1 | /* |
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 <linux/export.h> |
14 | #include <net/iw_handler.h> |
15 | #include <net/arp.h> |
16 | #include <net/wext.h> |
17 | |
18 | static inline struct iw_spy_data *get_spydata(struct net_device *dev) |
19 | { |
20 | /* This is the new way */ |
21 | if (dev->wireless_data) |
22 | return dev->wireless_data->spy_data; |
23 | return NULL; |
24 | } |
25 | |
26 | int iw_handler_set_spy(struct net_device * dev, |
27 | struct iw_request_info * info, |
28 | union iwreq_data * wrqu, |
29 | char * ) |
30 | { |
31 | struct iw_spy_data * spydata = get_spydata(dev); |
32 | struct sockaddr * address = (struct sockaddr *) extra; |
33 | |
34 | /* Make sure driver is not buggy or using the old API */ |
35 | if (!spydata) |
36 | return -EOPNOTSUPP; |
37 | |
38 | /* Disable spy collection while we copy the addresses. |
39 | * While we copy addresses, any call to wireless_spy_update() |
40 | * will NOP. This is OK, as anyway the addresses are changing. */ |
41 | spydata->spy_number = 0; |
42 | |
43 | /* We want to operate without locking, because wireless_spy_update() |
44 | * most likely will happen in the interrupt handler, and therefore |
45 | * have its own locking constraints and needs performance. |
46 | * The rtnl_lock() make sure we don't race with the other iw_handlers. |
47 | * This make sure wireless_spy_update() "see" that the spy list |
48 | * is temporarily disabled. */ |
49 | smp_wmb(); |
50 | |
51 | /* Are there are addresses to copy? */ |
52 | if (wrqu->data.length > 0) { |
53 | int i; |
54 | |
55 | /* Copy addresses */ |
56 | for (i = 0; i < wrqu->data.length; i++) |
57 | memcpy(spydata->spy_address[i], address[i].sa_data, |
58 | ETH_ALEN); |
59 | /* Reset stats */ |
60 | memset(spydata->spy_stat, 0, |
61 | sizeof(struct iw_quality) * IW_MAX_SPY); |
62 | } |
63 | |
64 | /* Make sure above is updated before re-enabling */ |
65 | smp_wmb(); |
66 | |
67 | /* Enable addresses */ |
68 | spydata->spy_number = wrqu->data.length; |
69 | |
70 | return 0; |
71 | } |
72 | EXPORT_SYMBOL(iw_handler_set_spy); |
73 | |
74 | int iw_handler_get_spy(struct net_device * dev, |
75 | struct iw_request_info * info, |
76 | union iwreq_data * wrqu, |
77 | char * ) |
78 | { |
79 | struct iw_spy_data * spydata = get_spydata(dev); |
80 | struct sockaddr * address = (struct sockaddr *) extra; |
81 | int i; |
82 | |
83 | /* Make sure driver is not buggy or using the old API */ |
84 | if (!spydata) |
85 | return -EOPNOTSUPP; |
86 | |
87 | wrqu->data.length = spydata->spy_number; |
88 | |
89 | /* Copy addresses. */ |
90 | for (i = 0; i < spydata->spy_number; i++) { |
91 | memcpy(address[i].sa_data, spydata->spy_address[i], ETH_ALEN); |
92 | address[i].sa_family = AF_UNIX; |
93 | } |
94 | /* Copy stats to the user buffer (just after). */ |
95 | if (spydata->spy_number > 0) |
96 | memcpy(extra + (sizeof(struct sockaddr) *spydata->spy_number), |
97 | spydata->spy_stat, |
98 | sizeof(struct iw_quality) * spydata->spy_number); |
99 | /* Reset updated flags. */ |
100 | for (i = 0; i < spydata->spy_number; i++) |
101 | spydata->spy_stat[i].updated &= ~IW_QUAL_ALL_UPDATED; |
102 | return 0; |
103 | } |
104 | EXPORT_SYMBOL(iw_handler_get_spy); |
105 | |
106 | /*------------------------------------------------------------------*/ |
107 | /* |
108 | * Standard Wireless Handler : set spy threshold |
109 | */ |
110 | int iw_handler_set_thrspy(struct net_device * dev, |
111 | struct iw_request_info *info, |
112 | union iwreq_data * wrqu, |
113 | char * ) |
114 | { |
115 | struct iw_spy_data * spydata = get_spydata(dev); |
116 | struct iw_thrspy * threshold = (struct iw_thrspy *) extra; |
117 | |
118 | /* Make sure driver is not buggy or using the old API */ |
119 | if (!spydata) |
120 | return -EOPNOTSUPP; |
121 | |
122 | /* Just do it */ |
123 | spydata->spy_thr_low = threshold->low; |
124 | spydata->spy_thr_high = threshold->high; |
125 | |
126 | /* Clear flag */ |
127 | memset(spydata->spy_thr_under, '\0', sizeof(spydata->spy_thr_under)); |
128 | |
129 | return 0; |
130 | } |
131 | EXPORT_SYMBOL(iw_handler_set_thrspy); |
132 | |
133 | /*------------------------------------------------------------------*/ |
134 | /* |
135 | * Standard Wireless Handler : get spy threshold |
136 | */ |
137 | int iw_handler_get_thrspy(struct net_device * dev, |
138 | struct iw_request_info *info, |
139 | union iwreq_data * wrqu, |
140 | char * ) |
141 | { |
142 | struct iw_spy_data * spydata = get_spydata(dev); |
143 | struct iw_thrspy * threshold = (struct iw_thrspy *) extra; |
144 | |
145 | /* Make sure driver is not buggy or using the old API */ |
146 | if (!spydata) |
147 | return -EOPNOTSUPP; |
148 | |
149 | /* Just do it */ |
150 | threshold->low = spydata->spy_thr_low; |
151 | threshold->high = spydata->spy_thr_high; |
152 | |
153 | return 0; |
154 | } |
155 | EXPORT_SYMBOL(iw_handler_get_thrspy); |
156 | |
157 | /*------------------------------------------------------------------*/ |
158 | /* |
159 | * Prepare and send a Spy Threshold event |
160 | */ |
161 | static void iw_send_thrspy_event(struct net_device * dev, |
162 | struct iw_spy_data * spydata, |
163 | unsigned char * address, |
164 | struct iw_quality * wstats) |
165 | { |
166 | union iwreq_data wrqu; |
167 | struct iw_thrspy threshold; |
168 | |
169 | /* Init */ |
170 | wrqu.data.length = 1; |
171 | wrqu.data.flags = 0; |
172 | /* Copy address */ |
173 | memcpy(threshold.addr.sa_data, address, ETH_ALEN); |
174 | threshold.addr.sa_family = ARPHRD_ETHER; |
175 | /* Copy stats */ |
176 | threshold.qual = *wstats; |
177 | /* Copy also thresholds */ |
178 | threshold.low = spydata->spy_thr_low; |
179 | threshold.high = spydata->spy_thr_high; |
180 | |
181 | /* Send event to user space */ |
182 | wireless_send_event(dev, SIOCGIWTHRSPY, wrqu: &wrqu, extra: (char *) &threshold); |
183 | } |
184 | |
185 | /* ---------------------------------------------------------------- */ |
186 | /* |
187 | * Call for the driver to update the spy data. |
188 | * For now, the spy data is a simple array. As the size of the array is |
189 | * small, this is good enough. If we wanted to support larger number of |
190 | * spy addresses, we should use something more efficient... |
191 | */ |
192 | void wireless_spy_update(struct net_device * dev, |
193 | unsigned char * address, |
194 | struct iw_quality * wstats) |
195 | { |
196 | struct iw_spy_data * spydata = get_spydata(dev); |
197 | int i; |
198 | int match = -1; |
199 | |
200 | /* Make sure driver is not buggy or using the old API */ |
201 | if (!spydata) |
202 | return; |
203 | |
204 | /* Update all records that match */ |
205 | for (i = 0; i < spydata->spy_number; i++) |
206 | if (ether_addr_equal(addr1: address, addr2: spydata->spy_address[i])) { |
207 | memcpy(&(spydata->spy_stat[i]), wstats, |
208 | sizeof(struct iw_quality)); |
209 | match = i; |
210 | } |
211 | |
212 | /* Generate an event if we cross the spy threshold. |
213 | * To avoid event storms, we have a simple hysteresis : we generate |
214 | * event only when we go under the low threshold or above the |
215 | * high threshold. */ |
216 | if (match >= 0) { |
217 | if (spydata->spy_thr_under[match]) { |
218 | if (wstats->level > spydata->spy_thr_high.level) { |
219 | spydata->spy_thr_under[match] = 0; |
220 | iw_send_thrspy_event(dev, spydata, |
221 | address, wstats); |
222 | } |
223 | } else { |
224 | if (wstats->level < spydata->spy_thr_low.level) { |
225 | spydata->spy_thr_under[match] = 1; |
226 | iw_send_thrspy_event(dev, spydata, |
227 | address, wstats); |
228 | } |
229 | } |
230 | } |
231 | } |
232 | EXPORT_SYMBOL(wireless_spy_update); |
233 | |