patch-2.4.19 linux-2.4.19/net/core/wireless.c

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diff -urN linux-2.4.18/net/core/wireless.c linux-2.4.19/net/core/wireless.c
@@ -0,0 +1,733 @@
+/*
+ * This file implement the Wireless Extensions APIs.
+ *
+ * Authors :	Jean Tourrilhes - HPL - <jt@hpl.hp.com>
+ * Copyright (c) 1997-2001 Jean Tourrilhes, All Rights Reserved.
+ *
+ * (As all part of the Linux kernel, this file is GPL)
+ */
+
+/************************** DOCUMENTATION **************************/
+/*
+ * API definition :
+ * --------------
+ * See <linux/wireless.h> for details of the APIs and the rest.
+ *
+ * History :
+ * -------
+ *
+ * v1 - 5.12.01 - Jean II
+ *	o Created this file.
+ *
+ * v2 - 13.12.01 - Jean II
+ *	o Move /proc/net/wireless stuff from net/core/dev.c to here
+ *	o Make Wireless Extension IOCTLs go through here
+ *	o Added iw_handler handling ;-)
+ *	o Added standard ioctl description
+ *	o Initial dumb commit strategy based on orinoco.c
+ */
+
+/***************************** INCLUDES *****************************/
+
+#include <asm/uaccess.h>		/* copy_to_user() */
+#include <linux/config.h>		/* Not needed ??? */
+#include <linux/types.h>		/* off_t */
+#include <linux/netdevice.h>		/* struct ifreq, dev_get_by_name() */
+
+#include <linux/wireless.h>		/* Pretty obvious */
+#include <net/iw_handler.h>		/* New driver API */
+
+/**************************** CONSTANTS ****************************/
+
+/* This will be turned on later on... */
+#undef WE_STRICT_WRITE		/* Check write buffer size */
+
+/* Debuging stuff */
+#undef WE_IOCTL_DEBUG		/* Debug IOCTL API */
+
+/************************* GLOBAL VARIABLES *************************/
+/*
+ * You should not use global variables, because or re-entrancy.
+ * On our case, it's only const, so it's OK...
+ */
+static const struct iw_ioctl_description	standard_ioctl[] = {
+	/* SIOCSIWCOMMIT (internal) */
+	{ IW_HEADER_TYPE_NULL, 0, 0, 0, 0, 0},
+	/* SIOCGIWNAME */
+	{ IW_HEADER_TYPE_CHAR, 0, 0, 0, 0, IW_DESCR_FLAG_DUMP},
+	/* SIOCSIWNWID */
+	{ IW_HEADER_TYPE_PARAM, 0, 0, 0, 0, IW_DESCR_FLAG_EVENT},
+	/* SIOCGIWNWID */
+	{ IW_HEADER_TYPE_PARAM, 0, 0, 0, 0, IW_DESCR_FLAG_DUMP},
+	/* SIOCSIWFREQ */
+	{ IW_HEADER_TYPE_FREQ, 0, 0, 0, 0, IW_DESCR_FLAG_EVENT},
+	/* SIOCGIWFREQ */
+	{ IW_HEADER_TYPE_FREQ, 0, 0, 0, 0, IW_DESCR_FLAG_DUMP},
+	/* SIOCSIWMODE */
+	{ IW_HEADER_TYPE_UINT, 0, 0, 0, 0, IW_DESCR_FLAG_EVENT},
+	/* SIOCGIWMODE */
+	{ IW_HEADER_TYPE_UINT, 0, 0, 0, 0, IW_DESCR_FLAG_DUMP},
+	/* SIOCSIWSENS */
+	{ IW_HEADER_TYPE_PARAM, 0, 0, 0, 0, 0},
+	/* SIOCGIWSENS */
+	{ IW_HEADER_TYPE_PARAM, 0, 0, 0, 0, 0},
+	/* SIOCSIWRANGE */
+	{ IW_HEADER_TYPE_NULL, 0, 0, 0, 0, 0},
+	/* SIOCGIWRANGE */
+	{ IW_HEADER_TYPE_POINT, 0, 1, 0, sizeof(struct iw_range), IW_DESCR_FLAG_DUMP},
+	/* SIOCSIWPRIV */
+	{ IW_HEADER_TYPE_NULL, 0, 0, 0, 0, 0},
+	/* SIOCGIWPRIV (handled directly by us) */
+	{ IW_HEADER_TYPE_NULL, 0, 0, 0, 0, 0},
+	/* SIOCSIWSTATS */
+	{ IW_HEADER_TYPE_NULL, 0, 0, 0, 0, 0},
+	/* SIOCGIWSTATS (handled directly by us) */
+	{ IW_HEADER_TYPE_NULL, 0, 0, 0, 0, IW_DESCR_FLAG_DUMP},
+	/* SIOCSIWSPY */
+	{ IW_HEADER_TYPE_POINT, 0, sizeof(struct sockaddr), 0, IW_MAX_SPY, 0},
+	/* SIOCGIWSPY */
+	{ IW_HEADER_TYPE_POINT, 0, (sizeof(struct sockaddr) + sizeof(struct iw_quality)), 0, IW_MAX_SPY, 0},
+	/* -- hole -- */
+	{ IW_HEADER_TYPE_NULL, 0, 0, 0, 0, 0},
+	/* -- hole -- */
+	{ IW_HEADER_TYPE_NULL, 0, 0, 0, 0, 0},
+	/* SIOCSIWAP */
+	{ IW_HEADER_TYPE_ADDR, 0, 0, 0, 0, 0},
+	/* SIOCGIWAP */
+	{ IW_HEADER_TYPE_ADDR, 0, 0, 0, 0, IW_DESCR_FLAG_DUMP},
+	/* -- hole -- */
+	{ IW_HEADER_TYPE_NULL, 0, 0, 0, 0, 0},
+	/* SIOCGIWAPLIST */
+	{ IW_HEADER_TYPE_POINT, 0, (sizeof(struct sockaddr) + sizeof(struct iw_quality)), 0, IW_MAX_AP, 0},
+	/* -- hole -- */
+	{ IW_HEADER_TYPE_NULL, 0, 0, 0, 0, 0},
+	/* -- hole -- */
+	{ IW_HEADER_TYPE_NULL, 0, 0, 0, 0, 0},
+	/* SIOCSIWESSID */
+	{ IW_HEADER_TYPE_POINT, 0, 1, 0, IW_ESSID_MAX_SIZE, IW_DESCR_FLAG_EVENT},
+	/* SIOCGIWESSID */
+	{ IW_HEADER_TYPE_POINT, 0, 1, 0, IW_ESSID_MAX_SIZE, IW_DESCR_FLAG_DUMP},
+	/* SIOCSIWNICKN */
+	{ IW_HEADER_TYPE_POINT, 0, 1, 0, IW_ESSID_MAX_SIZE, 0},
+	/* SIOCGIWNICKN */
+	{ IW_HEADER_TYPE_POINT, 0, 1, 0, IW_ESSID_MAX_SIZE, 0},
+	/* -- hole -- */
+	{ IW_HEADER_TYPE_NULL, 0, 0, 0, 0, 0},
+	/* -- hole -- */
+	{ IW_HEADER_TYPE_NULL, 0, 0, 0, 0, 0},
+	/* SIOCSIWRATE */
+	{ IW_HEADER_TYPE_PARAM, 0, 0, 0, 0, 0},
+	/* SIOCGIWRATE */
+	{ IW_HEADER_TYPE_PARAM, 0, 0, 0, 0, 0},
+	/* SIOCSIWRTS */
+	{ IW_HEADER_TYPE_PARAM, 0, 0, 0, 0, 0},
+	/* SIOCGIWRTS */
+	{ IW_HEADER_TYPE_PARAM, 0, 0, 0, 0, 0},
+	/* SIOCSIWFRAG */
+	{ IW_HEADER_TYPE_PARAM, 0, 0, 0, 0, 0},
+	/* SIOCGIWFRAG */
+	{ IW_HEADER_TYPE_PARAM, 0, 0, 0, 0, 0},
+	/* SIOCSIWTXPOW */
+	{ IW_HEADER_TYPE_PARAM, 0, 0, 0, 0, 0},
+	/* SIOCGIWTXPOW */
+	{ IW_HEADER_TYPE_PARAM, 0, 0, 0, 0, 0},
+	/* SIOCSIWRETRY */
+	{ IW_HEADER_TYPE_PARAM, 0, 0, 0, 0, 0},
+	/* SIOCGIWRETRY */
+	{ IW_HEADER_TYPE_PARAM, 0, 0, 0, 0, 0},
+	/* SIOCSIWENCODE */
+	{ IW_HEADER_TYPE_POINT, 4, 1, 0, IW_ENCODING_TOKEN_MAX, IW_DESCR_FLAG_EVENT | IW_DESCR_FLAG_RESTRICT},
+	/* SIOCGIWENCODE */
+	{ IW_HEADER_TYPE_POINT, 0, 1, 0, IW_ENCODING_TOKEN_MAX, IW_DESCR_FLAG_DUMP | IW_DESCR_FLAG_RESTRICT},
+	/* SIOCSIWPOWER */
+	{ IW_HEADER_TYPE_PARAM, 0, 0, 0, 0, 0},
+	/* SIOCGIWPOWER */
+	{ IW_HEADER_TYPE_PARAM, 0, 0, 0, 0, 0},
+};
+
+/* Size (in bytes) of the various private data types */
+char priv_type_size[] = { 0, 1, 1, 0, 4, 4, 0, 0 };
+
+/************************ COMMON SUBROUTINES ************************/
+/*
+ * Stuff that may be used in various place or doesn't fit in one
+ * of the section below.
+ */
+
+/* ---------------------------------------------------------------- */
+/*
+ * Return the driver handler associated with a specific Wireless Extension.
+ * Called from various place, so make sure it remains efficient.
+ */
+static inline iw_handler get_handler(struct net_device *dev,
+				     unsigned int cmd)
+{
+	unsigned int	index;		/* MUST be unsigned */
+
+	/* Check if we have some wireless handlers defined */
+	if(dev->wireless_handlers == NULL)
+		return NULL;
+
+	/* Try as a standard command */
+	index = cmd - SIOCIWFIRST;
+	if(index < dev->wireless_handlers->num_standard)
+		return dev->wireless_handlers->standard[index];
+
+	/* Try as a private command */
+	index = cmd - SIOCIWFIRSTPRIV;
+	if(index < dev->wireless_handlers->num_private)
+		return dev->wireless_handlers->private[index];
+
+	/* Not found */
+	return NULL;
+}
+
+/* ---------------------------------------------------------------- */
+/*
+ * Get statistics out of the driver
+ */
+static inline struct iw_statistics *get_wireless_stats(struct net_device *dev)
+{
+	return (dev->get_wireless_stats ?
+		dev->get_wireless_stats(dev) :
+		(struct iw_statistics *) NULL);
+	/* In the future, get_wireless_stats may move from 'struct net_device'
+	 * to 'struct iw_handler_def', to de-bloat struct net_device.
+	 * Definitely worse a thought... */
+}
+
+/* ---------------------------------------------------------------- */
+/*
+ * Call the commit handler in the driver
+ * (if exist and if conditions are right)
+ *
+ * Note : our current commit strategy is currently pretty dumb,
+ * but we will be able to improve on that...
+ * The goal is to try to agreagate as many changes as possible
+ * before doing the commit. Drivers that will define a commit handler
+ * are usually those that need a reset after changing parameters, so
+ * we want to minimise the number of reset.
+ * A cool idea is to use a timer : at each "set" command, we re-set the
+ * timer, when the timer eventually fires, we call the driver.
+ * Hopefully, more on that later.
+ *
+ * Also, I'm waiting to see how many people will complain about the
+ * netif_running(dev) test. I'm open on that one...
+ * Hopefully, the driver will remember to do a commit in "open()" ;-)
+ */
+static inline int call_commit_handler(struct net_device *	dev)
+{
+	if((netif_running(dev)) &&
+	   (dev->wireless_handlers->standard[0] != NULL)) {
+		/* Call the commit handler on the driver */
+		return dev->wireless_handlers->standard[0](dev, NULL,
+							   NULL, NULL);
+	} else
+		return 0;		/* Command completed successfully */
+}
+
+/* ---------------------------------------------------------------- */
+/*
+ * Number of private arguments
+ */
+static inline int get_priv_size(__u16	args)
+{
+	int	num = args & IW_PRIV_SIZE_MASK;
+	int	type = (args & IW_PRIV_TYPE_MASK) >> 12;
+
+	return num * priv_type_size[type];
+}
+
+
+/******************** /proc/net/wireless SUPPORT ********************/
+/*
+ * The /proc/net/wireless file is a human readable user-space interface
+ * exporting various wireless specific statistics from the wireless devices.
+ * This is the most popular part of the Wireless Extensions ;-)
+ *
+ * This interface is a pure clone of /proc/net/dev (in net/core/dev.c).
+ * The content of the file is basically the content of "struct iw_statistics".
+ */
+
+#ifdef CONFIG_PROC_FS
+
+/* ---------------------------------------------------------------- */
+/*
+ * Print one entry (line) of /proc/net/wireless
+ */
+static inline int sprintf_wireless_stats(char *buffer, struct net_device *dev)
+{
+	/* Get stats from the driver */
+	struct iw_statistics *stats;
+	int size;
+
+	stats = get_wireless_stats(dev);
+	if (stats != (struct iw_statistics *) NULL) {
+		size = sprintf(buffer,
+			       "%6s: %04x  %3d%c  %3d%c  %3d%c  %6d %6d %6d %6d %6d   %6d\n",
+			       dev->name,
+			       stats->status,
+			       stats->qual.qual,
+			       stats->qual.updated & 1 ? '.' : ' ',
+			       stats->qual.level,
+			       stats->qual.updated & 2 ? '.' : ' ',
+			       stats->qual.noise,
+			       stats->qual.updated & 4 ? '.' : ' ',
+			       stats->discard.nwid,
+			       stats->discard.code,
+			       stats->discard.fragment,
+			       stats->discard.retries,
+			       stats->discard.misc,
+			       stats->miss.beacon);
+		stats->qual.updated = 0;
+	}
+	else
+		size = 0;
+
+	return size;
+}
+
+/* ---------------------------------------------------------------- */
+/*
+ * Print info for /proc/net/wireless (print all entries)
+ */
+int dev_get_wireless_info(char * buffer, char **start, off_t offset,
+			  int length)
+{
+	int		len = 0;
+	off_t		begin = 0;
+	off_t		pos = 0;
+	int		size;
+	
+	struct net_device *	dev;
+
+	size = sprintf(buffer,
+		       "Inter-| sta-|   Quality        |   Discarded packets               | Missed\n"
+		       " face | tus | link level noise |  nwid  crypt   frag  retry   misc | beacon\n"
+			);
+	
+	pos += size;
+	len += size;
+
+	read_lock(&dev_base_lock);
+	for (dev = dev_base; dev != NULL; dev = dev->next) {
+		size = sprintf_wireless_stats(buffer + len, dev);
+		len += size;
+		pos = begin + len;
+
+		if (pos < offset) {
+			len = 0;
+			begin = pos;
+		}
+		if (pos > offset + length)
+			break;
+	}
+	read_unlock(&dev_base_lock);
+
+	*start = buffer + (offset - begin);	/* Start of wanted data */
+	len -= (offset - begin);		/* Start slop */
+	if (len > length)
+		len = length;			/* Ending slop */
+	if (len < 0)
+		len = 0;
+
+	return len;
+}
+#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 < (SIOCIWLASTPRIV - SIOCIWFIRSTPRIV + 1))
+		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;
+
+	/* Get the description of the IOCTL */
+	descr = &(standard_ioctl[cmd - SIOCIWFIRST]);
+
+#ifdef WE_IOCTL_DEBUG
+	printk(KERN_DEBUG "%s : Found standard handler for 0x%04X\n",
+	       ifr->ifr_name, cmd);
+	printk(KERN_DEBUG "Header type : %d, token type : %d, token_size : %d, max_token : %d\n", 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);
+	} 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;
+#ifdef WE_STRICT_WRITE
+			/* Check if there is enough buffer up there */
+			if(iwr->u.data.length < descr->max_tokens)
+				return -E2BIG;
+#endif	/* WE_STRICT_WRITE */
+		}
+
+#ifdef WE_IOCTL_DEBUG
+		printk(KERN_DEBUG "Malloc %d bytes\n",
+		       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 "Got %d bytes\n",
+			       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)) {
+			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 "Wrote %d bytes\n",
+			       iwr->u.data.length * descr->token_size);
+#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);
+
+	/* 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 : Found private handler for 0x%04X\n",
+	       ifr->ifr_name, cmd);
+	if(descr) {
+		printk(KERN_DEBUG "Name %s, set %X, get %X\n",
+		       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)) {
+			/* 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 < 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 "Malloc %d bytes\n", 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 "Got %d elem\n", 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 "Wrote %d elem\n",
+			       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 */
+			if (!netif_device_present(dev))
+				return -ENODEV;
+			/* New driver API : try to find the handler */
+			handler = get_handler(dev, cmd);
+			if(handler != NULL) {
+				/* Standard and private are not the same */
+				if(cmd < SIOCIWFIRSTPRIV)
+					return ioctl_standard_call(dev,
+								   ifr,
+								   cmd,
+								   handler);
+				else
+					return ioctl_private_call(dev,
+								  ifr,
+								  cmd,
+								  handler);
+			}
+			/* Old driver API : call driver ioctl handler */
+			if (dev->do_ioctl) {
+				return dev->do_ioctl(dev, ifr, cmd);
+			}
+			return -EOPNOTSUPP;
+	}
+	/* Not reached */
+	return -EINVAL;
+}

FUNET's LINUX-ADM group, linux-adm@nic.funet.fi
TCL-scripts by Sam Shen (who was at: slshen@lbl.gov)