linux-hardened/net/bluetooth/hidp/core.c

/* 
   HIDP implementation for Linux Bluetooth stack (BlueZ).
   Copyright (C) 2003-2004 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
   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 
   OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

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

#include <linux/module.h>

#include <linux/types.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/poll.h>
#include <linux/fcntl.h>
#include <linux/skbuff.h>
#include <linux/socket.h>
#include <linux/ioctl.h>
#include <linux/file.h>
#include <linux/init.h>
#include <linux/wait.h>
#include <net/sock.h>

#include <linux/input.h>

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

#include "hidp.h"

#ifndef CONFIG_BT_HIDP_DEBUG
#undef  BT_DBG
#define BT_DBG(D...)
#endif

#define VERSION "1.1"

static DECLARE_RWSEM(hidp_session_sem);
static LIST_HEAD(hidp_session_list);

static unsigned char hidp_keycode[256] = {
	  0,  0,  0,  0, 30, 48, 46, 32, 18, 33, 34, 35, 23, 36, 37, 38,
	 50, 49, 24, 25, 16, 19, 31, 20, 22, 47, 17, 45, 21, 44,  2,  3,
	  4,  5,  6,  7,  8,  9, 10, 11, 28,  1, 14, 15, 57, 12, 13, 26,
	 27, 43, 43, 39, 40, 41, 51, 52, 53, 58, 59, 60, 61, 62, 63, 64,
	 65, 66, 67, 68, 87, 88, 99, 70,119,110,102,104,111,107,109,106,
	105,108,103, 69, 98, 55, 74, 78, 96, 79, 80, 81, 75, 76, 77, 71,
	 72, 73, 82, 83, 86,127,116,117,183,184,185,186,187,188,189,190,
	191,192,193,194,134,138,130,132,128,129,131,137,133,135,136,113,
	115,114,  0,  0,  0,121,  0, 89, 93,124, 92, 94, 95,  0,  0,  0,
	122,123, 90, 91, 85,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,
	  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,
	  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,
	  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,
	  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,
	 29, 42, 56,125, 97, 54,100,126,164,166,165,163,161,115,114,113,
	150,158,159,128,136,177,178,176,142,152,173,140
};

static unsigned char hidp_mkeyspat[] = { 0x01, 0x01, 0x01, 0x01, 0x01, 0x01 };

static struct hidp_session *__hidp_get_session(bdaddr_t *bdaddr)
{
	struct hidp_session *session;
	struct list_head *p;

	BT_DBG("");

	list_for_each(p, &hidp_session_list) {
		session = list_entry(p, struct hidp_session, list);
		if (!bacmp(bdaddr, &session->bdaddr))
			return session;
	}
	return NULL;
}

static void __hidp_link_session(struct hidp_session *session)
{
	__module_get(THIS_MODULE);
	list_add(&session->list, &hidp_session_list);
}

static void __hidp_unlink_session(struct hidp_session *session)
{
	list_del(&session->list);
	module_put(THIS_MODULE);
}

static void __hidp_copy_session(struct hidp_session *session, struct hidp_conninfo *ci)
{
	bacpy(&ci->bdaddr, &session->bdaddr);

	ci->flags = session->flags;
	ci->state = session->state;

	ci->vendor  = 0x0000;
	ci->product = 0x0000;
	ci->version = 0x0000;
	memset(ci->name, 0, 128);

	if (session->input) {
		ci->vendor  = session->input->id.vendor;
		ci->product = session->input->id.product;
		ci->version = session->input->id.version;
		if (session->input->name)
			strncpy(ci->name, session->input->name, 128);
		else
			strncpy(ci->name, "HID Boot Device", 128);
	}
}

static int hidp_input_event(struct input_dev *dev, unsigned int type, unsigned int code, int value)
{
	struct hidp_session *session = dev->private;
	struct sk_buff *skb;
	unsigned char newleds;

	BT_DBG("input %p type %d code %d value %d", dev, type, code, value);

	if (type != EV_LED)
		return -1;

	newleds = (!!test_bit(LED_KANA,    dev->led) << 3) |
		  (!!test_bit(LED_COMPOSE, dev->led) << 3) |
		  (!!test_bit(LED_SCROLLL, dev->led) << 2) |
		  (!!test_bit(LED_CAPSL,   dev->led) << 1) |
		  (!!test_bit(LED_NUML,    dev->led));

	if (session->leds == newleds)
		return 0;

	session->leds = newleds;

	if (!(skb = alloc_skb(3, GFP_ATOMIC))) {
		BT_ERR("Can't allocate memory for new frame");
		return -ENOMEM;
	}

	*skb_put(skb, 1) = HIDP_TRANS_DATA | HIDP_DATA_RTYPE_OUPUT;
	*skb_put(skb, 1) = 0x01;
	*skb_put(skb, 1) = newleds;

	skb_queue_tail(&session->intr_transmit, skb);

	hidp_schedule(session);

	return 0;
}

static void hidp_input_report(struct hidp_session *session, struct sk_buff *skb)
{
	struct input_dev *dev = session->input;
	unsigned char *keys = session->keys;
	unsigned char *udata = skb->data + 1;
	signed char *sdata = skb->data + 1;
	int i, size = skb->len - 1;

	switch (skb->data[0]) {
	case 0x01:	/* Keyboard report */
		for (i = 0; i < 8; i++)
			input_report_key(dev, hidp_keycode[i + 224], (udata[0] >> i) & 1);

		/* If all the key codes have been set to 0x01, it means
		 * too many keys were pressed at the same time. */
		if (!memcmp(udata + 2, hidp_mkeyspat, 6))
			break;

		for (i = 2; i < 8; i++) {
			if (keys[i] > 3 && memscan(udata + 2, keys[i], 6) == udata + 8) {
				if (hidp_keycode[keys[i]])
					input_report_key(dev, hidp_keycode[keys[i]], 0);
				else
					BT_ERR("Unknown key (scancode %#x) released.", keys[i]);
			}

			if (udata[i] > 3 && memscan(keys + 2, udata[i], 6) == keys + 8) {
				if (hidp_keycode[udata[i]])
					input_report_key(dev, hidp_keycode[udata[i]], 1);
				else
					BT_ERR("Unknown key (scancode %#x) pressed.", udata[i]);
			}
		}

		memcpy(keys, udata, 8);
		break;

	case 0x02:	/* Mouse report */
		input_report_key(dev, BTN_LEFT,   sdata[0] & 0x01);
		input_report_key(dev, BTN_RIGHT,  sdata[0] & 0x02);
		input_report_key(dev, BTN_MIDDLE, sdata[0] & 0x04);
		input_report_key(dev, BTN_SIDE,   sdata[0] & 0x08);
		input_report_key(dev, BTN_EXTRA,  sdata[0] & 0x10);

		input_report_rel(dev, REL_X, sdata[1]);
		input_report_rel(dev, REL_Y, sdata[2]);

		if (size > 3)
			input_report_rel(dev, REL_WHEEL, sdata[3]);
		break;
	}

	input_sync(dev);
}

static void hidp_idle_timeout(unsigned long arg)
{
	struct hidp_session *session = (struct hidp_session *) arg;

	atomic_inc(&session->terminate);
	hidp_schedule(session);
}

static inline void hidp_set_timer(struct hidp_session *session)
{
	if (session->idle_to > 0)
		mod_timer(&session->timer, jiffies + HZ * session->idle_to);
}

static inline void hidp_del_timer(struct hidp_session *session)
{
	if (session->idle_to > 0)
		del_timer(&session->timer);
}

static int __hidp_send_ctrl_message(struct hidp_session *session,
			unsigned char hdr, unsigned char *data, int size)
{
	struct sk_buff *skb;

	BT_DBG("session %p data %p size %d", session, data, size);

	if (!(skb = alloc_skb(size + 1, GFP_ATOMIC))) {
		BT_ERR("Can't allocate memory for new frame");
		return -ENOMEM;
	}

	*skb_put(skb, 1) = hdr;
	if (data && size > 0)
		memcpy(skb_put(skb, size), data, size);

	skb_queue_tail(&session->ctrl_transmit, skb);

	return 0;
}

static int inline hidp_send_ctrl_message(struct hidp_session *session,
			unsigned char hdr, unsigned char *data, int size)
{
	int err;

	err = __hidp_send_ctrl_message(session, hdr, data, size);

	hidp_schedule(session);

	return err;
}

static inline void hidp_process_handshake(struct hidp_session *session, unsigned char param)
{
	BT_DBG("session %p param 0x%02x", session, param);

	switch (param) {
	case HIDP_HSHK_SUCCESSFUL:
		/* FIXME: Call into SET_ GET_ handlers here */
		break;

	case HIDP_HSHK_NOT_READY:
	case HIDP_HSHK_ERR_INVALID_REPORT_ID:
	case HIDP_HSHK_ERR_UNSUPPORTED_REQUEST:
	case HIDP_HSHK_ERR_INVALID_PARAMETER:
		/* FIXME: Call into SET_ GET_ handlers here */
		break;

	case HIDP_HSHK_ERR_UNKNOWN:
		break;

	case HIDP_HSHK_ERR_FATAL:
		/* Device requests a reboot, as this is the only way this error
 		 * can be recovered. */
		__hidp_send_ctrl_message(session,
			HIDP_TRANS_HID_CONTROL | HIDP_CTRL_SOFT_RESET, NULL, 0);
		break;

	default:
		__hidp_send_ctrl_message(session,
			HIDP_TRANS_HANDSHAKE | HIDP_HSHK_ERR_INVALID_PARAMETER, NULL, 0);
		break;
	}
}

static inline void hidp_process_hid_control(struct hidp_session *session, unsigned char param)
{
	BT_DBG("session %p param 0x%02x", session, param);

	switch (param) {
	case HIDP_CTRL_NOP:
		break;

	case HIDP_CTRL_VIRTUAL_CABLE_UNPLUG:
		/* Flush the transmit queues */
		skb_queue_purge(&session->ctrl_transmit);
		skb_queue_purge(&session->intr_transmit);

		/* Kill session thread */
		atomic_inc(&session->terminate);
		break;

	case HIDP_CTRL_HARD_RESET:
	case HIDP_CTRL_SOFT_RESET:
	case HIDP_CTRL_SUSPEND:
	case HIDP_CTRL_EXIT_SUSPEND:
		/* FIXME: We have to parse these and return no error */
		break;

	default:
		__hidp_send_ctrl_message(session,
			HIDP_TRANS_HANDSHAKE | HIDP_HSHK_ERR_INVALID_PARAMETER, NULL, 0);
		break;
	}
}

static inline void hidp_process_data(struct hidp_session *session, struct sk_buff *skb, unsigned char param)
{
	BT_DBG("session %p skb %p len %d param 0x%02x", session, skb, skb->len, param);

	switch (param) {
	case HIDP_DATA_RTYPE_INPUT:
		hidp_set_timer(session);

		if (session->input)
			hidp_input_report(session, skb);
		break;

	case HIDP_DATA_RTYPE_OTHER:
	case HIDP_DATA_RTYPE_OUPUT:
	case HIDP_DATA_RTYPE_FEATURE:
		break;

	default:
		__hidp_send_ctrl_message(session,
			HIDP_TRANS_HANDSHAKE | HIDP_HSHK_ERR_INVALID_PARAMETER, NULL, 0);
	}
}

static inline void hidp_recv_ctrl_frame(struct hidp_session *session, struct sk_buff *skb)
{
	unsigned char hdr, type, param;

	BT_DBG("session %p skb %p len %d", session, skb, skb->len);

	hdr = skb->data[0];
	skb_pull(skb, 1);

	type = hdr & HIDP_HEADER_TRANS_MASK;
	param = hdr & HIDP_HEADER_PARAM_MASK;

	switch (type) {
	case HIDP_TRANS_HANDSHAKE:
		hidp_process_handshake(session, param);
		break;

	case HIDP_TRANS_HID_CONTROL:
		hidp_process_hid_control(session, param);
		break;

	case HIDP_TRANS_DATA:
		hidp_process_data(session, skb, param);
		break;

	default:
		__hidp_send_ctrl_message(session,
			HIDP_TRANS_HANDSHAKE | HIDP_HSHK_ERR_UNSUPPORTED_REQUEST, NULL, 0);
		break;
	}

	kfree_skb(skb);
}

static inline void hidp_recv_intr_frame(struct hidp_session *session, struct sk_buff *skb)
{
	unsigned char hdr;

	BT_DBG("session %p skb %p len %d", session, skb, skb->len);

	hdr = skb->data[0];
	skb_pull(skb, 1);

	if (hdr == (HIDP_TRANS_DATA | HIDP_DATA_RTYPE_INPUT)) {
		hidp_set_timer(session);
		if (session->input)
			hidp_input_report(session, skb);
	} else {
		BT_DBG("Unsupported protocol header 0x%02x", hdr);
	}

	kfree_skb(skb);
}

static int hidp_send_frame(struct socket *sock, unsigned char *data, int len)
{
	struct kvec iv = { data, len };
	struct msghdr msg;

	BT_DBG("sock %p data %p len %d", sock, data, len);

	if (!len)
		return 0;

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

	return kernel_sendmsg(sock, &msg, &iv, 1, len);
}

static void hidp_process_transmit(struct hidp_session *session)
{
	struct sk_buff *skb;

	BT_DBG("session %p", session);

	while ((skb = skb_dequeue(&session->ctrl_transmit))) {
		if (hidp_send_frame(session->ctrl_sock, skb->data, skb->len) < 0) {
			skb_queue_head(&session->ctrl_transmit, skb);
			break;
		}

		hidp_set_timer(session);
		kfree_skb(skb);
	}

	while ((skb = skb_dequeue(&session->intr_transmit))) {
		if (hidp_send_frame(session->intr_sock, skb->data, skb->len) < 0) {
			skb_queue_head(&session->intr_transmit, skb);
			break;
		}

		hidp_set_timer(session);
		kfree_skb(skb);
	}
}

static int hidp_session(void *arg)
{
	struct hidp_session *session = arg;
	struct sock *ctrl_sk = session->ctrl_sock->sk;
	struct sock *intr_sk = session->intr_sock->sk;
	struct sk_buff *skb;
	int vendor = 0x0000, product = 0x0000;
	wait_queue_t ctrl_wait, intr_wait;

	BT_DBG("session %p", session);

	if (session->input) {
		vendor  = session->input->id.vendor;
		product = session->input->id.product;
	}

	daemonize("khidpd_%04x%04x", vendor, product);
	set_user_nice(current, -15);
	current->flags |= PF_NOFREEZE;

	init_waitqueue_entry(&ctrl_wait, current);
	init_waitqueue_entry(&intr_wait, current);
	add_wait_queue(ctrl_sk->sk_sleep, &ctrl_wait);
	add_wait_queue(intr_sk->sk_sleep, &intr_wait);
	while (!atomic_read(&session->terminate)) {
		set_current_state(TASK_INTERRUPTIBLE);

		if (ctrl_sk->sk_state != BT_CONNECTED || intr_sk->sk_state != BT_CONNECTED)
			break;

		while ((skb = skb_dequeue(&ctrl_sk->sk_receive_queue))) {
			skb_orphan(skb);
			hidp_recv_ctrl_frame(session, skb);
		}

		while ((skb = skb_dequeue(&intr_sk->sk_receive_queue))) {
			skb_orphan(skb);
			hidp_recv_intr_frame(session, skb);
		}

		hidp_process_transmit(session);

		schedule();
	}
	set_current_state(TASK_RUNNING);
	remove_wait_queue(intr_sk->sk_sleep, &intr_wait);
	remove_wait_queue(ctrl_sk->sk_sleep, &ctrl_wait);

	down_write(&hidp_session_sem);

	hidp_del_timer(session);

	if (intr_sk->sk_state != BT_CONNECTED)
		wait_event_timeout(*(ctrl_sk->sk_sleep), (ctrl_sk->sk_state == BT_CLOSED), HZ);

	fput(session->intr_sock->file);

	wait_event_timeout(*(intr_sk->sk_sleep), (intr_sk->sk_state == BT_CLOSED), HZ);

	fput(session->ctrl_sock->file);

	__hidp_unlink_session(session);

	if (session->input) {
		input_unregister_device(session->input);
		session->input = NULL;
	}

	up_write(&hidp_session_sem);

	kfree(session);
	return 0;
}

static struct device *hidp_get_device(struct hidp_session *session)
{
	bdaddr_t *src = &bt_sk(session->ctrl_sock->sk)->src;
	bdaddr_t *dst = &bt_sk(session->ctrl_sock->sk)->dst;
	struct hci_dev *hdev;
	struct hci_conn *conn;

	hdev = hci_get_route(dst, src);
	if (!hdev)
		return NULL;

	conn = hci_conn_hash_lookup_ba(hdev, ACL_LINK, dst);
	if (!conn)
		return NULL;

	hci_dev_put(hdev);

	return &conn->dev;
}

static inline void hidp_setup_input(struct hidp_session *session, struct hidp_connadd_req *req)
{
	struct input_dev *input = session->input;
	int i;

	input->private = session;

	input->name = "Bluetooth HID Boot Protocol Device";

	input->id.bustype = BUS_BLUETOOTH;
	input->id.vendor  = req->vendor;
	input->id.product = req->product;
	input->id.version = req->version;

	if (req->subclass & 0x40) {
		set_bit(EV_KEY, input->evbit);
		set_bit(EV_LED, input->evbit);
		set_bit(EV_REP, input->evbit);

		set_bit(LED_NUML,    input->ledbit);
		set_bit(LED_CAPSL,   input->ledbit);
		set_bit(LED_SCROLLL, input->ledbit);
		set_bit(LED_COMPOSE, input->ledbit);
		set_bit(LED_KANA,    input->ledbit);

		for (i = 0; i < sizeof(hidp_keycode); i++)
			set_bit(hidp_keycode[i], input->keybit);
		clear_bit(0, input->keybit);
	}

	if (req->subclass & 0x80) {
		input->evbit[0] = BIT(EV_KEY) | BIT(EV_REL);
		input->keybit[LONG(BTN_MOUSE)] = BIT(BTN_LEFT) | BIT(BTN_RIGHT) | BIT(BTN_MIDDLE);
		input->relbit[0] = BIT(REL_X) | BIT(REL_Y);
		input->keybit[LONG(BTN_MOUSE)] |= BIT(BTN_SIDE) | BIT(BTN_EXTRA);
		input->relbit[0] |= BIT(REL_WHEEL);
	}

	input->cdev.dev = hidp_get_device(session);

	input->event = hidp_input_event;

	input_register_device(input);
}

int hidp_add_connection(struct hidp_connadd_req *req, struct socket *ctrl_sock, struct socket *intr_sock)
{
	struct hidp_session *session, *s;
	int err;

	BT_DBG("");

	if (bacmp(&bt_sk(ctrl_sock->sk)->src, &bt_sk(intr_sock->sk)->src) ||
			bacmp(&bt_sk(ctrl_sock->sk)->dst, &bt_sk(intr_sock->sk)->dst))
		return -ENOTUNIQ;

	session = kzalloc(sizeof(struct hidp_session), GFP_KERNEL);
	if (!session)
		return -ENOMEM;

	session->input = input_allocate_device();
	if (!session->input) {
		kfree(session);
		return -ENOMEM;
	}

	down_write(&hidp_session_sem);

	s = __hidp_get_session(&bt_sk(ctrl_sock->sk)->dst);
	if (s && s->state == BT_CONNECTED) {
		err = -EEXIST;
		goto failed;
	}

	bacpy(&session->bdaddr, &bt_sk(ctrl_sock->sk)->dst);

	session->ctrl_mtu = min_t(uint, l2cap_pi(ctrl_sock->sk)->omtu, l2cap_pi(ctrl_sock->sk)->imtu);
	session->intr_mtu = min_t(uint, l2cap_pi(intr_sock->sk)->omtu, l2cap_pi(intr_sock->sk)->imtu);

	BT_DBG("ctrl mtu %d intr mtu %d", session->ctrl_mtu, session->intr_mtu);

	session->ctrl_sock = ctrl_sock;
	session->intr_sock = intr_sock;
	session->state     = BT_CONNECTED;

	init_timer(&session->timer);

	session->timer.function = hidp_idle_timeout;
	session->timer.data     = (unsigned long) session;

	skb_queue_head_init(&session->ctrl_transmit);
	skb_queue_head_init(&session->intr_transmit);

	session->flags   = req->flags & (1 << HIDP_BLUETOOTH_VENDOR_ID);
	session->idle_to = req->idle_to;

	if (session->input)
		hidp_setup_input(session, req);

	__hidp_link_session(session);

	hidp_set_timer(session);

	err = kernel_thread(hidp_session, session, CLONE_KERNEL);
	if (err < 0)
		goto unlink;

	if (session->input) {
		hidp_send_ctrl_message(session,
			HIDP_TRANS_SET_PROTOCOL | HIDP_PROTO_BOOT, NULL, 0);
		session->flags |= (1 << HIDP_BOOT_PROTOCOL_MODE);

		session->leds = 0xff;
		hidp_input_event(session->input, EV_LED, 0, 0);
	}

	up_write(&hidp_session_sem);
	return 0;

unlink:
	hidp_del_timer(session);

	__hidp_unlink_session(session);

	if (session->input) {
		input_unregister_device(session->input);
		session->input = NULL; /* don't try to free it here */
	}

failed:
	up_write(&hidp_session_sem);

	kfree(session->input);
	kfree(session);
	return err;
}

int hidp_del_connection(struct hidp_conndel_req *req)
{
	struct hidp_session *session;
	int err = 0;

	BT_DBG("");

	down_read(&hidp_session_sem);

	session = __hidp_get_session(&req->bdaddr);
	if (session) {
		if (req->flags & (1 << HIDP_VIRTUAL_CABLE_UNPLUG)) {
			hidp_send_ctrl_message(session,
				HIDP_TRANS_HID_CONTROL | HIDP_CTRL_VIRTUAL_CABLE_UNPLUG, NULL, 0);
		} else {
			/* Flush the transmit queues */
			skb_queue_purge(&session->ctrl_transmit);
			skb_queue_purge(&session->intr_transmit);

			/* Kill session thread */
			atomic_inc(&session->terminate);
			hidp_schedule(session);
		}
	} else
		err = -ENOENT;

	up_read(&hidp_session_sem);
	return err;
}

int hidp_get_connlist(struct hidp_connlist_req *req)
{
	struct list_head *p;
	int err = 0, n = 0;

	BT_DBG("");

	down_read(&hidp_session_sem);

	list_for_each(p, &hidp_session_list) {
		struct hidp_session *session;
		struct hidp_conninfo ci;

		session = list_entry(p, struct hidp_session, list);

		__hidp_copy_session(session, &ci);

		if (copy_to_user(req->ci, &ci, sizeof(ci))) {
			err = -EFAULT;
			break;
		}

		if (++n >= req->cnum)
			break;

		req->ci++;
	}
	req->cnum = n;

	up_read(&hidp_session_sem);
	return err;
}

int hidp_get_conninfo(struct hidp_conninfo *ci)
{
	struct hidp_session *session;
	int err = 0;

	down_read(&hidp_session_sem);

	session = __hidp_get_session(&ci->bdaddr);
	if (session)
		__hidp_copy_session(session, ci);
	else
		err = -ENOENT;

	up_read(&hidp_session_sem);
	return err;
}

static int __init hidp_init(void)
{
	l2cap_load();

	BT_INFO("HIDP (Human Interface Emulation) ver %s", VERSION);

	return hidp_init_sockets();
}

static void __exit hidp_exit(void)
{
	hidp_cleanup_sockets();
}

module_init(hidp_init);
module_exit(hidp_exit);

MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>");
MODULE_DESCRIPTION("Bluetooth HIDP ver " VERSION);
MODULE_VERSION(VERSION);
MODULE_LICENSE("GPL");
MODULE_ALIAS("bt-proto-6");