diff options
author | David S. Miller <davem@davemloft.net> | 2010-02-14 20:45:59 -0500 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2010-02-14 20:45:59 -0500 |
commit | f6f223039c0d0683bdea1eabd35b309e10311a60 (patch) | |
tree | 890e07acf8c18ddc2994ebc0a0bdcdda38b0dcc6 /net/wireless | |
parent | b3b3f04fb587ecb61b5baa6c1c5f0e666fd12d73 (diff) | |
parent | 42c4568a4ace0adc27a9d6f02936e2047ba6fc7e (diff) |
Merge branch 'master' of ssh://master.kernel.org/pub/scm/linux/kernel/git/linville/wireless-next-2.6
Diffstat (limited to 'net/wireless')
-rw-r--r-- | net/wireless/radiotap.c | 305 |
1 files changed, 198 insertions, 107 deletions
diff --git a/net/wireless/radiotap.c b/net/wireless/radiotap.c index f591871a7b4f..1332c445d1c7 100644 --- a/net/wireless/radiotap.c +++ b/net/wireless/radiotap.c | |||
@@ -2,6 +2,16 @@ | |||
2 | * Radiotap parser | 2 | * Radiotap parser |
3 | * | 3 | * |
4 | * Copyright 2007 Andy Green <andy@warmcat.com> | 4 | * Copyright 2007 Andy Green <andy@warmcat.com> |
5 | * Copyright 2009 Johannes Berg <johannes@sipsolutions.net> | ||
6 | * | ||
7 | * This program is free software; you can redistribute it and/or modify | ||
8 | * it under the terms of the GNU General Public License version 2 as | ||
9 | * published by the Free Software Foundation. | ||
10 | * | ||
11 | * Alternatively, this software may be distributed under the terms of BSD | ||
12 | * license. | ||
13 | * | ||
14 | * See COPYING for more details. | ||
5 | */ | 15 | */ |
6 | 16 | ||
7 | #include <net/cfg80211.h> | 17 | #include <net/cfg80211.h> |
@@ -10,6 +20,35 @@ | |||
10 | 20 | ||
11 | /* function prototypes and related defs are in include/net/cfg80211.h */ | 21 | /* function prototypes and related defs are in include/net/cfg80211.h */ |
12 | 22 | ||
23 | static const struct radiotap_align_size rtap_namespace_sizes[] = { | ||
24 | [IEEE80211_RADIOTAP_TSFT] = { .align = 8, .size = 8, }, | ||
25 | [IEEE80211_RADIOTAP_FLAGS] = { .align = 1, .size = 1, }, | ||
26 | [IEEE80211_RADIOTAP_RATE] = { .align = 1, .size = 1, }, | ||
27 | [IEEE80211_RADIOTAP_CHANNEL] = { .align = 2, .size = 4, }, | ||
28 | [IEEE80211_RADIOTAP_FHSS] = { .align = 2, .size = 2, }, | ||
29 | [IEEE80211_RADIOTAP_DBM_ANTSIGNAL] = { .align = 1, .size = 1, }, | ||
30 | [IEEE80211_RADIOTAP_DBM_ANTNOISE] = { .align = 1, .size = 1, }, | ||
31 | [IEEE80211_RADIOTAP_LOCK_QUALITY] = { .align = 2, .size = 2, }, | ||
32 | [IEEE80211_RADIOTAP_TX_ATTENUATION] = { .align = 2, .size = 2, }, | ||
33 | [IEEE80211_RADIOTAP_DB_TX_ATTENUATION] = { .align = 2, .size = 2, }, | ||
34 | [IEEE80211_RADIOTAP_DBM_TX_POWER] = { .align = 1, .size = 1, }, | ||
35 | [IEEE80211_RADIOTAP_ANTENNA] = { .align = 1, .size = 1, }, | ||
36 | [IEEE80211_RADIOTAP_DB_ANTSIGNAL] = { .align = 1, .size = 1, }, | ||
37 | [IEEE80211_RADIOTAP_DB_ANTNOISE] = { .align = 1, .size = 1, }, | ||
38 | [IEEE80211_RADIOTAP_RX_FLAGS] = { .align = 2, .size = 2, }, | ||
39 | [IEEE80211_RADIOTAP_TX_FLAGS] = { .align = 2, .size = 2, }, | ||
40 | [IEEE80211_RADIOTAP_RTS_RETRIES] = { .align = 1, .size = 1, }, | ||
41 | [IEEE80211_RADIOTAP_DATA_RETRIES] = { .align = 1, .size = 1, }, | ||
42 | /* | ||
43 | * add more here as they are defined in radiotap.h | ||
44 | */ | ||
45 | }; | ||
46 | |||
47 | static const struct ieee80211_radiotap_namespace radiotap_ns = { | ||
48 | .n_bits = sizeof(rtap_namespace_sizes) / sizeof(rtap_namespace_sizes[0]), | ||
49 | .align_size = rtap_namespace_sizes, | ||
50 | }; | ||
51 | |||
13 | /** | 52 | /** |
14 | * ieee80211_radiotap_iterator_init - radiotap parser iterator initialization | 53 | * ieee80211_radiotap_iterator_init - radiotap parser iterator initialization |
15 | * @iterator: radiotap_iterator to initialize | 54 | * @iterator: radiotap_iterator to initialize |
@@ -50,9 +89,9 @@ | |||
50 | */ | 89 | */ |
51 | 90 | ||
52 | int ieee80211_radiotap_iterator_init( | 91 | int ieee80211_radiotap_iterator_init( |
53 | struct ieee80211_radiotap_iterator *iterator, | 92 | struct ieee80211_radiotap_iterator *iterator, |
54 | struct ieee80211_radiotap_header *radiotap_header, | 93 | struct ieee80211_radiotap_header *radiotap_header, |
55 | int max_length) | 94 | int max_length, const struct ieee80211_radiotap_vendor_namespaces *vns) |
56 | { | 95 | { |
57 | /* Linux only supports version 0 radiotap format */ | 96 | /* Linux only supports version 0 radiotap format */ |
58 | if (radiotap_header->it_version) | 97 | if (radiotap_header->it_version) |
@@ -62,19 +101,24 @@ int ieee80211_radiotap_iterator_init( | |||
62 | if (max_length < get_unaligned_le16(&radiotap_header->it_len)) | 101 | if (max_length < get_unaligned_le16(&radiotap_header->it_len)) |
63 | return -EINVAL; | 102 | return -EINVAL; |
64 | 103 | ||
65 | iterator->rtheader = radiotap_header; | 104 | iterator->_rtheader = radiotap_header; |
66 | iterator->max_length = get_unaligned_le16(&radiotap_header->it_len); | 105 | iterator->_max_length = get_unaligned_le16(&radiotap_header->it_len); |
67 | iterator->arg_index = 0; | 106 | iterator->_arg_index = 0; |
68 | iterator->bitmap_shifter = get_unaligned_le32(&radiotap_header->it_present); | 107 | iterator->_bitmap_shifter = get_unaligned_le32(&radiotap_header->it_present); |
69 | iterator->arg = (u8 *)radiotap_header + sizeof(*radiotap_header); | 108 | iterator->_arg = (uint8_t *)radiotap_header + sizeof(*radiotap_header); |
70 | iterator->this_arg = NULL; | 109 | iterator->_reset_on_ext = 0; |
110 | iterator->_next_bitmap = &radiotap_header->it_present; | ||
111 | iterator->_next_bitmap++; | ||
112 | iterator->_vns = vns; | ||
113 | iterator->current_namespace = &radiotap_ns; | ||
114 | iterator->is_radiotap_ns = 1; | ||
71 | 115 | ||
72 | /* find payload start allowing for extended bitmap(s) */ | 116 | /* find payload start allowing for extended bitmap(s) */ |
73 | 117 | ||
74 | if (unlikely(iterator->bitmap_shifter & (1<<IEEE80211_RADIOTAP_EXT))) { | 118 | if (iterator->_bitmap_shifter & (1<<IEEE80211_RADIOTAP_EXT)) { |
75 | while (get_unaligned_le32(iterator->arg) & | 119 | while (get_unaligned_le32(iterator->_arg) & |
76 | (1 << IEEE80211_RADIOTAP_EXT)) { | 120 | (1 << IEEE80211_RADIOTAP_EXT)) { |
77 | iterator->arg += sizeof(u32); | 121 | iterator->_arg += sizeof(uint32_t); |
78 | 122 | ||
79 | /* | 123 | /* |
80 | * check for insanity where the present bitmaps | 124 | * check for insanity where the present bitmaps |
@@ -82,12 +126,13 @@ int ieee80211_radiotap_iterator_init( | |||
82 | * stated radiotap header length | 126 | * stated radiotap header length |
83 | */ | 127 | */ |
84 | 128 | ||
85 | if (((ulong)iterator->arg - | 129 | if ((unsigned long)iterator->_arg - |
86 | (ulong)iterator->rtheader) > iterator->max_length) | 130 | (unsigned long)iterator->_rtheader > |
131 | (unsigned long)iterator->_max_length) | ||
87 | return -EINVAL; | 132 | return -EINVAL; |
88 | } | 133 | } |
89 | 134 | ||
90 | iterator->arg += sizeof(u32); | 135 | iterator->_arg += sizeof(uint32_t); |
91 | 136 | ||
92 | /* | 137 | /* |
93 | * no need to check again for blowing past stated radiotap | 138 | * no need to check again for blowing past stated radiotap |
@@ -96,12 +141,36 @@ int ieee80211_radiotap_iterator_init( | |||
96 | */ | 141 | */ |
97 | } | 142 | } |
98 | 143 | ||
144 | iterator->this_arg = iterator->_arg; | ||
145 | |||
99 | /* we are all initialized happily */ | 146 | /* we are all initialized happily */ |
100 | 147 | ||
101 | return 0; | 148 | return 0; |
102 | } | 149 | } |
103 | EXPORT_SYMBOL(ieee80211_radiotap_iterator_init); | 150 | EXPORT_SYMBOL(ieee80211_radiotap_iterator_init); |
104 | 151 | ||
152 | static void find_ns(struct ieee80211_radiotap_iterator *iterator, | ||
153 | uint32_t oui, uint8_t subns) | ||
154 | { | ||
155 | int i; | ||
156 | |||
157 | iterator->current_namespace = NULL; | ||
158 | |||
159 | if (!iterator->_vns) | ||
160 | return; | ||
161 | |||
162 | for (i = 0; i < iterator->_vns->n_ns; i++) { | ||
163 | if (iterator->_vns->ns[i].oui != oui) | ||
164 | continue; | ||
165 | if (iterator->_vns->ns[i].subns != subns) | ||
166 | continue; | ||
167 | |||
168 | iterator->current_namespace = &iterator->_vns->ns[i]; | ||
169 | break; | ||
170 | } | ||
171 | } | ||
172 | |||
173 | |||
105 | 174 | ||
106 | /** | 175 | /** |
107 | * ieee80211_radiotap_iterator_next - return next radiotap parser iterator arg | 176 | * ieee80211_radiotap_iterator_next - return next radiotap parser iterator arg |
@@ -127,99 +196,80 @@ EXPORT_SYMBOL(ieee80211_radiotap_iterator_init); | |||
127 | */ | 196 | */ |
128 | 197 | ||
129 | int ieee80211_radiotap_iterator_next( | 198 | int ieee80211_radiotap_iterator_next( |
130 | struct ieee80211_radiotap_iterator *iterator) | 199 | struct ieee80211_radiotap_iterator *iterator) |
131 | { | 200 | { |
132 | 201 | while (1) { | |
133 | /* | ||
134 | * small length lookup table for all radiotap types we heard of | ||
135 | * starting from b0 in the bitmap, so we can walk the payload | ||
136 | * area of the radiotap header | ||
137 | * | ||
138 | * There is a requirement to pad args, so that args | ||
139 | * of a given length must begin at a boundary of that length | ||
140 | * -- but note that compound args are allowed (eg, 2 x u16 | ||
141 | * for IEEE80211_RADIOTAP_CHANNEL) so total arg length is not | ||
142 | * a reliable indicator of alignment requirement. | ||
143 | * | ||
144 | * upper nybble: content alignment for arg | ||
145 | * lower nybble: content length for arg | ||
146 | */ | ||
147 | |||
148 | static const u8 rt_sizes[] = { | ||
149 | [IEEE80211_RADIOTAP_TSFT] = 0x88, | ||
150 | [IEEE80211_RADIOTAP_FLAGS] = 0x11, | ||
151 | [IEEE80211_RADIOTAP_RATE] = 0x11, | ||
152 | [IEEE80211_RADIOTAP_CHANNEL] = 0x24, | ||
153 | [IEEE80211_RADIOTAP_FHSS] = 0x22, | ||
154 | [IEEE80211_RADIOTAP_DBM_ANTSIGNAL] = 0x11, | ||
155 | [IEEE80211_RADIOTAP_DBM_ANTNOISE] = 0x11, | ||
156 | [IEEE80211_RADIOTAP_LOCK_QUALITY] = 0x22, | ||
157 | [IEEE80211_RADIOTAP_TX_ATTENUATION] = 0x22, | ||
158 | [IEEE80211_RADIOTAP_DB_TX_ATTENUATION] = 0x22, | ||
159 | [IEEE80211_RADIOTAP_DBM_TX_POWER] = 0x11, | ||
160 | [IEEE80211_RADIOTAP_ANTENNA] = 0x11, | ||
161 | [IEEE80211_RADIOTAP_DB_ANTSIGNAL] = 0x11, | ||
162 | [IEEE80211_RADIOTAP_DB_ANTNOISE] = 0x11, | ||
163 | [IEEE80211_RADIOTAP_RX_FLAGS] = 0x22, | ||
164 | [IEEE80211_RADIOTAP_TX_FLAGS] = 0x22, | ||
165 | [IEEE80211_RADIOTAP_RTS_RETRIES] = 0x11, | ||
166 | [IEEE80211_RADIOTAP_DATA_RETRIES] = 0x11, | ||
167 | /* | ||
168 | * add more here as they are defined in | ||
169 | * include/net/ieee80211_radiotap.h | ||
170 | */ | ||
171 | }; | ||
172 | |||
173 | /* | ||
174 | * for every radiotap entry we can at | ||
175 | * least skip (by knowing the length)... | ||
176 | */ | ||
177 | |||
178 | while (iterator->arg_index < sizeof(rt_sizes)) { | ||
179 | int hit = 0; | 202 | int hit = 0; |
180 | int pad; | 203 | int pad, align, size, subns, vnslen; |
204 | uint32_t oui; | ||
181 | 205 | ||
182 | if (!(iterator->bitmap_shifter & 1)) | 206 | /* if no more EXT bits, that's it */ |
207 | if ((iterator->_arg_index % 32) == IEEE80211_RADIOTAP_EXT && | ||
208 | !(iterator->_bitmap_shifter & 1)) | ||
209 | return -ENOENT; | ||
210 | |||
211 | if (!(iterator->_bitmap_shifter & 1)) | ||
183 | goto next_entry; /* arg not present */ | 212 | goto next_entry; /* arg not present */ |
184 | 213 | ||
214 | /* get alignment/size of data */ | ||
215 | switch (iterator->_arg_index % 32) { | ||
216 | case IEEE80211_RADIOTAP_RADIOTAP_NAMESPACE: | ||
217 | case IEEE80211_RADIOTAP_EXT: | ||
218 | align = 1; | ||
219 | size = 0; | ||
220 | break; | ||
221 | case IEEE80211_RADIOTAP_VENDOR_NAMESPACE: | ||
222 | align = 2; | ||
223 | size = 6; | ||
224 | break; | ||
225 | default: | ||
226 | if (!iterator->current_namespace || | ||
227 | iterator->_arg_index >= iterator->current_namespace->n_bits) { | ||
228 | if (iterator->current_namespace == &radiotap_ns) | ||
229 | return -ENOENT; | ||
230 | align = 0; | ||
231 | } else { | ||
232 | align = iterator->current_namespace->align_size[iterator->_arg_index].align; | ||
233 | size = iterator->current_namespace->align_size[iterator->_arg_index].size; | ||
234 | } | ||
235 | if (!align) { | ||
236 | /* skip all subsequent data */ | ||
237 | iterator->_arg = iterator->_next_ns_data; | ||
238 | /* give up on this namespace */ | ||
239 | iterator->current_namespace = NULL; | ||
240 | goto next_entry; | ||
241 | } | ||
242 | break; | ||
243 | } | ||
244 | |||
185 | /* | 245 | /* |
186 | * arg is present, account for alignment padding | 246 | * arg is present, account for alignment padding |
187 | * 8-bit args can be at any alignment | ||
188 | * 16-bit args must start on 16-bit boundary | ||
189 | * 32-bit args must start on 32-bit boundary | ||
190 | * 64-bit args must start on 64-bit boundary | ||
191 | * | 247 | * |
192 | * note that total arg size can differ from alignment of | 248 | * Note that these alignments are relative to the start |
193 | * elements inside arg, so we use upper nybble of length | 249 | * of the radiotap header. There is no guarantee |
194 | * table to base alignment on | ||
195 | * | ||
196 | * also note: these alignments are ** relative to the | ||
197 | * start of the radiotap header **. There is no guarantee | ||
198 | * that the radiotap header itself is aligned on any | 250 | * that the radiotap header itself is aligned on any |
199 | * kind of boundary. | 251 | * kind of boundary. |
200 | * | 252 | * |
201 | * the above is why get_unaligned() is used to dereference | 253 | * The above is why get_unaligned() is used to dereference |
202 | * multibyte elements from the radiotap area | 254 | * multibyte elements from the radiotap area. |
203 | */ | 255 | */ |
204 | 256 | ||
205 | pad = (((ulong)iterator->arg) - | 257 | pad = ((unsigned long)iterator->_arg - |
206 | ((ulong)iterator->rtheader)) & | 258 | (unsigned long)iterator->_rtheader) & (align - 1); |
207 | ((rt_sizes[iterator->arg_index] >> 4) - 1); | ||
208 | 259 | ||
209 | if (pad) | 260 | if (pad) |
210 | iterator->arg += | 261 | iterator->_arg += align - pad; |
211 | (rt_sizes[iterator->arg_index] >> 4) - pad; | ||
212 | 262 | ||
213 | /* | 263 | /* |
214 | * this is what we will return to user, but we need to | 264 | * this is what we will return to user, but we need to |
215 | * move on first so next call has something fresh to test | 265 | * move on first so next call has something fresh to test |
216 | */ | 266 | */ |
217 | iterator->this_arg_index = iterator->arg_index; | 267 | iterator->this_arg_index = iterator->_arg_index; |
218 | iterator->this_arg = iterator->arg; | 268 | iterator->this_arg = iterator->_arg; |
219 | hit = 1; | 269 | iterator->this_arg_size = size; |
220 | 270 | ||
221 | /* internally move on the size of this arg */ | 271 | /* internally move on the size of this arg */ |
222 | iterator->arg += rt_sizes[iterator->arg_index] & 0x0f; | 272 | iterator->_arg += size; |
223 | 273 | ||
224 | /* | 274 | /* |
225 | * check for insanity where we are given a bitmap that | 275 | * check for insanity where we are given a bitmap that |
@@ -228,32 +278,73 @@ int ieee80211_radiotap_iterator_next( | |||
228 | * max_length on the last arg, never exceeding it. | 278 | * max_length on the last arg, never exceeding it. |
229 | */ | 279 | */ |
230 | 280 | ||
231 | if (((ulong)iterator->arg - (ulong)iterator->rtheader) > | 281 | if ((unsigned long)iterator->_arg - |
232 | iterator->max_length) | 282 | (unsigned long)iterator->_rtheader > |
283 | (unsigned long)iterator->_max_length) | ||
233 | return -EINVAL; | 284 | return -EINVAL; |
234 | 285 | ||
235 | next_entry: | 286 | /* these special ones are valid in each bitmap word */ |
236 | iterator->arg_index++; | 287 | switch (iterator->_arg_index % 32) { |
237 | if (unlikely((iterator->arg_index & 31) == 0)) { | 288 | case IEEE80211_RADIOTAP_VENDOR_NAMESPACE: |
238 | /* completed current u32 bitmap */ | 289 | iterator->_bitmap_shifter >>= 1; |
239 | if (iterator->bitmap_shifter & 1) { | 290 | iterator->_arg_index++; |
240 | /* b31 was set, there is more */ | 291 | |
241 | /* move to next u32 bitmap */ | 292 | iterator->_reset_on_ext = 1; |
242 | iterator->bitmap_shifter = | 293 | |
243 | get_unaligned_le32(iterator->next_bitmap); | 294 | vnslen = get_unaligned_le16(iterator->this_arg + 4); |
244 | iterator->next_bitmap++; | 295 | iterator->_next_ns_data = iterator->_arg + vnslen; |
245 | } else | 296 | oui = (*iterator->this_arg << 16) | |
246 | /* no more bitmaps: end */ | 297 | (*(iterator->this_arg + 1) << 8) | |
247 | iterator->arg_index = sizeof(rt_sizes); | 298 | *(iterator->this_arg + 2); |
248 | } else /* just try the next bit */ | 299 | subns = *(iterator->this_arg + 3); |
249 | iterator->bitmap_shifter >>= 1; | 300 | |
301 | find_ns(iterator, oui, subns); | ||
302 | |||
303 | iterator->is_radiotap_ns = 0; | ||
304 | /* allow parsers to show this information */ | ||
305 | iterator->this_arg_index = | ||
306 | IEEE80211_RADIOTAP_VENDOR_NAMESPACE; | ||
307 | iterator->this_arg_size += vnslen; | ||
308 | if ((unsigned long)iterator->this_arg + | ||
309 | iterator->this_arg_size - | ||
310 | (unsigned long)iterator->_rtheader > | ||
311 | (unsigned long)(unsigned long)iterator->_max_length) | ||
312 | return -EINVAL; | ||
313 | hit = 1; | ||
314 | break; | ||
315 | case IEEE80211_RADIOTAP_RADIOTAP_NAMESPACE: | ||
316 | iterator->_bitmap_shifter >>= 1; | ||
317 | iterator->_arg_index++; | ||
318 | |||
319 | iterator->_reset_on_ext = 1; | ||
320 | iterator->current_namespace = &radiotap_ns; | ||
321 | iterator->is_radiotap_ns = 1; | ||
322 | break; | ||
323 | case IEEE80211_RADIOTAP_EXT: | ||
324 | /* | ||
325 | * bit 31 was set, there is more | ||
326 | * -- move to next u32 bitmap | ||
327 | */ | ||
328 | iterator->_bitmap_shifter = | ||
329 | get_unaligned_le32(iterator->_next_bitmap); | ||
330 | iterator->_next_bitmap++; | ||
331 | if (iterator->_reset_on_ext) | ||
332 | iterator->_arg_index = 0; | ||
333 | else | ||
334 | iterator->_arg_index++; | ||
335 | iterator->_reset_on_ext = 0; | ||
336 | break; | ||
337 | default: | ||
338 | /* we've got a hit! */ | ||
339 | hit = 1; | ||
340 | next_entry: | ||
341 | iterator->_bitmap_shifter >>= 1; | ||
342 | iterator->_arg_index++; | ||
343 | } | ||
250 | 344 | ||
251 | /* if we found a valid arg earlier, return it now */ | 345 | /* if we found a valid arg earlier, return it now */ |
252 | if (hit) | 346 | if (hit) |
253 | return 0; | 347 | return 0; |
254 | } | 348 | } |
255 | |||
256 | /* we don't know how to handle any more args, we're done */ | ||
257 | return -ENOENT; | ||
258 | } | 349 | } |
259 | EXPORT_SYMBOL(ieee80211_radiotap_iterator_next); | 350 | EXPORT_SYMBOL(ieee80211_radiotap_iterator_next); |