Line data Source code
1 : /*
2 : * P2P - generic helper functions
3 : * Copyright (c) 2009, Atheros Communications
4 : *
5 : * This software may be distributed under the terms of the BSD license.
6 : * See README for more details.
7 : */
8 :
9 : #include "includes.h"
10 :
11 : #include "common.h"
12 : #include "p2p_i.h"
13 :
14 :
15 : /**
16 : * p2p_random - Generate random string for SSID and passphrase
17 : * @buf: Buffer for returning the result
18 : * @len: Number of octets to write to the buffer
19 : * Returns: 0 on success, -1 on failure
20 : *
21 : * This function generates a random string using the following character set:
22 : * 'A'-'Z', 'a'-'z', '0'-'9'.
23 : */
24 201 : int p2p_random(char *buf, size_t len)
25 : {
26 : u8 val;
27 : size_t i;
28 201 : u8 letters = 'Z' - 'A' + 1;
29 201 : u8 numbers = 10;
30 :
31 201 : if (os_get_random((unsigned char *) buf, len))
32 0 : return -1;
33 : /* Character set: 'A'-'Z', 'a'-'z', '0'-'9' */
34 1209 : for (i = 0; i < len; i++) {
35 1008 : val = buf[i];
36 1008 : val %= 2 * letters + numbers;
37 1008 : if (val < letters)
38 433 : buf[i] = 'A' + val;
39 575 : else if (val < 2 * letters)
40 417 : buf[i] = 'a' + (val - letters);
41 : else
42 158 : buf[i] = '0' + (val - 2 * letters);
43 : }
44 :
45 201 : return 0;
46 : }
47 :
48 :
49 : /**
50 : * p2p_channel_to_freq - Convert channel info to frequency
51 : * @op_class: Operating class
52 : * @channel: Channel number
53 : * Returns: Frequency in MHz or -1 if the specified channel is unknown
54 : */
55 5993 : int p2p_channel_to_freq(int op_class, int channel)
56 : {
57 : /* Table E-4 in IEEE Std 802.11-2012 - Global operating classes */
58 : /* TODO: more operating classes */
59 5993 : switch (op_class) {
60 : case 81:
61 : /* channels 1..13 */
62 5713 : if (channel < 1 || channel > 13)
63 1 : return -1;
64 5712 : return 2407 + 5 * channel;
65 : case 82:
66 : /* channel 14 */
67 0 : if (channel != 14)
68 0 : return -1;
69 0 : return 2414 + 5 * channel;
70 : case 83: /* channels 1..9; 40 MHz */
71 : case 84: /* channels 5..13; 40 MHz */
72 0 : if (channel < 1 || channel > 13)
73 0 : return -1;
74 0 : return 2407 + 5 * channel;
75 : case 115: /* channels 36,40,44,48; indoor only */
76 : case 118: /* channels 52,56,60,64; dfs */
77 51 : if (channel < 36 || channel > 64)
78 1 : return -1;
79 50 : return 5000 + 5 * channel;
80 : case 124: /* channels 149,153,157,161 */
81 : case 125: /* channels 149,153,157,161,165,169 */
82 65 : if (channel < 149 || channel > 161)
83 0 : return -1;
84 65 : return 5000 + 5 * channel;
85 : case 116: /* channels 36,44; 40 MHz; indoor only */
86 : case 117: /* channels 40,48; 40 MHz; indoor only */
87 : case 119: /* channels 52,60; 40 MHz; dfs */
88 : case 120: /* channels 56,64; 40 MHz; dfs */
89 44 : if (channel < 36 || channel > 64)
90 0 : return -1;
91 44 : return 5000 + 5 * channel;
92 : case 126: /* channels 149,157; 40 MHz */
93 : case 127: /* channels 153,161; 40 MHz */
94 68 : if (channel < 149 || channel > 161)
95 0 : return -1;
96 68 : return 5000 + 5 * channel;
97 : case 128: /* center freqs 42, 58, 106, 122, 138, 155; 80 MHz */
98 52 : if (channel < 36 || channel > 161)
99 0 : return -1;
100 52 : return 5000 + 5 * channel;
101 : case 180: /* 60 GHz band, channels 1..4 */
102 0 : if (channel < 1 || channel > 4)
103 0 : return -1;
104 0 : return 56160 + 2160 * channel;
105 : }
106 0 : return -1;
107 : }
108 :
109 :
110 : /**
111 : * p2p_freq_to_channel - Convert frequency into channel info
112 : * @op_class: Buffer for returning operating class
113 : * @channel: Buffer for returning channel number
114 : * Returns: 0 on success, -1 if the specified frequency is unknown
115 : */
116 163 : int p2p_freq_to_channel(unsigned int freq, u8 *op_class, u8 *channel)
117 : {
118 : /* TODO: more operating classes */
119 163 : if (freq >= 2412 && freq <= 2472) {
120 163 : if ((freq - 2407) % 5)
121 0 : return -1;
122 :
123 163 : *op_class = 81; /* 2.407 GHz, channels 1..13 */
124 163 : *channel = (freq - 2407) / 5;
125 163 : return 0;
126 : }
127 :
128 0 : if (freq == 2484) {
129 0 : *op_class = 82; /* channel 14 */
130 0 : *channel = 14;
131 0 : return 0;
132 : }
133 :
134 0 : if (freq >= 5180 && freq <= 5240) {
135 0 : if ((freq - 5000) % 5)
136 0 : return -1;
137 :
138 0 : *op_class = 115; /* 5 GHz, channels 36..48 */
139 0 : *channel = (freq - 5000) / 5;
140 0 : return 0;
141 : }
142 :
143 0 : if (freq >= 5745 && freq <= 5805) {
144 0 : if ((freq - 5000) % 5)
145 0 : return -1;
146 :
147 0 : *op_class = 124; /* 5 GHz, channels 149..161 */
148 0 : *channel = (freq - 5000) / 5;
149 0 : return 0;
150 : }
151 :
152 0 : return -1;
153 : }
154 :
155 :
156 717 : static void p2p_reg_class_intersect(const struct p2p_reg_class *a,
157 : const struct p2p_reg_class *b,
158 : struct p2p_reg_class *res)
159 : {
160 : size_t i, j;
161 :
162 717 : res->reg_class = a->reg_class;
163 :
164 7054 : for (i = 0; i < a->channels; i++) {
165 71401 : for (j = 0; j < b->channels; j++) {
166 65064 : if (a->channel[i] != b->channel[j])
167 59333 : continue;
168 5731 : res->channel[res->channels] = a->channel[i];
169 5731 : res->channels++;
170 5731 : if (res->channels == P2P_MAX_REG_CLASS_CHANNELS)
171 717 : return;
172 : }
173 : }
174 : }
175 :
176 :
177 : /**
178 : * p2p_channels_intersect - Intersection of supported channel lists
179 : * @a: First set of supported channels
180 : * @b: Second set of supported channels
181 : * @res: Data structure for returning the intersection of support channels
182 : *
183 : * This function can be used to find a common set of supported channels. Both
184 : * input channels sets are assumed to use the same country code. If different
185 : * country codes are used, the regulatory class numbers may not be matched
186 : * correctly and results are undefined.
187 : */
188 610 : void p2p_channels_intersect(const struct p2p_channels *a,
189 : const struct p2p_channels *b,
190 : struct p2p_channels *res)
191 : {
192 : size_t i, j;
193 :
194 610 : os_memset(res, 0, sizeof(*res));
195 :
196 1416 : for (i = 0; i < a->reg_classes; i++) {
197 806 : const struct p2p_reg_class *a_reg = &a->reg_class[i];
198 2664 : for (j = 0; j < b->reg_classes; j++) {
199 1858 : const struct p2p_reg_class *b_reg = &b->reg_class[j];
200 1858 : if (a_reg->reg_class != b_reg->reg_class)
201 1141 : continue;
202 717 : p2p_reg_class_intersect(
203 : a_reg, b_reg,
204 717 : &res->reg_class[res->reg_classes]);
205 717 : if (res->reg_class[res->reg_classes].channels) {
206 716 : res->reg_classes++;
207 716 : if (res->reg_classes == P2P_MAX_REG_CLASSES)
208 610 : return;
209 : }
210 : }
211 : }
212 : }
213 :
214 :
215 3 : static void p2p_op_class_union(struct p2p_reg_class *cl,
216 : const struct p2p_reg_class *b_cl)
217 : {
218 : size_t i, j;
219 :
220 6 : for (i = 0; i < b_cl->channels; i++) {
221 39 : for (j = 0; j < cl->channels; j++) {
222 36 : if (b_cl->channel[i] == cl->channel[j])
223 0 : break;
224 : }
225 3 : if (j == cl->channels) {
226 3 : if (cl->channels == P2P_MAX_REG_CLASS_CHANNELS)
227 3 : return;
228 3 : cl->channel[cl->channels++] = b_cl->channel[i];
229 : }
230 : }
231 : }
232 :
233 :
234 : /**
235 : * p2p_channels_union - Union of channel lists
236 : * @a: First set of channels
237 : * @b: Second set of channels
238 : * @res: Data structure for returning the union of channels
239 : */
240 102 : void p2p_channels_union(const struct p2p_channels *a,
241 : const struct p2p_channels *b,
242 : struct p2p_channels *res)
243 : {
244 : size_t i, j;
245 :
246 102 : if (a != res)
247 0 : os_memcpy(res, a, sizeof(*res));
248 :
249 253 : for (i = 0; i < res->reg_classes; i++) {
250 151 : struct p2p_reg_class *cl = &res->reg_class[i];
251 175 : for (j = 0; j < b->reg_classes; j++) {
252 24 : const struct p2p_reg_class *b_cl = &b->reg_class[j];
253 24 : if (cl->reg_class != b_cl->reg_class)
254 21 : continue;
255 3 : p2p_op_class_union(cl, b_cl);
256 : }
257 : }
258 :
259 126 : for (j = 0; j < b->reg_classes; j++) {
260 24 : const struct p2p_reg_class *b_cl = &b->reg_class[j];
261 :
262 108 : for (i = 0; i < res->reg_classes; i++) {
263 87 : struct p2p_reg_class *cl = &res->reg_class[i];
264 87 : if (cl->reg_class == b_cl->reg_class)
265 3 : break;
266 : }
267 :
268 24 : if (i == res->reg_classes) {
269 21 : if (res->reg_classes == P2P_MAX_REG_CLASSES)
270 102 : return;
271 21 : os_memcpy(&res->reg_class[res->reg_classes++],
272 : b_cl, sizeof(struct p2p_reg_class));
273 : }
274 : }
275 : }
276 :
277 :
278 201 : void p2p_channels_remove_freqs(struct p2p_channels *chan,
279 : const struct wpa_freq_range_list *list)
280 : {
281 : size_t o, c;
282 :
283 201 : if (list == NULL)
284 201 : return;
285 :
286 201 : o = 0;
287 654 : while (o < chan->reg_classes) {
288 252 : struct p2p_reg_class *op = &chan->reg_class[o];
289 :
290 252 : c = 0;
291 2511 : while (c < op->channels) {
292 2007 : int freq = p2p_channel_to_freq(op->reg_class,
293 2007 : op->channel[c]);
294 2007 : if (freq > 0 && freq_range_list_includes(list, freq)) {
295 13 : op->channels--;
296 13 : os_memmove(&op->channel[c],
297 : &op->channel[c + 1],
298 : op->channels - c);
299 : } else
300 1994 : c++;
301 : }
302 :
303 252 : if (op->channels == 0) {
304 2 : chan->reg_classes--;
305 2 : os_memmove(&chan->reg_class[o], &chan->reg_class[o + 1],
306 : (chan->reg_classes - o) *
307 : sizeof(struct p2p_reg_class));
308 : } else
309 250 : o++;
310 : }
311 : }
312 :
313 :
314 : /**
315 : * p2p_channels_includes - Check whether a channel is included in the list
316 : * @channels: List of supported channels
317 : * @reg_class: Regulatory class of the channel to search
318 : * @channel: Channel number of the channel to search
319 : * Returns: 1 if channel was found or 0 if not
320 : */
321 447 : int p2p_channels_includes(const struct p2p_channels *channels, u8 reg_class,
322 : u8 channel)
323 : {
324 : size_t i, j;
325 481 : for (i = 0; i < channels->reg_classes; i++) {
326 463 : const struct p2p_reg_class *reg = &channels->reg_class[i];
327 463 : if (reg->reg_class != reg_class)
328 17 : continue;
329 2918 : for (j = 0; j < reg->channels; j++) {
330 2901 : if (reg->channel[j] == channel)
331 429 : return 1;
332 : }
333 : }
334 18 : return 0;
335 : }
336 :
337 :
338 144 : int p2p_channels_includes_freq(const struct p2p_channels *channels,
339 : unsigned int freq)
340 : {
341 : size_t i, j;
342 159 : for (i = 0; i < channels->reg_classes; i++) {
343 154 : const struct p2p_reg_class *reg = &channels->reg_class[i];
344 1013 : for (j = 0; j < reg->channels; j++) {
345 1996 : if (p2p_channel_to_freq(reg->reg_class,
346 1996 : reg->channel[j]) == (int) freq)
347 139 : return 1;
348 : }
349 : }
350 5 : return 0;
351 : }
352 :
353 :
354 22 : int p2p_supported_freq(struct p2p_data *p2p, unsigned int freq)
355 : {
356 : u8 op_reg_class, op_channel;
357 22 : if (p2p_freq_to_channel(freq, &op_reg_class, &op_channel) < 0)
358 0 : return 0;
359 22 : return p2p_channels_includes(&p2p->cfg->channels, op_reg_class,
360 : op_channel);
361 : }
362 :
363 :
364 80 : int p2p_supported_freq_go(struct p2p_data *p2p, unsigned int freq)
365 : {
366 : u8 op_reg_class, op_channel;
367 80 : if (p2p_freq_to_channel(freq, &op_reg_class, &op_channel) < 0)
368 0 : return 0;
369 160 : return p2p_channels_includes(&p2p->cfg->channels, op_reg_class,
370 160 : op_channel) &&
371 80 : !freq_range_list_includes(&p2p->no_go_freq, freq);
372 : }
373 :
374 :
375 17 : int p2p_supported_freq_cli(struct p2p_data *p2p, unsigned int freq)
376 : {
377 : u8 op_reg_class, op_channel;
378 17 : if (p2p_freq_to_channel(freq, &op_reg_class, &op_channel) < 0)
379 0 : return 0;
380 34 : return p2p_channels_includes(&p2p->cfg->channels, op_reg_class,
381 17 : op_channel) ||
382 0 : p2p_channels_includes(&p2p->cfg->cli_channels, op_reg_class,
383 : op_channel);
384 : }
385 :
386 :
387 6 : unsigned int p2p_get_pref_freq(struct p2p_data *p2p,
388 : const struct p2p_channels *channels)
389 : {
390 : unsigned int i;
391 : int freq;
392 :
393 6 : for (i = 0; p2p->cfg->pref_chan && i < p2p->cfg->num_pref_chan; i++) {
394 0 : freq = p2p_channel_to_freq(p2p->cfg->pref_chan[i].op_class,
395 0 : p2p->cfg->pref_chan[i].chan);
396 0 : if (freq <= 0)
397 0 : continue;
398 0 : if (!channels || p2p_channels_includes_freq(channels, freq))
399 0 : return freq;
400 : }
401 :
402 6 : return 0;
403 : }
404 :
405 :
406 6475 : void p2p_channels_dump(struct p2p_data *p2p, const char *title,
407 : const struct p2p_channels *chan)
408 : {
409 : char buf[500], *pos, *end;
410 : size_t i, j;
411 : int ret;
412 :
413 6475 : pos = buf;
414 6475 : end = pos + sizeof(buf);
415 :
416 11467 : for (i = 0; i < chan->reg_classes; i++) {
417 : const struct p2p_reg_class *c;
418 4992 : c = &chan->reg_class[i];
419 4992 : ret = os_snprintf(pos, end - pos, " %u:", c->reg_class);
420 4992 : if (ret < 0 || ret >= end - pos)
421 : break;
422 4992 : pos += ret;
423 :
424 51362 : for (j = 0; j < c->channels; j++) {
425 46370 : ret = os_snprintf(pos, end - pos, "%s%u",
426 : j == 0 ? "" : ",",
427 46370 : c->channel[j]);
428 46370 : if (ret < 0 || ret >= end - pos)
429 : break;
430 46370 : pos += ret;
431 : }
432 : }
433 6475 : *pos = '\0';
434 :
435 6475 : p2p_dbg(p2p, "%s:%s", title, buf);
436 6475 : }
437 :
438 :
439 16 : static u8 p2p_channel_pick_random(const u8 *channels, unsigned int num_channels)
440 : {
441 : unsigned int r;
442 16 : os_get_random((u8 *) &r, sizeof(r));
443 16 : r %= num_channels;
444 16 : return channels[r];
445 : }
446 :
447 :
448 557 : int p2p_channel_select(struct p2p_channels *chans, const int *classes,
449 : u8 *op_class, u8 *op_channel)
450 : {
451 : unsigned int i, j;
452 :
453 1819 : for (j = 0; classes == NULL || classes[j]; j++) {
454 2626 : for (i = 0; i < chans->reg_classes; i++) {
455 1364 : struct p2p_reg_class *c = &chans->reg_class[i];
456 :
457 1364 : if (c->channels == 0)
458 0 : continue;
459 :
460 1364 : if (classes == NULL || c->reg_class == classes[j]) {
461 : /*
462 : * Pick one of the available channels in the
463 : * operating class at random.
464 : */
465 15 : *op_class = c->reg_class;
466 30 : *op_channel = p2p_channel_pick_random(
467 30 : c->channel, c->channels);
468 15 : return 0;
469 : }
470 : }
471 1262 : if (classes == NULL)
472 0 : break;
473 : }
474 :
475 542 : return -1;
476 : }
477 :
478 :
479 3 : int p2p_channel_random_social(struct p2p_channels *chans, u8 *op_class,
480 : u8 *op_channel)
481 : {
482 : u8 chan[3];
483 3 : unsigned int num_channels = 0;
484 :
485 : /* Try to find available social channels from 2.4 GHz */
486 3 : if (p2p_channels_includes(chans, 81, 1))
487 1 : chan[num_channels++] = 1;
488 3 : if (p2p_channels_includes(chans, 81, 6))
489 1 : chan[num_channels++] = 6;
490 3 : if (p2p_channels_includes(chans, 81, 11))
491 1 : chan[num_channels++] = 11;
492 :
493 3 : if (num_channels == 0)
494 2 : return -1;
495 :
496 1 : *op_class = 81;
497 1 : *op_channel = p2p_channel_pick_random(chan, num_channels);
498 :
499 1 : return 0;
500 : }
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