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 29 /** 30 * struct gas_query_pending - Pending GAS query 31 */ 32 struct gas_query_pending { 33 struct dl_list list; 34 struct gas_query *gas; 35 u8 addr[ETH_ALEN]; 36 u8 dialog_token; 37 u8 next_frag_id; 38 unsigned int wait_comeback:1; 39 unsigned int offchannel_tx_started:1; 40 int freq; 41 u16 status_code; 42 struct wpabuf *req; 43 struct wpabuf *adv_proto; 44 struct wpabuf *resp; 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); 50 void *ctx; 51 }; 52 53 /** 54 * struct gas_query - Internal GAS query data 55 */ 56 struct gas_query { 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; 61 }; 62 63 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); 66 67 68 static int ms_from_time(struct os_reltime *last) 69 { 70 struct os_reltime now, res; 71 72 os_get_reltime(&now); 73 os_reltime_sub(&now, last, &res); 74 return res.sec * 1000 + res.usec / 1000; 75 } 76 77 78 /** 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 82 */ 83 struct gas_query * gas_query_init(struct wpa_supplicant *wpa_s) 84 { 85 struct gas_query *gas; 86 87 gas = os_zalloc(sizeof(*gas)); 88 if (gas == NULL) 89 return NULL; 90 91 gas->wpa_s = wpa_s; 92 dl_list_init(&gas->pending); 93 94 return gas; 95 } 96 97 98 static const char * gas_result_txt(enum gas_query_result result) 99 { 100 switch (result) { 101 case GAS_QUERY_SUCCESS: 102 return "SUCCESS"; 103 case GAS_QUERY_FAILURE: 104 return "FAILURE"; 105 case GAS_QUERY_TIMEOUT: 106 return "TIMEOUT"; 107 case GAS_QUERY_PEER_ERROR: 108 return "PEER_ERROR"; 109 case GAS_QUERY_INTERNAL_ERROR: 110 return "INTERNAL_ERROR"; 111 case GAS_QUERY_CANCELLED: 112 return "CANCELLED"; 113 case GAS_QUERY_DELETED_AT_DEINIT: 114 return "DELETED_AT_DEINIT"; 115 } 116 117 return "N/A"; 118 } 119 120 121 static void gas_query_free(struct gas_query_pending *query, int del_list) 122 { 123 struct gas_query *gas = query->gas; 124 125 if (del_list) 126 dl_list_del(&query->list); 127 128 if (gas->work && gas->work->ctx == query) { 129 radio_work_done(gas->work); 130 gas->work = NULL; 131 } 132 133 wpabuf_free(query->req); 134 wpabuf_free(query->adv_proto); 135 wpabuf_free(query->resp); 136 os_free(query); 137 } 138 139 140 static void gas_query_done(struct gas_query *gas, 141 struct gas_query_pending *query, 142 enum gas_query_result result) 143 { 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) 149 gas->current = NULL; 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); 158 } 159 160 161 /** 162 * gas_query_deinit - Deinitialize GAS query component 163 * @gas: GAS query data from gas_query_init() 164 */ 165 void gas_query_deinit(struct gas_query *gas) 166 { 167 struct gas_query_pending *query, *next; 168 169 if (gas == NULL) 170 return; 171 172 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); 175 176 os_free(gas); 177 } 178 179 180 static struct gas_query_pending * 181 gas_query_get_pending(struct gas_query *gas, const u8 *addr, u8 dialog_token) 182 { 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) 187 return q; 188 } 189 return NULL; 190 } 191 192 193 static int gas_query_append(struct gas_query_pending *query, const u8 *data, 194 size_t len) 195 { 196 if (wpabuf_resize(&query->resp, len) < 0) { 197 wpa_printf(MSG_DEBUG, "GAS: No memory to store the response"); 198 return -1; 199 } 200 wpabuf_put_data(query->resp, data, len); 201 return 0; 202 } 203 204 205 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) 210 { 211 struct gas_query_pending *query; 212 struct gas_query *gas = wpa_s->gas; 213 int dur; 214 215 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); 219 return; 220 } 221 222 query = gas->current; 223 224 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"); 230 return; 231 } 232 os_get_reltime(&query->last_oper); 233 234 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); 238 } 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); 242 } 243 } 244 245 246 static int pmf_in_use(struct wpa_supplicant *wpa_s, const u8 *addr) 247 { 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) 251 return 0; 252 return wpa_sm_pmf_enabled(wpa_s->wpa); 253 } 254 255 256 static int gas_query_tx(struct gas_query *gas, struct gas_query_pending *query, 257 struct wpabuf *req) 258 { 259 unsigned int wait_time; 260 int res, prot = pmf_in_use(gas->wpa_s, query->addr); 261 262 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); 265 if (prot) { 266 u8 *categ = wpabuf_mhead_u8(req); 267 *categ = WLAN_ACTION_PROTECTED_DUAL; 268 } 269 os_get_reltime(&query->last_oper); 270 wait_time = 1000; 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); 278 if (res == 0) 279 query->offchannel_tx_started = 1; 280 return res; 281 } 282 283 284 static void gas_query_tx_comeback_req(struct gas_query *gas, 285 struct gas_query_pending *query) 286 { 287 struct wpabuf *req; 288 289 req = gas_build_comeback_req(query->dialog_token); 290 if (req == NULL) { 291 gas_query_done(gas, query, GAS_QUERY_INTERNAL_ERROR); 292 return; 293 } 294 295 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); 299 } 300 301 wpabuf_free(req); 302 } 303 304 305 static void gas_query_tx_comeback_timeout(void *eloop_data, void *user_ctx) 306 { 307 struct gas_query *gas = eloop_data; 308 struct gas_query_pending *query = user_ctx; 309 310 wpa_printf(MSG_DEBUG, "GAS: Comeback timeout for request to " MACSTR, 311 MAC2STR(query->addr)); 312 gas_query_tx_comeback_req(gas, query); 313 } 314 315 316 static void gas_query_tx_comeback_req_delay(struct gas_query *gas, 317 struct gas_query_pending *query, 318 u16 comeback_delay) 319 { 320 unsigned int secs, usecs; 321 322 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, 328 gas, query); 329 } 330 331 332 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) 336 { 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); 340 341 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); 344 return; 345 } 346 347 if (comeback_delay) { 348 query->wait_comeback = 1; 349 gas_query_tx_comeback_req_delay(gas, query, comeback_delay); 350 return; 351 } 352 353 /* 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); 356 return; 357 } 358 359 gas_query_done(gas, query, GAS_QUERY_SUCCESS); 360 } 361 362 363 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, 367 u16 comeback_delay) 368 { 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); 374 375 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); 382 return; 383 } 384 385 if (comeback_delay) { 386 if (frag_id) { 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); 391 return; 392 } 393 gas_query_tx_comeback_req_delay(gas, query, comeback_delay); 394 return; 395 } 396 397 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"); 403 return; 404 } 405 gas_query_done(gas, query, GAS_QUERY_PEER_ERROR); 406 return; 407 } 408 query->next_frag_id++; 409 410 if (gas_query_append(query, resp, len) < 0) { 411 gas_query_done(gas, query, GAS_QUERY_INTERNAL_ERROR); 412 return; 413 } 414 415 if (more_frags) { 416 gas_query_tx_comeback_req(gas, query); 417 return; 418 } 419 420 gas_query_done(gas, query, GAS_QUERY_SUCCESS); 421 } 422 423 424 /** 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 435 */ 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, 438 int freq) 439 { 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; 444 int prot, pmf; 445 unsigned int left; 446 447 if (gas == NULL || len < 4) 448 return -1; 449 450 prot = categ == WLAN_ACTION_PROTECTED_DUAL; 451 pmf = pmf_in_use(gas->wpa_s, bssid); 452 if (prot && !pmf) { 453 wpa_printf(MSG_DEBUG, "GAS: Drop unexpected protected GAS frame when PMF is disabled"); 454 return 0; 455 } 456 if (!prot && pmf) { 457 wpa_printf(MSG_DEBUG, "GAS: Drop unexpected unprotected GAS frame when PMF is enabled"); 458 return 0; 459 } 460 461 pos = data; 462 action = *pos++; 463 dialog_token = *pos++; 464 465 if (action != WLAN_PA_GAS_INITIAL_RESP && 466 action != WLAN_PA_GAS_COMEBACK_RESP) 467 return -1; /* Not a GAS response */ 468 469 query = gas_query_get_pending(gas, sa, dialog_token); 470 if (query == NULL) { 471 wpa_printf(MSG_DEBUG, "GAS: No pending query found for " MACSTR 472 " dialog token %u", MAC2STR(sa), dialog_token); 473 return -1; 474 } 475 476 wpa_printf(MSG_DEBUG, "GAS: Response in %d ms from " MACSTR, 477 ms_from_time(&query->last_oper), MAC2STR(sa)); 478 479 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); 483 return 0; 484 } 485 486 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); 490 return 0; 491 } 492 493 query->status_code = WPA_GET_LE16(pos); 494 pos += 2; 495 496 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); 504 return 0; 505 } 506 507 if (action == WLAN_PA_GAS_COMEBACK_RESP) { 508 if (pos + 1 > data + len) 509 return 0; 510 frag_id = *pos & 0x7f; 511 more_frags = (*pos & 0x80) >> 7; 512 pos++; 513 } 514 515 /* Comeback Delay */ 516 if (pos + 2 > data + len) 517 return 0; 518 comeback_delay = WPA_GET_LE16(pos); 519 pos += 2; 520 521 /* 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, 525 MAC2STR(sa)); 526 return 0; 527 } 528 529 if (*pos != WLAN_EID_ADV_PROTO) { 530 wpa_printf(MSG_DEBUG, "GAS: Unexpected Advertisement " 531 "Protocol element ID %u in response from " MACSTR, 532 *pos, MAC2STR(sa)); 533 return 0; 534 } 535 536 adv_proto = pos; 537 pos += 2 + pos[1]; 538 539 /* Query Response Length */ 540 if (pos + 2 > data + len) { 541 wpa_printf(MSG_DEBUG, "GAS: No room for GAS Response Length"); 542 return 0; 543 } 544 resp_len = WPA_GET_LE16(pos); 545 pos += 2; 546 547 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)); 551 return 0; 552 } 553 554 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)); 558 } 559 560 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); 563 else 564 gas_query_rx_initial(gas, query, adv_proto, pos, resp_len, 565 comeback_delay); 566 567 return 0; 568 } 569 570 571 static void gas_query_timeout(void *eloop_data, void *user_ctx) 572 { 573 struct gas_query *gas = eloop_data; 574 struct gas_query_pending *query = user_ctx; 575 576 wpa_printf(MSG_DEBUG, "GAS: No response received for query to " MACSTR 577 " dialog token %u", 578 MAC2STR(query->addr), query->dialog_token); 579 gas_query_done(gas, query, GAS_QUERY_TIMEOUT); 580 } 581 582 583 static int gas_query_dialog_token_available(struct gas_query *gas, 584 const u8 *dst, u8 dialog_token) 585 { 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) 590 return 0; 591 } 592 593 return 1; 594 } 595 596 597 static void gas_query_start_cb(struct wpa_radio_work *work, int deinit) 598 { 599 struct gas_query_pending *query = work->ctx; 600 struct gas_query *gas = query->gas; 601 struct wpa_supplicant *wpa_s = gas->wpa_s; 602 603 if (deinit) { 604 if (work->started) { 605 gas->work = NULL; 606 gas_query_done(gas, query, GAS_QUERY_DELETED_AT_DEINIT); 607 return; 608 } 609 610 gas_query_free(query, 1); 611 return; 612 } 613 614 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); 619 return; 620 } 621 622 gas->work = work; 623 624 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); 628 return; 629 } 630 gas->current = query; 631 632 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); 636 637 } 638 639 640 /** 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 646 * return) 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 650 */ 651 int gas_query_req(struct gas_query *gas, const u8 *dst, int freq, 652 struct wpabuf *req, 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), 657 void *ctx) 658 { 659 struct gas_query_pending *query; 660 int dialog_token; 661 static int next_start = 0; 662 663 if (wpabuf_len(req) < 3) 664 return -1; 665 666 for (dialog_token = 0; dialog_token < 256; dialog_token++) { 667 if (gas_query_dialog_token_available( 668 gas, dst, (next_start + dialog_token) % 256)) 669 break; 670 } 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; 675 676 query = os_zalloc(sizeof(*query)); 677 if (query == NULL) 678 return -1; 679 680 query->gas = gas; 681 os_memcpy(query->addr, dst, ETH_ALEN); 682 query->dialog_token = dialog_token; 683 query->freq = freq; 684 query->cb = cb; 685 query->ctx = ctx; 686 query->req = req; 687 dl_list_add(&gas->pending, &query->list); 688 689 *(wpabuf_mhead_u8(req) + 2) = dialog_token; 690 691 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); 694 695 if (radio_add_work(gas->wpa_s, freq, "gas-query", 0, gas_query_start_cb, 696 query) < 0) { 697 gas_query_free(query, 1); 698 return -1; 699 } 700 701 return dialog_token; 702 } 703 704 705 /** 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() 710 */ 711 void gas_query_cancel(struct gas_query *gas, const u8 *dst, u8 dialog_token) 712 { 713 struct gas_query_pending *query; 714 715 query = gas_query_get_pending(gas, dst, dialog_token); 716 if (query) 717 gas_query_done(gas, query, GAS_QUERY_CANCELLED); 718 719 } 720