1 /* 2 * Generic advertisement service (GAS) query (hostapd) 3 * Copyright (c) 2009, Atheros Communications 4 * Copyright (c) 2011-2017, Qualcomm Atheros, Inc. 5 * Copyright (c) 2011-2014, Jouni Malinen <j (at) 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 "utils/list.h" 16 #include "common/ieee802_11_defs.h" 17 #include "common/gas.h" 18 #include "common/wpa_ctrl.h" 19 #include "hostapd.h" 20 #include "sta_info.h" 21 #include "ap_drv_ops.h" 22 #include "gas_query_ap.h" 23 24 25 /** GAS query timeout in seconds */ 26 #define GAS_QUERY_TIMEOUT_PERIOD 2 27 28 /* GAS query wait-time / duration in ms */ 29 #define GAS_QUERY_WAIT_TIME_INITIAL 1000 30 #define GAS_QUERY_WAIT_TIME_COMEBACK 150 31 32 #define GAS_QUERY_MAX_COMEBACK_DELAY 60000 33 34 /** 35 * struct gas_query_pending - Pending GAS query 36 */ 37 struct gas_query_pending { 38 struct dl_list list; 39 struct gas_query_ap *gas; 40 u8 addr[ETH_ALEN]; 41 u8 dialog_token; 42 u8 next_frag_id; 43 unsigned int wait_comeback:1; 44 unsigned int offchannel_tx_started:1; 45 unsigned int retry: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_ap_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_ap - Internal GAS query data 62 */ 63 struct gas_query_ap { 64 struct hostapd_data *hapd; 65 void *msg_ctx; 66 struct dl_list pending; /* struct gas_query_pending */ 67 struct gas_query_pending *current; 68 }; 69 70 71 static void gas_query_tx_comeback_timeout(void *eloop_data, void *user_ctx); 72 static void gas_query_timeout(void *eloop_data, void *user_ctx); 73 static void gas_query_rx_comeback_timeout(void *eloop_data, void *user_ctx); 74 static void gas_query_tx_initial_req(struct gas_query_ap *gas, 75 struct gas_query_pending *query); 76 static int gas_query_new_dialog_token(struct gas_query_ap *gas, const u8 *dst); 77 78 79 static int ms_from_time(struct os_reltime *last) 80 { 81 struct os_reltime now, res; 82 83 os_get_reltime(&now); 84 os_reltime_sub(&now, last, &res); 85 return res.sec * 1000 + res.usec / 1000; 86 } 87 88 89 /** 90 * gas_query_ap_init - Initialize GAS query component 91 * @hapd: Pointer to hostapd data 92 * Returns: Pointer to GAS query data or %NULL on failure 93 */ 94 struct gas_query_ap * gas_query_ap_init(struct hostapd_data *hapd, 95 void *msg_ctx) 96 { 97 struct gas_query_ap *gas; 98 99 gas = os_zalloc(sizeof(*gas)); 100 if (!gas) 101 return NULL; 102 103 gas->hapd = hapd; 104 gas->msg_ctx = msg_ctx; 105 dl_list_init(&gas->pending); 106 107 return gas; 108 } 109 110 111 static const char * gas_result_txt(enum gas_query_ap_result result) 112 { 113 switch (result) { 114 case GAS_QUERY_AP_SUCCESS: 115 return "SUCCESS"; 116 case GAS_QUERY_AP_FAILURE: 117 return "FAILURE"; 118 case GAS_QUERY_AP_TIMEOUT: 119 return "TIMEOUT"; 120 case GAS_QUERY_AP_PEER_ERROR: 121 return "PEER_ERROR"; 122 case GAS_QUERY_AP_INTERNAL_ERROR: 123 return "INTERNAL_ERROR"; 124 case GAS_QUERY_AP_DELETED_AT_DEINIT: 125 return "DELETED_AT_DEINIT"; 126 } 127 128 return "N/A"; 129 } 130 131 132 static void gas_query_free(struct gas_query_pending *query, int del_list) 133 { 134 if (del_list) 135 dl_list_del(&query->list); 136 137 wpabuf_free(query->req); 138 wpabuf_free(query->adv_proto); 139 wpabuf_free(query->resp); 140 os_free(query); 141 } 142 143 144 static void gas_query_done(struct gas_query_ap *gas, 145 struct gas_query_pending *query, 146 enum gas_query_ap_result result) 147 { 148 wpa_msg(gas->msg_ctx, MSG_INFO, GAS_QUERY_DONE "addr=" MACSTR 149 " dialog_token=%u freq=%d status_code=%u result=%s", 150 MAC2STR(query->addr), query->dialog_token, query->freq, 151 query->status_code, gas_result_txt(result)); 152 if (gas->current == query) 153 gas->current = NULL; 154 eloop_cancel_timeout(gas_query_tx_comeback_timeout, gas, query); 155 eloop_cancel_timeout(gas_query_timeout, gas, query); 156 eloop_cancel_timeout(gas_query_rx_comeback_timeout, gas, query); 157 dl_list_del(&query->list); 158 query->cb(query->ctx, query->addr, query->dialog_token, result, 159 query->adv_proto, query->resp, query->status_code); 160 gas_query_free(query, 0); 161 } 162 163 164 /** 165 * gas_query_ap_deinit - Deinitialize GAS query component 166 * @gas: GAS query data from gas_query_init() 167 */ 168 void gas_query_ap_deinit(struct gas_query_ap *gas) 169 { 170 struct gas_query_pending *query, *next; 171 172 if (gas == NULL) 173 return; 174 175 dl_list_for_each_safe(query, next, &gas->pending, 176 struct gas_query_pending, list) 177 gas_query_done(gas, query, GAS_QUERY_AP_DELETED_AT_DEINIT); 178 179 os_free(gas); 180 } 181 182 183 static struct gas_query_pending * 184 gas_query_get_pending(struct gas_query_ap *gas, const u8 *addr, u8 dialog_token) 185 { 186 struct gas_query_pending *q; 187 dl_list_for_each(q, &gas->pending, struct gas_query_pending, list) { 188 if (ether_addr_equal(q->addr, addr) && 189 q->dialog_token == dialog_token) 190 return q; 191 } 192 return NULL; 193 } 194 195 196 static int gas_query_append(struct gas_query_pending *query, const u8 *data, 197 size_t len) 198 { 199 if (wpabuf_resize(&query->resp, len) < 0) { 200 wpa_printf(MSG_DEBUG, "GAS: No memory to store the response"); 201 return -1; 202 } 203 wpabuf_put_data(query->resp, data, len); 204 return 0; 205 } 206 207 208 void gas_query_ap_tx_status(struct gas_query_ap *gas, const u8 *dst, 209 const u8 *data, size_t data_len, int ok) 210 { 211 struct gas_query_pending *query; 212 int dur; 213 214 if (!gas || !gas->current) { 215 wpa_printf(MSG_DEBUG, "GAS: Unexpected TX status: dst=" MACSTR 216 " ok=%d - no query in progress", MAC2STR(dst), ok); 217 return; 218 } 219 220 query = gas->current; 221 222 dur = ms_from_time(&query->last_oper); 223 wpa_printf(MSG_DEBUG, "GAS: TX status: dst=" MACSTR 224 " ok=%d query=%p dialog_token=%u dur=%d ms", 225 MAC2STR(dst), ok, query, query->dialog_token, dur); 226 if (!ether_addr_equal(dst, query->addr)) { 227 wpa_printf(MSG_DEBUG, "GAS: TX status for unexpected destination"); 228 return; 229 } 230 os_get_reltime(&query->last_oper); 231 232 eloop_cancel_timeout(gas_query_timeout, gas, query); 233 if (!ok) { 234 wpa_printf(MSG_DEBUG, "GAS: No ACK to GAS request"); 235 eloop_register_timeout(0, 250000, gas_query_timeout, 236 gas, query); 237 } else { 238 eloop_register_timeout(GAS_QUERY_TIMEOUT_PERIOD, 0, 239 gas_query_timeout, gas, query); 240 } 241 if (query->wait_comeback && !query->retry) { 242 eloop_cancel_timeout(gas_query_rx_comeback_timeout, 243 gas, query); 244 eloop_register_timeout( 245 0, (GAS_QUERY_WAIT_TIME_COMEBACK + 10) * 1000, 246 gas_query_rx_comeback_timeout, gas, query); 247 } 248 } 249 250 251 static int pmf_in_use(struct hostapd_data *hapd, const u8 *addr) 252 { 253 struct sta_info *sta; 254 255 sta = ap_get_sta(hapd, addr); 256 return sta && (sta->flags & WLAN_STA_MFP); 257 } 258 259 260 static int gas_query_tx(struct gas_query_ap *gas, 261 struct gas_query_pending *query, 262 struct wpabuf *req, unsigned int wait_time) 263 { 264 int res, prot = pmf_in_use(gas->hapd, query->addr); 265 266 wpa_printf(MSG_DEBUG, "GAS: Send action frame to " MACSTR " len=%u " 267 "freq=%d prot=%d using src addr " MACSTR, 268 MAC2STR(query->addr), (unsigned int) wpabuf_len(req), 269 query->freq, prot, MAC2STR(query->sa)); 270 if (prot) { 271 u8 *categ = wpabuf_mhead_u8(req); 272 *categ = WLAN_ACTION_PROTECTED_DUAL; 273 } 274 os_get_reltime(&query->last_oper); 275 res = hostapd_drv_send_action(gas->hapd, query->freq, wait_time, 276 query->addr, wpabuf_head(req), 277 wpabuf_len(req)); 278 return res; 279 } 280 281 282 static void gas_query_tx_comeback_req(struct gas_query_ap *gas, 283 struct gas_query_pending *query) 284 { 285 struct wpabuf *req; 286 unsigned int wait_time; 287 288 req = gas_build_comeback_req(query->dialog_token); 289 if (req == NULL) { 290 gas_query_done(gas, query, GAS_QUERY_AP_INTERNAL_ERROR); 291 return; 292 } 293 294 wait_time = (query->retry || !query->offchannel_tx_started) ? 295 GAS_QUERY_WAIT_TIME_INITIAL : GAS_QUERY_WAIT_TIME_COMEBACK; 296 297 if (gas_query_tx(gas, query, req, wait_time) < 0) { 298 wpa_printf(MSG_DEBUG, "GAS: Failed to send Action frame to " 299 MACSTR, MAC2STR(query->addr)); 300 gas_query_done(gas, query, GAS_QUERY_AP_INTERNAL_ERROR); 301 } 302 303 wpabuf_free(req); 304 } 305 306 307 static void gas_query_rx_comeback_timeout(void *eloop_data, void *user_ctx) 308 { 309 struct gas_query_ap *gas = eloop_data; 310 struct gas_query_pending *query = user_ctx; 311 int dialog_token; 312 313 wpa_printf(MSG_DEBUG, 314 "GAS: No response to comeback request received (retry=%u)", 315 query->retry); 316 if (gas->current != query || query->retry) 317 return; 318 dialog_token = gas_query_new_dialog_token(gas, query->addr); 319 if (dialog_token < 0) 320 return; 321 wpa_printf(MSG_DEBUG, 322 "GAS: Retry GAS query due to comeback response timeout"); 323 query->retry = 1; 324 query->dialog_token = dialog_token; 325 *(wpabuf_mhead_u8(query->req) + 2) = dialog_token; 326 query->wait_comeback = 0; 327 query->next_frag_id = 0; 328 wpabuf_free(query->adv_proto); 329 query->adv_proto = NULL; 330 eloop_cancel_timeout(gas_query_tx_comeback_timeout, gas, query); 331 eloop_cancel_timeout(gas_query_timeout, gas, query); 332 gas_query_tx_initial_req(gas, query); 333 } 334 335 336 static void gas_query_tx_comeback_timeout(void *eloop_data, void *user_ctx) 337 { 338 struct gas_query_ap *gas = eloop_data; 339 struct gas_query_pending *query = user_ctx; 340 341 wpa_printf(MSG_DEBUG, "GAS: Comeback timeout for request to " MACSTR, 342 MAC2STR(query->addr)); 343 gas_query_tx_comeback_req(gas, query); 344 } 345 346 347 static void gas_query_tx_comeback_req_delay(struct gas_query_ap *gas, 348 struct gas_query_pending *query, 349 u16 comeback_delay) 350 { 351 unsigned int secs, usecs; 352 353 secs = (comeback_delay * 1024) / 1000000; 354 usecs = comeback_delay * 1024 - secs * 1000000; 355 wpa_printf(MSG_DEBUG, "GAS: Send comeback request to " MACSTR 356 " in %u secs %u usecs", MAC2STR(query->addr), secs, usecs); 357 eloop_cancel_timeout(gas_query_tx_comeback_timeout, gas, query); 358 eloop_register_timeout(secs, usecs, gas_query_tx_comeback_timeout, 359 gas, query); 360 } 361 362 363 static void gas_query_rx_initial(struct gas_query_ap *gas, 364 struct gas_query_pending *query, 365 const u8 *adv_proto, const u8 *resp, 366 size_t len, u16 comeback_delay) 367 { 368 wpa_printf(MSG_DEBUG, "GAS: Received initial response from " 369 MACSTR " (dialog_token=%u comeback_delay=%u)", 370 MAC2STR(query->addr), query->dialog_token, comeback_delay); 371 372 query->adv_proto = wpabuf_alloc_copy(adv_proto, 2 + adv_proto[1]); 373 if (query->adv_proto == NULL) { 374 gas_query_done(gas, query, GAS_QUERY_AP_INTERNAL_ERROR); 375 return; 376 } 377 378 if (comeback_delay) { 379 eloop_cancel_timeout(gas_query_timeout, gas, query); 380 query->wait_comeback = 1; 381 gas_query_tx_comeback_req_delay(gas, query, comeback_delay); 382 return; 383 } 384 385 /* Query was completed without comeback mechanism */ 386 if (gas_query_append(query, resp, len) < 0) { 387 gas_query_done(gas, query, GAS_QUERY_AP_INTERNAL_ERROR); 388 return; 389 } 390 391 gas_query_done(gas, query, GAS_QUERY_AP_SUCCESS); 392 } 393 394 395 static void gas_query_rx_comeback(struct gas_query_ap *gas, 396 struct gas_query_pending *query, 397 const u8 *adv_proto, const u8 *resp, 398 size_t len, u8 frag_id, u8 more_frags, 399 u16 comeback_delay) 400 { 401 wpa_printf(MSG_DEBUG, "GAS: Received comeback response from " 402 MACSTR " (dialog_token=%u frag_id=%u more_frags=%u " 403 "comeback_delay=%u)", 404 MAC2STR(query->addr), query->dialog_token, frag_id, 405 more_frags, comeback_delay); 406 eloop_cancel_timeout(gas_query_rx_comeback_timeout, gas, query); 407 408 if ((size_t) 2 + adv_proto[1] != wpabuf_len(query->adv_proto) || 409 os_memcmp(adv_proto, wpabuf_head(query->adv_proto), 410 wpabuf_len(query->adv_proto)) != 0) { 411 wpa_printf(MSG_DEBUG, "GAS: Advertisement Protocol changed " 412 "between initial and comeback response from " 413 MACSTR, MAC2STR(query->addr)); 414 gas_query_done(gas, query, GAS_QUERY_AP_PEER_ERROR); 415 return; 416 } 417 418 if (comeback_delay) { 419 if (frag_id) { 420 wpa_printf(MSG_DEBUG, "GAS: Invalid comeback response " 421 "with non-zero frag_id and comeback_delay " 422 "from " MACSTR, MAC2STR(query->addr)); 423 gas_query_done(gas, query, GAS_QUERY_AP_PEER_ERROR); 424 return; 425 } 426 gas_query_tx_comeback_req_delay(gas, query, comeback_delay); 427 return; 428 } 429 430 if (frag_id != query->next_frag_id) { 431 wpa_printf(MSG_DEBUG, "GAS: Unexpected frag_id in response " 432 "from " MACSTR, MAC2STR(query->addr)); 433 if (frag_id + 1 == query->next_frag_id) { 434 wpa_printf(MSG_DEBUG, "GAS: Drop frame as possible " 435 "retry of previous fragment"); 436 return; 437 } 438 gas_query_done(gas, query, GAS_QUERY_AP_PEER_ERROR); 439 return; 440 } 441 query->next_frag_id++; 442 443 if (gas_query_append(query, resp, len) < 0) { 444 gas_query_done(gas, query, GAS_QUERY_AP_INTERNAL_ERROR); 445 return; 446 } 447 448 if (more_frags) { 449 gas_query_tx_comeback_req(gas, query); 450 return; 451 } 452 453 gas_query_done(gas, query, GAS_QUERY_AP_SUCCESS); 454 } 455 456 457 /** 458 * gas_query_ap_rx - Indicate reception of a Public Action or Protected Dual 459 * frame 460 * @gas: GAS query data from gas_query_init() 461 * @sa: Source MAC address of the Action frame 462 * @categ: Category of the Action frame 463 * @data: Payload of the Action frame 464 * @len: Length of @data 465 * @freq: Frequency (in MHz) on which the frame was received 466 * Returns: 0 if the Public Action frame was a GAS frame or -1 if not 467 */ 468 int gas_query_ap_rx(struct gas_query_ap *gas, const u8 *sa, u8 categ, 469 const u8 *data, size_t len, int freq) 470 { 471 struct gas_query_pending *query; 472 u8 action, dialog_token, frag_id = 0, more_frags = 0; 473 u16 comeback_delay, resp_len; 474 const u8 *pos, *adv_proto; 475 int prot, pmf; 476 unsigned int left; 477 478 if (!gas || len < 4) 479 return -1; 480 481 pos = data; 482 action = *pos++; 483 dialog_token = *pos++; 484 485 if (action != WLAN_PA_GAS_INITIAL_RESP && 486 action != WLAN_PA_GAS_COMEBACK_RESP) 487 return -1; /* Not a GAS response */ 488 489 prot = categ == WLAN_ACTION_PROTECTED_DUAL; 490 pmf = pmf_in_use(gas->hapd, sa); 491 if (prot && !pmf) { 492 wpa_printf(MSG_DEBUG, "GAS: Drop unexpected protected GAS frame when PMF is disabled"); 493 return 0; 494 } 495 if (!prot && pmf) { 496 wpa_printf(MSG_DEBUG, "GAS: Drop unexpected unprotected GAS frame when PMF is enabled"); 497 return 0; 498 } 499 500 query = gas_query_get_pending(gas, sa, dialog_token); 501 if (query == NULL) { 502 wpa_printf(MSG_DEBUG, "GAS: No pending query found for " MACSTR 503 " dialog token %u", MAC2STR(sa), dialog_token); 504 return -1; 505 } 506 507 wpa_printf(MSG_DEBUG, "GAS: Response in %d ms from " MACSTR, 508 ms_from_time(&query->last_oper), MAC2STR(sa)); 509 510 if (query->wait_comeback && action == WLAN_PA_GAS_INITIAL_RESP) { 511 wpa_printf(MSG_DEBUG, "GAS: Unexpected initial response from " 512 MACSTR " dialog token %u when waiting for comeback " 513 "response", MAC2STR(sa), dialog_token); 514 return 0; 515 } 516 517 if (!query->wait_comeback && action == WLAN_PA_GAS_COMEBACK_RESP) { 518 wpa_printf(MSG_DEBUG, "GAS: Unexpected comeback response from " 519 MACSTR " dialog token %u when waiting for initial " 520 "response", MAC2STR(sa), dialog_token); 521 return 0; 522 } 523 524 query->status_code = WPA_GET_LE16(pos); 525 pos += 2; 526 527 if (query->status_code == WLAN_STATUS_QUERY_RESP_OUTSTANDING && 528 action == WLAN_PA_GAS_COMEBACK_RESP) { 529 wpa_printf(MSG_DEBUG, "GAS: Allow non-zero status for outstanding comeback response"); 530 } else if (query->status_code != WLAN_STATUS_SUCCESS) { 531 wpa_printf(MSG_DEBUG, "GAS: Query to " MACSTR " dialog token " 532 "%u failed - status code %u", 533 MAC2STR(sa), dialog_token, query->status_code); 534 gas_query_done(gas, query, GAS_QUERY_AP_FAILURE); 535 return 0; 536 } 537 538 if (action == WLAN_PA_GAS_COMEBACK_RESP) { 539 if (pos + 1 > data + len) 540 return 0; 541 frag_id = *pos & 0x7f; 542 more_frags = (*pos & 0x80) >> 7; 543 pos++; 544 } 545 546 /* Comeback Delay */ 547 if (pos + 2 > data + len) 548 return 0; 549 comeback_delay = WPA_GET_LE16(pos); 550 if (comeback_delay > GAS_QUERY_MAX_COMEBACK_DELAY) 551 comeback_delay = GAS_QUERY_MAX_COMEBACK_DELAY; 552 pos += 2; 553 554 /* Advertisement Protocol element */ 555 if (pos + 2 > data + len || pos + 2 + pos[1] > data + len) { 556 wpa_printf(MSG_DEBUG, "GAS: No room for Advertisement " 557 "Protocol element in the response from " MACSTR, 558 MAC2STR(sa)); 559 return 0; 560 } 561 562 if (*pos != WLAN_EID_ADV_PROTO) { 563 wpa_printf(MSG_DEBUG, "GAS: Unexpected Advertisement " 564 "Protocol element ID %u in response from " MACSTR, 565 *pos, MAC2STR(sa)); 566 return 0; 567 } 568 569 adv_proto = pos; 570 pos += 2 + pos[1]; 571 572 /* Query Response Length */ 573 if (pos + 2 > data + len) { 574 wpa_printf(MSG_DEBUG, "GAS: No room for GAS Response Length"); 575 return 0; 576 } 577 resp_len = WPA_GET_LE16(pos); 578 pos += 2; 579 580 left = data + len - pos; 581 if (resp_len > left) { 582 wpa_printf(MSG_DEBUG, "GAS: Truncated Query Response in " 583 "response from " MACSTR, MAC2STR(sa)); 584 return 0; 585 } 586 587 if (resp_len < left) { 588 wpa_printf(MSG_DEBUG, "GAS: Ignore %u octets of extra data " 589 "after Query Response from " MACSTR, 590 left - resp_len, MAC2STR(sa)); 591 } 592 593 if (action == WLAN_PA_GAS_COMEBACK_RESP) 594 gas_query_rx_comeback(gas, query, adv_proto, pos, resp_len, 595 frag_id, more_frags, comeback_delay); 596 else 597 gas_query_rx_initial(gas, query, adv_proto, pos, resp_len, 598 comeback_delay); 599 600 return 0; 601 } 602 603 604 static void gas_query_timeout(void *eloop_data, void *user_ctx) 605 { 606 struct gas_query_ap *gas = eloop_data; 607 struct gas_query_pending *query = user_ctx; 608 609 wpa_printf(MSG_DEBUG, "GAS: No response received for query to " MACSTR 610 " dialog token %u", 611 MAC2STR(query->addr), query->dialog_token); 612 gas_query_done(gas, query, GAS_QUERY_AP_TIMEOUT); 613 } 614 615 616 static int gas_query_dialog_token_available(struct gas_query_ap *gas, 617 const u8 *dst, u8 dialog_token) 618 { 619 struct gas_query_pending *q; 620 dl_list_for_each(q, &gas->pending, struct gas_query_pending, list) { 621 if (ether_addr_equal(dst, q->addr) && 622 dialog_token == q->dialog_token) 623 return 0; 624 } 625 626 return 1; 627 } 628 629 630 static void gas_query_tx_initial_req(struct gas_query_ap *gas, 631 struct gas_query_pending *query) 632 { 633 if (gas_query_tx(gas, query, query->req, 634 GAS_QUERY_WAIT_TIME_INITIAL) < 0) { 635 wpa_printf(MSG_DEBUG, "GAS: Failed to send Action frame to " 636 MACSTR, MAC2STR(query->addr)); 637 gas_query_done(gas, query, GAS_QUERY_AP_INTERNAL_ERROR); 638 return; 639 } 640 gas->current = query; 641 642 wpa_printf(MSG_DEBUG, "GAS: Starting query timeout for dialog token %u", 643 query->dialog_token); 644 eloop_register_timeout(GAS_QUERY_TIMEOUT_PERIOD, 0, 645 gas_query_timeout, gas, query); 646 } 647 648 649 static int gas_query_new_dialog_token(struct gas_query_ap *gas, const u8 *dst) 650 { 651 static int next_start = 0; 652 int dialog_token; 653 654 for (dialog_token = 0; dialog_token < 256; dialog_token++) { 655 if (gas_query_dialog_token_available( 656 gas, dst, (next_start + dialog_token) % 256)) 657 break; 658 } 659 if (dialog_token == 256) 660 return -1; /* Too many pending queries */ 661 dialog_token = (next_start + dialog_token) % 256; 662 next_start = (dialog_token + 1) % 256; 663 return dialog_token; 664 } 665 666 667 /** 668 * gas_query_ap_req - Request a GAS query 669 * @gas: GAS query data from gas_query_init() 670 * @dst: Destination MAC address for the query 671 * @freq: Frequency (in MHz) for the channel on which to send the query 672 * @req: GAS query payload (to be freed by gas_query module in case of success 673 * return) 674 * @cb: Callback function for reporting GAS query result and response 675 * @ctx: Context pointer to use with the @cb call 676 * Returns: dialog token (>= 0) on success or -1 on failure 677 */ 678 int gas_query_ap_req(struct gas_query_ap *gas, const u8 *dst, int freq, 679 struct wpabuf *req, 680 void (*cb)(void *ctx, const u8 *dst, u8 dialog_token, 681 enum gas_query_ap_result result, 682 const struct wpabuf *adv_proto, 683 const struct wpabuf *resp, u16 status_code), 684 void *ctx) 685 { 686 struct gas_query_pending *query; 687 int dialog_token; 688 689 if (!gas || wpabuf_len(req) < 3) 690 return -1; 691 692 dialog_token = gas_query_new_dialog_token(gas, dst); 693 if (dialog_token < 0) 694 return -1; 695 696 query = os_zalloc(sizeof(*query)); 697 if (query == NULL) 698 return -1; 699 700 query->gas = gas; 701 os_memcpy(query->addr, dst, ETH_ALEN); 702 query->dialog_token = dialog_token; 703 query->freq = freq; 704 query->cb = cb; 705 query->ctx = ctx; 706 query->req = req; 707 dl_list_add(&gas->pending, &query->list); 708 709 *(wpabuf_mhead_u8(req) + 2) = dialog_token; 710 711 wpa_msg(gas->msg_ctx, MSG_INFO, GAS_QUERY_START "addr=" MACSTR 712 " dialog_token=%u freq=%d", 713 MAC2STR(query->addr), query->dialog_token, query->freq); 714 715 gas_query_tx_initial_req(gas, query); 716 717 return dialog_token; 718 } 719
Indexes created Thu Oct 15 00:24:41 UTC 2026