[linux.git] / net / wireless / wext-spy.c

/*
 * This file implement the Wireless Extensions spy API.
 *
 * Authors :	Jean Tourrilhes - HPL - <[email protected]>
 * Copyright (c) 1997-2007 Jean Tourrilhes, All Rights Reserved.
 *
 * (As all part of the Linux kernel, this file is GPL)
 */

#include <linux/wireless.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <net/iw_handler.h>
#include <net/arp.h>
#include <net/wext.h>

static inline struct iw_spy_data *get_spydata(struct net_device *dev)
{
	/* This is the new way */
	if (dev->wireless_data)
		return dev->wireless_data->spy_data;
	return NULL;
}

int iw_handler_set_spy(struct net_device *	dev,
		       struct iw_request_info *	info,
		       union iwreq_data *	wrqu,
		       char *			extra)
{
	struct iw_spy_data *	spydata = get_spydata(dev);
	struct sockaddr *	address = (struct sockaddr *) extra;

	/* Make sure driver is not buggy or using the old API */
	if (!spydata)
		return -EOPNOTSUPP;

	/* Disable spy collection while we copy the addresses.
	 * While we copy addresses, any call to wireless_spy_update()
	 * will NOP. This is OK, as anyway the addresses are changing. */
	spydata->spy_number = 0;

	/* We want to operate without locking, because wireless_spy_update()
	 * most likely will happen in the interrupt handler, and therefore
	 * have its own locking constraints and needs performance.
	 * The rtnl_lock() make sure we don't race with the other iw_handlers.
	 * This make sure wireless_spy_update() "see" that the spy list
	 * is temporarily disabled. */
	smp_wmb();

	/* Are there are addresses to copy? */
	if (wrqu->data.length > 0) {
		int i;

		/* Copy addresses */
		for (i = 0; i < wrqu->data.length; i++)
			memcpy(spydata->spy_address[i], address[i].sa_data,
			       ETH_ALEN);
		/* Reset stats */
		memset(spydata->spy_stat, 0,
		       sizeof(struct iw_quality) * IW_MAX_SPY);
	}

	/* Make sure above is updated before re-enabling */
	smp_wmb();

	/* Enable addresses */
	spydata->spy_number = wrqu->data.length;

	return 0;
}
EXPORT_SYMBOL(iw_handler_set_spy);

int iw_handler_get_spy(struct net_device *	dev,
		       struct iw_request_info *	info,
		       union iwreq_data *	wrqu,
		       char *			extra)
{
	struct iw_spy_data *	spydata = get_spydata(dev);
	struct sockaddr *	address = (struct sockaddr *) extra;
	int			i;

	/* Make sure driver is not buggy or using the old API */
	if (!spydata)
		return -EOPNOTSUPP;

	wrqu->data.length = spydata->spy_number;

	/* Copy addresses. */
	for (i = 0; i < spydata->spy_number; i++) 	{
		memcpy(address[i].sa_data, spydata->spy_address[i], ETH_ALEN);
		address[i].sa_family = AF_UNIX;
	}
	/* Copy stats to the user buffer (just after). */
	if (spydata->spy_number > 0)
		memcpy(extra  + (sizeof(struct sockaddr) *spydata->spy_number),
		       spydata->spy_stat,
		       sizeof(struct iw_quality) * spydata->spy_number);
	/* Reset updated flags. */
	for (i = 0; i < spydata->spy_number; i++)
		spydata->spy_stat[i].updated &= ~IW_QUAL_ALL_UPDATED;
	return 0;
}
EXPORT_SYMBOL(iw_handler_get_spy);

/*------------------------------------------------------------------*/
/*
 * Standard Wireless Handler : set spy threshold
 */
int iw_handler_set_thrspy(struct net_device *	dev,
			  struct iw_request_info *info,
			  union iwreq_data *	wrqu,
			  char *		extra)
{
	struct iw_spy_data *	spydata = get_spydata(dev);
	struct iw_thrspy *	threshold = (struct iw_thrspy *) extra;

	/* Make sure driver is not buggy or using the old API */
	if (!spydata)
		return -EOPNOTSUPP;

	/* Just do it */
	memcpy(&(spydata->spy_thr_low), &(threshold->low),
	       2 * sizeof(struct iw_quality));

	/* Clear flag */
	memset(spydata->spy_thr_under, '\0', sizeof(spydata->spy_thr_under));

	return 0;
}
EXPORT_SYMBOL(iw_handler_set_thrspy);

/*------------------------------------------------------------------*/
/*
 * Standard Wireless Handler : get spy threshold
 */
int iw_handler_get_thrspy(struct net_device *	dev,
			  struct iw_request_info *info,
			  union iwreq_data *	wrqu,
			  char *		extra)
{
	struct iw_spy_data *	spydata = get_spydata(dev);
	struct iw_thrspy *	threshold = (struct iw_thrspy *) extra;

	/* Make sure driver is not buggy or using the old API */
	if (!spydata)
		return -EOPNOTSUPP;

	/* Just do it */
	memcpy(&(threshold->low), &(spydata->spy_thr_low),
	       2 * sizeof(struct iw_quality));

	return 0;
}
EXPORT_SYMBOL(iw_handler_get_thrspy);

/*------------------------------------------------------------------*/
/*
 * Prepare and send a Spy Threshold event
 */
static void iw_send_thrspy_event(struct net_device *	dev,
				 struct iw_spy_data *	spydata,
				 unsigned char *	address,
				 struct iw_quality *	wstats)
{
	union iwreq_data	wrqu;
	struct iw_thrspy	threshold;

	/* Init */
	wrqu.data.length = 1;
	wrqu.data.flags = 0;
	/* Copy address */
	memcpy(threshold.addr.sa_data, address, ETH_ALEN);
	threshold.addr.sa_family = ARPHRD_ETHER;
	/* Copy stats */
	memcpy(&(threshold.qual), wstats, sizeof(struct iw_quality));
	/* Copy also thresholds */
	memcpy(&(threshold.low), &(spydata->spy_thr_low),
	       2 * sizeof(struct iw_quality));

	/* Send event to user space */
	wireless_send_event(dev, SIOCGIWTHRSPY, &wrqu, (char *) &threshold);
}

/* ---------------------------------------------------------------- */
/*
 * Call for the driver to update the spy data.
 * For now, the spy data is a simple array. As the size of the array is
 * small, this is good enough. If we wanted to support larger number of
 * spy addresses, we should use something more efficient...
 */
void wireless_spy_update(struct net_device *	dev,
			 unsigned char *	address,
			 struct iw_quality *	wstats)
{
	struct iw_spy_data *	spydata = get_spydata(dev);
	int			i;
	int			match = -1;

	/* Make sure driver is not buggy or using the old API */
	if (!spydata)
		return;

	/* Update all records that match */
	for (i = 0; i < spydata->spy_number; i++)
		if (!compare_ether_addr(address, spydata->spy_address[i])) {
			memcpy(&(spydata->spy_stat[i]), wstats,
			       sizeof(struct iw_quality));
			match = i;
		}

	/* Generate an event if we cross the spy threshold.
	 * To avoid event storms, we have a simple hysteresis : we generate
	 * event only when we go under the low threshold or above the
	 * high threshold. */
	if (match >= 0) {
		if (spydata->spy_thr_under[match]) {
			if (wstats->level > spydata->spy_thr_high.level) {
				spydata->spy_thr_under[match] = 0;
				iw_send_thrspy_event(dev, spydata,
						     address, wstats);
			}
		} else {
			if (wstats->level < spydata->spy_thr_low.level) {
				spydata->spy_thr_under[match] = 1;
				iw_send_thrspy_event(dev, spydata,
						     address, wstats);
			}
		}
	}
}
EXPORT_SYMBOL(wireless_spy_update);
Commit	Line	Data
3d23e349 JB	1	/*
	2	* This file implement the Wireless Extensions spy API.
	3	*
	4	* Authors : Jean Tourrilhes - HPL - <[email protected]>
	5	* Copyright (c) 1997-2007 Jean Tourrilhes, All Rights Reserved.
	6	*
	7	* (As all part of the Linux kernel, this file is GPL)
	8	*/
	9
	10	#include <linux/wireless.h>
	11	#include <linux/netdevice.h>
	12	#include <linux/etherdevice.h>
	13	#include <net/iw_handler.h>
	14	#include <net/arp.h>
	15	#include <net/wext.h>
	16
	17	static inline struct iw_spy_data get_spydata(struct net_device dev)
	18	{
	19	/* This is the new way */
	20	if (dev->wireless_data)
	21	return dev->wireless_data->spy_data;
	22	return NULL;
	23	}
	24
	25	int iw_handler_set_spy(struct net_device * dev,
	26	struct iw_request_info * info,
	27	union iwreq_data * wrqu,
	28	char * extra)
	29	{
	30	struct iw_spy_data * spydata = get_spydata(dev);
	31	struct sockaddr * address = (struct sockaddr *) extra;
	32
	33	/* Make sure driver is not buggy or using the old API */
	34	if (!spydata)
	35	return -EOPNOTSUPP;
	36
	37	/* Disable spy collection while we copy the addresses.
	38	* While we copy addresses, any call to wireless_spy_update()
	39	* will NOP. This is OK, as anyway the addresses are changing. */
	40	spydata->spy_number = 0;
	41
	42	/* We want to operate without locking, because wireless_spy_update()
	43	* most likely will happen in the interrupt handler, and therefore
	44	* have its own locking constraints and needs performance.
	45	* The rtnl_lock() make sure we don't race with the other iw_handlers.
	46	* This make sure wireless_spy_update() "see" that the spy list
	47	* is temporarily disabled. */
	48	smp_wmb();
	49
	50	/* Are there are addresses to copy? */
	51	if (wrqu->data.length > 0) {
	52	int i;
	53
	54	/* Copy addresses */
	55	for (i = 0; i < wrqu->data.length; i++)
	56	memcpy(spydata->spy_address[i], address[i].sa_data,
	57	ETH_ALEN);
	58	/* Reset stats */
	59	memset(spydata->spy_stat, 0,
	60	sizeof(struct iw_quality) * IW_MAX_SPY);
	61	}
	62
	63	/* Make sure above is updated before re-enabling */
	64	smp_wmb();
65
66	/* Enable addresses */
67	spydata->spy_number = wrqu->data.length;
68
69	return 0;
70	}
71	EXPORT_SYMBOL(iw_handler_set_spy);
72
73	int iw_handler_get_spy(struct net_device * dev,
74	struct iw_request_info * info,
75	union iwreq_data * wrqu,
76	char * extra)
77	{
78	struct iw_spy_data * spydata = get_spydata(dev);
79	struct sockaddr * address = (struct sockaddr *) extra;
80	int i;
81
82	/* Make sure driver is not buggy or using the old API */
83	if (!spydata)
84	return -EOPNOTSUPP;
85
86	wrqu->data.length = spydata->spy_number;
87
88	/* Copy addresses. */
89	for (i = 0; i < spydata->spy_number; i++) {
90	memcpy(address[i].sa_data, spydata->spy_address[i], ETH_ALEN);
91	address[i].sa_family = AF_UNIX;
92	}
93	/* Copy stats to the user buffer (just after). */
94	if (spydata->spy_number > 0)
95	memcpy(extra + (sizeof(struct sockaddr) *spydata->spy_number),
96	spydata->spy_stat,
97	sizeof(struct iw_quality) * spydata->spy_number);
98	/* Reset updated flags. */
99	for (i = 0; i < spydata->spy_number; i++)
100	spydata->spy_stat[i].updated &= ~IW_QUAL_ALL_UPDATED;
101	return 0;
102	}
103	EXPORT_SYMBOL(iw_handler_get_spy);
104
105	/------------------------------------------------------------------/
106	/*
107	* Standard Wireless Handler : set spy threshold
108	*/
109	int iw_handler_set_thrspy(struct net_device * dev,
110	struct iw_request_info *info,
111	union iwreq_data * wrqu,
112	char * extra)
113	{
114	struct iw_spy_data * spydata = get_spydata(dev);
115	struct iw_thrspy * threshold = (struct iw_thrspy *) extra;
116
117	/* Make sure driver is not buggy or using the old API */
118	if (!spydata)
119	return -EOPNOTSUPP;
120
121	/* Just do it */
122	memcpy(&(spydata->spy_thr_low), &(threshold->low),
123	2 * sizeof(struct iw_quality));
124
125	/* Clear flag */
126	memset(spydata->spy_thr_under, '\0', sizeof(spydata->spy_thr_under));
127
128	return 0;
129	}
130	EXPORT_SYMBOL(iw_handler_set_thrspy);
131
132	/------------------------------------------------------------------/
133	/*
134	* Standard Wireless Handler : get spy threshold
135	*/
136	int iw_handler_get_thrspy(struct net_device * dev,
137	struct iw_request_info *info,
138	union iwreq_data * wrqu,
139	char * extra)
140	{
141	struct iw_spy_data * spydata = get_spydata(dev);
142	struct iw_thrspy * threshold = (struct iw_thrspy *) extra;
143
144	/* Make sure driver is not buggy or using the old API */
145	if (!spydata)
146	return -EOPNOTSUPP;
147
148	/* Just do it */
149	memcpy(&(threshold->low), &(spydata->spy_thr_low),
150	2 * sizeof(struct iw_quality));
151
152	return 0;
153	}
154	EXPORT_SYMBOL(iw_handler_get_thrspy);
155
156	/------------------------------------------------------------------/
157	/*
158	* Prepare and send a Spy Threshold event
159	*/
160	static void iw_send_thrspy_event(struct net_device * dev,
161	struct iw_spy_data * spydata,
162	unsigned char * address,
163	struct iw_quality * wstats)
164	{
165	union iwreq_data wrqu;
166	struct iw_thrspy threshold;
167
168	/* Init */
169	wrqu.data.length = 1;
170	wrqu.data.flags = 0;
171	/* Copy address */
172	memcpy(threshold.addr.sa_data, address, ETH_ALEN);
173	threshold.addr.sa_family = ARPHRD_ETHER;
174	/* Copy stats */
175	memcpy(&(threshold.qual), wstats, sizeof(struct iw_quality));
176	/* Copy also thresholds */
177	memcpy(&(threshold.low), &(spydata->spy_thr_low),
178	2 * sizeof(struct iw_quality));
179
180	/* Send event to user space */
181	wireless_send_event(dev, SIOCGIWTHRSPY, &wrqu, (char *) &threshold);
182	}
183
184	/* ---------------------------------------------------------------- */
185	/*
186	* Call for the driver to update the spy data.
187	* For now, the spy data is a simple array. As the size of the array is
188	* small, this is good enough. If we wanted to support larger number of
189	* spy addresses, we should use something more efficient...
190	*/
191	void wireless_spy_update(struct net_device * dev,
192	unsigned char * address,
193	struct iw_quality * wstats)
194	{
195	struct iw_spy_data * spydata = get_spydata(dev);
196	int i;
197	int match = -1;
198
199	/* Make sure driver is not buggy or using the old API */
200	if (!spydata)
201	return;
202
203	/* Update all records that match */
204	for (i = 0; i < spydata->spy_number; i++)
205	if (!compare_ether_addr(address, spydata->spy_address[i])) {
206	memcpy(&(spydata->spy_stat[i]), wstats,
207	sizeof(struct iw_quality));
208	match = i;
209	}
210
211	/* Generate an event if we cross the spy threshold.
212	* To avoid event storms, we have a simple hysteresis : we generate
213	* event only when we go under the low threshold or above the
214	* high threshold. */
215	if (match >= 0) {
216	if (spydata->spy_thr_under[match]) {
217	if (wstats->level > spydata->spy_thr_high.level) {
218	spydata->spy_thr_under[match] = 0;
219	iw_send_thrspy_event(dev, spydata,
220	address, wstats);
221	}
222	} else {
223	if (wstats->level < spydata->spy_thr_low.level) {
224	spydata->spy_thr_under[match] = 1;
225	iw_send_thrspy_event(dev, spydata,
226	address, wstats);
227	}
228	}
229	}
230	}
231	EXPORT_SYMBOL(wireless_spy_update);