/*
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
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.
*/
/*
* RFCOMM TTY.
*/
#include <linux/module.h>
#include <linux/tty.h>
#include <linux/tty_driver.h>
#include <linux/tty_flip.h>
#include <net/bluetooth/bluetooth.h>
#include <net/bluetooth/hci_core.h>
#include <net/bluetooth/rfcomm.h>
#define RFCOMM_TTY_MAGIC 0x6d02 /* magic number for rfcomm struct */
#define RFCOMM_TTY_PORTS RFCOMM_MAX_DEV /* whole lotta rfcomm devices */
#define RFCOMM_TTY_MAJOR 216 /* device node major id of the usb/bluetooth.c driver */
#define RFCOMM_TTY_MINOR 0
static DEFINE_MUTEX(rfcomm_ioctl_mutex);
static struct tty_driver *rfcomm_tty_driver;
struct rfcomm_dev {
struct tty_port port;
struct list_head list;
char name[12];
int id;
unsigned long flags;
int err;
unsigned long status; /* don't export to userspace */
bdaddr_t src;
bdaddr_t dst;
u8 channel;
uint modem_status;
struct rfcomm_dlc *dlc;
struct device *tty_dev;
atomic_t wmem_alloc;
struct sk_buff_head pending;
};
static LIST_HEAD(rfcomm_dev_list);
static DEFINE_MUTEX(rfcomm_dev_lock);
static void rfcomm_dev_data_ready(struct rfcomm_dlc *dlc, struct sk_buff *skb);
static void rfcomm_dev_state_change(struct rfcomm_dlc *dlc, int err);
static void rfcomm_dev_modem_status(struct rfcomm_dlc *dlc, u8 v24_sig);
/* ---- Device functions ---- */
static void rfcomm_dev_destruct(struct tty_port *port)
{
struct rfcomm_dev *dev = container_of(port, struct rfcomm_dev, port);
struct rfcomm_dlc *dlc = dev->dlc;
BT_DBG("dev %p dlc %p", dev, dlc);
rfcomm_dlc_lock(dlc);
/* Detach DLC if it's owned by this dev */
if (dlc->owner == dev)
dlc->owner = NULL;
rfcomm_dlc_unlock(dlc);
rfcomm_dlc_put(dlc);
if (dev->tty_dev)
tty_unregister_device(rfcomm_tty_driver, dev->id);
mutex_lock(&rfcomm_dev_lock);
list_del(&dev->list);
mutex_unlock(&rfcomm_dev_lock);
kfree(dev);
/* It's safe to call module_put() here because socket still
holds reference to this module. */
module_put(THIS_MODULE);
}
/* device-specific initialization: open the dlc */
static int rfcomm_dev_activate(struct tty_port *port, struct tty_struct *tty)
{
struct rfcomm_dev *dev = container_of(port, struct rfcomm_dev, port);
int err;
err = rfcomm_dlc_open(dev->dlc, &dev->src, &dev->dst, dev->channel);
if (err)
set_bit(TTY_IO_ERROR, &tty->flags);
return err;
}
/* we block the open until the dlc->state becomes BT_CONNECTED */
static int rfcomm_dev_carrier_raised(struct tty_port *port)
{
struct rfcomm_dev *dev = container_of(port, struct rfcomm_dev, port);
return (dev->dlc->state == BT_CONNECTED);
}
/* device-specific cleanup: close the dlc */
static void rfcomm_dev_shutdown(struct tty_port *port)
{
struct rfcomm_dev *dev = container_of(port, struct rfcomm_dev, port);
if (dev->tty_dev->parent)
device_move(dev->tty_dev, NULL, DPM_ORDER_DEV_LAST);
/* close the dlc */
rfcomm_dlc_close(dev->dlc, 0);
}
static const struct tty_port_operations rfcomm_port_ops = {
.destruct = rfcomm_dev_destruct,
.activate = rfcomm_dev_activate,
.shutdown = rfcomm_dev_shutdown,
.carrier_raised = rfcomm_dev_carrier_raised,
};
static struct rfcomm_dev *__rfcomm_dev_lookup(int id)
{
struct rfcomm_dev *dev;
list_for_each_entry(dev, &rfcomm_dev_list, list)
if (dev->id == id)
return dev;
return NULL;
}
static struct rfcomm_dev *rfcomm_dev_get(int id)
{
struct rfcomm_dev *dev;
mutex_lock(&rfcomm_dev_lock);
dev = __rfcomm_dev_lookup(id);
if (dev && !tty_port_get(&dev->port))
dev = NULL;
mutex_unlock(&rfcomm_dev_lock);
return dev;
}
static void rfcomm_reparent_device(struct rfcomm_dev *dev)
{
struct hci_dev *hdev;
struct hci_conn *conn;
hdev = hci_get_route(&dev->dst, &dev->src);
if (!hdev)
return;
/* The lookup results are unsafe to access without the
* hci device lock (FIXME: why is this not documented?)
*/
hci_dev_lock(hdev);
conn = hci_conn_hash_lookup_ba(hdev, ACL_LINK, &dev->dst);
/* Just because the acl link is in the hash table is no
* guarantee the sysfs device has been added ...
*/
if (conn && device_is_registered(&conn->dev))
device_move(dev->tty_dev, &conn->dev, DPM_ORDER_DEV_AFTER_PARENT);
hci_dev_unlock(hdev);
hci_dev_put(hdev);
}
static ssize_t show_address(struct device *tty_dev, struct device_attribute *attr, char *buf)
{
struct rfcomm_dev *dev = dev_get_drvdata(tty_dev);
return sprintf(buf, "%pMR\n", &dev->dst);
}
static ssize_t show_channel(struct device *tty_dev, struct device_attribute *attr, char *buf)
{
struct rfcomm_dev *dev = dev_get_drvdata(tty_dev);
return sprintf(buf, "%d\n", dev->channel);
}
static DEVICE_ATTR(address, S_IRUGO, show_address, NULL);
static DEVICE_ATTR(channel, S_IRUGO, show_channel, NULL);
static struct rfcomm_dev *__rfcomm_dev_add(struct rfcomm_dev_req *req,
struct rfcomm_dlc *dlc)
{
struct rfcomm_dev *dev, *entry;
struct list_head *head = &rfcomm_dev_list;
int err = 0;
dev = kzalloc(sizeof(struct rfcomm_dev), GFP_KERNEL);
if (!dev)
return ERR_PTR(-ENOMEM);
mutex_lock(&rfcomm_dev_lock);
if (req->dev_id < 0) {
dev->id = 0;
list_for_each_entry(entry, &rfcomm_dev_list, list) {
if (entry->id != dev->id)
break;
dev->id++;
head = &entry->list;
}
} else {
dev->id = req->dev_id;
list_for_each_entry(entry, &rfcomm_dev_list, list) {
if (entry->id == dev->id) {
err = -EADDRINUSE;
goto out;
}
if (entry->id > dev->id - 1)
break;
head = &entry->list;
}
}
if ((dev->id < 0) || (dev->id > RFCOMM_MAX_DEV - 1)) {
err = -ENFILE;
goto out;
}
sprintf(dev->name, "rfcomm%d", dev->id);
list_add(&dev->list, head);
bacpy(&dev->src, &req->src);
bacpy(&dev->dst, &req->dst);
dev->channel = req->channel;
dev->flags = req->flags &
((1 << RFCOMM_RELEASE_ONHUP) | (1 << RFCOMM_REUSE_DLC));
tty_port_init(&dev->port);
dev->port.ops = &rfcomm_port_ops;
skb_queue_head_init(&dev->pending);
rfcomm_dlc_lock(dlc);
if (req->flags & (1 << RFCOMM_REUSE_DLC)) {
struct sock *sk = dlc->owner;
struct sk_buff *skb;
BUG_ON(!sk);
rfcomm_dlc_throttle(dlc);
while ((skb = skb_dequeue(&sk->sk_receive_queue))) {
skb_orphan(skb);
skb_queue_tail(&dev->pending, skb);
atomic_sub(skb->len, &sk->sk_rmem_alloc);
}
}
dlc->data_ready = rfcomm_dev_data_ready;
dlc->state_change = rfcomm_dev_state_change;
dlc->modem_status = rfcomm_dev_modem_status;
dlc->owner = dev;
dev->dlc = dlc;
rfcomm_dev_modem_status(dlc, dlc->remote_v24_sig);
rfcomm_dlc_unlock(dlc);
/* It's safe to call __module_get() here because socket already
holds reference to this module. */
__module_get(THIS_MODULE);
mutex_unlock(&rfcomm_dev_lock);
return dev;
out:
mutex_unlock(&rfcomm_dev_lock);
kfree(dev);
return ERR_PTR(err);
}
static int rfcomm_dev_add(struct rfcomm_dev_req *req, struct rfcomm_dlc *dlc)
{
struct rfcomm_dev *dev;
struct device *tty;
BT_DBG("id %d channel %d", req->de
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