wpa_supplicant/gas_query.c

   1 /*
   2  * Generic advertisement service (GAS) query
   3  * Copyright (c) 2009, Atheros Communications
   4  * Copyright (c) 2011-2013, Qualcomm Atheros, Inc.
   5  *
   6  * This software may be distributed under the terms of the BSD license.
   7  * See README for more details.
   8  */
   9
  10 #include "includes.h"
  11
  12 #include "common.h"
  13 #include "utils/eloop.h"
  14 #include "common/ieee802_11_defs.h"
  15 #include "common/gas.h"
  16 #include "common/wpa_ctrl.h"
  17 #include "wpa_supplicant_i.h"
  18 #include "driver_i.h"
  19 #include "offchannel.h"
  20 #include "gas_query.h"
  21
  22
  23 /** GAS query timeout in seconds */
  24 #define GAS_QUERY_TIMEOUT_PERIOD 2
  25 /** Retry period for GAS query requests in milliseconds */
  26 #define GAS_SERVICE_RETRY_PERIOD_MS 500
  27
  28
  29 /**
  30  * struct gas_query_pending - Pending GAS query
  31  */
  32 struct gas_query_pending {
  33         struct dl_list list;
  34         u8 addr[ETH_ALEN];
  35         u8 dialog_token;
  36         u8 next_frag_id;
  37         unsigned int wait_comeback:1;
  38         unsigned int offchannel_tx_started:1;
  39         int freq;
  40         u16 status_code;
  41         struct wpabuf *req;
  42         struct wpabuf *adv_proto;
  43         struct wpabuf *resp;
  44         void (*cb)(void *ctx, const u8 *dst, u8 dialog_token,
  45                    enum gas_query_result result,
  46                    const struct wpabuf *adv_proto,
  47                    const struct wpabuf *resp, u16 status_code);
  48         void *ctx;
  49 };
  50
  51 /**
  52  * struct gas_query - Internal GAS query data
  53  */
  54 struct gas_query {
  55         struct wpa_supplicant *wpa_s;
  56         struct dl_list pending; /* struct gas_query_pending */
  57         struct gas_query_pending *current;
  58 };
  59
  60
  61 static void gas_query_tx_comeback_timeout(void *eloop_data, void *user_ctx);
  62 static void gas_query_timeout(void *eloop_data, void *user_ctx);
  63 static void gas_service_timeout(void *eloop_data, void *user_ctx);
  64
  65
  66 /**
  67  * gas_query_init - Initialize GAS query component
  68  * @wpa_s: Pointer to wpa_supplicant data
  69  * Returns: Pointer to GAS query data or %NULL on failure
  70  */
  71 struct gas_query * gas_query_init(struct wpa_supplicant *wpa_s)
  72 {
  73         struct gas_query *gas;
  74
  75         gas = os_zalloc(sizeof(*gas));
  76         if (gas == NULL)
  77                 return NULL;
  78
  79         gas->wpa_s = wpa_s;
  80         dl_list_init(&gas->pending);
  81
  82         return gas;
  83 }
  84
  85
  86 static const char * gas_result_txt(enum gas_query_result result)
  87 {
  88         switch (result) {
  89         case GAS_QUERY_SUCCESS:
  90                 return "SUCCESS";
  91         case GAS_QUERY_FAILURE:
  92                 return "FAILURE";
  93         case GAS_QUERY_TIMEOUT:
  94                 return "TIMEOUT";
  95         case GAS_QUERY_PEER_ERROR:
  96                 return "PEER_ERROR";
  97         case GAS_QUERY_INTERNAL_ERROR:
  98                 return "INTERNAL_ERROR";
  99         case GAS_QUERY_CANCELLED:
 100                 return "CANCELLED";
 101         case GAS_QUERY_DELETED_AT_DEINIT:
 102                 return "DELETED_AT_DEINIT";
 103         }
 104
 105         return "N/A";
 106 }
 107
 108
 109 static void gas_query_done(struct gas_query *gas,
 110                            struct gas_query_pending *query,
 111                            enum gas_query_result result)
 112 {
 113         wpa_msg(gas->wpa_s, MSG_INFO, GAS_QUERY_DONE "addr=" MACSTR
 114                 " dialog_token=%u freq=%d status_code=%u result=%s",
 115                 MAC2STR(query->addr), query->dialog_token, query->freq,
 116                 query->status_code, gas_result_txt(result));
 117         if (gas->current == query)
 118                 gas->current = NULL;
 119         if (query->offchannel_tx_started)
 120                 offchannel_send_action_done(gas->wpa_s);
 121         eloop_cancel_timeout(gas_query_tx_comeback_timeout, gas, query);
 122         eloop_cancel_timeout(gas_query_timeout, gas, query);
 123         eloop_cancel_timeout(gas_service_timeout, gas, query);
 124         dl_list_del(&query->list);
 125         query->cb(query->ctx, query->addr, query->dialog_token, result,
 126                   query->adv_proto, query->resp, query->status_code);
 127         wpabuf_free(query->req);
 128         wpabuf_free(query->adv_proto);
 129         wpabuf_free(query->resp);
 130         os_free(query);
 131 }
 132
 133
 134 /**
 135  * gas_query_deinit - Deinitialize GAS query component
 136  * @gas: GAS query data from gas_query_init()
 137  */
 138 void gas_query_deinit(struct gas_query *gas)
 139 {
 140         struct gas_query_pending *query, *next;
 141
 142         if (gas == NULL)
 143                 return;
 144
 145         dl_list_for_each_safe(query, next, &gas->pending,
 146                               struct gas_query_pending, list)
 147                 gas_query_done(gas, query, GAS_QUERY_DELETED_AT_DEINIT);
 148
 149         os_free(gas);
 150 }
 151
 152
 153 static struct gas_query_pending *
 154 gas_query_get_pending(struct gas_query *gas, const u8 *addr, u8 dialog_token)
 155 {
 156         struct gas_query_pending *q;
 157         dl_list_for_each(q, &gas->pending, struct gas_query_pending, list) {
 158                 if (os_memcmp(q->addr, addr, ETH_ALEN) == 0 &&
 159                     q->dialog_token == dialog_token)
 160                         return q;
 161         }
 162         return NULL;
 163 }
 164
 165
 166 static int gas_query_append(struct gas_query_pending *query, const u8 *data,
 167                             size_t len)
 168 {
 169         if (wpabuf_resize(&query->resp, len) < 0) {
 170                 wpa_printf(MSG_DEBUG, "GAS: No memory to store the response");
 171                 return -1;
 172         }
 173         wpabuf_put_data(query->resp, data, len);
 174         return 0;
 175 }
 176
 177
 178 static void gas_query_tx_status(struct wpa_supplicant *wpa_s,
 179                                 unsigned int freq, const u8 *dst,
 180                                 const u8 *src, const u8 *bssid,
 181                                 const u8 *data, size_t data_len,
 182                                 enum offchannel_send_action_result result)
 183 {
 184         struct gas_query_pending *query;
 185         struct gas_query *gas = wpa_s->gas;
 186
 187         if (gas->current == NULL) {
 188                 wpa_printf(MSG_DEBUG, "GAS: Unexpected TX status: freq=%u dst="
 189                            MACSTR " result=%d - no query in progress",
 190                            freq, MAC2STR(dst), result);
 191                 return;
 192         }
 193
 194         query = gas->current;
 195
 196         wpa_printf(MSG_DEBUG, "GAS: TX status: freq=%u dst=" MACSTR
 197                    " result=%d query=%p dialog_token=%u",
 198                    freq, MAC2STR(dst), result, query, query->dialog_token);
 199         if (os_memcmp(dst, query->addr, ETH_ALEN) != 0) {
 200                 wpa_printf(MSG_DEBUG, "GAS: TX status for unexpected destination");
 201                 return;
 202         }
 203
 204         if (result == OFFCHANNEL_SEND_ACTION_SUCCESS) {
 205                 eloop_cancel_timeout(gas_query_timeout, gas, query);
 206                 eloop_register_timeout(GAS_QUERY_TIMEOUT_PERIOD, 0,
 207                                        gas_query_timeout, gas, query);
 208         }
 209         if (result == OFFCHANNEL_SEND_ACTION_FAILED) {
 210                 eloop_cancel_timeout(gas_query_timeout, gas, query);
 211                 eloop_register_timeout(0, 0, gas_query_timeout, gas, query);
 212         }
 213 }
 214
 215
 216 static int gas_query_tx(struct gas_query *gas, struct gas_query_pending *query,
 217                         struct wpabuf *req)
 218 {
 219         int res;
 220         wpa_printf(MSG_DEBUG, "GAS: Send action frame to " MACSTR " len=%u "
 221                    "freq=%d", MAC2STR(query->addr),
 222                    (unsigned int) wpabuf_len(req), query->freq);
 223         res = offchannel_send_action(gas->wpa_s, query->freq, query->addr,
 224                                      gas->wpa_s->own_addr, query->addr,
 225                                      wpabuf_head(req), wpabuf_len(req), 1000,
 226                                      gas_query_tx_status, 0);
 227         if (res == 0)
 228                 query->offchannel_tx_started = 1;
 229         return res;
 230 }
 231
 232
 233 static void gas_query_tx_comeback_req(struct gas_query *gas,
 234                                       struct gas_query_pending *query)
 235 {
 236         struct wpabuf *req;
 237
 238         req = gas_build_comeback_req(query->dialog_token);
 239         if (req == NULL) {
 240                 gas_query_done(gas, query, GAS_QUERY_INTERNAL_ERROR);
 241                 return;
 242         }
 243
 244         if (gas_query_tx(gas, query, req) < 0) {
 245                 wpa_printf(MSG_DEBUG, "GAS: Failed to send Action frame to "
 246                            MACSTR, MAC2STR(query->addr));
 247                 gas_query_done(gas, query, GAS_QUERY_INTERNAL_ERROR);
 248         }
 249
 250         wpabuf_free(req);
 251 }
 252
 253
 254 static void gas_query_tx_comeback_timeout(void *eloop_data, void *user_ctx)
 255 {
 256         struct gas_query *gas = eloop_data;
 257         struct gas_query_pending *query = user_ctx;
 258
 259         wpa_printf(MSG_DEBUG, "GAS: Comeback timeout for request to " MACSTR,
 260                    MAC2STR(query->addr));
 261         gas_query_tx_comeback_req(gas, query);
 262 }
 263
 264
 265 static void gas_query_tx_comeback_req_delay(struct gas_query *gas,
 266                                             struct gas_query_pending *query,
 267                                             u16 comeback_delay)
 268 {
 269         unsigned int secs, usecs;
 270
 271         secs = (comeback_delay * 1024) / 1000000;
 272         usecs = comeback_delay * 1024 - secs * 1000000;
 273         wpa_printf(MSG_DEBUG, "GAS: Send comeback request to " MACSTR
 274                    " in %u secs %u usecs", MAC2STR(query->addr), secs, usecs);
 275         eloop_cancel_timeout(gas_query_tx_comeback_timeout, gas, query);
 276         eloop_register_timeout(secs, usecs, gas_query_tx_comeback_timeout,
 277                                gas, query);
 278 }
 279
 280
 281 static void gas_query_rx_initial(struct gas_query *gas,
 282                                  struct gas_query_pending *query,
 283                                  const u8 *adv_proto, const u8 *resp,
 284                                  size_t len, u16 comeback_delay)
 285 {
 286         wpa_printf(MSG_DEBUG, "GAS: Received initial response from "
 287                    MACSTR " (dialog_token=%u comeback_delay=%u)",
 288                    MAC2STR(query->addr), query->dialog_token, comeback_delay);
 289
 290         query->adv_proto = wpabuf_alloc_copy(adv_proto, 2 + adv_proto[1]);
 291         if (query->adv_proto == NULL) {
 292                 gas_query_done(gas, query, GAS_QUERY_INTERNAL_ERROR);
 293                 return;
 294         }
 295
 296         if (comeback_delay) {
 297                 query->wait_comeback = 1;
 298                 gas_query_tx_comeback_req_delay(gas, query, comeback_delay);
 299                 return;
 300         }
 301
 302         /* Query was completed without comeback mechanism */
 303         if (gas_query_append(query, resp, len) < 0) {
 304                 gas_query_done(gas, query, GAS_QUERY_INTERNAL_ERROR);
 305                 return;
 306         }
 307
 308         gas_query_done(gas, query, GAS_QUERY_SUCCESS);
 309 }
 310
 311
 312 static void gas_query_rx_comeback(struct gas_query *gas,
 313                                   struct gas_query_pending *query,
 314                                   const u8 *adv_proto, const u8 *resp,
 315                                   size_t len, u8 frag_id, u8 more_frags,
 316                                   u16 comeback_delay)
 317 {
 318         wpa_printf(MSG_DEBUG, "GAS: Received comeback response from "
 319                    MACSTR " (dialog_token=%u frag_id=%u more_frags=%u "
 320                    "comeback_delay=%u)",
 321                    MAC2STR(query->addr), query->dialog_token, frag_id,
 322                    more_frags, comeback_delay);
 323
 324         if ((size_t) 2 + adv_proto[1] != wpabuf_len(query->adv_proto) ||
 325             os_memcmp(adv_proto, wpabuf_head(query->adv_proto),
 326                       wpabuf_len(query->adv_proto)) != 0) {
 327                 wpa_printf(MSG_DEBUG, "GAS: Advertisement Protocol changed "
 328                            "between initial and comeback response from "
 329                            MACSTR, MAC2STR(query->addr));
 330                 gas_query_done(gas, query, GAS_QUERY_PEER_ERROR);
 331                 return;
 332         }
 333
 334         if (comeback_delay) {
 335                 if (frag_id) {
 336                         wpa_printf(MSG_DEBUG, "GAS: Invalid comeback response "
 337                                    "with non-zero frag_id and comeback_delay "
 338                                    "from " MACSTR, MAC2STR(query->addr));
 339                         gas_query_done(gas, query, GAS_QUERY_PEER_ERROR);
 340                         return;
 341                 }
 342                 gas_query_tx_comeback_req_delay(gas, query, comeback_delay);
 343                 return;
 344         }
 345
 346         if (frag_id != query->next_frag_id) {
 347                 wpa_printf(MSG_DEBUG, "GAS: Unexpected frag_id in response "
 348                            "from " MACSTR, MAC2STR(query->addr));
 349                 if (frag_id + 1 == query->next_frag_id) {
 350                         wpa_printf(MSG_DEBUG, "GAS: Drop frame as possible "
 351                                    "retry of previous fragment");
 352                         return;
 353                 }
 354                 gas_query_done(gas, query, GAS_QUERY_PEER_ERROR);
 355                 return;
 356         }
 357         query->next_frag_id++;
 358
 359         if (gas_query_append(query, resp, len) < 0) {
 360                 gas_query_done(gas, query, GAS_QUERY_INTERNAL_ERROR);
 361                 return;
 362         }
 363
 364         if (more_frags) {
 365                 gas_query_tx_comeback_req(gas, query);
 366                 return;
 367         }
 368
 369         gas_query_done(gas, query, GAS_QUERY_SUCCESS);
 370 }
 371
 372
 373 /**
 374  * gas_query_rx - Indicate reception of a Public Action frame
 375  * @gas: GAS query data from gas_query_init()
 376  * @da: Destination MAC address of the Action frame
 377  * @sa: Source MAC address of the Action frame
 378  * @bssid: BSSID of the Action frame
 379  * @data: Payload of the Action frame
 380  * @len: Length of @data
 381  * @freq: Frequency (in MHz) on which the frame was received
 382  * Returns: 0 if the Public Action frame was a GAS frame or -1 if not
 383  */
 384 int gas_query_rx(struct gas_query *gas, const u8 *da, const u8 *sa,
 385                  const u8 *bssid, const u8 *data, size_t len, int freq)
 386 {
 387         struct gas_query_pending *query;
 388         u8 action, dialog_token, frag_id = 0, more_frags = 0;
 389         u16 comeback_delay, resp_len;
 390         const u8 *pos, *adv_proto;
 391
 392         if (gas == NULL || len < 4)
 393                 return -1;
 394
 395         pos = data;
 396         action = *pos++;
 397         dialog_token = *pos++;
 398
 399         if (action != WLAN_PA_GAS_INITIAL_RESP &&
 400             action != WLAN_PA_GAS_COMEBACK_RESP)
 401                 return -1; /* Not a GAS response */
 402
 403         query = gas_query_get_pending(gas, sa, dialog_token);
 404         if (query == NULL) {
 405                 wpa_printf(MSG_DEBUG, "GAS: No pending query found for " MACSTR
 406                            " dialog token %u", MAC2STR(sa), dialog_token);
 407                 return -1;
 408         }
 409
 410         if (query->wait_comeback && action == WLAN_PA_GAS_INITIAL_RESP) {
 411                 wpa_printf(MSG_DEBUG, "GAS: Unexpected initial response from "
 412                            MACSTR " dialog token %u when waiting for comeback "
 413                            "response", MAC2STR(sa), dialog_token);
 414                 return 0;
 415         }
 416
 417         if (!query->wait_comeback && action == WLAN_PA_GAS_COMEBACK_RESP) {
 418                 wpa_printf(MSG_DEBUG, "GAS: Unexpected comeback response from "
 419                            MACSTR " dialog token %u when waiting for initial "
 420                            "response", MAC2STR(sa), dialog_token);
 421                 return 0;
 422         }
 423
 424         query->status_code = WPA_GET_LE16(pos);
 425         pos += 2;
 426
 427         if (query->status_code != WLAN_STATUS_SUCCESS) {
 428                 wpa_printf(MSG_DEBUG, "GAS: Query to " MACSTR " dialog token "
 429                            "%u failed - status code %u",
 430                            MAC2STR(sa), dialog_token, query->status_code);
 431                 gas_query_done(gas, query, GAS_QUERY_FAILURE);
 432                 return 0;
 433         }
 434
 435         if (action == WLAN_PA_GAS_COMEBACK_RESP) {
 436                 if (pos + 1 > data + len)
 437                         return 0;
 438                 frag_id = *pos & 0x7f;
 439                 more_frags = (*pos & 0x80) >> 7;
 440                 pos++;
 441         }
 442
 443         /* Comeback Delay */
 444         if (pos + 2 > data + len)
 445                 return 0;
 446         comeback_delay = WPA_GET_LE16(pos);
 447         pos += 2;
 448
 449         /* Advertisement Protocol element */
 450         if (pos + 2 > data + len || pos + 2 + pos[1] > data + len) {
 451                 wpa_printf(MSG_DEBUG, "GAS: No room for Advertisement "
 452                            "Protocol element in the response from " MACSTR,
 453                            MAC2STR(sa));
 454                 return 0;
 455         }
 456
 457         if (*pos != WLAN_EID_ADV_PROTO) {
 458                 wpa_printf(MSG_DEBUG, "GAS: Unexpected Advertisement "
 459                            "Protocol element ID %u in response from " MACSTR,
 460                            *pos, MAC2STR(sa));
 461                 return 0;
 462         }
 463
 464         adv_proto = pos;
 465         pos += 2 + pos[1];
 466
 467         /* Query Response Length */
 468         if (pos + 2 > data + len) {
 469                 wpa_printf(MSG_DEBUG, "GAS: No room for GAS Response Length");
 470                 return 0;
 471         }
 472         resp_len = WPA_GET_LE16(pos);
 473         pos += 2;
 474
 475         if (pos + resp_len > data + len) {
 476                 wpa_printf(MSG_DEBUG, "GAS: Truncated Query Response in "
 477                            "response from " MACSTR, MAC2STR(sa));
 478                 return 0;
 479         }
 480
 481         if (pos + resp_len < data + len) {
 482                 wpa_printf(MSG_DEBUG, "GAS: Ignore %u octets of extra data "
 483                            "after Query Response from " MACSTR,
 484                            (unsigned int) (data + len - pos - resp_len),
 485                            MAC2STR(sa));
 486         }
 487
 488         if (action == WLAN_PA_GAS_COMEBACK_RESP)
 489                 gas_query_rx_comeback(gas, query, adv_proto, pos, resp_len,
 490                                       frag_id, more_frags, comeback_delay);
 491         else
 492                 gas_query_rx_initial(gas, query, adv_proto, pos, resp_len,
 493                                      comeback_delay);
 494
 495         return 0;
 496 }
 497
 498
 499 static void gas_query_timeout(void *eloop_data, void *user_ctx)
 500 {
 501         struct gas_query *gas = eloop_data;
 502         struct gas_query_pending *query = user_ctx;
 503
 504         wpa_printf(MSG_DEBUG, "GAS: No response received for query to " MACSTR
 505                    " dialog token %u",
 506                    MAC2STR(query->addr), query->dialog_token);
 507         gas_query_done(gas, query, GAS_QUERY_TIMEOUT);
 508 }
 509
 510
 511 static void gas_service_timeout(void *eloop_data, void *user_ctx)
 512 {
 513         struct gas_query *gas = eloop_data;
 514         struct wpa_supplicant *wpa_s = gas->wpa_s;
 515         struct gas_query_pending *query = user_ctx;
 516         int conn;
 517
 518         conn = wpas_wpa_is_in_progress(wpa_s, 1);
 519         if (conn || wpa_s->scanning || gas->current) {
 520                 wpa_printf(MSG_DEBUG, "GAS: Delaying GAS query Tx while another operation is in progress:%s%s%s",
 521                            conn ? " connection" : "",
 522                            wpa_s->scanning ? " scanning" : "",
 523                            gas->current ? " gas_query" : "");
 524                 eloop_register_timeout(
 525                         GAS_SERVICE_RETRY_PERIOD_MS / 1000,
 526                         (GAS_SERVICE_RETRY_PERIOD_MS % 1000) * 1000,
 527                         gas_service_timeout, gas, query);
 528                 return;
 529         }
 530
 531         if (gas_query_tx(gas, query, query->req) < 0) {
 532                 wpa_printf(MSG_DEBUG, "GAS: Failed to send Action frame to "
 533                            MACSTR, MAC2STR(query->addr));
 534                 dl_list_del(&query->list);
 535                 wpabuf_free(query->req);
 536                 os_free(query);
 537                 return;
 538         }
 539         gas->current = query;
 540
 541         wpa_printf(MSG_DEBUG, "GAS: Starting query timeout for dialog token %u",
 542                    query->dialog_token);
 543         eloop_register_timeout(GAS_QUERY_TIMEOUT_PERIOD, 0,
 544                                gas_query_timeout, gas, query);
 545 }
 546
 547
 548 static int gas_query_dialog_token_available(struct gas_query *gas,
 549                                             const u8 *dst, u8 dialog_token)
 550 {
 551         struct gas_query_pending *q;
 552         dl_list_for_each(q, &gas->pending, struct gas_query_pending, list) {
 553                 if (os_memcmp(dst, q->addr, ETH_ALEN) == 0 &&
 554                     dialog_token == q->dialog_token)
 555                         return 0;
 556         }
 557
 558         return 1;
 559 }
 560
 561
 562 /**
 563  * gas_query_req - Request a GAS query
 564  * @gas: GAS query data from gas_query_init()
 565  * @dst: Destination MAC address for the query
 566  * @freq: Frequency (in MHz) for the channel on which to send the query
 567  * @req: GAS query payload (to be freed by gas_query module in case of success
 568  *      return)
 569  * @cb: Callback function for reporting GAS query result and response
 570  * @ctx: Context pointer to use with the @cb call
 571  * Returns: dialog token (>= 0) on success or -1 on failure
 572  */
 573 int gas_query_req(struct gas_query *gas, const u8 *dst, int freq,
 574                   struct wpabuf *req,
 575                   void (*cb)(void *ctx, const u8 *dst, u8 dialog_token,
 576                              enum gas_query_result result,
 577                              const struct wpabuf *adv_proto,
 578                              const struct wpabuf *resp, u16 status_code),
 579                   void *ctx)
 580 {
 581         struct gas_query_pending *query;
 582         int dialog_token;
 583         static int next_start = 0;
 584
 585         if (wpabuf_len(req) < 3)
 586                 return -1;
 587
 588         for (dialog_token = 0; dialog_token < 256; dialog_token++) {
 589                 if (gas_query_dialog_token_available(
 590                             gas, dst, (next_start + dialog_token) % 256))
 591                         break;
 592         }
 593         if (dialog_token == 256)
 594                 return -1; /* Too many pending queries */
 595         dialog_token = (next_start + dialog_token) % 256;
 596         next_start = (dialog_token + 1) % 256;
 597
 598         query = os_zalloc(sizeof(*query));
 599         if (query == NULL)
 600                 return -1;
 601
 602         os_memcpy(query->addr, dst, ETH_ALEN);
 603         query->dialog_token = dialog_token;
 604         query->freq = freq;
 605         query->cb = cb;
 606         query->ctx = ctx;
 607         query->req = req;
 608         dl_list_add(&gas->pending, &query->list);
 609
 610         *(wpabuf_mhead_u8(req) + 2) = dialog_token;
 611
 612         wpa_msg(gas->wpa_s, MSG_INFO, GAS_QUERY_START "addr=" MACSTR
 613                 " dialog_token=%u freq=%d",
 614                 MAC2STR(query->addr), query->dialog_token, query->freq);
 615
 616         eloop_register_timeout(0, 0, gas_service_timeout, gas, query);
 617
 618         return dialog_token;
 619 }
 620
 621
 622 /**
 623  * gas_query_cancel - Cancel a pending GAS query
 624  * @gas: GAS query data from gas_query_init()
 625  * @dst: Destination MAC address for the query
 626  * @dialog_token: Dialog token from gas_query_req()
 627  */
 628 void gas_query_cancel(struct gas_query *gas, const u8 *dst, u8 dialog_token)
 629 {
 630         struct gas_query_pending *query;
 631
 632         query = gas_query_get_pending(gas, dst, dialog_token);
 633         if (query)
 634                 gas_query_done(gas, query, GAS_QUERY_CANCELLED);
 635
 636 }
 637
 638
 639 int gas_query_in_progress(struct gas_query *gas)
 640 {
 641         return gas->current != NULL;
 642 }