core.c 50.5 KB
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/*
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   RFCOMM implementation for Linux Bluetooth stack (BlueZ).
   Copyright (C) 2002 Maxim Krasnyansky <maxk@qualcomm.com>
   Copyright (C) 2002 Marcel Holtmann <marcel@holtmann.org>

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License version 2 as
   published by the Free Software Foundation;

   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
   OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
   FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS.
   IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) AND AUTHOR(S) BE LIABLE FOR ANY
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   CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES
   WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
   ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
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   OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

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   ALL LIABILITY, INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PATENTS,
   COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS, RELATING TO USE OF THIS
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   SOFTWARE IS DISCLAIMED.
*/

/*
 * Bluetooth RFCOMM core.
 */

#include <linux/module.h>
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#include <linux/debugfs.h>
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#include <linux/kthread.h>
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#include <asm/unaligned.h>

#include <net/bluetooth/bluetooth.h>
#include <net/bluetooth/hci_core.h>
#include <net/bluetooth/l2cap.h>
#include <net/bluetooth/rfcomm.h>

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#define VERSION "1.11"
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static bool disable_cfc;
static bool l2cap_ertm;
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static int channel_mtu = -1;
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static unsigned int l2cap_mtu = RFCOMM_MAX_L2CAP_MTU;

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static struct task_struct *rfcomm_thread;

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static DEFINE_MUTEX(rfcomm_mutex);
#define rfcomm_lock()	mutex_lock(&rfcomm_mutex)
#define rfcomm_unlock()	mutex_unlock(&rfcomm_mutex)
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static LIST_HEAD(session_list);

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static int rfcomm_send_frame(struct rfcomm_session *s, u8 *data, int len);
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static int rfcomm_send_sabm(struct rfcomm_session *s, u8 dlci);
static int rfcomm_send_disc(struct rfcomm_session *s, u8 dlci);
static int rfcomm_queue_disc(struct rfcomm_dlc *d);
static int rfcomm_send_nsc(struct rfcomm_session *s, int cr, u8 type);
static int rfcomm_send_pn(struct rfcomm_session *s, int cr, struct rfcomm_dlc *d);
static int rfcomm_send_msc(struct rfcomm_session *s, int cr, u8 dlci, u8 v24_sig);
static int rfcomm_send_test(struct rfcomm_session *s, int cr, u8 *pattern, int len);
static int rfcomm_send_credits(struct rfcomm_session *s, u8 addr, u8 credits);
static void rfcomm_make_uih(struct sk_buff *skb, u8 addr);

static void rfcomm_process_connect(struct rfcomm_session *s);

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static struct rfcomm_session *rfcomm_session_create(bdaddr_t *src,
							bdaddr_t *dst,
							u8 sec_level,
							int *err);
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static struct rfcomm_session *rfcomm_session_get(bdaddr_t *src, bdaddr_t *dst);
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static struct rfcomm_session *rfcomm_session_del(struct rfcomm_session *s);
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/* ---- RFCOMM frame parsing macros ---- */
#define __get_dlci(b)     ((b & 0xfc) >> 2)
#define __get_channel(b)  ((b & 0xf8) >> 3)
#define __get_dir(b)      ((b & 0x04) >> 2)
#define __get_type(b)     ((b & 0xef))

#define __test_ea(b)      ((b & 0x01))
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#define __test_cr(b)      (!!(b & 0x02))
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#define __test_pf(b)      (!!(b & 0x10))
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#define __addr(cr, dlci)       (((dlci & 0x3f) << 2) | (cr << 1) | 0x01)
#define __ctrl(type, pf)       (((type & 0xef) | (pf << 4)))
#define __dlci(dir, chn)       (((chn & 0x1f) << 1) | dir)
#define __srv_channel(dlci)    (dlci >> 1)
#define __dir(dlci)            (dlci & 0x01)

#define __len8(len)       (((len) << 1) | 1)
#define __len16(len)      ((len) << 1)

/* MCC macros */
#define __mcc_type(cr, type)   (((type << 2) | (cr << 1) | 0x01))
#define __get_mcc_type(b) ((b & 0xfc) >> 2)
#define __get_mcc_len(b)  ((b & 0xfe) >> 1)

/* RPN macros */
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#define __rpn_line_settings(data, stop, parity)  ((data & 0x3) | ((stop & 0x1) << 2) | ((parity & 0x7) << 3))
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#define __get_rpn_data_bits(line) ((line) & 0x3)
#define __get_rpn_stop_bits(line) (((line) >> 2) & 0x1)
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#define __get_rpn_parity(line)    (((line) >> 3) & 0x7)
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static void rfcomm_schedule(void)
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{
	if (!rfcomm_thread)
		return;
	wake_up_process(rfcomm_thread);
}

/* ---- RFCOMM FCS computation ---- */

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/* reversed, 8-bit, poly=0x07 */
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static unsigned char rfcomm_crc_table[256] = {
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	0x00, 0x91, 0xe3, 0x72, 0x07, 0x96, 0xe4, 0x75,
	0x0e, 0x9f, 0xed, 0x7c, 0x09, 0x98, 0xea, 0x7b,
	0x1c, 0x8d, 0xff, 0x6e, 0x1b, 0x8a, 0xf8, 0x69,
	0x12, 0x83, 0xf1, 0x60, 0x15, 0x84, 0xf6, 0x67,

	0x38, 0xa9, 0xdb, 0x4a, 0x3f, 0xae, 0xdc, 0x4d,
	0x36, 0xa7, 0xd5, 0x44, 0x31, 0xa0, 0xd2, 0x43,
	0x24, 0xb5, 0xc7, 0x56, 0x23, 0xb2, 0xc0, 0x51,
	0x2a, 0xbb, 0xc9, 0x58, 0x2d, 0xbc, 0xce, 0x5f,

	0x70, 0xe1, 0x93, 0x02, 0x77, 0xe6, 0x94, 0x05,
	0x7e, 0xef, 0x9d, 0x0c, 0x79, 0xe8, 0x9a, 0x0b,
	0x6c, 0xfd, 0x8f, 0x1e, 0x6b, 0xfa, 0x88, 0x19,
	0x62, 0xf3, 0x81, 0x10, 0x65, 0xf4, 0x86, 0x17,

	0x48, 0xd9, 0xab, 0x3a, 0x4f, 0xde, 0xac, 0x3d,
	0x46, 0xd7, 0xa5, 0x34, 0x41, 0xd0, 0xa2, 0x33,
	0x54, 0xc5, 0xb7, 0x26, 0x53, 0xc2, 0xb0, 0x21,
	0x5a, 0xcb, 0xb9, 0x28, 0x5d, 0xcc, 0xbe, 0x2f,

	0xe0, 0x71, 0x03, 0x92, 0xe7, 0x76, 0x04, 0x95,
	0xee, 0x7f, 0x0d, 0x9c, 0xe9, 0x78, 0x0a, 0x9b,
	0xfc, 0x6d, 0x1f, 0x8e, 0xfb, 0x6a, 0x18, 0x89,
	0xf2, 0x63, 0x11, 0x80, 0xf5, 0x64, 0x16, 0x87,

	0xd8, 0x49, 0x3b, 0xaa, 0xdf, 0x4e, 0x3c, 0xad,
	0xd6, 0x47, 0x35, 0xa4, 0xd1, 0x40, 0x32, 0xa3,
	0xc4, 0x55, 0x27, 0xb6, 0xc3, 0x52, 0x20, 0xb1,
	0xca, 0x5b, 0x29, 0xb8, 0xcd, 0x5c, 0x2e, 0xbf,

	0x90, 0x01, 0x73, 0xe2, 0x97, 0x06, 0x74, 0xe5,
	0x9e, 0x0f, 0x7d, 0xec, 0x99, 0x08, 0x7a, 0xeb,
	0x8c, 0x1d, 0x6f, 0xfe, 0x8b, 0x1a, 0x68, 0xf9,
	0x82, 0x13, 0x61, 0xf0, 0x85, 0x14, 0x66, 0xf7,

	0xa8, 0x39, 0x4b, 0xda, 0xaf, 0x3e, 0x4c, 0xdd,
	0xa6, 0x37, 0x45, 0xd4, 0xa1, 0x30, 0x42, 0xd3,
	0xb4, 0x25, 0x57, 0xc6, 0xb3, 0x22, 0x50, 0xc1,
	0xba, 0x2b, 0x59, 0xc8, 0xbd, 0x2c, 0x5e, 0xcf
};

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/* CRC on 2 bytes */
#define __crc(data) (rfcomm_crc_table[rfcomm_crc_table[0xff ^ data[0]] ^ data[1]])

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/* FCS on 2 bytes */
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static inline u8 __fcs(u8 *data)
{
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	return 0xff - __crc(data);
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}

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/* FCS on 3 bytes */
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static inline u8 __fcs2(u8 *data)
{
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	return 0xff - rfcomm_crc_table[__crc(data) ^ data[2]];
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}

/* Check FCS */
static inline int __check_fcs(u8 *data, int type, u8 fcs)
{
	u8 f = __crc(data);

	if (type != RFCOMM_UIH)
		f = rfcomm_crc_table[f ^ data[2]];

	return rfcomm_crc_table[f ^ fcs] != 0xcf;
}

/* ---- L2CAP callbacks ---- */
static void rfcomm_l2state_change(struct sock *sk)
{
	BT_DBG("%p state %d", sk, sk->sk_state);
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	rfcomm_schedule();
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}

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static void rfcomm_l2data_ready(struct sock *sk)
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{
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	BT_DBG("%p", sk);
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	rfcomm_schedule();
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}

static int rfcomm_l2sock_create(struct socket **sock)
{
	int err;

	BT_DBG("");

	err = sock_create_kern(PF_BLUETOOTH, SOCK_SEQPACKET, BTPROTO_L2CAP, sock);
	if (!err) {
		struct sock *sk = (*sock)->sk;
		sk->sk_data_ready   = rfcomm_l2data_ready;
		sk->sk_state_change = rfcomm_l2state_change;
	}
	return err;
}

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static int rfcomm_check_security(struct rfcomm_dlc *d)
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{
	struct sock *sk = d->session->sock->sk;
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	struct l2cap_conn *conn = l2cap_pi(sk)->chan->conn;

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	__u8 auth_type;

	switch (d->sec_level) {
	case BT_SECURITY_HIGH:
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	case BT_SECURITY_FIPS:
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		auth_type = HCI_AT_GENERAL_BONDING_MITM;
		break;
	case BT_SECURITY_MEDIUM:
		auth_type = HCI_AT_GENERAL_BONDING;
		break;
	default:
		auth_type = HCI_AT_NO_BONDING;
		break;
	}
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	return hci_conn_security(conn->hcon, d->sec_level, auth_type,
				 d->out);
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}

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static void rfcomm_session_timeout(unsigned long arg)
{
	struct rfcomm_session *s = (void *) arg;

	BT_DBG("session %p state %ld", s, s->state);

	set_bit(RFCOMM_TIMED_OUT, &s->flags);
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	rfcomm_schedule();
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}

static void rfcomm_session_set_timer(struct rfcomm_session *s, long timeout)
{
	BT_DBG("session %p state %ld timeout %ld", s, s->state, timeout);

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	mod_timer(&s->timer, jiffies + timeout);
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}

static void rfcomm_session_clear_timer(struct rfcomm_session *s)
{
	BT_DBG("session %p state %ld", s, s->state);

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	del_timer_sync(&s->timer);
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}

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/* ---- RFCOMM DLCs ---- */
static void rfcomm_dlc_timeout(unsigned long arg)
{
	struct rfcomm_dlc *d = (void *) arg;

	BT_DBG("dlc %p state %ld", d, d->state);

	set_bit(RFCOMM_TIMED_OUT, &d->flags);
	rfcomm_dlc_put(d);
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	rfcomm_schedule();
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}

static void rfcomm_dlc_set_timer(struct rfcomm_dlc *d, long timeout)
{
	BT_DBG("dlc %p state %ld timeout %ld", d, d->state, timeout);

	if (!mod_timer(&d->timer, jiffies + timeout))
		rfcomm_dlc_hold(d);
}

static void rfcomm_dlc_clear_timer(struct rfcomm_dlc *d)
{
	BT_DBG("dlc %p state %ld", d, d->state);

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	if (del_timer(&d->timer))
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		rfcomm_dlc_put(d);
}

static void rfcomm_dlc_clear_state(struct rfcomm_dlc *d)
{
	BT_DBG("%p", d);

	d->state      = BT_OPEN;
	d->flags      = 0;
	d->mscex      = 0;
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	d->sec_level  = BT_SECURITY_LOW;
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	d->mtu        = RFCOMM_DEFAULT_MTU;
	d->v24_sig    = RFCOMM_V24_RTC | RFCOMM_V24_RTR | RFCOMM_V24_DV;

	d->cfc        = RFCOMM_CFC_DISABLED;
	d->rx_credits = RFCOMM_DEFAULT_CREDITS;
}

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struct rfcomm_dlc *rfcomm_dlc_alloc(gfp_t prio)
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{
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	struct rfcomm_dlc *d = kzalloc(sizeof(*d), prio);

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	if (!d)
		return NULL;

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	setup_timer(&d->timer, rfcomm_dlc_timeout, (unsigned long)d);
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	skb_queue_head_init(&d->tx_queue);
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	mutex_init(&d->lock);
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	atomic_set(&d->refcnt, 1);

	rfcomm_dlc_clear_state(d);
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	BT_DBG("%p", d);
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	return d;
}

void rfcomm_dlc_free(struct rfcomm_dlc *d)
{
	BT_DBG("%p", d);

	skb_queue_purge(&d->tx_queue);
	kfree(d);
}

static void rfcomm_dlc_link(struct rfcomm_session *s, struct rfcomm_dlc *d)
{
	BT_DBG("dlc %p session %p", d, s);

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	rfcomm_session_clear_timer(s);
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	rfcomm_dlc_hold(d);
	list_add(&d->list, &s->dlcs);
	d->session = s;
}

static void rfcomm_dlc_unlink(struct rfcomm_dlc *d)
{
	struct rfcomm_session *s = d->session;

	BT_DBG("dlc %p refcnt %d session %p", d, atomic_read(&d->refcnt), s);

	list_del(&d->list);
	d->session = NULL;
	rfcomm_dlc_put(d);

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	if (list_empty(&s->dlcs))
		rfcomm_session_set_timer(s, RFCOMM_IDLE_TIMEOUT);
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}

static struct rfcomm_dlc *rfcomm_dlc_get(struct rfcomm_session *s, u8 dlci)
{
	struct rfcomm_dlc *d;

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	list_for_each_entry(d, &s->dlcs, list)
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		if (d->dlci == dlci)
			return d;
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	return NULL;
}

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static int rfcomm_check_channel(u8 channel)
{
	return channel < 1 || channel > 30;
}

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static int __rfcomm_dlc_open(struct rfcomm_dlc *d, bdaddr_t *src, bdaddr_t *dst, u8 channel)
{
	struct rfcomm_session *s;
	int err = 0;
	u8 dlci;

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	BT_DBG("dlc %p state %ld %pMR -> %pMR channel %d",
	       d, d->state, src, dst, channel);
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	if (rfcomm_check_channel(channel))
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		return -EINVAL;

	if (d->state != BT_OPEN && d->state != BT_CLOSED)
		return 0;

	s = rfcomm_session_get(src, dst);
	if (!s) {
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		s = rfcomm_session_create(src, dst, d->sec_level, &err);
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		if (!s)
			return err;
	}

	dlci = __dlci(!s->initiator, channel);

	/* Check if DLCI already exists */
	if (rfcomm_dlc_get(s, dlci))
		return -EBUSY;

	rfcomm_dlc_clear_state(d);

	d->dlci     = dlci;
	d->addr     = __addr(s->initiator, dlci);
	d->priority = 7;

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	d->state = BT_CONFIG;
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	rfcomm_dlc_link(s, d);

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	d->out = 1;

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	d->mtu = s->mtu;
	d->cfc = (s->cfc == RFCOMM_CFC_UNKNOWN) ? 0 : s->cfc;

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	if (s->state == BT_CONNECTED) {
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		if (rfcomm_check_security(d))
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			rfcomm_send_pn(s, 1, d);
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		else
			set_bit(RFCOMM_AUTH_PENDING, &d->flags);
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	}

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	rfcomm_dlc_set_timer(d, RFCOMM_CONN_TIMEOUT);
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	return 0;
}

int rfcomm_dlc_open(struct rfcomm_dlc *d, bdaddr_t *src, bdaddr_t *dst, u8 channel)
{
	int r;

	rfcomm_lock();

	r = __rfcomm_dlc_open(d, src, dst, channel);

	rfcomm_unlock();
	return r;
}

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static void __rfcomm_dlc_disconn(struct rfcomm_dlc *d)
{
	struct rfcomm_session *s = d->session;

	d->state = BT_DISCONN;
	if (skb_queue_empty(&d->tx_queue)) {
		rfcomm_send_disc(s, d->dlci);
		rfcomm_dlc_set_timer(d, RFCOMM_DISC_TIMEOUT);
	} else {
		rfcomm_queue_disc(d);
		rfcomm_dlc_set_timer(d, RFCOMM_DISC_TIMEOUT * 2);
	}
}

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static int __rfcomm_dlc_close(struct rfcomm_dlc *d, int err)
{
	struct rfcomm_session *s = d->session;
	if (!s)
		return 0;

	BT_DBG("dlc %p state %ld dlci %d err %d session %p",
			d, d->state, d->dlci, err, s);

	switch (d->state) {
	case BT_CONNECT:
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	case BT_CONFIG:
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	case BT_OPEN:
	case BT_CONNECT2:
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		if (test_and_clear_bit(RFCOMM_DEFER_SETUP, &d->flags)) {
			set_bit(RFCOMM_AUTH_REJECT, &d->flags);
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			rfcomm_schedule();
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			return 0;
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		}
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	}

	switch (d->state) {
	case BT_CONNECT:
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	case BT_CONNECTED:
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		__rfcomm_dlc_disconn(d);
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		break;

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	case BT_CONFIG:
		if (s->state != BT_BOUND) {
			__rfcomm_dlc_disconn(d);
			break;
		}
		/* if closing a dlc in a session that hasn't been started,
		 * just close and unlink the dlc
		 */

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	default:
		rfcomm_dlc_clear_timer(d);

		rfcomm_dlc_lock(d);
		d->state = BT_CLOSED;
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		d->state_change(d, err);
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		rfcomm_dlc_unlock(d);
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		skb_queue_purge(&d->tx_queue);
		rfcomm_dlc_unlink(d);
	}

	return 0;
}

int rfcomm_dlc_close(struct rfcomm_dlc *d, int err)
{
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	int r = 0;
	struct rfcomm_dlc *d_list;
	struct rfcomm_session *s, *s_list;

	BT_DBG("dlc %p state %ld dlci %d err %d", d, d->state, d->dlci, err);
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	rfcomm_lock();

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	s = d->session;
	if (!s)
		goto no_session;

	/* after waiting on the mutex check the session still exists
	 * then check the dlc still exists
	 */
	list_for_each_entry(s_list, &session_list, list) {
		if (s_list == s) {
			list_for_each_entry(d_list, &s->dlcs, list) {
				if (d_list == d) {
					r = __rfcomm_dlc_close(d, err);
					break;
				}
			}
			break;
		}
	}
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no_session:
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	rfcomm_unlock();
	return r;
}

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struct rfcomm_dlc *rfcomm_dlc_exists(bdaddr_t *src, bdaddr_t *dst, u8 channel)
{
	struct rfcomm_session *s;
	struct rfcomm_dlc *dlc = NULL;
	u8 dlci;

	if (rfcomm_check_channel(channel))
		return ERR_PTR(-EINVAL);

	rfcomm_lock();
	s = rfcomm_session_get(src, dst);
	if (s) {
		dlci = __dlci(!s->initiator, channel);
		dlc = rfcomm_dlc_get(s, dlci);
	}
	rfcomm_unlock();
	return dlc;
}

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int rfcomm_dlc_send(struct rfcomm_dlc *d, struct sk_buff *skb)
{
	int len = skb->len;

	if (d->state != BT_CONNECTED)
		return -ENOTCONN;

	BT_DBG("dlc %p mtu %d len %d", d, d->mtu, len);

	if (len > d->mtu)
		return -EINVAL;

	rfcomm_make_uih(skb, d->addr);
	skb_queue_tail(&d->tx_queue, skb);

	if (!test_bit(RFCOMM_TX_THROTTLED, &d->flags))
569
		rfcomm_schedule();
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	return len;
}

573 574 575 576 577 578 579 580 581 582 583 584 585 586
void rfcomm_dlc_send_noerror(struct rfcomm_dlc *d, struct sk_buff *skb)
{
	int len = skb->len;

	BT_DBG("dlc %p mtu %d len %d", d, d->mtu, len);

	rfcomm_make_uih(skb, d->addr);
	skb_queue_tail(&d->tx_queue, skb);

	if (d->state == BT_CONNECTED &&
	    !test_bit(RFCOMM_TX_THROTTLED, &d->flags))
		rfcomm_schedule();
}

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void __rfcomm_dlc_throttle(struct rfcomm_dlc *d)
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{
	BT_DBG("dlc %p state %ld", d, d->state);

	if (!d->cfc) {
		d->v24_sig |= RFCOMM_V24_FC;
		set_bit(RFCOMM_MSC_PENDING, &d->flags);
	}
595
	rfcomm_schedule();
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}

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void __rfcomm_dlc_unthrottle(struct rfcomm_dlc *d)
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{
	BT_DBG("dlc %p state %ld", d, d->state);

	if (!d->cfc) {
		d->v24_sig &= ~RFCOMM_V24_FC;
		set_bit(RFCOMM_MSC_PENDING, &d->flags);
	}
606
	rfcomm_schedule();
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}

609
/*
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   Set/get modem status functions use _local_ status i.e. what we report
   to the other side.
   Remote status is provided by dlc->modem_status() callback.
 */
int rfcomm_dlc_set_modem_status(struct rfcomm_dlc *d, u8 v24_sig)
{
616
	BT_DBG("dlc %p state %ld v24_sig 0x%x",
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			d, d->state, v24_sig);

	if (test_bit(RFCOMM_RX_THROTTLED, &d->flags))
		v24_sig |= RFCOMM_V24_FC;
	else
		v24_sig &= ~RFCOMM_V24_FC;
623

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	d->v24_sig = v24_sig;

	if (!test_and_set_bit(RFCOMM_MSC_PENDING, &d->flags))
627
		rfcomm_schedule();
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	return 0;
}

int rfcomm_dlc_get_modem_status(struct rfcomm_dlc *d, u8 *v24_sig)
{
634
	BT_DBG("dlc %p state %ld v24_sig 0x%x",
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			d, d->state, d->v24_sig);

	*v24_sig = d->v24_sig;
	return 0;
}

/* ---- RFCOMM sessions ---- */
static struct rfcomm_session *rfcomm_session_add(struct socket *sock, int state)
{
644 645
	struct rfcomm_session *s = kzalloc(sizeof(*s), GFP_KERNEL);

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	if (!s)
		return NULL;

	BT_DBG("session %p sock %p", s, sock);

651 652
	setup_timer(&s->timer, rfcomm_session_timeout, (unsigned long) s);

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	INIT_LIST_HEAD(&s->dlcs);
	s->state = state;
	s->sock  = sock;

	s->mtu = RFCOMM_DEFAULT_MTU;
658
	s->cfc = disable_cfc ? RFCOMM_CFC_DISABLED : RFCOMM_CFC_UNKNOWN;
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	/* Do not increment module usage count for listening sessions.
	 * Otherwise we won't be able to unload the module. */
	if (state != BT_LISTEN)
		if (!try_module_get(THIS_MODULE)) {
			kfree(s);
			return NULL;
		}

	list_add(&s->list, &session_list);

	return s;
}

673
static struct rfcomm_session *rfcomm_session_del(struct rfcomm_session *s)
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{
	int state = s->state;

	BT_DBG("session %p state %ld", s, s->state);

	list_del(&s->list);

681
	rfcomm_session_clear_timer(s);
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	sock_release(s->sock);
	kfree(s);

	if (state != BT_LISTEN)
		module_put(THIS_MODULE);
687 688

	return NULL;
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}

static struct rfcomm_session *rfcomm_session_get(bdaddr_t *src, bdaddr_t *dst)
{
	struct rfcomm_session *s;
	struct list_head *p, *n;
695
	struct l2cap_chan *chan;
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	list_for_each_safe(p, n, &session_list) {
		s = list_entry(p, struct rfcomm_session, list);
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		chan = l2cap_pi(s->sock->sk)->chan;
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		if ((!bacmp(src, BDADDR_ANY) || !bacmp(&chan->src, src)) &&
		    !bacmp(&chan->dst, dst))
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			return s;
	}
	return NULL;
}

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static struct rfcomm_session *rfcomm_session_close(struct rfcomm_session *s,
						   int err)
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{
	struct rfcomm_dlc *d;
	struct list_head *p, *n;

	s->state = BT_CLOSED;

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	BT_DBG("session %p state %ld err %d", s, s->state, err);

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	/* Close all dlcs */
	list_for_each_safe(p, n, &s->dlcs) {
		d = list_entry(p, struct rfcomm_dlc, list);
		d->state = BT_CLOSED;
		__rfcomm_dlc_close(d, err);
	}

724
	rfcomm_session_clear_timer(s);
725
	return rfcomm_session_del(s);
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}

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static struct rfcomm_session *rfcomm_session_create(bdaddr_t *src,
							bdaddr_t *dst,
							u8 sec_level,
							int *err)
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{
	struct rfcomm_session *s = NULL;
	struct sockaddr_l2 addr;
	struct socket *sock;
	struct sock *sk;

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	BT_DBG("%pMR -> %pMR", src, dst);
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	*err = rfcomm_l2sock_create(&sock);
	if (*err < 0)
		return NULL;

	bacpy(&addr.l2_bdaddr, src);
	addr.l2_family = AF_BLUETOOTH;
	addr.l2_psm    = 0;
747
	addr.l2_cid    = 0;
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	addr.l2_bdaddr_type = BDADDR_BREDR;
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	*err = kernel_bind(sock, (struct sockaddr *) &addr, sizeof(addr));
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	if (*err < 0)
		goto failed;

	/* Set L2CAP options */
	sk = sock->sk;
	lock_sock(sk);
756
	l2cap_pi(sk)->chan->imtu = l2cap_mtu;
757
	l2cap_pi(sk)->chan->sec_level = sec_level;
758
	if (l2cap_ertm)
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		l2cap_pi(sk)->chan->mode = L2CAP_MODE_ERTM;
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	release_sock(sk);

	s = rfcomm_session_add(sock, BT_BOUND);
	if (!s) {
		*err = -ENOMEM;
		goto failed;
	}

	s->initiator = 1;

	bacpy(&addr.l2_bdaddr, dst);
	addr.l2_family = AF_BLUETOOTH;
772
	addr.l2_psm    = cpu_to_le16(RFCOMM_PSM);
773
	addr.l2_cid    = 0;
774
	addr.l2_bdaddr_type = BDADDR_BREDR;
775
	*err = kernel_connect(sock, (struct sockaddr *) &addr, sizeof(addr), O_NONBLOCK);
776
	if (*err == 0 || *err == -EINPROGRESS)
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		return s;

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	return rfcomm_session_del(s);
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failed:
	sock_release(sock);
	return NULL;
}

void rfcomm_session_getaddr(struct rfcomm_session *s, bdaddr_t *src, bdaddr_t *dst)
{
788
	struct l2cap_chan *chan = l2cap_pi(s->sock->sk)->chan;
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	if (src)
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		bacpy(src, &chan->src);
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	if (dst)
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		bacpy(dst, &chan->dst);
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}

/* ---- RFCOMM frame sending ---- */
796
static int rfcomm_send_frame(struct rfcomm_session *s, u8 *data, int len)
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{
	struct kvec iv = { data, len };
	struct msghdr msg;

801
	BT_DBG("session %p len %d", s, len);
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	memset(&msg, 0, sizeof(msg));

805
	return kernel_sendmsg(s->sock, &msg, &iv, 1, len);
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}

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static int rfcomm_send_cmd(struct rfcomm_session *s, struct rfcomm_cmd *cmd)
{
	BT_DBG("%p cmd %u", s, cmd->ctrl);

812
	return rfcomm_send_frame(s, (void *) cmd, sizeof(*cmd));
813 814
}

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static int rfcomm_send_sabm(struct rfcomm_session *s, u8 dlci)
{
	struct rfcomm_cmd cmd;

	BT_DBG("%p dlci %d", s, dlci);

	cmd.addr = __addr(s->initiator, dlci);
	cmd.ctrl = __ctrl(RFCOMM_SABM, 1);
	cmd.len  = __len8(0);
	cmd.fcs  = __fcs2((u8 *) &cmd);

826
	return rfcomm_send_cmd(s, &cmd);
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}

static int rfcomm_send_ua(struct rfcomm_session *s, u8 dlci)
{
	struct rfcomm_cmd cmd;

	BT_DBG("%p dlci %d", s, dlci);

	cmd.addr = __addr(!s->initiator, dlci);
	cmd.ctrl = __ctrl(RFCOMM_UA, 1);
	cmd.len  = __len8(0);
	cmd.fcs  = __fcs2((u8 *) &cmd);

840
	return rfcomm_send_cmd(s, &cmd);
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}

static int rfcomm_send_disc(struct rfcomm_session *s, u8 dlci)
{
	struct rfcomm_cmd cmd;

	BT_DBG("%p dlci %d", s, dlci);

	cmd.addr = __addr(s->initiator, dlci);
	cmd.ctrl = __ctrl(RFCOMM_DISC, 1);
	cmd.len  = __len8(0);
	cmd.fcs  = __fcs2((u8 *) &cmd);

854
	return rfcomm_send_cmd(s, &cmd);
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}

static int rfcomm_queue_disc(struct rfcomm_dlc *d)
{
	struct rfcomm_cmd *cmd;
	struct sk_buff *skb;

	BT_DBG("dlc %p dlci %d", d, d->dlci);

	skb = alloc_skb(sizeof(*cmd), GFP_KERNEL);
	if (!skb)
		return -ENOMEM;

	cmd = (void *) __skb_put(skb, sizeof(*cmd));
	cmd->addr = d->addr;
	cmd->ctrl = __ctrl(RFCOMM_DISC, 1);
	cmd->len  = __len8(0);
	cmd->fcs  = __fcs2((u8 *) cmd);

	skb_queue_tail(&d->tx_queue, skb);
875
	rfcomm_schedule();
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	return 0;
}

static int rfcomm_send_dm(struct rfcomm_session *s, u8 dlci)
{
	struct rfcomm_cmd cmd;

	BT_DBG("%p dlci %d", s, dlci);

	cmd.addr = __addr(!s->initiator, dlci);
	cmd.ctrl = __ctrl(RFCOMM_DM, 1);
	cmd.len  = __len8(0);
	cmd.fcs  = __fcs2((u8 *) &cmd);

890
	return rfcomm_send_cmd(s, &cmd);
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}

static int rfcomm_send_nsc(struct rfcomm_session *s, int cr, u8 type)
{
	struct rfcomm_hdr *hdr;
	struct rfcomm_mcc *mcc;
	u8 buf[16], *ptr = buf;

	BT_DBG("%p cr %d type %d", s, cr, type);

	hdr = (void *) ptr; ptr += sizeof(*hdr);
	hdr->addr = __addr(s->initiator, 0);
	hdr->ctrl = __ctrl(RFCOMM_UIH, 0);
	hdr->len  = __len8(sizeof(*mcc) + 1);

	mcc = (void *) ptr; ptr += sizeof(*mcc);
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	mcc->type = __mcc_type(0, RFCOMM_NSC);
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	mcc->len  = __len8(1);

	/* Type that we didn't like */
	*ptr = __mcc_type(cr, type); ptr++;

	*ptr = __fcs(buf); ptr++;

915
	return rfcomm_send_frame(s, buf, ptr - buf);
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}

static int rfcomm_send_pn(struct rfcomm_session *s, int cr, struct rfcomm_dlc *d)
{
	struct rfcomm_hdr *hdr;
	struct rfcomm_mcc *mcc;
	struct rfcomm_pn  *pn;
	u8 buf[16], *ptr = buf;

	BT_DBG("%p cr %d dlci %d mtu %d", s, cr, d->dlci, d->mtu);

	hdr = (void *) ptr; ptr += sizeof(*hdr);
	hdr->addr = __addr(s->initiator, 0);
	hdr->ctrl = __ctrl(RFCOMM_UIH, 0);
	hdr->len  = __len8(sizeof(*mcc) + sizeof(*pn));

	mcc = (void *) ptr; ptr += sizeof(*mcc);
	mcc->type = __mcc_type(cr, RFCOMM_PN);
	mcc->len  = __len8(sizeof(*pn));

	pn = (void *) ptr; ptr += sizeof(*pn);
	pn->dlci        = d->dlci;
	pn->priority    = d->priority;
	pn->ack_timer   = 0;
	pn->max_retrans = 0;

	if (s->cfc) {
		pn->flow_ctrl = cr ? 0xf0 : 0xe0;
		pn->credits = RFCOMM_DEFAULT_CREDITS;
	} else {
		pn->flow_ctrl = 0;
		pn->credits   = 0;
	}

950
	if (cr && channel_mtu >= 0)
951
		pn->mtu = cpu_to_le16(channel_mtu);
952
	else
953
		pn->mtu = cpu_to_le16(d->mtu);
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	*ptr = __fcs(buf); ptr++;

957
	return rfcomm_send_frame(s, buf, ptr - buf);
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}

960 961
int rfcomm_send_rpn(struct rfcomm_session *s, int cr, u8 dlci,
			u8 bit_rate, u8 data_bits, u8 stop_bits,
962
			u8 parity, u8 flow_ctrl_settings,
963
			u8 xon_char, u8 xoff_char, u16 param_mask)
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{
	struct rfcomm_hdr *hdr;
	struct rfcomm_mcc *mcc;
	struct rfcomm_rpn *rpn;
	u8 buf[16], *ptr = buf;

	BT_DBG("%p cr %d dlci %d bit_r 0x%x data_b 0x%x stop_b 0x%x parity 0x%x"
971 972
			" flwc_s 0x%x xon_c 0x%x xoff_c 0x%x p_mask 0x%x",
		s, cr, dlci, bit_rate, data_bits, stop_bits, parity,
973
		flow_ctrl_settings, xon_char, xoff_char, param_mask);
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	hdr = (void *) ptr; ptr += sizeof(*hdr);
	hdr->addr = __addr(s->initiator, 0);
	hdr->ctrl = __ctrl(RFCOMM_UIH, 0);
	hdr->len  = __len8(sizeof(*mcc) + sizeof(*rpn));

	mcc = (void *) ptr; ptr += sizeof(*mcc);
	mcc->type = __mcc_type(cr, RFCOMM_RPN);
	mcc->len  = __len8(sizeof(*rpn));

	rpn = (void *) ptr; ptr += sizeof(*rpn);
	rpn->dlci          = __addr(1, dlci);
	rpn->bit_rate      = bit_rate;
	rpn->line_settings = __rpn_line_settings(data_bits, stop_bits, parity);
	rpn->flow_ctrl     = flow_ctrl_settings;
	rpn->xon_char      = xon_char;
	rpn->xoff_char     = xoff_char;
991
	rpn->param_mask    = cpu_to_le16(param_mask);
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	*ptr = __fcs(buf); ptr++;

995
	return rfcomm_send_frame(s, buf, ptr - buf);
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}

static int rfcomm_send_rls(struct rfcomm_session *s, int cr, u8 dlci, u8 status)
{
	struct rfcomm_hdr *hdr;
	struct rfcomm_mcc *mcc;
	struct rfcomm_rls *rls;
	u8 buf[16], *ptr = buf;

	BT_DBG("%p cr %d status 0x%x", s, cr, status);

	hdr = (void *) ptr; ptr += sizeof(*hdr);
	hdr->addr = __addr(s->initiator, 0);
	hdr->ctrl = __ctrl(RFCOMM_UIH, 0);
	hdr->len  = __len8(sizeof(*mcc) + sizeof(*rls));

	mcc = (void *) ptr; ptr += sizeof(*mcc);
	mcc->type = __mcc_type(cr, RFCOMM_RLS);
	mcc->len  = __len8(sizeof(*rls));

	rls = (void *) ptr; ptr += sizeof(*rls);
	rls->dlci   = __addr(1, dlci);
	rls->status = status;

	*ptr = __fcs(buf); ptr++;

1022
	return rfcomm_send_frame(s, buf, ptr - buf);
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}

static int rfcomm_send_msc(struct rfcomm_session *s, int cr, u8 dlci, u8 v24_sig)
{
	struct rfcomm_hdr *hdr;
	struct rfcomm_mcc *mcc;
	struct rfcomm_msc *msc;
	u8 buf[16], *ptr = buf;

	BT_DBG("%p cr %d v24 0x%x", s, cr, v24_sig);

	hdr = (void *) ptr; ptr += sizeof(*hdr);
	hdr->addr = __addr(s->initiator, 0);
	hdr->ctrl = __ctrl(RFCOMM_UIH, 0);
	hdr->len  = __len8(sizeof(*mcc) + sizeof(*msc));

	mcc = (void *) ptr; ptr += sizeof(*mcc);
	mcc->type = __mcc_type(cr, RFCOMM_MSC);
	mcc->len  = __len8(sizeof(*msc));

	msc = (void *) ptr; ptr += sizeof(*msc);
	msc->dlci    = __addr(1, dlci);
	msc->v24_sig = v24_sig | 0x01;

	*ptr = __fcs(buf); ptr++;

1049
	return rfcomm_send_frame(s, buf, ptr - buf);
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}

static int rfcomm_send_fcoff(struct rfcomm_session *s, int cr)
{
	struct rfcomm_hdr *hdr;
	struct rfcomm_mcc *mcc;
	u8 buf[16], *ptr = buf;

	BT_DBG("%p cr %d", s, cr);

	hdr = (void *) ptr; ptr += sizeof(*hdr);
	hdr->addr = __addr(s->initiator, 0);
	hdr->ctrl = __ctrl(RFCOMM_UIH, 0);
	hdr->len  = __len8(sizeof(*mcc));

	mcc = (void *) ptr; ptr += sizeof(*mcc);
	mcc->type = __mcc_type(cr, RFCOMM_FCOFF);
	mcc->len  = __len8(0);

	*ptr = __fcs(buf); ptr++;

1071
	return rfcomm_send_frame(s, buf, ptr - buf);
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}

static int rfcomm_send_fcon(struct rfcomm_session *s, int cr)
{
	struct rfcomm_hdr *hdr;
	struct rfcomm_mcc *mcc;
	u8 buf[16], *ptr = buf;

	BT_DBG("%p cr %d", s, cr);

	hdr = (void *) ptr; ptr += sizeof(*hdr);
	hdr->addr = __addr(s->initiator, 0);
	hdr->ctrl = __ctrl(RFCOMM_UIH, 0);
	hdr->len  = __len8(sizeof(*mcc));

	mcc = (void *) ptr; ptr += sizeof(*mcc);
	mcc->type = __mcc_type(cr, RFCOMM_FCON);
	mcc->len  = __len8(0);

	*ptr = __fcs(buf); ptr++;

1093
	return rfcomm_send_frame(s, buf, ptr - buf);
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}

static int rfcomm_send_test(struct rfcomm_session *s, int cr, u8 *pattern, int len)
{
	struct socket *sock = s->sock;
	struct kvec iv[3];
	struct msghdr msg;
	unsigned char hdr[5], crc[1];

	if (len > 125)
		return -EINVAL;

	BT_DBG("%p cr %d", s, cr);

	hdr[0] = __addr(s->initiator, 0);
	hdr[1] = __ctrl(RFCOMM_UIH, 0);
	hdr[2] = 0x01 | ((len + 2) << 1);
	hdr[3] = 0x01 | ((cr & 0x01) << 1) | (RFCOMM_TEST << 2);
	hdr[4] = 0x01 | (len << 1);

	crc[0] = __fcs(hdr);

	iv[0].iov_base = hdr;
	iv[0].iov_len  = 5;
	iv[1].iov_base = pattern;
	iv[1].iov_len  = len;
	iv[2].iov_base = crc;
	iv[2].iov_len  = 1;

	memset(&msg, 0, sizeof(msg));

	return kernel_sendmsg(sock, &msg, iv, 3, 6 + len);
}

static int rfcomm_send_credits(struct rfcomm_session *s, u8 addr, u8 credits)
{
	struct rfcomm_hdr *hdr;
	u8 buf[16], *ptr = buf;

	BT_DBG("%p addr %d credits %d", s, addr, credits);

	hdr = (void *) ptr; ptr += sizeof(*hdr);
	hdr->addr = addr;
	hdr->ctrl = __ctrl(RFCOMM_UIH, 1);
	hdr->len  = __len8(0);

	*ptr = credits; ptr++;

	*ptr = __fcs(buf); ptr++;

1144
	return rfcomm_send_frame(s, buf, ptr - buf);
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}

static void rfcomm_make_uih(struct sk_buff *skb, u8 addr)
{
	struct rfcomm_hdr *hdr;
	int len = skb->len;
	u8 *crc;

	if (len > 127) {
		hdr = (void *) skb_push(skb, 4);
1155
		put_unaligned(cpu_to_le16(__len16(len)), (__le16 *) &hdr->len);
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	} else {
		hdr = (void *) skb_push(skb, 3);
		hdr->len = __len8(len);
	}
	hdr->addr = addr;
	hdr->ctrl = __ctrl(RFCOMM_UIH, 0);

	crc = skb_put(skb, 1);
	*crc = __fcs((void *) hdr);
}

/* ---- RFCOMM frame reception ---- */
1168
static struct rfcomm_session *rfcomm_recv_ua(struct rfcomm_session *s, u8 dlci)
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{
	BT_DBG("session %p state %ld dlci %d", s, s->state, dlci);

	if (dlci) {
		/* Data channel */
		struct rfcomm_dlc *d = rfcomm_dlc_get(s, dlci);
		if (!d) {
			rfcomm_send_dm(s, dlci);
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			return s;
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		}

		switch (d->state) {
		case BT_CONNECT:
			rfcomm_dlc_clear_timer(d);

			rfcomm_dlc_lock(d);
			d->state = BT_CONNECTED;
			d->state_change(d, 0);
			rfcomm_dlc_unlock(d);

			rfcomm_send_msc(s, 1, dlci, d->v24_sig);
			break;

		case BT_DISCONN:
			d->state = BT_CLOSED;
			__rfcomm_dlc_close(d, 0);
1195 1196 1197 1198

			if (list_empty(&s->dlcs)) {
				s->state = BT_DISCONN;
				rfcomm_send_disc(s, 0);
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				rfcomm_session_clear_timer(s);
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			}

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			break;
		}
	} else {
		/* Control channel */
		switch (s->state) {
		case BT_CONNECT:
			s->state = BT_CONNECTED;
			rfcomm_process_connect(s);
			break;
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		case BT_DISCONN:
1213
			s = rfcomm_session_close(s, ECONNRESET);
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			break;
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		}
	}
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	return s;
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}

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static struct rfcomm_session *rfcomm_recv_dm(struct rfcomm_session *s, u8 dlci)
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{
	int err = 0;

	BT_DBG("session %p state %ld dlci %d", s, s->state, dlci);

	if (dlci) {
		/* Data DLC */
		struct rfcomm_dlc *d = rfcomm_dlc_get(s, dlci);
		if (d) {
			if (d->state == BT_CONNECT || d->state == BT_CONFIG)
				err = ECONNREFUSED;
			else
				err = ECONNRESET;

			d->state = BT_CLOSED;
			__rfcomm_dlc_close(d, err);
		}
	} else {
		if (s->state == BT_CONNECT)
			err = ECONNREFUSED;
		else
			err = ECONNRESET;

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		s = rfcomm_session_close(s, err);
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	}
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	return s;
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}

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static struct rfcomm_session *rfcomm_recv_disc(struct rfcomm_session *s,
					       u8 dlci)
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{
	int err = 0;

	BT_DBG("session %p state %ld dlci %d", s, s->state, dlci);

	if (dlci) {
		struct rfcomm_dlc *d = rfcomm_dlc_get(s, dlci);
		if (d) {
			rfcomm_send_ua(s, dlci);

			if (d->state == BT_CONNECT || d->state == BT_CONFIG)
				err = ECONNREFUSED;
			else
				err = ECONNRESET;

			d->state = BT_CLOSED;
			__rfcomm_dlc_close(d, err);
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		} else
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			rfcomm_send_dm(s, dlci);
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	} else {
		rfcomm_send_ua(s, 0);

		if (s->state == BT_CONNECT)
			err = ECONNREFUSED;
		else
			err = ECONNRESET;

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		s = rfcomm_session_close(s, err);
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	}
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	return s;
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}

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void rfcomm_dlc_accept(struct rfcomm_dlc *d)
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{
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	struct sock *sk = d->session->sock->sk;
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	struct l2cap_conn *conn = l2cap_pi(sk)->chan->conn;
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	BT_DBG("dlc %p", d);

	rfcomm_send_ua(d->session, d->dlci);

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	rfcomm_dlc_clear_timer(d);

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	rfcomm_dlc_lock(d);
	d->state = BT_CONNECTED;
	d->state_change(d, 0);
	rfcomm_dlc_unlock(d);

1300
	if (d->role_switch)
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		hci_conn_switch_role(conn->hcon, 0x00);
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	rfcomm_send_msc(d->session, 1, d->dlci, d->v24_sig);
}

1306 1307
static void rfcomm_check_accept(struct rfcomm_dlc *d)
{
1308
	if (rfcomm_check_security(d)) {
1309 1310 1311
		if (d->defer_setup) {
			set_bit(RFCOMM_DEFER_SETUP, &d->flags);
			rfcomm_dlc_set_timer(d, RFCOMM_AUTH_TIMEOUT);
1312 1313 1314 1315 1316

			rfcomm_dlc_lock(d);
			d->state = BT_CONNECT2;
			d->state_change(d, 0);
			rfcomm_dlc_unlock(d);
1317 1318
		} else
			rfcomm_dlc_accept(d);
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	} else {
		set_bit(RFCOMM_AUTH_PENDING, &d->flags);
		rfcomm_dlc_set_timer(d, RFCOMM_AUTH_TIMEOUT);
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	}
}

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static int rfcomm_recv_sabm(struct rfcomm_session *s, u8 dlci)
{
	struct rfcomm_dlc *d;
	u8 channel;

	BT_DBG("session %p state %ld dlci %d", s, s->state, dlci);

	if (!dlci) {
		rfcomm_send_ua(s, 0);

		if (s->state == BT_OPEN) {
			s->state = BT_CONNECTED;
			rfcomm_process_connect(s);
		}
		return 0;
	}

	/* Check if DLC exists */
	d = rfcomm_dlc_get(s, dlci);
	if (d) {
		if (d->state == BT_OPEN) {
			/* DLC was previously opened by PN request */
1347
			rfcomm_check_accept(d);
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		}
		return 0;
	}

	/* Notify socket layer about incoming connection */
	channel = __srv_channel(dlci);
	if (rfcomm_connect_ind(s, channel, &d)) {
		d->dlci = dlci;
		d->addr = __addr(s->initiator, dlci);
		rfcomm_dlc_link(s, d);

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		rfcomm_check_accept(d);
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	} else {
		rfcomm_send_dm(s, dlci);
	}

	return 0;
}

static int rfcomm_apply_pn(struct rfcomm_dlc *d, int cr, struct rfcomm_pn *pn)
{
	struct rfcomm_session *s = d->session;

1371
	BT_DBG("dlc %p state %ld dlci %d mtu %d fc 0x%x credits %d",
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			d, d->state, d->dlci, pn->mtu, pn->flow_ctrl, pn->credits);

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	if ((pn->flow_ctrl == 0xf0 && s->cfc != RFCOMM_CFC_DISABLED) ||
						pn->flow_ctrl == 0xe0) {
		d->cfc = RFCOMM_CFC_ENABLED;
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		d->tx_credits = pn->credits;
	} else {
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		d->cfc = RFCOMM_CFC_DISABLED;
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		set_bit(RFCOMM_TX_THROTTLED, &d->flags);
	}

1383 1384 1385
	if (s->cfc == RFCOMM_CFC_UNKNOWN)
		s->cfc = d->cfc;

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	d->priority = pn->priority;

1388
	d->mtu = __le16_to_cpu(pn->mtu);
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	if (cr && d->mtu > s->mtu)
		d->mtu = s->mtu;
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	return 0;
}

static int rfcomm_recv_pn(struct rfcomm_session *s, int cr, struct sk_buff *skb)
{
	struct rfcomm_pn *pn = (void *) skb->data;
	struct rfcomm_dlc *d;
	u8 dlci = pn->dlci;

	BT_DBG("session %p state %ld dlci %d", s, s->state, dlci);

	if (!dlci)
		return 0;

	d = rfcomm_dlc_get(s, dlci);
	if (d) {
		if (cr) {
			/* PN request */
			rfcomm_apply_pn(d, cr, pn);
			rfcomm_send_pn(s, 0, d);
		} else {
			/* PN response */
			switch (d->state) {
			case BT_CONFIG:
				rfcomm_apply_pn(d, cr, pn);

				d->state = BT_CONNECT;
				rfcomm_send_sabm(s, d->dlci);
				break;
			}
		}
	} else {
		u8 channel = __srv_channel(dlci);

		if (!cr)
			return 0;

		/* PN request for non existing DLC.
		 * Assume incoming connection. */
		if (rfcomm_connect_ind(s, channel, &d)) {
			d->dlci = dlci;
			d->addr = __addr(s->initiator, dlci);
			rfcomm_dlc_link(s, d);

			rfcomm_apply_pn(d, cr, pn);

			d->state = BT_OPEN;
			rfcomm_send_pn(s, 0, d);
		} else {
			rfcomm_send_dm(s, dlci);
		}
	}
	return 0;
}

static int rfcomm_recv_rpn(struct rfcomm_session *s, int cr, int len, struct sk_buff *skb)
{
	struct rfcomm_rpn *rpn = (void *) skb->data;
	u8 dlci = __get_dlci(rpn->dlci);

	u8 bit_rate  = 0;
	u8 data_bits = 0;
	u8 stop_bits = 0;
	u8 parity    = 0;
	u8 flow_ctrl = 0;
	u8 xon_char  = 0;
	u8 xoff_char = 0;
	u16 rpn_mask = RFCOMM_RPN_PM_ALL;
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	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",
		dlci, cr, len, rpn->bit_rate, rpn->line_settings, rpn->flow_ctrl,
		rpn->xon_char, rpn->xoff_char, rpn->param_mask);

	if (!cr)
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		return 0;
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	if (len == 1) {
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		/* This is a request, return default (according to ETSI TS 07.10) settings */
		bit_rate  = RFCOMM_RPN_BR_9600;
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		data_bits = RFCOMM_RPN_DATA_8;
		stop_bits = RFCOMM_RPN_STOP_1;
		parity    = RFCOMM_RPN_PARITY_NONE;
		flow_ctrl = RFCOMM_RPN_FLOW_NONE;
		xon_char  = RFCOMM_RPN_XON_CHAR;
		xoff_char = RFCOMM_RPN_XOFF_CHAR;
		goto rpn_out;
	}
1480 1481 1482 1483

	/* Check for sane values, ignore/accept bit_rate, 8 bits, 1 stop bit,
	 * no parity, no flow control lines, normal XON/XOFF chars */

1484
	if (rpn->param_mask & cpu_to_le16(RFCOMM_RPN_PM_BITRATE)) {
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		bit_rate = rpn->bit_rate;
1486
		if (bit_rate > RFCOMM_RPN_BR_230400) {
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			BT_DBG("RPN bit rate mismatch 0x%x", bit_rate);
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			bit_rate = RFCOMM_RPN_BR_9600;
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			rpn_mask ^= RFCOMM_RPN_PM_BITRATE;
		}
	}
1492

1493
	if (rpn->param_mask & cpu_to_le16(RFCOMM_RPN_PM_DATA)) {
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		data_bits = __get_rpn_data_bits(rpn->line_settings);
		if (data_bits != RFCOMM_RPN_DATA_8) {
			BT_DBG("RPN data bits mismatch 0x%x", data_bits);
			data_bits = RFCOMM_RPN_DATA_8;
			rpn_mask ^= RFCOMM_RPN_PM_DATA;
		}
	}
1501

1502
	if (rpn->param_mask & cpu_to_le16(RFCOMM_RPN_PM_STOP)) {
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		stop_bits = __get_rpn_stop_bits(rpn->line_settings);
		if (stop_bits != RFCOMM_RPN_STOP_1) {
			BT_DBG("RPN stop bits mismatch 0x%x", stop_bits);
			stop_bits = RFCOMM_RPN_STOP_1;
			rpn_mask ^= RFCOMM_RPN_PM_STOP;
		}
	}
1510

1511
	if (rpn->param_mask & cpu_to_le16(RFCOMM_RPN_PM_PARITY)) {
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		parity = __get_rpn_parity(rpn->line_settings);
		if (parity != RFCOMM_RPN_PARITY_NONE) {
			BT_DBG("RPN parity mismatch 0x%x", parity);
			parity = RFCOMM_RPN_PARITY_NONE;
			rpn_mask ^= RFCOMM_RPN_PM_PARITY;
		}
	}
1519

1520
	if (rpn->param_mask & cpu_to_le16(RFCOMM_RPN_PM_FLOW)) {
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		flow_ctrl = rpn->flow_ctrl;
		if (flow_ctrl != RFCOMM_RPN_FLOW_NONE) {
			BT_DBG("RPN flow ctrl mismatch 0x%x", flow_ctrl);
			flow_ctrl = RFCOMM_RPN_FLOW_NONE;
			rpn_mask ^= RFCOMM_RPN_PM_FLOW;
		}
	}
1528

1529
	if (rpn->param_mask & cpu_to_le16(RFCOMM_RPN_PM_XON)) {
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		xon_char = rpn->xon_char;
		if (xon_char != RFCOMM_RPN_XON_CHAR) {
			BT_DBG("RPN XON char mismatch 0x%x", xon_char);
			xon_char = RFCOMM_RPN_XON_CHAR;
			rpn_mask ^= RFCOMM_RPN_PM_XON;
		}
	}
1537

1538
	if (rpn->param_mask & cpu_to_le16(RFCOMM_RPN_PM_XOFF)) {
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		xoff_char = rpn->xoff_char;
		if (xoff_char != RFCOMM_RPN_XOFF_CHAR) {
			BT_DBG("RPN XOFF char mismatch 0x%x", xoff_char);
			xoff_char = RFCOMM_RPN_XOFF_CHAR;
			rpn_mask ^= RFCOMM_RPN_PM_XOFF;
		}
	}

rpn_out:
1548 1549
	rfcomm_send_rpn(s, 0, dlci, bit_rate, data_bits, stop_bits,
			parity, flow_ctrl, xon_char, xoff_char, rpn_mask);
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	return 0;
}

static int rfcomm_recv_rls(struct rfcomm_session *s, int cr, struct sk_buff *skb)
{
	struct rfcomm_rls *rls = (void *) skb->data;
	u8 dlci = __get_dlci(rls->dlci);

	BT_DBG("dlci %d cr %d status 0x%x", dlci, cr, rls->status);
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	if (!cr)
		return 0;

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	/* We should probably do something with this information here. But
	 * for now it's sufficient just to reply -- Bluetooth 1.1 says it's
	 * mandatory to recognise and respond to RLS */
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	rfcomm_send_rls(s, 0, dlci, rls->status);

	return 0;
}

static int rfcomm_recv_msc(struct rfcomm_session *s, int cr, struct sk_buff *skb)
{
	struct rfcomm_msc *msc = (void *) skb->data;
	struct rfcomm_dlc *d;
	u8 dlci = __get_dlci(msc->dlci);

	BT_DBG("dlci %d cr %d v24 0x%x", dlci, cr, msc->v24_sig);

	d = rfcomm_dlc_get(s, dlci);
1582
	if (!d)
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		return 0;

	if (cr) {
		if (msc->v24_sig & RFCOMM_V24_FC && !d->cfc)
			set_bit(RFCOMM_TX_THROTTLED, &d->flags);
		else
			clear_bit(RFCOMM_TX_THROTTLED, &d->flags);
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		rfcomm_dlc_lock(d);
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		d->remote_v24_sig = msc->v24_sig;

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		if (d->modem_status)
			d->modem_status(d, msc->v24_sig);
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		rfcomm_dlc_unlock(d);
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		rfcomm_send_msc(s, 0, dlci, msc->v24_sig);

		d->mscex |= RFCOMM_MSCEX_RX;
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	} else
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		d->mscex |= RFCOMM_MSCEX_TX;

	return 0;
}

static int rfcomm_recv_mcc(struct rfcomm_session *s, struct sk_buff *skb)
{
	struct rfcomm_mcc *mcc = (void *) skb->data;
	u8 type, cr, len;

	cr   = __test_cr(mcc->type);
	type = __get_mcc_type(mcc->type);
	len  = __get_mcc_len(mcc->len);

	BT_DBG("%p type 0x%x cr %d", s, type, cr);

	skb_pull(skb, 2);

	switch (type) {
	case RFCOMM_PN:
		rfcomm_recv_pn(s, cr, skb);
		break;

	case RFCOMM_RPN:
		rfcomm_recv_rpn(s, cr, len, skb);
		break;

	case RFCOMM_RLS:
		rfcomm_recv_rls(s, cr, skb);
		break;

	case RFCOMM_MSC:
		rfcomm_recv_msc(s, cr, skb);
		break;

	case RFCOMM_FCOFF:
		if (cr) {
			set_bit(RFCOMM_TX_THROTTLED, &s->flags);
			rfcomm_send_fcoff(s, 0);
		}
		break;

	case RFCOMM_FCON:
		if (cr) {
			clear_bit(RFCOMM_TX_THROTTLED, &s->flags);
			rfcomm_send_fcon(s, 0);
		}
		break;

	case RFCOMM_TEST:
		if (cr)
			rfcomm_send_test(s, 0, skb->data, skb->len);
		break;

	case RFCOMM_NSC:
		break;

	default:
		BT_ERR("Unknown control type 0x%02x", type);
		rfcomm_send_nsc(s, cr, type);
		break;
	}
	return 0;
}

static int rfcomm_recv_data(struct rfcomm_session *s, u8 dlci, int pf, struct sk_buff *skb)
{
	struct rfcomm_dlc *d;

	BT_DBG("session %p state %ld dlci %d pf %d", s, s->state, dlci, pf);

	d = rfcomm_dlc_get(s, dlci);
	if (!d) {
		rfcomm_send_dm(s, dlci);
		goto drop;
	}

	if (pf && d->cfc) {
		u8 credits = *(u8 *) skb->data; skb_pull(skb, 1);

		d->tx_credits += credits;
		if (d->tx_credits)
			clear_bit(RFCOMM_TX_THROTTLED, &d->flags);
	}

	if (skb->len && d->state == BT_CONNECTED) {
		rfcomm_dlc_lock(d);
		d->rx_credits--;
		d->data_ready(d, skb);
		rfcomm_dlc_unlock(d);
		return 0;
	}

drop:
	kfree_skb(skb);
	return 0;
}

1702 1703
static struct rfcomm_session *rfcomm_recv_frame(struct rfcomm_session *s,
						struct sk_buff *skb)
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{
	struct rfcomm_hdr *hdr = (void *) skb->data;
	u8 type, dlci, fcs;

1708 1709 1710 1711 1712 1713
	if (!s) {
		/* no session, so free socket data */
		kfree_skb(skb);
		return s;
	}

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	dlci = __get_dlci(hdr->addr);
	type = __get_type(hdr->ctrl);

	/* Trim FCS */
	skb->len--; skb->tail--;
1719
	fcs = *(u8 *)skb_tail_pointer(skb);
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	if (__check_fcs(skb->data, type, fcs)) {
		BT_ERR("bad checksum in packet");
		kfree_skb(skb);
1724
		return s;
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	}

	if (__test_ea(hdr->len))
		skb_pull(skb, 3);
	else
		skb_pull(skb, 4);

	switch (type) {
	case RFCOMM_SABM:
		if (__test_pf(hdr->ctrl))
			rfcomm_recv_sabm(s, dlci);
		break;

	case RFCOMM_DISC:
		if (__test_pf(hdr->ctrl))
1740
			s = rfcomm_recv_disc(s, dlci);
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		break;

	case RFCOMM_UA:
		if (__test_pf(hdr->ctrl))
1745
			s = rfcomm_recv_ua(s, dlci);
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		break;

	case RFCOMM_DM:
1749
		s = rfcomm_recv_dm(s, dlci);
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		break;

	case RFCOMM_UIH:
1753 1754 1755 1756
		if (dlci) {
			rfcomm_recv_data(s, dlci, __test_pf(hdr->ctrl), skb);
			return s;
		}
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		rfcomm_recv_mcc(s, skb);
		break;

	default:
1761
		BT_ERR("Unknown packet type 0x%02x", type);
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		break;
	}
	kfree_skb(skb);
1765
	return s;
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}

/* ---- Connection and data processing ---- */

static void rfcomm_process_connect(struct rfcomm_session *s)
{
	struct rfcomm_dlc *d;
	struct list_head *p, *n;

	BT_DBG("session %p state %ld", s, s->state);

	list_for_each_safe(p, n, &s->dlcs) {
		d = list_entry(p, struct rfcomm_dlc, list);
		if (d->state == BT_CONFIG) {
			d->mtu = s->mtu;
1781
			if (rfcomm_check_security(d)) {
1782 1783
				rfcomm_send_pn(s, 1, d);
			} else {
1784 1785
				set_bit(RFCOMM_AUTH_PENDING, &d->flags);
				rfcomm_dlc_set_timer(d, RFCOMM_AUTH_TIMEOUT);
1786
			}
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		}
	}
}

/* Send data queued for the DLC.
 * Return number of frames left in the queue.
 */
1794
static int rfcomm_process_tx(struct rfcomm_dlc *d)
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{
	struct sk_buff *skb;
	int err;

1799
	BT_DBG("dlc %p state %ld cfc %d rx_credits %d tx_credits %d",
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			d, d->state, d->cfc, d->rx_credits, d->tx_credits);

	/* Send pending MSC */
	if (test_and_clear_bit(RFCOMM_MSC_PENDING, &d->flags))
1804
		rfcomm_send_msc(d->session, 1, d->dlci, d->v24_sig);
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	if (d->cfc) {
1807
		/* CFC enabled.
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		 * Give them some credits */
		if (!test_bit(RFCOMM_RX_THROTTLED, &d->flags) &&
1810
				d->rx_credits <= (d->cfc >> 2)) {
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			rfcomm_send_credits(d->session, d->addr, d->cfc - d->rx_credits);
			d->rx_credits = d->cfc;
		}
	} else {
		/* CFC disabled.
		 * Give ourselves some credits */
		d->tx_credits = 5;
	}

	if (test_bit(RFCOMM_TX_THROTTLED, &d->flags))
		return skb_queue_len(&d->tx_queue);

	while (d->tx_credits && (skb = skb_dequeue(&d->tx_queue))) {
1824
		err = rfcomm_send_frame(d->session, skb->data, skb->len);
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		if (err < 0) {
			skb_queue_head(&d->tx_queue, skb);
			break;
		}
		kfree_skb(skb);
		d->tx_credits--;
	}

	if (d->cfc && !d->tx_credits) {
		/* We're out of TX credits.
		 * Set TX_THROTTLED flag to avoid unnesary wakeups by dlc_send. */
		set_bit(RFCOMM_TX_THROTTLED, &d->flags);
	}

	return skb_queue_len(&d->tx_queue);
}

1842
static void rfcomm_process_dlcs(struct rfcomm_session *s)
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1843 1844 1845 1846 1847 1848 1849 1850 1851 1852 1853 1854 1855 1856
{
	struct rfcomm_dlc *d;
	struct list_head *p, *n;

	BT_DBG("session %p state %ld", s, s->state);

	list_for_each_safe(p, n, &s->dlcs) {
		d = list_entry(p, struct rfcomm_dlc, list);

		if (test_bit(RFCOMM_TIMED_OUT, &d->flags)) {
			__rfcomm_dlc_close(d, ETIMEDOUT);
			continue;
		}

1857 1858 1859 1860 1861
		if (test_bit(RFCOMM_ENC_DROP, &d->flags)) {
			__rfcomm_dlc_close(d, ECONNREFUSED);
			continue;
		}

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		if (test_and_clear_bit(RFCOMM_AUTH_ACCEPT, &d->flags)) {
			rfcomm_dlc_clear_timer(d);
1864 1865 1866
			if (d->out) {
				rfcomm_send_pn(s, 1, d);
				rfcomm_dlc_set_timer(d, RFCOMM_CONN_TIMEOUT);
1867 1868 1869 1870
			} else {
				if (d->defer_setup) {
					set_bit(RFCOMM_DEFER_SETUP, &d->flags);
					rfcomm_dlc_set_timer(d, RFCOMM_AUTH_TIMEOUT);
1871 1872 1873 1874 1875

					rfcomm_dlc_lock(d);
					d->state = BT_CONNECT2;
					d->state_change(d, 0);
					rfcomm_dlc_unlock(d);
1876 1877 1878
				} else
					rfcomm_dlc_accept(d);
			}
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			continue;
		} else if (test_and_clear_bit(RFCOMM_AUTH_REJECT, &d->flags)) {
			rfcomm_dlc_clear_timer(d);
1882 1883 1884 1885
			if (!d->out)
				rfcomm_send_dm(s, d->dlci);
			else
				d->state = BT_CLOSED;
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			__rfcomm_dlc_close(d, ECONNREFUSED);
			continue;
		}

1890 1891 1892
		if (test_bit(RFCOMM_SEC_PENDING, &d->flags))
			continue;

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		if (test_bit(RFCOMM_TX_THROTTLED, &s->flags))
			continue;

		if ((d->state == BT_CONNECTED || d->state == BT_DISCONN) &&
1897
						d->mscex == RFCOMM_MSCEX_OK)
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			rfcomm_process_tx(d);
	}
}

1902
static struct rfcomm_session *rfcomm_process_rx(struct rfcomm_session *s)
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{
	struct socket *sock = s->sock;
	struct sock *sk = sock->sk;
	struct sk_buff *skb;

	BT_DBG("session %p state %ld qlen %d", s, s->state, skb_queue_len(&sk->sk_receive_queue));

	/* Get data directly from socket receive queue without copying it. */
	while ((skb = skb_dequeue(&sk->sk_receive_queue))) {
		skb_orphan(skb);
1913
		if (!skb_linearize(skb)) {
1914
			s = rfcomm_recv_frame(s, skb);
1915 1916 1917
			if (!s)
				break;
		} else {
1918
			kfree_skb(skb);
1919
		}
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	}

1922 1923
	if (s && (sk->sk_state == BT_CLOSED))
		s = rfcomm_session_close(s, sk->sk_err);
1924 1925

	return s;
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}

1928
static void rfcomm_accept_connection(struct rfcomm_session *s)
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1929 1930 1931 1932 1933 1934 1935 1936 1937 1938 1939
{
	struct socket *sock = s->sock, *nsock;
	int err;

	/* Fast check for a new connection.
	 * Avoids unnesesary socket allocations. */
	if (list_empty(&bt_sk(sock->sk)->accept_q))
		return;

	BT_DBG("session %p", s);

1940 1941
	err = kernel_accept(sock, &nsock, O_NONBLOCK);
	if (err < 0)
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		return;

	/* Set our callbacks */
	nsock->sk->sk_data_ready   = rfcomm_l2data_ready;
	nsock->sk->sk_state_change = rfcomm_l2state_change;

	s = rfcomm_session_add(nsock, BT_OPEN);
	if (s) {
1950 1951
		/* We should adjust MTU on incoming sessions.
		 * L2CAP MTU minus UIH header and FCS. */
1952 1953
		s->mtu = min(l2cap_pi(nsock->sk)->chan->omtu,
				l2cap_pi(nsock->sk)->chan->imtu) - 5;
1954

1955
		rfcomm_schedule();
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	} else
		sock_release(nsock);
}

1960
static struct rfcomm_session *rfcomm_check_connection(struct rfcomm_session *s)
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{
	struct sock *sk = s->sock->sk;

	BT_DBG("%p state %ld", s, s->state);

1966
	switch (sk->sk_state) {
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	case BT_CONNECTED:
		s->state = BT_CONNECT;

		/* We can adjust MTU on outgoing sessions.
		 * L2CAP MTU minus UIH header and FCS. */
1972
		s->mtu = min(l2cap_pi(sk)->chan->omtu, l2cap_pi(sk)->chan->imtu) - 5;
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1973 1974 1975 1976 1977

		rfcomm_send_sabm(s, 0);
		break;

	case BT_CLOSED:
1978
		s = rfcomm_session_close(s, sk->sk_err);
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		break;
	}
1981
	return s;
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}

1984
static void rfcomm_process_sessions(void)
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{
	struct list_head *p, *n;

	rfcomm_lock();

	list_for_each_safe(p, n, &session_list) {
		struct rfcomm_session *s;
		s = list_entry(p, struct rfcomm_session, list);

1994 1995 1996 1997 1998 1999
		if (test_and_clear_bit(RFCOMM_TIMED_OUT, &s->flags)) {
			s->state = BT_DISCONN;
			rfcomm_send_disc(s, 0);
			continue;
		}

2000 2001
		switch (s->state) {
		case BT_LISTEN:
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			rfcomm_accept_connection(s);
			continue;

		case BT_BOUND:
2006
			s = rfcomm_check_connection(s);
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			break;

		default:
2010
			s = rfcomm_process_rx(s);
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			break;
		}

2014 2015
		if (s)
			rfcomm_process_dlcs(s);
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2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030
	}

	rfcomm_unlock();
}

static int rfcomm_add_listener(bdaddr_t *ba)
{
	struct sockaddr_l2 addr;
	struct socket *sock;
	struct sock *sk;
	struct rfcomm_session *s;
	int    err = 0;

	/* Create socket */
	err = rfcomm_l2sock_create(&sock);
2031
	if (err < 0) {
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		BT_ERR("Create socket failed %d", err);
		return err;
	}

	/* Bind socket */
	bacpy(&addr.l2_bdaddr, ba);
	addr.l2_family = AF_BLUETOOTH;
2039
	addr.l2_psm    = cpu_to_le16(RFCOMM_PSM);
2040
	addr.l2_cid    = 0;
2041
	addr.l2_bdaddr_type = BDADDR_BREDR;
2042
	err = kernel_bind(sock, (struct sockaddr *) &addr, sizeof(addr));
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	if (err < 0) {
		BT_ERR("Bind failed %d", err);
		goto failed;
	}

	/* Set L2CAP options */
	sk = sock->sk;
	lock_sock(sk);
2051
	l2cap_pi(sk)->chan->imtu = l2cap_mtu;
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	release_sock(sk);

	/* Start listening on the socket */
2055
	err = kernel_listen(sock, 10);
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	if (err) {
		BT_ERR("Listen failed %d", err);
		goto failed;
	}

	/* Add listening session */
	s = rfcomm_session_add(sock, BT_LISTEN);
2063 2064
	if (!s) {
		err = -ENOMEM;
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		goto failed;
2066
	}
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2067 2068 2069 2070 2071 2072 2073 2074 2075 2076 2077 2078 2079 2080 2081 2082 2083 2084 2085 2086 2087 2088

	return 0;
failed:
	sock_release(sock);
	return err;
}

static void rfcomm_kill_listener(void)
{
	struct rfcomm_session *s;
	struct list_head *p, *n;

	BT_DBG("");

	list_for_each_safe(p, n, &session_list) {
		s = list_entry(p, struct rfcomm_session, list);
		rfcomm_session_del(s);
	}
}

static int rfcomm_run(void *unused)
{
2089
	BT_DBG("");
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2090 2091 2092 2093 2094

	set_user_nice(current, -10);

	rfcomm_add_listener(BDADDR_ANY);

2095
	while (1) {
2096
		set_current_state(TASK_INTERRUPTIBLE);
2097 2098 2099

		if (kthread_should_stop())
			break;
2100 2101 2102

		/* Process stuff */
		rfcomm_process_sessions();
2103 2104

		schedule();
2105
	}
2106
	__set_current_state(TASK_RUNNING);
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2107 2108 2109 2110 2111 2112

	rfcomm_kill_listener();

	return 0;
}

2113
static void rfcomm_security_cfm(struct hci_conn *conn, u8 status, u8 encrypt)
L
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2114 2115 2116 2117 2118 2119 2120 2121 2122 2123 2124 2125 2126 2127
{
	struct rfcomm_session *s;
	struct rfcomm_dlc *d;
	struct list_head *p, *n;

	BT_DBG("conn %p status 0x%02x encrypt 0x%02x", conn, status, encrypt);

	s = rfcomm_session_get(&conn->hdev->bdaddr, &conn->dst);
	if (!s)
		return;

	list_for_each_safe(p, n, &s->dlcs) {
		d = list_entry(p, struct rfcomm_dlc, list);

2128 2129 2130
		if (test_and_clear_bit(RFCOMM_SEC_PENDING, &d->flags)) {
			rfcomm_dlc_clear_timer(d);
			if (status || encrypt == 0x00) {
2131
				set_bit(RFCOMM_ENC_DROP, &d->flags);
2132 2133 2134 2135 2136 2137 2138 2139 2140
				continue;
			}
		}

		if (d->state == BT_CONNECTED && !status && encrypt == 0x00) {
			if (d->sec_level == BT_SECURITY_MEDIUM) {
				set_bit(RFCOMM_SEC_PENDING, &d->flags);
				rfcomm_dlc_set_timer(d, RFCOMM_AUTH_TIMEOUT);
				continue;
2141 2142
			} else if (d->sec_level == BT_SECURITY_HIGH ||
				   d->sec_level == BT_SECURITY_FIPS) {
2143
				set_bit(RFCOMM_ENC_DROP, &d->flags);
2144 2145
				continue;
			}
2146 2147
		}

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		if (!test_and_clear_bit(RFCOMM_AUTH_PENDING, &d->flags))
			continue;

2151
		if (!status && hci_conn_check_secure(conn, d->sec_level))
L
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2152 2153 2154 2155 2156
			set_bit(RFCOMM_AUTH_ACCEPT, &d->flags);
		else
			set_bit(RFCOMM_AUTH_REJECT, &d->flags);
	}

2157
	rfcomm_schedule();
L
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2158 2159 2160 2161
}

static struct hci_cb rfcomm_cb = {
	.name		= "RFCOMM",
2162
	.security_cfm	= rfcomm_security_cfm
L
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2163 2164
};

2165
static int rfcomm_dlc_debugfs_show(struct seq_file *f, void *x)
L
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2166 2167 2168 2169 2170
{
	struct rfcomm_session *s;

	rfcomm_lock();

2171
	list_for_each_entry(s, &session_list, list) {
2172
		struct l2cap_chan *chan = l2cap_pi(s->sock->sk)->chan;
2173 2174
		struct rfcomm_dlc *d;
		list_for_each_entry(d, &s->dlcs, list) {
2175
			seq_printf(f, "%pMR %pMR %ld %d %d %d %d\n",
2176
				   &chan->src, &chan->dst,
2177 2178
				   d->state, d->dlci, d->mtu,
				   d->rx_credits, d->tx_credits);
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2179 2180 2181 2182 2183
		}
	}

	rfcomm_unlock();

2184 2185 2186 2187 2188 2189
	return 0;
}

static int rfcomm_dlc_debugfs_open(struct inode *inode, struct file *file)
{
	return single_open(file, rfcomm_dlc_debugfs_show, inode->i_private);
L
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}

2192 2193 2194 2195 2196 2197 2198 2199
static const struct file_operations rfcomm_dlc_debugfs_fops = {
	.open		= rfcomm_dlc_debugfs_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
	.release	= single_release,
};

static struct dentry *rfcomm_dlc_debugfs;
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/* ---- Initialization ---- */
static int __init rfcomm_init(void)
{
2204
	int err;
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	hci_register_cb(&rfcomm_cb);

2208 2209
	rfcomm_thread = kthread_run(rfcomm_run, NULL, "krfcommd");
	if (IS_ERR(rfcomm_thread)) {
2210 2211
		err = PTR_ERR(rfcomm_thread);
		goto unregister;
2212
	}
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2214 2215 2216
	err = rfcomm_init_ttys();
	if (err < 0)
		goto stop;
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2218 2219 2220
	err = rfcomm_init_sockets();
	if (err < 0)
		goto cleanup;
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2222 2223
	BT_INFO("RFCOMM ver %s", VERSION);

2224 2225 2226 2227 2228 2229 2230
	if (IS_ERR_OR_NULL(bt_debugfs))
		return 0;

	rfcomm_dlc_debugfs = debugfs_create_file("rfcomm_dlc", 0444,
						 bt_debugfs, NULL,
						 &rfcomm_dlc_debugfs_fops);

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	return 0;
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2232

2233
cleanup:
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	rfcomm_cleanup_ttys();
2235 2236

stop:
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	kthread_stop(rfcomm_thread);
2238 2239

unregister:
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	hci_unregister_cb(&rfcomm_cb);

2242
	return err;
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}

static void __exit rfcomm_exit(void)
{
2247
	debugfs_remove(rfcomm_dlc_debugfs);
2248

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	hci_unregister_cb(&rfcomm_cb);

2251
	kthread_stop(rfcomm_thread);
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	rfcomm_cleanup_ttys();

	rfcomm_cleanup_sockets();
}

module_init(rfcomm_init);
module_exit(rfcomm_exit);

2261 2262 2263
module_param(disable_cfc, bool, 0644);
MODULE_PARM_DESC(disable_cfc, "Disable credit based flow control");

2264 2265 2266
module_param(channel_mtu, int, 0644);
MODULE_PARM_DESC(channel_mtu, "Default MTU for the RFCOMM channel");

2267 2268 2269
module_param(l2cap_mtu, uint, 0644);
MODULE_PARM_DESC(l2cap_mtu, "Default MTU for the L2CAP connection");

2270 2271 2272
module_param(l2cap_ertm, bool, 0644);
MODULE_PARM_DESC(l2cap_ertm, "Use L2CAP ERTM mode for connection");

2273
MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>");
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MODULE_DESCRIPTION("Bluetooth RFCOMM ver " VERSION);
MODULE_VERSION(VERSION);
MODULE_LICENSE("GPL");
MODULE_ALIAS("bt-proto-3");