]>
Commit | Line | Data |
---|---|---|
04ea7b79 JM |
1 | /* |
2 | * Generic advertisement service (GAS) query | |
3 | * Copyright (c) 2009, Atheros Communications | |
4 | * Copyright (c) 2011, Qualcomm Atheros | |
5 | * | |
e22d4d95 JM |
6 | * This software may be distributed under the terms of the BSD license. |
7 | * See README for more details. | |
04ea7b79 JM |
8 | */ |
9 | ||
10 | #include "includes.h" | |
11 | ||
12 | #include "common.h" | |
13 | #include "utils/eloop.h" | |
14 | #include "common/ieee802_11_defs.h" | |
15 | #include "common/gas.h" | |
16 | #include "wpa_supplicant_i.h" | |
17 | #include "driver_i.h" | |
24f6497c | 18 | #include "offchannel.h" |
04ea7b79 JM |
19 | #include "gas_query.h" |
20 | ||
21 | ||
22 | #define GAS_QUERY_TIMEOUT 5 | |
23 | ||
24 | ||
25 | struct gas_query_pending { | |
26 | struct dl_list list; | |
27 | u8 addr[ETH_ALEN]; | |
28 | u8 dialog_token; | |
29 | u8 next_frag_id; | |
298716b4 JM |
30 | unsigned int wait_comeback:1; |
31 | unsigned int offchannel_tx_started:1; | |
04ea7b79 JM |
32 | int freq; |
33 | u16 status_code; | |
34 | struct wpabuf *adv_proto; | |
35 | struct wpabuf *resp; | |
36 | void (*cb)(void *ctx, const u8 *dst, u8 dialog_token, | |
37 | enum gas_query_result result, | |
38 | const struct wpabuf *adv_proto, | |
39 | const struct wpabuf *resp, u16 status_code); | |
40 | void *ctx; | |
41 | }; | |
42 | ||
43 | struct gas_query { | |
44 | struct wpa_supplicant *wpa_s; | |
45 | struct dl_list pending; /* struct gas_query_pending */ | |
46 | }; | |
47 | ||
48 | ||
49 | static void gas_query_tx_comeback_timeout(void *eloop_data, void *user_ctx); | |
50 | static void gas_query_timeout(void *eloop_data, void *user_ctx); | |
51 | ||
52 | ||
53 | struct gas_query * gas_query_init(struct wpa_supplicant *wpa_s) | |
54 | { | |
55 | struct gas_query *gas; | |
56 | ||
57 | gas = os_zalloc(sizeof(*gas)); | |
58 | if (gas == NULL) | |
59 | return NULL; | |
60 | ||
61 | gas->wpa_s = wpa_s; | |
62 | dl_list_init(&gas->pending); | |
63 | ||
64 | return gas; | |
65 | } | |
66 | ||
67 | ||
68 | static void gas_query_done(struct gas_query *gas, | |
69 | struct gas_query_pending *query, | |
70 | enum gas_query_result result) | |
71 | { | |
24f6497c JM |
72 | if (query->offchannel_tx_started) |
73 | offchannel_send_action_done(gas->wpa_s); | |
04ea7b79 JM |
74 | eloop_cancel_timeout(gas_query_tx_comeback_timeout, gas, query); |
75 | eloop_cancel_timeout(gas_query_timeout, gas, query); | |
76 | dl_list_del(&query->list); | |
77 | query->cb(query->ctx, query->addr, query->dialog_token, result, | |
78 | query->adv_proto, query->resp, query->status_code); | |
79 | wpabuf_free(query->adv_proto); | |
80 | wpabuf_free(query->resp); | |
81 | os_free(query); | |
82 | } | |
83 | ||
84 | ||
85 | void gas_query_deinit(struct gas_query *gas) | |
86 | { | |
87 | struct gas_query_pending *query, *next; | |
88 | ||
89 | if (gas == NULL) | |
90 | return; | |
91 | ||
92 | dl_list_for_each_safe(query, next, &gas->pending, | |
93 | struct gas_query_pending, list) | |
94 | gas_query_done(gas, query, GAS_QUERY_DELETED_AT_DEINIT); | |
95 | ||
96 | os_free(gas); | |
97 | } | |
98 | ||
99 | ||
100 | static struct gas_query_pending * | |
101 | gas_query_get_pending(struct gas_query *gas, const u8 *addr, u8 dialog_token) | |
102 | { | |
103 | struct gas_query_pending *q; | |
104 | dl_list_for_each(q, &gas->pending, struct gas_query_pending, list) { | |
105 | if (os_memcmp(q->addr, addr, ETH_ALEN) == 0 && | |
106 | q->dialog_token == dialog_token) | |
107 | return q; | |
108 | } | |
109 | return NULL; | |
110 | } | |
111 | ||
112 | ||
113 | static int gas_query_append(struct gas_query_pending *query, const u8 *data, | |
114 | size_t len) | |
115 | { | |
116 | if (wpabuf_resize(&query->resp, len) < 0) { | |
117 | wpa_printf(MSG_DEBUG, "GAS: No memory to store the response"); | |
118 | return -1; | |
119 | } | |
120 | wpabuf_put_data(query->resp, data, len); | |
121 | return 0; | |
122 | } | |
123 | ||
124 | ||
125 | static int gas_query_tx(struct gas_query *gas, struct gas_query_pending *query, | |
126 | struct wpabuf *req) | |
127 | { | |
24f6497c | 128 | int res; |
04ea7b79 JM |
129 | wpa_printf(MSG_DEBUG, "GAS: Send action frame to " MACSTR " len=%u " |
130 | "freq=%d", MAC2STR(query->addr), | |
131 | (unsigned int) wpabuf_len(req), query->freq); | |
24f6497c JM |
132 | res = offchannel_send_action(gas->wpa_s, query->freq, query->addr, |
133 | gas->wpa_s->own_addr, query->addr, | |
134 | wpabuf_head(req), wpabuf_len(req), 1000, | |
b106173a | 135 | NULL, 0); |
24f6497c JM |
136 | if (res == 0) |
137 | query->offchannel_tx_started = 1; | |
138 | return res; | |
04ea7b79 JM |
139 | } |
140 | ||
141 | ||
142 | static void gas_query_tx_comeback_req(struct gas_query *gas, | |
143 | struct gas_query_pending *query) | |
144 | { | |
145 | struct wpabuf *req; | |
146 | ||
147 | req = gas_build_comeback_req(query->dialog_token); | |
148 | if (req == NULL) { | |
149 | gas_query_done(gas, query, GAS_QUERY_INTERNAL_ERROR); | |
150 | return; | |
151 | } | |
152 | ||
153 | if (gas_query_tx(gas, query, req) < 0) { | |
154 | wpa_printf(MSG_DEBUG, "GAS: Failed to send Action frame to " | |
155 | MACSTR, MAC2STR(query->addr)); | |
156 | gas_query_done(gas, query, GAS_QUERY_INTERNAL_ERROR); | |
157 | } | |
158 | ||
159 | wpabuf_free(req); | |
160 | } | |
161 | ||
162 | ||
163 | static void gas_query_tx_comeback_timeout(void *eloop_data, void *user_ctx) | |
164 | { | |
165 | struct gas_query *gas = eloop_data; | |
166 | struct gas_query_pending *query = user_ctx; | |
167 | ||
168 | wpa_printf(MSG_DEBUG, "GAS: Comeback timeout for request to " MACSTR, | |
169 | MAC2STR(query->addr)); | |
170 | gas_query_tx_comeback_req(gas, query); | |
171 | } | |
172 | ||
173 | ||
174 | static void gas_query_tx_comeback_req_delay(struct gas_query *gas, | |
175 | struct gas_query_pending *query, | |
176 | u16 comeback_delay) | |
177 | { | |
178 | unsigned int secs, usecs; | |
179 | ||
180 | secs = (comeback_delay * 1024) / 1000000; | |
181 | usecs = comeback_delay * 1024 - secs * 1000000; | |
182 | wpa_printf(MSG_DEBUG, "GAS: Send comeback request to " MACSTR | |
183 | " in %u secs %u usecs", MAC2STR(query->addr), secs, usecs); | |
184 | eloop_cancel_timeout(gas_query_tx_comeback_timeout, gas, query); | |
185 | eloop_register_timeout(secs, usecs, gas_query_tx_comeback_timeout, | |
186 | gas, query); | |
187 | } | |
188 | ||
189 | ||
190 | static void gas_query_rx_initial(struct gas_query *gas, | |
191 | struct gas_query_pending *query, | |
192 | const u8 *adv_proto, const u8 *resp, | |
193 | size_t len, u16 comeback_delay) | |
194 | { | |
195 | wpa_printf(MSG_DEBUG, "GAS: Received initial response from " | |
196 | MACSTR " (dialog_token=%u comeback_delay=%u)", | |
197 | MAC2STR(query->addr), query->dialog_token, comeback_delay); | |
198 | ||
199 | query->adv_proto = wpabuf_alloc_copy(adv_proto, 2 + adv_proto[1]); | |
200 | if (query->adv_proto == NULL) { | |
201 | gas_query_done(gas, query, GAS_QUERY_INTERNAL_ERROR); | |
202 | return; | |
203 | } | |
204 | ||
205 | if (comeback_delay) { | |
206 | query->wait_comeback = 1; | |
207 | gas_query_tx_comeback_req_delay(gas, query, comeback_delay); | |
208 | return; | |
209 | } | |
210 | ||
211 | /* Query was completed without comeback mechanism */ | |
212 | if (gas_query_append(query, resp, len) < 0) { | |
213 | gas_query_done(gas, query, GAS_QUERY_INTERNAL_ERROR); | |
214 | return; | |
215 | } | |
216 | ||
217 | gas_query_done(gas, query, GAS_QUERY_SUCCESS); | |
218 | } | |
219 | ||
220 | ||
221 | static void gas_query_rx_comeback(struct gas_query *gas, | |
222 | struct gas_query_pending *query, | |
223 | const u8 *adv_proto, const u8 *resp, | |
224 | size_t len, u8 frag_id, u8 more_frags, | |
225 | u16 comeback_delay) | |
226 | { | |
227 | wpa_printf(MSG_DEBUG, "GAS: Received comeback response from " | |
228 | MACSTR " (dialog_token=%u frag_id=%u more_frags=%u " | |
229 | "comeback_delay=%u)", | |
230 | MAC2STR(query->addr), query->dialog_token, frag_id, | |
231 | more_frags, comeback_delay); | |
232 | ||
233 | if ((size_t) 2 + adv_proto[1] != wpabuf_len(query->adv_proto) || | |
234 | os_memcmp(adv_proto, wpabuf_head(query->adv_proto), | |
235 | wpabuf_len(query->adv_proto)) != 0) { | |
236 | wpa_printf(MSG_DEBUG, "GAS: Advertisement Protocol changed " | |
237 | "between initial and comeback response from " | |
238 | MACSTR, MAC2STR(query->addr)); | |
239 | gas_query_done(gas, query, GAS_QUERY_PEER_ERROR); | |
240 | return; | |
241 | } | |
242 | ||
243 | if (comeback_delay) { | |
244 | if (frag_id) { | |
245 | wpa_printf(MSG_DEBUG, "GAS: Invalid comeback response " | |
246 | "with non-zero frag_id and comeback_delay " | |
247 | "from " MACSTR, MAC2STR(query->addr)); | |
248 | gas_query_done(gas, query, GAS_QUERY_PEER_ERROR); | |
249 | return; | |
250 | } | |
251 | gas_query_tx_comeback_req_delay(gas, query, comeback_delay); | |
252 | return; | |
253 | } | |
254 | ||
255 | if (frag_id != query->next_frag_id) { | |
256 | wpa_printf(MSG_DEBUG, "GAS: Unexpected frag_id in response " | |
257 | "from " MACSTR, MAC2STR(query->addr)); | |
258 | gas_query_done(gas, query, GAS_QUERY_PEER_ERROR); | |
259 | return; | |
260 | } | |
261 | query->next_frag_id++; | |
262 | ||
263 | if (gas_query_append(query, resp, len) < 0) { | |
264 | gas_query_done(gas, query, GAS_QUERY_INTERNAL_ERROR); | |
265 | return; | |
266 | } | |
267 | ||
268 | if (more_frags) { | |
269 | gas_query_tx_comeback_req(gas, query); | |
270 | return; | |
271 | } | |
272 | ||
273 | gas_query_done(gas, query, GAS_QUERY_SUCCESS); | |
274 | } | |
275 | ||
276 | ||
277 | int gas_query_rx(struct gas_query *gas, const u8 *da, const u8 *sa, | |
278 | const u8 *bssid, const u8 *data, size_t len, int freq) | |
279 | { | |
280 | struct gas_query_pending *query; | |
281 | u8 action, dialog_token, frag_id = 0, more_frags = 0; | |
282 | u16 comeback_delay, resp_len; | |
283 | const u8 *pos, *adv_proto; | |
284 | ||
285 | if (gas == NULL || len < 4) | |
286 | return -1; | |
287 | ||
288 | pos = data; | |
289 | action = *pos++; | |
290 | dialog_token = *pos++; | |
291 | ||
292 | if (action != WLAN_PA_GAS_INITIAL_RESP && | |
293 | action != WLAN_PA_GAS_COMEBACK_RESP) | |
294 | return -1; /* Not a GAS response */ | |
295 | ||
296 | query = gas_query_get_pending(gas, sa, dialog_token); | |
297 | if (query == NULL) { | |
298 | wpa_printf(MSG_DEBUG, "GAS: No pending query found for " MACSTR | |
299 | " dialog token %u", MAC2STR(sa), dialog_token); | |
300 | return -1; | |
301 | } | |
302 | ||
303 | if (query->wait_comeback && action == WLAN_PA_GAS_INITIAL_RESP) { | |
304 | wpa_printf(MSG_DEBUG, "GAS: Unexpected initial response from " | |
305 | MACSTR " dialog token %u when waiting for comeback " | |
306 | "response", MAC2STR(sa), dialog_token); | |
307 | return 0; | |
308 | } | |
309 | ||
310 | if (!query->wait_comeback && action == WLAN_PA_GAS_COMEBACK_RESP) { | |
311 | wpa_printf(MSG_DEBUG, "GAS: Unexpected comeback response from " | |
312 | MACSTR " dialog token %u when waiting for initial " | |
313 | "response", MAC2STR(sa), dialog_token); | |
314 | return 0; | |
315 | } | |
316 | ||
317 | query->status_code = WPA_GET_LE16(pos); | |
318 | pos += 2; | |
319 | ||
320 | if (query->status_code != WLAN_STATUS_SUCCESS) { | |
321 | wpa_printf(MSG_DEBUG, "GAS: Query to " MACSTR " dialog token " | |
322 | "%u failed - status code %u", | |
323 | MAC2STR(sa), dialog_token, query->status_code); | |
324 | gas_query_done(gas, query, GAS_QUERY_FAILURE); | |
325 | return 0; | |
326 | } | |
327 | ||
328 | if (action == WLAN_PA_GAS_COMEBACK_RESP) { | |
329 | if (pos + 1 > data + len) | |
330 | return 0; | |
331 | frag_id = *pos & 0x7f; | |
332 | more_frags = (*pos & 0x80) >> 7; | |
333 | pos++; | |
334 | } | |
335 | ||
336 | /* Comeback Delay */ | |
337 | if (pos + 2 > data + len) | |
338 | return 0; | |
339 | comeback_delay = WPA_GET_LE16(pos); | |
340 | pos += 2; | |
341 | ||
342 | /* Advertisement Protocol element */ | |
343 | if (pos + 2 > data + len || pos + 2 + pos[1] > data + len) { | |
344 | wpa_printf(MSG_DEBUG, "GAS: No room for Advertisement " | |
345 | "Protocol element in the response from " MACSTR, | |
346 | MAC2STR(sa)); | |
347 | return 0; | |
348 | } | |
349 | ||
350 | if (*pos != WLAN_EID_ADV_PROTO) { | |
351 | wpa_printf(MSG_DEBUG, "GAS: Unexpected Advertisement " | |
352 | "Protocol element ID %u in response from " MACSTR, | |
353 | *pos, MAC2STR(sa)); | |
354 | return 0; | |
355 | } | |
356 | ||
357 | adv_proto = pos; | |
358 | pos += 2 + pos[1]; | |
359 | ||
360 | /* Query Response Length */ | |
361 | if (pos + 2 > data + len) { | |
362 | wpa_printf(MSG_DEBUG, "GAS: No room for GAS Response Length"); | |
363 | return 0; | |
364 | } | |
365 | resp_len = WPA_GET_LE16(pos); | |
366 | pos += 2; | |
367 | ||
368 | if (pos + resp_len > data + len) { | |
369 | wpa_printf(MSG_DEBUG, "GAS: Truncated Query Response in " | |
370 | "response from " MACSTR, MAC2STR(sa)); | |
371 | return 0; | |
372 | } | |
373 | ||
374 | if (pos + resp_len < data + len) { | |
375 | wpa_printf(MSG_DEBUG, "GAS: Ignore %u octets of extra data " | |
376 | "after Query Response from " MACSTR, | |
377 | (unsigned int) (data + len - pos - resp_len), | |
378 | MAC2STR(sa)); | |
379 | } | |
380 | ||
381 | if (action == WLAN_PA_GAS_COMEBACK_RESP) | |
382 | gas_query_rx_comeback(gas, query, adv_proto, pos, resp_len, | |
383 | frag_id, more_frags, comeback_delay); | |
384 | else | |
385 | gas_query_rx_initial(gas, query, adv_proto, pos, resp_len, | |
386 | comeback_delay); | |
387 | ||
388 | return 0; | |
389 | } | |
390 | ||
391 | ||
392 | static void gas_query_timeout(void *eloop_data, void *user_ctx) | |
393 | { | |
394 | struct gas_query *gas = eloop_data; | |
395 | struct gas_query_pending *query = user_ctx; | |
396 | ||
397 | wpa_printf(MSG_DEBUG, "GAS: No response received for query to " MACSTR, | |
398 | MAC2STR(query->addr)); | |
399 | gas_query_done(gas, query, GAS_QUERY_TIMEOUT); | |
400 | } | |
401 | ||
402 | ||
403 | static int gas_query_dialog_token_available(struct gas_query *gas, | |
404 | const u8 *dst, u8 dialog_token) | |
405 | { | |
406 | struct gas_query_pending *q; | |
407 | dl_list_for_each(q, &gas->pending, struct gas_query_pending, list) { | |
408 | if (os_memcmp(dst, q->addr, ETH_ALEN) == 0 && | |
409 | dialog_token == q->dialog_token) | |
410 | return 0; | |
411 | } | |
412 | ||
413 | return 1; | |
414 | } | |
415 | ||
416 | ||
417 | int gas_query_req(struct gas_query *gas, const u8 *dst, int freq, | |
418 | struct wpabuf *req, | |
419 | void (*cb)(void *ctx, const u8 *dst, u8 dialog_token, | |
420 | enum gas_query_result result, | |
421 | const struct wpabuf *adv_proto, | |
422 | const struct wpabuf *resp, u16 status_code), | |
423 | void *ctx) | |
424 | { | |
425 | struct gas_query_pending *query; | |
426 | int dialog_token; | |
427 | ||
428 | if (wpabuf_len(req) < 3) | |
429 | return -1; | |
430 | ||
431 | for (dialog_token = 0; dialog_token < 256; dialog_token++) { | |
432 | if (gas_query_dialog_token_available(gas, dst, dialog_token)) | |
433 | break; | |
434 | } | |
435 | if (dialog_token == 256) | |
436 | return -1; /* Too many pending queries */ | |
437 | ||
438 | query = os_zalloc(sizeof(*query)); | |
439 | if (query == NULL) | |
440 | return -1; | |
441 | ||
442 | os_memcpy(query->addr, dst, ETH_ALEN); | |
443 | query->dialog_token = dialog_token; | |
444 | query->freq = freq; | |
445 | query->cb = cb; | |
446 | query->ctx = ctx; | |
447 | dl_list_add(&gas->pending, &query->list); | |
448 | ||
449 | *(wpabuf_mhead_u8(req) + 2) = dialog_token; | |
450 | ||
451 | wpa_printf(MSG_DEBUG, "GAS: Starting request for " MACSTR | |
452 | " dialog_token %u", MAC2STR(dst), dialog_token); | |
453 | if (gas_query_tx(gas, query, req) < 0) { | |
454 | wpa_printf(MSG_DEBUG, "GAS: Failed to send Action frame to " | |
455 | MACSTR, MAC2STR(query->addr)); | |
456 | os_free(query); | |
457 | return -1; | |
458 | } | |
459 | ||
460 | eloop_register_timeout(GAS_QUERY_TIMEOUT, 0, gas_query_timeout, | |
461 | gas, query); | |
462 | ||
463 | return dialog_token; | |
464 | } | |
465 | ||
466 | ||
467 | void gas_query_cancel(struct gas_query *gas, const u8 *dst, u8 dialog_token) | |
468 | { | |
469 | struct gas_query_pending *query; | |
470 | ||
471 | query = gas_query_get_pending(gas, dst, dialog_token); | |
472 | if (query) | |
473 | gas_query_done(gas, query, GAS_QUERY_CANCELLED); | |
474 | ||
475 | } |