blob: 6dcfe65a2d1ad0d69958d40959a4121c05a6a8cf [file] [log] [blame]
Johannes Berg3d23e342009-09-29 23:27:28 +02001/*
2 * This file implement the Wireless Extensions spy API.
3 *
4 * Authors : Jean Tourrilhes - HPL - <jt@hpl.hp.com>
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
17static 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
25int 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}
71EXPORT_SYMBOL(iw_handler_set_spy);
72
73int 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}
103EXPORT_SYMBOL(iw_handler_get_spy);
104
105/*------------------------------------------------------------------*/
106/*
107 * Standard Wireless Handler : set spy threshold
108 */
109int 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}
130EXPORT_SYMBOL(iw_handler_set_thrspy);
131
132/*------------------------------------------------------------------*/
133/*
134 * Standard Wireless Handler : get spy threshold
135 */
136int 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}
154EXPORT_SYMBOL(iw_handler_get_thrspy);
155
156/*------------------------------------------------------------------*/
157/*
158 * Prepare and send a Spy Threshold event
159 */
160static 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 */
191void 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}
231EXPORT_SYMBOL(wireless_spy_update);