wireless.c

Linux Kernel 2.6.9 for OMAP1710

{
	if (v == SEQ_START_TOKEN)
		seq_printf(seq, "Inter-| sta-|   Quality        |   Discarded "
				"packets               | Missed | WE\n"
				" face | tus | link level noise |  nwid  "
				"crypt   frag  retry   misc | beacon | %d\n",
			   WIRELESS_EXT);
	else
		wireless_seq_printf_stats(seq, v);
	return 0;
}

extern void *dev_seq_start(struct seq_file *seq, loff_t *pos);
extern void *dev_seq_next(struct seq_file *seq, void *v, loff_t *pos);
extern void dev_seq_stop(struct seq_file *seq, void *v);

static struct seq_operations wireless_seq_ops = {
	.start = dev_seq_start,
	.next  = dev_seq_next,
	.stop  = dev_seq_stop,
	.show  = wireless_seq_show,
};

static int wireless_seq_open(struct inode *inode, struct file *file)
{
	return seq_open(file, &wireless_seq_ops);
}

static struct file_operations wireless_seq_fops = {
	.owner	 = THIS_MODULE,
	.open    = wireless_seq_open,
	.read    = seq_read,
	.llseek  = seq_lseek,
	.release = seq_release,
};

int __init wireless_proc_init(void)
{
	if (!proc_net_fops_create("wireless", S_IRUGO, &wireless_seq_fops))
		return -ENOMEM;

	return 0;
}
#endif	/* CONFIG_PROC_FS */

/************************** IOCTL SUPPORT **************************/
/*
 * The original user space API to configure all those Wireless Extensions
 * is through IOCTLs.
 * In there, we check if we need to call the new driver API (iw_handler)
 * or just call the driver ioctl handler.
 */

/* ---------------------------------------------------------------- */
/*
 *	Allow programatic access to /proc/net/wireless even if /proc
 *	doesn't exist... Also more efficient...
 */
static inline int dev_iwstats(struct net_device *dev, struct ifreq *ifr)
{
	/* Get stats from the driver */
	struct iw_statistics *stats;

	stats = get_wireless_stats(dev);
	if (stats != (struct iw_statistics *) NULL) {
		struct iwreq *	wrq = (struct iwreq *)ifr;

		/* Copy statistics to the user buffer */
		if(copy_to_user(wrq->u.data.pointer, stats,
				sizeof(struct iw_statistics)))
			return -EFAULT;

		/* Check if we need to clear the update flag */
		if(wrq->u.data.flags != 0)
			stats->qual.updated = 0;
		return 0;
	} else
		return -EOPNOTSUPP;
}

/* ---------------------------------------------------------------- */
/*
 * Export the driver private handler definition
 * They will be picked up by tools like iwpriv...
 */
static inline int ioctl_export_private(struct net_device *	dev,
				       struct ifreq *		ifr)
{
	struct iwreq *				iwr = (struct iwreq *) ifr;

	/* Check if the driver has something to export */
	if((dev->wireless_handlers->num_private_args == 0) ||
	   (dev->wireless_handlers->private_args == NULL))
		return -EOPNOTSUPP;

	/* Check NULL pointer */
	if(iwr->u.data.pointer == NULL)
		return -EFAULT;
#ifdef WE_STRICT_WRITE
	/* Check if there is enough buffer up there */
	if(iwr->u.data.length < dev->wireless_handlers->num_private_args) {
		printk(KERN_ERR "%s (WE) : Buffer for request SIOCGIWPRIV too small (%d<%d)\n", dev->name, iwr->u.data.length, dev->wireless_handlers->num_private_args);
		return -E2BIG;
	}
#endif	/* WE_STRICT_WRITE */

	/* Set the number of available ioctls. */
	iwr->u.data.length = dev->wireless_handlers->num_private_args;

	/* Copy structure to the user buffer. */
	if (copy_to_user(iwr->u.data.pointer,
			 dev->wireless_handlers->private_args,
			 sizeof(struct iw_priv_args) * iwr->u.data.length))
		return -EFAULT;

	return 0;
}

/* ---------------------------------------------------------------- */
/*
 * Wrapper to call a standard Wireless Extension handler.
 * We do various checks and also take care of moving data between
 * user space and kernel space.
 */
static inline int ioctl_standard_call(struct net_device *	dev,
				      struct ifreq *		ifr,
				      unsigned int		cmd,
				      iw_handler		handler)
{
	struct iwreq *				iwr = (struct iwreq *) ifr;
	const struct iw_ioctl_description *	descr;
	struct iw_request_info			info;
	int					ret = -EINVAL;
	int					user_size = 0;

	/* Get the description of the IOCTL */
	if((cmd - SIOCIWFIRST) >= standard_ioctl_num)
		return -EOPNOTSUPP;
	descr = &(standard_ioctl[cmd - SIOCIWFIRST]);

#ifdef WE_IOCTL_DEBUG
	printk(KERN_DEBUG "%s (WE) : Found standard handler for 0x%04X\n",
	       ifr->ifr_name, cmd);
	printk(KERN_DEBUG "%s (WE) : Header type : %d, Token type : %d, size : %d, token : %d\n", dev->name, descr->header_type, descr->token_type, descr->token_size, descr->max_tokens);
#endif	/* WE_IOCTL_DEBUG */

	/* Prepare the call */
	info.cmd = cmd;
	info.flags = 0;

	/* Check if we have a pointer to user space data or not */
	if(descr->header_type != IW_HEADER_TYPE_POINT) {

		/* No extra arguments. Trivial to handle */
		ret = handler(dev, &info, &(iwr->u), NULL);

#ifdef WE_SET_EVENT
		/* Generate an event to notify listeners of the change */
		if((descr->flags & IW_DESCR_FLAG_EVENT) &&
		   ((ret == 0) || (ret == -EIWCOMMIT)))
			wireless_send_event(dev, cmd, &(iwr->u), NULL);
#endif	/* WE_SET_EVENT */
	} else {
		char *	extra;
		int	err;

		/* Check what user space is giving us */
		if(IW_IS_SET(cmd)) {
			/* Check NULL pointer */
			if((iwr->u.data.pointer == NULL) &&
			   (iwr->u.data.length != 0))
				return -EFAULT;
			/* Check if number of token fits within bounds */
			if(iwr->u.data.length > descr->max_tokens)
				return -E2BIG;
			if(iwr->u.data.length < descr->min_tokens)
				return -EINVAL;
		} else {
			/* Check NULL pointer */
			if(iwr->u.data.pointer == NULL)
				return -EFAULT;
			/* Save user space buffer size for checking */
			user_size = iwr->u.data.length;
		}

#ifdef WE_IOCTL_DEBUG
		printk(KERN_DEBUG "%s (WE) : Malloc %d bytes\n",
		       dev->name, descr->max_tokens * descr->token_size);
#endif	/* WE_IOCTL_DEBUG */

		/* Always allocate for max space. Easier, and won't last
		 * long... */
		extra = kmalloc(descr->max_tokens * descr->token_size,
				GFP_KERNEL);
		if (extra == NULL) {
			return -ENOMEM;
		}

		/* If it is a SET, get all the extra data in here */
		if(IW_IS_SET(cmd) && (iwr->u.data.length != 0)) {
			err = copy_from_user(extra, iwr->u.data.pointer,
					     iwr->u.data.length *
					     descr->token_size);
			if (err) {
				kfree(extra);
				return -EFAULT;
			}
#ifdef WE_IOCTL_DEBUG
			printk(KERN_DEBUG "%s (WE) : Got %d bytes\n",
			       dev->name,
			       iwr->u.data.length * descr->token_size);
#endif	/* WE_IOCTL_DEBUG */
		}

		/* Call the handler */
		ret = handler(dev, &info, &(iwr->u), extra);

		/* If we have something to return to the user */
		if (!ret && IW_IS_GET(cmd)) {
#ifdef WE_STRICT_WRITE
			/* Check if there is enough buffer up there */
			if(user_size < iwr->u.data.length) {
				printk(KERN_ERR "%s (WE) : Buffer for request %04X too small (%d<%d)\n", dev->name, cmd, user_size, iwr->u.data.length);
				kfree(extra);
				return -E2BIG;
			}
#endif	/* WE_STRICT_WRITE */

			err = copy_to_user(iwr->u.data.pointer, extra,
					   iwr->u.data.length *
					   descr->token_size);
			if (err)
				ret =  -EFAULT;				   
#ifdef WE_IOCTL_DEBUG
			printk(KERN_DEBUG "%s (WE) : Wrote %d bytes\n",
			       dev->name,
			       iwr->u.data.length * descr->token_size);
#endif	/* WE_IOCTL_DEBUG */
		}

#ifdef WE_SET_EVENT
		/* Generate an event to notify listeners of the change */
		if((descr->flags & IW_DESCR_FLAG_EVENT) &&
		   ((ret == 0) || (ret == -EIWCOMMIT))) {
			if(descr->flags & IW_DESCR_FLAG_RESTRICT)
				/* If the event is restricted, don't
				 * export the payload */
				wireless_send_event(dev, cmd, &(iwr->u), NULL);
			else
				wireless_send_event(dev, cmd, &(iwr->u),
						    extra);
		}
#endif	/* WE_SET_EVENT */

		/* Cleanup - I told you it wasn't that long ;-) */
		kfree(extra);
	}

	/* Call commit handler if needed and defined */
	if(ret == -EIWCOMMIT)
		ret = call_commit_handler(dev);

	/* Here, we will generate the appropriate event if needed */

	return ret;
}

/* ---------------------------------------------------------------- */
/*
 * Wrapper to call a private Wireless Extension handler.
 * We do various checks and also take care of moving data between
 * user space and kernel space.
 * It's not as nice and slimline as the standard wrapper. The cause
 * is struct iw_priv_args, which was not really designed for the
 * job we are going here.
 *
 * IMPORTANT : This function prevent to set and get data on the same
 * IOCTL and enforce the SET/GET convention. Not doing it would be
 * far too hairy...
 * If you need to set and get data at the same time, please don't use
 * a iw_handler but process it in your ioctl handler (i.e. use the
 * old driver API).
 */
static inline int ioctl_private_call(struct net_device *	dev,
				     struct ifreq *		ifr,
				     unsigned int		cmd,
				     iw_handler		handler)
{
	struct iwreq *			iwr = (struct iwreq *) ifr;
	struct iw_priv_args *		descr = NULL;
	struct iw_request_info		info;
	int				extra_size = 0;
	int				i;
	int				ret = -EINVAL;

	/* Get the description of the IOCTL */
	for(i = 0; i < dev->wireless_handlers->num_private_args; i++)
		if(cmd == dev->wireless_handlers->private_args[i].cmd) {
			descr = &(dev->wireless_handlers->private_args[i]);
			break;
		}

#ifdef WE_IOCTL_DEBUG
	printk(KERN_DEBUG "%s (WE) : Found private handler for 0x%04X\n",
	       ifr->ifr_name, cmd);
	if(descr) {
		printk(KERN_DEBUG "%s (WE) : Name %s, set %X, get %X\n",
		       dev->name, descr->name,
		       descr->set_args, descr->get_args);
	}
#endif	/* WE_IOCTL_DEBUG */

	/* Compute the size of the set/get arguments */
	if(descr != NULL) {
		if(IW_IS_SET(cmd)) {
			int	offset = 0;	/* For sub-ioctls */
			/* Check for sub-ioctl handler */
			if(descr->name[0] == '\0')
				/* Reserve one int for sub-ioctl index */
				offset = sizeof(__u32);

			/* Size of set arguments */
			extra_size = get_priv_size(descr->set_args);

			/* Does it fits in iwr ? */
			if((descr->set_args & IW_PRIV_SIZE_FIXED) &&
			   ((extra_size + offset) <= IFNAMSIZ))
				extra_size = 0;
		} else {
			/* Size of set arguments */
			extra_size = get_priv_size(descr->get_args);

			/* Does it fits in iwr ? */
			if((descr->get_args & IW_PRIV_SIZE_FIXED) &&
			   (extra_size <= IFNAMSIZ))
				extra_size = 0;
		}
	}

	/* Prepare the call */
	info.cmd = cmd;
	info.flags = 0;

	/* Check if we have a pointer to user space data or not. */
	if(extra_size == 0) {
		/* No extra arguments. Trivial to handle */
		ret = handler(dev, &info, &(iwr->u), (char *) &(iwr->u));
	} else {
		char *	extra;
		int	err;

		/* Check what user space is giving us */
		if(IW_IS_SET(cmd)) {
			/* Check NULL pointer */
			if((iwr->u.data.pointer == NULL) &&
			   (iwr->u.data.length != 0))
				return -EFAULT;

			/* Does it fits within bounds ? */
			if(iwr->u.data.length > (descr->set_args &
						 IW_PRIV_SIZE_MASK))
				return -E2BIG;
		} else {
			/* Check NULL pointer */
			if(iwr->u.data.pointer == NULL)
				return -EFAULT;
		}

#ifdef WE_IOCTL_DEBUG
		printk(KERN_DEBUG "%s (WE) : Malloc %d bytes\n",
		       dev->name, extra_size);
#endif	/* WE_IOCTL_DEBUG */

		/* Always allocate for max space. Easier, and won't last
		 * long... */
		extra = kmalloc(extra_size, GFP_KERNEL);
		if (extra == NULL) {
			return -ENOMEM;
		}

		/* If it is a SET, get all the extra data in here */
		if(IW_IS_SET(cmd) && (iwr->u.data.length != 0)) {
			err = copy_from_user(extra, iwr->u.data.pointer,
					     extra_size);
			if (err) {
				kfree(extra);
				return -EFAULT;
			}
#ifdef WE_IOCTL_DEBUG
			printk(KERN_DEBUG "%s (WE) : Got %d elem\n",
			       dev->name, iwr->u.data.length);
#endif	/* WE_IOCTL_DEBUG */
		}

		/* Call the handler */
		ret = handler(dev, &info, &(iwr->u), extra);

		/* If we have something to return to the user */
		if (!ret && IW_IS_GET(cmd)) {
			err = copy_to_user(iwr->u.data.pointer, extra,
					   extra_size);
			if (err)
				ret =  -EFAULT;				   
#ifdef WE_IOCTL_DEBUG
			printk(KERN_DEBUG "%s (WE) : Wrote %d elem\n",
			       dev->name, iwr->u.data.length);
#endif	/* WE_IOCTL_DEBUG */
		}

		/* Cleanup - I told you it wasn't that long ;-) */
		kfree(extra);
	}


	/* Call commit handler if needed and defined */
	if(ret == -EIWCOMMIT)
		ret = call_commit_handler(dev);

	return ret;
}

/* ---------------------------------------------------------------- */
/*
 * Main IOCTl dispatcher. Called from the main networking code
 * (dev_ioctl() in net/core/dev.c).
 * Check the type of IOCTL and call the appropriate wrapper...
 */
int wireless_process_ioctl(struct ifreq *ifr, unsigned int cmd)
{
	struct net_device *dev;
	iw_handler	handler;

	/* Permissions are already checked in dev_ioctl() before calling us.
	 * The copy_to/from_user() of ifr is also dealt with in there */

	/* Make sure the device exist */
	if ((dev = __dev_get_by_name(ifr->ifr_name)) == NULL)
		return -ENODEV;

	/* A bunch of special cases, then the generic case...
	 * Note that 'cmd' is already filtered in dev_ioctl() with
	 * (cmd >= SIOCIWFIRST && cmd <= SIOCIWLAST) */
	switch(cmd) 
	{
		case SIOCGIWSTATS:
			/* Get Wireless Stats */
			return dev_iwstats(dev, ifr);

		case SIOCGIWPRIV:
			/* Check if we have some wireless handlers defined */
			if(dev->wireless_handlers != NULL) {
				/* We export to user space the definition of
				 * the private handler ourselves */
				return ioctl_export_private(dev, ifr);
			}
			// ## Fall-through for old API ##
		default:
			/* Generic IOCTL */
			/* Basic check */