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 "config.h" 21 #include "driver_i.h" 22 #include "offchannel.h" 23 #include "gas_query.h" 24 25 26 /** GAS query timeout in seconds */ 27 #define GAS_QUERY_TIMEOUT_PERIOD 2 28 29 /* GAS query wait-time / duration in ms */ 30 #define GAS_QUERY_WAIT_TIME_INITIAL 1000 31 #define GAS_QUERY_WAIT_TIME_COMEBACK 150 32 33 /** 34 * struct gas_query_pending - Pending GAS query 35 */ 36 struct gas_query_pending { 37 struct dl_list list; 38 struct gas_query *gas; 39 u8 addr[ETH_ALEN]; 40 u8 dialog_token; 41 u8 next_frag_id; 42 unsigned int wait_comeback:1; 43 unsigned int offchannel_tx_started:1; 44 unsigned int retry:1; 45 unsigned int wildcard_bssid:1; 46 unsigned int maintain_addr:1; 47 int freq; 48 u16 status_code; 49 struct wpabuf *req; 50 struct wpabuf *adv_proto; 51 struct wpabuf *resp; 52 struct os_reltime last_oper; 53 void (*cb)(void *ctx, const u8 *dst, u8 dialog_token, 54 enum gas_query_result result, 55 const struct wpabuf *adv_proto, 56 const struct wpabuf *resp, u16 status_code); 57 void *ctx; 58 u8 sa[ETH_ALEN]; 59 }; 60 61 /** 62 * struct gas_query - Internal GAS query data 63 */ 64 struct gas_query { 65 struct wpa_supplicant *wpa_s; 66 struct dl_list pending; /* struct gas_query_pending */ 67 struct gas_query_pending *current; 68 struct wpa_radio_work *work; 69 struct os_reltime last_mac_addr_rand; 70 int last_rand_sa_type; 71 u8 rand_addr[ETH_ALEN]; 72 }; 73 74 75 static void gas_query_tx_comeback_timeout(void *eloop_data, void *user_ctx); 76 static void gas_query_timeout(void *eloop_data, void *user_ctx); 77 static void gas_query_rx_comeback_timeout(void *eloop_data, void *user_ctx); 78 static void gas_query_tx_initial_req(struct gas_query *gas, 79 struct gas_query_pending *query); 80 static int gas_query_new_dialog_token(struct gas_query *gas, const u8 *dst); 81 82 83 static int ms_from_time(struct os_reltime *last) 84 { 85 struct os_reltime now, res; 86 87 os_get_reltime(&now); 88 os_reltime_sub(&now, last, &res); 89 return res.sec * 1000 + res.usec / 1000; 90 } 91 92 93 /** 94 * gas_query_init - Initialize GAS query component 95 * @wpa_s: Pointer to wpa_supplicant data 96 * Returns: Pointer to GAS query data or %NULL on failure 97 */ 98 struct gas_query * gas_query_init(struct wpa_supplicant *wpa_s) 99 { 100 struct gas_query *gas; 101 102 gas = os_zalloc(sizeof(*gas)); 103 if (gas == NULL) 104 return NULL; 105 106 gas->wpa_s = wpa_s; 107 dl_list_init(&gas->pending); 108 109 return gas; 110 } 111 112 113 static const char * gas_result_txt(enum gas_query_result result) 114 { 115 switch (result) { 116 case GAS_QUERY_SUCCESS: 117 return "SUCCESS"; 118 case GAS_QUERY_FAILURE: 119 return "FAILURE"; 120 case GAS_QUERY_TIMEOUT: 121 return "TIMEOUT"; 122 case GAS_QUERY_PEER_ERROR: 123 return "PEER_ERROR"; 124 case GAS_QUERY_INTERNAL_ERROR: 125 return "INTERNAL_ERROR"; 126 case GAS_QUERY_STOPPED: 127 return "STOPPED"; 128 case GAS_QUERY_DELETED_AT_DEINIT: 129 return "DELETED_AT_DEINIT"; 130 } 131 132 return "N/A"; 133 } 134 135 136 static void gas_query_free(struct gas_query_pending *query, int del_list) 137 { 138 struct gas_query *gas = query->gas; 139 140 if (del_list) 141 dl_list_del(&query->list); 142 143 if (gas->work && gas->work->ctx == query) { 144 radio_work_done(gas->work); 145 gas->work = NULL; 146 } 147 148 wpabuf_free(query->req); 149 wpabuf_free(query->adv_proto); 150 wpabuf_free(query->resp); 151 os_free(query); 152 } 153 154 155 static void gas_query_done(struct gas_query *gas, 156 struct gas_query_pending *query, 157 enum gas_query_result result) 158 { 159 wpa_msg(gas->wpa_s, MSG_INFO, GAS_QUERY_DONE "addr=" MACSTR 160 " dialog_token=%u freq=%d status_code=%u result=%s", 161 MAC2STR(query->addr), query->dialog_token, query->freq, 162 query->status_code, gas_result_txt(result)); 163 if (gas->current == query) 164 gas->current = NULL; 165 if (query->offchannel_tx_started) 166 offchannel_send_action_done(gas->wpa_s); 167 eloop_cancel_timeout(gas_query_tx_comeback_timeout, gas, query); 168 eloop_cancel_timeout(gas_query_timeout, gas, query); 169 eloop_cancel_timeout(gas_query_rx_comeback_timeout, gas, query); 170 dl_list_del(&query->list); 171 query->cb(query->ctx, query->addr, query->dialog_token, result, 172 query->adv_proto, query->resp, query->status_code); 173 gas_query_free(query, 0); 174 } 175 176 177 /** 178 * gas_query_deinit - Deinitialize GAS query component 179 * @gas: GAS query data from gas_query_init() 180 */ 181 void gas_query_deinit(struct gas_query *gas) 182 { 183 struct gas_query_pending *query, *next; 184 185 if (gas == NULL) 186 return; 187 188 dl_list_for_each_safe(query, next, &gas->pending, 189 struct gas_query_pending, list) 190 gas_query_done(gas, query, GAS_QUERY_DELETED_AT_DEINIT); 191 192 os_free(gas); 193 } 194 195 196 static struct gas_query_pending * 197 gas_query_get_pending(struct gas_query *gas, const u8 *addr, u8 dialog_token) 198 { 199 struct gas_query_pending *q; 200 dl_list_for_each(q, &gas->pending, struct gas_query_pending, list) { 201 if (os_memcmp(q->addr, addr, ETH_ALEN) == 0 && 202 q->dialog_token == dialog_token) 203 return q; 204 } 205 return NULL; 206 } 207 208 209 static int gas_query_append(struct gas_query_pending *query, const u8 *data, 210 size_t len) 211 { 212 if (wpabuf_resize(&query->resp, len) < 0) { 213 wpa_printf(MSG_DEBUG, "GAS: No memory to store the response"); 214 return -1; 215 } 216 wpabuf_put_data(query->resp, data, len); 217 return 0; 218 } 219 220 221 static void gas_query_tx_status(struct wpa_supplicant *wpa_s, 222 unsigned int freq, const u8 *dst, 223 const u8 *src, const u8 *bssid, 224 const u8 *data, size_t data_len, 225 enum offchannel_send_action_result result) 226 { 227 struct gas_query_pending *query; 228 struct gas_query *gas = wpa_s->gas; 229 int dur; 230 231 if (gas->current == NULL) { 232 wpa_printf(MSG_DEBUG, "GAS: Unexpected TX status: freq=%u dst=" 233 MACSTR " result=%d - no query in progress", 234 freq, MAC2STR(dst), result); 235 return; 236 } 237 238 query = gas->current; 239 240 dur = ms_from_time(&query->last_oper); 241 wpa_printf(MSG_DEBUG, "GAS: TX status: freq=%u dst=" MACSTR 242 " result=%d query=%p dialog_token=%u dur=%d ms", 243 freq, MAC2STR(dst), result, query, query->dialog_token, dur); 244 if (os_memcmp(dst, query->addr, ETH_ALEN) != 0) { 245 wpa_printf(MSG_DEBUG, "GAS: TX status for unexpected destination"); 246 return; 247 } 248 os_get_reltime(&query->last_oper); 249 250 if (result == OFFCHANNEL_SEND_ACTION_SUCCESS || 251 result == OFFCHANNEL_SEND_ACTION_NO_ACK) { 252 eloop_cancel_timeout(gas_query_timeout, gas, query); 253 if (result == OFFCHANNEL_SEND_ACTION_NO_ACK) { 254 wpa_printf(MSG_DEBUG, "GAS: No ACK to GAS request"); 255 eloop_register_timeout(0, 250000, 256 gas_query_timeout, gas, query); 257 } else { 258 eloop_register_timeout(GAS_QUERY_TIMEOUT_PERIOD, 0, 259 gas_query_timeout, gas, query); 260 } 261 if (query->wait_comeback && !query->retry) { 262 eloop_cancel_timeout(gas_query_rx_comeback_timeout, 263 gas, query); 264 eloop_register_timeout( 265 0, (GAS_QUERY_WAIT_TIME_COMEBACK + 10) * 1000, 266 gas_query_rx_comeback_timeout, gas, query); 267 } 268 } 269 if (result == OFFCHANNEL_SEND_ACTION_FAILED) { 270 eloop_cancel_timeout(gas_query_timeout, gas, query); 271 eloop_register_timeout(0, 0, gas_query_timeout, gas, query); 272 } 273 } 274 275 276 static int gas_query_tx(struct gas_query *gas, struct gas_query_pending *query, 277 struct wpabuf *req, unsigned int wait_time) 278 { 279 int res, prot = pmf_in_use(gas->wpa_s, query->addr); 280 const u8 *bssid; 281 const u8 wildcard_bssid[ETH_ALEN] = { 282 0xff, 0xff, 0xff, 0xff, 0xff, 0xff 283 }; 284 285 wpa_printf(MSG_DEBUG, "GAS: Send action frame to " MACSTR " len=%u " 286 "freq=%d prot=%d using src addr " MACSTR, 287 MAC2STR(query->addr), (unsigned int) wpabuf_len(req), 288 query->freq, prot, MAC2STR(query->sa)); 289 if (prot) { 290 u8 *categ = wpabuf_mhead_u8(req); 291 *categ = WLAN_ACTION_PROTECTED_DUAL; 292 } 293 os_get_reltime(&query->last_oper); 294 if (gas->wpa_s->max_remain_on_chan && 295 wait_time > gas->wpa_s->max_remain_on_chan) 296 wait_time = gas->wpa_s->max_remain_on_chan; 297 if (!query->wildcard_bssid && 298 (!gas->wpa_s->conf->gas_address3 || 299 (gas->wpa_s->current_ssid && 300 gas->wpa_s->wpa_state >= WPA_ASSOCIATED && 301 os_memcmp(query->addr, gas->wpa_s->bssid, ETH_ALEN) == 0))) 302 bssid = query->addr; 303 else 304 bssid = wildcard_bssid; 305 306 res = offchannel_send_action(gas->wpa_s, query->freq, query->addr, 307 query->sa, bssid, wpabuf_head(req), 308 wpabuf_len(req), wait_time, 309 gas_query_tx_status, 0); 310 311 if (res == 0) 312 query->offchannel_tx_started = 1; 313 return res; 314 } 315 316 317 static void gas_query_tx_comeback_req(struct gas_query *gas, 318 struct gas_query_pending *query) 319 { 320 struct wpabuf *req; 321 unsigned int wait_time; 322 323 req = gas_build_comeback_req(query->dialog_token); 324 if (req == NULL) { 325 gas_query_done(gas, query, GAS_QUERY_INTERNAL_ERROR); 326 return; 327 } 328 329 wait_time = (query->retry || !query->offchannel_tx_started) ? 330 GAS_QUERY_WAIT_TIME_INITIAL : GAS_QUERY_WAIT_TIME_COMEBACK; 331 332 if (gas_query_tx(gas, query, req, wait_time) < 0) { 333 wpa_printf(MSG_DEBUG, "GAS: Failed to send Action frame to " 334 MACSTR, MAC2STR(query->addr)); 335 gas_query_done(gas, query, GAS_QUERY_INTERNAL_ERROR); 336 } 337 338 wpabuf_free(req); 339 } 340 341 342 static void gas_query_rx_comeback_timeout(void *eloop_data, void *user_ctx) 343 { 344 struct gas_query *gas = eloop_data; 345 struct gas_query_pending *query = user_ctx; 346 int dialog_token; 347 348 wpa_printf(MSG_DEBUG, 349 "GAS: No response to comeback request received (retry=%u)", 350 query->retry); 351 if (gas->current != query || query->retry) 352 return; 353 dialog_token = gas_query_new_dialog_token(gas, query->addr); 354 if (dialog_token < 0) 355 return; 356 wpa_printf(MSG_DEBUG, 357 "GAS: Retry GAS query due to comeback response timeout"); 358 query->retry = 1; 359 query->dialog_token = dialog_token; 360 *(wpabuf_mhead_u8(query->req) + 2) = dialog_token; 361 query->wait_comeback = 0; 362 query->next_frag_id = 0; 363 wpabuf_free(query->adv_proto); 364 query->adv_proto = NULL; 365 eloop_cancel_timeout(gas_query_tx_comeback_timeout, gas, query); 366 eloop_cancel_timeout(gas_query_timeout, gas, query); 367 gas_query_tx_initial_req(gas, query); 368 } 369 370 371 static void gas_query_tx_comeback_timeout(void *eloop_data, void *user_ctx) 372 { 373 struct gas_query *gas = eloop_data; 374 struct gas_query_pending *query = user_ctx; 375 376 wpa_printf(MSG_DEBUG, "GAS: Comeback timeout for request to " MACSTR, 377 MAC2STR(query->addr)); 378 gas_query_tx_comeback_req(gas, query); 379 } 380 381 382 static void gas_query_tx_comeback_req_delay(struct gas_query *gas, 383 struct gas_query_pending *query, 384 u16 comeback_delay) 385 { 386 unsigned int secs, usecs; 387 388 if (comeback_delay > 1 && query->offchannel_tx_started) { 389 offchannel_send_action_done(gas->wpa_s); 390 query->offchannel_tx_started = 0; 391 } 392 393 secs = (comeback_delay * 1024) / 1000000; 394 usecs = comeback_delay * 1024 - secs * 1000000; 395 wpa_printf(MSG_DEBUG, "GAS: Send comeback request to " MACSTR 396 " in %u secs %u usecs", MAC2STR(query->addr), secs, usecs); 397 eloop_cancel_timeout(gas_query_tx_comeback_timeout, gas, query); 398 eloop_register_timeout(secs, usecs, gas_query_tx_comeback_timeout, 399 gas, query); 400 } 401 402 403 static void gas_query_rx_initial(struct gas_query *gas, 404 struct gas_query_pending *query, 405 const u8 *adv_proto, const u8 *resp, 406 size_t len, u16 comeback_delay) 407 { 408 wpa_printf(MSG_DEBUG, "GAS: Received initial response from " 409 MACSTR " (dialog_token=%u comeback_delay=%u)", 410 MAC2STR(query->addr), query->dialog_token, comeback_delay); 411 412 query->adv_proto = wpabuf_alloc_copy(adv_proto, 2 + adv_proto[1]); 413 if (query->adv_proto == NULL) { 414 gas_query_done(gas, query, GAS_QUERY_INTERNAL_ERROR); 415 return; 416 } 417 418 if (comeback_delay) { 419 eloop_cancel_timeout(gas_query_timeout, gas, query); 420 query->wait_comeback = 1; 421 gas_query_tx_comeback_req_delay(gas, query, comeback_delay); 422 return; 423 } 424 425 /* Query was completed without comeback mechanism */ 426 if (gas_query_append(query, resp, len) < 0) { 427 gas_query_done(gas, query, GAS_QUERY_INTERNAL_ERROR); 428 return; 429 } 430 431 gas_query_done(gas, query, GAS_QUERY_SUCCESS); 432 } 433 434 435 static void gas_query_rx_comeback(struct gas_query *gas, 436 struct gas_query_pending *query, 437 const u8 *adv_proto, const u8 *resp, 438 size_t len, u8 frag_id, u8 more_frags, 439 u16 comeback_delay) 440 { 441 wpa_printf(MSG_DEBUG, "GAS: Received comeback response from " 442 MACSTR " (dialog_token=%u frag_id=%u more_frags=%u " 443 "comeback_delay=%u)", 444 MAC2STR(query->addr), query->dialog_token, frag_id, 445 more_frags, comeback_delay); 446 eloop_cancel_timeout(gas_query_rx_comeback_timeout, gas, query); 447 448 if ((size_t) 2 + adv_proto[1] != wpabuf_len(query->adv_proto) || 449 os_memcmp(adv_proto, wpabuf_head(query->adv_proto), 450 wpabuf_len(query->adv_proto)) != 0) { 451 wpa_printf(MSG_DEBUG, "GAS: Advertisement Protocol changed " 452 "between initial and comeback response from " 453 MACSTR, MAC2STR(query->addr)); 454 gas_query_done(gas, query, GAS_QUERY_PEER_ERROR); 455 return; 456 } 457 458 if (comeback_delay) { 459 if (frag_id) { 460 wpa_printf(MSG_DEBUG, "GAS: Invalid comeback response " 461 "with non-zero frag_id and comeback_delay " 462 "from " MACSTR, MAC2STR(query->addr)); 463 gas_query_done(gas, query, GAS_QUERY_PEER_ERROR); 464 return; 465 } 466 gas_query_tx_comeback_req_delay(gas, query, comeback_delay); 467 return; 468 } 469 470 if (frag_id != query->next_frag_id) { 471 wpa_printf(MSG_DEBUG, "GAS: Unexpected frag_id in response " 472 "from " MACSTR, MAC2STR(query->addr)); 473 if (frag_id + 1 == query->next_frag_id) { 474 wpa_printf(MSG_DEBUG, "GAS: Drop frame as possible " 475 "retry of previous fragment"); 476 return; 477 } 478 gas_query_done(gas, query, GAS_QUERY_PEER_ERROR); 479 return; 480 } 481 query->next_frag_id++; 482 483 if (gas_query_append(query, resp, len) < 0) { 484 gas_query_done(gas, query, GAS_QUERY_INTERNAL_ERROR); 485 return; 486 } 487 488 if (more_frags) { 489 gas_query_tx_comeback_req(gas, query); 490 return; 491 } 492 493 gas_query_done(gas, query, GAS_QUERY_SUCCESS); 494 } 495 496 497 /** 498 * gas_query_rx - Indicate reception of a Public Action or Protected Dual frame 499 * @gas: GAS query data from gas_query_init() 500 * @da: Destination MAC address of the Action frame 501 * @sa: Source MAC address of the Action frame 502 * @bssid: BSSID of the Action frame 503 * @categ: Category of the Action frame 504 * @data: Payload of the Action frame 505 * @len: Length of @data 506 * @freq: Frequency (in MHz) on which the frame was received 507 * Returns: 0 if the Public Action frame was a GAS frame or -1 if not 508 */ 509 int gas_query_rx(struct gas_query *gas, const u8 *da, const u8 *sa, 510 const u8 *bssid, u8 categ, const u8 *data, size_t len, 511 int freq) 512 { 513 struct gas_query_pending *query; 514 u8 action, dialog_token, frag_id = 0, more_frags = 0; 515 u16 comeback_delay, resp_len; 516 const u8 *pos, *adv_proto; 517 int prot, pmf; 518 unsigned int left; 519 520 if (gas == NULL || len < 4) 521 return -1; 522 523 pos = data; 524 action = *pos++; 525 dialog_token = *pos++; 526 527 if (action != WLAN_PA_GAS_INITIAL_RESP && 528 action != WLAN_PA_GAS_COMEBACK_RESP) 529 return -1; /* Not a GAS response */ 530 531 prot = categ == WLAN_ACTION_PROTECTED_DUAL; 532 pmf = pmf_in_use(gas->wpa_s, sa); 533 if (prot && !pmf) { 534 wpa_printf(MSG_DEBUG, "GAS: Drop unexpected protected GAS frame when PMF is disabled"); 535 return 0; 536 } 537 if (!prot && pmf) { 538 wpa_printf(MSG_DEBUG, "GAS: Drop unexpected unprotected GAS frame when PMF is enabled"); 539 return 0; 540 } 541 542 query = gas_query_get_pending(gas, sa, dialog_token); 543 if (query == NULL) { 544 wpa_printf(MSG_DEBUG, "GAS: No pending query found for " MACSTR 545 " dialog token %u", MAC2STR(sa), dialog_token); 546 return -1; 547 } 548 549 wpa_printf(MSG_DEBUG, "GAS: Response in %d ms from " MACSTR, 550 ms_from_time(&query->last_oper), MAC2STR(sa)); 551 552 if (query->wait_comeback && action == WLAN_PA_GAS_INITIAL_RESP) { 553 wpa_printf(MSG_DEBUG, "GAS: Unexpected initial response from " 554 MACSTR " dialog token %u when waiting for comeback " 555 "response", MAC2STR(sa), dialog_token); 556 return 0; 557 } 558 559 if (!query->wait_comeback && action == WLAN_PA_GAS_COMEBACK_RESP) { 560 wpa_printf(MSG_DEBUG, "GAS: Unexpected comeback response from " 561 MACSTR " dialog token %u when waiting for initial " 562 "response", MAC2STR(sa), dialog_token); 563 return 0; 564 } 565 566 query->status_code = WPA_GET_LE16(pos); 567 pos += 2; 568 569 if (query->status_code == WLAN_STATUS_QUERY_RESP_OUTSTANDING && 570 action == WLAN_PA_GAS_COMEBACK_RESP) { 571 wpa_printf(MSG_DEBUG, "GAS: Allow non-zero status for outstanding comeback response"); 572 } else if (query->status_code != WLAN_STATUS_SUCCESS) { 573 wpa_printf(MSG_DEBUG, "GAS: Query to " MACSTR " dialog token " 574 "%u failed - status code %u", 575 MAC2STR(sa), dialog_token, query->status_code); 576 gas_query_done(gas, query, GAS_QUERY_FAILURE); 577 return 0; 578 } 579 580 if (action == WLAN_PA_GAS_COMEBACK_RESP) { 581 if (pos + 1 > data + len) 582 return 0; 583 frag_id = *pos & 0x7f; 584 more_frags = (*pos & 0x80) >> 7; 585 pos++; 586 } 587 588 /* Comeback Delay */ 589 if (pos + 2 > data + len) 590 return 0; 591 comeback_delay = WPA_GET_LE16(pos); 592 pos += 2; 593 594 /* Advertisement Protocol element */ 595 if (pos + 2 > data + len || pos + 2 + pos[1] > data + len) { 596 wpa_printf(MSG_DEBUG, "GAS: No room for Advertisement " 597 "Protocol element in the response from " MACSTR, 598 MAC2STR(sa)); 599 return 0; 600 } 601 602 if (*pos != WLAN_EID_ADV_PROTO) { 603 wpa_printf(MSG_DEBUG, "GAS: Unexpected Advertisement " 604 "Protocol element ID %u in response from " MACSTR, 605 *pos, MAC2STR(sa)); 606 return 0; 607 } 608 609 adv_proto = pos; 610 pos += 2 + pos[1]; 611 612 /* Query Response Length */ 613 if (pos + 2 > data + len) { 614 wpa_printf(MSG_DEBUG, "GAS: No room for GAS Response Length"); 615 return 0; 616 } 617 resp_len = WPA_GET_LE16(pos); 618 pos += 2; 619 620 left = data + len - pos; 621 if (resp_len > left) { 622 wpa_printf(MSG_DEBUG, "GAS: Truncated Query Response in " 623 "response from " MACSTR, MAC2STR(sa)); 624 return 0; 625 } 626 627 if (resp_len < left) { 628 wpa_printf(MSG_DEBUG, "GAS: Ignore %u octets of extra data " 629 "after Query Response from " MACSTR, 630 left - resp_len, MAC2STR(sa)); 631 } 632 633 if (action == WLAN_PA_GAS_COMEBACK_RESP) 634 gas_query_rx_comeback(gas, query, adv_proto, pos, resp_len, 635 frag_id, more_frags, comeback_delay); 636 else 637 gas_query_rx_initial(gas, query, adv_proto, pos, resp_len, 638 comeback_delay); 639 640 return 0; 641 } 642 643 644 static void gas_query_timeout(void *eloop_data, void *user_ctx) 645 { 646 struct gas_query *gas = eloop_data; 647 struct gas_query_pending *query = user_ctx; 648 649 wpa_printf(MSG_DEBUG, "GAS: No response received for query to " MACSTR 650 " dialog token %u", 651 MAC2STR(query->addr), query->dialog_token); 652 gas_query_done(gas, query, GAS_QUERY_TIMEOUT); 653 } 654 655 656 static int gas_query_dialog_token_available(struct gas_query *gas, 657 const u8 *dst, u8 dialog_token) 658 { 659 struct gas_query_pending *q; 660 dl_list_for_each(q, &gas->pending, struct gas_query_pending, list) { 661 if (os_memcmp(dst, q->addr, ETH_ALEN) == 0 && 662 dialog_token == q->dialog_token) 663 return 0; 664 } 665 666 return 1; 667 } 668 669 670 static void gas_query_start_cb(struct wpa_radio_work *work, int deinit) 671 { 672 struct gas_query_pending *query = work->ctx; 673 struct gas_query *gas = query->gas; 674 struct wpa_supplicant *wpa_s = gas->wpa_s; 675 676 if (deinit) { 677 if (work->started) { 678 gas->work = NULL; 679 gas_query_done(gas, query, GAS_QUERY_DELETED_AT_DEINIT); 680 return; 681 } 682 683 gas_query_free(query, 1); 684 return; 685 } 686 687 if (!query->maintain_addr && !wpa_s->conf->gas_rand_mac_addr) { 688 if (wpas_update_random_addr_disassoc(wpa_s) < 0) { 689 wpa_msg(wpa_s, MSG_INFO, 690 "Failed to assign random MAC address for GAS"); 691 gas_query_free(query, 1); 692 radio_work_done(work); 693 return; 694 } 695 os_memcpy(query->sa, wpa_s->own_addr, ETH_ALEN); 696 } 697 698 gas->work = work; 699 gas_query_tx_initial_req(gas, query); 700 } 701 702 703 static void gas_query_tx_initial_req(struct gas_query *gas, 704 struct gas_query_pending *query) 705 { 706 if (gas_query_tx(gas, query, query->req, 707 GAS_QUERY_WAIT_TIME_INITIAL) < 0) { 708 wpa_printf(MSG_DEBUG, "GAS: Failed to send Action frame to " 709 MACSTR, MAC2STR(query->addr)); 710 gas_query_done(gas, query, GAS_QUERY_INTERNAL_ERROR); 711 return; 712 } 713 gas->current = query; 714 715 wpa_printf(MSG_DEBUG, "GAS: Starting query timeout for dialog token %u", 716 query->dialog_token); 717 eloop_register_timeout(GAS_QUERY_TIMEOUT_PERIOD, 0, 718 gas_query_timeout, gas, query); 719 } 720 721 722 static int gas_query_new_dialog_token(struct gas_query *gas, const u8 *dst) 723 { 724 u8 dialog_token; 725 int i; 726 727 /* There should never be more than couple active GAS queries in 728 * progress, so it should be very likely to find an available dialog 729 * token by checking random values. Use a limit on the number of 730 * iterations to handle the unexpected case of large number of pending 731 * queries cleanly. */ 732 for (i = 0; i < 256; i++) { 733 /* Get a random number and check if the slot is available */ 734 if (os_get_random(&dialog_token, sizeof(dialog_token)) < 0) 735 break; 736 if (gas_query_dialog_token_available(gas, dst, dialog_token)) 737 return dialog_token; 738 } 739 740 /* No dialog token value available */ 741 return -1; 742 } 743 744 745 static int gas_query_set_sa(struct gas_query *gas, 746 struct gas_query_pending *query) 747 { 748 struct wpa_supplicant *wpa_s = gas->wpa_s; 749 struct os_reltime now; 750 751 if (query->maintain_addr || 752 !wpa_s->conf->gas_rand_mac_addr || 753 !(wpa_s->current_bss ? 754 (wpa_s->drv_flags & 755 WPA_DRIVER_FLAGS_MGMT_TX_RANDOM_TA_CONNECTED) : 756 (wpa_s->drv_flags & WPA_DRIVER_FLAGS_MGMT_TX_RANDOM_TA))) { 757 /* Use own MAC address as the transmitter address */ 758 wpa_printf(MSG_DEBUG, 759 "GAS: Use own MAC address as the transmitter address%s%s%s", 760 query->maintain_addr ? " (maintain_addr)" : "", 761 !wpa_s->conf->gas_rand_mac_addr ? " (no gas_rand_mac_adr set)" : "", 762 !(wpa_s->current_bss ? 763 (wpa_s->drv_flags & 764 WPA_DRIVER_FLAGS_MGMT_TX_RANDOM_TA_CONNECTED) : 765 (wpa_s->drv_flags & 766 WPA_DRIVER_FLAGS_MGMT_TX_RANDOM_TA)) ? 767 " (no driver rand capa" : ""); 768 os_memcpy(query->sa, wpa_s->own_addr, ETH_ALEN); 769 return 0; 770 } 771 772 os_get_reltime(&now); 773 774 if (wpa_s->conf->gas_rand_mac_addr == gas->last_rand_sa_type && 775 gas->last_mac_addr_rand.sec != 0 && 776 !os_reltime_expired(&now, &gas->last_mac_addr_rand, 777 wpa_s->conf->gas_rand_addr_lifetime)) { 778 wpa_printf(MSG_DEBUG, 779 "GAS: Use the previously selected random transmitter address " 780 MACSTR, MAC2STR(gas->rand_addr)); 781 os_memcpy(query->sa, gas->rand_addr, ETH_ALEN); 782 return 0; 783 } 784 785 if (wpa_s->conf->gas_rand_mac_addr == 1 && 786 random_mac_addr(gas->rand_addr) < 0) { 787 wpa_printf(MSG_ERROR, "GAS: Failed to get random address"); 788 return -1; 789 } 790 791 if (wpa_s->conf->gas_rand_mac_addr == 2 && 792 random_mac_addr_keep_oui(gas->rand_addr) < 0) { 793 wpa_printf(MSG_ERROR, 794 "GAS: Failed to get random address with same OUI"); 795 return -1; 796 } 797 798 wpa_printf(MSG_DEBUG, "GAS: Use a new random transmitter address " 799 MACSTR, MAC2STR(gas->rand_addr)); 800 os_memcpy(query->sa, gas->rand_addr, ETH_ALEN); 801 os_get_reltime(&gas->last_mac_addr_rand); 802 gas->last_rand_sa_type = wpa_s->conf->gas_rand_mac_addr; 803 804 return 0; 805 } 806 807 808 /** 809 * gas_query_req - Request a GAS query 810 * @gas: GAS query data from gas_query_init() 811 * @dst: Destination MAC address for the query 812 * @freq: Frequency (in MHz) for the channel on which to send the query 813 * @wildcard_bssid: Force use of wildcard BSSID value 814 * @maintain_addr: Maintain own MAC address for exchange (i.e., ignore MAC 815 * address randomization rules) 816 * @req: GAS query payload (to be freed by gas_query module in case of success 817 * return) 818 * @cb: Callback function for reporting GAS query result and response 819 * @ctx: Context pointer to use with the @cb call 820 * Returns: dialog token (>= 0) on success or -1 on failure 821 */ 822 int gas_query_req(struct gas_query *gas, const u8 *dst, int freq, 823 int wildcard_bssid, int maintain_addr, struct wpabuf *req, 824 void (*cb)(void *ctx, const u8 *dst, u8 dialog_token, 825 enum gas_query_result result, 826 const struct wpabuf *adv_proto, 827 const struct wpabuf *resp, u16 status_code), 828 void *ctx) 829 { 830 struct gas_query_pending *query; 831 int dialog_token; 832 833 if (wpabuf_len(req) < 3) 834 return -1; 835 836 dialog_token = gas_query_new_dialog_token(gas, dst); 837 if (dialog_token < 0) 838 return -1; 839 840 query = os_zalloc(sizeof(*query)); 841 if (query == NULL) 842 return -1; 843 844 query->gas = gas; 845 query->maintain_addr = !!maintain_addr; 846 if (gas_query_set_sa(gas, query)) { 847 os_free(query); 848 return -1; 849 } 850 os_memcpy(query->addr, dst, ETH_ALEN); 851 query->dialog_token = dialog_token; 852 query->wildcard_bssid = !!wildcard_bssid; 853 query->freq = freq; 854 query->cb = cb; 855 query->ctx = ctx; 856 query->req = req; 857 dl_list_add(&gas->pending, &query->list); 858 859 *(wpabuf_mhead_u8(req) + 2) = dialog_token; 860 861 wpa_msg(gas->wpa_s, MSG_INFO, GAS_QUERY_START "addr=" MACSTR 862 " dialog_token=%u freq=%d", 863 MAC2STR(query->addr), query->dialog_token, query->freq); 864 865 if (radio_add_work(gas->wpa_s, freq, "gas-query", 0, gas_query_start_cb, 866 query) < 0) { 867 query->req = NULL; /* caller will free this in error case */ 868 gas_query_free(query, 1); 869 return -1; 870 } 871 872 return dialog_token; 873 } 874 875 876 int gas_query_stop(struct gas_query *gas, u8 dialog_token) 877 { 878 struct gas_query_pending *query; 879 880 dl_list_for_each(query, &gas->pending, struct gas_query_pending, list) { 881 if (query->dialog_token == dialog_token) { 882 if (!gas->work) { 883 /* The pending radio work has not yet been 884 * started, but the pending entry has a 885 * reference to the soon to be freed query. 886 * Need to remove that radio work now to avoid 887 * leaving behind a reference to freed memory. 888 */ 889 radio_remove_pending_work(gas->wpa_s, query); 890 } 891 gas_query_done(gas, query, GAS_QUERY_STOPPED); 892 return 0; 893 } 894 } 895 896 return -1; 897 } 898