1/*
2 * Generic advertisement service (GAS) query
3 * Copyright (c) 2009, Atheros Communications
4 * Copyright (c) 2011-2014, 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 "common/ieee802_11_defs.h"
16#include "common/gas.h"
17#include "common/wpa_ctrl.h"
18#include "rsn_supp/wpa.h"
19#include "wpa_supplicant_i.h"
20#include "driver_i.h"
21#include "offchannel.h"
22#include "gas_query.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 */
35struct gas_query_pending {
36	struct dl_list list;
37	struct gas_query *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_result result,
52		   const struct wpabuf *adv_proto,
53		   const struct wpabuf *resp, u16 status_code);
54	void *ctx;
55};
56
57/**
58 * struct gas_query - Internal GAS query data
59 */
60struct gas_query {
61	struct wpa_supplicant *wpa_s;
62	struct dl_list pending; /* struct gas_query_pending */
63	struct gas_query_pending *current;
64	struct wpa_radio_work *work;
65};
66
67
68static void gas_query_tx_comeback_timeout(void *eloop_data, void *user_ctx);
69static void gas_query_timeout(void *eloop_data, void *user_ctx);
70static void gas_query_rx_comeback_timeout(void *eloop_data, void *user_ctx);
71static void gas_query_tx_initial_req(struct gas_query *gas,
72				     struct gas_query_pending *query);
73static int gas_query_new_dialog_token(struct gas_query *gas, const u8 *dst);
74
75
76static int ms_from_time(struct os_reltime *last)
77{
78	struct os_reltime now, res;
79
80	os_get_reltime(&now);
81	os_reltime_sub(&now, last, &res);
82	return res.sec * 1000 + res.usec / 1000;
83}
84
85
86/**
87 * gas_query_init - Initialize GAS query component
88 * @wpa_s: Pointer to wpa_supplicant data
89 * Returns: Pointer to GAS query data or %NULL on failure
90 */
91struct gas_query * gas_query_init(struct wpa_supplicant *wpa_s)
92{
93	struct gas_query *gas;
94
95	gas = os_zalloc(sizeof(*gas));
96	if (gas == NULL)
97		return NULL;
98
99	gas->wpa_s = wpa_s;
100	dl_list_init(&gas->pending);
101
102	return gas;
103}
104
105
106static const char * gas_result_txt(enum gas_query_result result)
107{
108	switch (result) {
109	case GAS_QUERY_SUCCESS:
110		return "SUCCESS";
111	case GAS_QUERY_FAILURE:
112		return "FAILURE";
113	case GAS_QUERY_TIMEOUT:
114		return "TIMEOUT";
115	case GAS_QUERY_PEER_ERROR:
116		return "PEER_ERROR";
117	case GAS_QUERY_INTERNAL_ERROR:
118		return "INTERNAL_ERROR";
119	case GAS_QUERY_CANCELLED:
120		return "CANCELLED";
121	case GAS_QUERY_DELETED_AT_DEINIT:
122		return "DELETED_AT_DEINIT";
123	}
124
125	return "N/A";
126}
127
128
129static void gas_query_free(struct gas_query_pending *query, int del_list)
130{
131	struct gas_query *gas = query->gas;
132
133	if (del_list)
134		dl_list_del(&query->list);
135
136	if (gas->work && gas->work->ctx == query) {
137		radio_work_done(gas->work);
138		gas->work = NULL;
139	}
140
141	wpabuf_free(query->req);
142	wpabuf_free(query->adv_proto);
143	wpabuf_free(query->resp);
144	os_free(query);
145}
146
147
148static void gas_query_done(struct gas_query *gas,
149			   struct gas_query_pending *query,
150			   enum gas_query_result result)
151{
152	wpa_msg(gas->wpa_s, MSG_INFO, GAS_QUERY_DONE "addr=" MACSTR
153		" dialog_token=%u freq=%d status_code=%u result=%s",
154		MAC2STR(query->addr), query->dialog_token, query->freq,
155		query->status_code, gas_result_txt(result));
156	if (gas->current == query)
157		gas->current = NULL;
158	if (query->offchannel_tx_started)
159		offchannel_send_action_done(gas->wpa_s);
160	eloop_cancel_timeout(gas_query_tx_comeback_timeout, gas, query);
161	eloop_cancel_timeout(gas_query_timeout, gas, query);
162	eloop_cancel_timeout(gas_query_rx_comeback_timeout, gas, query);
163	dl_list_del(&query->list);
164	query->cb(query->ctx, query->addr, query->dialog_token, result,
165		  query->adv_proto, query->resp, query->status_code);
166	gas_query_free(query, 0);
167}
168
169
170/**
171 * gas_query_deinit - Deinitialize GAS query component
172 * @gas: GAS query data from gas_query_init()
173 */
174void gas_query_deinit(struct gas_query *gas)
175{
176	struct gas_query_pending *query, *next;
177
178	if (gas == NULL)
179		return;
180
181	dl_list_for_each_safe(query, next, &gas->pending,
182			      struct gas_query_pending, list)
183		gas_query_done(gas, query, GAS_QUERY_DELETED_AT_DEINIT);
184
185	os_free(gas);
186}
187
188
189static struct gas_query_pending *
190gas_query_get_pending(struct gas_query *gas, const u8 *addr, u8 dialog_token)
191{
192	struct gas_query_pending *q;
193	dl_list_for_each(q, &gas->pending, struct gas_query_pending, list) {
194		if (os_memcmp(q->addr, addr, ETH_ALEN) == 0 &&
195		    q->dialog_token == dialog_token)
196			return q;
197	}
198	return NULL;
199}
200
201
202static int gas_query_append(struct gas_query_pending *query, const u8 *data,
203			    size_t len)
204{
205	if (wpabuf_resize(&query->resp, len) < 0) {
206		wpa_printf(MSG_DEBUG, "GAS: No memory to store the response");
207		return -1;
208	}
209	wpabuf_put_data(query->resp, data, len);
210	return 0;
211}
212
213
214static void gas_query_tx_status(struct wpa_supplicant *wpa_s,
215				unsigned int freq, const u8 *dst,
216				const u8 *src, const u8 *bssid,
217				const u8 *data, size_t data_len,
218				enum offchannel_send_action_result result)
219{
220	struct gas_query_pending *query;
221	struct gas_query *gas = wpa_s->gas;
222	int dur;
223
224	if (gas->current == NULL) {
225		wpa_printf(MSG_DEBUG, "GAS: Unexpected TX status: freq=%u dst="
226			   MACSTR " result=%d - no query in progress",
227			   freq, MAC2STR(dst), result);
228		return;
229	}
230
231	query = gas->current;
232
233	dur = ms_from_time(&query->last_oper);
234	wpa_printf(MSG_DEBUG, "GAS: TX status: freq=%u dst=" MACSTR
235		   " result=%d query=%p dialog_token=%u dur=%d ms",
236		   freq, MAC2STR(dst), result, query, query->dialog_token, dur);
237	if (os_memcmp(dst, query->addr, ETH_ALEN) != 0) {
238		wpa_printf(MSG_DEBUG, "GAS: TX status for unexpected destination");
239		return;
240	}
241	os_get_reltime(&query->last_oper);
242
243	if (result == OFFCHANNEL_SEND_ACTION_SUCCESS) {
244		eloop_cancel_timeout(gas_query_timeout, gas, query);
245		eloop_register_timeout(GAS_QUERY_TIMEOUT_PERIOD, 0,
246				       gas_query_timeout, gas, query);
247		if (query->wait_comeback && !query->retry) {
248			eloop_cancel_timeout(gas_query_rx_comeback_timeout,
249					     gas, query);
250			eloop_register_timeout(
251				0, (GAS_QUERY_WAIT_TIME_COMEBACK + 10) * 1000,
252				gas_query_rx_comeback_timeout, gas, query);
253		}
254	}
255	if (result == OFFCHANNEL_SEND_ACTION_FAILED) {
256		eloop_cancel_timeout(gas_query_timeout, gas, query);
257		eloop_register_timeout(0, 0, gas_query_timeout, gas, query);
258	}
259}
260
261
262static int pmf_in_use(struct wpa_supplicant *wpa_s, const u8 *addr)
263{
264	if (wpa_s->current_ssid == NULL ||
265	    wpa_s->wpa_state < WPA_4WAY_HANDSHAKE ||
266	    os_memcmp(addr, wpa_s->bssid, ETH_ALEN) != 0)
267		return 0;
268	return wpa_sm_pmf_enabled(wpa_s->wpa);
269}
270
271
272static int gas_query_tx(struct gas_query *gas, struct gas_query_pending *query,
273			struct wpabuf *req, unsigned int wait_time)
274{
275	int res, prot = pmf_in_use(gas->wpa_s, query->addr);
276
277	wpa_printf(MSG_DEBUG, "GAS: Send action frame to " MACSTR " len=%u "
278		   "freq=%d prot=%d", MAC2STR(query->addr),
279		   (unsigned int) wpabuf_len(req), query->freq, prot);
280	if (prot) {
281		u8 *categ = wpabuf_mhead_u8(req);
282		*categ = WLAN_ACTION_PROTECTED_DUAL;
283	}
284	os_get_reltime(&query->last_oper);
285	if (gas->wpa_s->max_remain_on_chan &&
286	    wait_time > gas->wpa_s->max_remain_on_chan)
287		wait_time = gas->wpa_s->max_remain_on_chan;
288	res = offchannel_send_action(gas->wpa_s, query->freq, query->addr,
289				     gas->wpa_s->own_addr, query->addr,
290				     wpabuf_head(req), wpabuf_len(req),
291				     wait_time, gas_query_tx_status, 0);
292	if (res == 0)
293		query->offchannel_tx_started = 1;
294	return res;
295}
296
297
298static void gas_query_tx_comeback_req(struct gas_query *gas,
299				      struct gas_query_pending *query)
300{
301	struct wpabuf *req;
302	unsigned int wait_time;
303
304	req = gas_build_comeback_req(query->dialog_token);
305	if (req == NULL) {
306		gas_query_done(gas, query, GAS_QUERY_INTERNAL_ERROR);
307		return;
308	}
309
310	wait_time = (query->retry || !query->offchannel_tx_started) ?
311		GAS_QUERY_WAIT_TIME_INITIAL : GAS_QUERY_WAIT_TIME_COMEBACK;
312
313	if (gas_query_tx(gas, query, req, wait_time) < 0) {
314		wpa_printf(MSG_DEBUG, "GAS: Failed to send Action frame to "
315			   MACSTR, MAC2STR(query->addr));
316		gas_query_done(gas, query, GAS_QUERY_INTERNAL_ERROR);
317	}
318
319	wpabuf_free(req);
320}
321
322
323static void gas_query_rx_comeback_timeout(void *eloop_data, void *user_ctx)
324{
325	struct gas_query *gas = eloop_data;
326	struct gas_query_pending *query = user_ctx;
327	int dialog_token;
328
329	wpa_printf(MSG_DEBUG,
330		   "GAS: No response to comeback request received (retry=%u)",
331		   query->retry);
332	if (gas->current != query || query->retry)
333		return;
334	dialog_token = gas_query_new_dialog_token(gas, query->addr);
335	if (dialog_token < 0)
336		return;
337	wpa_printf(MSG_DEBUG,
338		   "GAS: Retry GAS query due to comeback response timeout");
339	query->retry = 1;
340	query->dialog_token = dialog_token;
341	*(wpabuf_mhead_u8(query->req) + 2) = dialog_token;
342	query->wait_comeback = 0;
343	query->next_frag_id = 0;
344	wpabuf_free(query->adv_proto);
345	query->adv_proto = NULL;
346	eloop_cancel_timeout(gas_query_tx_comeback_timeout, gas, query);
347	eloop_cancel_timeout(gas_query_timeout, gas, query);
348	gas_query_tx_initial_req(gas, query);
349}
350
351
352static void gas_query_tx_comeback_timeout(void *eloop_data, void *user_ctx)
353{
354	struct gas_query *gas = eloop_data;
355	struct gas_query_pending *query = user_ctx;
356
357	wpa_printf(MSG_DEBUG, "GAS: Comeback timeout for request to " MACSTR,
358		   MAC2STR(query->addr));
359	gas_query_tx_comeback_req(gas, query);
360}
361
362
363static void gas_query_tx_comeback_req_delay(struct gas_query *gas,
364					    struct gas_query_pending *query,
365					    u16 comeback_delay)
366{
367	unsigned int secs, usecs;
368
369	if (comeback_delay > 1 && query->offchannel_tx_started) {
370		offchannel_send_action_done(gas->wpa_s);
371		query->offchannel_tx_started = 0;
372	}
373
374	secs = (comeback_delay * 1024) / 1000000;
375	usecs = comeback_delay * 1024 - secs * 1000000;
376	wpa_printf(MSG_DEBUG, "GAS: Send comeback request to " MACSTR
377		   " in %u secs %u usecs", MAC2STR(query->addr), secs, usecs);
378	eloop_cancel_timeout(gas_query_tx_comeback_timeout, gas, query);
379	eloop_register_timeout(secs, usecs, gas_query_tx_comeback_timeout,
380			       gas, query);
381}
382
383
384static void gas_query_rx_initial(struct gas_query *gas,
385				 struct gas_query_pending *query,
386				 const u8 *adv_proto, const u8 *resp,
387				 size_t len, u16 comeback_delay)
388{
389	wpa_printf(MSG_DEBUG, "GAS: Received initial response from "
390		   MACSTR " (dialog_token=%u comeback_delay=%u)",
391		   MAC2STR(query->addr), query->dialog_token, comeback_delay);
392
393	query->adv_proto = wpabuf_alloc_copy(adv_proto, 2 + adv_proto[1]);
394	if (query->adv_proto == NULL) {
395		gas_query_done(gas, query, GAS_QUERY_INTERNAL_ERROR);
396		return;
397	}
398
399	if (comeback_delay) {
400		query->wait_comeback = 1;
401		gas_query_tx_comeback_req_delay(gas, query, comeback_delay);
402		return;
403	}
404
405	/* Query was completed without comeback mechanism */
406	if (gas_query_append(query, resp, len) < 0) {
407		gas_query_done(gas, query, GAS_QUERY_INTERNAL_ERROR);
408		return;
409	}
410
411	gas_query_done(gas, query, GAS_QUERY_SUCCESS);
412}
413
414
415static void gas_query_rx_comeback(struct gas_query *gas,
416				  struct gas_query_pending *query,
417				  const u8 *adv_proto, const u8 *resp,
418				  size_t len, u8 frag_id, u8 more_frags,
419				  u16 comeback_delay)
420{
421	wpa_printf(MSG_DEBUG, "GAS: Received comeback response from "
422		   MACSTR " (dialog_token=%u frag_id=%u more_frags=%u "
423		   "comeback_delay=%u)",
424		   MAC2STR(query->addr), query->dialog_token, frag_id,
425		   more_frags, comeback_delay);
426	eloop_cancel_timeout(gas_query_rx_comeback_timeout, gas, query);
427
428	if ((size_t) 2 + adv_proto[1] != wpabuf_len(query->adv_proto) ||
429	    os_memcmp(adv_proto, wpabuf_head(query->adv_proto),
430		      wpabuf_len(query->adv_proto)) != 0) {
431		wpa_printf(MSG_DEBUG, "GAS: Advertisement Protocol changed "
432			   "between initial and comeback response from "
433			   MACSTR, MAC2STR(query->addr));
434		gas_query_done(gas, query, GAS_QUERY_PEER_ERROR);
435		return;
436	}
437
438	if (comeback_delay) {
439		if (frag_id) {
440			wpa_printf(MSG_DEBUG, "GAS: Invalid comeback response "
441				   "with non-zero frag_id and comeback_delay "
442				   "from " MACSTR, MAC2STR(query->addr));
443			gas_query_done(gas, query, GAS_QUERY_PEER_ERROR);
444			return;
445		}
446		gas_query_tx_comeback_req_delay(gas, query, comeback_delay);
447		return;
448	}
449
450	if (frag_id != query->next_frag_id) {
451		wpa_printf(MSG_DEBUG, "GAS: Unexpected frag_id in response "
452			   "from " MACSTR, MAC2STR(query->addr));
453		if (frag_id + 1 == query->next_frag_id) {
454			wpa_printf(MSG_DEBUG, "GAS: Drop frame as possible "
455				   "retry of previous fragment");
456			return;
457		}
458		gas_query_done(gas, query, GAS_QUERY_PEER_ERROR);
459		return;
460	}
461	query->next_frag_id++;
462
463	if (gas_query_append(query, resp, len) < 0) {
464		gas_query_done(gas, query, GAS_QUERY_INTERNAL_ERROR);
465		return;
466	}
467
468	if (more_frags) {
469		gas_query_tx_comeback_req(gas, query);
470		return;
471	}
472
473	gas_query_done(gas, query, GAS_QUERY_SUCCESS);
474}
475
476
477/**
478 * gas_query_rx - Indicate reception of a Public Action or Protected Dual frame
479 * @gas: GAS query data from gas_query_init()
480 * @da: Destination MAC address of the Action frame
481 * @sa: Source MAC address of the Action frame
482 * @bssid: BSSID of the Action frame
483 * @categ: Category of the Action frame
484 * @data: Payload of the Action frame
485 * @len: Length of @data
486 * @freq: Frequency (in MHz) on which the frame was received
487 * Returns: 0 if the Public Action frame was a GAS frame or -1 if not
488 */
489int gas_query_rx(struct gas_query *gas, const u8 *da, const u8 *sa,
490		 const u8 *bssid, u8 categ, const u8 *data, size_t len,
491		 int freq)
492{
493	struct gas_query_pending *query;
494	u8 action, dialog_token, frag_id = 0, more_frags = 0;
495	u16 comeback_delay, resp_len;
496	const u8 *pos, *adv_proto;
497	int prot, pmf;
498	unsigned int left;
499
500	if (gas == NULL || len < 4)
501		return -1;
502
503	prot = categ == WLAN_ACTION_PROTECTED_DUAL;
504	pmf = pmf_in_use(gas->wpa_s, sa);
505	if (prot && !pmf) {
506		wpa_printf(MSG_DEBUG, "GAS: Drop unexpected protected GAS frame when PMF is disabled");
507		return 0;
508	}
509	if (!prot && pmf) {
510		wpa_printf(MSG_DEBUG, "GAS: Drop unexpected unprotected GAS frame when PMF is enabled");
511		return 0;
512	}
513
514	pos = data;
515	action = *pos++;
516	dialog_token = *pos++;
517
518	if (action != WLAN_PA_GAS_INITIAL_RESP &&
519	    action != WLAN_PA_GAS_COMEBACK_RESP)
520		return -1; /* Not a GAS response */
521
522	query = gas_query_get_pending(gas, sa, dialog_token);
523	if (query == NULL) {
524		wpa_printf(MSG_DEBUG, "GAS: No pending query found for " MACSTR
525			   " dialog token %u", MAC2STR(sa), dialog_token);
526		return -1;
527	}
528
529	wpa_printf(MSG_DEBUG, "GAS: Response in %d ms from " MACSTR,
530		   ms_from_time(&query->last_oper), MAC2STR(sa));
531
532	if (query->wait_comeback && action == WLAN_PA_GAS_INITIAL_RESP) {
533		wpa_printf(MSG_DEBUG, "GAS: Unexpected initial response from "
534			   MACSTR " dialog token %u when waiting for comeback "
535			   "response", MAC2STR(sa), dialog_token);
536		return 0;
537	}
538
539	if (!query->wait_comeback && action == WLAN_PA_GAS_COMEBACK_RESP) {
540		wpa_printf(MSG_DEBUG, "GAS: Unexpected comeback response from "
541			   MACSTR " dialog token %u when waiting for initial "
542			   "response", MAC2STR(sa), dialog_token);
543		return 0;
544	}
545
546	query->status_code = WPA_GET_LE16(pos);
547	pos += 2;
548
549	if (query->status_code == WLAN_STATUS_QUERY_RESP_OUTSTANDING &&
550	    action == WLAN_PA_GAS_COMEBACK_RESP) {
551		wpa_printf(MSG_DEBUG, "GAS: Allow non-zero status for outstanding comeback response");
552	} else if (query->status_code != WLAN_STATUS_SUCCESS) {
553		wpa_printf(MSG_DEBUG, "GAS: Query to " MACSTR " dialog token "
554			   "%u failed - status code %u",
555			   MAC2STR(sa), dialog_token, query->status_code);
556		gas_query_done(gas, query, GAS_QUERY_FAILURE);
557		return 0;
558	}
559
560	if (action == WLAN_PA_GAS_COMEBACK_RESP) {
561		if (pos + 1 > data + len)
562			return 0;
563		frag_id = *pos & 0x7f;
564		more_frags = (*pos & 0x80) >> 7;
565		pos++;
566	}
567
568	/* Comeback Delay */
569	if (pos + 2 > data + len)
570		return 0;
571	comeback_delay = WPA_GET_LE16(pos);
572	pos += 2;
573
574	/* Advertisement Protocol element */
575	if (pos + 2 > data + len || pos + 2 + pos[1] > data + len) {
576		wpa_printf(MSG_DEBUG, "GAS: No room for Advertisement "
577			   "Protocol element in the response from " MACSTR,
578			   MAC2STR(sa));
579		return 0;
580	}
581
582	if (*pos != WLAN_EID_ADV_PROTO) {
583		wpa_printf(MSG_DEBUG, "GAS: Unexpected Advertisement "
584			   "Protocol element ID %u in response from " MACSTR,
585			   *pos, MAC2STR(sa));
586		return 0;
587	}
588
589	adv_proto = pos;
590	pos += 2 + pos[1];
591
592	/* Query Response Length */
593	if (pos + 2 > data + len) {
594		wpa_printf(MSG_DEBUG, "GAS: No room for GAS Response Length");
595		return 0;
596	}
597	resp_len = WPA_GET_LE16(pos);
598	pos += 2;
599
600	left = data + len - pos;
601	if (resp_len > left) {
602		wpa_printf(MSG_DEBUG, "GAS: Truncated Query Response in "
603			   "response from " MACSTR, MAC2STR(sa));
604		return 0;
605	}
606
607	if (resp_len < left) {
608		wpa_printf(MSG_DEBUG, "GAS: Ignore %u octets of extra data "
609			   "after Query Response from " MACSTR,
610			   left - resp_len, MAC2STR(sa));
611	}
612
613	if (action == WLAN_PA_GAS_COMEBACK_RESP)
614		gas_query_rx_comeback(gas, query, adv_proto, pos, resp_len,
615				      frag_id, more_frags, comeback_delay);
616	else
617		gas_query_rx_initial(gas, query, adv_proto, pos, resp_len,
618				     comeback_delay);
619
620	return 0;
621}
622
623
624static void gas_query_timeout(void *eloop_data, void *user_ctx)
625{
626	struct gas_query *gas = eloop_data;
627	struct gas_query_pending *query = user_ctx;
628
629	wpa_printf(MSG_DEBUG, "GAS: No response received for query to " MACSTR
630		   " dialog token %u",
631		   MAC2STR(query->addr), query->dialog_token);
632	gas_query_done(gas, query, GAS_QUERY_TIMEOUT);
633}
634
635
636static int gas_query_dialog_token_available(struct gas_query *gas,
637					    const u8 *dst, u8 dialog_token)
638{
639	struct gas_query_pending *q;
640	dl_list_for_each(q, &gas->pending, struct gas_query_pending, list) {
641		if (os_memcmp(dst, q->addr, ETH_ALEN) == 0 &&
642		    dialog_token == q->dialog_token)
643			return 0;
644	}
645
646	return 1;
647}
648
649
650static void gas_query_start_cb(struct wpa_radio_work *work, int deinit)
651{
652	struct gas_query_pending *query = work->ctx;
653	struct gas_query *gas = query->gas;
654	struct wpa_supplicant *wpa_s = gas->wpa_s;
655
656	if (deinit) {
657		if (work->started) {
658			gas->work = NULL;
659			gas_query_done(gas, query, GAS_QUERY_DELETED_AT_DEINIT);
660			return;
661		}
662
663		gas_query_free(query, 1);
664		return;
665	}
666
667	if (wpas_update_random_addr_disassoc(wpa_s) < 0) {
668		wpa_msg(wpa_s, MSG_INFO,
669			"Failed to assign random MAC address for GAS");
670		gas_query_free(query, 1);
671		radio_work_done(work);
672		return;
673	}
674
675	gas->work = work;
676	gas_query_tx_initial_req(gas, query);
677}
678
679
680static void gas_query_tx_initial_req(struct gas_query *gas,
681				     struct gas_query_pending *query)
682{
683	if (gas_query_tx(gas, query, query->req,
684			 GAS_QUERY_WAIT_TIME_INITIAL) < 0) {
685		wpa_printf(MSG_DEBUG, "GAS: Failed to send Action frame to "
686			   MACSTR, MAC2STR(query->addr));
687		gas_query_free(query, 1);
688		return;
689	}
690	gas->current = query;
691
692	wpa_printf(MSG_DEBUG, "GAS: Starting query timeout for dialog token %u",
693		   query->dialog_token);
694	eloop_register_timeout(GAS_QUERY_TIMEOUT_PERIOD, 0,
695			       gas_query_timeout, gas, query);
696}
697
698
699static int gas_query_new_dialog_token(struct gas_query *gas, const u8 *dst)
700{
701	static int next_start = 0;
702	int dialog_token;
703
704	for (dialog_token = 0; dialog_token < 256; dialog_token++) {
705		if (gas_query_dialog_token_available(
706			    gas, dst, (next_start + dialog_token) % 256))
707			break;
708	}
709	if (dialog_token == 256)
710		return -1; /* Too many pending queries */
711	dialog_token = (next_start + dialog_token) % 256;
712	next_start = (dialog_token + 1) % 256;
713	return dialog_token;
714}
715
716
717/**
718 * gas_query_req - Request a GAS query
719 * @gas: GAS query data from gas_query_init()
720 * @dst: Destination MAC address for the query
721 * @freq: Frequency (in MHz) for the channel on which to send the query
722 * @req: GAS query payload (to be freed by gas_query module in case of success
723 *	return)
724 * @cb: Callback function for reporting GAS query result and response
725 * @ctx: Context pointer to use with the @cb call
726 * Returns: dialog token (>= 0) on success or -1 on failure
727 */
728int gas_query_req(struct gas_query *gas, const u8 *dst, int freq,
729		  struct wpabuf *req,
730		  void (*cb)(void *ctx, const u8 *dst, u8 dialog_token,
731			     enum gas_query_result result,
732			     const struct wpabuf *adv_proto,
733			     const struct wpabuf *resp, u16 status_code),
734		  void *ctx)
735{
736	struct gas_query_pending *query;
737	int dialog_token;
738
739	if (wpabuf_len(req) < 3)
740		return -1;
741
742	dialog_token = gas_query_new_dialog_token(gas, dst);
743	if (dialog_token < 0)
744		return -1;
745
746	query = os_zalloc(sizeof(*query));
747	if (query == NULL)
748		return -1;
749
750	query->gas = gas;
751	os_memcpy(query->addr, dst, ETH_ALEN);
752	query->dialog_token = dialog_token;
753	query->freq = freq;
754	query->cb = cb;
755	query->ctx = ctx;
756	query->req = req;
757	dl_list_add(&gas->pending, &query->list);
758
759	*(wpabuf_mhead_u8(req) + 2) = dialog_token;
760
761	wpa_msg(gas->wpa_s, MSG_INFO, GAS_QUERY_START "addr=" MACSTR
762		" dialog_token=%u freq=%d",
763		MAC2STR(query->addr), query->dialog_token, query->freq);
764
765	if (radio_add_work(gas->wpa_s, freq, "gas-query", 0, gas_query_start_cb,
766			   query) < 0) {
767		gas_query_free(query, 1);
768		return -1;
769	}
770
771	return dialog_token;
772}
773
774
775/**
776 * gas_query_cancel - Cancel a pending GAS query
777 * @gas: GAS query data from gas_query_init()
778 * @dst: Destination MAC address for the query
779 * @dialog_token: Dialog token from gas_query_req()
780 */
781void gas_query_cancel(struct gas_query *gas, const u8 *dst, u8 dialog_token)
782{
783	struct gas_query_pending *query;
784
785	query = gas_query_get_pending(gas, dst, dialog_token);
786	if (query)
787		gas_query_done(gas, query, GAS_QUERY_CANCELLED);
788
789}
790