->reqseq)) {
7226		switch (chan->rx_state) {
7227		case L2CAP_RX_STATE_RECV:
7228			err = l2cap_rx_state_recv(chan, control, skb, event);
7229			break;
7230		case L2CAP_RX_STATE_SREJ_SENT:
7231			err = l2cap_rx_state_srej_sent(chan, control, skb,
7232						       event);
7233			break;
7234		case L2CAP_RX_STATE_WAIT_P:
7235			err = l2cap_rx_state_wait_p(chan, control, skb, event);
7236			break;
7237		case L2CAP_RX_STATE_WAIT_F:
7238			err = l2cap_rx_state_wait_f(chan, control, skb, event);
7239			break;
7240		default:
7241			/* shut it down */
7242			break;
7243		}
7244	} else {
7245		BT_DBG("Invalid reqseq %d (next_tx_seq %d, expected_ack_seq %d",
7246		       control->reqseq, chan->next_tx_seq,
7247		       chan->expected_ack_seq);
7248		l2cap_send_disconn_req(chan, ECONNRESET);
7249	}
7250
7251	return err;
7252}
7253
7254static int l2cap_stream_rx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
7255			   struct sk_buff *skb)
7256{
7257	BT_DBG("chan %p, control %p, skb %p, state %d", chan, control, skb,
7258	       chan->rx_state);
7259
7260	if (l2cap_classify_txseq(chan, control->txseq) ==
7261	    L2CAP_TXSEQ_EXPECTED) {
7262		l2cap_pass_to_tx(chan, control);
7263
7264		BT_DBG("buffer_seq %u->%u", chan->buffer_seq,
7265		       __next_seq(chan, chan->buffer_seq));
7266
7267		chan->buffer_seq = __next_seq(chan, chan->buffer_seq);
7268
7269		l2cap_reassemble_sdu(chan, skb, control);
7270	} else {
7271		if (chan->sdu) {
7272			kfree_skb(chan->sdu);
7273			chan->sdu = NULL;
7274		}
7275		chan->sdu_last_frag = NULL;
7276		chan->sdu_len = 0;
7277
7278		if (skb) {
7279			BT_DBG("Freeing %p", skb);
7280			kfree_skb(skb);
7281		}
7282	}
7283
7284	chan->last_acked_seq = control->txseq;
7285	chan->expected_tx_seq = __next_seq(chan, control->txseq);
7286
7287	return 0;
7288}
7289
7290static int l2cap_data_rcv(struct l2cap_chan *chan, struct sk_buff *skb)
7291{
7292	struct l2cap_ctrl *control = &bt_cb(skb)->l2cap;
7293	u16 len;
7294	u8 event;
7295
7296	__unpack_control(chan, skb);
7297
7298	len = skb->len;
7299
7300	/*
7301	 * We can just drop the corrupted I-frame here.
7302	 * Receiver will miss it and start proper recovery
7303	 * procedures and ask for retransmission.
7304	 */
7305	if (l2cap_check_fcs(chan, skb))
7306		goto drop;
7307
7308	if (!control->sframe && control->sar == L2CAP_SAR_START)
7309		len -= L2CAP_SDULEN_SIZE;
7310
7311	if (chan->fcs == L2CAP_FCS_CRC16)
7312		len -= L2CAP_FCS_SIZE;
7313
7314	if (len > chan->mps) {
7315		l2cap_send_disconn_req(chan, ECONNRESET);
7316		goto drop;
7317	}
7318
7319	if (chan->ops->filter) {
7320		if (chan->ops->filter(chan, skb))
7321			goto drop;
7322	}
7323
7324	if (!control->sframe) {
7325		int err;
7326
7327		BT_DBG("iframe sar %d, reqseq %d, final %d, txseq %d",
7328		       control->sar, control->reqseq, control->final,
7329		       control->txseq);
7330
7331		/* Validate F-bit - F=0 always valid, F=1 only
7332		 * valid in TX WAIT_F
7333		 */
7334		if (control->final && chan->tx_state != L2CAP_TX_STATE_WAIT_F)
7335			goto drop;
7336
7337		if (chan->mode != L2CAP_MODE_STREAMING) {
7338			event = L2CAP_EV_RECV_IFRAME;
7339			err = l2cap_rx(chan, control, skb, event);
7340		} else {
7341			err = l2cap_stream_rx(chan, control, skb);
7342		}
7343
7344		if (err)
7345			l2cap_send_disconn_req(chan, ECONNRESET);
7346	} else {
7347		const u8 rx_func_to_event[4] = {
7348			L2CAP_EV_RECV_RR, L2CAP_EV_RECV_REJ,
7349			L2CAP_EV_RECV_RNR, L2CAP_EV_RECV_SREJ
7350		};
7351
7352		/* Only I-frames are expected in streaming mode */
7353		if (chan->mode == L2CAP_MODE_STREAMING)
7354			goto drop;
7355
7356		BT_DBG("sframe reqseq %d, final %d, poll %d, super %d",
7357		       control->reqseq, control->final, control->poll,
7358		       control->super);
7359
7360		if (len != 0) {
7361			BT_ERR("Trailing bytes: %d in sframe", len);
7362			l2cap_send_disconn_req(chan, ECONNRESET);
7363			goto drop;
7364		}
7365
7366		/* Validate F and P bits */
7367		if (control->final && (control->poll ||
7368				       chan->tx_state != L2CAP_TX_STATE_WAIT_F))
7369			goto drop;
7370
7371		event = rx_func_to_event[control->super];
7372		if (l2cap_rx(chan, control, skb, event))
7373			l2cap_send_disconn_req(chan, ECONNRESET);
7374	}
7375
7376	return 0;
7377
7378drop:
7379	kfree_skb(skb);
7380	return 0;
7381}
7382
7383static void l2cap_chan_le_send_credits(struct l2cap_chan *chan)
7384{
7385	struct l2cap_conn *conn = chan->conn;
7386	struct l2cap_le_credits pkt;
7387	u16 return_credits;
7388
7389	return_credits = (chan->imtu / chan->mps) + 1;
7390
7391	if (chan->rx_credits >= return_credits)
 
7392		return;
7393
7394	return_credits -= chan->rx_credits;
7395
7396	BT_DBG("chan %p returning %u credits to sender", chan, return_credits);
7397
7398	chan->rx_credits += return_credits;
7399
7400	pkt.cid     = cpu_to_le16(chan->scid);
7401	pkt.credits = cpu_to_le16(return_credits);
7402
7403	chan->ident = l2cap_get_ident(conn);
7404
7405	l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CREDITS, sizeof(pkt), &pkt);
7406}
7407
7408static int l2cap_ecred_recv(struct l2cap_chan *chan, struct sk_buff *skb)
7409{
7410	int err;
7411
7412	BT_DBG("SDU reassemble complete: chan %p skb->len %u", chan, skb->len);
7413
7414	/* Wait recv to confirm reception before updating the credits */
7415	err = chan->ops->recv(chan, skb);
7416
7417	/* Update credits whenever an SDU is received */
7418	l2cap_chan_le_send_credits(chan);
7419
7420	return err;
7421}
7422
7423static int l2cap_ecred_data_rcv(struct l2cap_chan *chan, struct sk_buff *skb)
7424{
7425	int err;
7426
7427	if (!chan->rx_credits) {
7428		BT_ERR("No credits to receive LE L2CAP data");
7429		l2cap_send_disconn_req(chan, ECONNRESET);
7430		return -ENOBUFS;
7431	}
7432
7433	if (chan->imtu < skb->len) {
7434		BT_ERR("Too big LE L2CAP PDU");
7435		return -ENOBUFS;
7436	}
7437
7438	chan->rx_credits--;
7439	BT_DBG("rx_credits %u -> %u", chan->rx_credits + 1, chan->rx_credits);
7440
7441	/* Update if remote had run out of credits, this should only happens
7442	 * if the remote is not using the entire MPS.
7443	 */
7444	if (!chan->rx_credits)
7445		l2cap_chan_le_send_credits(chan);
7446
7447	err = 0;
7448
7449	if (!chan->sdu) {
7450		u16 sdu_len;
7451
7452		sdu_len = get_unaligned_le16(skb->data);
7453		skb_pull(skb, L2CAP_SDULEN_SIZE);
7454
7455		BT_DBG("Start of new SDU. sdu_len %u skb->len %u imtu %u",
7456		       sdu_len, skb->len, chan->imtu);
7457
7458		if (sdu_len > chan->imtu) {
7459			BT_ERR("Too big LE L2CAP SDU length received");
7460			err = -EMSGSIZE;
7461			goto failed;
7462		}
7463
7464		if (skb->len > sdu_len) {
7465			BT_ERR("Too much LE L2CAP data received");
7466			err = -EINVAL;
7467			goto failed;
7468		}
7469
7470		if (skb->len == sdu_len)
7471			return l2cap_ecred_recv(chan, skb);
7472
7473		chan->sdu = skb;
7474		chan->sdu_len = sdu_len;
7475		chan->sdu_last_frag = skb;
7476
7477		/* Detect if remote is not able to use the selected MPS */
7478		if (skb->len + L2CAP_SDULEN_SIZE < chan->mps) {
7479			u16 mps_len = skb->len + L2CAP_SDULEN_SIZE;
7480
7481			/* Adjust the number of credits */
7482			BT_DBG("chan->mps %u -> %u", chan->mps, mps_len);
7483			chan->mps = mps_len;
7484			l2cap_chan_le_send_credits(chan);
7485		}
7486
7487		return 0;
7488	}
7489
7490	BT_DBG("SDU fragment. chan->sdu->len %u skb->len %u chan->sdu_len %u",
7491	       chan->sdu->len, skb->len, chan->sdu_len);
7492
7493	if (chan->sdu->len + skb->len > chan->sdu_len) {
7494		BT_ERR("Too much LE L2CAP data received");
7495		err = -EINVAL;
7496		goto failed;
7497	}
7498
7499	append_skb_frag(chan->sdu, skb, &chan->sdu_last_frag);
7500	skb = NULL;
7501
7502	if (chan->sdu->len == chan->sdu_len) {
7503		err = l2cap_ecred_recv(chan, chan->sdu);
7504		if (!err) {
7505			chan->sdu = NULL;
7506			chan->sdu_last_frag = NULL;
7507			chan->sdu_len = 0;
7508		}
7509	}
7510
7511failed:
7512	if (err) {
7513		kfree_skb(skb);
7514		kfree_skb(chan->sdu);
7515		chan->sdu = NULL;
7516		chan->sdu_last_frag = NULL;
7517		chan->sdu_len = 0;
7518	}
7519
7520	/* We can't return an error here since we took care of the skb
7521	 * freeing internally. An error return would cause the caller to
7522	 * do a double-free of the skb.
7523	 */
7524	return 0;
7525}
7526
7527static void l2cap_data_channel(struct l2cap_conn *conn, u16 cid,
7528			       struct sk_buff *skb)
7529{
7530	struct l2cap_chan *chan;
7531
7532	chan = l2cap_get_chan_by_scid(conn, cid);
7533	if (!chan) {
7534		if (cid == L2CAP_CID_A2MP) {
7535			chan = a2mp_channel_create(conn, skb);
7536			if (!chan) {
7537				kfree_skb(skb);
7538				return;
7539			}
7540
7541			l2cap_chan_lock(chan);
7542		} else {
7543			BT_DBG("unknown cid 0x%4.4x", cid);
7544			/* Drop packet and return */
7545			kfree_skb(skb);
7546			return;
7547		}
7548	}
7549
7550	BT_DBG("chan %p, len %d", chan, skb->len);
7551
7552	/* If we receive data on a fixed channel before the info req/rsp
7553	 * procedure is done simply assume that the channel is supported
7554	 * and mark it as ready.
7555	 */
7556	if (chan->chan_type == L2CAP_CHAN_FIXED)
7557		l2cap_chan_ready(chan);
7558
7559	if (chan->state != BT_CONNECTED)
7560		goto drop;
7561
7562	switch (chan->mode) {
7563	case L2CAP_MODE_LE_FLOWCTL:
7564	case L2CAP_MODE_EXT_FLOWCTL:
7565		if (l2cap_ecred_data_rcv(chan, skb) < 0)
7566			goto drop;
7567
7568		goto done;
7569
7570	case L2CAP_MODE_BASIC:
7571		/* If socket recv buffers overflows we drop data here
7572		 * which is *bad* because L2CAP has to be reliable.
7573		 * But we don't have any other choice. L2CAP doesn't
7574		 * provide flow control mechanism. */
7575
7576		if (chan->imtu < skb->len) {
7577			BT_ERR("Dropping L2CAP data: receive buffer overflow");
7578			goto drop;
7579		}
7580
7581		if (!chan->ops->recv(chan, skb))
7582			goto done;
7583		break;
7584
7585	case L2CAP_MODE_ERTM:
7586	case L2CAP_MODE_STREAMING:
7587		l2cap_data_rcv(chan, skb);
7588		goto done;
7589
7590	default:
7591		BT_DBG("chan %p: bad mode 0x%2.2x", chan, chan->mode);
7592		break;
7593	}
7594
7595drop:
7596	kfree_skb(skb);
7597
7598done:
7599	l2cap_chan_unlock(chan);
7600}
7601
7602static void l2cap_conless_channel(struct l2cap_conn *conn, __le16 psm,
7603				  struct sk_buff *skb)
7604{
7605	struct hci_conn *hcon = conn->hcon;
7606	struct l2cap_chan *chan;
7607
7608	if (hcon->type != ACL_LINK)
7609		goto free_skb;
7610
7611	chan = l2cap_global_chan_by_psm(0, psm, &hcon->src, &hcon->dst,
7612					ACL_LINK);
7613	if (!chan)
7614		goto free_skb;
7615
7616	BT_DBG("chan %p, len %d", chan, skb->len);
7617
7618	if (chan->state != BT_BOUND && chan->state != BT_CONNECTED)
7619		goto drop;
7620
7621	if (chan->imtu < skb->len)
7622		goto drop;
7623
7624	/* Store remote BD_ADDR and PSM for msg_name */
7625	bacpy(&bt_cb(skb)->l2cap.bdaddr, &hcon->dst);
7626	bt_cb(skb)->l2cap.psm = psm;
7627
7628	if (!chan->ops->recv(chan, skb)) {
7629		l2cap_chan_put(chan);
7630		return;
7631	}
7632
7633drop:
7634	l2cap_chan_put(chan);
7635free_skb:
7636	kfree_skb(skb);
7637}
7638
7639static void l2cap_recv_frame(struct l2cap_conn *conn, struct sk_buff *skb)
7640{
7641	struct l2cap_hdr *lh = (void *) skb->data;
7642	struct hci_conn *hcon = conn->hcon;
7643	u16 cid, len;
7644	__le16 psm;
7645
7646	if (hcon->state != BT_CONNECTED) {
7647		BT_DBG("queueing pending rx skb");
7648		skb_queue_tail(&conn->pending_rx, skb);
7649		return;
7650	}
7651
7652	skb_pull(skb, L2CAP_HDR_SIZE);
7653	cid = __le16_to_cpu(lh->cid);
7654	len = __le16_to_cpu(lh->len);
7655
7656	if (len != skb->len) {
7657		kfree_skb(skb);
7658		return;
7659	}
7660
7661	/* Since we can't actively block incoming LE connections we must
7662	 * at least ensure that we ignore incoming data from them.
7663	 */
7664	if (hcon->type == LE_LINK &&
7665	    hci_bdaddr_list_lookup(&hcon->hdev->reject_list, &hcon->dst,
7666				   bdaddr_dst_type(hcon))) {
7667		kfree_skb(skb);
7668		return;
7669	}
7670
7671	BT_DBG("len %d, cid 0x%4.4x", len, cid);
7672
7673	switch (cid) {
7674	case L2CAP_CID_SIGNALING:
7675		l2cap_sig_channel(conn, skb);
7676		break;
7677
7678	case L2CAP_CID_CONN_LESS:
7679		psm = get_unaligned((__le16 *) skb->data);
7680		skb_pull(skb, L2CAP_PSMLEN_SIZE);
7681		l2cap_conless_channel(conn, psm, skb);
7682		break;
7683
7684	case L2CAP_CID_LE_SIGNALING:
7685		l2cap_le_sig_channel(conn, skb);
7686		break;
7687
7688	default:
7689		l2cap_data_channel(conn, cid, skb);
7690		break;
7691	}
7692}
7693
7694static void process_pending_rx(struct work_struct *work)
7695{
7696	struct l2cap_conn *conn = container_of(work, struct l2cap_conn,
7697					       pending_rx_work);
7698	struct sk_buff *skb;
7699
7700	BT_DBG("");
7701
7702	while ((skb = skb_dequeue(&conn->pending_rx)))
7703		l2cap_recv_frame(conn, skb);
7704}
7705
7706static struct l2cap_conn *l2cap_conn_add(struct hci_conn *hcon)
7707{
7708	struct l2cap_conn *conn = hcon->l2cap_data;
7709	struct hci_chan *hchan;
7710
7711	if (conn)
7712		return conn;
7713
7714	hchan = hci_chan_create(hcon);
7715	if (!hchan)
7716		return NULL;
7717
7718	conn = kzalloc(sizeof(*conn), GFP_KERNEL);
7719	if (!conn) {
7720		hci_chan_del(hchan);
7721		return NULL;
7722	}
7723
7724	kref_init(&conn->ref);
7725	hcon->l2cap_data = conn;
7726	conn->hcon = hci_conn_get(hcon);
7727	conn->hchan = hchan;
7728
7729	BT_DBG("hcon %p conn %p hchan %p", hcon, conn, hchan);
7730
7731	switch (hcon->type) {
7732	case LE_LINK:
7733		if (hcon->hdev->le_mtu) {
7734			conn->mtu = hcon->hdev->le_mtu;
7735			break;
7736		}
7737		fallthrough;
7738	default:
7739		conn->mtu = hcon->hdev->acl_mtu;
7740		break;
7741	}
7742
7743	conn->feat_mask = 0;
7744
7745	conn->local_fixed_chan = L2CAP_FC_SIG_BREDR | L2CAP_FC_CONNLESS;
7746
7747	if (hcon->type == ACL_LINK &&
7748	    hci_dev_test_flag(hcon->hdev, HCI_HS_ENABLED))
7749		conn->local_fixed_chan |= L2CAP_FC_A2MP;
7750
7751	if (hci_dev_test_flag(hcon->hdev, HCI_LE_ENABLED) &&
7752	    (bredr_sc_enabled(hcon->hdev) ||
7753	     hci_dev_test_flag(hcon->hdev, HCI_FORCE_BREDR_SMP)))
7754		conn->local_fixed_chan |= L2CAP_FC_SMP_BREDR;
7755
7756	mutex_init(&conn->ident_lock);
7757	mutex_init(&conn->chan_lock);
7758
7759	INIT_LIST_HEAD(&conn->chan_l);
7760	INIT_LIST_HEAD(&conn->users);
7761
7762	INIT_DELAYED_WORK(&conn->info_timer, l2cap_info_timeout);
7763
7764	skb_queue_head_init(&conn->pending_rx);
7765	INIT_WORK(&conn->pending_rx_work, process_pending_rx);
7766	INIT_WORK(&conn->id_addr_update_work, l2cap_conn_update_id_addr);
7767
7768	conn->disc_reason = HCI_ERROR_REMOTE_USER_TERM;
7769
7770	return conn;
7771}
7772
7773static bool is_valid_psm(u16 psm, u8 dst_type)
7774{
7775	if (!psm)
7776		return false;
7777
7778	if (bdaddr_type_is_le(dst_type))
7779		return (psm <= 0x00ff);
7780
7781	/* PSM must be odd and lsb of upper byte must be 0 */
7782	return ((psm & 0x0101) == 0x0001);
7783}
7784
7785struct l2cap_chan_data {
7786	struct l2cap_chan *chan;
7787	struct pid *pid;
7788	int count;
7789};
7790
7791static void l2cap_chan_by_pid(struct l2cap_chan *chan, void *data)
7792{
7793	struct l2cap_chan_data *d = data;
7794	struct pid *pid;
7795
7796	if (chan == d->chan)
7797		return;
7798
7799	if (!test_bit(FLAG_DEFER_SETUP, &chan->flags))
7800		return;
7801
7802	pid = chan->ops->get_peer_pid(chan);
7803
7804	/* Only count deferred channels with the same PID/PSM */
7805	if (d->pid != pid || chan->psm != d->chan->psm || chan->ident ||
7806	    chan->mode != L2CAP_MODE_EXT_FLOWCTL || chan->state != BT_CONNECT)
7807		return;
7808
7809	d->count++;
7810}
7811
7812int l2cap_chan_connect(struct l2cap_chan *chan, __le16 psm, u16 cid,
7813		       bdaddr_t *dst, u8 dst_type)
7814{
7815	struct l2cap_conn *conn;
7816	struct hci_conn *hcon;
7817	struct hci_dev *hdev;
7818	int err;
7819
7820	BT_DBG("%pMR -> %pMR (type %u) psm 0x%4.4x mode 0x%2.2x", &chan->src,
7821	       dst, dst_type, __le16_to_cpu(psm), chan->mode);
7822
7823	hdev = hci_get_route(dst, &chan->src, chan->src_type);
7824	if (!hdev)
7825		return -EHOSTUNREACH;
7826
7827	hci_dev_lock(hdev);
7828
7829	if (!is_valid_psm(__le16_to_cpu(psm), dst_type) && !cid &&
7830	    chan->chan_type != L2CAP_CHAN_RAW) {
7831		err = -EINVAL;
7832		goto done;
7833	}
7834
7835	if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED && !psm) {
7836		err = -EINVAL;
7837		goto done;
7838	}
7839
7840	if (chan->chan_type == L2CAP_CHAN_FIXED && !cid) {
7841		err = -EINVAL;
7842		goto done;
7843	}
7844
7845	switch (chan->mode) {
7846	case L2CAP_MODE_BASIC:
7847		break;
7848	case L2CAP_MODE_LE_FLOWCTL:
7849		break;
7850	case L2CAP_MODE_EXT_FLOWCTL:
7851		if (!enable_ecred) {
7852			err = -EOPNOTSUPP;
7853			goto done;
7854		}
7855		break;
7856	case L2CAP_MODE_ERTM:
7857	case L2CAP_MODE_STREAMING:
7858		if (!disable_ertm)
7859			break;
7860		fallthrough;
7861	default:
7862		err = -EOPNOTSUPP;
7863		goto done;
7864	}
7865
7866	switch (chan->state) {
7867	case BT_CONNECT:
7868	case BT_CONNECT2:
7869	case BT_CONFIG:
7870		/* Already connecting */
7871		err = 0;
7872		goto done;
7873
7874	case BT_CONNECTED:
7875		/* Already connected */
7876		err = -EISCONN;
7877		goto done;
7878
7879	case BT_OPEN:
7880	case BT_BOUND:
7881		/* Can connect */
7882		break;
7883
7884	default:
7885		err = -EBADFD;
7886		goto done;
7887	}
7888
7889	/* Set destination address and psm */
7890	bacpy(&chan->dst, dst);
7891	chan->dst_type = dst_type;
7892
7893	chan->psm = psm;
7894	chan->dcid = cid;
7895
7896	if (bdaddr_type_is_le(dst_type)) {
7897		/* Convert from L2CAP channel address type to HCI address type
7898		 */
7899		if (dst_type == BDADDR_LE_PUBLIC)
7900			dst_type = ADDR_LE_DEV_PUBLIC;
7901		else
7902			dst_type = ADDR_LE_DEV_RANDOM;
7903
7904		if (hci_dev_test_flag(hdev, HCI_ADVERTISING))
7905			hcon = hci_connect_le(hdev, dst, dst_type,
7906					      chan->sec_level,
7907					      HCI_LE_CONN_TIMEOUT,
7908					      HCI_ROLE_SLAVE, NULL);
7909		else
7910			hcon = hci_connect_le_scan(hdev, dst, dst_type,
7911						   chan->sec_level,
7912						   HCI_LE_CONN_TIMEOUT,
7913						   CONN_REASON_L2CAP_CHAN);
7914
7915	} else {
7916		u8 auth_type = l2cap_get_auth_type(chan);
7917		hcon = hci_connect_acl(hdev, dst, chan->sec_level, auth_type,
7918				       CONN_REASON_L2CAP_CHAN);
7919	}
7920
7921	if (IS_ERR(hcon)) {
7922		err = PTR_ERR(hcon);
7923		goto done;
7924	}
7925
7926	conn = l2cap_conn_add(hcon);
7927	if (!conn) {
7928		hci_conn_drop(hcon);
7929		err = -ENOMEM;
7930		goto done;
7931	}
7932
7933	if (chan->mode == L2CAP_MODE_EXT_FLOWCTL) {
7934		struct l2cap_chan_data data;
7935
7936		data.chan = chan;
7937		data.pid = chan->ops->get_peer_pid(chan);
7938		data.count = 1;
7939
7940		l2cap_chan_list(conn, l2cap_chan_by_pid, &data);
7941
7942		/* Check if there isn't too many channels being connected */
7943		if (data.count > L2CAP_ECRED_CONN_SCID_MAX) {
7944			hci_conn_drop(hcon);
7945			err = -EPROTO;
7946			goto done;
7947		}
7948	}
7949
7950	mutex_lock(&conn->chan_lock);
7951	l2cap_chan_lock(chan);
7952
7953	if (cid && __l2cap_get_chan_by_dcid(conn, cid)) {
7954		hci_conn_drop(hcon);
7955		err = -EBUSY;
7956		goto chan_unlock;
7957	}
7958
7959	/* Update source addr of the socket */
7960	bacpy(&chan->src, &hcon->src);
7961	chan->src_type = bdaddr_src_type(hcon);
7962
7963	__l2cap_chan_add(conn, chan);
7964
7965	/* l2cap_chan_add takes its own ref so we can drop this one */
7966	hci_conn_drop(hcon);
7967
7968	l2cap_state_change(chan, BT_CONNECT);
7969	__set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
7970
7971	/* Release chan->sport so that it can be reused by other
7972	 * sockets (as it's only used for listening sockets).
7973	 */
7974	write_lock(&chan_list_lock);
7975	chan->sport = 0;
7976	write_unlock(&chan_list_lock);
7977
7978	if (hcon->state == BT_CONNECTED) {
7979		if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
7980			__clear_chan_timer(chan);
7981			if (l2cap_chan_check_security(chan, true))
7982				l2cap_state_change(chan, BT_CONNECTED);
7983		} else
7984			l2cap_do_start(chan);
7985	}
7986
7987	err = 0;
7988
7989chan_unlock:
7990	l2cap_chan_unlock(chan);
7991	mutex_unlock(&conn->chan_lock);
7992done:
7993	hci_dev_unlock(hdev);
7994	hci_dev_put(hdev);
7995	return err;
7996}
7997EXPORT_SYMBOL_GPL(l2cap_chan_connect);
7998
7999static void l2cap_ecred_reconfigure(struct l2cap_chan *chan)
8000{
8001	struct l2cap_conn *conn = chan->conn;
8002	struct {
8003		struct l2cap_ecred_reconf_req req;
8004		__le16 scid;
8005	} pdu;
8006
8007	pdu.req.mtu = cpu_to_le16(chan->imtu);
8008	pdu.req.mps = cpu_to_le16(chan->mps);
8009	pdu.scid    = cpu_to_le16(chan->scid);
8010
8011	chan->ident = l2cap_get_ident(conn);
8012
8013	l2cap_send_cmd(conn, chan->ident, L2CAP_ECRED_RECONF_REQ,
8014		       sizeof(pdu), &pdu);
8015}
8016
8017int l2cap_chan_reconfigure(struct l2cap_chan *chan, __u16 mtu)
8018{
8019	if (chan->imtu > mtu)
8020		return -EINVAL;
8021
8022	BT_DBG("chan %p mtu 0x%4.4x", chan, mtu);
8023
8024	chan->imtu = mtu;
8025
8026	l2cap_ecred_reconfigure(chan);
8027
8028	return 0;
8029}
8030
8031/* ---- L2CAP interface with lower layer (HCI) ---- */
8032
8033int l2cap_connect_ind(struct hci_dev *hdev, bdaddr_t *bdaddr)
8034{
8035	int exact = 0, lm1 = 0, lm2 = 0;
8036	struct l2cap_chan *c;
8037
8038	BT_DBG("hdev %s, bdaddr %pMR", hdev->name, bdaddr);
8039
8040	/* Find listening sockets and check their link_mode */
8041	read_lock(&chan_list_lock);
8042	list_for_each_entry(c, &chan_list, global_l) {
8043		if (c->state != BT_LISTEN)
8044			continue;
8045
8046		if (!bacmp(&c->src, &hdev->bdaddr)) {
8047			lm1 |= HCI_LM_ACCEPT;
8048			if (test_bit(FLAG_ROLE_SWITCH, &c->flags))
8049				lm1 |= HCI_LM_MASTER;
8050			exact++;
8051		} else if (!bacmp(&c->src, BDADDR_ANY)) {
8052			lm2 |= HCI_LM_ACCEPT;
8053			if (test_bit(FLAG_ROLE_SWITCH, &c->flags))
8054				lm2 |= HCI_LM_MASTER;
8055		}
8056	}
8057	read_unlock(&chan_list_lock);
8058
8059	return exact ? lm1 : lm2;
8060}
8061
8062/* Find the next fixed channel in BT_LISTEN state, continue iteration
8063 * from an existing channel in the list or from the beginning of the
8064 * global list (by passing NULL as first parameter).
8065 */
8066static struct l2cap_chan *l2cap_global_fixed_chan(struct l2cap_chan *c,
8067						  struct hci_conn *hcon)
8068{
8069	u8 src_type = bdaddr_src_type(hcon);
8070
8071	read_lock(&chan_list_lock);
8072
8073	if (c)
8074		c = list_next_entry(c, global_l);
8075	else
8076		c = list_entry(chan_list.next, typeof(*c), global_l);
8077
8078	list_for_each_entry_from(c, &chan_list, global_l) {
8079		if (c->chan_type != L2CAP_CHAN_FIXED)
8080			continue;
8081		if (c->state != BT_LISTEN)
8082			continue;
8083		if (bacmp(&c->src, &hcon->src) && bacmp(&c->src, BDADDR_ANY))
8084			continue;
8085		if (src_type != c->src_type)
8086			continue;
8087
8088		l2cap_chan_hold(c);
8089		read_unlock(&chan_list_lock);
8090		return c;
8091	}
8092
8093	read_unlock(&chan_list_lock);
8094
8095	return NULL;
8096}
8097
8098static void l2cap_connect_cfm(struct hci_conn *hcon, u8 status)
8099{
8100	struct hci_dev *hdev = hcon->hdev;
8101	struct l2cap_conn *conn;
8102	struct l2cap_chan *pchan;
8103	u8 dst_type;
8104
8105	if (hcon->type != ACL_LINK && hcon->type != LE_LINK)
8106		return;
8107
8108	BT_DBG("hcon %p bdaddr %pMR status %d", hcon, &hcon->dst, status);
8109
8110	if (status) {
8111		l2cap_conn_del(hcon, bt_to_errno(status));
8112		return;
8113	}
8114
8115	conn = l2cap_conn_add(hcon);
8116	if (!conn)
8117		return;
8118
8119	dst_type = bdaddr_dst_type(hcon);
8120
8121	/* If device is blocked, do not create channels for it */
8122	if (hci_bdaddr_list_lookup(&hdev->reject_list, &hcon->dst, dst_type))
8123		return;
8124
8125	/* Find fixed channels and notify them of the new connection. We
8126	 * use multiple individual lookups, continuing each time where
8127	 * we left off, because the list lock would prevent calling the
8128	 * potentially sleeping l2cap_chan_lock() function.
8129	 */
8130	pchan = l2cap_global_fixed_chan(NULL, hcon);
8131	while (pchan) {
8132		struct l2cap_chan *chan, *next;
8133
8134		/* Client fixed channels should override server ones */
8135		if (__l2cap_get_chan_by_dcid(conn, pchan->scid))
8136			goto next;
8137
8138		l2cap_chan_lock(pchan);
8139		chan = pchan->ops->new_connection(pchan);
8140		if (chan) {
8141			bacpy(&chan->src, &hcon->src);
8142			bacpy(&chan->dst, &hcon->dst);
8143			chan->src_type = bdaddr_src_type(hcon);
8144			chan->dst_type = dst_type;
8145
8146			__l2cap_chan_add(conn, chan);
8147		}
8148
8149		l2cap_chan_unlock(pchan);
8150next:
8151		next = l2cap_global_fixed_chan(pchan, hcon);
8152		l2cap_chan_put(pchan);
8153		pchan = next;
8154	}
8155
8156	l2cap_conn_ready(conn);
8157}
8158
8159int l2cap_disconn_ind(struct hci_conn *hcon)
8160{
8161	struct l2cap_conn *conn = hcon->l2cap_data;
8162
8163	BT_DBG("hcon %p", hcon);
8164
8165	if (!conn)
8166		return HCI_ERROR_REMOTE_USER_TERM;
8167	return conn->disc_reason;
8168}
8169
8170static void l2cap_disconn_cfm(struct hci_conn *hcon, u8 reason)
8171{
8172	if (hcon->type != ACL_LINK && hcon->type != LE_LINK)
8173		return;
8174
8175	BT_DBG("hcon %p reason %d", hcon, reason);
8176
8177	l2cap_conn_del(hcon, bt_to_errno(reason));
8178}
8179
8180static inline void l2cap_check_encryption(struct l2cap_chan *chan, u8 encrypt)
8181{
8182	if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED)
8183		return;
8184
8185	if (encrypt == 0x00) {
8186		if (chan->sec_level == BT_SECURITY_MEDIUM) {
8187			__set_chan_timer(chan, L2CAP_ENC_TIMEOUT);
8188		} else if (chan->sec_level == BT_SECURITY_HIGH ||
8189			   chan->sec_level == BT_SECURITY_FIPS)
8190			l2cap_chan_close(chan, ECONNREFUSED);
8191	} else {
8192		if (chan->sec_level == BT_SECURITY_MEDIUM)
8193			__clear_chan_timer(chan);
8194	}
8195}
8196
8197static void l2cap_security_cfm(struct hci_conn *hcon, u8 status, u8 encrypt)
8198{
8199	struct l2cap_conn *conn = hcon->l2cap_data;
8200	struct l2cap_chan *chan;
8201
8202	if (!conn)
8203		return;
8204
8205	BT_DBG("conn %p status 0x%2.2x encrypt %u", conn, status, encrypt);
8206
8207	mutex_lock(&conn->chan_lock);
8208
8209	list_for_each_entry(chan, &conn->chan_l, list) {
8210		l2cap_chan_lock(chan);
8211
8212		BT_DBG("chan %p scid 0x%4.4x state %s", chan, chan->scid,
8213		       state_to_string(chan->state));
8214
8215		if (chan->scid == L2CAP_CID_A2MP) {
8216			l2cap_chan_unlock(chan);
8217			continue;
8218		}
8219
8220		if (!status && encrypt)
8221			chan->sec_level = hcon->sec_level;
8222
8223		if (!__l2cap_no_conn_pending(chan)) {
8224			l2cap_chan_unlock(chan);
8225			continue;
8226		}
8227
8228		if (!status && (chan->state == BT_CONNECTED ||
8229				chan->state == BT_CONFIG)) {
8230			chan->ops->resume(chan);
8231			l2cap_check_encryption(chan, encrypt);
8232			l2cap_chan_unlock(chan);
8233			continue;
8234		}
8235
8236		if (chan->state == BT_CONNECT) {
8237			if (!status && l2cap_check_enc_key_size(hcon))
8238				l2cap_start_connection(chan);
8239			else
8240				__set_chan_timer(chan, L2CAP_DISC_TIMEOUT);
8241		} else if (chan->state == BT_CONNECT2 &&
8242			   !(chan->mode == L2CAP_MODE_EXT_FLOWCTL ||
8243			     chan->mode == L2CAP_MODE_LE_FLOWCTL)) {
8244			struct l2cap_conn_rsp rsp;
8245			__u16 res, stat;
8246
8247			if (!status && l2cap_check_enc_key_size(hcon)) {
8248				if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
8249					res = L2CAP_CR_PEND;
8250					stat = L2CAP_CS_AUTHOR_PEND;
8251					chan->ops->defer(chan);
8252				} else {
8253					l2cap_state_change(chan, BT_CONFIG);
8254					res = L2CAP_CR_SUCCESS;
8255					stat = L2CAP_CS_NO_INFO;
8256				}
8257			} else {
8258				l2cap_state_change(chan, BT_DISCONN);
8259				__set_chan_timer(chan, L2CAP_DISC_TIMEOUT);
8260				res = L2CAP_CR_SEC_BLOCK;
8261				stat = L2CAP_CS_NO_INFO;
8262			}
8263
8264			rsp.scid   = cpu_to_le16(chan->dcid);
8265			rsp.dcid   = cpu_to_le16(chan->scid);
8266			rsp.result = cpu_to_le16(res);
8267			rsp.status = cpu_to_le16(stat);
8268			l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP,
8269				       sizeof(rsp), &rsp);
8270
8271			if (!test_bit(CONF_REQ_SENT, &chan->conf_state) &&
8272			    res == L2CAP_CR_SUCCESS) {
8273				char buf[128];
8274				set_bit(CONF_REQ_SENT, &chan->conf_state);
8275				l2cap_send_cmd(conn, l2cap_get_ident(conn),
8276					       L2CAP_CONF_REQ,
8277					       l2cap_build_conf_req(chan, buf, sizeof(buf)),
8278					       buf);
8279				chan->num_conf_req++;
8280			}
8281		}
8282
8283		l2cap_chan_unlock(chan);
8284	}
8285
8286	mutex_unlock(&conn->chan_lock);
8287}
8288
8289/* Append fragment into frame respecting the maximum len of rx_skb */
8290static int l2cap_recv_frag(struct l2cap_conn *conn, struct sk_buff *skb,
8291			   u16 len)
8292{
8293	if (!conn->rx_skb) {
8294		/* Allocate skb for the complete frame (with header) */
8295		conn->rx_skb = bt_skb_alloc(len, GFP_KERNEL);
8296		if (!conn->rx_skb)
8297			return -ENOMEM;
8298		/* Init rx_len */
8299		conn->rx_len = len;
8300	}
8301
8302	/* Copy as much as the rx_skb can hold */
8303	len = min_t(u16, len, skb->len);
8304	skb_copy_from_linear_data(skb, skb_put(conn->rx_skb, len), len);
8305	skb_pull(skb, len);
8306	conn->rx_len -= len;
8307
8308	return len;
8309}
8310
8311static int l2cap_recv_len(struct l2cap_conn *conn, struct sk_buff *skb)
8312{
8313	struct sk_buff *rx_skb;
8314	int len;
8315
8316	/* Append just enough to complete the header */
8317	len = l2cap_recv_frag(conn, skb, L2CAP_LEN_SIZE - conn->rx_skb->len);
8318
8319	/* If header could not be read just continue */
8320	if (len < 0 || conn->rx_skb->len < L2CAP_LEN_SIZE)
8321		return len;
8322
8323	rx_skb = conn->rx_skb;
8324	len = get_unaligned_le16(rx_skb->data);
8325
8326	/* Check if rx_skb has enough space to received all fragments */
8327	if (len + (L2CAP_HDR_SIZE - L2CAP_LEN_SIZE) <= skb_tailroom(rx_skb)) {
8328		/* Update expected len */
8329		conn->rx_len = len + (L2CAP_HDR_SIZE - L2CAP_LEN_SIZE);
8330		return L2CAP_LEN_SIZE;
8331	}
8332
8333	/* Reset conn->rx_skb since it will need to be reallocated in order to
8334	 * fit all fragments.
8335	 */
8336	conn->rx_skb = NULL;
8337
8338	/* Reallocates rx_skb using the exact expected length */
8339	len = l2cap_recv_frag(conn, rx_skb,
8340			      len + (L2CAP_HDR_SIZE - L2CAP_LEN_SIZE));
8341	kfree_skb(rx_skb);
8342
8343	return len;
8344}
8345
8346static void l2cap_recv_reset(struct l2cap_conn *conn)
8347{
8348	kfree_skb(conn->rx_skb);
8349	conn->rx_skb = NULL;
8350	conn->rx_len = 0;
8351}
8352
8353void l2cap_recv_acldata(struct hci_conn *hcon, struct sk_buff *skb, u16 flags)
8354{
8355	struct l2cap_conn *conn = hcon->l2cap_data;
 
8356	int len;
8357
8358	/* For AMP controller do not create l2cap conn */
8359	if (!conn && hcon->hdev->dev_type != HCI_PRIMARY)
8360		goto drop;
8361
8362	if (!conn)
8363		conn = l2cap_conn_add(hcon);
8364
8365	if (!conn)
8366		goto drop;
8367
8368	BT_DBG("conn %p len %u flags 0x%x", conn, skb->len, flags);
8369
8370	switch (flags) {
8371	case ACL_START:
8372	case ACL_START_NO_FLUSH:
8373	case ACL_COMPLETE:
8374		if (conn->rx_skb) {
8375			BT_ERR("Unexpected start frame (len %d)", skb->len);
8376			l2cap_recv_reset(conn);
 
 
8377			l2cap_conn_unreliable(conn, ECOMM);
8378		}
8379
8380		/* Start fragment may not contain the L2CAP length so just
8381		 * copy the initial byte when that happens and use conn->mtu as
8382		 * expected length.
8383		 */
8384		if (skb->len < L2CAP_LEN_SIZE) {
8385			if (l2cap_recv_frag(conn, skb, conn->mtu) < 0)
8386				goto drop;
8387			return;
8388		}
8389
8390		len = get_unaligned_le16(skb->data) + L2CAP_HDR_SIZE;
 
8391
8392		if (len == skb->len) {
8393			/* Complete frame received */
8394			l2cap_recv_frame(conn, skb);
8395			return;
8396		}
8397
8398		BT_DBG("Start: total len %d, frag len %u", len, skb->len);
8399
8400		if (skb->len > len) {
8401			BT_ERR("Frame is too long (len %u, expected len %d)",
8402			       skb->len, len);
8403			l2cap_conn_unreliable(conn, ECOMM);
8404			goto drop;
8405		}
8406
8407		/* Append fragment into frame (with header) */
8408		if (l2cap_recv_frag(conn, skb, len) < 0)
 
8409			goto drop;
8410
 
 
 
8411		break;
8412
8413	case ACL_CONT:
8414		BT_DBG("Cont: frag len %u (expecting %u)", skb->len, conn->rx_len);
8415
8416		if (!conn->rx_skb) {
8417			BT_ERR("Unexpected continuation frame (len %d)", skb->len);
8418			l2cap_conn_unreliable(conn, ECOMM);
8419			goto drop;
8420		}
8421
8422		/* Complete the L2CAP length if it has not been read */
8423		if (conn->rx_skb->len < L2CAP_LEN_SIZE) {
8424			if (l2cap_recv_len(conn, skb) < 0) {
8425				l2cap_conn_unreliable(conn, ECOMM);
8426				goto drop;
8427			}
8428
8429			/* Header still could not be read just continue */
8430			if (conn->rx_skb->len < L2CAP_LEN_SIZE)
8431				return;
8432		}
8433
8434		if (skb->len > conn->rx_len) {
8435			BT_ERR("Fragment is too long (len %u, expected %u)",
8436			       skb->len, conn->rx_len);
8437			l2cap_recv_reset(conn);
 
 
8438			l2cap_conn_unreliable(conn, ECOMM);
8439			goto drop;
8440		}
8441
8442		/* Append fragment into frame (with header) */
8443		l2cap_recv_frag(conn, skb, skb->len);
 
8444
8445		if (!conn->rx_len) {
8446			/* Complete frame received. l2cap_recv_frame
8447			 * takes ownership of the skb so set the global
8448			 * rx_skb pointer to NULL first.
8449			 */
8450			struct sk_buff *rx_skb = conn->rx_skb;
8451			conn->rx_skb = NULL;
8452			l2cap_recv_frame(conn, rx_skb);
8453		}
8454		break;
8455	}
8456
8457drop:
8458	kfree_skb(skb);
8459}
8460
8461static struct hci_cb l2cap_cb = {
8462	.name		= "L2CAP",
8463	.connect_cfm	= l2cap_connect_cfm,
8464	.disconn_cfm	= l2cap_disconn_cfm,
8465	.security_cfm	= l2cap_security_cfm,
8466};
8467
8468static int l2cap_debugfs_show(struct seq_file *f, void *p)
8469{
8470	struct l2cap_chan *c;
8471
8472	read_lock(&chan_list_lock);
8473
8474	list_for_each_entry(c, &chan_list, global_l) {
8475		seq_printf(f, "%pMR (%u) %pMR (%u) %d %d 0x%4.4x 0x%4.4x %d %d %d %d\n",
8476			   &c->src, c->src_type, &c->dst, c->dst_type,
8477			   c->state, __le16_to_cpu(c->psm),
8478			   c->scid, c->dcid, c->imtu, c->omtu,
8479			   c->sec_level, c->mode);
8480	}
8481
8482	read_unlock(&chan_list_lock);
8483
8484	return 0;
8485}
8486
8487DEFINE_SHOW_ATTRIBUTE(l2cap_debugfs);
 
 
 
 
 
 
 
 
 
 
8488
8489static struct dentry *l2cap_debugfs;
8490
8491int __init l2cap_init(void)
8492{
8493	int err;
8494
8495	err = l2cap_init_sockets();
8496	if (err < 0)
8497		return err;
8498
8499	hci_register_cb(&l2cap_cb);
8500
8501	if (IS_ERR_OR_NULL(bt_debugfs))
8502		return 0;
8503
8504	l2cap_debugfs = debugfs_create_file("l2cap", 0444, bt_debugfs,
8505					    NULL, &l2cap_debugfs_fops);
8506
 
 
 
 
 
8507	return 0;
8508}
8509
8510void l2cap_exit(void)
8511{
8512	debugfs_remove(l2cap_debugfs);
8513	hci_unregister_cb(&l2cap_cb);
8514	l2cap_cleanup_sockets();
8515}
8516
8517module_param(disable_ertm, bool, 0644);
8518MODULE_PARM_DESC(disable_ertm, "Disable enhanced retransmission mode");
8519
8520module_param(enable_ecred, bool, 0644);
8521MODULE_PARM_DESC(enable_ecred, "Enable enhanced credit flow control mode");