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 "config.h"
21#include "driver_i.h"
22#include "offchannel.h"
23#include "gas_query.h"
24
25
26/** GAS query timeout in seconds */
27#define GAS_QUERY_TIMEOUT_PERIOD 2
28
29/* GAS query wait-time / duration in ms */
30#define GAS_QUERY_WAIT_TIME_INITIAL 1000
31#define GAS_QUERY_WAIT_TIME_COMEBACK 150
32
33/**
34 * struct gas_query_pending - Pending GAS query
35 */
36struct gas_query_pending {
37	struct dl_list list;
38	struct gas_query *gas;
39	u8 addr[ETH_ALEN];
40	u8 dialog_token;
41	u8 next_frag_id;
42	unsigned int wait_comeback:1;
43	unsigned int offchannel_tx_started:1;
44	unsigned int retry:1;
45	unsigned int wildcard_bssid:1;
46	int freq;
47	u16 status_code;
48	struct wpabuf *req;
49	struct wpabuf *adv_proto;
50	struct wpabuf *resp;
51	struct os_reltime last_oper;
52	void (*cb)(void *ctx, const u8 *dst, u8 dialog_token,
53		   enum gas_query_result result,
54		   const struct wpabuf *adv_proto,
55		   const struct wpabuf *resp, u16 status_code);
56	void *ctx;
57	u8 sa[ETH_ALEN];
58};
59
60/**
61 * struct gas_query - Internal GAS query data
62 */
63struct gas_query {
64	struct wpa_supplicant *wpa_s;
65	struct dl_list pending; /* struct gas_query_pending */
66	struct gas_query_pending *current;
67	struct wpa_radio_work *work;
68	struct os_reltime last_mac_addr_rand;
69	int last_rand_sa_type;
70	u8 rand_addr[ETH_ALEN];
71};
72
73
74static void gas_query_tx_comeback_timeout(void *eloop_data, void *user_ctx);
75static void gas_query_timeout(void *eloop_data, void *user_ctx);
76static void gas_query_rx_comeback_timeout(void *eloop_data, void *user_ctx);
77static void gas_query_tx_initial_req(struct gas_query *gas,
78				     struct gas_query_pending *query);
79static int gas_query_new_dialog_token(struct gas_query *gas, const u8 *dst);
80
81
82static int ms_from_time(struct os_reltime *last)
83{
84	struct os_reltime now, res;
85
86	os_get_reltime(&now);
87	os_reltime_sub(&now, last, &res);
88	return res.sec * 1000 + res.usec / 1000;
89}
90
91
92/**
93 * gas_query_init - Initialize GAS query component
94 * @wpa_s: Pointer to wpa_supplicant data
95 * Returns: Pointer to GAS query data or %NULL on failure
96 */
97struct gas_query * gas_query_init(struct wpa_supplicant *wpa_s)
98{
99	struct gas_query *gas;
100
101	gas = os_zalloc(sizeof(*gas));
102	if (gas == NULL)
103		return NULL;
104
105	gas->wpa_s = wpa_s;
106	dl_list_init(&gas->pending);
107
108	return gas;
109}
110
111
112static const char * gas_result_txt(enum gas_query_result result)
113{
114	switch (result) {
115	case GAS_QUERY_SUCCESS:
116		return "SUCCESS";
117	case GAS_QUERY_FAILURE:
118		return "FAILURE";
119	case GAS_QUERY_TIMEOUT:
120		return "TIMEOUT";
121	case GAS_QUERY_PEER_ERROR:
122		return "PEER_ERROR";
123	case GAS_QUERY_INTERNAL_ERROR:
124		return "INTERNAL_ERROR";
125	case GAS_QUERY_STOPPED:
126		return "STOPPED";
127	case GAS_QUERY_DELETED_AT_DEINIT:
128		return "DELETED_AT_DEINIT";
129	}
130
131	return "N/A";
132}
133
134
135static void gas_query_free(struct gas_query_pending *query, int del_list)
136{
137	struct gas_query *gas = query->gas;
138
139	if (del_list)
140		dl_list_del(&query->list);
141
142	if (gas->work && gas->work->ctx == query) {
143		radio_work_done(gas->work);
144		gas->work = NULL;
145	}
146
147	wpabuf_free(query->req);
148	wpabuf_free(query->adv_proto);
149	wpabuf_free(query->resp);
150	os_free(query);
151}
152
153
154static void gas_query_done(struct gas_query *gas,
155			   struct gas_query_pending *query,
156			   enum gas_query_result result)
157{
158	wpa_msg(gas->wpa_s, MSG_INFO, GAS_QUERY_DONE "addr=" MACSTR
159		" dialog_token=%u freq=%d status_code=%u result=%s",
160		MAC2STR(query->addr), query->dialog_token, query->freq,
161		query->status_code, gas_result_txt(result));
162	if (gas->current == query)
163		gas->current = NULL;
164	if (query->offchannel_tx_started)
165		offchannel_send_action_done(gas->wpa_s);
166	eloop_cancel_timeout(gas_query_tx_comeback_timeout, gas, query);
167	eloop_cancel_timeout(gas_query_timeout, gas, query);
168	eloop_cancel_timeout(gas_query_rx_comeback_timeout, gas, query);
169	dl_list_del(&query->list);
170	query->cb(query->ctx, query->addr, query->dialog_token, result,
171		  query->adv_proto, query->resp, query->status_code);
172	gas_query_free(query, 0);
173}
174
175
176/**
177 * gas_query_deinit - Deinitialize GAS query component
178 * @gas: GAS query data from gas_query_init()
179 */
180void gas_query_deinit(struct gas_query *gas)
181{
182	struct gas_query_pending *query, *next;
183
184	if (gas == NULL)
185		return;
186
187	dl_list_for_each_safe(query, next, &gas->pending,
188			      struct gas_query_pending, list)
189		gas_query_done(gas, query, GAS_QUERY_DELETED_AT_DEINIT);
190
191	os_free(gas);
192}
193
194
195static struct gas_query_pending *
196gas_query_get_pending(struct gas_query *gas, const u8 *addr, u8 dialog_token)
197{
198	struct gas_query_pending *q;
199	dl_list_for_each(q, &gas->pending, struct gas_query_pending, list) {
200		if (os_memcmp(q->addr, addr, ETH_ALEN) == 0 &&
201		    q->dialog_token == dialog_token)
202			return q;
203	}
204	return NULL;
205}
206
207
208static int gas_query_append(struct gas_query_pending *query, const u8 *data,
209			    size_t len)
210{
211	if (wpabuf_resize(&query->resp, len) < 0) {
212		wpa_printf(MSG_DEBUG, "GAS: No memory to store the response");
213		return -1;
214	}
215	wpabuf_put_data(query->resp, data, len);
216	return 0;
217}
218
219
220static void gas_query_tx_status(struct wpa_supplicant *wpa_s,
221				unsigned int freq, const u8 *dst,
222				const u8 *src, const u8 *bssid,
223				const u8 *data, size_t data_len,
224				enum offchannel_send_action_result result)
225{
226	struct gas_query_pending *query;
227	struct gas_query *gas = wpa_s->gas;
228	int dur;
229
230	if (gas->current == NULL) {
231		wpa_printf(MSG_DEBUG, "GAS: Unexpected TX status: freq=%u dst="
232			   MACSTR " result=%d - no query in progress",
233			   freq, MAC2STR(dst), result);
234		return;
235	}
236
237	query = gas->current;
238
239	dur = ms_from_time(&query->last_oper);
240	wpa_printf(MSG_DEBUG, "GAS: TX status: freq=%u dst=" MACSTR
241		   " result=%d query=%p dialog_token=%u dur=%d ms",
242		   freq, MAC2STR(dst), result, query, query->dialog_token, dur);
243	if (os_memcmp(dst, query->addr, ETH_ALEN) != 0) {
244		wpa_printf(MSG_DEBUG, "GAS: TX status for unexpected destination");
245		return;
246	}
247	os_get_reltime(&query->last_oper);
248
249	if (result == OFFCHANNEL_SEND_ACTION_SUCCESS ||
250	    result == OFFCHANNEL_SEND_ACTION_NO_ACK) {
251		eloop_cancel_timeout(gas_query_timeout, gas, query);
252		if (result == OFFCHANNEL_SEND_ACTION_NO_ACK) {
253			wpa_printf(MSG_DEBUG, "GAS: No ACK to GAS request");
254			eloop_register_timeout(0, 250000,
255					       gas_query_timeout, gas, query);
256		} else {
257			eloop_register_timeout(GAS_QUERY_TIMEOUT_PERIOD, 0,
258					       gas_query_timeout, gas, query);
259		}
260		if (query->wait_comeback && !query->retry) {
261			eloop_cancel_timeout(gas_query_rx_comeback_timeout,
262					     gas, query);
263			eloop_register_timeout(
264				0, (GAS_QUERY_WAIT_TIME_COMEBACK + 10) * 1000,
265				gas_query_rx_comeback_timeout, gas, query);
266		}
267	}
268	if (result == OFFCHANNEL_SEND_ACTION_FAILED) {
269		eloop_cancel_timeout(gas_query_timeout, gas, query);
270		eloop_register_timeout(0, 0, gas_query_timeout, gas, query);
271	}
272}
273
274
275int pmf_in_use(struct wpa_supplicant *wpa_s, const u8 *addr)
276{
277	if (wpa_s->current_ssid == NULL ||
278	    wpa_s->wpa_state < WPA_4WAY_HANDSHAKE ||
279	    os_memcmp(addr, wpa_s->bssid, ETH_ALEN) != 0)
280		return 0;
281	return wpa_sm_pmf_enabled(wpa_s->wpa);
282}
283
284
285static int gas_query_tx(struct gas_query *gas, struct gas_query_pending *query,
286			struct wpabuf *req, unsigned int wait_time)
287{
288	int res, prot = pmf_in_use(gas->wpa_s, query->addr);
289	const u8 *bssid;
290	const u8 wildcard_bssid[ETH_ALEN] = {
291		0xff, 0xff, 0xff, 0xff, 0xff, 0xff
292	};
293
294	wpa_printf(MSG_DEBUG, "GAS: Send action frame to " MACSTR " len=%u "
295		   "freq=%d prot=%d using src addr " MACSTR,
296		   MAC2STR(query->addr), (unsigned int) wpabuf_len(req),
297		   query->freq, prot, MAC2STR(query->sa));
298	if (prot) {
299		u8 *categ = wpabuf_mhead_u8(req);
300		*categ = WLAN_ACTION_PROTECTED_DUAL;
301	}
302	os_get_reltime(&query->last_oper);
303	if (gas->wpa_s->max_remain_on_chan &&
304	    wait_time > gas->wpa_s->max_remain_on_chan)
305		wait_time = gas->wpa_s->max_remain_on_chan;
306	if (!query->wildcard_bssid &&
307	    (!gas->wpa_s->conf->gas_address3 ||
308	     (gas->wpa_s->current_ssid &&
309	      gas->wpa_s->wpa_state >= WPA_ASSOCIATED &&
310	      os_memcmp(query->addr, gas->wpa_s->bssid, ETH_ALEN) == 0)))
311		bssid = query->addr;
312	else
313		bssid = wildcard_bssid;
314
315	res = offchannel_send_action(gas->wpa_s, query->freq, query->addr,
316				     query->sa, bssid, wpabuf_head(req),
317				     wpabuf_len(req), wait_time,
318				     gas_query_tx_status, 0);
319
320	if (res == 0)
321		query->offchannel_tx_started = 1;
322	return res;
323}
324
325
326static void gas_query_tx_comeback_req(struct gas_query *gas,
327				      struct gas_query_pending *query)
328{
329	struct wpabuf *req;
330	unsigned int wait_time;
331
332	req = gas_build_comeback_req(query->dialog_token);
333	if (req == NULL) {
334		gas_query_done(gas, query, GAS_QUERY_INTERNAL_ERROR);
335		return;
336	}
337
338	wait_time = (query->retry || !query->offchannel_tx_started) ?
339		GAS_QUERY_WAIT_TIME_INITIAL : GAS_QUERY_WAIT_TIME_COMEBACK;
340
341	if (gas_query_tx(gas, query, req, wait_time) < 0) {
342		wpa_printf(MSG_DEBUG, "GAS: Failed to send Action frame to "
343			   MACSTR, MAC2STR(query->addr));
344		gas_query_done(gas, query, GAS_QUERY_INTERNAL_ERROR);
345	}
346
347	wpabuf_free(req);
348}
349
350
351static void gas_query_rx_comeback_timeout(void *eloop_data, void *user_ctx)
352{
353	struct gas_query *gas = eloop_data;
354	struct gas_query_pending *query = user_ctx;
355	int dialog_token;
356
357	wpa_printf(MSG_DEBUG,
358		   "GAS: No response to comeback request received (retry=%u)",
359		   query->retry);
360	if (gas->current != query || query->retry)
361		return;
362	dialog_token = gas_query_new_dialog_token(gas, query->addr);
363	if (dialog_token < 0)
364		return;
365	wpa_printf(MSG_DEBUG,
366		   "GAS: Retry GAS query due to comeback response timeout");
367	query->retry = 1;
368	query->dialog_token = dialog_token;
369	*(wpabuf_mhead_u8(query->req) + 2) = dialog_token;
370	query->wait_comeback = 0;
371	query->next_frag_id = 0;
372	wpabuf_free(query->adv_proto);
373	query->adv_proto = NULL;
374	eloop_cancel_timeout(gas_query_tx_comeback_timeout, gas, query);
375	eloop_cancel_timeout(gas_query_timeout, gas, query);
376	gas_query_tx_initial_req(gas, query);
377}
378
379
380static void gas_query_tx_comeback_timeout(void *eloop_data, void *user_ctx)
381{
382	struct gas_query *gas = eloop_data;
383	struct gas_query_pending *query = user_ctx;
384
385	wpa_printf(MSG_DEBUG, "GAS: Comeback timeout for request to " MACSTR,
386		   MAC2STR(query->addr));
387	gas_query_tx_comeback_req(gas, query);
388}
389
390
391static void gas_query_tx_comeback_req_delay(struct gas_query *gas,
392					    struct gas_query_pending *query,
393					    u16 comeback_delay)
394{
395	unsigned int secs, usecs;
396
397	if (comeback_delay > 1 && query->offchannel_tx_started) {
398		offchannel_send_action_done(gas->wpa_s);
399		query->offchannel_tx_started = 0;
400	}
401
402	secs = (comeback_delay * 1024) / 1000000;
403	usecs = comeback_delay * 1024 - secs * 1000000;
404	wpa_printf(MSG_DEBUG, "GAS: Send comeback request to " MACSTR
405		   " in %u secs %u usecs", MAC2STR(query->addr), secs, usecs);
406	eloop_cancel_timeout(gas_query_tx_comeback_timeout, gas, query);
407	eloop_register_timeout(secs, usecs, gas_query_tx_comeback_timeout,
408			       gas, query);
409}
410
411
412static void gas_query_rx_initial(struct gas_query *gas,
413				 struct gas_query_pending *query,
414				 const u8 *adv_proto, const u8 *resp,
415				 size_t len, u16 comeback_delay)
416{
417	wpa_printf(MSG_DEBUG, "GAS: Received initial response from "
418		   MACSTR " (dialog_token=%u comeback_delay=%u)",
419		   MAC2STR(query->addr), query->dialog_token, comeback_delay);
420
421	query->adv_proto = wpabuf_alloc_copy(adv_proto, 2 + adv_proto[1]);
422	if (query->adv_proto == NULL) {
423		gas_query_done(gas, query, GAS_QUERY_INTERNAL_ERROR);
424		return;
425	}
426
427	if (comeback_delay) {
428		eloop_cancel_timeout(gas_query_timeout, gas, query);
429		query->wait_comeback = 1;
430		gas_query_tx_comeback_req_delay(gas, query, comeback_delay);
431		return;
432	}
433
434	/* Query was completed without comeback mechanism */
435	if (gas_query_append(query, resp, len) < 0) {
436		gas_query_done(gas, query, GAS_QUERY_INTERNAL_ERROR);
437		return;
438	}
439
440	gas_query_done(gas, query, GAS_QUERY_SUCCESS);
441}
442
443
444static void gas_query_rx_comeback(struct gas_query *gas,
445				  struct gas_query_pending *query,
446				  const u8 *adv_proto, const u8 *resp,
447				  size_t len, u8 frag_id, u8 more_frags,
448				  u16 comeback_delay)
449{
450	wpa_printf(MSG_DEBUG, "GAS: Received comeback response from "
451		   MACSTR " (dialog_token=%u frag_id=%u more_frags=%u "
452		   "comeback_delay=%u)",
453		   MAC2STR(query->addr), query->dialog_token, frag_id,
454		   more_frags, comeback_delay);
455	eloop_cancel_timeout(gas_query_rx_comeback_timeout, gas, query);
456
457	if ((size_t) 2 + adv_proto[1] != wpabuf_len(query->adv_proto) ||
458	    os_memcmp(adv_proto, wpabuf_head(query->adv_proto),
459		      wpabuf_len(query->adv_proto)) != 0) {
460		wpa_printf(MSG_DEBUG, "GAS: Advertisement Protocol changed "
461			   "between initial and comeback response from "
462			   MACSTR, MAC2STR(query->addr));
463		gas_query_done(gas, query, GAS_QUERY_PEER_ERROR);
464		return;
465	}
466
467	if (comeback_delay) {
468		if (frag_id) {
469			wpa_printf(MSG_DEBUG, "GAS: Invalid comeback response "
470				   "with non-zero frag_id and comeback_delay "
471				   "from " MACSTR, MAC2STR(query->addr));
472			gas_query_done(gas, query, GAS_QUERY_PEER_ERROR);
473			return;
474		}
475		gas_query_tx_comeback_req_delay(gas, query, comeback_delay);
476		return;
477	}
478
479	if (frag_id != query->next_frag_id) {
480		wpa_printf(MSG_DEBUG, "GAS: Unexpected frag_id in response "
481			   "from " MACSTR, MAC2STR(query->addr));
482		if (frag_id + 1 == query->next_frag_id) {
483			wpa_printf(MSG_DEBUG, "GAS: Drop frame as possible "
484				   "retry of previous fragment");
485			return;
486		}
487		gas_query_done(gas, query, GAS_QUERY_PEER_ERROR);
488		return;
489	}
490	query->next_frag_id++;
491
492	if (gas_query_append(query, resp, len) < 0) {
493		gas_query_done(gas, query, GAS_QUERY_INTERNAL_ERROR);
494		return;
495	}
496
497	if (more_frags) {
498		gas_query_tx_comeback_req(gas, query);
499		return;
500	}
501
502	gas_query_done(gas, query, GAS_QUERY_SUCCESS);
503}
504
505
506/**
507 * gas_query_rx - Indicate reception of a Public Action or Protected Dual frame
508 * @gas: GAS query data from gas_query_init()
509 * @da: Destination MAC address of the Action frame
510 * @sa: Source MAC address of the Action frame
511 * @bssid: BSSID of the Action frame
512 * @categ: Category of the Action frame
513 * @data: Payload of the Action frame
514 * @len: Length of @data
515 * @freq: Frequency (in MHz) on which the frame was received
516 * Returns: 0 if the Public Action frame was a GAS frame or -1 if not
517 */
518int gas_query_rx(struct gas_query *gas, const u8 *da, const u8 *sa,
519		 const u8 *bssid, u8 categ, const u8 *data, size_t len,
520		 int freq)
521{
522	struct gas_query_pending *query;
523	u8 action, dialog_token, frag_id = 0, more_frags = 0;
524	u16 comeback_delay, resp_len;
525	const u8 *pos, *adv_proto;
526	int prot, pmf;
527	unsigned int left;
528
529	if (gas == NULL || len < 4)
530		return -1;
531
532	pos = data;
533	action = *pos++;
534	dialog_token = *pos++;
535
536	if (action != WLAN_PA_GAS_INITIAL_RESP &&
537	    action != WLAN_PA_GAS_COMEBACK_RESP)
538		return -1; /* Not a GAS response */
539
540	prot = categ == WLAN_ACTION_PROTECTED_DUAL;
541	pmf = pmf_in_use(gas->wpa_s, sa);
542	if (prot && !pmf) {
543		wpa_printf(MSG_DEBUG, "GAS: Drop unexpected protected GAS frame when PMF is disabled");
544		return 0;
545	}
546	if (!prot && pmf) {
547		wpa_printf(MSG_DEBUG, "GAS: Drop unexpected unprotected GAS frame when PMF is enabled");
548		return 0;
549	}
550
551	query = gas_query_get_pending(gas, sa, dialog_token);
552	if (query == NULL) {
553		wpa_printf(MSG_DEBUG, "GAS: No pending query found for " MACSTR
554			   " dialog token %u", MAC2STR(sa), dialog_token);
555		return -1;
556	}
557
558	wpa_printf(MSG_DEBUG, "GAS: Response in %d ms from " MACSTR,
559		   ms_from_time(&query->last_oper), MAC2STR(sa));
560
561	if (query->wait_comeback && action == WLAN_PA_GAS_INITIAL_RESP) {
562		wpa_printf(MSG_DEBUG, "GAS: Unexpected initial response from "
563			   MACSTR " dialog token %u when waiting for comeback "
564			   "response", MAC2STR(sa), dialog_token);
565		return 0;
566	}
567
568	if (!query->wait_comeback && action == WLAN_PA_GAS_COMEBACK_RESP) {
569		wpa_printf(MSG_DEBUG, "GAS: Unexpected comeback response from "
570			   MACSTR " dialog token %u when waiting for initial "
571			   "response", MAC2STR(sa), dialog_token);
572		return 0;
573	}
574
575	query->status_code = WPA_GET_LE16(pos);
576	pos += 2;
577
578	if (query->status_code == WLAN_STATUS_QUERY_RESP_OUTSTANDING &&
579	    action == WLAN_PA_GAS_COMEBACK_RESP) {
580		wpa_printf(MSG_DEBUG, "GAS: Allow non-zero status for outstanding comeback response");
581	} else if (query->status_code != WLAN_STATUS_SUCCESS) {
582		wpa_printf(MSG_DEBUG, "GAS: Query to " MACSTR " dialog token "
583			   "%u failed - status code %u",
584			   MAC2STR(sa), dialog_token, query->status_code);
585		gas_query_done(gas, query, GAS_QUERY_FAILURE);
586		return 0;
587	}
588
589	if (action == WLAN_PA_GAS_COMEBACK_RESP) {
590		if (pos + 1 > data + len)
591			return 0;
592		frag_id = *pos & 0x7f;
593		more_frags = (*pos & 0x80) >> 7;
594		pos++;
595	}
596
597	/* Comeback Delay */
598	if (pos + 2 > data + len)
599		return 0;
600	comeback_delay = WPA_GET_LE16(pos);
601	pos += 2;
602
603	/* Advertisement Protocol element */
604	if (pos + 2 > data + len || pos + 2 + pos[1] > data + len) {
605		wpa_printf(MSG_DEBUG, "GAS: No room for Advertisement "
606			   "Protocol element in the response from " MACSTR,
607			   MAC2STR(sa));
608		return 0;
609	}
610
611	if (*pos != WLAN_EID_ADV_PROTO) {
612		wpa_printf(MSG_DEBUG, "GAS: Unexpected Advertisement "
613			   "Protocol element ID %u in response from " MACSTR,
614			   *pos, MAC2STR(sa));
615		return 0;
616	}
617
618	adv_proto = pos;
619	pos += 2 + pos[1];
620
621	/* Query Response Length */
622	if (pos + 2 > data + len) {
623		wpa_printf(MSG_DEBUG, "GAS: No room for GAS Response Length");
624		return 0;
625	}
626	resp_len = WPA_GET_LE16(pos);
627	pos += 2;
628
629	left = data + len - pos;
630	if (resp_len > left) {
631		wpa_printf(MSG_DEBUG, "GAS: Truncated Query Response in "
632			   "response from " MACSTR, MAC2STR(sa));
633		return 0;
634	}
635
636	if (resp_len < left) {
637		wpa_printf(MSG_DEBUG, "GAS: Ignore %u octets of extra data "
638			   "after Query Response from " MACSTR,
639			   left - resp_len, MAC2STR(sa));
640	}
641
642	if (action == WLAN_PA_GAS_COMEBACK_RESP)
643		gas_query_rx_comeback(gas, query, adv_proto, pos, resp_len,
644				      frag_id, more_frags, comeback_delay);
645	else
646		gas_query_rx_initial(gas, query, adv_proto, pos, resp_len,
647				     comeback_delay);
648
649	return 0;
650}
651
652
653static void gas_query_timeout(void *eloop_data, void *user_ctx)
654{
655	struct gas_query *gas = eloop_data;
656	struct gas_query_pending *query = user_ctx;
657
658	wpa_printf(MSG_DEBUG, "GAS: No response received for query to " MACSTR
659		   " dialog token %u",
660		   MAC2STR(query->addr), query->dialog_token);
661	gas_query_done(gas, query, GAS_QUERY_TIMEOUT);
662}
663
664
665static int gas_query_dialog_token_available(struct gas_query *gas,
666					    const u8 *dst, u8 dialog_token)
667{
668	struct gas_query_pending *q;
669	dl_list_for_each(q, &gas->pending, struct gas_query_pending, list) {
670		if (os_memcmp(dst, q->addr, ETH_ALEN) == 0 &&
671		    dialog_token == q->dialog_token)
672			return 0;
673	}
674
675	return 1;
676}
677
678
679static void gas_query_start_cb(struct wpa_radio_work *work, int deinit)
680{
681	struct gas_query_pending *query = work->ctx;
682	struct gas_query *gas = query->gas;
683	struct wpa_supplicant *wpa_s = gas->wpa_s;
684
685	if (deinit) {
686		if (work->started) {
687			gas->work = NULL;
688			gas_query_done(gas, query, GAS_QUERY_DELETED_AT_DEINIT);
689			return;
690		}
691
692		gas_query_free(query, 1);
693		return;
694	}
695
696	if (wpas_update_random_addr_disassoc(wpa_s) < 0) {
697		wpa_msg(wpa_s, MSG_INFO,
698			"Failed to assign random MAC address for GAS");
699		gas_query_free(query, 1);
700		radio_work_done(work);
701		return;
702	}
703
704	gas->work = work;
705	gas_query_tx_initial_req(gas, query);
706}
707
708
709static void gas_query_tx_initial_req(struct gas_query *gas,
710				     struct gas_query_pending *query)
711{
712	if (gas_query_tx(gas, query, query->req,
713			 GAS_QUERY_WAIT_TIME_INITIAL) < 0) {
714		wpa_printf(MSG_DEBUG, "GAS: Failed to send Action frame to "
715			   MACSTR, MAC2STR(query->addr));
716		gas_query_done(gas, query, GAS_QUERY_INTERNAL_ERROR);
717		return;
718	}
719	gas->current = query;
720
721	wpa_printf(MSG_DEBUG, "GAS: Starting query timeout for dialog token %u",
722		   query->dialog_token);
723	eloop_register_timeout(GAS_QUERY_TIMEOUT_PERIOD, 0,
724			       gas_query_timeout, gas, query);
725}
726
727
728static int gas_query_new_dialog_token(struct gas_query *gas, const u8 *dst)
729{
730	static int next_start = 0;
731	int dialog_token;
732
733	for (dialog_token = 0; dialog_token < 256; dialog_token++) {
734		if (gas_query_dialog_token_available(
735			    gas, dst, (next_start + dialog_token) % 256))
736			break;
737	}
738	if (dialog_token == 256)
739		return -1; /* Too many pending queries */
740	dialog_token = (next_start + dialog_token) % 256;
741	next_start = (dialog_token + 1) % 256;
742	return dialog_token;
743}
744
745
746static int gas_query_set_sa(struct gas_query *gas,
747			    struct gas_query_pending *query)
748{
749	struct wpa_supplicant *wpa_s = gas->wpa_s;
750	struct os_reltime now;
751
752	if (!wpa_s->conf->gas_rand_mac_addr ||
753	    !(wpa_s->current_bss ?
754	      (wpa_s->drv_flags &
755	       WPA_DRIVER_FLAGS_MGMT_TX_RANDOM_TA_CONNECTED) :
756	      (wpa_s->drv_flags & WPA_DRIVER_FLAGS_MGMT_TX_RANDOM_TA))) {
757		/* Use own MAC address as the transmitter address */
758		os_memcpy(query->sa, wpa_s->own_addr, ETH_ALEN);
759		return 0;
760	}
761
762	os_get_reltime(&now);
763
764	if (wpa_s->conf->gas_rand_mac_addr == gas->last_rand_sa_type &&
765	    gas->last_mac_addr_rand.sec != 0 &&
766	    !os_reltime_expired(&now, &gas->last_mac_addr_rand,
767				wpa_s->conf->gas_rand_addr_lifetime)) {
768		wpa_printf(MSG_DEBUG,
769			   "GAS: Use the previously selected random transmitter address "
770			   MACSTR, MAC2STR(gas->rand_addr));
771		os_memcpy(query->sa, gas->rand_addr, ETH_ALEN);
772		return 0;
773	}
774
775	if (wpa_s->conf->gas_rand_mac_addr == 1 &&
776	    random_mac_addr(gas->rand_addr) < 0) {
777		wpa_printf(MSG_ERROR, "GAS: Failed to get random address");
778		return -1;
779	}
780
781	if (wpa_s->conf->gas_rand_mac_addr == 2 &&
782	    random_mac_addr_keep_oui(gas->rand_addr) < 0) {
783		wpa_printf(MSG_ERROR,
784			   "GAS: Failed to get random address with same OUI");
785		return -1;
786	}
787
788	wpa_printf(MSG_DEBUG, "GAS: Use a new random transmitter address "
789		   MACSTR, MAC2STR(gas->rand_addr));
790	os_memcpy(query->sa, gas->rand_addr, ETH_ALEN);
791	os_get_reltime(&gas->last_mac_addr_rand);
792	gas->last_rand_sa_type = wpa_s->conf->gas_rand_mac_addr;
793
794	return 0;
795}
796
797
798/**
799 * gas_query_req - Request a GAS query
800 * @gas: GAS query data from gas_query_init()
801 * @dst: Destination MAC address for the query
802 * @freq: Frequency (in MHz) for the channel on which to send the query
803 * @req: GAS query payload (to be freed by gas_query module in case of success
804 *	return)
805 * @cb: Callback function for reporting GAS query result and response
806 * @ctx: Context pointer to use with the @cb call
807 * Returns: dialog token (>= 0) on success or -1 on failure
808 */
809int gas_query_req(struct gas_query *gas, const u8 *dst, int freq,
810		  int wildcard_bssid, struct wpabuf *req,
811		  void (*cb)(void *ctx, const u8 *dst, u8 dialog_token,
812			     enum gas_query_result result,
813			     const struct wpabuf *adv_proto,
814			     const struct wpabuf *resp, u16 status_code),
815		  void *ctx)
816{
817	struct gas_query_pending *query;
818	int dialog_token;
819
820	if (wpabuf_len(req) < 3)
821		return -1;
822
823	dialog_token = gas_query_new_dialog_token(gas, dst);
824	if (dialog_token < 0)
825		return -1;
826
827	query = os_zalloc(sizeof(*query));
828	if (query == NULL)
829		return -1;
830
831	query->gas = gas;
832	if (gas_query_set_sa(gas, query)) {
833		os_free(query);
834		return -1;
835	}
836	os_memcpy(query->addr, dst, ETH_ALEN);
837	query->dialog_token = dialog_token;
838	query->wildcard_bssid = !!wildcard_bssid;
839	query->freq = freq;
840	query->cb = cb;
841	query->ctx = ctx;
842	query->req = req;
843	dl_list_add(&gas->pending, &query->list);
844
845	*(wpabuf_mhead_u8(req) + 2) = dialog_token;
846
847	wpa_msg(gas->wpa_s, MSG_INFO, GAS_QUERY_START "addr=" MACSTR
848		" dialog_token=%u freq=%d",
849		MAC2STR(query->addr), query->dialog_token, query->freq);
850
851	if (radio_add_work(gas->wpa_s, freq, "gas-query", 0, gas_query_start_cb,
852			   query) < 0) {
853		query->req = NULL; /* caller will free this in error case */
854		gas_query_free(query, 1);
855		return -1;
856	}
857
858	return dialog_token;
859}
860
861
862int gas_query_stop(struct gas_query *gas, u8 dialog_token)
863{
864	struct gas_query_pending *query;
865
866	dl_list_for_each(query, &gas->pending, struct gas_query_pending, list) {
867		if (query->dialog_token == dialog_token) {
868			if (!gas->work) {
869				/* The pending radio work has not yet been
870				 * started, but the pending entry has a
871				 * reference to the soon to be freed query.
872				 * Need to remove that radio work now to avoid
873				 * leaving behind a reference to freed memory.
874				 */
875				radio_remove_pending_work(gas->wpa_s, query);
876			}
877			gas_query_done(gas, query, GAS_QUERY_STOPPED);
878			return 0;
879		}
880	}
881
882	return -1;
883}
884