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v6.8
   1/*
   2   RFCOMM implementation for Linux Bluetooth stack (BlueZ).
   3   Copyright (C) 2002 Maxim Krasnyansky <maxk@qualcomm.com>
   4   Copyright (C) 2002 Marcel Holtmann <marcel@holtmann.org>
   5
   6   This program is free software; you can redistribute it and/or modify
   7   it under the terms of the GNU General Public License version 2 as
   8   published by the Free Software Foundation;
   9
  10   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  11   OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  12   FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS.
  13   IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) AND AUTHOR(S) BE LIABLE FOR ANY
  14   CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES
  15   WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  16   ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  17   OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  18
  19   ALL LIABILITY, INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PATENTS,
  20   COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS, RELATING TO USE OF THIS
  21   SOFTWARE IS DISCLAIMED.
  22*/
  23
  24/*
  25 * Bluetooth RFCOMM core.
  26 */
  27
  28#include <linux/module.h>
  29#include <linux/debugfs.h>
  30#include <linux/kthread.h>
  31#include <asm/unaligned.h>
  32
  33#include <net/bluetooth/bluetooth.h>
  34#include <net/bluetooth/hci_core.h>
  35#include <net/bluetooth/l2cap.h>
  36#include <net/bluetooth/rfcomm.h>
  37
  38#include <trace/events/sock.h>
  39
  40#define VERSION "1.11"
  41
  42static bool disable_cfc;
  43static bool l2cap_ertm;
  44static int channel_mtu = -1;
  45
  46static struct task_struct *rfcomm_thread;
  47
  48static DEFINE_MUTEX(rfcomm_mutex);
  49#define rfcomm_lock()	mutex_lock(&rfcomm_mutex)
  50#define rfcomm_unlock()	mutex_unlock(&rfcomm_mutex)
  51
  52
  53static LIST_HEAD(session_list);
  54
  55static int rfcomm_send_frame(struct rfcomm_session *s, u8 *data, int len);
  56static int rfcomm_send_sabm(struct rfcomm_session *s, u8 dlci);
  57static int rfcomm_send_disc(struct rfcomm_session *s, u8 dlci);
  58static int rfcomm_queue_disc(struct rfcomm_dlc *d);
  59static int rfcomm_send_nsc(struct rfcomm_session *s, int cr, u8 type);
  60static int rfcomm_send_pn(struct rfcomm_session *s, int cr, struct rfcomm_dlc *d);
  61static int rfcomm_send_msc(struct rfcomm_session *s, int cr, u8 dlci, u8 v24_sig);
  62static int rfcomm_send_test(struct rfcomm_session *s, int cr, u8 *pattern, int len);
  63static int rfcomm_send_credits(struct rfcomm_session *s, u8 addr, u8 credits);
  64static void rfcomm_make_uih(struct sk_buff *skb, u8 addr);
  65
  66static void rfcomm_process_connect(struct rfcomm_session *s);
  67
  68static struct rfcomm_session *rfcomm_session_create(bdaddr_t *src,
  69							bdaddr_t *dst,
  70							u8 sec_level,
  71							int *err);
  72static struct rfcomm_session *rfcomm_session_get(bdaddr_t *src, bdaddr_t *dst);
  73static struct rfcomm_session *rfcomm_session_del(struct rfcomm_session *s);
  74
  75/* ---- RFCOMM frame parsing macros ---- */
  76#define __get_dlci(b)     ((b & 0xfc) >> 2)
  77#define __get_type(b)     ((b & 0xef))
  78
  79#define __test_ea(b)      ((b & 0x01))
  80#define __test_cr(b)      (!!(b & 0x02))
  81#define __test_pf(b)      (!!(b & 0x10))
  82
  83#define __session_dir(s)  ((s)->initiator ? 0x00 : 0x01)
  84
  85#define __addr(cr, dlci)       (((dlci & 0x3f) << 2) | (cr << 1) | 0x01)
  86#define __ctrl(type, pf)       (((type & 0xef) | (pf << 4)))
  87#define __dlci(dir, chn)       (((chn & 0x1f) << 1) | dir)
  88#define __srv_channel(dlci)    (dlci >> 1)
  89
  90#define __len8(len)       (((len) << 1) | 1)
  91#define __len16(len)      ((len) << 1)
  92
  93/* MCC macros */
  94#define __mcc_type(cr, type)   (((type << 2) | (cr << 1) | 0x01))
  95#define __get_mcc_type(b) ((b & 0xfc) >> 2)
  96#define __get_mcc_len(b)  ((b & 0xfe) >> 1)
  97
  98/* RPN macros */
  99#define __rpn_line_settings(data, stop, parity)  ((data & 0x3) | ((stop & 0x1) << 2) | ((parity & 0x7) << 3))
 100#define __get_rpn_data_bits(line) ((line) & 0x3)
 101#define __get_rpn_stop_bits(line) (((line) >> 2) & 0x1)
 102#define __get_rpn_parity(line)    (((line) >> 3) & 0x7)
 103
 104static DECLARE_WAIT_QUEUE_HEAD(rfcomm_wq);
 105
 106static void rfcomm_schedule(void)
 107{
 108	wake_up_all(&rfcomm_wq);
 109}
 110
 111/* ---- RFCOMM FCS computation ---- */
 112
 113/* reversed, 8-bit, poly=0x07 */
 114static unsigned char rfcomm_crc_table[256] = {
 115	0x00, 0x91, 0xe3, 0x72, 0x07, 0x96, 0xe4, 0x75,
 116	0x0e, 0x9f, 0xed, 0x7c, 0x09, 0x98, 0xea, 0x7b,
 117	0x1c, 0x8d, 0xff, 0x6e, 0x1b, 0x8a, 0xf8, 0x69,
 118	0x12, 0x83, 0xf1, 0x60, 0x15, 0x84, 0xf6, 0x67,
 119
 120	0x38, 0xa9, 0xdb, 0x4a, 0x3f, 0xae, 0xdc, 0x4d,
 121	0x36, 0xa7, 0xd5, 0x44, 0x31, 0xa0, 0xd2, 0x43,
 122	0x24, 0xb5, 0xc7, 0x56, 0x23, 0xb2, 0xc0, 0x51,
 123	0x2a, 0xbb, 0xc9, 0x58, 0x2d, 0xbc, 0xce, 0x5f,
 124
 125	0x70, 0xe1, 0x93, 0x02, 0x77, 0xe6, 0x94, 0x05,
 126	0x7e, 0xef, 0x9d, 0x0c, 0x79, 0xe8, 0x9a, 0x0b,
 127	0x6c, 0xfd, 0x8f, 0x1e, 0x6b, 0xfa, 0x88, 0x19,
 128	0x62, 0xf3, 0x81, 0x10, 0x65, 0xf4, 0x86, 0x17,
 129
 130	0x48, 0xd9, 0xab, 0x3a, 0x4f, 0xde, 0xac, 0x3d,
 131	0x46, 0xd7, 0xa5, 0x34, 0x41, 0xd0, 0xa2, 0x33,
 132	0x54, 0xc5, 0xb7, 0x26, 0x53, 0xc2, 0xb0, 0x21,
 133	0x5a, 0xcb, 0xb9, 0x28, 0x5d, 0xcc, 0xbe, 0x2f,
 134
 135	0xe0, 0x71, 0x03, 0x92, 0xe7, 0x76, 0x04, 0x95,
 136	0xee, 0x7f, 0x0d, 0x9c, 0xe9, 0x78, 0x0a, 0x9b,
 137	0xfc, 0x6d, 0x1f, 0x8e, 0xfb, 0x6a, 0x18, 0x89,
 138	0xf2, 0x63, 0x11, 0x80, 0xf5, 0x64, 0x16, 0x87,
 139
 140	0xd8, 0x49, 0x3b, 0xaa, 0xdf, 0x4e, 0x3c, 0xad,
 141	0xd6, 0x47, 0x35, 0xa4, 0xd1, 0x40, 0x32, 0xa3,
 142	0xc4, 0x55, 0x27, 0xb6, 0xc3, 0x52, 0x20, 0xb1,
 143	0xca, 0x5b, 0x29, 0xb8, 0xcd, 0x5c, 0x2e, 0xbf,
 144
 145	0x90, 0x01, 0x73, 0xe2, 0x97, 0x06, 0x74, 0xe5,
 146	0x9e, 0x0f, 0x7d, 0xec, 0x99, 0x08, 0x7a, 0xeb,
 147	0x8c, 0x1d, 0x6f, 0xfe, 0x8b, 0x1a, 0x68, 0xf9,
 148	0x82, 0x13, 0x61, 0xf0, 0x85, 0x14, 0x66, 0xf7,
 149
 150	0xa8, 0x39, 0x4b, 0xda, 0xaf, 0x3e, 0x4c, 0xdd,
 151	0xa6, 0x37, 0x45, 0xd4, 0xa1, 0x30, 0x42, 0xd3,
 152	0xb4, 0x25, 0x57, 0xc6, 0xb3, 0x22, 0x50, 0xc1,
 153	0xba, 0x2b, 0x59, 0xc8, 0xbd, 0x2c, 0x5e, 0xcf
 154};
 155
 156/* CRC on 2 bytes */
 157#define __crc(data) (rfcomm_crc_table[rfcomm_crc_table[0xff ^ data[0]] ^ data[1]])
 158
 159/* FCS on 2 bytes */
 160static inline u8 __fcs(u8 *data)
 161{
 162	return 0xff - __crc(data);
 163}
 164
 165/* FCS on 3 bytes */
 166static inline u8 __fcs2(u8 *data)
 167{
 168	return 0xff - rfcomm_crc_table[__crc(data) ^ data[2]];
 169}
 170
 171/* Check FCS */
 172static inline int __check_fcs(u8 *data, int type, u8 fcs)
 173{
 174	u8 f = __crc(data);
 175
 176	if (type != RFCOMM_UIH)
 177		f = rfcomm_crc_table[f ^ data[2]];
 178
 179	return rfcomm_crc_table[f ^ fcs] != 0xcf;
 180}
 181
 182/* ---- L2CAP callbacks ---- */
 183static void rfcomm_l2state_change(struct sock *sk)
 184{
 185	BT_DBG("%p state %d", sk, sk->sk_state);
 186	rfcomm_schedule();
 187}
 188
 189static void rfcomm_l2data_ready(struct sock *sk)
 190{
 191	trace_sk_data_ready(sk);
 192
 193	BT_DBG("%p", sk);
 194	rfcomm_schedule();
 195}
 196
 197static int rfcomm_l2sock_create(struct socket **sock)
 198{
 199	int err;
 200
 201	BT_DBG("");
 202
 203	err = sock_create_kern(&init_net, PF_BLUETOOTH, SOCK_SEQPACKET, BTPROTO_L2CAP, sock);
 204	if (!err) {
 205		struct sock *sk = (*sock)->sk;
 206		sk->sk_data_ready   = rfcomm_l2data_ready;
 207		sk->sk_state_change = rfcomm_l2state_change;
 208	}
 209	return err;
 210}
 211
 212static int rfcomm_check_security(struct rfcomm_dlc *d)
 213{
 214	struct sock *sk = d->session->sock->sk;
 215	struct l2cap_conn *conn = l2cap_pi(sk)->chan->conn;
 216
 217	__u8 auth_type;
 218
 219	switch (d->sec_level) {
 220	case BT_SECURITY_HIGH:
 221	case BT_SECURITY_FIPS:
 222		auth_type = HCI_AT_GENERAL_BONDING_MITM;
 223		break;
 224	case BT_SECURITY_MEDIUM:
 225		auth_type = HCI_AT_GENERAL_BONDING;
 226		break;
 227	default:
 228		auth_type = HCI_AT_NO_BONDING;
 229		break;
 230	}
 231
 232	return hci_conn_security(conn->hcon, d->sec_level, auth_type,
 233				 d->out);
 234}
 235
 236static void rfcomm_session_timeout(struct timer_list *t)
 237{
 238	struct rfcomm_session *s = from_timer(s, t, timer);
 239
 240	BT_DBG("session %p state %ld", s, s->state);
 241
 242	set_bit(RFCOMM_TIMED_OUT, &s->flags);
 243	rfcomm_schedule();
 244}
 245
 246static void rfcomm_session_set_timer(struct rfcomm_session *s, long timeout)
 247{
 248	BT_DBG("session %p state %ld timeout %ld", s, s->state, timeout);
 249
 250	mod_timer(&s->timer, jiffies + timeout);
 251}
 252
 253static void rfcomm_session_clear_timer(struct rfcomm_session *s)
 254{
 255	BT_DBG("session %p state %ld", s, s->state);
 256
 257	del_timer_sync(&s->timer);
 258}
 259
 260/* ---- RFCOMM DLCs ---- */
 261static void rfcomm_dlc_timeout(struct timer_list *t)
 262{
 263	struct rfcomm_dlc *d = from_timer(d, t, timer);
 264
 265	BT_DBG("dlc %p state %ld", d, d->state);
 266
 267	set_bit(RFCOMM_TIMED_OUT, &d->flags);
 268	rfcomm_dlc_put(d);
 269	rfcomm_schedule();
 270}
 271
 272static void rfcomm_dlc_set_timer(struct rfcomm_dlc *d, long timeout)
 273{
 274	BT_DBG("dlc %p state %ld timeout %ld", d, d->state, timeout);
 275
 276	if (!mod_timer(&d->timer, jiffies + timeout))
 277		rfcomm_dlc_hold(d);
 278}
 279
 280static void rfcomm_dlc_clear_timer(struct rfcomm_dlc *d)
 281{
 282	BT_DBG("dlc %p state %ld", d, d->state);
 283
 284	if (del_timer(&d->timer))
 285		rfcomm_dlc_put(d);
 286}
 287
 288static void rfcomm_dlc_clear_state(struct rfcomm_dlc *d)
 289{
 290	BT_DBG("%p", d);
 291
 292	d->state      = BT_OPEN;
 293	d->flags      = 0;
 294	d->mscex      = 0;
 295	d->sec_level  = BT_SECURITY_LOW;
 296	d->mtu        = RFCOMM_DEFAULT_MTU;
 297	d->v24_sig    = RFCOMM_V24_RTC | RFCOMM_V24_RTR | RFCOMM_V24_DV;
 298
 299	d->cfc        = RFCOMM_CFC_DISABLED;
 300	d->rx_credits = RFCOMM_DEFAULT_CREDITS;
 301}
 302
 303struct rfcomm_dlc *rfcomm_dlc_alloc(gfp_t prio)
 304{
 305	struct rfcomm_dlc *d = kzalloc(sizeof(*d), prio);
 306
 307	if (!d)
 308		return NULL;
 309
 310	timer_setup(&d->timer, rfcomm_dlc_timeout, 0);
 311
 312	skb_queue_head_init(&d->tx_queue);
 313	mutex_init(&d->lock);
 314	refcount_set(&d->refcnt, 1);
 315
 316	rfcomm_dlc_clear_state(d);
 317
 318	BT_DBG("%p", d);
 319
 320	return d;
 321}
 322
 323void rfcomm_dlc_free(struct rfcomm_dlc *d)
 324{
 325	BT_DBG("%p", d);
 326
 327	skb_queue_purge(&d->tx_queue);
 328	kfree(d);
 329}
 330
 331static void rfcomm_dlc_link(struct rfcomm_session *s, struct rfcomm_dlc *d)
 332{
 333	BT_DBG("dlc %p session %p", d, s);
 334
 335	rfcomm_session_clear_timer(s);
 336	rfcomm_dlc_hold(d);
 337	list_add(&d->list, &s->dlcs);
 338	d->session = s;
 339}
 340
 341static void rfcomm_dlc_unlink(struct rfcomm_dlc *d)
 342{
 343	struct rfcomm_session *s = d->session;
 344
 345	BT_DBG("dlc %p refcnt %d session %p", d, refcount_read(&d->refcnt), s);
 346
 347	list_del(&d->list);
 348	d->session = NULL;
 349	rfcomm_dlc_put(d);
 350
 351	if (list_empty(&s->dlcs))
 352		rfcomm_session_set_timer(s, RFCOMM_IDLE_TIMEOUT);
 353}
 354
 355static struct rfcomm_dlc *rfcomm_dlc_get(struct rfcomm_session *s, u8 dlci)
 356{
 357	struct rfcomm_dlc *d;
 358
 359	list_for_each_entry(d, &s->dlcs, list)
 360		if (d->dlci == dlci)
 361			return d;
 362
 363	return NULL;
 364}
 365
 366static int rfcomm_check_channel(u8 channel)
 367{
 368	return channel < 1 || channel > 30;
 369}
 370
 371static int __rfcomm_dlc_open(struct rfcomm_dlc *d, bdaddr_t *src, bdaddr_t *dst, u8 channel)
 372{
 373	struct rfcomm_session *s;
 374	int err = 0;
 375	u8 dlci;
 376
 377	BT_DBG("dlc %p state %ld %pMR -> %pMR channel %d",
 378	       d, d->state, src, dst, channel);
 379
 380	if (rfcomm_check_channel(channel))
 381		return -EINVAL;
 382
 383	if (d->state != BT_OPEN && d->state != BT_CLOSED)
 384		return 0;
 385
 386	s = rfcomm_session_get(src, dst);
 387	if (!s) {
 388		s = rfcomm_session_create(src, dst, d->sec_level, &err);
 389		if (!s)
 390			return err;
 391	}
 392
 393	dlci = __dlci(__session_dir(s), channel);
 394
 395	/* Check if DLCI already exists */
 396	if (rfcomm_dlc_get(s, dlci))
 397		return -EBUSY;
 398
 399	rfcomm_dlc_clear_state(d);
 400
 401	d->dlci     = dlci;
 402	d->addr     = __addr(s->initiator, dlci);
 403	d->priority = 7;
 404
 405	d->state = BT_CONFIG;
 406	rfcomm_dlc_link(s, d);
 407
 408	d->out = 1;
 409
 410	d->mtu = s->mtu;
 411	d->cfc = (s->cfc == RFCOMM_CFC_UNKNOWN) ? 0 : s->cfc;
 412
 413	if (s->state == BT_CONNECTED) {
 414		if (rfcomm_check_security(d))
 415			rfcomm_send_pn(s, 1, d);
 416		else
 417			set_bit(RFCOMM_AUTH_PENDING, &d->flags);
 418	}
 419
 420	rfcomm_dlc_set_timer(d, RFCOMM_CONN_TIMEOUT);
 421
 422	return 0;
 423}
 424
 425int rfcomm_dlc_open(struct rfcomm_dlc *d, bdaddr_t *src, bdaddr_t *dst, u8 channel)
 426{
 427	int r;
 428
 429	rfcomm_lock();
 430
 431	r = __rfcomm_dlc_open(d, src, dst, channel);
 432
 433	rfcomm_unlock();
 434	return r;
 435}
 436
 437static void __rfcomm_dlc_disconn(struct rfcomm_dlc *d)
 438{
 439	struct rfcomm_session *s = d->session;
 440
 441	d->state = BT_DISCONN;
 442	if (skb_queue_empty(&d->tx_queue)) {
 443		rfcomm_send_disc(s, d->dlci);
 444		rfcomm_dlc_set_timer(d, RFCOMM_DISC_TIMEOUT);
 445	} else {
 446		rfcomm_queue_disc(d);
 447		rfcomm_dlc_set_timer(d, RFCOMM_DISC_TIMEOUT * 2);
 448	}
 449}
 450
 451static int __rfcomm_dlc_close(struct rfcomm_dlc *d, int err)
 452{
 453	struct rfcomm_session *s = d->session;
 454	if (!s)
 455		return 0;
 456
 457	BT_DBG("dlc %p state %ld dlci %d err %d session %p",
 458			d, d->state, d->dlci, err, s);
 459
 460	switch (d->state) {
 461	case BT_CONNECT:
 462	case BT_CONFIG:
 463	case BT_OPEN:
 464	case BT_CONNECT2:
 465		if (test_and_clear_bit(RFCOMM_DEFER_SETUP, &d->flags)) {
 466			set_bit(RFCOMM_AUTH_REJECT, &d->flags);
 467			rfcomm_schedule();
 468			return 0;
 469		}
 470	}
 471
 472	switch (d->state) {
 473	case BT_CONNECT:
 474	case BT_CONNECTED:
 475		__rfcomm_dlc_disconn(d);
 476		break;
 477
 478	case BT_CONFIG:
 479		if (s->state != BT_BOUND) {
 480			__rfcomm_dlc_disconn(d);
 481			break;
 482		}
 483		/* if closing a dlc in a session that hasn't been started,
 484		 * just close and unlink the dlc
 485		 */
 486		fallthrough;
 487
 488	default:
 489		rfcomm_dlc_clear_timer(d);
 490
 491		rfcomm_dlc_lock(d);
 492		d->state = BT_CLOSED;
 493		d->state_change(d, err);
 494		rfcomm_dlc_unlock(d);
 495
 496		skb_queue_purge(&d->tx_queue);
 497		rfcomm_dlc_unlink(d);
 498	}
 499
 500	return 0;
 501}
 502
 503int rfcomm_dlc_close(struct rfcomm_dlc *d, int err)
 504{
 505	int r = 0;
 506	struct rfcomm_dlc *d_list;
 507	struct rfcomm_session *s, *s_list;
 508
 509	BT_DBG("dlc %p state %ld dlci %d err %d", d, d->state, d->dlci, err);
 510
 511	rfcomm_lock();
 512
 513	s = d->session;
 514	if (!s)
 515		goto no_session;
 516
 517	/* after waiting on the mutex check the session still exists
 518	 * then check the dlc still exists
 519	 */
 520	list_for_each_entry(s_list, &session_list, list) {
 521		if (s_list == s) {
 522			list_for_each_entry(d_list, &s->dlcs, list) {
 523				if (d_list == d) {
 524					r = __rfcomm_dlc_close(d, err);
 525					break;
 526				}
 527			}
 528			break;
 529		}
 530	}
 531
 532no_session:
 533	rfcomm_unlock();
 534	return r;
 535}
 536
 537struct rfcomm_dlc *rfcomm_dlc_exists(bdaddr_t *src, bdaddr_t *dst, u8 channel)
 538{
 539	struct rfcomm_session *s;
 540	struct rfcomm_dlc *dlc = NULL;
 541	u8 dlci;
 542
 543	if (rfcomm_check_channel(channel))
 544		return ERR_PTR(-EINVAL);
 545
 546	rfcomm_lock();
 547	s = rfcomm_session_get(src, dst);
 548	if (s) {
 549		dlci = __dlci(__session_dir(s), channel);
 550		dlc = rfcomm_dlc_get(s, dlci);
 551	}
 552	rfcomm_unlock();
 553	return dlc;
 554}
 555
 556static int rfcomm_dlc_send_frag(struct rfcomm_dlc *d, struct sk_buff *frag)
 557{
 558	int len = frag->len;
 559
 560	BT_DBG("dlc %p mtu %d len %d", d, d->mtu, len);
 561
 562	if (len > d->mtu)
 563		return -EINVAL;
 564
 565	rfcomm_make_uih(frag, d->addr);
 566	__skb_queue_tail(&d->tx_queue, frag);
 567
 568	return len;
 569}
 570
 571int rfcomm_dlc_send(struct rfcomm_dlc *d, struct sk_buff *skb)
 572{
 573	unsigned long flags;
 574	struct sk_buff *frag, *next;
 575	int len;
 576
 577	if (d->state != BT_CONNECTED)
 578		return -ENOTCONN;
 579
 580	frag = skb_shinfo(skb)->frag_list;
 581	skb_shinfo(skb)->frag_list = NULL;
 582
 583	/* Queue all fragments atomically. */
 584	spin_lock_irqsave(&d->tx_queue.lock, flags);
 585
 586	len = rfcomm_dlc_send_frag(d, skb);
 587	if (len < 0 || !frag)
 588		goto unlock;
 589
 590	for (; frag; frag = next) {
 591		int ret;
 592
 593		next = frag->next;
 594
 595		ret = rfcomm_dlc_send_frag(d, frag);
 596		if (ret < 0) {
 597			dev_kfree_skb_irq(frag);
 598			goto unlock;
 599		}
 600
 601		len += ret;
 602	}
 603
 604unlock:
 605	spin_unlock_irqrestore(&d->tx_queue.lock, flags);
 606
 607	if (len > 0 && !test_bit(RFCOMM_TX_THROTTLED, &d->flags))
 608		rfcomm_schedule();
 609	return len;
 610}
 611
 612void rfcomm_dlc_send_noerror(struct rfcomm_dlc *d, struct sk_buff *skb)
 613{
 614	int len = skb->len;
 615
 616	BT_DBG("dlc %p mtu %d len %d", d, d->mtu, len);
 617
 618	rfcomm_make_uih(skb, d->addr);
 619	skb_queue_tail(&d->tx_queue, skb);
 620
 621	if (d->state == BT_CONNECTED &&
 622	    !test_bit(RFCOMM_TX_THROTTLED, &d->flags))
 623		rfcomm_schedule();
 624}
 625
 626void __rfcomm_dlc_throttle(struct rfcomm_dlc *d)
 627{
 628	BT_DBG("dlc %p state %ld", d, d->state);
 629
 630	if (!d->cfc) {
 631		d->v24_sig |= RFCOMM_V24_FC;
 632		set_bit(RFCOMM_MSC_PENDING, &d->flags);
 633	}
 634	rfcomm_schedule();
 635}
 636
 637void __rfcomm_dlc_unthrottle(struct rfcomm_dlc *d)
 638{
 639	BT_DBG("dlc %p state %ld", d, d->state);
 640
 641	if (!d->cfc) {
 642		d->v24_sig &= ~RFCOMM_V24_FC;
 643		set_bit(RFCOMM_MSC_PENDING, &d->flags);
 644	}
 645	rfcomm_schedule();
 646}
 647
 648/*
 649   Set/get modem status functions use _local_ status i.e. what we report
 650   to the other side.
 651   Remote status is provided by dlc->modem_status() callback.
 652 */
 653int rfcomm_dlc_set_modem_status(struct rfcomm_dlc *d, u8 v24_sig)
 654{
 655	BT_DBG("dlc %p state %ld v24_sig 0x%x",
 656			d, d->state, v24_sig);
 657
 658	if (test_bit(RFCOMM_RX_THROTTLED, &d->flags))
 659		v24_sig |= RFCOMM_V24_FC;
 660	else
 661		v24_sig &= ~RFCOMM_V24_FC;
 662
 663	d->v24_sig = v24_sig;
 664
 665	if (!test_and_set_bit(RFCOMM_MSC_PENDING, &d->flags))
 666		rfcomm_schedule();
 667
 668	return 0;
 669}
 670
 671int rfcomm_dlc_get_modem_status(struct rfcomm_dlc *d, u8 *v24_sig)
 672{
 673	BT_DBG("dlc %p state %ld v24_sig 0x%x",
 674			d, d->state, d->v24_sig);
 675
 676	*v24_sig = d->v24_sig;
 677	return 0;
 678}
 679
 680/* ---- RFCOMM sessions ---- */
 681static struct rfcomm_session *rfcomm_session_add(struct socket *sock, int state)
 682{
 683	struct rfcomm_session *s = kzalloc(sizeof(*s), GFP_KERNEL);
 684
 685	if (!s)
 686		return NULL;
 687
 688	BT_DBG("session %p sock %p", s, sock);
 689
 690	timer_setup(&s->timer, rfcomm_session_timeout, 0);
 691
 692	INIT_LIST_HEAD(&s->dlcs);
 693	s->state = state;
 694	s->sock  = sock;
 695
 696	s->mtu = RFCOMM_DEFAULT_MTU;
 697	s->cfc = disable_cfc ? RFCOMM_CFC_DISABLED : RFCOMM_CFC_UNKNOWN;
 698
 699	/* Do not increment module usage count for listening sessions.
 700	 * Otherwise we won't be able to unload the module. */
 701	if (state != BT_LISTEN)
 702		if (!try_module_get(THIS_MODULE)) {
 703			kfree(s);
 704			return NULL;
 705		}
 706
 707	list_add(&s->list, &session_list);
 708
 709	return s;
 710}
 711
 712static struct rfcomm_session *rfcomm_session_del(struct rfcomm_session *s)
 713{
 714	int state = s->state;
 715
 716	BT_DBG("session %p state %ld", s, s->state);
 717
 718	list_del(&s->list);
 719
 720	rfcomm_session_clear_timer(s);
 721	sock_release(s->sock);
 722	kfree(s);
 723
 724	if (state != BT_LISTEN)
 725		module_put(THIS_MODULE);
 726
 727	return NULL;
 728}
 729
 730static struct rfcomm_session *rfcomm_session_get(bdaddr_t *src, bdaddr_t *dst)
 731{
 732	struct rfcomm_session *s, *n;
 733	struct l2cap_chan *chan;
 734	list_for_each_entry_safe(s, n, &session_list, list) {
 735		chan = l2cap_pi(s->sock->sk)->chan;
 736
 737		if ((!bacmp(src, BDADDR_ANY) || !bacmp(&chan->src, src)) &&
 738		    !bacmp(&chan->dst, dst))
 739			return s;
 740	}
 741	return NULL;
 742}
 743
 744static struct rfcomm_session *rfcomm_session_close(struct rfcomm_session *s,
 745						   int err)
 746{
 747	struct rfcomm_dlc *d, *n;
 748
 749	s->state = BT_CLOSED;
 750
 751	BT_DBG("session %p state %ld err %d", s, s->state, err);
 752
 753	/* Close all dlcs */
 754	list_for_each_entry_safe(d, n, &s->dlcs, list) {
 755		d->state = BT_CLOSED;
 756		__rfcomm_dlc_close(d, err);
 757	}
 758
 759	rfcomm_session_clear_timer(s);
 760	return rfcomm_session_del(s);
 761}
 762
 763static struct rfcomm_session *rfcomm_session_create(bdaddr_t *src,
 764							bdaddr_t *dst,
 765							u8 sec_level,
 766							int *err)
 767{
 768	struct rfcomm_session *s = NULL;
 769	struct sockaddr_l2 addr;
 770	struct socket *sock;
 771	struct sock *sk;
 772
 773	BT_DBG("%pMR -> %pMR", src, dst);
 774
 775	*err = rfcomm_l2sock_create(&sock);
 776	if (*err < 0)
 777		return NULL;
 778
 779	bacpy(&addr.l2_bdaddr, src);
 780	addr.l2_family = AF_BLUETOOTH;
 781	addr.l2_psm    = 0;
 782	addr.l2_cid    = 0;
 783	addr.l2_bdaddr_type = BDADDR_BREDR;
 784	*err = kernel_bind(sock, (struct sockaddr *) &addr, sizeof(addr));
 785	if (*err < 0)
 786		goto failed;
 787
 788	/* Set L2CAP options */
 789	sk = sock->sk;
 790	lock_sock(sk);
 791	/* Set MTU to 0 so L2CAP can auto select the MTU */
 792	l2cap_pi(sk)->chan->imtu = 0;
 793	l2cap_pi(sk)->chan->sec_level = sec_level;
 794	if (l2cap_ertm)
 795		l2cap_pi(sk)->chan->mode = L2CAP_MODE_ERTM;
 796	release_sock(sk);
 797
 798	s = rfcomm_session_add(sock, BT_BOUND);
 799	if (!s) {
 800		*err = -ENOMEM;
 801		goto failed;
 802	}
 803
 804	s->initiator = 1;
 805
 806	bacpy(&addr.l2_bdaddr, dst);
 807	addr.l2_family = AF_BLUETOOTH;
 808	addr.l2_psm    = cpu_to_le16(L2CAP_PSM_RFCOMM);
 809	addr.l2_cid    = 0;
 810	addr.l2_bdaddr_type = BDADDR_BREDR;
 811	*err = kernel_connect(sock, (struct sockaddr *) &addr, sizeof(addr), O_NONBLOCK);
 812	if (*err == 0 || *err == -EINPROGRESS)
 813		return s;
 814
 815	return rfcomm_session_del(s);
 816
 817failed:
 818	sock_release(sock);
 819	return NULL;
 820}
 821
 822void rfcomm_session_getaddr(struct rfcomm_session *s, bdaddr_t *src, bdaddr_t *dst)
 823{
 824	struct l2cap_chan *chan = l2cap_pi(s->sock->sk)->chan;
 825	if (src)
 826		bacpy(src, &chan->src);
 827	if (dst)
 828		bacpy(dst, &chan->dst);
 829}
 830
 831/* ---- RFCOMM frame sending ---- */
 832static int rfcomm_send_frame(struct rfcomm_session *s, u8 *data, int len)
 833{
 834	struct kvec iv = { data, len };
 835	struct msghdr msg;
 836
 837	BT_DBG("session %p len %d", s, len);
 838
 839	memset(&msg, 0, sizeof(msg));
 840
 841	return kernel_sendmsg(s->sock, &msg, &iv, 1, len);
 842}
 843
 844static int rfcomm_send_cmd(struct rfcomm_session *s, struct rfcomm_cmd *cmd)
 845{
 846	BT_DBG("%p cmd %u", s, cmd->ctrl);
 847
 848	return rfcomm_send_frame(s, (void *) cmd, sizeof(*cmd));
 849}
 850
 851static int rfcomm_send_sabm(struct rfcomm_session *s, u8 dlci)
 852{
 853	struct rfcomm_cmd cmd;
 854
 855	BT_DBG("%p dlci %d", s, dlci);
 856
 857	cmd.addr = __addr(s->initiator, dlci);
 858	cmd.ctrl = __ctrl(RFCOMM_SABM, 1);
 859	cmd.len  = __len8(0);
 860	cmd.fcs  = __fcs2((u8 *) &cmd);
 861
 862	return rfcomm_send_cmd(s, &cmd);
 863}
 864
 865static int rfcomm_send_ua(struct rfcomm_session *s, u8 dlci)
 866{
 867	struct rfcomm_cmd cmd;
 868
 869	BT_DBG("%p dlci %d", s, dlci);
 870
 871	cmd.addr = __addr(!s->initiator, dlci);
 872	cmd.ctrl = __ctrl(RFCOMM_UA, 1);
 873	cmd.len  = __len8(0);
 874	cmd.fcs  = __fcs2((u8 *) &cmd);
 875
 876	return rfcomm_send_cmd(s, &cmd);
 877}
 878
 879static int rfcomm_send_disc(struct rfcomm_session *s, u8 dlci)
 880{
 881	struct rfcomm_cmd cmd;
 882
 883	BT_DBG("%p dlci %d", s, dlci);
 884
 885	cmd.addr = __addr(s->initiator, dlci);
 886	cmd.ctrl = __ctrl(RFCOMM_DISC, 1);
 887	cmd.len  = __len8(0);
 888	cmd.fcs  = __fcs2((u8 *) &cmd);
 889
 890	return rfcomm_send_cmd(s, &cmd);
 891}
 892
 893static int rfcomm_queue_disc(struct rfcomm_dlc *d)
 894{
 895	struct rfcomm_cmd *cmd;
 896	struct sk_buff *skb;
 897
 898	BT_DBG("dlc %p dlci %d", d, d->dlci);
 899
 900	skb = alloc_skb(sizeof(*cmd), GFP_KERNEL);
 901	if (!skb)
 902		return -ENOMEM;
 903
 904	cmd = __skb_put(skb, sizeof(*cmd));
 905	cmd->addr = d->addr;
 906	cmd->ctrl = __ctrl(RFCOMM_DISC, 1);
 907	cmd->len  = __len8(0);
 908	cmd->fcs  = __fcs2((u8 *) cmd);
 909
 910	skb_queue_tail(&d->tx_queue, skb);
 911	rfcomm_schedule();
 912	return 0;
 913}
 914
 915static int rfcomm_send_dm(struct rfcomm_session *s, u8 dlci)
 916{
 917	struct rfcomm_cmd cmd;
 918
 919	BT_DBG("%p dlci %d", s, dlci);
 920
 921	cmd.addr = __addr(!s->initiator, dlci);
 922	cmd.ctrl = __ctrl(RFCOMM_DM, 1);
 923	cmd.len  = __len8(0);
 924	cmd.fcs  = __fcs2((u8 *) &cmd);
 925
 926	return rfcomm_send_cmd(s, &cmd);
 927}
 928
 929static int rfcomm_send_nsc(struct rfcomm_session *s, int cr, u8 type)
 930{
 931	struct rfcomm_hdr *hdr;
 932	struct rfcomm_mcc *mcc;
 933	u8 buf[16], *ptr = buf;
 934
 935	BT_DBG("%p cr %d type %d", s, cr, type);
 936
 937	hdr = (void *) ptr; ptr += sizeof(*hdr);
 938	hdr->addr = __addr(s->initiator, 0);
 939	hdr->ctrl = __ctrl(RFCOMM_UIH, 0);
 940	hdr->len  = __len8(sizeof(*mcc) + 1);
 941
 942	mcc = (void *) ptr; ptr += sizeof(*mcc);
 943	mcc->type = __mcc_type(0, RFCOMM_NSC);
 944	mcc->len  = __len8(1);
 945
 946	/* Type that we didn't like */
 947	*ptr = __mcc_type(cr, type); ptr++;
 948
 949	*ptr = __fcs(buf); ptr++;
 950
 951	return rfcomm_send_frame(s, buf, ptr - buf);
 952}
 953
 954static int rfcomm_send_pn(struct rfcomm_session *s, int cr, struct rfcomm_dlc *d)
 955{
 956	struct rfcomm_hdr *hdr;
 957	struct rfcomm_mcc *mcc;
 958	struct rfcomm_pn  *pn;
 959	u8 buf[16], *ptr = buf;
 960
 961	BT_DBG("%p cr %d dlci %d mtu %d", s, cr, d->dlci, d->mtu);
 962
 963	hdr = (void *) ptr; ptr += sizeof(*hdr);
 964	hdr->addr = __addr(s->initiator, 0);
 965	hdr->ctrl = __ctrl(RFCOMM_UIH, 0);
 966	hdr->len  = __len8(sizeof(*mcc) + sizeof(*pn));
 967
 968	mcc = (void *) ptr; ptr += sizeof(*mcc);
 969	mcc->type = __mcc_type(cr, RFCOMM_PN);
 970	mcc->len  = __len8(sizeof(*pn));
 971
 972	pn = (void *) ptr; ptr += sizeof(*pn);
 973	pn->dlci        = d->dlci;
 974	pn->priority    = d->priority;
 975	pn->ack_timer   = 0;
 976	pn->max_retrans = 0;
 977
 978	if (s->cfc) {
 979		pn->flow_ctrl = cr ? 0xf0 : 0xe0;
 980		pn->credits = RFCOMM_DEFAULT_CREDITS;
 981	} else {
 982		pn->flow_ctrl = 0;
 983		pn->credits   = 0;
 984	}
 985
 986	if (cr && channel_mtu >= 0)
 987		pn->mtu = cpu_to_le16(channel_mtu);
 988	else
 989		pn->mtu = cpu_to_le16(d->mtu);
 990
 991	*ptr = __fcs(buf); ptr++;
 992
 993	return rfcomm_send_frame(s, buf, ptr - buf);
 994}
 995
 996int rfcomm_send_rpn(struct rfcomm_session *s, int cr, u8 dlci,
 997			u8 bit_rate, u8 data_bits, u8 stop_bits,
 998			u8 parity, u8 flow_ctrl_settings,
 999			u8 xon_char, u8 xoff_char, u16 param_mask)
1000{
1001	struct rfcomm_hdr *hdr;
1002	struct rfcomm_mcc *mcc;
1003	struct rfcomm_rpn *rpn;
1004	u8 buf[16], *ptr = buf;
1005
1006	BT_DBG("%p cr %d dlci %d bit_r 0x%x data_b 0x%x stop_b 0x%x parity 0x%x"
1007			" flwc_s 0x%x xon_c 0x%x xoff_c 0x%x p_mask 0x%x",
1008		s, cr, dlci, bit_rate, data_bits, stop_bits, parity,
1009		flow_ctrl_settings, xon_char, xoff_char, param_mask);
1010
1011	hdr = (void *) ptr; ptr += sizeof(*hdr);
1012	hdr->addr = __addr(s->initiator, 0);
1013	hdr->ctrl = __ctrl(RFCOMM_UIH, 0);
1014	hdr->len  = __len8(sizeof(*mcc) + sizeof(*rpn));
1015
1016	mcc = (void *) ptr; ptr += sizeof(*mcc);
1017	mcc->type = __mcc_type(cr, RFCOMM_RPN);
1018	mcc->len  = __len8(sizeof(*rpn));
1019
1020	rpn = (void *) ptr; ptr += sizeof(*rpn);
1021	rpn->dlci          = __addr(1, dlci);
1022	rpn->bit_rate      = bit_rate;
1023	rpn->line_settings = __rpn_line_settings(data_bits, stop_bits, parity);
1024	rpn->flow_ctrl     = flow_ctrl_settings;
1025	rpn->xon_char      = xon_char;
1026	rpn->xoff_char     = xoff_char;
1027	rpn->param_mask    = cpu_to_le16(param_mask);
1028
1029	*ptr = __fcs(buf); ptr++;
1030
1031	return rfcomm_send_frame(s, buf, ptr - buf);
1032}
1033
1034static int rfcomm_send_rls(struct rfcomm_session *s, int cr, u8 dlci, u8 status)
1035{
1036	struct rfcomm_hdr *hdr;
1037	struct rfcomm_mcc *mcc;
1038	struct rfcomm_rls *rls;
1039	u8 buf[16], *ptr = buf;
1040
1041	BT_DBG("%p cr %d status 0x%x", s, cr, status);
1042
1043	hdr = (void *) ptr; ptr += sizeof(*hdr);
1044	hdr->addr = __addr(s->initiator, 0);
1045	hdr->ctrl = __ctrl(RFCOMM_UIH, 0);
1046	hdr->len  = __len8(sizeof(*mcc) + sizeof(*rls));
1047
1048	mcc = (void *) ptr; ptr += sizeof(*mcc);
1049	mcc->type = __mcc_type(cr, RFCOMM_RLS);
1050	mcc->len  = __len8(sizeof(*rls));
1051
1052	rls = (void *) ptr; ptr += sizeof(*rls);
1053	rls->dlci   = __addr(1, dlci);
1054	rls->status = status;
1055
1056	*ptr = __fcs(buf); ptr++;
1057
1058	return rfcomm_send_frame(s, buf, ptr - buf);
1059}
1060
1061static int rfcomm_send_msc(struct rfcomm_session *s, int cr, u8 dlci, u8 v24_sig)
1062{
1063	struct rfcomm_hdr *hdr;
1064	struct rfcomm_mcc *mcc;
1065	struct rfcomm_msc *msc;
1066	u8 buf[16], *ptr = buf;
1067
1068	BT_DBG("%p cr %d v24 0x%x", s, cr, v24_sig);
1069
1070	hdr = (void *) ptr; ptr += sizeof(*hdr);
1071	hdr->addr = __addr(s->initiator, 0);
1072	hdr->ctrl = __ctrl(RFCOMM_UIH, 0);
1073	hdr->len  = __len8(sizeof(*mcc) + sizeof(*msc));
1074
1075	mcc = (void *) ptr; ptr += sizeof(*mcc);
1076	mcc->type = __mcc_type(cr, RFCOMM_MSC);
1077	mcc->len  = __len8(sizeof(*msc));
1078
1079	msc = (void *) ptr; ptr += sizeof(*msc);
1080	msc->dlci    = __addr(1, dlci);
1081	msc->v24_sig = v24_sig | 0x01;
1082
1083	*ptr = __fcs(buf); ptr++;
1084
1085	return rfcomm_send_frame(s, buf, ptr - buf);
1086}
1087
1088static int rfcomm_send_fcoff(struct rfcomm_session *s, int cr)
1089{
1090	struct rfcomm_hdr *hdr;
1091	struct rfcomm_mcc *mcc;
1092	u8 buf[16], *ptr = buf;
1093
1094	BT_DBG("%p cr %d", s, cr);
1095
1096	hdr = (void *) ptr; ptr += sizeof(*hdr);
1097	hdr->addr = __addr(s->initiator, 0);
1098	hdr->ctrl = __ctrl(RFCOMM_UIH, 0);
1099	hdr->len  = __len8(sizeof(*mcc));
1100
1101	mcc = (void *) ptr; ptr += sizeof(*mcc);
1102	mcc->type = __mcc_type(cr, RFCOMM_FCOFF);
1103	mcc->len  = __len8(0);
1104
1105	*ptr = __fcs(buf); ptr++;
1106
1107	return rfcomm_send_frame(s, buf, ptr - buf);
1108}
1109
1110static int rfcomm_send_fcon(struct rfcomm_session *s, int cr)
1111{
1112	struct rfcomm_hdr *hdr;
1113	struct rfcomm_mcc *mcc;
1114	u8 buf[16], *ptr = buf;
1115
1116	BT_DBG("%p cr %d", s, cr);
1117
1118	hdr = (void *) ptr; ptr += sizeof(*hdr);
1119	hdr->addr = __addr(s->initiator, 0);
1120	hdr->ctrl = __ctrl(RFCOMM_UIH, 0);
1121	hdr->len  = __len8(sizeof(*mcc));
1122
1123	mcc = (void *) ptr; ptr += sizeof(*mcc);
1124	mcc->type = __mcc_type(cr, RFCOMM_FCON);
1125	mcc->len  = __len8(0);
1126
1127	*ptr = __fcs(buf); ptr++;
1128
1129	return rfcomm_send_frame(s, buf, ptr - buf);
1130}
1131
1132static int rfcomm_send_test(struct rfcomm_session *s, int cr, u8 *pattern, int len)
1133{
1134	struct socket *sock = s->sock;
1135	struct kvec iv[3];
1136	struct msghdr msg;
1137	unsigned char hdr[5], crc[1];
1138
1139	if (len > 125)
1140		return -EINVAL;
1141
1142	BT_DBG("%p cr %d", s, cr);
1143
1144	hdr[0] = __addr(s->initiator, 0);
1145	hdr[1] = __ctrl(RFCOMM_UIH, 0);
1146	hdr[2] = 0x01 | ((len + 2) << 1);
1147	hdr[3] = 0x01 | ((cr & 0x01) << 1) | (RFCOMM_TEST << 2);
1148	hdr[4] = 0x01 | (len << 1);
1149
1150	crc[0] = __fcs(hdr);
1151
1152	iv[0].iov_base = hdr;
1153	iv[0].iov_len  = 5;
1154	iv[1].iov_base = pattern;
1155	iv[1].iov_len  = len;
1156	iv[2].iov_base = crc;
1157	iv[2].iov_len  = 1;
1158
1159	memset(&msg, 0, sizeof(msg));
1160
1161	return kernel_sendmsg(sock, &msg, iv, 3, 6 + len);
1162}
1163
1164static int rfcomm_send_credits(struct rfcomm_session *s, u8 addr, u8 credits)
1165{
1166	struct rfcomm_hdr *hdr;
1167	u8 buf[16], *ptr = buf;
1168
1169	BT_DBG("%p addr %d credits %d", s, addr, credits);
1170
1171	hdr = (void *) ptr; ptr += sizeof(*hdr);
1172	hdr->addr = addr;
1173	hdr->ctrl = __ctrl(RFCOMM_UIH, 1);
1174	hdr->len  = __len8(0);
1175
1176	*ptr = credits; ptr++;
1177
1178	*ptr = __fcs(buf); ptr++;
1179
1180	return rfcomm_send_frame(s, buf, ptr - buf);
1181}
1182
1183static void rfcomm_make_uih(struct sk_buff *skb, u8 addr)
1184{
1185	struct rfcomm_hdr *hdr;
1186	int len = skb->len;
1187	u8 *crc;
1188
1189	if (len > 127) {
1190		hdr = skb_push(skb, 4);
1191		put_unaligned(cpu_to_le16(__len16(len)), (__le16 *) &hdr->len);
1192	} else {
1193		hdr = skb_push(skb, 3);
1194		hdr->len = __len8(len);
1195	}
1196	hdr->addr = addr;
1197	hdr->ctrl = __ctrl(RFCOMM_UIH, 0);
1198
1199	crc = skb_put(skb, 1);
1200	*crc = __fcs((void *) hdr);
1201}
1202
1203/* ---- RFCOMM frame reception ---- */
1204static struct rfcomm_session *rfcomm_recv_ua(struct rfcomm_session *s, u8 dlci)
1205{
1206	BT_DBG("session %p state %ld dlci %d", s, s->state, dlci);
1207
1208	if (dlci) {
1209		/* Data channel */
1210		struct rfcomm_dlc *d = rfcomm_dlc_get(s, dlci);
1211		if (!d) {
1212			rfcomm_send_dm(s, dlci);
1213			return s;
1214		}
1215
1216		switch (d->state) {
1217		case BT_CONNECT:
1218			rfcomm_dlc_clear_timer(d);
1219
1220			rfcomm_dlc_lock(d);
1221			d->state = BT_CONNECTED;
1222			d->state_change(d, 0);
1223			rfcomm_dlc_unlock(d);
1224
1225			rfcomm_send_msc(s, 1, dlci, d->v24_sig);
1226			break;
1227
1228		case BT_DISCONN:
1229			d->state = BT_CLOSED;
1230			__rfcomm_dlc_close(d, 0);
1231
1232			if (list_empty(&s->dlcs)) {
1233				s->state = BT_DISCONN;
1234				rfcomm_send_disc(s, 0);
1235				rfcomm_session_clear_timer(s);
1236			}
1237
1238			break;
1239		}
1240	} else {
1241		/* Control channel */
1242		switch (s->state) {
1243		case BT_CONNECT:
1244			s->state = BT_CONNECTED;
1245			rfcomm_process_connect(s);
1246			break;
1247
1248		case BT_DISCONN:
1249			s = rfcomm_session_close(s, ECONNRESET);
1250			break;
1251		}
1252	}
1253	return s;
1254}
1255
1256static struct rfcomm_session *rfcomm_recv_dm(struct rfcomm_session *s, u8 dlci)
1257{
1258	int err = 0;
1259
1260	BT_DBG("session %p state %ld dlci %d", s, s->state, dlci);
1261
1262	if (dlci) {
1263		/* Data DLC */
1264		struct rfcomm_dlc *d = rfcomm_dlc_get(s, dlci);
1265		if (d) {
1266			if (d->state == BT_CONNECT || d->state == BT_CONFIG)
1267				err = ECONNREFUSED;
1268			else
1269				err = ECONNRESET;
1270
1271			d->state = BT_CLOSED;
1272			__rfcomm_dlc_close(d, err);
1273		}
1274	} else {
1275		if (s->state == BT_CONNECT)
1276			err = ECONNREFUSED;
1277		else
1278			err = ECONNRESET;
1279
1280		s = rfcomm_session_close(s, err);
1281	}
1282	return s;
1283}
1284
1285static struct rfcomm_session *rfcomm_recv_disc(struct rfcomm_session *s,
1286					       u8 dlci)
1287{
1288	int err = 0;
1289
1290	BT_DBG("session %p state %ld dlci %d", s, s->state, dlci);
1291
1292	if (dlci) {
1293		struct rfcomm_dlc *d = rfcomm_dlc_get(s, dlci);
1294		if (d) {
1295			rfcomm_send_ua(s, dlci);
1296
1297			if (d->state == BT_CONNECT || d->state == BT_CONFIG)
1298				err = ECONNREFUSED;
1299			else
1300				err = ECONNRESET;
1301
1302			d->state = BT_CLOSED;
1303			__rfcomm_dlc_close(d, err);
1304		} else
1305			rfcomm_send_dm(s, dlci);
1306
1307	} else {
1308		rfcomm_send_ua(s, 0);
1309
1310		if (s->state == BT_CONNECT)
1311			err = ECONNREFUSED;
1312		else
1313			err = ECONNRESET;
1314
1315		s = rfcomm_session_close(s, err);
1316	}
1317	return s;
1318}
1319
1320void rfcomm_dlc_accept(struct rfcomm_dlc *d)
1321{
1322	struct sock *sk = d->session->sock->sk;
1323	struct l2cap_conn *conn = l2cap_pi(sk)->chan->conn;
1324
1325	BT_DBG("dlc %p", d);
1326
1327	rfcomm_send_ua(d->session, d->dlci);
1328
1329	rfcomm_dlc_clear_timer(d);
1330
1331	rfcomm_dlc_lock(d);
1332	d->state = BT_CONNECTED;
1333	d->state_change(d, 0);
1334	rfcomm_dlc_unlock(d);
1335
1336	if (d->role_switch)
1337		hci_conn_switch_role(conn->hcon, 0x00);
1338
1339	rfcomm_send_msc(d->session, 1, d->dlci, d->v24_sig);
1340}
1341
1342static void rfcomm_check_accept(struct rfcomm_dlc *d)
1343{
1344	if (rfcomm_check_security(d)) {
1345		if (d->defer_setup) {
1346			set_bit(RFCOMM_DEFER_SETUP, &d->flags);
1347			rfcomm_dlc_set_timer(d, RFCOMM_AUTH_TIMEOUT);
1348
1349			rfcomm_dlc_lock(d);
1350			d->state = BT_CONNECT2;
1351			d->state_change(d, 0);
1352			rfcomm_dlc_unlock(d);
1353		} else
1354			rfcomm_dlc_accept(d);
1355	} else {
1356		set_bit(RFCOMM_AUTH_PENDING, &d->flags);
1357		rfcomm_dlc_set_timer(d, RFCOMM_AUTH_TIMEOUT);
1358	}
1359}
1360
1361static int rfcomm_recv_sabm(struct rfcomm_session *s, u8 dlci)
1362{
1363	struct rfcomm_dlc *d;
1364	u8 channel;
1365
1366	BT_DBG("session %p state %ld dlci %d", s, s->state, dlci);
1367
1368	if (!dlci) {
1369		rfcomm_send_ua(s, 0);
1370
1371		if (s->state == BT_OPEN) {
1372			s->state = BT_CONNECTED;
1373			rfcomm_process_connect(s);
1374		}
1375		return 0;
1376	}
1377
1378	/* Check if DLC exists */
1379	d = rfcomm_dlc_get(s, dlci);
1380	if (d) {
1381		if (d->state == BT_OPEN) {
1382			/* DLC was previously opened by PN request */
1383			rfcomm_check_accept(d);
1384		}
1385		return 0;
1386	}
1387
1388	/* Notify socket layer about incoming connection */
1389	channel = __srv_channel(dlci);
1390	if (rfcomm_connect_ind(s, channel, &d)) {
1391		d->dlci = dlci;
1392		d->addr = __addr(s->initiator, dlci);
1393		rfcomm_dlc_link(s, d);
1394
1395		rfcomm_check_accept(d);
1396	} else {
1397		rfcomm_send_dm(s, dlci);
1398	}
1399
1400	return 0;
1401}
1402
1403static int rfcomm_apply_pn(struct rfcomm_dlc *d, int cr, struct rfcomm_pn *pn)
1404{
1405	struct rfcomm_session *s = d->session;
1406
1407	BT_DBG("dlc %p state %ld dlci %d mtu %d fc 0x%x credits %d",
1408			d, d->state, d->dlci, pn->mtu, pn->flow_ctrl, pn->credits);
1409
1410	if ((pn->flow_ctrl == 0xf0 && s->cfc != RFCOMM_CFC_DISABLED) ||
1411						pn->flow_ctrl == 0xe0) {
1412		d->cfc = RFCOMM_CFC_ENABLED;
1413		d->tx_credits = pn->credits;
1414	} else {
1415		d->cfc = RFCOMM_CFC_DISABLED;
1416		set_bit(RFCOMM_TX_THROTTLED, &d->flags);
1417	}
1418
1419	if (s->cfc == RFCOMM_CFC_UNKNOWN)
1420		s->cfc = d->cfc;
1421
1422	d->priority = pn->priority;
1423
1424	d->mtu = __le16_to_cpu(pn->mtu);
1425
1426	if (cr && d->mtu > s->mtu)
1427		d->mtu = s->mtu;
1428
1429	return 0;
1430}
1431
1432static int rfcomm_recv_pn(struct rfcomm_session *s, int cr, struct sk_buff *skb)
1433{
1434	struct rfcomm_pn *pn = (void *) skb->data;
1435	struct rfcomm_dlc *d;
1436	u8 dlci = pn->dlci;
1437
1438	BT_DBG("session %p state %ld dlci %d", s, s->state, dlci);
1439
1440	if (!dlci)
1441		return 0;
1442
1443	d = rfcomm_dlc_get(s, dlci);
1444	if (d) {
1445		if (cr) {
1446			/* PN request */
1447			rfcomm_apply_pn(d, cr, pn);
1448			rfcomm_send_pn(s, 0, d);
1449		} else {
1450			/* PN response */
1451			switch (d->state) {
1452			case BT_CONFIG:
1453				rfcomm_apply_pn(d, cr, pn);
1454
1455				d->state = BT_CONNECT;
1456				rfcomm_send_sabm(s, d->dlci);
1457				break;
1458			}
1459		}
1460	} else {
1461		u8 channel = __srv_channel(dlci);
1462
1463		if (!cr)
1464			return 0;
1465
1466		/* PN request for non existing DLC.
1467		 * Assume incoming connection. */
1468		if (rfcomm_connect_ind(s, channel, &d)) {
1469			d->dlci = dlci;
1470			d->addr = __addr(s->initiator, dlci);
1471			rfcomm_dlc_link(s, d);
1472
1473			rfcomm_apply_pn(d, cr, pn);
1474
1475			d->state = BT_OPEN;
1476			rfcomm_send_pn(s, 0, d);
1477		} else {
1478			rfcomm_send_dm(s, dlci);
1479		}
1480	}
1481	return 0;
1482}
1483
1484static int rfcomm_recv_rpn(struct rfcomm_session *s, int cr, int len, struct sk_buff *skb)
1485{
1486	struct rfcomm_rpn *rpn = (void *) skb->data;
1487	u8 dlci = __get_dlci(rpn->dlci);
1488
1489	u8 bit_rate  = 0;
1490	u8 data_bits = 0;
1491	u8 stop_bits = 0;
1492	u8 parity    = 0;
1493	u8 flow_ctrl = 0;
1494	u8 xon_char  = 0;
1495	u8 xoff_char = 0;
1496	u16 rpn_mask = RFCOMM_RPN_PM_ALL;
1497
1498	BT_DBG("dlci %d cr %d len 0x%x bitr 0x%x line 0x%x flow 0x%x xonc 0x%x xoffc 0x%x pm 0x%x",
1499		dlci, cr, len, rpn->bit_rate, rpn->line_settings, rpn->flow_ctrl,
1500		rpn->xon_char, rpn->xoff_char, rpn->param_mask);
1501
1502	if (!cr)
1503		return 0;
1504
1505	if (len == 1) {
1506		/* This is a request, return default (according to ETSI TS 07.10) settings */
1507		bit_rate  = RFCOMM_RPN_BR_9600;
1508		data_bits = RFCOMM_RPN_DATA_8;
1509		stop_bits = RFCOMM_RPN_STOP_1;
1510		parity    = RFCOMM_RPN_PARITY_NONE;
1511		flow_ctrl = RFCOMM_RPN_FLOW_NONE;
1512		xon_char  = RFCOMM_RPN_XON_CHAR;
1513		xoff_char = RFCOMM_RPN_XOFF_CHAR;
1514		goto rpn_out;
1515	}
1516
1517	/* Check for sane values, ignore/accept bit_rate, 8 bits, 1 stop bit,
1518	 * no parity, no flow control lines, normal XON/XOFF chars */
1519
1520	if (rpn->param_mask & cpu_to_le16(RFCOMM_RPN_PM_BITRATE)) {
1521		bit_rate = rpn->bit_rate;
1522		if (bit_rate > RFCOMM_RPN_BR_230400) {
1523			BT_DBG("RPN bit rate mismatch 0x%x", bit_rate);
1524			bit_rate = RFCOMM_RPN_BR_9600;
1525			rpn_mask ^= RFCOMM_RPN_PM_BITRATE;
1526		}
1527	}
1528
1529	if (rpn->param_mask & cpu_to_le16(RFCOMM_RPN_PM_DATA)) {
1530		data_bits = __get_rpn_data_bits(rpn->line_settings);
1531		if (data_bits != RFCOMM_RPN_DATA_8) {
1532			BT_DBG("RPN data bits mismatch 0x%x", data_bits);
1533			data_bits = RFCOMM_RPN_DATA_8;
1534			rpn_mask ^= RFCOMM_RPN_PM_DATA;
1535		}
1536	}
1537
1538	if (rpn->param_mask & cpu_to_le16(RFCOMM_RPN_PM_STOP)) {
1539		stop_bits = __get_rpn_stop_bits(rpn->line_settings);
1540		if (stop_bits != RFCOMM_RPN_STOP_1) {
1541			BT_DBG("RPN stop bits mismatch 0x%x", stop_bits);
1542			stop_bits = RFCOMM_RPN_STOP_1;
1543			rpn_mask ^= RFCOMM_RPN_PM_STOP;
1544		}
1545	}
1546
1547	if (rpn->param_mask & cpu_to_le16(RFCOMM_RPN_PM_PARITY)) {
1548		parity = __get_rpn_parity(rpn->line_settings);
1549		if (parity != RFCOMM_RPN_PARITY_NONE) {
1550			BT_DBG("RPN parity mismatch 0x%x", parity);
1551			parity = RFCOMM_RPN_PARITY_NONE;
1552			rpn_mask ^= RFCOMM_RPN_PM_PARITY;
1553		}
1554	}
1555
1556	if (rpn->param_mask & cpu_to_le16(RFCOMM_RPN_PM_FLOW)) {
1557		flow_ctrl = rpn->flow_ctrl;
1558		if (flow_ctrl != RFCOMM_RPN_FLOW_NONE) {
1559			BT_DBG("RPN flow ctrl mismatch 0x%x", flow_ctrl);
1560			flow_ctrl = RFCOMM_RPN_FLOW_NONE;
1561			rpn_mask ^= RFCOMM_RPN_PM_FLOW;
1562		}
1563	}
1564
1565	if (rpn->param_mask & cpu_to_le16(RFCOMM_RPN_PM_XON)) {
1566		xon_char = rpn->xon_char;
1567		if (xon_char != RFCOMM_RPN_XON_CHAR) {
1568			BT_DBG("RPN XON char mismatch 0x%x", xon_char);
1569			xon_char = RFCOMM_RPN_XON_CHAR;
1570			rpn_mask ^= RFCOMM_RPN_PM_XON;
1571		}
1572	}
1573
1574	if (rpn->param_mask & cpu_to_le16(RFCOMM_RPN_PM_XOFF)) {
1575		xoff_char = rpn->xoff_char;
1576		if (xoff_char != RFCOMM_RPN_XOFF_CHAR) {
1577			BT_DBG("RPN XOFF char mismatch 0x%x", xoff_char);
1578			xoff_char = RFCOMM_RPN_XOFF_CHAR;
1579			rpn_mask ^= RFCOMM_RPN_PM_XOFF;
1580		}
1581	}
1582
1583rpn_out:
1584	rfcomm_send_rpn(s, 0, dlci, bit_rate, data_bits, stop_bits,
1585			parity, flow_ctrl, xon_char, xoff_char, rpn_mask);
1586
1587	return 0;
1588}
1589
1590static int rfcomm_recv_rls(struct rfcomm_session *s, int cr, struct sk_buff *skb)
1591{
1592	struct rfcomm_rls *rls = (void *) skb->data;
1593	u8 dlci = __get_dlci(rls->dlci);
1594
1595	BT_DBG("dlci %d cr %d status 0x%x", dlci, cr, rls->status);
1596
1597	if (!cr)
1598		return 0;
1599
1600	/* We should probably do something with this information here. But
1601	 * for now it's sufficient just to reply -- Bluetooth 1.1 says it's
1602	 * mandatory to recognise and respond to RLS */
1603
1604	rfcomm_send_rls(s, 0, dlci, rls->status);
1605
1606	return 0;
1607}
1608
1609static int rfcomm_recv_msc(struct rfcomm_session *s, int cr, struct sk_buff *skb)
1610{
1611	struct rfcomm_msc *msc = (void *) skb->data;
1612	struct rfcomm_dlc *d;
1613	u8 dlci = __get_dlci(msc->dlci);
1614
1615	BT_DBG("dlci %d cr %d v24 0x%x", dlci, cr, msc->v24_sig);
1616
1617	d = rfcomm_dlc_get(s, dlci);
1618	if (!d)
1619		return 0;
1620
1621	if (cr) {
1622		if (msc->v24_sig & RFCOMM_V24_FC && !d->cfc)
1623			set_bit(RFCOMM_TX_THROTTLED, &d->flags);
1624		else
1625			clear_bit(RFCOMM_TX_THROTTLED, &d->flags);
1626
1627		rfcomm_dlc_lock(d);
1628
1629		d->remote_v24_sig = msc->v24_sig;
1630
1631		if (d->modem_status)
1632			d->modem_status(d, msc->v24_sig);
1633
1634		rfcomm_dlc_unlock(d);
1635
1636		rfcomm_send_msc(s, 0, dlci, msc->v24_sig);
1637
1638		d->mscex |= RFCOMM_MSCEX_RX;
1639	} else
1640		d->mscex |= RFCOMM_MSCEX_TX;
1641
1642	return 0;
1643}
1644
1645static int rfcomm_recv_mcc(struct rfcomm_session *s, struct sk_buff *skb)
1646{
1647	struct rfcomm_mcc *mcc = (void *) skb->data;
1648	u8 type, cr, len;
1649
1650	cr   = __test_cr(mcc->type);
1651	type = __get_mcc_type(mcc->type);
1652	len  = __get_mcc_len(mcc->len);
1653
1654	BT_DBG("%p type 0x%x cr %d", s, type, cr);
1655
1656	skb_pull(skb, 2);
1657
1658	switch (type) {
1659	case RFCOMM_PN:
1660		rfcomm_recv_pn(s, cr, skb);
1661		break;
1662
1663	case RFCOMM_RPN:
1664		rfcomm_recv_rpn(s, cr, len, skb);
1665		break;
1666
1667	case RFCOMM_RLS:
1668		rfcomm_recv_rls(s, cr, skb);
1669		break;
1670
1671	case RFCOMM_MSC:
1672		rfcomm_recv_msc(s, cr, skb);
1673		break;
1674
1675	case RFCOMM_FCOFF:
1676		if (cr) {
1677			set_bit(RFCOMM_TX_THROTTLED, &s->flags);
1678			rfcomm_send_fcoff(s, 0);
1679		}
1680		break;
1681
1682	case RFCOMM_FCON:
1683		if (cr) {
1684			clear_bit(RFCOMM_TX_THROTTLED, &s->flags);
1685			rfcomm_send_fcon(s, 0);
1686		}
1687		break;
1688
1689	case RFCOMM_TEST:
1690		if (cr)
1691			rfcomm_send_test(s, 0, skb->data, skb->len);
1692		break;
1693
1694	case RFCOMM_NSC:
1695		break;
1696
1697	default:
1698		BT_ERR("Unknown control type 0x%02x", type);
1699		rfcomm_send_nsc(s, cr, type);
1700		break;
1701	}
1702	return 0;
1703}
1704
1705static int rfcomm_recv_data(struct rfcomm_session *s, u8 dlci, int pf, struct sk_buff *skb)
1706{
1707	struct rfcomm_dlc *d;
1708
1709	BT_DBG("session %p state %ld dlci %d pf %d", s, s->state, dlci, pf);
1710
1711	d = rfcomm_dlc_get(s, dlci);
1712	if (!d) {
1713		rfcomm_send_dm(s, dlci);
1714		goto drop;
1715	}
1716
1717	if (pf && d->cfc) {
1718		u8 credits = *(u8 *) skb->data; skb_pull(skb, 1);
1719
1720		d->tx_credits += credits;
1721		if (d->tx_credits)
1722			clear_bit(RFCOMM_TX_THROTTLED, &d->flags);
1723	}
1724
1725	if (skb->len && d->state == BT_CONNECTED) {
1726		rfcomm_dlc_lock(d);
1727		d->rx_credits--;
1728		d->data_ready(d, skb);
1729		rfcomm_dlc_unlock(d);
1730		return 0;
1731	}
1732
1733drop:
1734	kfree_skb(skb);
1735	return 0;
1736}
1737
1738static struct rfcomm_session *rfcomm_recv_frame(struct rfcomm_session *s,
1739						struct sk_buff *skb)
1740{
1741	struct rfcomm_hdr *hdr = (void *) skb->data;
1742	u8 type, dlci, fcs;
1743
1744	if (!s) {
1745		/* no session, so free socket data */
1746		kfree_skb(skb);
1747		return s;
1748	}
1749
1750	dlci = __get_dlci(hdr->addr);
1751	type = __get_type(hdr->ctrl);
1752
1753	/* Trim FCS */
1754	skb->len--; skb->tail--;
1755	fcs = *(u8 *)skb_tail_pointer(skb);
1756
1757	if (__check_fcs(skb->data, type, fcs)) {
1758		BT_ERR("bad checksum in packet");
1759		kfree_skb(skb);
1760		return s;
1761	}
1762
1763	if (__test_ea(hdr->len))
1764		skb_pull(skb, 3);
1765	else
1766		skb_pull(skb, 4);
1767
1768	switch (type) {
1769	case RFCOMM_SABM:
1770		if (__test_pf(hdr->ctrl))
1771			rfcomm_recv_sabm(s, dlci);
1772		break;
1773
1774	case RFCOMM_DISC:
1775		if (__test_pf(hdr->ctrl))
1776			s = rfcomm_recv_disc(s, dlci);
1777		break;
1778
1779	case RFCOMM_UA:
1780		if (__test_pf(hdr->ctrl))
1781			s = rfcomm_recv_ua(s, dlci);
1782		break;
1783
1784	case RFCOMM_DM:
1785		s = rfcomm_recv_dm(s, dlci);
1786		break;
1787
1788	case RFCOMM_UIH:
1789		if (dlci) {
1790			rfcomm_recv_data(s, dlci, __test_pf(hdr->ctrl), skb);
1791			return s;
1792		}
1793		rfcomm_recv_mcc(s, skb);
1794		break;
1795
1796	default:
1797		BT_ERR("Unknown packet type 0x%02x", type);
1798		break;
1799	}
1800	kfree_skb(skb);
1801	return s;
1802}
1803
1804/* ---- Connection and data processing ---- */
1805
1806static void rfcomm_process_connect(struct rfcomm_session *s)
1807{
1808	struct rfcomm_dlc *d, *n;
1809
1810	BT_DBG("session %p state %ld", s, s->state);
1811
1812	list_for_each_entry_safe(d, n, &s->dlcs, list) {
1813		if (d->state == BT_CONFIG) {
1814			d->mtu = s->mtu;
1815			if (rfcomm_check_security(d)) {
1816				rfcomm_send_pn(s, 1, d);
1817			} else {
1818				set_bit(RFCOMM_AUTH_PENDING, &d->flags);
1819				rfcomm_dlc_set_timer(d, RFCOMM_AUTH_TIMEOUT);
1820			}
1821		}
1822	}
1823}
1824
1825/* Send data queued for the DLC.
1826 * Return number of frames left in the queue.
1827 */
1828static int rfcomm_process_tx(struct rfcomm_dlc *d)
1829{
1830	struct sk_buff *skb;
1831	int err;
1832
1833	BT_DBG("dlc %p state %ld cfc %d rx_credits %d tx_credits %d",
1834			d, d->state, d->cfc, d->rx_credits, d->tx_credits);
1835
1836	/* Send pending MSC */
1837	if (test_and_clear_bit(RFCOMM_MSC_PENDING, &d->flags))
1838		rfcomm_send_msc(d->session, 1, d->dlci, d->v24_sig);
1839
1840	if (d->cfc) {
1841		/* CFC enabled.
1842		 * Give them some credits */
1843		if (!test_bit(RFCOMM_RX_THROTTLED, &d->flags) &&
1844				d->rx_credits <= (d->cfc >> 2)) {
1845			rfcomm_send_credits(d->session, d->addr, d->cfc - d->rx_credits);
1846			d->rx_credits = d->cfc;
1847		}
1848	} else {
1849		/* CFC disabled.
1850		 * Give ourselves some credits */
1851		d->tx_credits = 5;
1852	}
1853
1854	if (test_bit(RFCOMM_TX_THROTTLED, &d->flags))
1855		return skb_queue_len(&d->tx_queue);
1856
1857	while (d->tx_credits && (skb = skb_dequeue(&d->tx_queue))) {
1858		err = rfcomm_send_frame(d->session, skb->data, skb->len);
1859		if (err < 0) {
1860			skb_queue_head(&d->tx_queue, skb);
1861			break;
1862		}
1863		kfree_skb(skb);
1864		d->tx_credits--;
1865	}
1866
1867	if (d->cfc && !d->tx_credits) {
1868		/* We're out of TX credits.
1869		 * Set TX_THROTTLED flag to avoid unnesary wakeups by dlc_send. */
1870		set_bit(RFCOMM_TX_THROTTLED, &d->flags);
1871	}
1872
1873	return skb_queue_len(&d->tx_queue);
1874}
1875
1876static void rfcomm_process_dlcs(struct rfcomm_session *s)
1877{
1878	struct rfcomm_dlc *d, *n;
1879
1880	BT_DBG("session %p state %ld", s, s->state);
1881
1882	list_for_each_entry_safe(d, n, &s->dlcs, list) {
1883		if (test_bit(RFCOMM_TIMED_OUT, &d->flags)) {
1884			__rfcomm_dlc_close(d, ETIMEDOUT);
1885			continue;
1886		}
1887
1888		if (test_bit(RFCOMM_ENC_DROP, &d->flags)) {
1889			__rfcomm_dlc_close(d, ECONNREFUSED);
1890			continue;
1891		}
1892
1893		if (test_and_clear_bit(RFCOMM_AUTH_ACCEPT, &d->flags)) {
1894			rfcomm_dlc_clear_timer(d);
1895			if (d->out) {
1896				rfcomm_send_pn(s, 1, d);
1897				rfcomm_dlc_set_timer(d, RFCOMM_CONN_TIMEOUT);
1898			} else {
1899				if (d->defer_setup) {
1900					set_bit(RFCOMM_DEFER_SETUP, &d->flags);
1901					rfcomm_dlc_set_timer(d, RFCOMM_AUTH_TIMEOUT);
1902
1903					rfcomm_dlc_lock(d);
1904					d->state = BT_CONNECT2;
1905					d->state_change(d, 0);
1906					rfcomm_dlc_unlock(d);
1907				} else
1908					rfcomm_dlc_accept(d);
1909			}
1910			continue;
1911		} else if (test_and_clear_bit(RFCOMM_AUTH_REJECT, &d->flags)) {
1912			rfcomm_dlc_clear_timer(d);
1913			if (!d->out)
1914				rfcomm_send_dm(s, d->dlci);
1915			else
1916				d->state = BT_CLOSED;
1917			__rfcomm_dlc_close(d, ECONNREFUSED);
1918			continue;
1919		}
1920
1921		if (test_bit(RFCOMM_SEC_PENDING, &d->flags))
1922			continue;
1923
1924		if (test_bit(RFCOMM_TX_THROTTLED, &s->flags))
1925			continue;
1926
1927		if ((d->state == BT_CONNECTED || d->state == BT_DISCONN) &&
1928						d->mscex == RFCOMM_MSCEX_OK)
1929			rfcomm_process_tx(d);
1930	}
1931}
1932
1933static struct rfcomm_session *rfcomm_process_rx(struct rfcomm_session *s)
1934{
1935	struct socket *sock = s->sock;
1936	struct sock *sk = sock->sk;
1937	struct sk_buff *skb;
1938
1939	BT_DBG("session %p state %ld qlen %d", s, s->state, skb_queue_len(&sk->sk_receive_queue));
1940
1941	/* Get data directly from socket receive queue without copying it. */
1942	while ((skb = skb_dequeue(&sk->sk_receive_queue))) {
1943		skb_orphan(skb);
1944		if (!skb_linearize(skb) && sk->sk_state != BT_CLOSED) {
1945			s = rfcomm_recv_frame(s, skb);
1946			if (!s)
1947				break;
1948		} else {
1949			kfree_skb(skb);
1950		}
1951	}
1952
1953	if (s && (sk->sk_state == BT_CLOSED))
1954		s = rfcomm_session_close(s, sk->sk_err);
1955
1956	return s;
1957}
1958
1959static void rfcomm_accept_connection(struct rfcomm_session *s)
1960{
1961	struct socket *sock = s->sock, *nsock;
1962	int err;
1963
1964	/* Fast check for a new connection.
1965	 * Avoids unnesesary socket allocations. */
1966	if (list_empty(&bt_sk(sock->sk)->accept_q))
1967		return;
1968
1969	BT_DBG("session %p", s);
1970
1971	err = kernel_accept(sock, &nsock, O_NONBLOCK);
1972	if (err < 0)
1973		return;
1974
1975	/* Set our callbacks */
1976	nsock->sk->sk_data_ready   = rfcomm_l2data_ready;
1977	nsock->sk->sk_state_change = rfcomm_l2state_change;
1978
1979	s = rfcomm_session_add(nsock, BT_OPEN);
1980	if (s) {
1981		/* We should adjust MTU on incoming sessions.
1982		 * L2CAP MTU minus UIH header and FCS. */
1983		s->mtu = min(l2cap_pi(nsock->sk)->chan->omtu,
1984				l2cap_pi(nsock->sk)->chan->imtu) - 5;
1985
1986		rfcomm_schedule();
1987	} else
1988		sock_release(nsock);
1989}
1990
1991static struct rfcomm_session *rfcomm_check_connection(struct rfcomm_session *s)
1992{
1993	struct sock *sk = s->sock->sk;
1994
1995	BT_DBG("%p state %ld", s, s->state);
1996
1997	switch (sk->sk_state) {
1998	case BT_CONNECTED:
1999		s->state = BT_CONNECT;
2000
2001		/* We can adjust MTU on outgoing sessions.
2002		 * L2CAP MTU minus UIH header and FCS. */
2003		s->mtu = min(l2cap_pi(sk)->chan->omtu, l2cap_pi(sk)->chan->imtu) - 5;
2004
2005		rfcomm_send_sabm(s, 0);
2006		break;
2007
2008	case BT_CLOSED:
2009		s = rfcomm_session_close(s, sk->sk_err);
2010		break;
2011	}
2012	return s;
2013}
2014
2015static void rfcomm_process_sessions(void)
2016{
2017	struct rfcomm_session *s, *n;
2018
2019	rfcomm_lock();
2020
2021	list_for_each_entry_safe(s, n, &session_list, list) {
2022		if (test_and_clear_bit(RFCOMM_TIMED_OUT, &s->flags)) {
2023			s->state = BT_DISCONN;
2024			rfcomm_send_disc(s, 0);
2025			continue;
2026		}
2027
2028		switch (s->state) {
2029		case BT_LISTEN:
2030			rfcomm_accept_connection(s);
2031			continue;
2032
2033		case BT_BOUND:
2034			s = rfcomm_check_connection(s);
2035			break;
2036
2037		default:
2038			s = rfcomm_process_rx(s);
2039			break;
2040		}
2041
2042		if (s)
2043			rfcomm_process_dlcs(s);
2044	}
2045
2046	rfcomm_unlock();
2047}
2048
2049static int rfcomm_add_listener(bdaddr_t *ba)
2050{
2051	struct sockaddr_l2 addr;
2052	struct socket *sock;
2053	struct sock *sk;
2054	struct rfcomm_session *s;
2055	int    err = 0;
2056
2057	/* Create socket */
2058	err = rfcomm_l2sock_create(&sock);
2059	if (err < 0) {
2060		BT_ERR("Create socket failed %d", err);
2061		return err;
2062	}
2063
2064	/* Bind socket */
2065	bacpy(&addr.l2_bdaddr, ba);
2066	addr.l2_family = AF_BLUETOOTH;
2067	addr.l2_psm    = cpu_to_le16(L2CAP_PSM_RFCOMM);
2068	addr.l2_cid    = 0;
2069	addr.l2_bdaddr_type = BDADDR_BREDR;
2070	err = kernel_bind(sock, (struct sockaddr *) &addr, sizeof(addr));
2071	if (err < 0) {
2072		BT_ERR("Bind failed %d", err);
2073		goto failed;
2074	}
2075
2076	/* Set L2CAP options */
2077	sk = sock->sk;
2078	lock_sock(sk);
2079	/* Set MTU to 0 so L2CAP can auto select the MTU */
2080	l2cap_pi(sk)->chan->imtu = 0;
2081	release_sock(sk);
2082
2083	/* Start listening on the socket */
2084	err = kernel_listen(sock, 10);
2085	if (err) {
2086		BT_ERR("Listen failed %d", err);
2087		goto failed;
2088	}
2089
2090	/* Add listening session */
2091	s = rfcomm_session_add(sock, BT_LISTEN);
2092	if (!s) {
2093		err = -ENOMEM;
2094		goto failed;
2095	}
2096
2097	return 0;
2098failed:
2099	sock_release(sock);
2100	return err;
2101}
2102
2103static void rfcomm_kill_listener(void)
2104{
2105	struct rfcomm_session *s, *n;
2106
2107	BT_DBG("");
2108
2109	list_for_each_entry_safe(s, n, &session_list, list)
2110		rfcomm_session_del(s);
2111}
2112
2113static int rfcomm_run(void *unused)
2114{
2115	DEFINE_WAIT_FUNC(wait, woken_wake_function);
2116	BT_DBG("");
2117
2118	set_user_nice(current, -10);
2119
2120	rfcomm_add_listener(BDADDR_ANY);
2121
2122	add_wait_queue(&rfcomm_wq, &wait);
2123	while (!kthread_should_stop()) {
2124
2125		/* Process stuff */
2126		rfcomm_process_sessions();
2127
2128		wait_woken(&wait, TASK_INTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT);
2129	}
2130	remove_wait_queue(&rfcomm_wq, &wait);
2131
2132	rfcomm_kill_listener();
2133
2134	return 0;
2135}
2136
2137static void rfcomm_security_cfm(struct hci_conn *conn, u8 status, u8 encrypt)
2138{
2139	struct rfcomm_session *s;
2140	struct rfcomm_dlc *d, *n;
2141
2142	BT_DBG("conn %p status 0x%02x encrypt 0x%02x", conn, status, encrypt);
2143
2144	s = rfcomm_session_get(&conn->hdev->bdaddr, &conn->dst);
2145	if (!s)
2146		return;
2147
2148	list_for_each_entry_safe(d, n, &s->dlcs, list) {
2149		if (test_and_clear_bit(RFCOMM_SEC_PENDING, &d->flags)) {
2150			rfcomm_dlc_clear_timer(d);
2151			if (status || encrypt == 0x00) {
2152				set_bit(RFCOMM_ENC_DROP, &d->flags);
2153				continue;
2154			}
2155		}
2156
2157		if (d->state == BT_CONNECTED && !status && encrypt == 0x00) {
2158			if (d->sec_level == BT_SECURITY_MEDIUM) {
2159				set_bit(RFCOMM_SEC_PENDING, &d->flags);
2160				rfcomm_dlc_set_timer(d, RFCOMM_AUTH_TIMEOUT);
2161				continue;
2162			} else if (d->sec_level == BT_SECURITY_HIGH ||
2163				   d->sec_level == BT_SECURITY_FIPS) {
2164				set_bit(RFCOMM_ENC_DROP, &d->flags);
2165				continue;
2166			}
2167		}
2168
2169		if (!test_and_clear_bit(RFCOMM_AUTH_PENDING, &d->flags))
2170			continue;
2171
2172		if (!status && hci_conn_check_secure(conn, d->sec_level))
2173			set_bit(RFCOMM_AUTH_ACCEPT, &d->flags);
2174		else
2175			set_bit(RFCOMM_AUTH_REJECT, &d->flags);
2176	}
2177
2178	rfcomm_schedule();
2179}
2180
2181static struct hci_cb rfcomm_cb = {
2182	.name		= "RFCOMM",
2183	.security_cfm	= rfcomm_security_cfm
2184};
2185
2186static int rfcomm_dlc_debugfs_show(struct seq_file *f, void *x)
2187{
2188	struct rfcomm_session *s;
2189
2190	rfcomm_lock();
2191
2192	list_for_each_entry(s, &session_list, list) {
2193		struct l2cap_chan *chan = l2cap_pi(s->sock->sk)->chan;
2194		struct rfcomm_dlc *d;
2195		list_for_each_entry(d, &s->dlcs, list) {
2196			seq_printf(f, "%pMR %pMR %ld %d %d %d %d\n",
2197				   &chan->src, &chan->dst,
2198				   d->state, d->dlci, d->mtu,
2199				   d->rx_credits, d->tx_credits);
2200		}
2201	}
2202
2203	rfcomm_unlock();
2204
2205	return 0;
2206}
2207
2208DEFINE_SHOW_ATTRIBUTE(rfcomm_dlc_debugfs);
2209
2210static struct dentry *rfcomm_dlc_debugfs;
2211
2212/* ---- Initialization ---- */
2213static int __init rfcomm_init(void)
2214{
2215	int err;
2216
2217	hci_register_cb(&rfcomm_cb);
2218
2219	rfcomm_thread = kthread_run(rfcomm_run, NULL, "krfcommd");
2220	if (IS_ERR(rfcomm_thread)) {
2221		err = PTR_ERR(rfcomm_thread);
2222		goto unregister;
2223	}
2224
2225	err = rfcomm_init_ttys();
2226	if (err < 0)
2227		goto stop;
2228
2229	err = rfcomm_init_sockets();
2230	if (err < 0)
2231		goto cleanup;
2232
2233	BT_INFO("RFCOMM ver %s", VERSION);
2234
2235	if (IS_ERR_OR_NULL(bt_debugfs))
2236		return 0;
2237
2238	rfcomm_dlc_debugfs = debugfs_create_file("rfcomm_dlc", 0444,
2239						 bt_debugfs, NULL,
2240						 &rfcomm_dlc_debugfs_fops);
2241
2242	return 0;
2243
2244cleanup:
2245	rfcomm_cleanup_ttys();
2246
2247stop:
2248	kthread_stop(rfcomm_thread);
2249
2250unregister:
2251	hci_unregister_cb(&rfcomm_cb);
2252
2253	return err;
2254}
2255
2256static void __exit rfcomm_exit(void)
2257{
2258	debugfs_remove(rfcomm_dlc_debugfs);
2259
2260	hci_unregister_cb(&rfcomm_cb);
2261
2262	kthread_stop(rfcomm_thread);
2263
2264	rfcomm_cleanup_ttys();
2265
2266	rfcomm_cleanup_sockets();
2267}
2268
2269module_init(rfcomm_init);
2270module_exit(rfcomm_exit);
2271
2272module_param(disable_cfc, bool, 0644);
2273MODULE_PARM_DESC(disable_cfc, "Disable credit based flow control");
2274
2275module_param(channel_mtu, int, 0644);
2276MODULE_PARM_DESC(channel_mtu, "Default MTU for the RFCOMM channel");
2277
2278module_param(l2cap_ertm, bool, 0644);
2279MODULE_PARM_DESC(l2cap_ertm, "Use L2CAP ERTM mode for connection");
2280
2281MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>");
2282MODULE_DESCRIPTION("Bluetooth RFCOMM ver " VERSION);
2283MODULE_VERSION(VERSION);
2284MODULE_LICENSE("GPL");
2285MODULE_ALIAS("bt-proto-3");
v6.2
   1/*
   2   RFCOMM implementation for Linux Bluetooth stack (BlueZ).
   3   Copyright (C) 2002 Maxim Krasnyansky <maxk@qualcomm.com>
   4   Copyright (C) 2002 Marcel Holtmann <marcel@holtmann.org>
   5
   6   This program is free software; you can redistribute it and/or modify
   7   it under the terms of the GNU General Public License version 2 as
   8   published by the Free Software Foundation;
   9
  10   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  11   OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  12   FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS.
  13   IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) AND AUTHOR(S) BE LIABLE FOR ANY
  14   CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES
  15   WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  16   ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  17   OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  18
  19   ALL LIABILITY, INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PATENTS,
  20   COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS, RELATING TO USE OF THIS
  21   SOFTWARE IS DISCLAIMED.
  22*/
  23
  24/*
  25 * Bluetooth RFCOMM core.
  26 */
  27
  28#include <linux/module.h>
  29#include <linux/debugfs.h>
  30#include <linux/kthread.h>
  31#include <asm/unaligned.h>
  32
  33#include <net/bluetooth/bluetooth.h>
  34#include <net/bluetooth/hci_core.h>
  35#include <net/bluetooth/l2cap.h>
  36#include <net/bluetooth/rfcomm.h>
  37
 
 
  38#define VERSION "1.11"
  39
  40static bool disable_cfc;
  41static bool l2cap_ertm;
  42static int channel_mtu = -1;
  43
  44static struct task_struct *rfcomm_thread;
  45
  46static DEFINE_MUTEX(rfcomm_mutex);
  47#define rfcomm_lock()	mutex_lock(&rfcomm_mutex)
  48#define rfcomm_unlock()	mutex_unlock(&rfcomm_mutex)
  49
  50
  51static LIST_HEAD(session_list);
  52
  53static int rfcomm_send_frame(struct rfcomm_session *s, u8 *data, int len);
  54static int rfcomm_send_sabm(struct rfcomm_session *s, u8 dlci);
  55static int rfcomm_send_disc(struct rfcomm_session *s, u8 dlci);
  56static int rfcomm_queue_disc(struct rfcomm_dlc *d);
  57static int rfcomm_send_nsc(struct rfcomm_session *s, int cr, u8 type);
  58static int rfcomm_send_pn(struct rfcomm_session *s, int cr, struct rfcomm_dlc *d);
  59static int rfcomm_send_msc(struct rfcomm_session *s, int cr, u8 dlci, u8 v24_sig);
  60static int rfcomm_send_test(struct rfcomm_session *s, int cr, u8 *pattern, int len);
  61static int rfcomm_send_credits(struct rfcomm_session *s, u8 addr, u8 credits);
  62static void rfcomm_make_uih(struct sk_buff *skb, u8 addr);
  63
  64static void rfcomm_process_connect(struct rfcomm_session *s);
  65
  66static struct rfcomm_session *rfcomm_session_create(bdaddr_t *src,
  67							bdaddr_t *dst,
  68							u8 sec_level,
  69							int *err);
  70static struct rfcomm_session *rfcomm_session_get(bdaddr_t *src, bdaddr_t *dst);
  71static struct rfcomm_session *rfcomm_session_del(struct rfcomm_session *s);
  72
  73/* ---- RFCOMM frame parsing macros ---- */
  74#define __get_dlci(b)     ((b & 0xfc) >> 2)
  75#define __get_type(b)     ((b & 0xef))
  76
  77#define __test_ea(b)      ((b & 0x01))
  78#define __test_cr(b)      (!!(b & 0x02))
  79#define __test_pf(b)      (!!(b & 0x10))
  80
  81#define __session_dir(s)  ((s)->initiator ? 0x00 : 0x01)
  82
  83#define __addr(cr, dlci)       (((dlci & 0x3f) << 2) | (cr << 1) | 0x01)
  84#define __ctrl(type, pf)       (((type & 0xef) | (pf << 4)))
  85#define __dlci(dir, chn)       (((chn & 0x1f) << 1) | dir)
  86#define __srv_channel(dlci)    (dlci >> 1)
  87
  88#define __len8(len)       (((len) << 1) | 1)
  89#define __len16(len)      ((len) << 1)
  90
  91/* MCC macros */
  92#define __mcc_type(cr, type)   (((type << 2) | (cr << 1) | 0x01))
  93#define __get_mcc_type(b) ((b & 0xfc) >> 2)
  94#define __get_mcc_len(b)  ((b & 0xfe) >> 1)
  95
  96/* RPN macros */
  97#define __rpn_line_settings(data, stop, parity)  ((data & 0x3) | ((stop & 0x1) << 2) | ((parity & 0x7) << 3))
  98#define __get_rpn_data_bits(line) ((line) & 0x3)
  99#define __get_rpn_stop_bits(line) (((line) >> 2) & 0x1)
 100#define __get_rpn_parity(line)    (((line) >> 3) & 0x7)
 101
 102static DECLARE_WAIT_QUEUE_HEAD(rfcomm_wq);
 103
 104static void rfcomm_schedule(void)
 105{
 106	wake_up_all(&rfcomm_wq);
 107}
 108
 109/* ---- RFCOMM FCS computation ---- */
 110
 111/* reversed, 8-bit, poly=0x07 */
 112static unsigned char rfcomm_crc_table[256] = {
 113	0x00, 0x91, 0xe3, 0x72, 0x07, 0x96, 0xe4, 0x75,
 114	0x0e, 0x9f, 0xed, 0x7c, 0x09, 0x98, 0xea, 0x7b,
 115	0x1c, 0x8d, 0xff, 0x6e, 0x1b, 0x8a, 0xf8, 0x69,
 116	0x12, 0x83, 0xf1, 0x60, 0x15, 0x84, 0xf6, 0x67,
 117
 118	0x38, 0xa9, 0xdb, 0x4a, 0x3f, 0xae, 0xdc, 0x4d,
 119	0x36, 0xa7, 0xd5, 0x44, 0x31, 0xa0, 0xd2, 0x43,
 120	0x24, 0xb5, 0xc7, 0x56, 0x23, 0xb2, 0xc0, 0x51,
 121	0x2a, 0xbb, 0xc9, 0x58, 0x2d, 0xbc, 0xce, 0x5f,
 122
 123	0x70, 0xe1, 0x93, 0x02, 0x77, 0xe6, 0x94, 0x05,
 124	0x7e, 0xef, 0x9d, 0x0c, 0x79, 0xe8, 0x9a, 0x0b,
 125	0x6c, 0xfd, 0x8f, 0x1e, 0x6b, 0xfa, 0x88, 0x19,
 126	0x62, 0xf3, 0x81, 0x10, 0x65, 0xf4, 0x86, 0x17,
 127
 128	0x48, 0xd9, 0xab, 0x3a, 0x4f, 0xde, 0xac, 0x3d,
 129	0x46, 0xd7, 0xa5, 0x34, 0x41, 0xd0, 0xa2, 0x33,
 130	0x54, 0xc5, 0xb7, 0x26, 0x53, 0xc2, 0xb0, 0x21,
 131	0x5a, 0xcb, 0xb9, 0x28, 0x5d, 0xcc, 0xbe, 0x2f,
 132
 133	0xe0, 0x71, 0x03, 0x92, 0xe7, 0x76, 0x04, 0x95,
 134	0xee, 0x7f, 0x0d, 0x9c, 0xe9, 0x78, 0x0a, 0x9b,
 135	0xfc, 0x6d, 0x1f, 0x8e, 0xfb, 0x6a, 0x18, 0x89,
 136	0xf2, 0x63, 0x11, 0x80, 0xf5, 0x64, 0x16, 0x87,
 137
 138	0xd8, 0x49, 0x3b, 0xaa, 0xdf, 0x4e, 0x3c, 0xad,
 139	0xd6, 0x47, 0x35, 0xa4, 0xd1, 0x40, 0x32, 0xa3,
 140	0xc4, 0x55, 0x27, 0xb6, 0xc3, 0x52, 0x20, 0xb1,
 141	0xca, 0x5b, 0x29, 0xb8, 0xcd, 0x5c, 0x2e, 0xbf,
 142
 143	0x90, 0x01, 0x73, 0xe2, 0x97, 0x06, 0x74, 0xe5,
 144	0x9e, 0x0f, 0x7d, 0xec, 0x99, 0x08, 0x7a, 0xeb,
 145	0x8c, 0x1d, 0x6f, 0xfe, 0x8b, 0x1a, 0x68, 0xf9,
 146	0x82, 0x13, 0x61, 0xf0, 0x85, 0x14, 0x66, 0xf7,
 147
 148	0xa8, 0x39, 0x4b, 0xda, 0xaf, 0x3e, 0x4c, 0xdd,
 149	0xa6, 0x37, 0x45, 0xd4, 0xa1, 0x30, 0x42, 0xd3,
 150	0xb4, 0x25, 0x57, 0xc6, 0xb3, 0x22, 0x50, 0xc1,
 151	0xba, 0x2b, 0x59, 0xc8, 0xbd, 0x2c, 0x5e, 0xcf
 152};
 153
 154/* CRC on 2 bytes */
 155#define __crc(data) (rfcomm_crc_table[rfcomm_crc_table[0xff ^ data[0]] ^ data[1]])
 156
 157/* FCS on 2 bytes */
 158static inline u8 __fcs(u8 *data)
 159{
 160	return 0xff - __crc(data);
 161}
 162
 163/* FCS on 3 bytes */
 164static inline u8 __fcs2(u8 *data)
 165{
 166	return 0xff - rfcomm_crc_table[__crc(data) ^ data[2]];
 167}
 168
 169/* Check FCS */
 170static inline int __check_fcs(u8 *data, int type, u8 fcs)
 171{
 172	u8 f = __crc(data);
 173
 174	if (type != RFCOMM_UIH)
 175		f = rfcomm_crc_table[f ^ data[2]];
 176
 177	return rfcomm_crc_table[f ^ fcs] != 0xcf;
 178}
 179
 180/* ---- L2CAP callbacks ---- */
 181static void rfcomm_l2state_change(struct sock *sk)
 182{
 183	BT_DBG("%p state %d", sk, sk->sk_state);
 184	rfcomm_schedule();
 185}
 186
 187static void rfcomm_l2data_ready(struct sock *sk)
 188{
 
 
 189	BT_DBG("%p", sk);
 190	rfcomm_schedule();
 191}
 192
 193static int rfcomm_l2sock_create(struct socket **sock)
 194{
 195	int err;
 196
 197	BT_DBG("");
 198
 199	err = sock_create_kern(&init_net, PF_BLUETOOTH, SOCK_SEQPACKET, BTPROTO_L2CAP, sock);
 200	if (!err) {
 201		struct sock *sk = (*sock)->sk;
 202		sk->sk_data_ready   = rfcomm_l2data_ready;
 203		sk->sk_state_change = rfcomm_l2state_change;
 204	}
 205	return err;
 206}
 207
 208static int rfcomm_check_security(struct rfcomm_dlc *d)
 209{
 210	struct sock *sk = d->session->sock->sk;
 211	struct l2cap_conn *conn = l2cap_pi(sk)->chan->conn;
 212
 213	__u8 auth_type;
 214
 215	switch (d->sec_level) {
 216	case BT_SECURITY_HIGH:
 217	case BT_SECURITY_FIPS:
 218		auth_type = HCI_AT_GENERAL_BONDING_MITM;
 219		break;
 220	case BT_SECURITY_MEDIUM:
 221		auth_type = HCI_AT_GENERAL_BONDING;
 222		break;
 223	default:
 224		auth_type = HCI_AT_NO_BONDING;
 225		break;
 226	}
 227
 228	return hci_conn_security(conn->hcon, d->sec_level, auth_type,
 229				 d->out);
 230}
 231
 232static void rfcomm_session_timeout(struct timer_list *t)
 233{
 234	struct rfcomm_session *s = from_timer(s, t, timer);
 235
 236	BT_DBG("session %p state %ld", s, s->state);
 237
 238	set_bit(RFCOMM_TIMED_OUT, &s->flags);
 239	rfcomm_schedule();
 240}
 241
 242static void rfcomm_session_set_timer(struct rfcomm_session *s, long timeout)
 243{
 244	BT_DBG("session %p state %ld timeout %ld", s, s->state, timeout);
 245
 246	mod_timer(&s->timer, jiffies + timeout);
 247}
 248
 249static void rfcomm_session_clear_timer(struct rfcomm_session *s)
 250{
 251	BT_DBG("session %p state %ld", s, s->state);
 252
 253	del_timer_sync(&s->timer);
 254}
 255
 256/* ---- RFCOMM DLCs ---- */
 257static void rfcomm_dlc_timeout(struct timer_list *t)
 258{
 259	struct rfcomm_dlc *d = from_timer(d, t, timer);
 260
 261	BT_DBG("dlc %p state %ld", d, d->state);
 262
 263	set_bit(RFCOMM_TIMED_OUT, &d->flags);
 264	rfcomm_dlc_put(d);
 265	rfcomm_schedule();
 266}
 267
 268static void rfcomm_dlc_set_timer(struct rfcomm_dlc *d, long timeout)
 269{
 270	BT_DBG("dlc %p state %ld timeout %ld", d, d->state, timeout);
 271
 272	if (!mod_timer(&d->timer, jiffies + timeout))
 273		rfcomm_dlc_hold(d);
 274}
 275
 276static void rfcomm_dlc_clear_timer(struct rfcomm_dlc *d)
 277{
 278	BT_DBG("dlc %p state %ld", d, d->state);
 279
 280	if (del_timer(&d->timer))
 281		rfcomm_dlc_put(d);
 282}
 283
 284static void rfcomm_dlc_clear_state(struct rfcomm_dlc *d)
 285{
 286	BT_DBG("%p", d);
 287
 288	d->state      = BT_OPEN;
 289	d->flags      = 0;
 290	d->mscex      = 0;
 291	d->sec_level  = BT_SECURITY_LOW;
 292	d->mtu        = RFCOMM_DEFAULT_MTU;
 293	d->v24_sig    = RFCOMM_V24_RTC | RFCOMM_V24_RTR | RFCOMM_V24_DV;
 294
 295	d->cfc        = RFCOMM_CFC_DISABLED;
 296	d->rx_credits = RFCOMM_DEFAULT_CREDITS;
 297}
 298
 299struct rfcomm_dlc *rfcomm_dlc_alloc(gfp_t prio)
 300{
 301	struct rfcomm_dlc *d = kzalloc(sizeof(*d), prio);
 302
 303	if (!d)
 304		return NULL;
 305
 306	timer_setup(&d->timer, rfcomm_dlc_timeout, 0);
 307
 308	skb_queue_head_init(&d->tx_queue);
 309	mutex_init(&d->lock);
 310	refcount_set(&d->refcnt, 1);
 311
 312	rfcomm_dlc_clear_state(d);
 313
 314	BT_DBG("%p", d);
 315
 316	return d;
 317}
 318
 319void rfcomm_dlc_free(struct rfcomm_dlc *d)
 320{
 321	BT_DBG("%p", d);
 322
 323	skb_queue_purge(&d->tx_queue);
 324	kfree(d);
 325}
 326
 327static void rfcomm_dlc_link(struct rfcomm_session *s, struct rfcomm_dlc *d)
 328{
 329	BT_DBG("dlc %p session %p", d, s);
 330
 331	rfcomm_session_clear_timer(s);
 332	rfcomm_dlc_hold(d);
 333	list_add(&d->list, &s->dlcs);
 334	d->session = s;
 335}
 336
 337static void rfcomm_dlc_unlink(struct rfcomm_dlc *d)
 338{
 339	struct rfcomm_session *s = d->session;
 340
 341	BT_DBG("dlc %p refcnt %d session %p", d, refcount_read(&d->refcnt), s);
 342
 343	list_del(&d->list);
 344	d->session = NULL;
 345	rfcomm_dlc_put(d);
 346
 347	if (list_empty(&s->dlcs))
 348		rfcomm_session_set_timer(s, RFCOMM_IDLE_TIMEOUT);
 349}
 350
 351static struct rfcomm_dlc *rfcomm_dlc_get(struct rfcomm_session *s, u8 dlci)
 352{
 353	struct rfcomm_dlc *d;
 354
 355	list_for_each_entry(d, &s->dlcs, list)
 356		if (d->dlci == dlci)
 357			return d;
 358
 359	return NULL;
 360}
 361
 362static int rfcomm_check_channel(u8 channel)
 363{
 364	return channel < 1 || channel > 30;
 365}
 366
 367static int __rfcomm_dlc_open(struct rfcomm_dlc *d, bdaddr_t *src, bdaddr_t *dst, u8 channel)
 368{
 369	struct rfcomm_session *s;
 370	int err = 0;
 371	u8 dlci;
 372
 373	BT_DBG("dlc %p state %ld %pMR -> %pMR channel %d",
 374	       d, d->state, src, dst, channel);
 375
 376	if (rfcomm_check_channel(channel))
 377		return -EINVAL;
 378
 379	if (d->state != BT_OPEN && d->state != BT_CLOSED)
 380		return 0;
 381
 382	s = rfcomm_session_get(src, dst);
 383	if (!s) {
 384		s = rfcomm_session_create(src, dst, d->sec_level, &err);
 385		if (!s)
 386			return err;
 387	}
 388
 389	dlci = __dlci(__session_dir(s), channel);
 390
 391	/* Check if DLCI already exists */
 392	if (rfcomm_dlc_get(s, dlci))
 393		return -EBUSY;
 394
 395	rfcomm_dlc_clear_state(d);
 396
 397	d->dlci     = dlci;
 398	d->addr     = __addr(s->initiator, dlci);
 399	d->priority = 7;
 400
 401	d->state = BT_CONFIG;
 402	rfcomm_dlc_link(s, d);
 403
 404	d->out = 1;
 405
 406	d->mtu = s->mtu;
 407	d->cfc = (s->cfc == RFCOMM_CFC_UNKNOWN) ? 0 : s->cfc;
 408
 409	if (s->state == BT_CONNECTED) {
 410		if (rfcomm_check_security(d))
 411			rfcomm_send_pn(s, 1, d);
 412		else
 413			set_bit(RFCOMM_AUTH_PENDING, &d->flags);
 414	}
 415
 416	rfcomm_dlc_set_timer(d, RFCOMM_CONN_TIMEOUT);
 417
 418	return 0;
 419}
 420
 421int rfcomm_dlc_open(struct rfcomm_dlc *d, bdaddr_t *src, bdaddr_t *dst, u8 channel)
 422{
 423	int r;
 424
 425	rfcomm_lock();
 426
 427	r = __rfcomm_dlc_open(d, src, dst, channel);
 428
 429	rfcomm_unlock();
 430	return r;
 431}
 432
 433static void __rfcomm_dlc_disconn(struct rfcomm_dlc *d)
 434{
 435	struct rfcomm_session *s = d->session;
 436
 437	d->state = BT_DISCONN;
 438	if (skb_queue_empty(&d->tx_queue)) {
 439		rfcomm_send_disc(s, d->dlci);
 440		rfcomm_dlc_set_timer(d, RFCOMM_DISC_TIMEOUT);
 441	} else {
 442		rfcomm_queue_disc(d);
 443		rfcomm_dlc_set_timer(d, RFCOMM_DISC_TIMEOUT * 2);
 444	}
 445}
 446
 447static int __rfcomm_dlc_close(struct rfcomm_dlc *d, int err)
 448{
 449	struct rfcomm_session *s = d->session;
 450	if (!s)
 451		return 0;
 452
 453	BT_DBG("dlc %p state %ld dlci %d err %d session %p",
 454			d, d->state, d->dlci, err, s);
 455
 456	switch (d->state) {
 457	case BT_CONNECT:
 458	case BT_CONFIG:
 459	case BT_OPEN:
 460	case BT_CONNECT2:
 461		if (test_and_clear_bit(RFCOMM_DEFER_SETUP, &d->flags)) {
 462			set_bit(RFCOMM_AUTH_REJECT, &d->flags);
 463			rfcomm_schedule();
 464			return 0;
 465		}
 466	}
 467
 468	switch (d->state) {
 469	case BT_CONNECT:
 470	case BT_CONNECTED:
 471		__rfcomm_dlc_disconn(d);
 472		break;
 473
 474	case BT_CONFIG:
 475		if (s->state != BT_BOUND) {
 476			__rfcomm_dlc_disconn(d);
 477			break;
 478		}
 479		/* if closing a dlc in a session that hasn't been started,
 480		 * just close and unlink the dlc
 481		 */
 482		fallthrough;
 483
 484	default:
 485		rfcomm_dlc_clear_timer(d);
 486
 487		rfcomm_dlc_lock(d);
 488		d->state = BT_CLOSED;
 489		d->state_change(d, err);
 490		rfcomm_dlc_unlock(d);
 491
 492		skb_queue_purge(&d->tx_queue);
 493		rfcomm_dlc_unlink(d);
 494	}
 495
 496	return 0;
 497}
 498
 499int rfcomm_dlc_close(struct rfcomm_dlc *d, int err)
 500{
 501	int r = 0;
 502	struct rfcomm_dlc *d_list;
 503	struct rfcomm_session *s, *s_list;
 504
 505	BT_DBG("dlc %p state %ld dlci %d err %d", d, d->state, d->dlci, err);
 506
 507	rfcomm_lock();
 508
 509	s = d->session;
 510	if (!s)
 511		goto no_session;
 512
 513	/* after waiting on the mutex check the session still exists
 514	 * then check the dlc still exists
 515	 */
 516	list_for_each_entry(s_list, &session_list, list) {
 517		if (s_list == s) {
 518			list_for_each_entry(d_list, &s->dlcs, list) {
 519				if (d_list == d) {
 520					r = __rfcomm_dlc_close(d, err);
 521					break;
 522				}
 523			}
 524			break;
 525		}
 526	}
 527
 528no_session:
 529	rfcomm_unlock();
 530	return r;
 531}
 532
 533struct rfcomm_dlc *rfcomm_dlc_exists(bdaddr_t *src, bdaddr_t *dst, u8 channel)
 534{
 535	struct rfcomm_session *s;
 536	struct rfcomm_dlc *dlc = NULL;
 537	u8 dlci;
 538
 539	if (rfcomm_check_channel(channel))
 540		return ERR_PTR(-EINVAL);
 541
 542	rfcomm_lock();
 543	s = rfcomm_session_get(src, dst);
 544	if (s) {
 545		dlci = __dlci(__session_dir(s), channel);
 546		dlc = rfcomm_dlc_get(s, dlci);
 547	}
 548	rfcomm_unlock();
 549	return dlc;
 550}
 551
 552static int rfcomm_dlc_send_frag(struct rfcomm_dlc *d, struct sk_buff *frag)
 553{
 554	int len = frag->len;
 555
 556	BT_DBG("dlc %p mtu %d len %d", d, d->mtu, len);
 557
 558	if (len > d->mtu)
 559		return -EINVAL;
 560
 561	rfcomm_make_uih(frag, d->addr);
 562	__skb_queue_tail(&d->tx_queue, frag);
 563
 564	return len;
 565}
 566
 567int rfcomm_dlc_send(struct rfcomm_dlc *d, struct sk_buff *skb)
 568{
 569	unsigned long flags;
 570	struct sk_buff *frag, *next;
 571	int len;
 572
 573	if (d->state != BT_CONNECTED)
 574		return -ENOTCONN;
 575
 576	frag = skb_shinfo(skb)->frag_list;
 577	skb_shinfo(skb)->frag_list = NULL;
 578
 579	/* Queue all fragments atomically. */
 580	spin_lock_irqsave(&d->tx_queue.lock, flags);
 581
 582	len = rfcomm_dlc_send_frag(d, skb);
 583	if (len < 0 || !frag)
 584		goto unlock;
 585
 586	for (; frag; frag = next) {
 587		int ret;
 588
 589		next = frag->next;
 590
 591		ret = rfcomm_dlc_send_frag(d, frag);
 592		if (ret < 0) {
 593			dev_kfree_skb_irq(frag);
 594			goto unlock;
 595		}
 596
 597		len += ret;
 598	}
 599
 600unlock:
 601	spin_unlock_irqrestore(&d->tx_queue.lock, flags);
 602
 603	if (len > 0 && !test_bit(RFCOMM_TX_THROTTLED, &d->flags))
 604		rfcomm_schedule();
 605	return len;
 606}
 607
 608void rfcomm_dlc_send_noerror(struct rfcomm_dlc *d, struct sk_buff *skb)
 609{
 610	int len = skb->len;
 611
 612	BT_DBG("dlc %p mtu %d len %d", d, d->mtu, len);
 613
 614	rfcomm_make_uih(skb, d->addr);
 615	skb_queue_tail(&d->tx_queue, skb);
 616
 617	if (d->state == BT_CONNECTED &&
 618	    !test_bit(RFCOMM_TX_THROTTLED, &d->flags))
 619		rfcomm_schedule();
 620}
 621
 622void __rfcomm_dlc_throttle(struct rfcomm_dlc *d)
 623{
 624	BT_DBG("dlc %p state %ld", d, d->state);
 625
 626	if (!d->cfc) {
 627		d->v24_sig |= RFCOMM_V24_FC;
 628		set_bit(RFCOMM_MSC_PENDING, &d->flags);
 629	}
 630	rfcomm_schedule();
 631}
 632
 633void __rfcomm_dlc_unthrottle(struct rfcomm_dlc *d)
 634{
 635	BT_DBG("dlc %p state %ld", d, d->state);
 636
 637	if (!d->cfc) {
 638		d->v24_sig &= ~RFCOMM_V24_FC;
 639		set_bit(RFCOMM_MSC_PENDING, &d->flags);
 640	}
 641	rfcomm_schedule();
 642}
 643
 644/*
 645   Set/get modem status functions use _local_ status i.e. what we report
 646   to the other side.
 647   Remote status is provided by dlc->modem_status() callback.
 648 */
 649int rfcomm_dlc_set_modem_status(struct rfcomm_dlc *d, u8 v24_sig)
 650{
 651	BT_DBG("dlc %p state %ld v24_sig 0x%x",
 652			d, d->state, v24_sig);
 653
 654	if (test_bit(RFCOMM_RX_THROTTLED, &d->flags))
 655		v24_sig |= RFCOMM_V24_FC;
 656	else
 657		v24_sig &= ~RFCOMM_V24_FC;
 658
 659	d->v24_sig = v24_sig;
 660
 661	if (!test_and_set_bit(RFCOMM_MSC_PENDING, &d->flags))
 662		rfcomm_schedule();
 663
 664	return 0;
 665}
 666
 667int rfcomm_dlc_get_modem_status(struct rfcomm_dlc *d, u8 *v24_sig)
 668{
 669	BT_DBG("dlc %p state %ld v24_sig 0x%x",
 670			d, d->state, d->v24_sig);
 671
 672	*v24_sig = d->v24_sig;
 673	return 0;
 674}
 675
 676/* ---- RFCOMM sessions ---- */
 677static struct rfcomm_session *rfcomm_session_add(struct socket *sock, int state)
 678{
 679	struct rfcomm_session *s = kzalloc(sizeof(*s), GFP_KERNEL);
 680
 681	if (!s)
 682		return NULL;
 683
 684	BT_DBG("session %p sock %p", s, sock);
 685
 686	timer_setup(&s->timer, rfcomm_session_timeout, 0);
 687
 688	INIT_LIST_HEAD(&s->dlcs);
 689	s->state = state;
 690	s->sock  = sock;
 691
 692	s->mtu = RFCOMM_DEFAULT_MTU;
 693	s->cfc = disable_cfc ? RFCOMM_CFC_DISABLED : RFCOMM_CFC_UNKNOWN;
 694
 695	/* Do not increment module usage count for listening sessions.
 696	 * Otherwise we won't be able to unload the module. */
 697	if (state != BT_LISTEN)
 698		if (!try_module_get(THIS_MODULE)) {
 699			kfree(s);
 700			return NULL;
 701		}
 702
 703	list_add(&s->list, &session_list);
 704
 705	return s;
 706}
 707
 708static struct rfcomm_session *rfcomm_session_del(struct rfcomm_session *s)
 709{
 710	int state = s->state;
 711
 712	BT_DBG("session %p state %ld", s, s->state);
 713
 714	list_del(&s->list);
 715
 716	rfcomm_session_clear_timer(s);
 717	sock_release(s->sock);
 718	kfree(s);
 719
 720	if (state != BT_LISTEN)
 721		module_put(THIS_MODULE);
 722
 723	return NULL;
 724}
 725
 726static struct rfcomm_session *rfcomm_session_get(bdaddr_t *src, bdaddr_t *dst)
 727{
 728	struct rfcomm_session *s, *n;
 729	struct l2cap_chan *chan;
 730	list_for_each_entry_safe(s, n, &session_list, list) {
 731		chan = l2cap_pi(s->sock->sk)->chan;
 732
 733		if ((!bacmp(src, BDADDR_ANY) || !bacmp(&chan->src, src)) &&
 734		    !bacmp(&chan->dst, dst))
 735			return s;
 736	}
 737	return NULL;
 738}
 739
 740static struct rfcomm_session *rfcomm_session_close(struct rfcomm_session *s,
 741						   int err)
 742{
 743	struct rfcomm_dlc *d, *n;
 744
 745	s->state = BT_CLOSED;
 746
 747	BT_DBG("session %p state %ld err %d", s, s->state, err);
 748
 749	/* Close all dlcs */
 750	list_for_each_entry_safe(d, n, &s->dlcs, list) {
 751		d->state = BT_CLOSED;
 752		__rfcomm_dlc_close(d, err);
 753	}
 754
 755	rfcomm_session_clear_timer(s);
 756	return rfcomm_session_del(s);
 757}
 758
 759static struct rfcomm_session *rfcomm_session_create(bdaddr_t *src,
 760							bdaddr_t *dst,
 761							u8 sec_level,
 762							int *err)
 763{
 764	struct rfcomm_session *s = NULL;
 765	struct sockaddr_l2 addr;
 766	struct socket *sock;
 767	struct sock *sk;
 768
 769	BT_DBG("%pMR -> %pMR", src, dst);
 770
 771	*err = rfcomm_l2sock_create(&sock);
 772	if (*err < 0)
 773		return NULL;
 774
 775	bacpy(&addr.l2_bdaddr, src);
 776	addr.l2_family = AF_BLUETOOTH;
 777	addr.l2_psm    = 0;
 778	addr.l2_cid    = 0;
 779	addr.l2_bdaddr_type = BDADDR_BREDR;
 780	*err = kernel_bind(sock, (struct sockaddr *) &addr, sizeof(addr));
 781	if (*err < 0)
 782		goto failed;
 783
 784	/* Set L2CAP options */
 785	sk = sock->sk;
 786	lock_sock(sk);
 787	/* Set MTU to 0 so L2CAP can auto select the MTU */
 788	l2cap_pi(sk)->chan->imtu = 0;
 789	l2cap_pi(sk)->chan->sec_level = sec_level;
 790	if (l2cap_ertm)
 791		l2cap_pi(sk)->chan->mode = L2CAP_MODE_ERTM;
 792	release_sock(sk);
 793
 794	s = rfcomm_session_add(sock, BT_BOUND);
 795	if (!s) {
 796		*err = -ENOMEM;
 797		goto failed;
 798	}
 799
 800	s->initiator = 1;
 801
 802	bacpy(&addr.l2_bdaddr, dst);
 803	addr.l2_family = AF_BLUETOOTH;
 804	addr.l2_psm    = cpu_to_le16(L2CAP_PSM_RFCOMM);
 805	addr.l2_cid    = 0;
 806	addr.l2_bdaddr_type = BDADDR_BREDR;
 807	*err = kernel_connect(sock, (struct sockaddr *) &addr, sizeof(addr), O_NONBLOCK);
 808	if (*err == 0 || *err == -EINPROGRESS)
 809		return s;
 810
 811	return rfcomm_session_del(s);
 812
 813failed:
 814	sock_release(sock);
 815	return NULL;
 816}
 817
 818void rfcomm_session_getaddr(struct rfcomm_session *s, bdaddr_t *src, bdaddr_t *dst)
 819{
 820	struct l2cap_chan *chan = l2cap_pi(s->sock->sk)->chan;
 821	if (src)
 822		bacpy(src, &chan->src);
 823	if (dst)
 824		bacpy(dst, &chan->dst);
 825}
 826
 827/* ---- RFCOMM frame sending ---- */
 828static int rfcomm_send_frame(struct rfcomm_session *s, u8 *data, int len)
 829{
 830	struct kvec iv = { data, len };
 831	struct msghdr msg;
 832
 833	BT_DBG("session %p len %d", s, len);
 834
 835	memset(&msg, 0, sizeof(msg));
 836
 837	return kernel_sendmsg(s->sock, &msg, &iv, 1, len);
 838}
 839
 840static int rfcomm_send_cmd(struct rfcomm_session *s, struct rfcomm_cmd *cmd)
 841{
 842	BT_DBG("%p cmd %u", s, cmd->ctrl);
 843
 844	return rfcomm_send_frame(s, (void *) cmd, sizeof(*cmd));
 845}
 846
 847static int rfcomm_send_sabm(struct rfcomm_session *s, u8 dlci)
 848{
 849	struct rfcomm_cmd cmd;
 850
 851	BT_DBG("%p dlci %d", s, dlci);
 852
 853	cmd.addr = __addr(s->initiator, dlci);
 854	cmd.ctrl = __ctrl(RFCOMM_SABM, 1);
 855	cmd.len  = __len8(0);
 856	cmd.fcs  = __fcs2((u8 *) &cmd);
 857
 858	return rfcomm_send_cmd(s, &cmd);
 859}
 860
 861static int rfcomm_send_ua(struct rfcomm_session *s, u8 dlci)
 862{
 863	struct rfcomm_cmd cmd;
 864
 865	BT_DBG("%p dlci %d", s, dlci);
 866
 867	cmd.addr = __addr(!s->initiator, dlci);
 868	cmd.ctrl = __ctrl(RFCOMM_UA, 1);
 869	cmd.len  = __len8(0);
 870	cmd.fcs  = __fcs2((u8 *) &cmd);
 871
 872	return rfcomm_send_cmd(s, &cmd);
 873}
 874
 875static int rfcomm_send_disc(struct rfcomm_session *s, u8 dlci)
 876{
 877	struct rfcomm_cmd cmd;
 878
 879	BT_DBG("%p dlci %d", s, dlci);
 880
 881	cmd.addr = __addr(s->initiator, dlci);
 882	cmd.ctrl = __ctrl(RFCOMM_DISC, 1);
 883	cmd.len  = __len8(0);
 884	cmd.fcs  = __fcs2((u8 *) &cmd);
 885
 886	return rfcomm_send_cmd(s, &cmd);
 887}
 888
 889static int rfcomm_queue_disc(struct rfcomm_dlc *d)
 890{
 891	struct rfcomm_cmd *cmd;
 892	struct sk_buff *skb;
 893
 894	BT_DBG("dlc %p dlci %d", d, d->dlci);
 895
 896	skb = alloc_skb(sizeof(*cmd), GFP_KERNEL);
 897	if (!skb)
 898		return -ENOMEM;
 899
 900	cmd = __skb_put(skb, sizeof(*cmd));
 901	cmd->addr = d->addr;
 902	cmd->ctrl = __ctrl(RFCOMM_DISC, 1);
 903	cmd->len  = __len8(0);
 904	cmd->fcs  = __fcs2((u8 *) cmd);
 905
 906	skb_queue_tail(&d->tx_queue, skb);
 907	rfcomm_schedule();
 908	return 0;
 909}
 910
 911static int rfcomm_send_dm(struct rfcomm_session *s, u8 dlci)
 912{
 913	struct rfcomm_cmd cmd;
 914
 915	BT_DBG("%p dlci %d", s, dlci);
 916
 917	cmd.addr = __addr(!s->initiator, dlci);
 918	cmd.ctrl = __ctrl(RFCOMM_DM, 1);
 919	cmd.len  = __len8(0);
 920	cmd.fcs  = __fcs2((u8 *) &cmd);
 921
 922	return rfcomm_send_cmd(s, &cmd);
 923}
 924
 925static int rfcomm_send_nsc(struct rfcomm_session *s, int cr, u8 type)
 926{
 927	struct rfcomm_hdr *hdr;
 928	struct rfcomm_mcc *mcc;
 929	u8 buf[16], *ptr = buf;
 930
 931	BT_DBG("%p cr %d type %d", s, cr, type);
 932
 933	hdr = (void *) ptr; ptr += sizeof(*hdr);
 934	hdr->addr = __addr(s->initiator, 0);
 935	hdr->ctrl = __ctrl(RFCOMM_UIH, 0);
 936	hdr->len  = __len8(sizeof(*mcc) + 1);
 937
 938	mcc = (void *) ptr; ptr += sizeof(*mcc);
 939	mcc->type = __mcc_type(0, RFCOMM_NSC);
 940	mcc->len  = __len8(1);
 941
 942	/* Type that we didn't like */
 943	*ptr = __mcc_type(cr, type); ptr++;
 944
 945	*ptr = __fcs(buf); ptr++;
 946
 947	return rfcomm_send_frame(s, buf, ptr - buf);
 948}
 949
 950static int rfcomm_send_pn(struct rfcomm_session *s, int cr, struct rfcomm_dlc *d)
 951{
 952	struct rfcomm_hdr *hdr;
 953	struct rfcomm_mcc *mcc;
 954	struct rfcomm_pn  *pn;
 955	u8 buf[16], *ptr = buf;
 956
 957	BT_DBG("%p cr %d dlci %d mtu %d", s, cr, d->dlci, d->mtu);
 958
 959	hdr = (void *) ptr; ptr += sizeof(*hdr);
 960	hdr->addr = __addr(s->initiator, 0);
 961	hdr->ctrl = __ctrl(RFCOMM_UIH, 0);
 962	hdr->len  = __len8(sizeof(*mcc) + sizeof(*pn));
 963
 964	mcc = (void *) ptr; ptr += sizeof(*mcc);
 965	mcc->type = __mcc_type(cr, RFCOMM_PN);
 966	mcc->len  = __len8(sizeof(*pn));
 967
 968	pn = (void *) ptr; ptr += sizeof(*pn);
 969	pn->dlci        = d->dlci;
 970	pn->priority    = d->priority;
 971	pn->ack_timer   = 0;
 972	pn->max_retrans = 0;
 973
 974	if (s->cfc) {
 975		pn->flow_ctrl = cr ? 0xf0 : 0xe0;
 976		pn->credits = RFCOMM_DEFAULT_CREDITS;
 977	} else {
 978		pn->flow_ctrl = 0;
 979		pn->credits   = 0;
 980	}
 981
 982	if (cr && channel_mtu >= 0)
 983		pn->mtu = cpu_to_le16(channel_mtu);
 984	else
 985		pn->mtu = cpu_to_le16(d->mtu);
 986
 987	*ptr = __fcs(buf); ptr++;
 988
 989	return rfcomm_send_frame(s, buf, ptr - buf);
 990}
 991
 992int rfcomm_send_rpn(struct rfcomm_session *s, int cr, u8 dlci,
 993			u8 bit_rate, u8 data_bits, u8 stop_bits,
 994			u8 parity, u8 flow_ctrl_settings,
 995			u8 xon_char, u8 xoff_char, u16 param_mask)
 996{
 997	struct rfcomm_hdr *hdr;
 998	struct rfcomm_mcc *mcc;
 999	struct rfcomm_rpn *rpn;
1000	u8 buf[16], *ptr = buf;
1001
1002	BT_DBG("%p cr %d dlci %d bit_r 0x%x data_b 0x%x stop_b 0x%x parity 0x%x"
1003			" flwc_s 0x%x xon_c 0x%x xoff_c 0x%x p_mask 0x%x",
1004		s, cr, dlci, bit_rate, data_bits, stop_bits, parity,
1005		flow_ctrl_settings, xon_char, xoff_char, param_mask);
1006
1007	hdr = (void *) ptr; ptr += sizeof(*hdr);
1008	hdr->addr = __addr(s->initiator, 0);
1009	hdr->ctrl = __ctrl(RFCOMM_UIH, 0);
1010	hdr->len  = __len8(sizeof(*mcc) + sizeof(*rpn));
1011
1012	mcc = (void *) ptr; ptr += sizeof(*mcc);
1013	mcc->type = __mcc_type(cr, RFCOMM_RPN);
1014	mcc->len  = __len8(sizeof(*rpn));
1015
1016	rpn = (void *) ptr; ptr += sizeof(*rpn);
1017	rpn->dlci          = __addr(1, dlci);
1018	rpn->bit_rate      = bit_rate;
1019	rpn->line_settings = __rpn_line_settings(data_bits, stop_bits, parity);
1020	rpn->flow_ctrl     = flow_ctrl_settings;
1021	rpn->xon_char      = xon_char;
1022	rpn->xoff_char     = xoff_char;
1023	rpn->param_mask    = cpu_to_le16(param_mask);
1024
1025	*ptr = __fcs(buf); ptr++;
1026
1027	return rfcomm_send_frame(s, buf, ptr - buf);
1028}
1029
1030static int rfcomm_send_rls(struct rfcomm_session *s, int cr, u8 dlci, u8 status)
1031{
1032	struct rfcomm_hdr *hdr;
1033	struct rfcomm_mcc *mcc;
1034	struct rfcomm_rls *rls;
1035	u8 buf[16], *ptr = buf;
1036
1037	BT_DBG("%p cr %d status 0x%x", s, cr, status);
1038
1039	hdr = (void *) ptr; ptr += sizeof(*hdr);
1040	hdr->addr = __addr(s->initiator, 0);
1041	hdr->ctrl = __ctrl(RFCOMM_UIH, 0);
1042	hdr->len  = __len8(sizeof(*mcc) + sizeof(*rls));
1043
1044	mcc = (void *) ptr; ptr += sizeof(*mcc);
1045	mcc->type = __mcc_type(cr, RFCOMM_RLS);
1046	mcc->len  = __len8(sizeof(*rls));
1047
1048	rls = (void *) ptr; ptr += sizeof(*rls);
1049	rls->dlci   = __addr(1, dlci);
1050	rls->status = status;
1051
1052	*ptr = __fcs(buf); ptr++;
1053
1054	return rfcomm_send_frame(s, buf, ptr - buf);
1055}
1056
1057static int rfcomm_send_msc(struct rfcomm_session *s, int cr, u8 dlci, u8 v24_sig)
1058{
1059	struct rfcomm_hdr *hdr;
1060	struct rfcomm_mcc *mcc;
1061	struct rfcomm_msc *msc;
1062	u8 buf[16], *ptr = buf;
1063
1064	BT_DBG("%p cr %d v24 0x%x", s, cr, v24_sig);
1065
1066	hdr = (void *) ptr; ptr += sizeof(*hdr);
1067	hdr->addr = __addr(s->initiator, 0);
1068	hdr->ctrl = __ctrl(RFCOMM_UIH, 0);
1069	hdr->len  = __len8(sizeof(*mcc) + sizeof(*msc));
1070
1071	mcc = (void *) ptr; ptr += sizeof(*mcc);
1072	mcc->type = __mcc_type(cr, RFCOMM_MSC);
1073	mcc->len  = __len8(sizeof(*msc));
1074
1075	msc = (void *) ptr; ptr += sizeof(*msc);
1076	msc->dlci    = __addr(1, dlci);
1077	msc->v24_sig = v24_sig | 0x01;
1078
1079	*ptr = __fcs(buf); ptr++;
1080
1081	return rfcomm_send_frame(s, buf, ptr - buf);
1082}
1083
1084static int rfcomm_send_fcoff(struct rfcomm_session *s, int cr)
1085{
1086	struct rfcomm_hdr *hdr;
1087	struct rfcomm_mcc *mcc;
1088	u8 buf[16], *ptr = buf;
1089
1090	BT_DBG("%p cr %d", s, cr);
1091
1092	hdr = (void *) ptr; ptr += sizeof(*hdr);
1093	hdr->addr = __addr(s->initiator, 0);
1094	hdr->ctrl = __ctrl(RFCOMM_UIH, 0);
1095	hdr->len  = __len8(sizeof(*mcc));
1096
1097	mcc = (void *) ptr; ptr += sizeof(*mcc);
1098	mcc->type = __mcc_type(cr, RFCOMM_FCOFF);
1099	mcc->len  = __len8(0);
1100
1101	*ptr = __fcs(buf); ptr++;
1102
1103	return rfcomm_send_frame(s, buf, ptr - buf);
1104}
1105
1106static int rfcomm_send_fcon(struct rfcomm_session *s, int cr)
1107{
1108	struct rfcomm_hdr *hdr;
1109	struct rfcomm_mcc *mcc;
1110	u8 buf[16], *ptr = buf;
1111
1112	BT_DBG("%p cr %d", s, cr);
1113
1114	hdr = (void *) ptr; ptr += sizeof(*hdr);
1115	hdr->addr = __addr(s->initiator, 0);
1116	hdr->ctrl = __ctrl(RFCOMM_UIH, 0);
1117	hdr->len  = __len8(sizeof(*mcc));
1118
1119	mcc = (void *) ptr; ptr += sizeof(*mcc);
1120	mcc->type = __mcc_type(cr, RFCOMM_FCON);
1121	mcc->len  = __len8(0);
1122
1123	*ptr = __fcs(buf); ptr++;
1124
1125	return rfcomm_send_frame(s, buf, ptr - buf);
1126}
1127
1128static int rfcomm_send_test(struct rfcomm_session *s, int cr, u8 *pattern, int len)
1129{
1130	struct socket *sock = s->sock;
1131	struct kvec iv[3];
1132	struct msghdr msg;
1133	unsigned char hdr[5], crc[1];
1134
1135	if (len > 125)
1136		return -EINVAL;
1137
1138	BT_DBG("%p cr %d", s, cr);
1139
1140	hdr[0] = __addr(s->initiator, 0);
1141	hdr[1] = __ctrl(RFCOMM_UIH, 0);
1142	hdr[2] = 0x01 | ((len + 2) << 1);
1143	hdr[3] = 0x01 | ((cr & 0x01) << 1) | (RFCOMM_TEST << 2);
1144	hdr[4] = 0x01 | (len << 1);
1145
1146	crc[0] = __fcs(hdr);
1147
1148	iv[0].iov_base = hdr;
1149	iv[0].iov_len  = 5;
1150	iv[1].iov_base = pattern;
1151	iv[1].iov_len  = len;
1152	iv[2].iov_base = crc;
1153	iv[2].iov_len  = 1;
1154
1155	memset(&msg, 0, sizeof(msg));
1156
1157	return kernel_sendmsg(sock, &msg, iv, 3, 6 + len);
1158}
1159
1160static int rfcomm_send_credits(struct rfcomm_session *s, u8 addr, u8 credits)
1161{
1162	struct rfcomm_hdr *hdr;
1163	u8 buf[16], *ptr = buf;
1164
1165	BT_DBG("%p addr %d credits %d", s, addr, credits);
1166
1167	hdr = (void *) ptr; ptr += sizeof(*hdr);
1168	hdr->addr = addr;
1169	hdr->ctrl = __ctrl(RFCOMM_UIH, 1);
1170	hdr->len  = __len8(0);
1171
1172	*ptr = credits; ptr++;
1173
1174	*ptr = __fcs(buf); ptr++;
1175
1176	return rfcomm_send_frame(s, buf, ptr - buf);
1177}
1178
1179static void rfcomm_make_uih(struct sk_buff *skb, u8 addr)
1180{
1181	struct rfcomm_hdr *hdr;
1182	int len = skb->len;
1183	u8 *crc;
1184
1185	if (len > 127) {
1186		hdr = skb_push(skb, 4);
1187		put_unaligned(cpu_to_le16(__len16(len)), (__le16 *) &hdr->len);
1188	} else {
1189		hdr = skb_push(skb, 3);
1190		hdr->len = __len8(len);
1191	}
1192	hdr->addr = addr;
1193	hdr->ctrl = __ctrl(RFCOMM_UIH, 0);
1194
1195	crc = skb_put(skb, 1);
1196	*crc = __fcs((void *) hdr);
1197}
1198
1199/* ---- RFCOMM frame reception ---- */
1200static struct rfcomm_session *rfcomm_recv_ua(struct rfcomm_session *s, u8 dlci)
1201{
1202	BT_DBG("session %p state %ld dlci %d", s, s->state, dlci);
1203
1204	if (dlci) {
1205		/* Data channel */
1206		struct rfcomm_dlc *d = rfcomm_dlc_get(s, dlci);
1207		if (!d) {
1208			rfcomm_send_dm(s, dlci);
1209			return s;
1210		}
1211
1212		switch (d->state) {
1213		case BT_CONNECT:
1214			rfcomm_dlc_clear_timer(d);
1215
1216			rfcomm_dlc_lock(d);
1217			d->state = BT_CONNECTED;
1218			d->state_change(d, 0);
1219			rfcomm_dlc_unlock(d);
1220
1221			rfcomm_send_msc(s, 1, dlci, d->v24_sig);
1222			break;
1223
1224		case BT_DISCONN:
1225			d->state = BT_CLOSED;
1226			__rfcomm_dlc_close(d, 0);
1227
1228			if (list_empty(&s->dlcs)) {
1229				s->state = BT_DISCONN;
1230				rfcomm_send_disc(s, 0);
1231				rfcomm_session_clear_timer(s);
1232			}
1233
1234			break;
1235		}
1236	} else {
1237		/* Control channel */
1238		switch (s->state) {
1239		case BT_CONNECT:
1240			s->state = BT_CONNECTED;
1241			rfcomm_process_connect(s);
1242			break;
1243
1244		case BT_DISCONN:
1245			s = rfcomm_session_close(s, ECONNRESET);
1246			break;
1247		}
1248	}
1249	return s;
1250}
1251
1252static struct rfcomm_session *rfcomm_recv_dm(struct rfcomm_session *s, u8 dlci)
1253{
1254	int err = 0;
1255
1256	BT_DBG("session %p state %ld dlci %d", s, s->state, dlci);
1257
1258	if (dlci) {
1259		/* Data DLC */
1260		struct rfcomm_dlc *d = rfcomm_dlc_get(s, dlci);
1261		if (d) {
1262			if (d->state == BT_CONNECT || d->state == BT_CONFIG)
1263				err = ECONNREFUSED;
1264			else
1265				err = ECONNRESET;
1266
1267			d->state = BT_CLOSED;
1268			__rfcomm_dlc_close(d, err);
1269		}
1270	} else {
1271		if (s->state == BT_CONNECT)
1272			err = ECONNREFUSED;
1273		else
1274			err = ECONNRESET;
1275
1276		s = rfcomm_session_close(s, err);
1277	}
1278	return s;
1279}
1280
1281static struct rfcomm_session *rfcomm_recv_disc(struct rfcomm_session *s,
1282					       u8 dlci)
1283{
1284	int err = 0;
1285
1286	BT_DBG("session %p state %ld dlci %d", s, s->state, dlci);
1287
1288	if (dlci) {
1289		struct rfcomm_dlc *d = rfcomm_dlc_get(s, dlci);
1290		if (d) {
1291			rfcomm_send_ua(s, dlci);
1292
1293			if (d->state == BT_CONNECT || d->state == BT_CONFIG)
1294				err = ECONNREFUSED;
1295			else
1296				err = ECONNRESET;
1297
1298			d->state = BT_CLOSED;
1299			__rfcomm_dlc_close(d, err);
1300		} else
1301			rfcomm_send_dm(s, dlci);
1302
1303	} else {
1304		rfcomm_send_ua(s, 0);
1305
1306		if (s->state == BT_CONNECT)
1307			err = ECONNREFUSED;
1308		else
1309			err = ECONNRESET;
1310
1311		s = rfcomm_session_close(s, err);
1312	}
1313	return s;
1314}
1315
1316void rfcomm_dlc_accept(struct rfcomm_dlc *d)
1317{
1318	struct sock *sk = d->session->sock->sk;
1319	struct l2cap_conn *conn = l2cap_pi(sk)->chan->conn;
1320
1321	BT_DBG("dlc %p", d);
1322
1323	rfcomm_send_ua(d->session, d->dlci);
1324
1325	rfcomm_dlc_clear_timer(d);
1326
1327	rfcomm_dlc_lock(d);
1328	d->state = BT_CONNECTED;
1329	d->state_change(d, 0);
1330	rfcomm_dlc_unlock(d);
1331
1332	if (d->role_switch)
1333		hci_conn_switch_role(conn->hcon, 0x00);
1334
1335	rfcomm_send_msc(d->session, 1, d->dlci, d->v24_sig);
1336}
1337
1338static void rfcomm_check_accept(struct rfcomm_dlc *d)
1339{
1340	if (rfcomm_check_security(d)) {
1341		if (d->defer_setup) {
1342			set_bit(RFCOMM_DEFER_SETUP, &d->flags);
1343			rfcomm_dlc_set_timer(d, RFCOMM_AUTH_TIMEOUT);
1344
1345			rfcomm_dlc_lock(d);
1346			d->state = BT_CONNECT2;
1347			d->state_change(d, 0);
1348			rfcomm_dlc_unlock(d);
1349		} else
1350			rfcomm_dlc_accept(d);
1351	} else {
1352		set_bit(RFCOMM_AUTH_PENDING, &d->flags);
1353		rfcomm_dlc_set_timer(d, RFCOMM_AUTH_TIMEOUT);
1354	}
1355}
1356
1357static int rfcomm_recv_sabm(struct rfcomm_session *s, u8 dlci)
1358{
1359	struct rfcomm_dlc *d;
1360	u8 channel;
1361
1362	BT_DBG("session %p state %ld dlci %d", s, s->state, dlci);
1363
1364	if (!dlci) {
1365		rfcomm_send_ua(s, 0);
1366
1367		if (s->state == BT_OPEN) {
1368			s->state = BT_CONNECTED;
1369			rfcomm_process_connect(s);
1370		}
1371		return 0;
1372	}
1373
1374	/* Check if DLC exists */
1375	d = rfcomm_dlc_get(s, dlci);
1376	if (d) {
1377		if (d->state == BT_OPEN) {
1378			/* DLC was previously opened by PN request */
1379			rfcomm_check_accept(d);
1380		}
1381		return 0;
1382	}
1383
1384	/* Notify socket layer about incoming connection */
1385	channel = __srv_channel(dlci);
1386	if (rfcomm_connect_ind(s, channel, &d)) {
1387		d->dlci = dlci;
1388		d->addr = __addr(s->initiator, dlci);
1389		rfcomm_dlc_link(s, d);
1390
1391		rfcomm_check_accept(d);
1392	} else {
1393		rfcomm_send_dm(s, dlci);
1394	}
1395
1396	return 0;
1397}
1398
1399static int rfcomm_apply_pn(struct rfcomm_dlc *d, int cr, struct rfcomm_pn *pn)
1400{
1401	struct rfcomm_session *s = d->session;
1402
1403	BT_DBG("dlc %p state %ld dlci %d mtu %d fc 0x%x credits %d",
1404			d, d->state, d->dlci, pn->mtu, pn->flow_ctrl, pn->credits);
1405
1406	if ((pn->flow_ctrl == 0xf0 && s->cfc != RFCOMM_CFC_DISABLED) ||
1407						pn->flow_ctrl == 0xe0) {
1408		d->cfc = RFCOMM_CFC_ENABLED;
1409		d->tx_credits = pn->credits;
1410	} else {
1411		d->cfc = RFCOMM_CFC_DISABLED;
1412		set_bit(RFCOMM_TX_THROTTLED, &d->flags);
1413	}
1414
1415	if (s->cfc == RFCOMM_CFC_UNKNOWN)
1416		s->cfc = d->cfc;
1417
1418	d->priority = pn->priority;
1419
1420	d->mtu = __le16_to_cpu(pn->mtu);
1421
1422	if (cr && d->mtu > s->mtu)
1423		d->mtu = s->mtu;
1424
1425	return 0;
1426}
1427
1428static int rfcomm_recv_pn(struct rfcomm_session *s, int cr, struct sk_buff *skb)
1429{
1430	struct rfcomm_pn *pn = (void *) skb->data;
1431	struct rfcomm_dlc *d;
1432	u8 dlci = pn->dlci;
1433
1434	BT_DBG("session %p state %ld dlci %d", s, s->state, dlci);
1435
1436	if (!dlci)
1437		return 0;
1438
1439	d = rfcomm_dlc_get(s, dlci);
1440	if (d) {
1441		if (cr) {
1442			/* PN request */
1443			rfcomm_apply_pn(d, cr, pn);
1444			rfcomm_send_pn(s, 0, d);
1445		} else {
1446			/* PN response */
1447			switch (d->state) {
1448			case BT_CONFIG:
1449				rfcomm_apply_pn(d, cr, pn);
1450
1451				d->state = BT_CONNECT;
1452				rfcomm_send_sabm(s, d->dlci);
1453				break;
1454			}
1455		}
1456	} else {
1457		u8 channel = __srv_channel(dlci);
1458
1459		if (!cr)
1460			return 0;
1461
1462		/* PN request for non existing DLC.
1463		 * Assume incoming connection. */
1464		if (rfcomm_connect_ind(s, channel, &d)) {
1465			d->dlci = dlci;
1466			d->addr = __addr(s->initiator, dlci);
1467			rfcomm_dlc_link(s, d);
1468
1469			rfcomm_apply_pn(d, cr, pn);
1470
1471			d->state = BT_OPEN;
1472			rfcomm_send_pn(s, 0, d);
1473		} else {
1474			rfcomm_send_dm(s, dlci);
1475		}
1476	}
1477	return 0;
1478}
1479
1480static int rfcomm_recv_rpn(struct rfcomm_session *s, int cr, int len, struct sk_buff *skb)
1481{
1482	struct rfcomm_rpn *rpn = (void *) skb->data;
1483	u8 dlci = __get_dlci(rpn->dlci);
1484
1485	u8 bit_rate  = 0;
1486	u8 data_bits = 0;
1487	u8 stop_bits = 0;
1488	u8 parity    = 0;
1489	u8 flow_ctrl = 0;
1490	u8 xon_char  = 0;
1491	u8 xoff_char = 0;
1492	u16 rpn_mask = RFCOMM_RPN_PM_ALL;
1493
1494	BT_DBG("dlci %d cr %d len 0x%x bitr 0x%x line 0x%x flow 0x%x xonc 0x%x xoffc 0x%x pm 0x%x",
1495		dlci, cr, len, rpn->bit_rate, rpn->line_settings, rpn->flow_ctrl,
1496		rpn->xon_char, rpn->xoff_char, rpn->param_mask);
1497
1498	if (!cr)
1499		return 0;
1500
1501	if (len == 1) {
1502		/* This is a request, return default (according to ETSI TS 07.10) settings */
1503		bit_rate  = RFCOMM_RPN_BR_9600;
1504		data_bits = RFCOMM_RPN_DATA_8;
1505		stop_bits = RFCOMM_RPN_STOP_1;
1506		parity    = RFCOMM_RPN_PARITY_NONE;
1507		flow_ctrl = RFCOMM_RPN_FLOW_NONE;
1508		xon_char  = RFCOMM_RPN_XON_CHAR;
1509		xoff_char = RFCOMM_RPN_XOFF_CHAR;
1510		goto rpn_out;
1511	}
1512
1513	/* Check for sane values, ignore/accept bit_rate, 8 bits, 1 stop bit,
1514	 * no parity, no flow control lines, normal XON/XOFF chars */
1515
1516	if (rpn->param_mask & cpu_to_le16(RFCOMM_RPN_PM_BITRATE)) {
1517		bit_rate = rpn->bit_rate;
1518		if (bit_rate > RFCOMM_RPN_BR_230400) {
1519			BT_DBG("RPN bit rate mismatch 0x%x", bit_rate);
1520			bit_rate = RFCOMM_RPN_BR_9600;
1521			rpn_mask ^= RFCOMM_RPN_PM_BITRATE;
1522		}
1523	}
1524
1525	if (rpn->param_mask & cpu_to_le16(RFCOMM_RPN_PM_DATA)) {
1526		data_bits = __get_rpn_data_bits(rpn->line_settings);
1527		if (data_bits != RFCOMM_RPN_DATA_8) {
1528			BT_DBG("RPN data bits mismatch 0x%x", data_bits);
1529			data_bits = RFCOMM_RPN_DATA_8;
1530			rpn_mask ^= RFCOMM_RPN_PM_DATA;
1531		}
1532	}
1533
1534	if (rpn->param_mask & cpu_to_le16(RFCOMM_RPN_PM_STOP)) {
1535		stop_bits = __get_rpn_stop_bits(rpn->line_settings);
1536		if (stop_bits != RFCOMM_RPN_STOP_1) {
1537			BT_DBG("RPN stop bits mismatch 0x%x", stop_bits);
1538			stop_bits = RFCOMM_RPN_STOP_1;
1539			rpn_mask ^= RFCOMM_RPN_PM_STOP;
1540		}
1541	}
1542
1543	if (rpn->param_mask & cpu_to_le16(RFCOMM_RPN_PM_PARITY)) {
1544		parity = __get_rpn_parity(rpn->line_settings);
1545		if (parity != RFCOMM_RPN_PARITY_NONE) {
1546			BT_DBG("RPN parity mismatch 0x%x", parity);
1547			parity = RFCOMM_RPN_PARITY_NONE;
1548			rpn_mask ^= RFCOMM_RPN_PM_PARITY;
1549		}
1550	}
1551
1552	if (rpn->param_mask & cpu_to_le16(RFCOMM_RPN_PM_FLOW)) {
1553		flow_ctrl = rpn->flow_ctrl;
1554		if (flow_ctrl != RFCOMM_RPN_FLOW_NONE) {
1555			BT_DBG("RPN flow ctrl mismatch 0x%x", flow_ctrl);
1556			flow_ctrl = RFCOMM_RPN_FLOW_NONE;
1557			rpn_mask ^= RFCOMM_RPN_PM_FLOW;
1558		}
1559	}
1560
1561	if (rpn->param_mask & cpu_to_le16(RFCOMM_RPN_PM_XON)) {
1562		xon_char = rpn->xon_char;
1563		if (xon_char != RFCOMM_RPN_XON_CHAR) {
1564			BT_DBG("RPN XON char mismatch 0x%x", xon_char);
1565			xon_char = RFCOMM_RPN_XON_CHAR;
1566			rpn_mask ^= RFCOMM_RPN_PM_XON;
1567		}
1568	}
1569
1570	if (rpn->param_mask & cpu_to_le16(RFCOMM_RPN_PM_XOFF)) {
1571		xoff_char = rpn->xoff_char;
1572		if (xoff_char != RFCOMM_RPN_XOFF_CHAR) {
1573			BT_DBG("RPN XOFF char mismatch 0x%x", xoff_char);
1574			xoff_char = RFCOMM_RPN_XOFF_CHAR;
1575			rpn_mask ^= RFCOMM_RPN_PM_XOFF;
1576		}
1577	}
1578
1579rpn_out:
1580	rfcomm_send_rpn(s, 0, dlci, bit_rate, data_bits, stop_bits,
1581			parity, flow_ctrl, xon_char, xoff_char, rpn_mask);
1582
1583	return 0;
1584}
1585
1586static int rfcomm_recv_rls(struct rfcomm_session *s, int cr, struct sk_buff *skb)
1587{
1588	struct rfcomm_rls *rls = (void *) skb->data;
1589	u8 dlci = __get_dlci(rls->dlci);
1590
1591	BT_DBG("dlci %d cr %d status 0x%x", dlci, cr, rls->status);
1592
1593	if (!cr)
1594		return 0;
1595
1596	/* We should probably do something with this information here. But
1597	 * for now it's sufficient just to reply -- Bluetooth 1.1 says it's
1598	 * mandatory to recognise and respond to RLS */
1599
1600	rfcomm_send_rls(s, 0, dlci, rls->status);
1601
1602	return 0;
1603}
1604
1605static int rfcomm_recv_msc(struct rfcomm_session *s, int cr, struct sk_buff *skb)
1606{
1607	struct rfcomm_msc *msc = (void *) skb->data;
1608	struct rfcomm_dlc *d;
1609	u8 dlci = __get_dlci(msc->dlci);
1610
1611	BT_DBG("dlci %d cr %d v24 0x%x", dlci, cr, msc->v24_sig);
1612
1613	d = rfcomm_dlc_get(s, dlci);
1614	if (!d)
1615		return 0;
1616
1617	if (cr) {
1618		if (msc->v24_sig & RFCOMM_V24_FC && !d->cfc)
1619			set_bit(RFCOMM_TX_THROTTLED, &d->flags);
1620		else
1621			clear_bit(RFCOMM_TX_THROTTLED, &d->flags);
1622
1623		rfcomm_dlc_lock(d);
1624
1625		d->remote_v24_sig = msc->v24_sig;
1626
1627		if (d->modem_status)
1628			d->modem_status(d, msc->v24_sig);
1629
1630		rfcomm_dlc_unlock(d);
1631
1632		rfcomm_send_msc(s, 0, dlci, msc->v24_sig);
1633
1634		d->mscex |= RFCOMM_MSCEX_RX;
1635	} else
1636		d->mscex |= RFCOMM_MSCEX_TX;
1637
1638	return 0;
1639}
1640
1641static int rfcomm_recv_mcc(struct rfcomm_session *s, struct sk_buff *skb)
1642{
1643	struct rfcomm_mcc *mcc = (void *) skb->data;
1644	u8 type, cr, len;
1645
1646	cr   = __test_cr(mcc->type);
1647	type = __get_mcc_type(mcc->type);
1648	len  = __get_mcc_len(mcc->len);
1649
1650	BT_DBG("%p type 0x%x cr %d", s, type, cr);
1651
1652	skb_pull(skb, 2);
1653
1654	switch (type) {
1655	case RFCOMM_PN:
1656		rfcomm_recv_pn(s, cr, skb);
1657		break;
1658
1659	case RFCOMM_RPN:
1660		rfcomm_recv_rpn(s, cr, len, skb);
1661		break;
1662
1663	case RFCOMM_RLS:
1664		rfcomm_recv_rls(s, cr, skb);
1665		break;
1666
1667	case RFCOMM_MSC:
1668		rfcomm_recv_msc(s, cr, skb);
1669		break;
1670
1671	case RFCOMM_FCOFF:
1672		if (cr) {
1673			set_bit(RFCOMM_TX_THROTTLED, &s->flags);
1674			rfcomm_send_fcoff(s, 0);
1675		}
1676		break;
1677
1678	case RFCOMM_FCON:
1679		if (cr) {
1680			clear_bit(RFCOMM_TX_THROTTLED, &s->flags);
1681			rfcomm_send_fcon(s, 0);
1682		}
1683		break;
1684
1685	case RFCOMM_TEST:
1686		if (cr)
1687			rfcomm_send_test(s, 0, skb->data, skb->len);
1688		break;
1689
1690	case RFCOMM_NSC:
1691		break;
1692
1693	default:
1694		BT_ERR("Unknown control type 0x%02x", type);
1695		rfcomm_send_nsc(s, cr, type);
1696		break;
1697	}
1698	return 0;
1699}
1700
1701static int rfcomm_recv_data(struct rfcomm_session *s, u8 dlci, int pf, struct sk_buff *skb)
1702{
1703	struct rfcomm_dlc *d;
1704
1705	BT_DBG("session %p state %ld dlci %d pf %d", s, s->state, dlci, pf);
1706
1707	d = rfcomm_dlc_get(s, dlci);
1708	if (!d) {
1709		rfcomm_send_dm(s, dlci);
1710		goto drop;
1711	}
1712
1713	if (pf && d->cfc) {
1714		u8 credits = *(u8 *) skb->data; skb_pull(skb, 1);
1715
1716		d->tx_credits += credits;
1717		if (d->tx_credits)
1718			clear_bit(RFCOMM_TX_THROTTLED, &d->flags);
1719	}
1720
1721	if (skb->len && d->state == BT_CONNECTED) {
1722		rfcomm_dlc_lock(d);
1723		d->rx_credits--;
1724		d->data_ready(d, skb);
1725		rfcomm_dlc_unlock(d);
1726		return 0;
1727	}
1728
1729drop:
1730	kfree_skb(skb);
1731	return 0;
1732}
1733
1734static struct rfcomm_session *rfcomm_recv_frame(struct rfcomm_session *s,
1735						struct sk_buff *skb)
1736{
1737	struct rfcomm_hdr *hdr = (void *) skb->data;
1738	u8 type, dlci, fcs;
1739
1740	if (!s) {
1741		/* no session, so free socket data */
1742		kfree_skb(skb);
1743		return s;
1744	}
1745
1746	dlci = __get_dlci(hdr->addr);
1747	type = __get_type(hdr->ctrl);
1748
1749	/* Trim FCS */
1750	skb->len--; skb->tail--;
1751	fcs = *(u8 *)skb_tail_pointer(skb);
1752
1753	if (__check_fcs(skb->data, type, fcs)) {
1754		BT_ERR("bad checksum in packet");
1755		kfree_skb(skb);
1756		return s;
1757	}
1758
1759	if (__test_ea(hdr->len))
1760		skb_pull(skb, 3);
1761	else
1762		skb_pull(skb, 4);
1763
1764	switch (type) {
1765	case RFCOMM_SABM:
1766		if (__test_pf(hdr->ctrl))
1767			rfcomm_recv_sabm(s, dlci);
1768		break;
1769
1770	case RFCOMM_DISC:
1771		if (__test_pf(hdr->ctrl))
1772			s = rfcomm_recv_disc(s, dlci);
1773		break;
1774
1775	case RFCOMM_UA:
1776		if (__test_pf(hdr->ctrl))
1777			s = rfcomm_recv_ua(s, dlci);
1778		break;
1779
1780	case RFCOMM_DM:
1781		s = rfcomm_recv_dm(s, dlci);
1782		break;
1783
1784	case RFCOMM_UIH:
1785		if (dlci) {
1786			rfcomm_recv_data(s, dlci, __test_pf(hdr->ctrl), skb);
1787			return s;
1788		}
1789		rfcomm_recv_mcc(s, skb);
1790		break;
1791
1792	default:
1793		BT_ERR("Unknown packet type 0x%02x", type);
1794		break;
1795	}
1796	kfree_skb(skb);
1797	return s;
1798}
1799
1800/* ---- Connection and data processing ---- */
1801
1802static void rfcomm_process_connect(struct rfcomm_session *s)
1803{
1804	struct rfcomm_dlc *d, *n;
1805
1806	BT_DBG("session %p state %ld", s, s->state);
1807
1808	list_for_each_entry_safe(d, n, &s->dlcs, list) {
1809		if (d->state == BT_CONFIG) {
1810			d->mtu = s->mtu;
1811			if (rfcomm_check_security(d)) {
1812				rfcomm_send_pn(s, 1, d);
1813			} else {
1814				set_bit(RFCOMM_AUTH_PENDING, &d->flags);
1815				rfcomm_dlc_set_timer(d, RFCOMM_AUTH_TIMEOUT);
1816			}
1817		}
1818	}
1819}
1820
1821/* Send data queued for the DLC.
1822 * Return number of frames left in the queue.
1823 */
1824static int rfcomm_process_tx(struct rfcomm_dlc *d)
1825{
1826	struct sk_buff *skb;
1827	int err;
1828
1829	BT_DBG("dlc %p state %ld cfc %d rx_credits %d tx_credits %d",
1830			d, d->state, d->cfc, d->rx_credits, d->tx_credits);
1831
1832	/* Send pending MSC */
1833	if (test_and_clear_bit(RFCOMM_MSC_PENDING, &d->flags))
1834		rfcomm_send_msc(d->session, 1, d->dlci, d->v24_sig);
1835
1836	if (d->cfc) {
1837		/* CFC enabled.
1838		 * Give them some credits */
1839		if (!test_bit(RFCOMM_RX_THROTTLED, &d->flags) &&
1840				d->rx_credits <= (d->cfc >> 2)) {
1841			rfcomm_send_credits(d->session, d->addr, d->cfc - d->rx_credits);
1842			d->rx_credits = d->cfc;
1843		}
1844	} else {
1845		/* CFC disabled.
1846		 * Give ourselves some credits */
1847		d->tx_credits = 5;
1848	}
1849
1850	if (test_bit(RFCOMM_TX_THROTTLED, &d->flags))
1851		return skb_queue_len(&d->tx_queue);
1852
1853	while (d->tx_credits && (skb = skb_dequeue(&d->tx_queue))) {
1854		err = rfcomm_send_frame(d->session, skb->data, skb->len);
1855		if (err < 0) {
1856			skb_queue_head(&d->tx_queue, skb);
1857			break;
1858		}
1859		kfree_skb(skb);
1860		d->tx_credits--;
1861	}
1862
1863	if (d->cfc && !d->tx_credits) {
1864		/* We're out of TX credits.
1865		 * Set TX_THROTTLED flag to avoid unnesary wakeups by dlc_send. */
1866		set_bit(RFCOMM_TX_THROTTLED, &d->flags);
1867	}
1868
1869	return skb_queue_len(&d->tx_queue);
1870}
1871
1872static void rfcomm_process_dlcs(struct rfcomm_session *s)
1873{
1874	struct rfcomm_dlc *d, *n;
1875
1876	BT_DBG("session %p state %ld", s, s->state);
1877
1878	list_for_each_entry_safe(d, n, &s->dlcs, list) {
1879		if (test_bit(RFCOMM_TIMED_OUT, &d->flags)) {
1880			__rfcomm_dlc_close(d, ETIMEDOUT);
1881			continue;
1882		}
1883
1884		if (test_bit(RFCOMM_ENC_DROP, &d->flags)) {
1885			__rfcomm_dlc_close(d, ECONNREFUSED);
1886			continue;
1887		}
1888
1889		if (test_and_clear_bit(RFCOMM_AUTH_ACCEPT, &d->flags)) {
1890			rfcomm_dlc_clear_timer(d);
1891			if (d->out) {
1892				rfcomm_send_pn(s, 1, d);
1893				rfcomm_dlc_set_timer(d, RFCOMM_CONN_TIMEOUT);
1894			} else {
1895				if (d->defer_setup) {
1896					set_bit(RFCOMM_DEFER_SETUP, &d->flags);
1897					rfcomm_dlc_set_timer(d, RFCOMM_AUTH_TIMEOUT);
1898
1899					rfcomm_dlc_lock(d);
1900					d->state = BT_CONNECT2;
1901					d->state_change(d, 0);
1902					rfcomm_dlc_unlock(d);
1903				} else
1904					rfcomm_dlc_accept(d);
1905			}
1906			continue;
1907		} else if (test_and_clear_bit(RFCOMM_AUTH_REJECT, &d->flags)) {
1908			rfcomm_dlc_clear_timer(d);
1909			if (!d->out)
1910				rfcomm_send_dm(s, d->dlci);
1911			else
1912				d->state = BT_CLOSED;
1913			__rfcomm_dlc_close(d, ECONNREFUSED);
1914			continue;
1915		}
1916
1917		if (test_bit(RFCOMM_SEC_PENDING, &d->flags))
1918			continue;
1919
1920		if (test_bit(RFCOMM_TX_THROTTLED, &s->flags))
1921			continue;
1922
1923		if ((d->state == BT_CONNECTED || d->state == BT_DISCONN) &&
1924						d->mscex == RFCOMM_MSCEX_OK)
1925			rfcomm_process_tx(d);
1926	}
1927}
1928
1929static struct rfcomm_session *rfcomm_process_rx(struct rfcomm_session *s)
1930{
1931	struct socket *sock = s->sock;
1932	struct sock *sk = sock->sk;
1933	struct sk_buff *skb;
1934
1935	BT_DBG("session %p state %ld qlen %d", s, s->state, skb_queue_len(&sk->sk_receive_queue));
1936
1937	/* Get data directly from socket receive queue without copying it. */
1938	while ((skb = skb_dequeue(&sk->sk_receive_queue))) {
1939		skb_orphan(skb);
1940		if (!skb_linearize(skb)) {
1941			s = rfcomm_recv_frame(s, skb);
1942			if (!s)
1943				break;
1944		} else {
1945			kfree_skb(skb);
1946		}
1947	}
1948
1949	if (s && (sk->sk_state == BT_CLOSED))
1950		s = rfcomm_session_close(s, sk->sk_err);
1951
1952	return s;
1953}
1954
1955static void rfcomm_accept_connection(struct rfcomm_session *s)
1956{
1957	struct socket *sock = s->sock, *nsock;
1958	int err;
1959
1960	/* Fast check for a new connection.
1961	 * Avoids unnesesary socket allocations. */
1962	if (list_empty(&bt_sk(sock->sk)->accept_q))
1963		return;
1964
1965	BT_DBG("session %p", s);
1966
1967	err = kernel_accept(sock, &nsock, O_NONBLOCK);
1968	if (err < 0)
1969		return;
1970
1971	/* Set our callbacks */
1972	nsock->sk->sk_data_ready   = rfcomm_l2data_ready;
1973	nsock->sk->sk_state_change = rfcomm_l2state_change;
1974
1975	s = rfcomm_session_add(nsock, BT_OPEN);
1976	if (s) {
1977		/* We should adjust MTU on incoming sessions.
1978		 * L2CAP MTU minus UIH header and FCS. */
1979		s->mtu = min(l2cap_pi(nsock->sk)->chan->omtu,
1980				l2cap_pi(nsock->sk)->chan->imtu) - 5;
1981
1982		rfcomm_schedule();
1983	} else
1984		sock_release(nsock);
1985}
1986
1987static struct rfcomm_session *rfcomm_check_connection(struct rfcomm_session *s)
1988{
1989	struct sock *sk = s->sock->sk;
1990
1991	BT_DBG("%p state %ld", s, s->state);
1992
1993	switch (sk->sk_state) {
1994	case BT_CONNECTED:
1995		s->state = BT_CONNECT;
1996
1997		/* We can adjust MTU on outgoing sessions.
1998		 * L2CAP MTU minus UIH header and FCS. */
1999		s->mtu = min(l2cap_pi(sk)->chan->omtu, l2cap_pi(sk)->chan->imtu) - 5;
2000
2001		rfcomm_send_sabm(s, 0);
2002		break;
2003
2004	case BT_CLOSED:
2005		s = rfcomm_session_close(s, sk->sk_err);
2006		break;
2007	}
2008	return s;
2009}
2010
2011static void rfcomm_process_sessions(void)
2012{
2013	struct rfcomm_session *s, *n;
2014
2015	rfcomm_lock();
2016
2017	list_for_each_entry_safe(s, n, &session_list, list) {
2018		if (test_and_clear_bit(RFCOMM_TIMED_OUT, &s->flags)) {
2019			s->state = BT_DISCONN;
2020			rfcomm_send_disc(s, 0);
2021			continue;
2022		}
2023
2024		switch (s->state) {
2025		case BT_LISTEN:
2026			rfcomm_accept_connection(s);
2027			continue;
2028
2029		case BT_BOUND:
2030			s = rfcomm_check_connection(s);
2031			break;
2032
2033		default:
2034			s = rfcomm_process_rx(s);
2035			break;
2036		}
2037
2038		if (s)
2039			rfcomm_process_dlcs(s);
2040	}
2041
2042	rfcomm_unlock();
2043}
2044
2045static int rfcomm_add_listener(bdaddr_t *ba)
2046{
2047	struct sockaddr_l2 addr;
2048	struct socket *sock;
2049	struct sock *sk;
2050	struct rfcomm_session *s;
2051	int    err = 0;
2052
2053	/* Create socket */
2054	err = rfcomm_l2sock_create(&sock);
2055	if (err < 0) {
2056		BT_ERR("Create socket failed %d", err);
2057		return err;
2058	}
2059
2060	/* Bind socket */
2061	bacpy(&addr.l2_bdaddr, ba);
2062	addr.l2_family = AF_BLUETOOTH;
2063	addr.l2_psm    = cpu_to_le16(L2CAP_PSM_RFCOMM);
2064	addr.l2_cid    = 0;
2065	addr.l2_bdaddr_type = BDADDR_BREDR;
2066	err = kernel_bind(sock, (struct sockaddr *) &addr, sizeof(addr));
2067	if (err < 0) {
2068		BT_ERR("Bind failed %d", err);
2069		goto failed;
2070	}
2071
2072	/* Set L2CAP options */
2073	sk = sock->sk;
2074	lock_sock(sk);
2075	/* Set MTU to 0 so L2CAP can auto select the MTU */
2076	l2cap_pi(sk)->chan->imtu = 0;
2077	release_sock(sk);
2078
2079	/* Start listening on the socket */
2080	err = kernel_listen(sock, 10);
2081	if (err) {
2082		BT_ERR("Listen failed %d", err);
2083		goto failed;
2084	}
2085
2086	/* Add listening session */
2087	s = rfcomm_session_add(sock, BT_LISTEN);
2088	if (!s) {
2089		err = -ENOMEM;
2090		goto failed;
2091	}
2092
2093	return 0;
2094failed:
2095	sock_release(sock);
2096	return err;
2097}
2098
2099static void rfcomm_kill_listener(void)
2100{
2101	struct rfcomm_session *s, *n;
2102
2103	BT_DBG("");
2104
2105	list_for_each_entry_safe(s, n, &session_list, list)
2106		rfcomm_session_del(s);
2107}
2108
2109static int rfcomm_run(void *unused)
2110{
2111	DEFINE_WAIT_FUNC(wait, woken_wake_function);
2112	BT_DBG("");
2113
2114	set_user_nice(current, -10);
2115
2116	rfcomm_add_listener(BDADDR_ANY);
2117
2118	add_wait_queue(&rfcomm_wq, &wait);
2119	while (!kthread_should_stop()) {
2120
2121		/* Process stuff */
2122		rfcomm_process_sessions();
2123
2124		wait_woken(&wait, TASK_INTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT);
2125	}
2126	remove_wait_queue(&rfcomm_wq, &wait);
2127
2128	rfcomm_kill_listener();
2129
2130	return 0;
2131}
2132
2133static void rfcomm_security_cfm(struct hci_conn *conn, u8 status, u8 encrypt)
2134{
2135	struct rfcomm_session *s;
2136	struct rfcomm_dlc *d, *n;
2137
2138	BT_DBG("conn %p status 0x%02x encrypt 0x%02x", conn, status, encrypt);
2139
2140	s = rfcomm_session_get(&conn->hdev->bdaddr, &conn->dst);
2141	if (!s)
2142		return;
2143
2144	list_for_each_entry_safe(d, n, &s->dlcs, list) {
2145		if (test_and_clear_bit(RFCOMM_SEC_PENDING, &d->flags)) {
2146			rfcomm_dlc_clear_timer(d);
2147			if (status || encrypt == 0x00) {
2148				set_bit(RFCOMM_ENC_DROP, &d->flags);
2149				continue;
2150			}
2151		}
2152
2153		if (d->state == BT_CONNECTED && !status && encrypt == 0x00) {
2154			if (d->sec_level == BT_SECURITY_MEDIUM) {
2155				set_bit(RFCOMM_SEC_PENDING, &d->flags);
2156				rfcomm_dlc_set_timer(d, RFCOMM_AUTH_TIMEOUT);
2157				continue;
2158			} else if (d->sec_level == BT_SECURITY_HIGH ||
2159				   d->sec_level == BT_SECURITY_FIPS) {
2160				set_bit(RFCOMM_ENC_DROP, &d->flags);
2161				continue;
2162			}
2163		}
2164
2165		if (!test_and_clear_bit(RFCOMM_AUTH_PENDING, &d->flags))
2166			continue;
2167
2168		if (!status && hci_conn_check_secure(conn, d->sec_level))
2169			set_bit(RFCOMM_AUTH_ACCEPT, &d->flags);
2170		else
2171			set_bit(RFCOMM_AUTH_REJECT, &d->flags);
2172	}
2173
2174	rfcomm_schedule();
2175}
2176
2177static struct hci_cb rfcomm_cb = {
2178	.name		= "RFCOMM",
2179	.security_cfm	= rfcomm_security_cfm
2180};
2181
2182static int rfcomm_dlc_debugfs_show(struct seq_file *f, void *x)
2183{
2184	struct rfcomm_session *s;
2185
2186	rfcomm_lock();
2187
2188	list_for_each_entry(s, &session_list, list) {
2189		struct l2cap_chan *chan = l2cap_pi(s->sock->sk)->chan;
2190		struct rfcomm_dlc *d;
2191		list_for_each_entry(d, &s->dlcs, list) {
2192			seq_printf(f, "%pMR %pMR %ld %d %d %d %d\n",
2193				   &chan->src, &chan->dst,
2194				   d->state, d->dlci, d->mtu,
2195				   d->rx_credits, d->tx_credits);
2196		}
2197	}
2198
2199	rfcomm_unlock();
2200
2201	return 0;
2202}
2203
2204DEFINE_SHOW_ATTRIBUTE(rfcomm_dlc_debugfs);
2205
2206static struct dentry *rfcomm_dlc_debugfs;
2207
2208/* ---- Initialization ---- */
2209static int __init rfcomm_init(void)
2210{
2211	int err;
2212
2213	hci_register_cb(&rfcomm_cb);
2214
2215	rfcomm_thread = kthread_run(rfcomm_run, NULL, "krfcommd");
2216	if (IS_ERR(rfcomm_thread)) {
2217		err = PTR_ERR(rfcomm_thread);
2218		goto unregister;
2219	}
2220
2221	err = rfcomm_init_ttys();
2222	if (err < 0)
2223		goto stop;
2224
2225	err = rfcomm_init_sockets();
2226	if (err < 0)
2227		goto cleanup;
2228
2229	BT_INFO("RFCOMM ver %s", VERSION);
2230
2231	if (IS_ERR_OR_NULL(bt_debugfs))
2232		return 0;
2233
2234	rfcomm_dlc_debugfs = debugfs_create_file("rfcomm_dlc", 0444,
2235						 bt_debugfs, NULL,
2236						 &rfcomm_dlc_debugfs_fops);
2237
2238	return 0;
2239
2240cleanup:
2241	rfcomm_cleanup_ttys();
2242
2243stop:
2244	kthread_stop(rfcomm_thread);
2245
2246unregister:
2247	hci_unregister_cb(&rfcomm_cb);
2248
2249	return err;
2250}
2251
2252static void __exit rfcomm_exit(void)
2253{
2254	debugfs_remove(rfcomm_dlc_debugfs);
2255
2256	hci_unregister_cb(&rfcomm_cb);
2257
2258	kthread_stop(rfcomm_thread);
2259
2260	rfcomm_cleanup_ttys();
2261
2262	rfcomm_cleanup_sockets();
2263}
2264
2265module_init(rfcomm_init);
2266module_exit(rfcomm_exit);
2267
2268module_param(disable_cfc, bool, 0644);
2269MODULE_PARM_DESC(disable_cfc, "Disable credit based flow control");
2270
2271module_param(channel_mtu, int, 0644);
2272MODULE_PARM_DESC(channel_mtu, "Default MTU for the RFCOMM channel");
2273
2274module_param(l2cap_ertm, bool, 0644);
2275MODULE_PARM_DESC(l2cap_ertm, "Use L2CAP ERTM mode for connection");
2276
2277MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>");
2278MODULE_DESCRIPTION("Bluetooth RFCOMM ver " VERSION);
2279MODULE_VERSION(VERSION);
2280MODULE_LICENSE("GPL");
2281MODULE_ALIAS("bt-proto-3");