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>
7 * This software may be distributed under the terms of the BSD license.
8 * See README for more details.
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"
21 #include "offchannel.h"
22 #include "gas_query.h"
25 /** GAS query timeout in seconds */
26 #define GAS_QUERY_TIMEOUT_PERIOD 2
30 * struct gas_query_pending - Pending GAS query
32 struct gas_query_pending {
34 struct gas_query *gas;
38 unsigned int wait_comeback:1;
39 unsigned int offchannel_tx_started:1;
43 struct wpabuf *adv_proto;
45 struct os_reltime last_oper;
46 void (*cb)(void *ctx, const u8 *dst, u8 dialog_token,
47 enum gas_query_result result,
48 const struct wpabuf *adv_proto,
49 const struct wpabuf *resp, u16 status_code);
54 * struct gas_query - Internal GAS query data
57 struct wpa_supplicant *wpa_s;
58 struct dl_list pending; /* struct gas_query_pending */
59 struct gas_query_pending *current;
60 struct wpa_radio_work *work;
64 static void gas_query_tx_comeback_timeout(void *eloop_data, void *user_ctx);
65 static void gas_query_timeout(void *eloop_data, void *user_ctx);
68 static int ms_from_time(struct os_reltime *last)
70 struct os_reltime now, res;
73 os_reltime_sub(&now, last, &res);
74 return res.sec * 1000 + res.usec / 1000;
79 * gas_query_init - Initialize GAS query component
80 * @wpa_s: Pointer to wpa_supplicant data
81 * Returns: Pointer to GAS query data or %NULL on failure
83 struct gas_query * gas_query_init(struct wpa_supplicant *wpa_s)
85 struct gas_query *gas;
87 gas = os_zalloc(sizeof(*gas));
92 dl_list_init(&gas->pending);
98 static const char * gas_result_txt(enum gas_query_result result)
101 case GAS_QUERY_SUCCESS:
103 case GAS_QUERY_FAILURE:
105 case GAS_QUERY_TIMEOUT:
107 case GAS_QUERY_PEER_ERROR:
109 case GAS_QUERY_INTERNAL_ERROR:
110 return "INTERNAL_ERROR";
111 case GAS_QUERY_CANCELLED:
113 case GAS_QUERY_DELETED_AT_DEINIT:
114 return "DELETED_AT_DEINIT";
121 static void gas_query_free(struct gas_query_pending *query, int del_list)
123 struct gas_query *gas = query->gas;
126 dl_list_del(&query->list);
128 if (gas->work && gas->work->ctx == query) {
129 radio_work_done(gas->work);
133 wpabuf_free(query->req);
134 wpabuf_free(query->adv_proto);
135 wpabuf_free(query->resp);
140 static void gas_query_done(struct gas_query *gas,
141 struct gas_query_pending *query,
142 enum gas_query_result result)
144 wpa_msg(gas->wpa_s, MSG_INFO, GAS_QUERY_DONE "addr=" MACSTR
145 " dialog_token=%u freq=%d status_code=%u result=%s",
146 MAC2STR(query->addr), query->dialog_token, query->freq,
147 query->status_code, gas_result_txt(result));
148 if (gas->current == query)
150 if (query->offchannel_tx_started)
151 offchannel_send_action_done(gas->wpa_s);
152 eloop_cancel_timeout(gas_query_tx_comeback_timeout, gas, query);
153 eloop_cancel_timeout(gas_query_timeout, gas, query);
154 dl_list_del(&query->list);
155 query->cb(query->ctx, query->addr, query->dialog_token, result,
156 query->adv_proto, query->resp, query->status_code);
157 gas_query_free(query, 0);
162 * gas_query_deinit - Deinitialize GAS query component
163 * @gas: GAS query data from gas_query_init()
165 void gas_query_deinit(struct gas_query *gas)
167 struct gas_query_pending *query, *next;
172 dl_list_for_each_safe(query, next, &gas->pending,
173 struct gas_query_pending, list)
174 gas_query_done(gas, query, GAS_QUERY_DELETED_AT_DEINIT);
180 static struct gas_query_pending *
181 gas_query_get_pending(struct gas_query *gas, const u8 *addr, u8 dialog_token)
183 struct gas_query_pending *q;
184 dl_list_for_each(q, &gas->pending, struct gas_query_pending, list) {
185 if (os_memcmp(q->addr, addr, ETH_ALEN) == 0 &&
186 q->dialog_token == dialog_token)
193 static int gas_query_append(struct gas_query_pending *query, const u8 *data,
196 if (wpabuf_resize(&query->resp, len) < 0) {
197 wpa_printf(MSG_DEBUG, "GAS: No memory to store the response");
200 wpabuf_put_data(query->resp, data, len);
205 static void gas_query_tx_status(struct wpa_supplicant *wpa_s,
206 unsigned int freq, const u8 *dst,
207 const u8 *src, const u8 *bssid,
208 const u8 *data, size_t data_len,
209 enum offchannel_send_action_result result)
211 struct gas_query_pending *query;
212 struct gas_query *gas = wpa_s->gas;
215 if (gas->current == NULL) {
216 wpa_printf(MSG_DEBUG, "GAS: Unexpected TX status: freq=%u dst="
217 MACSTR " result=%d - no query in progress",
218 freq, MAC2STR(dst), result);
222 query = gas->current;
224 dur = ms_from_time(&query->last_oper);
225 wpa_printf(MSG_DEBUG, "GAS: TX status: freq=%u dst=" MACSTR
226 " result=%d query=%p dialog_token=%u dur=%d ms",
227 freq, MAC2STR(dst), result, query, query->dialog_token, dur);
228 if (os_memcmp(dst, query->addr, ETH_ALEN) != 0) {
229 wpa_printf(MSG_DEBUG, "GAS: TX status for unexpected destination");
232 os_get_reltime(&query->last_oper);
234 if (result == OFFCHANNEL_SEND_ACTION_SUCCESS) {
235 eloop_cancel_timeout(gas_query_timeout, gas, query);
236 eloop_register_timeout(GAS_QUERY_TIMEOUT_PERIOD, 0,
237 gas_query_timeout, gas, query);
239 if (result == OFFCHANNEL_SEND_ACTION_FAILED) {
240 eloop_cancel_timeout(gas_query_timeout, gas, query);
241 eloop_register_timeout(0, 0, gas_query_timeout, gas, query);
246 static int pmf_in_use(struct wpa_supplicant *wpa_s, const u8 *addr)
248 if (wpa_s->current_ssid == NULL ||
249 wpa_s->wpa_state < WPA_4WAY_HANDSHAKE ||
250 os_memcmp(addr, wpa_s->bssid, ETH_ALEN) != 0)
252 return wpa_sm_pmf_enabled(wpa_s->wpa);
256 static int gas_query_tx(struct gas_query *gas, struct gas_query_pending *query,
259 unsigned int wait_time;
260 int res, prot = pmf_in_use(gas->wpa_s, query->addr);
262 wpa_printf(MSG_DEBUG, "GAS: Send action frame to " MACSTR " len=%u "
263 "freq=%d prot=%d", MAC2STR(query->addr),
264 (unsigned int) wpabuf_len(req), query->freq, prot);
266 u8 *categ = wpabuf_mhead_u8(req);
267 *categ = WLAN_ACTION_PROTECTED_DUAL;
269 os_get_reltime(&query->last_oper);
271 if (gas->wpa_s->max_remain_on_chan &&
272 wait_time > gas->wpa_s->max_remain_on_chan)
273 wait_time = gas->wpa_s->max_remain_on_chan;
274 res = offchannel_send_action(gas->wpa_s, query->freq, query->addr,
275 gas->wpa_s->own_addr, query->addr,
276 wpabuf_head(req), wpabuf_len(req),
277 wait_time, gas_query_tx_status, 0);
279 query->offchannel_tx_started = 1;
284 static void gas_query_tx_comeback_req(struct gas_query *gas,
285 struct gas_query_pending *query)
289 req = gas_build_comeback_req(query->dialog_token);
291 gas_query_done(gas, query, GAS_QUERY_INTERNAL_ERROR);
295 if (gas_query_tx(gas, query, req) < 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_INTERNAL_ERROR);
305 static void gas_query_tx_comeback_timeout(void *eloop_data, void *user_ctx)
307 struct gas_query *gas = eloop_data;
308 struct gas_query_pending *query = user_ctx;
310 wpa_printf(MSG_DEBUG, "GAS: Comeback timeout for request to " MACSTR,
311 MAC2STR(query->addr));
312 gas_query_tx_comeback_req(gas, query);
316 static void gas_query_tx_comeback_req_delay(struct gas_query *gas,
317 struct gas_query_pending *query,
320 unsigned int secs, usecs;
322 secs = (comeback_delay * 1024) / 1000000;
323 usecs = comeback_delay * 1024 - secs * 1000000;
324 wpa_printf(MSG_DEBUG, "GAS: Send comeback request to " MACSTR
325 " in %u secs %u usecs", MAC2STR(query->addr), secs, usecs);
326 eloop_cancel_timeout(gas_query_tx_comeback_timeout, gas, query);
327 eloop_register_timeout(secs, usecs, gas_query_tx_comeback_timeout,
332 static void gas_query_rx_initial(struct gas_query *gas,
333 struct gas_query_pending *query,
334 const u8 *adv_proto, const u8 *resp,
335 size_t len, u16 comeback_delay)
337 wpa_printf(MSG_DEBUG, "GAS: Received initial response from "
338 MACSTR " (dialog_token=%u comeback_delay=%u)",
339 MAC2STR(query->addr), query->dialog_token, comeback_delay);
341 query->adv_proto = wpabuf_alloc_copy(adv_proto, 2 + adv_proto[1]);
342 if (query->adv_proto == NULL) {
343 gas_query_done(gas, query, GAS_QUERY_INTERNAL_ERROR);
347 if (comeback_delay) {
348 query->wait_comeback = 1;
349 gas_query_tx_comeback_req_delay(gas, query, comeback_delay);
353 /* Query was completed without comeback mechanism */
354 if (gas_query_append(query, resp, len) < 0) {
355 gas_query_done(gas, query, GAS_QUERY_INTERNAL_ERROR);
359 gas_query_done(gas, query, GAS_QUERY_SUCCESS);
363 static void gas_query_rx_comeback(struct gas_query *gas,
364 struct gas_query_pending *query,
365 const u8 *adv_proto, const u8 *resp,
366 size_t len, u8 frag_id, u8 more_frags,
369 wpa_printf(MSG_DEBUG, "GAS: Received comeback response from "
370 MACSTR " (dialog_token=%u frag_id=%u more_frags=%u "
371 "comeback_delay=%u)",
372 MAC2STR(query->addr), query->dialog_token, frag_id,
373 more_frags, comeback_delay);
375 if ((size_t) 2 + adv_proto[1] != wpabuf_len(query->adv_proto) ||
376 os_memcmp(adv_proto, wpabuf_head(query->adv_proto),
377 wpabuf_len(query->adv_proto)) != 0) {
378 wpa_printf(MSG_DEBUG, "GAS: Advertisement Protocol changed "
379 "between initial and comeback response from "
380 MACSTR, MAC2STR(query->addr));
381 gas_query_done(gas, query, GAS_QUERY_PEER_ERROR);
385 if (comeback_delay) {
387 wpa_printf(MSG_DEBUG, "GAS: Invalid comeback response "
388 "with non-zero frag_id and comeback_delay "
389 "from " MACSTR, MAC2STR(query->addr));
390 gas_query_done(gas, query, GAS_QUERY_PEER_ERROR);
393 gas_query_tx_comeback_req_delay(gas, query, comeback_delay);
397 if (frag_id != query->next_frag_id) {
398 wpa_printf(MSG_DEBUG, "GAS: Unexpected frag_id in response "
399 "from " MACSTR, MAC2STR(query->addr));
400 if (frag_id + 1 == query->next_frag_id) {
401 wpa_printf(MSG_DEBUG, "GAS: Drop frame as possible "
402 "retry of previous fragment");
405 gas_query_done(gas, query, GAS_QUERY_PEER_ERROR);
408 query->next_frag_id++;
410 if (gas_query_append(query, resp, len) < 0) {
411 gas_query_done(gas, query, GAS_QUERY_INTERNAL_ERROR);
416 gas_query_tx_comeback_req(gas, query);
420 gas_query_done(gas, query, GAS_QUERY_SUCCESS);
425 * gas_query_rx - Indicate reception of a Public Action or Protected Dual frame
426 * @gas: GAS query data from gas_query_init()
427 * @da: Destination MAC address of the Action frame
428 * @sa: Source MAC address of the Action frame
429 * @bssid: BSSID of the Action frame
430 * @categ: Category of the Action frame
431 * @data: Payload of the Action frame
432 * @len: Length of @data
433 * @freq: Frequency (in MHz) on which the frame was received
434 * Returns: 0 if the Public Action frame was a GAS frame or -1 if not
436 int gas_query_rx(struct gas_query *gas, const u8 *da, const u8 *sa,
437 const u8 *bssid, u8 categ, const u8 *data, size_t len,
440 struct gas_query_pending *query;
441 u8 action, dialog_token, frag_id = 0, more_frags = 0;
442 u16 comeback_delay, resp_len;
443 const u8 *pos, *adv_proto;
447 if (gas == NULL || len < 4)
450 prot = categ == WLAN_ACTION_PROTECTED_DUAL;
451 pmf = pmf_in_use(gas->wpa_s, bssid);
453 wpa_printf(MSG_DEBUG, "GAS: Drop unexpected protected GAS frame when PMF is disabled");
457 wpa_printf(MSG_DEBUG, "GAS: Drop unexpected unprotected GAS frame when PMF is enabled");
463 dialog_token = *pos++;
465 if (action != WLAN_PA_GAS_INITIAL_RESP &&
466 action != WLAN_PA_GAS_COMEBACK_RESP)
467 return -1; /* Not a GAS response */
469 query = gas_query_get_pending(gas, sa, dialog_token);
471 wpa_printf(MSG_DEBUG, "GAS: No pending query found for " MACSTR
472 " dialog token %u", MAC2STR(sa), dialog_token);
476 wpa_printf(MSG_DEBUG, "GAS: Response in %d ms from " MACSTR,
477 ms_from_time(&query->last_oper), MAC2STR(sa));
479 if (query->wait_comeback && action == WLAN_PA_GAS_INITIAL_RESP) {
480 wpa_printf(MSG_DEBUG, "GAS: Unexpected initial response from "
481 MACSTR " dialog token %u when waiting for comeback "
482 "response", MAC2STR(sa), dialog_token);
486 if (!query->wait_comeback && action == WLAN_PA_GAS_COMEBACK_RESP) {
487 wpa_printf(MSG_DEBUG, "GAS: Unexpected comeback response from "
488 MACSTR " dialog token %u when waiting for initial "
489 "response", MAC2STR(sa), dialog_token);
493 query->status_code = WPA_GET_LE16(pos);
496 if (query->status_code == WLAN_STATUS_QUERY_RESP_OUTSTANDING &&
497 action == WLAN_PA_GAS_COMEBACK_RESP) {
498 wpa_printf(MSG_DEBUG, "GAS: Allow non-zero status for outstanding comeback response");
499 } else if (query->status_code != WLAN_STATUS_SUCCESS) {
500 wpa_printf(MSG_DEBUG, "GAS: Query to " MACSTR " dialog token "
501 "%u failed - status code %u",
502 MAC2STR(sa), dialog_token, query->status_code);
503 gas_query_done(gas, query, GAS_QUERY_FAILURE);
507 if (action == WLAN_PA_GAS_COMEBACK_RESP) {
508 if (pos + 1 > data + len)
510 frag_id = *pos & 0x7f;
511 more_frags = (*pos & 0x80) >> 7;
516 if (pos + 2 > data + len)
518 comeback_delay = WPA_GET_LE16(pos);
521 /* Advertisement Protocol element */
522 if (pos + 2 > data + len || pos + 2 + pos[1] > data + len) {
523 wpa_printf(MSG_DEBUG, "GAS: No room for Advertisement "
524 "Protocol element in the response from " MACSTR,
529 if (*pos != WLAN_EID_ADV_PROTO) {
530 wpa_printf(MSG_DEBUG, "GAS: Unexpected Advertisement "
531 "Protocol element ID %u in response from " MACSTR,
539 /* Query Response Length */
540 if (pos + 2 > data + len) {
541 wpa_printf(MSG_DEBUG, "GAS: No room for GAS Response Length");
544 resp_len = WPA_GET_LE16(pos);
547 left = data + len - pos;
548 if (resp_len > left) {
549 wpa_printf(MSG_DEBUG, "GAS: Truncated Query Response in "
550 "response from " MACSTR, MAC2STR(sa));
554 if (resp_len < left) {
555 wpa_printf(MSG_DEBUG, "GAS: Ignore %u octets of extra data "
556 "after Query Response from " MACSTR,
557 left - resp_len, MAC2STR(sa));
560 if (action == WLAN_PA_GAS_COMEBACK_RESP)
561 gas_query_rx_comeback(gas, query, adv_proto, pos, resp_len,
562 frag_id, more_frags, comeback_delay);
564 gas_query_rx_initial(gas, query, adv_proto, pos, resp_len,
571 static void gas_query_timeout(void *eloop_data, void *user_ctx)
573 struct gas_query *gas = eloop_data;
574 struct gas_query_pending *query = user_ctx;
576 wpa_printf(MSG_DEBUG, "GAS: No response received for query to " MACSTR
578 MAC2STR(query->addr), query->dialog_token);
579 gas_query_done(gas, query, GAS_QUERY_TIMEOUT);
583 static int gas_query_dialog_token_available(struct gas_query *gas,
584 const u8 *dst, u8 dialog_token)
586 struct gas_query_pending *q;
587 dl_list_for_each(q, &gas->pending, struct gas_query_pending, list) {
588 if (os_memcmp(dst, q->addr, ETH_ALEN) == 0 &&
589 dialog_token == q->dialog_token)
597 static void gas_query_start_cb(struct wpa_radio_work *work, int deinit)
599 struct gas_query_pending *query = work->ctx;
600 struct gas_query *gas = query->gas;
601 struct wpa_supplicant *wpa_s = gas->wpa_s;
606 gas_query_done(gas, query, GAS_QUERY_DELETED_AT_DEINIT);
610 gas_query_free(query, 1);
614 if (wpas_update_random_addr_disassoc(wpa_s) < 0) {
615 wpa_msg(wpa_s, MSG_INFO,
616 "Failed to assign random MAC address for GAS");
617 gas_query_free(query, 1);
618 radio_work_done(work);
624 if (gas_query_tx(gas, query, query->req) < 0) {
625 wpa_printf(MSG_DEBUG, "GAS: Failed to send Action frame to "
626 MACSTR, MAC2STR(query->addr));
627 gas_query_free(query, 1);
630 gas->current = query;
632 wpa_printf(MSG_DEBUG, "GAS: Starting query timeout for dialog token %u",
633 query->dialog_token);
634 eloop_register_timeout(GAS_QUERY_TIMEOUT_PERIOD, 0,
635 gas_query_timeout, gas, query);
641 * gas_query_req - Request a GAS query
642 * @gas: GAS query data from gas_query_init()
643 * @dst: Destination MAC address for the query
644 * @freq: Frequency (in MHz) for the channel on which to send the query
645 * @req: GAS query payload (to be freed by gas_query module in case of success
647 * @cb: Callback function for reporting GAS query result and response
648 * @ctx: Context pointer to use with the @cb call
649 * Returns: dialog token (>= 0) on success or -1 on failure
651 int gas_query_req(struct gas_query *gas, const u8 *dst, int freq,
653 void (*cb)(void *ctx, const u8 *dst, u8 dialog_token,
654 enum gas_query_result result,
655 const struct wpabuf *adv_proto,
656 const struct wpabuf *resp, u16 status_code),
659 struct gas_query_pending *query;
661 static int next_start = 0;
663 if (wpabuf_len(req) < 3)
666 for (dialog_token = 0; dialog_token < 256; dialog_token++) {
667 if (gas_query_dialog_token_available(
668 gas, dst, (next_start + dialog_token) % 256))
671 if (dialog_token == 256)
672 return -1; /* Too many pending queries */
673 dialog_token = (next_start + dialog_token) % 256;
674 next_start = (dialog_token + 1) % 256;
676 query = os_zalloc(sizeof(*query));
681 os_memcpy(query->addr, dst, ETH_ALEN);
682 query->dialog_token = dialog_token;
687 dl_list_add(&gas->pending, &query->list);
689 *(wpabuf_mhead_u8(req) + 2) = dialog_token;
691 wpa_msg(gas->wpa_s, MSG_INFO, GAS_QUERY_START "addr=" MACSTR
692 " dialog_token=%u freq=%d",
693 MAC2STR(query->addr), query->dialog_token, query->freq);
695 if (radio_add_work(gas->wpa_s, freq, "gas-query", 0, gas_query_start_cb,
697 gas_query_free(query, 1);
706 * gas_query_cancel - Cancel a pending GAS query
707 * @gas: GAS query data from gas_query_init()
708 * @dst: Destination MAC address for the query
709 * @dialog_token: Dialog token from gas_query_req()
711 void gas_query_cancel(struct gas_query *gas, const u8 *dst, u8 dialog_token)
713 struct gas_query_pending *query;
715 query = gas_query_get_pending(gas, dst, dialog_token);
717 gas_query_done(gas, query, GAS_QUERY_CANCELLED);