2 * Generic advertisement service (GAS) query
3 * Copyright (c) 2009, Atheros Communications
4 * Copyright (c) 2011, Qualcomm Atheros
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
10 * Alternatively, this software may be distributed under the terms of BSD
13 * See README and COPYING for more details.
19 #include "utils/eloop.h"
20 #include "common/ieee802_11_defs.h"
21 #include "common/gas.h"
22 #include "wpa_supplicant_i.h"
24 #include "gas_query.h"
27 #define GAS_QUERY_TIMEOUT 5
30 struct gas_query_pending {
38 struct wpabuf *adv_proto;
40 void (*cb)(void *ctx, const u8 *dst, u8 dialog_token,
41 enum gas_query_result result,
42 const struct wpabuf *adv_proto,
43 const struct wpabuf *resp, u16 status_code);
48 struct wpa_supplicant *wpa_s;
49 struct dl_list pending; /* struct gas_query_pending */
53 static void gas_query_tx_comeback_timeout(void *eloop_data, void *user_ctx);
54 static void gas_query_timeout(void *eloop_data, void *user_ctx);
57 struct gas_query * gas_query_init(struct wpa_supplicant *wpa_s)
59 struct gas_query *gas;
61 gas = os_zalloc(sizeof(*gas));
66 dl_list_init(&gas->pending);
72 static void gas_query_done(struct gas_query *gas,
73 struct gas_query_pending *query,
74 enum gas_query_result result)
76 eloop_cancel_timeout(gas_query_tx_comeback_timeout, gas, query);
77 eloop_cancel_timeout(gas_query_timeout, gas, query);
78 dl_list_del(&query->list);
79 query->cb(query->ctx, query->addr, query->dialog_token, result,
80 query->adv_proto, query->resp, query->status_code);
81 wpabuf_free(query->adv_proto);
82 wpabuf_free(query->resp);
87 void gas_query_deinit(struct gas_query *gas)
89 struct gas_query_pending *query, *next;
94 dl_list_for_each_safe(query, next, &gas->pending,
95 struct gas_query_pending, list)
96 gas_query_done(gas, query, GAS_QUERY_DELETED_AT_DEINIT);
102 static struct gas_query_pending *
103 gas_query_get_pending(struct gas_query *gas, const u8 *addr, u8 dialog_token)
105 struct gas_query_pending *q;
106 dl_list_for_each(q, &gas->pending, struct gas_query_pending, list) {
107 if (os_memcmp(q->addr, addr, ETH_ALEN) == 0 &&
108 q->dialog_token == dialog_token)
115 static int gas_query_append(struct gas_query_pending *query, const u8 *data,
118 if (wpabuf_resize(&query->resp, len) < 0) {
119 wpa_printf(MSG_DEBUG, "GAS: No memory to store the response");
122 wpabuf_put_data(query->resp, data, len);
127 static int gas_query_tx(struct gas_query *gas, struct gas_query_pending *query,
130 wpa_printf(MSG_DEBUG, "GAS: Send action frame to " MACSTR " len=%u "
131 "freq=%d", MAC2STR(query->addr),
132 (unsigned int) wpabuf_len(req), query->freq);
133 return wpa_drv_send_action(gas->wpa_s, query->freq, 0, query->addr,
134 gas->wpa_s->own_addr, query->addr,
135 wpabuf_head(req), wpabuf_len(req));
139 static void gas_query_tx_comeback_req(struct gas_query *gas,
140 struct gas_query_pending *query)
144 req = gas_build_comeback_req(query->dialog_token);
146 gas_query_done(gas, query, GAS_QUERY_INTERNAL_ERROR);
150 if (gas_query_tx(gas, query, req) < 0) {
151 wpa_printf(MSG_DEBUG, "GAS: Failed to send Action frame to "
152 MACSTR, MAC2STR(query->addr));
153 gas_query_done(gas, query, GAS_QUERY_INTERNAL_ERROR);
160 static void gas_query_tx_comeback_timeout(void *eloop_data, void *user_ctx)
162 struct gas_query *gas = eloop_data;
163 struct gas_query_pending *query = user_ctx;
165 wpa_printf(MSG_DEBUG, "GAS: Comeback timeout for request to " MACSTR,
166 MAC2STR(query->addr));
167 gas_query_tx_comeback_req(gas, query);
171 static void gas_query_tx_comeback_req_delay(struct gas_query *gas,
172 struct gas_query_pending *query,
175 unsigned int secs, usecs;
177 secs = (comeback_delay * 1024) / 1000000;
178 usecs = comeback_delay * 1024 - secs * 1000000;
179 wpa_printf(MSG_DEBUG, "GAS: Send comeback request to " MACSTR
180 " in %u secs %u usecs", MAC2STR(query->addr), secs, usecs);
181 eloop_cancel_timeout(gas_query_tx_comeback_timeout, gas, query);
182 eloop_register_timeout(secs, usecs, gas_query_tx_comeback_timeout,
187 static void gas_query_rx_initial(struct gas_query *gas,
188 struct gas_query_pending *query,
189 const u8 *adv_proto, const u8 *resp,
190 size_t len, u16 comeback_delay)
192 wpa_printf(MSG_DEBUG, "GAS: Received initial response from "
193 MACSTR " (dialog_token=%u comeback_delay=%u)",
194 MAC2STR(query->addr), query->dialog_token, comeback_delay);
196 query->adv_proto = wpabuf_alloc_copy(adv_proto, 2 + adv_proto[1]);
197 if (query->adv_proto == NULL) {
198 gas_query_done(gas, query, GAS_QUERY_INTERNAL_ERROR);
202 if (comeback_delay) {
203 query->wait_comeback = 1;
204 gas_query_tx_comeback_req_delay(gas, query, comeback_delay);
208 /* Query was completed without comeback mechanism */
209 if (gas_query_append(query, resp, len) < 0) {
210 gas_query_done(gas, query, GAS_QUERY_INTERNAL_ERROR);
214 gas_query_done(gas, query, GAS_QUERY_SUCCESS);
218 static void gas_query_rx_comeback(struct gas_query *gas,
219 struct gas_query_pending *query,
220 const u8 *adv_proto, const u8 *resp,
221 size_t len, u8 frag_id, u8 more_frags,
224 wpa_printf(MSG_DEBUG, "GAS: Received comeback response from "
225 MACSTR " (dialog_token=%u frag_id=%u more_frags=%u "
226 "comeback_delay=%u)",
227 MAC2STR(query->addr), query->dialog_token, frag_id,
228 more_frags, comeback_delay);
230 if ((size_t) 2 + adv_proto[1] != wpabuf_len(query->adv_proto) ||
231 os_memcmp(adv_proto, wpabuf_head(query->adv_proto),
232 wpabuf_len(query->adv_proto)) != 0) {
233 wpa_printf(MSG_DEBUG, "GAS: Advertisement Protocol changed "
234 "between initial and comeback response from "
235 MACSTR, MAC2STR(query->addr));
236 gas_query_done(gas, query, GAS_QUERY_PEER_ERROR);
240 if (comeback_delay) {
242 wpa_printf(MSG_DEBUG, "GAS: Invalid comeback response "
243 "with non-zero frag_id and comeback_delay "
244 "from " MACSTR, MAC2STR(query->addr));
245 gas_query_done(gas, query, GAS_QUERY_PEER_ERROR);
248 gas_query_tx_comeback_req_delay(gas, query, comeback_delay);
252 if (frag_id != query->next_frag_id) {
253 wpa_printf(MSG_DEBUG, "GAS: Unexpected frag_id in response "
254 "from " MACSTR, MAC2STR(query->addr));
255 gas_query_done(gas, query, GAS_QUERY_PEER_ERROR);
258 query->next_frag_id++;
260 if (gas_query_append(query, resp, len) < 0) {
261 gas_query_done(gas, query, GAS_QUERY_INTERNAL_ERROR);
266 gas_query_tx_comeback_req(gas, query);
270 gas_query_done(gas, query, GAS_QUERY_SUCCESS);
274 int gas_query_rx(struct gas_query *gas, const u8 *da, const u8 *sa,
275 const u8 *bssid, const u8 *data, size_t len, int freq)
277 struct gas_query_pending *query;
278 u8 action, dialog_token, frag_id = 0, more_frags = 0;
279 u16 comeback_delay, resp_len;
280 const u8 *pos, *adv_proto;
282 if (gas == NULL || len < 4)
287 dialog_token = *pos++;
289 if (action != WLAN_PA_GAS_INITIAL_RESP &&
290 action != WLAN_PA_GAS_COMEBACK_RESP)
291 return -1; /* Not a GAS response */
293 query = gas_query_get_pending(gas, sa, dialog_token);
295 wpa_printf(MSG_DEBUG, "GAS: No pending query found for " MACSTR
296 " dialog token %u", MAC2STR(sa), dialog_token);
300 if (query->wait_comeback && action == WLAN_PA_GAS_INITIAL_RESP) {
301 wpa_printf(MSG_DEBUG, "GAS: Unexpected initial response from "
302 MACSTR " dialog token %u when waiting for comeback "
303 "response", MAC2STR(sa), dialog_token);
307 if (!query->wait_comeback && action == WLAN_PA_GAS_COMEBACK_RESP) {
308 wpa_printf(MSG_DEBUG, "GAS: Unexpected comeback response from "
309 MACSTR " dialog token %u when waiting for initial "
310 "response", MAC2STR(sa), dialog_token);
314 query->status_code = WPA_GET_LE16(pos);
317 if (query->status_code != WLAN_STATUS_SUCCESS) {
318 wpa_printf(MSG_DEBUG, "GAS: Query to " MACSTR " dialog token "
319 "%u failed - status code %u",
320 MAC2STR(sa), dialog_token, query->status_code);
321 gas_query_done(gas, query, GAS_QUERY_FAILURE);
325 if (action == WLAN_PA_GAS_COMEBACK_RESP) {
326 if (pos + 1 > data + len)
328 frag_id = *pos & 0x7f;
329 more_frags = (*pos & 0x80) >> 7;
334 if (pos + 2 > data + len)
336 comeback_delay = WPA_GET_LE16(pos);
339 /* Advertisement Protocol element */
340 if (pos + 2 > data + len || pos + 2 + pos[1] > data + len) {
341 wpa_printf(MSG_DEBUG, "GAS: No room for Advertisement "
342 "Protocol element in the response from " MACSTR,
347 if (*pos != WLAN_EID_ADV_PROTO) {
348 wpa_printf(MSG_DEBUG, "GAS: Unexpected Advertisement "
349 "Protocol element ID %u in response from " MACSTR,
357 /* Query Response Length */
358 if (pos + 2 > data + len) {
359 wpa_printf(MSG_DEBUG, "GAS: No room for GAS Response Length");
362 resp_len = WPA_GET_LE16(pos);
365 if (pos + resp_len > data + len) {
366 wpa_printf(MSG_DEBUG, "GAS: Truncated Query Response in "
367 "response from " MACSTR, MAC2STR(sa));
371 if (pos + resp_len < data + len) {
372 wpa_printf(MSG_DEBUG, "GAS: Ignore %u octets of extra data "
373 "after Query Response from " MACSTR,
374 (unsigned int) (data + len - pos - resp_len),
378 if (action == WLAN_PA_GAS_COMEBACK_RESP)
379 gas_query_rx_comeback(gas, query, adv_proto, pos, resp_len,
380 frag_id, more_frags, comeback_delay);
382 gas_query_rx_initial(gas, query, adv_proto, pos, resp_len,
389 static void gas_query_timeout(void *eloop_data, void *user_ctx)
391 struct gas_query *gas = eloop_data;
392 struct gas_query_pending *query = user_ctx;
394 wpa_printf(MSG_DEBUG, "GAS: No response received for query to " MACSTR,
395 MAC2STR(query->addr));
396 gas_query_done(gas, query, GAS_QUERY_TIMEOUT);
400 static int gas_query_dialog_token_available(struct gas_query *gas,
401 const u8 *dst, u8 dialog_token)
403 struct gas_query_pending *q;
404 dl_list_for_each(q, &gas->pending, struct gas_query_pending, list) {
405 if (os_memcmp(dst, q->addr, ETH_ALEN) == 0 &&
406 dialog_token == q->dialog_token)
414 int gas_query_req(struct gas_query *gas, const u8 *dst, int freq,
416 void (*cb)(void *ctx, const u8 *dst, u8 dialog_token,
417 enum gas_query_result result,
418 const struct wpabuf *adv_proto,
419 const struct wpabuf *resp, u16 status_code),
422 struct gas_query_pending *query;
425 if (wpabuf_len(req) < 3)
428 for (dialog_token = 0; dialog_token < 256; dialog_token++) {
429 if (gas_query_dialog_token_available(gas, dst, dialog_token))
432 if (dialog_token == 256)
433 return -1; /* Too many pending queries */
435 query = os_zalloc(sizeof(*query));
439 os_memcpy(query->addr, dst, ETH_ALEN);
440 query->dialog_token = dialog_token;
444 dl_list_add(&gas->pending, &query->list);
446 *(wpabuf_mhead_u8(req) + 2) = dialog_token;
448 wpa_printf(MSG_DEBUG, "GAS: Starting request for " MACSTR
449 " dialog_token %u", MAC2STR(dst), dialog_token);
450 if (gas_query_tx(gas, query, req) < 0) {
451 wpa_printf(MSG_DEBUG, "GAS: Failed to send Action frame to "
452 MACSTR, MAC2STR(query->addr));
457 eloop_register_timeout(GAS_QUERY_TIMEOUT, 0, gas_query_timeout,
464 void gas_query_cancel(struct gas_query *gas, const u8 *dst, u8 dialog_token)
466 struct gas_query_pending *query;
468 query = gas_query_get_pending(gas, dst, dialog_token);
470 gas_query_done(gas, query, GAS_QUERY_CANCELLED);