wext: refactor

Refactor wext to
 * split out iwpriv handling
 * split out iwspy handling
 * split out procfs support
 * allow cfg80211 to have wireless extensions compat code
   w/o CONFIG_WIRELESS_EXT

After this, drivers need to
 - select WIRELESS_EXT	- for wext support
 - select WEXT_PRIV	- for iwpriv support
 - select WEXT_SPY	- for iwspy support

except cfg80211 -- which gets new hooks in wext-core.c
and can then get wext handlers without CONFIG_WIRELESS_EXT.

Wireless extensions procfs support is auto-selected
based on PROC_FS and anything that requires the wext core
(i.e. WIRELESS_EXT or CFG80211_WEXT).

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 1063 insertions, 0 deletions

diff --git a/net/wireless/wext-core.c b/net/wireless/wext-core.c
new file mode 100644
index 000000000000..a4e5ddc8d4f5
--- /dev/null
+++ b/net/wireless/wext-core.c
@@ -0,0 +1,1063 @@
+/*
+ * This file implement the Wireless Extensions core API.
+ *
+ * Authors :	Jean Tourrilhes - HPL - <jt@hpl.hp.com>
+ * Copyright (c) 1997-2007 Jean Tourrilhes, All Rights Reserved.
+ * Copyright	2009 Johannes Berg <johannes@sipsolutions.net>
+ *
+ * (As all part of the Linux kernel, this file is GPL)
+ */
+#include <linux/kernel.h>
+#include <linux/netdevice.h>
+#include <linux/rtnetlink.h>
+#include <linux/wireless.h>
+#include <linux/uaccess.h>
+#include <net/cfg80211.h>
+#include <net/iw_handler.h>
+#include <net/netlink.h>
+#include <net/wext.h>
+#include <net/net_namespace.h>
+
+typedef int (*wext_ioctl_func)(struct net_device *, struct iwreq *,
+			       unsigned int, struct iw_request_info *,
+			       iw_handler);
+
+
+/*
+ * Meta-data about all the standard Wireless Extension request we
+ * know about.
+ */
+static const struct iw_ioctl_description standard_ioctl[] = {
+	[SIOCSIWCOMMIT	- SIOCIWFIRST] = {
+		.header_type	= IW_HEADER_TYPE_NULL,
+	},
+	[SIOCGIWNAME	- SIOCIWFIRST] = {
+		.header_type	= IW_HEADER_TYPE_CHAR,
+		.flags		= IW_DESCR_FLAG_DUMP,
+	},
+	[SIOCSIWNWID	- SIOCIWFIRST] = {
+		.header_type	= IW_HEADER_TYPE_PARAM,
+		.flags		= IW_DESCR_FLAG_EVENT,
+	},
+	[SIOCGIWNWID	- SIOCIWFIRST] = {
+		.header_type	= IW_HEADER_TYPE_PARAM,
+		.flags		= IW_DESCR_FLAG_DUMP,
+	},
+	[SIOCSIWFREQ	- SIOCIWFIRST] = {
+		.header_type	= IW_HEADER_TYPE_FREQ,
+		.flags		= IW_DESCR_FLAG_EVENT,
+	},
+	[SIOCGIWFREQ	- SIOCIWFIRST] = {
+		.header_type	= IW_HEADER_TYPE_FREQ,
+		.flags		= IW_DESCR_FLAG_DUMP,
+	},
+	[SIOCSIWMODE	- SIOCIWFIRST] = {
+		.header_type	= IW_HEADER_TYPE_UINT,
+		.flags		= IW_DESCR_FLAG_EVENT,
+	},
+	[SIOCGIWMODE	- SIOCIWFIRST] = {
+		.header_type	= IW_HEADER_TYPE_UINT,
+		.flags		= IW_DESCR_FLAG_DUMP,
+	},
+	[SIOCSIWSENS	- SIOCIWFIRST] = {
+		.header_type	= IW_HEADER_TYPE_PARAM,
+	},
+	[SIOCGIWSENS	- SIOCIWFIRST] = {
+		.header_type	= IW_HEADER_TYPE_PARAM,
+	},
+	[SIOCSIWRANGE	- SIOCIWFIRST] = {
+		.header_type	= IW_HEADER_TYPE_NULL,
+	},
+	[SIOCGIWRANGE	- SIOCIWFIRST] = {
+		.header_type	= IW_HEADER_TYPE_POINT,
+		.token_size	= 1,
+		.max_tokens	= sizeof(struct iw_range),
+		.flags		= IW_DESCR_FLAG_DUMP,
+	},
+	[SIOCSIWPRIV	- SIOCIWFIRST] = {
+		.header_type	= IW_HEADER_TYPE_NULL,
+	},
+	[SIOCGIWPRIV	- SIOCIWFIRST] = { /* (handled directly by us) */
+		.header_type	= IW_HEADER_TYPE_POINT,
+		.token_size	= sizeof(struct iw_priv_args),
+		.max_tokens	= 16,
+		.flags		= IW_DESCR_FLAG_NOMAX,
+	},
+	[SIOCSIWSTATS	- SIOCIWFIRST] = {
+		.header_type	= IW_HEADER_TYPE_NULL,
+	},
+	[SIOCGIWSTATS	- SIOCIWFIRST] = { /* (handled directly by us) */
+		.header_type	= IW_HEADER_TYPE_POINT,
+		.token_size	= 1,
+		.max_tokens	= sizeof(struct iw_statistics),
+		.flags		= IW_DESCR_FLAG_DUMP,
+	},
+	[SIOCSIWSPY	- SIOCIWFIRST] = {
+		.header_type	= IW_HEADER_TYPE_POINT,
+		.token_size	= sizeof(struct sockaddr),
+		.max_tokens	= IW_MAX_SPY,
+	},
+	[SIOCGIWSPY	- SIOCIWFIRST] = {
+		.header_type	= IW_HEADER_TYPE_POINT,
+		.token_size	= sizeof(struct sockaddr) +
+				  sizeof(struct iw_quality),
+		.max_tokens	= IW_MAX_SPY,
+	},
+	[SIOCSIWTHRSPY	- SIOCIWFIRST] = {
+		.header_type	= IW_HEADER_TYPE_POINT,
+		.token_size	= sizeof(struct iw_thrspy),
+		.min_tokens	= 1,
+		.max_tokens	= 1,
+	},
+	[SIOCGIWTHRSPY	- SIOCIWFIRST] = {
+		.header_type	= IW_HEADER_TYPE_POINT,
+		.token_size	= sizeof(struct iw_thrspy),
+		.min_tokens	= 1,
+		.max_tokens	= 1,
+	},
+	[SIOCSIWAP	- SIOCIWFIRST] = {
+		.header_type	= IW_HEADER_TYPE_ADDR,
+	},
+	[SIOCGIWAP	- SIOCIWFIRST] = {
+		.header_type	= IW_HEADER_TYPE_ADDR,
+		.flags		= IW_DESCR_FLAG_DUMP,
+	},
+	[SIOCSIWMLME	- SIOCIWFIRST] = {
+		.header_type	= IW_HEADER_TYPE_POINT,
+		.token_size	= 1,
+		.min_tokens	= sizeof(struct iw_mlme),
+		.max_tokens	= sizeof(struct iw_mlme),
+	},
+	[SIOCGIWAPLIST	- SIOCIWFIRST] = {
+		.header_type	= IW_HEADER_TYPE_POINT,
+		.token_size	= sizeof(struct sockaddr) +
+				  sizeof(struct iw_quality),
+		.max_tokens	= IW_MAX_AP,
+		.flags		= IW_DESCR_FLAG_NOMAX,
+	},
+	[SIOCSIWSCAN	- SIOCIWFIRST] = {
+		.header_type	= IW_HEADER_TYPE_POINT,
+		.token_size	= 1,
+		.min_tokens	= 0,
+		.max_tokens	= sizeof(struct iw_scan_req),
+	},
+	[SIOCGIWSCAN	- SIOCIWFIRST] = {
+		.header_type	= IW_HEADER_TYPE_POINT,
+		.token_size	= 1,
+		.max_tokens	= IW_SCAN_MAX_DATA,
+		.flags		= IW_DESCR_FLAG_NOMAX,
+	},
+	[SIOCSIWESSID	- SIOCIWFIRST] = {
+		.header_type	= IW_HEADER_TYPE_POINT,
+		.token_size	= 1,
+		.max_tokens	= IW_ESSID_MAX_SIZE,
+		.flags		= IW_DESCR_FLAG_EVENT,
+	},
+	[SIOCGIWESSID	- SIOCIWFIRST] = {
+		.header_type	= IW_HEADER_TYPE_POINT,
+		.token_size	= 1,
+		.max_tokens	= IW_ESSID_MAX_SIZE,
+		.flags		= IW_DESCR_FLAG_DUMP,
+	},
+	[SIOCSIWNICKN	- SIOCIWFIRST] = {
+		.header_type	= IW_HEADER_TYPE_POINT,
+		.token_size	= 1,
+		.max_tokens	= IW_ESSID_MAX_SIZE,
+	},
+	[SIOCGIWNICKN	- SIOCIWFIRST] = {
+		.header_type	= IW_HEADER_TYPE_POINT,
+		.token_size	= 1,
+		.max_tokens	= IW_ESSID_MAX_SIZE,
+	},
+	[SIOCSIWRATE	- SIOCIWFIRST] = {
+		.header_type	= IW_HEADER_TYPE_PARAM,
+	},
+	[SIOCGIWRATE	- SIOCIWFIRST] = {
+		.header_type	= IW_HEADER_TYPE_PARAM,
+	},
+	[SIOCSIWRTS	- SIOCIWFIRST] = {
+		.header_type	= IW_HEADER_TYPE_PARAM,
+	},
+	[SIOCGIWRTS	- SIOCIWFIRST] = {
+		.header_type	= IW_HEADER_TYPE_PARAM,
+	},
+	[SIOCSIWFRAG	- SIOCIWFIRST] = {
+		.header_type	= IW_HEADER_TYPE_PARAM,
+	},
+	[SIOCGIWFRAG	- SIOCIWFIRST] = {
+		.header_type	= IW_HEADER_TYPE_PARAM,
+	},
+	[SIOCSIWTXPOW	- SIOCIWFIRST] = {
+		.header_type	= IW_HEADER_TYPE_PARAM,
+	},
+	[SIOCGIWTXPOW	- SIOCIWFIRST] = {
+		.header_type	= IW_HEADER_TYPE_PARAM,
+	},
+	[SIOCSIWRETRY	- SIOCIWFIRST] = {
+		.header_type	= IW_HEADER_TYPE_PARAM,
+	},
+	[SIOCGIWRETRY	- SIOCIWFIRST] = {
+		.header_type	= IW_HEADER_TYPE_PARAM,
+	},
+	[SIOCSIWENCODE	- SIOCIWFIRST] = {
+		.header_type	= IW_HEADER_TYPE_POINT,
+		.token_size	= 1,
+		.max_tokens	= IW_ENCODING_TOKEN_MAX,
+		.flags		= IW_DESCR_FLAG_EVENT | IW_DESCR_FLAG_RESTRICT,
+	},
+	[SIOCGIWENCODE	- SIOCIWFIRST] = {
+		.header_type	= IW_HEADER_TYPE_POINT,
+		.token_size	= 1,
+		.max_tokens	= IW_ENCODING_TOKEN_MAX,
+		.flags		= IW_DESCR_FLAG_DUMP | IW_DESCR_FLAG_RESTRICT,
+	},
+	[SIOCSIWPOWER	- SIOCIWFIRST] = {
+		.header_type	= IW_HEADER_TYPE_PARAM,
+	},
+	[SIOCGIWPOWER	- SIOCIWFIRST] = {
+		.header_type	= IW_HEADER_TYPE_PARAM,
+	},
+	[SIOCSIWGENIE	- SIOCIWFIRST] = {
+		.header_type	= IW_HEADER_TYPE_POINT,
+		.token_size	= 1,
+		.max_tokens	= IW_GENERIC_IE_MAX,
+	},
+	[SIOCGIWGENIE	- SIOCIWFIRST] = {
+		.header_type	= IW_HEADER_TYPE_POINT,
+		.token_size	= 1,
+		.max_tokens	= IW_GENERIC_IE_MAX,
+	},
+	[SIOCSIWAUTH	- SIOCIWFIRST] = {
+		.header_type	= IW_HEADER_TYPE_PARAM,
+	},
+	[SIOCGIWAUTH	- SIOCIWFIRST] = {
+		.header_type	= IW_HEADER_TYPE_PARAM,
+	},
+	[SIOCSIWENCODEEXT - SIOCIWFIRST] = {
+		.header_type	= IW_HEADER_TYPE_POINT,
+		.token_size	= 1,
+		.min_tokens	= sizeof(struct iw_encode_ext),
+		.max_tokens	= sizeof(struct iw_encode_ext) +
+				  IW_ENCODING_TOKEN_MAX,
+	},
+	[SIOCGIWENCODEEXT - SIOCIWFIRST] = {
+		.header_type	= IW_HEADER_TYPE_POINT,
+		.token_size	= 1,
+		.min_tokens	= sizeof(struct iw_encode_ext),
+		.max_tokens	= sizeof(struct iw_encode_ext) +
+				  IW_ENCODING_TOKEN_MAX,
+	},
+	[SIOCSIWPMKSA - SIOCIWFIRST] = {
+		.header_type	= IW_HEADER_TYPE_POINT,
+		.token_size	= 1,
+		.min_tokens	= sizeof(struct iw_pmksa),
+		.max_tokens	= sizeof(struct iw_pmksa),
+	},
+};
+static const unsigned standard_ioctl_num = ARRAY_SIZE(standard_ioctl);
+
+/*
+ * Meta-data about all the additional standard Wireless Extension events
+ * we know about.
+ */
+static const struct iw_ioctl_description standard_event[] = {
+	[IWEVTXDROP	- IWEVFIRST] = {
+		.header_type	= IW_HEADER_TYPE_ADDR,
+	},
+	[IWEVQUAL	- IWEVFIRST] = {
+		.header_type	= IW_HEADER_TYPE_QUAL,
+	},
+	[IWEVCUSTOM	- IWEVFIRST] = {
+		.header_type	= IW_HEADER_TYPE_POINT,
+		.token_size	= 1,
+		.max_tokens	= IW_CUSTOM_MAX,
+	},
+	[IWEVREGISTERED	- IWEVFIRST] = {
+		.header_type	= IW_HEADER_TYPE_ADDR,
+	},
+	[IWEVEXPIRED	- IWEVFIRST] = {
+		.header_type	= IW_HEADER_TYPE_ADDR,
+	},
+	[IWEVGENIE	- IWEVFIRST] = {
+		.header_type	= IW_HEADER_TYPE_POINT,
+		.token_size	= 1,
+		.max_tokens	= IW_GENERIC_IE_MAX,
+	},
+	[IWEVMICHAELMICFAILURE	- IWEVFIRST] = {
+		.header_type	= IW_HEADER_TYPE_POINT,
+		.token_size	= 1,
+		.max_tokens	= sizeof(struct iw_michaelmicfailure),
+	},
+	[IWEVASSOCREQIE	- IWEVFIRST] = {
+		.header_type	= IW_HEADER_TYPE_POINT,
+		.token_size	= 1,
+		.max_tokens	= IW_GENERIC_IE_MAX,
+	},
+	[IWEVASSOCRESPIE	- IWEVFIRST] = {
+		.header_type	= IW_HEADER_TYPE_POINT,
+		.token_size	= 1,
+		.max_tokens	= IW_GENERIC_IE_MAX,
+	},
+	[IWEVPMKIDCAND	- IWEVFIRST] = {
+		.header_type	= IW_HEADER_TYPE_POINT,
+		.token_size	= 1,
+		.max_tokens	= sizeof(struct iw_pmkid_cand),
+	},
+};
+static const unsigned standard_event_num = ARRAY_SIZE(standard_event);
+
+/* Size (in bytes) of various events */
+static const int event_type_size[] = {
+	IW_EV_LCP_LEN,			/* IW_HEADER_TYPE_NULL */
+	0,
+	IW_EV_CHAR_LEN,			/* IW_HEADER_TYPE_CHAR */
+	0,
+	IW_EV_UINT_LEN,			/* IW_HEADER_TYPE_UINT */
+	IW_EV_FREQ_LEN,			/* IW_HEADER_TYPE_FREQ */
+	IW_EV_ADDR_LEN,			/* IW_HEADER_TYPE_ADDR */
+	0,
+	IW_EV_POINT_LEN,		/* Without variable payload */
+	IW_EV_PARAM_LEN,		/* IW_HEADER_TYPE_PARAM */
+	IW_EV_QUAL_LEN,			/* IW_HEADER_TYPE_QUAL */
+};
+
+#ifdef CONFIG_COMPAT
+static const int compat_event_type_size[] = {
+	IW_EV_COMPAT_LCP_LEN,		/* IW_HEADER_TYPE_NULL */
+	0,
+	IW_EV_COMPAT_CHAR_LEN,		/* IW_HEADER_TYPE_CHAR */
+	0,
+	IW_EV_COMPAT_UINT_LEN,		/* IW_HEADER_TYPE_UINT */
+	IW_EV_COMPAT_FREQ_LEN,		/* IW_HEADER_TYPE_FREQ */
+	IW_EV_COMPAT_ADDR_LEN,		/* IW_HEADER_TYPE_ADDR */
+	0,
+	IW_EV_COMPAT_POINT_LEN,		/* Without variable payload */
+	IW_EV_COMPAT_PARAM_LEN,		/* IW_HEADER_TYPE_PARAM */
+	IW_EV_COMPAT_QUAL_LEN,		/* IW_HEADER_TYPE_QUAL */
+};
+#endif
+
+
+/* IW event code */
+
+static int __net_init wext_pernet_init(struct net *net)
+{
+	skb_queue_head_init(&net->wext_nlevents);
+	return 0;
+}
+
+static void __net_exit wext_pernet_exit(struct net *net)
+{
+	skb_queue_purge(&net->wext_nlevents);
+}
+
+static struct pernet_operations wext_pernet_ops = {
+	.init = wext_pernet_init,
+	.exit = wext_pernet_exit,
+};
+
+static int __init wireless_nlevent_init(void)
+{
+	return register_pernet_subsys(&wext_pernet_ops);
+}
+
+subsys_initcall(wireless_nlevent_init);
+
+/* Process events generated by the wireless layer or the driver. */
+static void wireless_nlevent_process(struct work_struct *work)
+{
+	struct sk_buff *skb;
+	struct net *net;
+
+	rtnl_lock();
+
+	for_each_net(net) {
+		while ((skb = skb_dequeue(&net->wext_nlevents)))
+			rtnl_notify(skb, net, 0, RTNLGRP_LINK, NULL,
+				    GFP_KERNEL);
+	}
+
+	rtnl_unlock();
+}
+
+static DECLARE_WORK(wireless_nlevent_work, wireless_nlevent_process);
+
+static struct nlmsghdr *rtnetlink_ifinfo_prep(struct net_device *dev,
+					      struct sk_buff *skb)
+{
+	struct ifinfomsg *r;
+	struct nlmsghdr  *nlh;
+
+	nlh = nlmsg_put(skb, 0, 0, RTM_NEWLINK, sizeof(*r), 0);
+	if (!nlh)
+		return NULL;
+
+	r = nlmsg_data(nlh);
+	r->ifi_family = AF_UNSPEC;
+	r->__ifi_pad = 0;
+	r->ifi_type = dev->type;
+	r->ifi_index = dev->ifindex;
+	r->ifi_flags = dev_get_flags(dev);
+	r->ifi_change = 0;	/* Wireless changes don't affect those flags */
+
+	NLA_PUT_STRING(skb, IFLA_IFNAME, dev->name);
+
+	return nlh;
+ nla_put_failure:
+	nlmsg_cancel(skb, nlh);
+	return NULL;
+}
+
+
+/*
+ * Main event dispatcher. Called from other parts and drivers.
+ * Send the event on the appropriate channels.
+ * May be called from interrupt context.
+ */
+void wireless_send_event(struct net_device *	dev,
+			 unsigned int		cmd,
+			 union iwreq_data *	wrqu,
+			 const char *		extra)
+{
+	const struct iw_ioctl_description *	descr = NULL;
+	int extra_len = 0;
+	struct iw_event  *event;		/* Mallocated whole event */
+	int event_len;				/* Its size */
+	int hdr_len;				/* Size of the event header */
+	int wrqu_off = 0;			/* Offset in wrqu */
+	/* Don't "optimise" the following variable, it will crash */
+	unsigned	cmd_index;		/* *MUST* be unsigned */
+	struct sk_buff *skb;
+	struct nlmsghdr *nlh;
+	struct nlattr *nla;
+#ifdef CONFIG_COMPAT
+	struct __compat_iw_event *compat_event;
+	struct compat_iw_point compat_wrqu;
+	struct sk_buff *compskb;
+#endif
+
+	/*
+	 * Nothing in the kernel sends scan events with data, be safe.
+	 * This is necessary because we cannot fix up scan event data
+	 * for compat, due to being contained in 'extra', but normally
+	 * applications are required to retrieve the scan data anyway
+	 * and no data is included in the event, this codifies that
+	 * practice.
+	 */
+	if (WARN_ON(cmd == SIOCGIWSCAN && extra))
+		extra = NULL;
+
+	/* Get the description of the Event */
+	if (cmd <= SIOCIWLAST) {
+		cmd_index = cmd - SIOCIWFIRST;
+		if (cmd_index < standard_ioctl_num)
+			descr = &(standard_ioctl[cmd_index]);
+	} else {
+		cmd_index = cmd - IWEVFIRST;
+		if (cmd_index < standard_event_num)
+			descr = &(standard_event[cmd_index]);
+	}
+	/* Don't accept unknown events */
+	if (descr == NULL) {
+		/* Note : we don't return an error to the driver, because
+		 * the driver would not know what to do about it. It can't
+		 * return an error to the user, because the event is not
+		 * initiated by a user request.
+		 * The best the driver could do is to log an error message.
+		 * We will do it ourselves instead...
+		 */
+		printk(KERN_ERR "%s (WE) : Invalid/Unknown Wireless Event (0x%04X)\n",
+		       dev->name, cmd);
+		return;
+	}
+
+	/* Check extra parameters and set extra_len */
+	if (descr->header_type == IW_HEADER_TYPE_POINT) {
+		/* Check if number of token fits within bounds */
+		if (wrqu->data.length > descr->max_tokens) {
+			printk(KERN_ERR "%s (WE) : Wireless Event too big (%d)\n", dev->name, wrqu->data.length);
+			return;
+		}
+		if (wrqu->data.length < descr->min_tokens) {
+			printk(KERN_ERR "%s (WE) : Wireless Event too small (%d)\n", dev->name, wrqu->data.length);
+			return;
+		}
+		/* Calculate extra_len - extra is NULL for restricted events */
+		if (extra != NULL)
+			extra_len = wrqu->data.length * descr->token_size;
+		/* Always at an offset in wrqu */
+		wrqu_off = IW_EV_POINT_OFF;
+	}
+
+	/* Total length of the event */
+	hdr_len = event_type_size[descr->header_type];
+	event_len = hdr_len + extra_len;
+
+	/*
+	 * The problem for 64/32 bit.
+	 *
+	 * On 64-bit, a regular event is laid out as follows:
+	 *      |  0  |  1  |  2  |  3  |  4  |  5  |  6  |  7  |
+	 *      | event.len | event.cmd |     p a d d i n g     |
+	 *      | wrqu data ... (with the correct size)         |
+	 *
+	 * This padding exists because we manipulate event->u,
+	 * and 'event' is not packed.
+	 *
+	 * An iw_point event is laid out like this instead:
+	 *      |  0  |  1  |  2  |  3  |  4  |  5  |  6  |  7  |
+	 *      | event.len | event.cmd |     p a d d i n g     |
+	 *      | iwpnt.len | iwpnt.flg |     p a d d i n g     |
+	 *      | extra data  ...
+	 *
+	 * The second padding exists because struct iw_point is extended,
+	 * but this depends on the platform...
+	 *
+	 * On 32-bit, all the padding shouldn't be there.
+	 */
+
+	skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
+	if (!skb)
+		return;
+
+	/* Send via the RtNetlink event channel */
+	nlh = rtnetlink_ifinfo_prep(dev, skb);
+	if (WARN_ON(!nlh)) {
+		kfree_skb(skb);
+		return;
+	}
+
+	/* Add the wireless events in the netlink packet */
+	nla = nla_reserve(skb, IFLA_WIRELESS, event_len);
+	if (!nla) {
+		kfree_skb(skb);
+		return;
+	}
+	event = nla_data(nla);
+
+	/* Fill event - first clear to avoid data leaking */
+	memset(event, 0, hdr_len);
+	event->len = event_len;
+	event->cmd = cmd;
+	memcpy(&event->u, ((char *) wrqu) + wrqu_off, hdr_len - IW_EV_LCP_LEN);
+	if (extra_len)
+		memcpy(((char *) event) + hdr_len, extra, extra_len);
+
+	nlmsg_end(skb, nlh);
+#ifdef CONFIG_COMPAT
+	hdr_len = compat_event_type_size[descr->header_type];
+	event_len = hdr_len + extra_len;
+
+	compskb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
+	if (!compskb) {
+		kfree_skb(skb);
+		return;
+	}
+
+	/* Send via the RtNetlink event channel */
+	nlh = rtnetlink_ifinfo_prep(dev, compskb);
+	if (WARN_ON(!nlh)) {
+		kfree_skb(skb);
+		kfree_skb(compskb);
+		return;
+	}
+
+	/* Add the wireless events in the netlink packet */
+	nla = nla_reserve(compskb, IFLA_WIRELESS, event_len);
+	if (!nla) {
+		kfree_skb(skb);
+		kfree_skb(compskb);
+		return;
+	}
+	compat_event = nla_data(nla);
+
+	compat_event->len = event_len;
+	compat_event->cmd = cmd;
+	if (descr->header_type == IW_HEADER_TYPE_POINT) {
+		compat_wrqu.length = wrqu->data.length;
+		compat_wrqu.flags = wrqu->data.flags;
+		memcpy(&compat_event->pointer,
+			((char *) &compat_wrqu) + IW_EV_COMPAT_POINT_OFF,
+			hdr_len - IW_EV_COMPAT_LCP_LEN);
+		if (extra_len)
+			memcpy(((char *) compat_event) + hdr_len,
+				extra, extra_len);
+	} else {
+		/* extra_len must be zero, so no if (extra) needed */
+		memcpy(&compat_event->pointer, wrqu,
+			hdr_len - IW_EV_COMPAT_LCP_LEN);
+	}
+
+	nlmsg_end(compskb, nlh);
+
+	skb_shinfo(skb)->frag_list = compskb;
+#endif
+	skb_queue_tail(&dev_net(dev)->wext_nlevents, skb);
+	schedule_work(&wireless_nlevent_work);
+}
+EXPORT_SYMBOL(wireless_send_event);
+
+
+
+/* IW handlers */
+
+struct iw_statistics *get_wireless_stats(struct net_device *dev)
+{
+#ifdef CONFIG_WIRELESS_EXT
+	if ((dev->wireless_handlers != NULL) &&
+	   (dev->wireless_handlers->get_wireless_stats != NULL))
+		return dev->wireless_handlers->get_wireless_stats(dev);
+#endif
+
+#ifdef CONFIG_CFG80211_WEXT
+	if (dev->ieee80211_ptr && dev->ieee80211_ptr &&
+	    dev->ieee80211_ptr->wiphy &&
+	    dev->ieee80211_ptr->wiphy->wext &&
+	    dev->ieee80211_ptr->wiphy->wext->get_wireless_stats)
+		return dev->ieee80211_ptr->wiphy->wext->get_wireless_stats(dev);
+#endif
+
+	/* not found */
+	return NULL;
+}
+
+static int iw_handler_get_iwstats(struct net_device *		dev,
+				  struct iw_request_info *	info,
+				  union iwreq_data *		wrqu,
+				  char *			extra)
+{
+	/* Get stats from the driver */
+	struct iw_statistics *stats;
+
+	stats = get_wireless_stats(dev);
+	if (stats) {
+		/* Copy statistics to extra */
+		memcpy(extra, stats, sizeof(struct iw_statistics));
+		wrqu->data.length = sizeof(struct iw_statistics);
+
+		/* Check if we need to clear the updated flag */
+		if (wrqu->data.flags != 0)
+			stats->qual.updated &= ~IW_QUAL_ALL_UPDATED;
+		return 0;
+	} else
+		return -EOPNOTSUPP;
+}
+
+static iw_handler get_handler(struct net_device *dev, unsigned int cmd)
+{
+	/* Don't "optimise" the following variable, it will crash */
+	unsigned int	index;		/* *MUST* be unsigned */
+	const struct iw_handler_def *handlers = NULL;
+
+#ifdef CONFIG_CFG80211_WEXT
+	if (dev->ieee80211_ptr && dev->ieee80211_ptr->wiphy)
+		handlers = dev->ieee80211_ptr->wiphy->wext;
+#endif
+#ifdef CONFIG_WIRELESS_EXT
+	if (dev->wireless_handlers)
+		handlers = dev->wireless_handlers;
+#endif
+
+	if (!handlers)
+		return NULL;
+
+	/* Try as a standard command */
+	index = cmd - SIOCIWFIRST;
+	if (index < handlers->num_standard)
+		return handlers->standard[index];
+
+#ifdef CONFIG_WEXT_PRIV
+	/* Try as a private command */
+	index = cmd - SIOCIWFIRSTPRIV;
+	if (index < handlers->num_private)
+		return handlers->private[index];
+#endif
+
+	/* Not found */
+	return NULL;
+}
+
+static int ioctl_standard_iw_point(struct iw_point *iwp, unsigned int cmd,
+				   const struct iw_ioctl_description *descr,
+				   iw_handler handler, struct net_device *dev,
+				   struct iw_request_info *info)
+{
+	int err, extra_size, user_length = 0, essid_compat = 0;
+	char *extra;
+
+	/* Calculate space needed by arguments. Always allocate
+	 * for max space.
+	 */
+	extra_size = descr->max_tokens * descr->token_size;
+
+	/* Check need for ESSID compatibility for WE < 21 */
+	switch (cmd) {
+	case SIOCSIWESSID:
+	case SIOCGIWESSID:
+	case SIOCSIWNICKN:
+	case SIOCGIWNICKN:
+		if (iwp->length == descr->max_tokens + 1)
+			essid_compat = 1;
+		else if (IW_IS_SET(cmd) && (iwp->length != 0)) {
+			char essid[IW_ESSID_MAX_SIZE + 1];
+			unsigned int len;
+			len = iwp->length * descr->token_size;
+
+			if (len > IW_ESSID_MAX_SIZE)
+				return -EFAULT;
+
+			err = copy_from_user(essid, iwp->pointer, len);
+			if (err)
+				return -EFAULT;
+
+			if (essid[iwp->length - 1] == '\0')
+				essid_compat = 1;
+		}
+		break;
+	default:
+		break;
+	}
+
+	iwp->length -= essid_compat;
+
+	/* Check what user space is giving us */
+	if (IW_IS_SET(cmd)) {
+		/* Check NULL pointer */
+		if (!iwp->pointer && iwp->length != 0)
+			return -EFAULT;
+		/* Check if number of token fits within bounds */
+		if (iwp->length > descr->max_tokens)
+			return -E2BIG;
+		if (iwp->length < descr->min_tokens)
+			return -EINVAL;
+	} else {
+		/* Check NULL pointer */
+		if (!iwp->pointer)
+			return -EFAULT;
+		/* Save user space buffer size for checking */
+		user_length = iwp->length;
+
+		/* Don't check if user_length > max to allow forward
+		 * compatibility. The test user_length < min is
+		 * implied by the test at the end.
+		 */
+
+		/* Support for very large requests */
+		if ((descr->flags & IW_DESCR_FLAG_NOMAX) &&
+		    (user_length > descr->max_tokens)) {
+			/* Allow userspace to GET more than max so
+			 * we can support any size GET requests.
+			 * There is still a limit : -ENOMEM.
+			 */
+			extra_size = user_length * descr->token_size;
+
+			/* Note : user_length is originally a __u16,
+			 * and token_size is controlled by us,
+			 * so extra_size won't get negative and
+			 * won't overflow...
+			 */
+		}
+	}
+
+	/* kzalloc() ensures NULL-termination for essid_compat. */
+	extra = kzalloc(extra_size, GFP_KERNEL);
+	if (!extra)
+		return -ENOMEM;
+
+	/* If it is a SET, get all the extra data in here */
+	if (IW_IS_SET(cmd) && (iwp->length != 0)) {
+		if (copy_from_user(extra, iwp->pointer,
+				   iwp->length *
+				   descr->token_size)) {
+			err = -EFAULT;
+			goto out;
+		}
+
+		if (cmd == SIOCSIWENCODEEXT) {
+			struct iw_encode_ext *ee = (void *) extra;
+
+			if (iwp->length < sizeof(*ee) + ee->key_len)
+				return -EFAULT;
+		}
+	}
+
+	err = handler(dev, info, (union iwreq_data *) iwp, extra);
+
+	iwp->length += essid_compat;
+
+	/* If we have something to return to the user */
+	if (!err && IW_IS_GET(cmd)) {
+		/* Check if there is enough buffer up there */
+		if (user_length < iwp->length) {
+			err = -E2BIG;
+			goto out;
+		}
+
+		if (copy_to_user(iwp->pointer, extra,
+				 iwp->length *
+				 descr->token_size)) {
+			err = -EFAULT;
+			goto out;
+		}
+	}
+
+	/* Generate an event to notify listeners of the change */
+	if ((descr->flags & IW_DESCR_FLAG_EVENT) && err == -EIWCOMMIT) {
+		union iwreq_data *data = (union iwreq_data *) iwp;
+
+		if (descr->flags & IW_DESCR_FLAG_RESTRICT)
+			/* If the event is restricted, don't
+			 * export the payload.
+			 */
+			wireless_send_event(dev, cmd, data, NULL);
+		else
+			wireless_send_event(dev, cmd, data, extra);
+	}
+
+out:
+	kfree(extra);
+	return err;
+}
+
+/*
+ * 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()" ;-)
+ */
+int call_commit_handler(struct net_device *dev)
+{
+#ifdef CONFIG_WIRELESS_EXT
+	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 */
+#else
+	/* cfg80211 has no commit */
+	return 0;
+#endif
+}
+
+/*
+ * Main IOCTl dispatcher.
+ * Check the type of IOCTL and call the appropriate wrapper...
+ */
+static int wireless_process_ioctl(struct net *net, struct ifreq *ifr,
+				  unsigned int cmd,
+				  struct iw_request_info *info,
+				  wext_ioctl_func standard,
+				  wext_ioctl_func private)
+{
+	struct iwreq *iwr = (struct iwreq *) ifr;
+	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(net, 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) */
+	if (cmd == SIOCGIWSTATS)
+		return standard(dev, iwr, cmd, info,
+				&iw_handler_get_iwstats);
+
+#ifdef CONFIG_WEXT_PRIV
+	if (cmd == SIOCGIWPRIV && dev->wireless_handlers)
+		return standard(dev, iwr, cmd, info,
+				iw_handler_get_private);
+#endif
+
+	/* Basic check */
+	if (!netif_device_present(dev))
+		return -ENODEV;
+
+	/* New driver API : try to find the handler */
+	handler = get_handler(dev, cmd);
+	if (handler) {
+		/* Standard and private are not the same */
+		if (cmd < SIOCIWFIRSTPRIV)
+			return standard(dev, iwr, cmd, info, handler);
+		else if (private)
+			return private(dev, iwr, cmd, info, handler);
+	}
+	/* Old driver API : call driver ioctl handler */
+	if (dev->netdev_ops->ndo_do_ioctl)
+		return dev->netdev_ops->ndo_do_ioctl(dev, ifr, cmd);
+	return -EOPNOTSUPP;
+}
+
+/* If command is `set a parameter', or `get the encoding parameters',
+ * check if the user has the right to do it.
+ */
+static int wext_permission_check(unsigned int cmd)
+{
+	if ((IW_IS_SET(cmd) || cmd == SIOCGIWENCODE || cmd == SIOCGIWENCODEEXT)
+	    && !capable(CAP_NET_ADMIN))
+		return -EPERM;
+
+	return 0;
+}
+
+/* entry point from dev ioctl */
+static int wext_ioctl_dispatch(struct net *net, struct ifreq *ifr,
+			       unsigned int cmd, struct iw_request_info *info,
+			       wext_ioctl_func standard,
+			       wext_ioctl_func private)
+{
+	int ret = wext_permission_check(cmd);
+
+	if (ret)
+		return ret;
+
+	dev_load(net, ifr->ifr_name);
+	rtnl_lock();
+	ret = wireless_process_ioctl(net, ifr, cmd, info, standard, private);
+	rtnl_unlock();
+
+	return ret;
+}
+
+/*
+ * 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 int ioctl_standard_call(struct net_device *	dev,
+			       struct iwreq		*iwr,
+			       unsigned int		cmd,
+			       struct iw_request_info	*info,
+			       iw_handler		handler)
+{
+	const struct iw_ioctl_description *	descr;
+	int					ret = -EINVAL;
+
+	/* Get the description of the IOCTL */
+	if ((cmd - SIOCIWFIRST) >= standard_ioctl_num)
+		return -EOPNOTSUPP;
+	descr = &(standard_ioctl[cmd - SIOCIWFIRST]);
+
+	/* 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);
+
+		/* 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);
+	} else {
+		ret = ioctl_standard_iw_point(&iwr->u.data, cmd, descr,
+					      handler, dev, info);
+	}
+
+	/* 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;
+}
+
+
+int wext_handle_ioctl(struct net *net, struct ifreq *ifr, unsigned int cmd,
+		      void __user *arg)
+{
+	struct iw_request_info info = { .cmd = cmd, .flags = 0 };
+	int ret;
+
+	ret = wext_ioctl_dispatch(net, ifr, cmd, &info,
+				  ioctl_standard_call,
+				  ioctl_private_call);
+	if (ret >= 0 &&
+	    IW_IS_GET(cmd) &&
+	    copy_to_user(arg, ifr, sizeof(struct iwreq)))
+		return -EFAULT;
+
+	return ret;
+}
+
+#ifdef CONFIG_COMPAT
+static int compat_standard_call(struct net_device	*dev,
+				struct iwreq		*iwr,
+				unsigned int		cmd,
+				struct iw_request_info	*info,
+				iw_handler		handler)
+{
+	const struct iw_ioctl_description *descr;
+	struct compat_iw_point *iwp_compat;
+	struct iw_point iwp;
+	int err;
+
+	descr = standard_ioctl + (cmd - SIOCIWFIRST);
+
+	if (descr->header_type != IW_HEADER_TYPE_POINT)
+		return ioctl_standard_call(dev, iwr, cmd, info, handler);
+
+	iwp_compat = (struct compat_iw_point *) &iwr->u.data;
+	iwp.pointer = compat_ptr(iwp_compat->pointer);
+	iwp.length = iwp_compat->length;
+	iwp.flags = iwp_compat->flags;
+
+	err = ioctl_standard_iw_point(&iwp, cmd, descr, handler, dev, info);
+
+	iwp_compat->pointer = ptr_to_compat(iwp.pointer);
+	iwp_compat->length = iwp.length;
+	iwp_compat->flags = iwp.flags;
+
+	return err;
+}
+
+int compat_wext_handle_ioctl(struct net *net, unsigned int cmd,
+			     unsigned long arg)
+{
+	void __user *argp = (void __user *)arg;
+	struct iw_request_info info;
+	struct iwreq iwr;
+	char *colon;
+	int ret;
+
+	if (copy_from_user(&iwr, argp, sizeof(struct iwreq)))
+		return -EFAULT;
+
+	iwr.ifr_name[IFNAMSIZ-1] = 0;
+	colon = strchr(iwr.ifr_name, ':');
+	if (colon)
+		*colon = 0;
+
+	info.cmd = cmd;
+	info.flags = IW_REQUEST_FLAG_COMPAT;
+
+	ret = wext_ioctl_dispatch(net, (struct ifreq *) &iwr, cmd, &info,
+				  compat_standard_call,
+				  compat_private_call);
+
+	if (ret >= 0 &&
+	    IW_IS_GET(cmd) &&
+	    copy_to_user(argp, &iwr, sizeof(struct iwreq)))
+		return -EFAULT;
+
+	return ret;
+}
+#endif