1 /*
2 * Generic advertisement service (GAS) query (hostapd)
3 * Copyright (c) 2009, Atheros Communications
4 * Copyright (c) 2011-2017, Qualcomm Atheros, Inc.
5 * Copyright (c) 2011-2014, Jouni Malinen <j@w1.fi>
6 *
7 * This software may be distributed under the terms of the BSD license.
8 * See README for more details.
9 */
10
11 #include "includes.h"
12
13 #include "common.h"
14 #include "utils/eloop.h"
15 #include "utils/list.h"
16 #include "common/ieee802_11_defs.h"
17 #include "common/gas.h"
18 #include "common/wpa_ctrl.h"
19 #include "hostapd.h"
20 #include "sta_info.h"
21 #include "ap_drv_ops.h"
22 #include "gas_query_ap.h"
23
24
25 /** GAS query timeout in seconds */
26 #define GAS_QUERY_TIMEOUT_PERIOD 2
27
28 /* GAS query wait-time / duration in ms */
29 #define GAS_QUERY_WAIT_TIME_INITIAL 1000
30 #define GAS_QUERY_WAIT_TIME_COMEBACK 150
31
32 /**
33 * struct gas_query_pending - Pending GAS query
34 */
35 struct gas_query_pending {
36 struct dl_list list;
37 struct gas_query_ap *gas;
38 u8 addr[ETH_ALEN];
39 u8 dialog_token;
40 u8 next_frag_id;
41 unsigned int wait_comeback:1;
42 unsigned int offchannel_tx_started:1;
43 unsigned int retry:1;
44 int freq;
45 u16 status_code;
46 struct wpabuf *req;
47 struct wpabuf *adv_proto;
48 struct wpabuf *resp;
49 struct os_reltime last_oper;
50 void (*cb)(void *ctx, const u8 *dst, u8 dialog_token,
51 enum gas_query_ap_result result,
52 const struct wpabuf *adv_proto,
53 const struct wpabuf *resp, u16 status_code);
54 void *ctx;
55 u8 sa[ETH_ALEN];
56 };
57
58 /**
59 * struct gas_query_ap - Internal GAS query data
60 */
61 struct gas_query_ap {
62 struct hostapd_data *hapd;
63 void *msg_ctx;
64 struct dl_list pending; /* struct gas_query_pending */
65 struct gas_query_pending *current;
66 };
67
68
69 static void gas_query_tx_comeback_timeout(void *eloop_data, void *user_ctx);
70 static void gas_query_timeout(void *eloop_data, void *user_ctx);
71 static void gas_query_rx_comeback_timeout(void *eloop_data, void *user_ctx);
72 static void gas_query_tx_initial_req(struct gas_query_ap *gas,
73 struct gas_query_pending *query);
74 static int gas_query_new_dialog_token(struct gas_query_ap *gas, const u8 *dst);
75
76
ms_from_time(struct os_reltime * last)77 static int ms_from_time(struct os_reltime *last)
78 {
79 struct os_reltime now, res;
80
81 os_get_reltime(&now);
82 os_reltime_sub(&now, last, &res);
83 return res.sec * 1000 + res.usec / 1000;
84 }
85
86
87 /**
88 * gas_query_ap_init - Initialize GAS query component
89 * @hapd: Pointer to hostapd data
90 * Returns: Pointer to GAS query data or %NULL on failure
91 */
gas_query_ap_init(struct hostapd_data * hapd,void * msg_ctx)92 struct gas_query_ap * gas_query_ap_init(struct hostapd_data *hapd,
93 void *msg_ctx)
94 {
95 struct gas_query_ap *gas;
96
97 gas = os_zalloc(sizeof(*gas));
98 if (!gas)
99 return NULL;
100
101 gas->hapd = hapd;
102 gas->msg_ctx = msg_ctx;
103 dl_list_init(&gas->pending);
104
105 return gas;
106 }
107
108
gas_result_txt(enum gas_query_ap_result result)109 static const char * gas_result_txt(enum gas_query_ap_result result)
110 {
111 switch (result) {
112 case GAS_QUERY_AP_SUCCESS:
113 return "SUCCESS";
114 case GAS_QUERY_AP_FAILURE:
115 return "FAILURE";
116 case GAS_QUERY_AP_TIMEOUT:
117 return "TIMEOUT";
118 case GAS_QUERY_AP_PEER_ERROR:
119 return "PEER_ERROR";
120 case GAS_QUERY_AP_INTERNAL_ERROR:
121 return "INTERNAL_ERROR";
122 case GAS_QUERY_AP_DELETED_AT_DEINIT:
123 return "DELETED_AT_DEINIT";
124 }
125
126 return "N/A";
127 }
128
129
gas_query_free(struct gas_query_pending * query,int del_list)130 static void gas_query_free(struct gas_query_pending *query, int del_list)
131 {
132 if (del_list)
133 dl_list_del(&query->list);
134
135 wpabuf_free(query->req);
136 wpabuf_free(query->adv_proto);
137 wpabuf_free(query->resp);
138 os_free(query);
139 }
140
141
gas_query_done(struct gas_query_ap * gas,struct gas_query_pending * query,enum gas_query_ap_result result)142 static void gas_query_done(struct gas_query_ap *gas,
143 struct gas_query_pending *query,
144 enum gas_query_ap_result result)
145 {
146 wpa_msg(gas->msg_ctx, MSG_INFO, GAS_QUERY_DONE "addr=" MACSTR
147 " dialog_token=%u freq=%d status_code=%u result=%s",
148 MAC2STR(query->addr), query->dialog_token, query->freq,
149 query->status_code, gas_result_txt(result));
150 if (gas->current == query)
151 gas->current = NULL;
152 eloop_cancel_timeout(gas_query_tx_comeback_timeout, gas, query);
153 eloop_cancel_timeout(gas_query_timeout, gas, query);
154 eloop_cancel_timeout(gas_query_rx_comeback_timeout, gas, query);
155 dl_list_del(&query->list);
156 query->cb(query->ctx, query->addr, query->dialog_token, result,
157 query->adv_proto, query->resp, query->status_code);
158 gas_query_free(query, 0);
159 }
160
161
162 /**
163 * gas_query_ap_deinit - Deinitialize GAS query component
164 * @gas: GAS query data from gas_query_init()
165 */
gas_query_ap_deinit(struct gas_query_ap * gas)166 void gas_query_ap_deinit(struct gas_query_ap *gas)
167 {
168 struct gas_query_pending *query, *next;
169
170 if (gas == NULL)
171 return;
172
173 dl_list_for_each_safe(query, next, &gas->pending,
174 struct gas_query_pending, list)
175 gas_query_done(gas, query, GAS_QUERY_AP_DELETED_AT_DEINIT);
176
177 os_free(gas);
178 }
179
180
181 static struct gas_query_pending *
gas_query_get_pending(struct gas_query_ap * gas,const u8 * addr,u8 dialog_token)182 gas_query_get_pending(struct gas_query_ap *gas, const u8 *addr, u8 dialog_token)
183 {
184 struct gas_query_pending *q;
185 dl_list_for_each(q, &gas->pending, struct gas_query_pending, list) {
186 if (os_memcmp(q->addr, addr, ETH_ALEN) == 0 &&
187 q->dialog_token == dialog_token)
188 return q;
189 }
190 return NULL;
191 }
192
193
gas_query_append(struct gas_query_pending * query,const u8 * data,size_t len)194 static int gas_query_append(struct gas_query_pending *query, const u8 *data,
195 size_t len)
196 {
197 if (wpabuf_resize(&query->resp, len) < 0) {
198 wpa_printf(MSG_DEBUG, "GAS: No memory to store the response");
199 return -1;
200 }
201 wpabuf_put_data(query->resp, data, len);
202 return 0;
203 }
204
205
gas_query_ap_tx_status(struct gas_query_ap * gas,const u8 * dst,const u8 * data,size_t data_len,int ok)206 void gas_query_ap_tx_status(struct gas_query_ap *gas, const u8 *dst,
207 const u8 *data, size_t data_len, int ok)
208 {
209 struct gas_query_pending *query;
210 int dur;
211
212 if (!gas || !gas->current) {
213 wpa_printf(MSG_DEBUG, "GAS: Unexpected TX status: dst=" MACSTR
214 " ok=%d - no query in progress", MAC2STR(dst), ok);
215 return;
216 }
217
218 query = gas->current;
219
220 dur = ms_from_time(&query->last_oper);
221 wpa_printf(MSG_DEBUG, "GAS: TX status: dst=" MACSTR
222 " ok=%d query=%p dialog_token=%u dur=%d ms",
223 MAC2STR(dst), ok, query, query->dialog_token, dur);
224 if (os_memcmp(dst, query->addr, ETH_ALEN) != 0) {
225 wpa_printf(MSG_DEBUG, "GAS: TX status for unexpected destination");
226 return;
227 }
228 os_get_reltime(&query->last_oper);
229
230 eloop_cancel_timeout(gas_query_timeout, gas, query);
231 if (!ok) {
232 wpa_printf(MSG_DEBUG, "GAS: No ACK to GAS request");
233 eloop_register_timeout(0, 250000, gas_query_timeout,
234 gas, query);
235 } else {
236 eloop_register_timeout(GAS_QUERY_TIMEOUT_PERIOD, 0,
237 gas_query_timeout, gas, query);
238 }
239 if (query->wait_comeback && !query->retry) {
240 eloop_cancel_timeout(gas_query_rx_comeback_timeout,
241 gas, query);
242 eloop_register_timeout(
243 0, (GAS_QUERY_WAIT_TIME_COMEBACK + 10) * 1000,
244 gas_query_rx_comeback_timeout, gas, query);
245 }
246 }
247
248
pmf_in_use(struct hostapd_data * hapd,const u8 * addr)249 static int pmf_in_use(struct hostapd_data *hapd, const u8 *addr)
250 {
251 struct sta_info *sta;
252
253 sta = ap_get_sta(hapd, addr);
254 return sta && (sta->flags & WLAN_STA_MFP);
255 }
256
257
gas_query_tx(struct gas_query_ap * gas,struct gas_query_pending * query,struct wpabuf * req,unsigned int wait_time)258 static int gas_query_tx(struct gas_query_ap *gas,
259 struct gas_query_pending *query,
260 struct wpabuf *req, unsigned int wait_time)
261 {
262 int res, prot = pmf_in_use(gas->hapd, query->addr);
263
264 wpa_printf(MSG_DEBUG, "GAS: Send action frame to " MACSTR " len=%u "
265 "freq=%d prot=%d using src addr " MACSTR,
266 MAC2STR(query->addr), (unsigned int) wpabuf_len(req),
267 query->freq, prot, MAC2STR(query->sa));
268 if (prot) {
269 u8 *categ = wpabuf_mhead_u8(req);
270 *categ = WLAN_ACTION_PROTECTED_DUAL;
271 }
272 os_get_reltime(&query->last_oper);
273 res = hostapd_drv_send_action(gas->hapd, query->freq, wait_time,
274 query->addr, wpabuf_head(req),
275 wpabuf_len(req));
276 return res;
277 }
278
279
gas_query_tx_comeback_req(struct gas_query_ap * gas,struct gas_query_pending * query)280 static void gas_query_tx_comeback_req(struct gas_query_ap *gas,
281 struct gas_query_pending *query)
282 {
283 struct wpabuf *req;
284 unsigned int wait_time;
285
286 req = gas_build_comeback_req(query->dialog_token);
287 if (req == NULL) {
288 gas_query_done(gas, query, GAS_QUERY_AP_INTERNAL_ERROR);
289 return;
290 }
291
292 wait_time = (query->retry || !query->offchannel_tx_started) ?
293 GAS_QUERY_WAIT_TIME_INITIAL : GAS_QUERY_WAIT_TIME_COMEBACK;
294
295 if (gas_query_tx(gas, query, req, wait_time) < 0) {
296 wpa_printf(MSG_DEBUG, "GAS: Failed to send Action frame to "
297 MACSTR, MAC2STR(query->addr));
298 gas_query_done(gas, query, GAS_QUERY_AP_INTERNAL_ERROR);
299 }
300
301 wpabuf_free(req);
302 }
303
304
gas_query_rx_comeback_timeout(void * eloop_data,void * user_ctx)305 static void gas_query_rx_comeback_timeout(void *eloop_data, void *user_ctx)
306 {
307 struct gas_query_ap *gas = eloop_data;
308 struct gas_query_pending *query = user_ctx;
309 int dialog_token;
310
311 wpa_printf(MSG_DEBUG,
312 "GAS: No response to comeback request received (retry=%u)",
313 query->retry);
314 if (gas->current != query || query->retry)
315 return;
316 dialog_token = gas_query_new_dialog_token(gas, query->addr);
317 if (dialog_token < 0)
318 return;
319 wpa_printf(MSG_DEBUG,
320 "GAS: Retry GAS query due to comeback response timeout");
321 query->retry = 1;
322 query->dialog_token = dialog_token;
323 *(wpabuf_mhead_u8(query->req) + 2) = dialog_token;
324 query->wait_comeback = 0;
325 query->next_frag_id = 0;
326 wpabuf_free(query->adv_proto);
327 query->adv_proto = NULL;
328 eloop_cancel_timeout(gas_query_tx_comeback_timeout, gas, query);
329 eloop_cancel_timeout(gas_query_timeout, gas, query);
330 gas_query_tx_initial_req(gas, query);
331 }
332
333
gas_query_tx_comeback_timeout(void * eloop_data,void * user_ctx)334 static void gas_query_tx_comeback_timeout(void *eloop_data, void *user_ctx)
335 {
336 struct gas_query_ap *gas = eloop_data;
337 struct gas_query_pending *query = user_ctx;
338
339 wpa_printf(MSG_DEBUG, "GAS: Comeback timeout for request to " MACSTR,
340 MAC2STR(query->addr));
341 gas_query_tx_comeback_req(gas, query);
342 }
343
344
gas_query_tx_comeback_req_delay(struct gas_query_ap * gas,struct gas_query_pending * query,u16 comeback_delay)345 static void gas_query_tx_comeback_req_delay(struct gas_query_ap *gas,
346 struct gas_query_pending *query,
347 u16 comeback_delay)
348 {
349 unsigned int secs, usecs;
350
351 secs = (comeback_delay * 1024) / 1000000;
352 usecs = comeback_delay * 1024 - secs * 1000000;
353 wpa_printf(MSG_DEBUG, "GAS: Send comeback request to " MACSTR
354 " in %u secs %u usecs", MAC2STR(query->addr), secs, usecs);
355 eloop_cancel_timeout(gas_query_tx_comeback_timeout, gas, query);
356 eloop_register_timeout(secs, usecs, gas_query_tx_comeback_timeout,
357 gas, query);
358 }
359
360
gas_query_rx_initial(struct gas_query_ap * gas,struct gas_query_pending * query,const u8 * adv_proto,const u8 * resp,size_t len,u16 comeback_delay)361 static void gas_query_rx_initial(struct gas_query_ap *gas,
362 struct gas_query_pending *query,
363 const u8 *adv_proto, const u8 *resp,
364 size_t len, u16 comeback_delay)
365 {
366 wpa_printf(MSG_DEBUG, "GAS: Received initial response from "
367 MACSTR " (dialog_token=%u comeback_delay=%u)",
368 MAC2STR(query->addr), query->dialog_token, comeback_delay);
369
370 query->adv_proto = wpabuf_alloc_copy(adv_proto, 2 + adv_proto[1]);
371 if (query->adv_proto == NULL) {
372 gas_query_done(gas, query, GAS_QUERY_AP_INTERNAL_ERROR);
373 return;
374 }
375
376 if (comeback_delay) {
377 eloop_cancel_timeout(gas_query_timeout, gas, query);
378 query->wait_comeback = 1;
379 gas_query_tx_comeback_req_delay(gas, query, comeback_delay);
380 return;
381 }
382
383 /* Query was completed without comeback mechanism */
384 if (gas_query_append(query, resp, len) < 0) {
385 gas_query_done(gas, query, GAS_QUERY_AP_INTERNAL_ERROR);
386 return;
387 }
388
389 gas_query_done(gas, query, GAS_QUERY_AP_SUCCESS);
390 }
391
392
gas_query_rx_comeback(struct gas_query_ap * gas,struct gas_query_pending * query,const u8 * adv_proto,const u8 * resp,size_t len,u8 frag_id,u8 more_frags,u16 comeback_delay)393 static void gas_query_rx_comeback(struct gas_query_ap *gas,
394 struct gas_query_pending *query,
395 const u8 *adv_proto, const u8 *resp,
396 size_t len, u8 frag_id, u8 more_frags,
397 u16 comeback_delay)
398 {
399 wpa_printf(MSG_DEBUG, "GAS: Received comeback response from "
400 MACSTR " (dialog_token=%u frag_id=%u more_frags=%u "
401 "comeback_delay=%u)",
402 MAC2STR(query->addr), query->dialog_token, frag_id,
403 more_frags, comeback_delay);
404 eloop_cancel_timeout(gas_query_rx_comeback_timeout, gas, query);
405
406 if ((size_t) 2 + adv_proto[1] != wpabuf_len(query->adv_proto) ||
407 os_memcmp(adv_proto, wpabuf_head(query->adv_proto),
408 wpabuf_len(query->adv_proto)) != 0) {
409 wpa_printf(MSG_DEBUG, "GAS: Advertisement Protocol changed "
410 "between initial and comeback response from "
411 MACSTR, MAC2STR(query->addr));
412 gas_query_done(gas, query, GAS_QUERY_AP_PEER_ERROR);
413 return;
414 }
415
416 if (comeback_delay) {
417 if (frag_id) {
418 wpa_printf(MSG_DEBUG, "GAS: Invalid comeback response "
419 "with non-zero frag_id and comeback_delay "
420 "from " MACSTR, MAC2STR(query->addr));
421 gas_query_done(gas, query, GAS_QUERY_AP_PEER_ERROR);
422 return;
423 }
424 gas_query_tx_comeback_req_delay(gas, query, comeback_delay);
425 return;
426 }
427
428 if (frag_id != query->next_frag_id) {
429 wpa_printf(MSG_DEBUG, "GAS: Unexpected frag_id in response "
430 "from " MACSTR, MAC2STR(query->addr));
431 if (frag_id + 1 == query->next_frag_id) {
432 wpa_printf(MSG_DEBUG, "GAS: Drop frame as possible "
433 "retry of previous fragment");
434 return;
435 }
436 gas_query_done(gas, query, GAS_QUERY_AP_PEER_ERROR);
437 return;
438 }
439 query->next_frag_id++;
440
441 if (gas_query_append(query, resp, len) < 0) {
442 gas_query_done(gas, query, GAS_QUERY_AP_INTERNAL_ERROR);
443 return;
444 }
445
446 if (more_frags) {
447 gas_query_tx_comeback_req(gas, query);
448 return;
449 }
450
451 gas_query_done(gas, query, GAS_QUERY_AP_SUCCESS);
452 }
453
454
455 /**
456 * gas_query_ap_rx - Indicate reception of a Public Action or Protected Dual
457 * frame
458 * @gas: GAS query data from gas_query_init()
459 * @sa: Source MAC address of the Action frame
460 * @categ: Category of the Action frame
461 * @data: Payload of the Action frame
462 * @len: Length of @data
463 * @freq: Frequency (in MHz) on which the frame was received
464 * Returns: 0 if the Public Action frame was a GAS frame or -1 if not
465 */
gas_query_ap_rx(struct gas_query_ap * gas,const u8 * sa,u8 categ,const u8 * data,size_t len,int freq)466 int gas_query_ap_rx(struct gas_query_ap *gas, const u8 *sa, u8 categ,
467 const u8 *data, size_t len, int freq)
468 {
469 struct gas_query_pending *query;
470 u8 action, dialog_token, frag_id = 0, more_frags = 0;
471 u16 comeback_delay, resp_len;
472 const u8 *pos, *adv_proto;
473 int prot, pmf;
474 unsigned int left;
475
476 if (!gas || len < 4)
477 return -1;
478
479 pos = data;
480 action = *pos++;
481 dialog_token = *pos++;
482
483 if (action != WLAN_PA_GAS_INITIAL_RESP &&
484 action != WLAN_PA_GAS_COMEBACK_RESP)
485 return -1; /* Not a GAS response */
486
487 prot = categ == WLAN_ACTION_PROTECTED_DUAL;
488 pmf = pmf_in_use(gas->hapd, sa);
489 if (prot && !pmf) {
490 wpa_printf(MSG_DEBUG, "GAS: Drop unexpected protected GAS frame when PMF is disabled");
491 return 0;
492 }
493 if (!prot && pmf) {
494 wpa_printf(MSG_DEBUG, "GAS: Drop unexpected unprotected GAS frame when PMF is enabled");
495 return 0;
496 }
497
498 query = gas_query_get_pending(gas, sa, dialog_token);
499 if (query == NULL) {
500 wpa_printf(MSG_DEBUG, "GAS: No pending query found for " MACSTR
501 " dialog token %u", MAC2STR(sa), dialog_token);
502 return -1;
503 }
504
505 wpa_printf(MSG_DEBUG, "GAS: Response in %d ms from " MACSTR,
506 ms_from_time(&query->last_oper), MAC2STR(sa));
507
508 if (query->wait_comeback && action == WLAN_PA_GAS_INITIAL_RESP) {
509 wpa_printf(MSG_DEBUG, "GAS: Unexpected initial response from "
510 MACSTR " dialog token %u when waiting for comeback "
511 "response", MAC2STR(sa), dialog_token);
512 return 0;
513 }
514
515 if (!query->wait_comeback && action == WLAN_PA_GAS_COMEBACK_RESP) {
516 wpa_printf(MSG_DEBUG, "GAS: Unexpected comeback response from "
517 MACSTR " dialog token %u when waiting for initial "
518 "response", MAC2STR(sa), dialog_token);
519 return 0;
520 }
521
522 query->status_code = WPA_GET_LE16(pos);
523 pos += 2;
524
525 if (query->status_code == WLAN_STATUS_QUERY_RESP_OUTSTANDING &&
526 action == WLAN_PA_GAS_COMEBACK_RESP) {
527 wpa_printf(MSG_DEBUG, "GAS: Allow non-zero status for outstanding comeback response");
528 } else if (query->status_code != WLAN_STATUS_SUCCESS) {
529 wpa_printf(MSG_DEBUG, "GAS: Query to " MACSTR " dialog token "
530 "%u failed - status code %u",
531 MAC2STR(sa), dialog_token, query->status_code);
532 gas_query_done(gas, query, GAS_QUERY_AP_FAILURE);
533 return 0;
534 }
535
536 if (action == WLAN_PA_GAS_COMEBACK_RESP) {
537 if (pos + 1 > data + len)
538 return 0;
539 frag_id = *pos & 0x7f;
540 more_frags = (*pos & 0x80) >> 7;
541 pos++;
542 }
543
544 /* Comeback Delay */
545 if (pos + 2 > data + len)
546 return 0;
547 comeback_delay = WPA_GET_LE16(pos);
548 pos += 2;
549
550 /* Advertisement Protocol element */
551 if (pos + 2 > data + len || pos + 2 + pos[1] > data + len) {
552 wpa_printf(MSG_DEBUG, "GAS: No room for Advertisement "
553 "Protocol element in the response from " MACSTR,
554 MAC2STR(sa));
555 return 0;
556 }
557
558 if (*pos != WLAN_EID_ADV_PROTO) {
559 wpa_printf(MSG_DEBUG, "GAS: Unexpected Advertisement "
560 "Protocol element ID %u in response from " MACSTR,
561 *pos, MAC2STR(sa));
562 return 0;
563 }
564
565 adv_proto = pos;
566 pos += 2 + pos[1];
567
568 /* Query Response Length */
569 if (pos + 2 > data + len) {
570 wpa_printf(MSG_DEBUG, "GAS: No room for GAS Response Length");
571 return 0;
572 }
573 resp_len = WPA_GET_LE16(pos);
574 pos += 2;
575
576 left = data + len - pos;
577 if (resp_len > left) {
578 wpa_printf(MSG_DEBUG, "GAS: Truncated Query Response in "
579 "response from " MACSTR, MAC2STR(sa));
580 return 0;
581 }
582
583 if (resp_len < left) {
584 wpa_printf(MSG_DEBUG, "GAS: Ignore %u octets of extra data "
585 "after Query Response from " MACSTR,
586 left - resp_len, MAC2STR(sa));
587 }
588
589 if (action == WLAN_PA_GAS_COMEBACK_RESP)
590 gas_query_rx_comeback(gas, query, adv_proto, pos, resp_len,
591 frag_id, more_frags, comeback_delay);
592 else
593 gas_query_rx_initial(gas, query, adv_proto, pos, resp_len,
594 comeback_delay);
595
596 return 0;
597 }
598
599
gas_query_timeout(void * eloop_data,void * user_ctx)600 static void gas_query_timeout(void *eloop_data, void *user_ctx)
601 {
602 struct gas_query_ap *gas = eloop_data;
603 struct gas_query_pending *query = user_ctx;
604
605 wpa_printf(MSG_DEBUG, "GAS: No response received for query to " MACSTR
606 " dialog token %u",
607 MAC2STR(query->addr), query->dialog_token);
608 gas_query_done(gas, query, GAS_QUERY_AP_TIMEOUT);
609 }
610
611
gas_query_dialog_token_available(struct gas_query_ap * gas,const u8 * dst,u8 dialog_token)612 static int gas_query_dialog_token_available(struct gas_query_ap *gas,
613 const u8 *dst, u8 dialog_token)
614 {
615 struct gas_query_pending *q;
616 dl_list_for_each(q, &gas->pending, struct gas_query_pending, list) {
617 if (os_memcmp(dst, q->addr, ETH_ALEN) == 0 &&
618 dialog_token == q->dialog_token)
619 return 0;
620 }
621
622 return 1;
623 }
624
625
gas_query_tx_initial_req(struct gas_query_ap * gas,struct gas_query_pending * query)626 static void gas_query_tx_initial_req(struct gas_query_ap *gas,
627 struct gas_query_pending *query)
628 {
629 if (gas_query_tx(gas, query, query->req,
630 GAS_QUERY_WAIT_TIME_INITIAL) < 0) {
631 wpa_printf(MSG_DEBUG, "GAS: Failed to send Action frame to "
632 MACSTR, MAC2STR(query->addr));
633 gas_query_done(gas, query, GAS_QUERY_AP_INTERNAL_ERROR);
634 return;
635 }
636 gas->current = query;
637
638 wpa_printf(MSG_DEBUG, "GAS: Starting query timeout for dialog token %u",
639 query->dialog_token);
640 eloop_register_timeout(GAS_QUERY_TIMEOUT_PERIOD, 0,
641 gas_query_timeout, gas, query);
642 }
643
644
gas_query_new_dialog_token(struct gas_query_ap * gas,const u8 * dst)645 static int gas_query_new_dialog_token(struct gas_query_ap *gas, const u8 *dst)
646 {
647 static int next_start = 0;
648 int dialog_token;
649
650 for (dialog_token = 0; dialog_token < 256; dialog_token++) {
651 if (gas_query_dialog_token_available(
652 gas, dst, (next_start + dialog_token) % 256))
653 break;
654 }
655 if (dialog_token == 256)
656 return -1; /* Too many pending queries */
657 dialog_token = (next_start + dialog_token) % 256;
658 next_start = (dialog_token + 1) % 256;
659 return dialog_token;
660 }
661
662
663 /**
664 * gas_query_ap_req - Request a GAS query
665 * @gas: GAS query data from gas_query_init()
666 * @dst: Destination MAC address for the query
667 * @freq: Frequency (in MHz) for the channel on which to send the query
668 * @req: GAS query payload (to be freed by gas_query module in case of success
669 * return)
670 * @cb: Callback function for reporting GAS query result and response
671 * @ctx: Context pointer to use with the @cb call
672 * Returns: dialog token (>= 0) on success or -1 on failure
673 */
gas_query_ap_req(struct gas_query_ap * gas,const u8 * dst,int freq,struct wpabuf * req,void (* cb)(void * ctx,const u8 * dst,u8 dialog_token,enum gas_query_ap_result result,const struct wpabuf * adv_proto,const struct wpabuf * resp,u16 status_code),void * ctx)674 int gas_query_ap_req(struct gas_query_ap *gas, const u8 *dst, int freq,
675 struct wpabuf *req,
676 void (*cb)(void *ctx, const u8 *dst, u8 dialog_token,
677 enum gas_query_ap_result result,
678 const struct wpabuf *adv_proto,
679 const struct wpabuf *resp, u16 status_code),
680 void *ctx)
681 {
682 struct gas_query_pending *query;
683 int dialog_token;
684
685 if (!gas || wpabuf_len(req) < 3)
686 return -1;
687
688 dialog_token = gas_query_new_dialog_token(gas, dst);
689 if (dialog_token < 0)
690 return -1;
691
692 query = os_zalloc(sizeof(*query));
693 if (query == NULL)
694 return -1;
695
696 query->gas = gas;
697 os_memcpy(query->addr, dst, ETH_ALEN);
698 query->dialog_token = dialog_token;
699 query->freq = freq;
700 query->cb = cb;
701 query->ctx = ctx;
702 query->req = req;
703 dl_list_add(&gas->pending, &query->list);
704
705 *(wpabuf_mhead_u8(req) + 2) = dialog_token;
706
707 wpa_msg(gas->msg_ctx, MSG_INFO, GAS_QUERY_START "addr=" MACSTR
708 " dialog_token=%u freq=%d",
709 MAC2STR(query->addr), query->dialog_token, query->freq);
710
711 gas_query_tx_initial_req(gas, query);
712
713 return dialog_token;
714 }
715