1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * cfg80211 scan result handling 4 * 5 * Copyright 2008 Johannes Berg <johannes@sipsolutions.net> 6 * Copyright 2013-2014 Intel Mobile Communications GmbH 7 * Copyright 2016 Intel Deutschland GmbH 8 * Copyright (C) 2018-2021 Intel Corporation 9 */ 10 #include <linux/kernel.h> 11 #include <linux/slab.h> 12 #include <linux/module.h> 13 #include <linux/netdevice.h> 14 #include <linux/wireless.h> 15 #include <linux/nl80211.h> 16 #include <linux/etherdevice.h> 17 #include <linux/crc32.h> 18 #include <linux/bitfield.h> 19 #include <net/arp.h> 20 #include <net/cfg80211.h> 21 #include <net/cfg80211-wext.h> 22 #include <net/iw_handler.h> 23 #include "core.h" 24 #include "nl80211.h" 25 #include "wext-compat.h" 26 #include "rdev-ops.h" 27 28 /** 29 * DOC: BSS tree/list structure 30 * 31 * At the top level, the BSS list is kept in both a list in each 32 * registered device (@bss_list) as well as an RB-tree for faster 33 * lookup. In the RB-tree, entries can be looked up using their 34 * channel, MESHID, MESHCONF (for MBSSes) or channel, BSSID, SSID 35 * for other BSSes. 36 * 37 * Due to the possibility of hidden SSIDs, there's a second level 38 * structure, the "hidden_list" and "hidden_beacon_bss" pointer. 39 * The hidden_list connects all BSSes belonging to a single AP 40 * that has a hidden SSID, and connects beacon and probe response 41 * entries. For a probe response entry for a hidden SSID, the 42 * hidden_beacon_bss pointer points to the BSS struct holding the 43 * beacon's information. 44 * 45 * Reference counting is done for all these references except for 46 * the hidden_list, so that a beacon BSS struct that is otherwise 47 * not referenced has one reference for being on the bss_list and 48 * one for each probe response entry that points to it using the 49 * hidden_beacon_bss pointer. When a BSS struct that has such a 50 * pointer is get/put, the refcount update is also propagated to 51 * the referenced struct, this ensure that it cannot get removed 52 * while somebody is using the probe response version. 53 * 54 * Note that the hidden_beacon_bss pointer never changes, due to 55 * the reference counting. Therefore, no locking is needed for 56 * it. 57 * 58 * Also note that the hidden_beacon_bss pointer is only relevant 59 * if the driver uses something other than the IEs, e.g. private 60 * data stored in the BSS struct, since the beacon IEs are 61 * also linked into the probe response struct. 62 */ 63 64 /* 65 * Limit the number of BSS entries stored in mac80211. Each one is 66 * a bit over 4k at most, so this limits to roughly 4-5M of memory. 67 * If somebody wants to really attack this though, they'd likely 68 * use small beacons, and only one type of frame, limiting each of 69 * the entries to a much smaller size (in order to generate more 70 * entries in total, so overhead is bigger.) 71 */ 72 static int bss_entries_limit = 1000; 73 module_param(bss_entries_limit, int, 0644); 74 MODULE_PARM_DESC(bss_entries_limit, 75 "limit to number of scan BSS entries (per wiphy, default 1000)"); 76 77 #define IEEE80211_SCAN_RESULT_EXPIRE (30 * HZ) 78 79 /** 80 * struct cfg80211_colocated_ap - colocated AP information 81 * 82 * @list: linked list to all colocated aPS 83 * @bssid: BSSID of the reported AP 84 * @ssid: SSID of the reported AP 85 * @ssid_len: length of the ssid 86 * @center_freq: frequency the reported AP is on 87 * @unsolicited_probe: the reported AP is part of an ESS, where all the APs 88 * that operate in the same channel as the reported AP and that might be 89 * detected by a STA receiving this frame, are transmitting unsolicited 90 * Probe Response frames every 20 TUs 91 * @oct_recommended: OCT is recommended to exchange MMPDUs with the reported AP 92 * @same_ssid: the reported AP has the same SSID as the reporting AP 93 * @multi_bss: the reported AP is part of a multiple BSSID set 94 * @transmitted_bssid: the reported AP is the transmitting BSSID 95 * @colocated_ess: all the APs that share the same ESS as the reported AP are 96 * colocated and can be discovered via legacy bands. 97 * @short_ssid_valid: short_ssid is valid and can be used 98 * @short_ssid: the short SSID for this SSID 99 */ 100 struct cfg80211_colocated_ap { 101 struct list_head list; 102 u8 bssid[ETH_ALEN]; 103 u8 ssid[IEEE80211_MAX_SSID_LEN]; 104 size_t ssid_len; 105 u32 short_ssid; 106 u32 center_freq; 107 u8 unsolicited_probe:1, 108 oct_recommended:1, 109 same_ssid:1, 110 multi_bss:1, 111 transmitted_bssid:1, 112 colocated_ess:1, 113 short_ssid_valid:1; 114 }; 115 116 static void bss_free(struct cfg80211_internal_bss *bss) 117 { 118 struct cfg80211_bss_ies *ies; 119 120 if (WARN_ON(atomic_read(&bss->hold))) 121 return; 122 123 ies = (void *)rcu_access_pointer(bss->pub.beacon_ies); 124 if (ies && !bss->pub.hidden_beacon_bss) 125 kfree_rcu(ies, rcu_head); 126 ies = (void *)rcu_access_pointer(bss->pub.proberesp_ies); 127 if (ies) 128 kfree_rcu(ies, rcu_head); 129 130 /* 131 * This happens when the module is removed, it doesn't 132 * really matter any more save for completeness 133 */ 134 if (!list_empty(&bss->hidden_list)) 135 list_del(&bss->hidden_list); 136 137 kfree(bss); 138 } 139 140 static inline void bss_ref_get(struct cfg80211_registered_device *rdev, 141 struct cfg80211_internal_bss *bss) 142 { 143 lockdep_assert_held(&rdev->bss_lock); 144 145 bss->refcount++; 146 if (bss->pub.hidden_beacon_bss) { 147 bss = container_of(bss->pub.hidden_beacon_bss, 148 struct cfg80211_internal_bss, 149 pub); 150 bss->refcount++; 151 } 152 if (bss->pub.transmitted_bss) { 153 bss = container_of(bss->pub.transmitted_bss, 154 struct cfg80211_internal_bss, 155 pub); 156 bss->refcount++; 157 } 158 } 159 160 static inline void bss_ref_put(struct cfg80211_registered_device *rdev, 161 struct cfg80211_internal_bss *bss) 162 { 163 lockdep_assert_held(&rdev->bss_lock); 164 165 if (bss->pub.hidden_beacon_bss) { 166 struct cfg80211_internal_bss *hbss; 167 hbss = container_of(bss->pub.hidden_beacon_bss, 168 struct cfg80211_internal_bss, 169 pub); 170 hbss->refcount--; 171 if (hbss->refcount == 0) 172 bss_free(hbss); 173 } 174 175 if (bss->pub.transmitted_bss) { 176 struct cfg80211_internal_bss *tbss; 177 178 tbss = container_of(bss->pub.transmitted_bss, 179 struct cfg80211_internal_bss, 180 pub); 181 tbss->refcount--; 182 if (tbss->refcount == 0) 183 bss_free(tbss); 184 } 185 186 bss->refcount--; 187 if (bss->refcount == 0) 188 bss_free(bss); 189 } 190 191 static bool __cfg80211_unlink_bss(struct cfg80211_registered_device *rdev, 192 struct cfg80211_internal_bss *bss) 193 { 194 lockdep_assert_held(&rdev->bss_lock); 195 196 if (!list_empty(&bss->hidden_list)) { 197 /* 198 * don't remove the beacon entry if it has 199 * probe responses associated with it 200 */ 201 if (!bss->pub.hidden_beacon_bss) 202 return false; 203 /* 204 * if it's a probe response entry break its 205 * link to the other entries in the group 206 */ 207 list_del_init(&bss->hidden_list); 208 } 209 210 list_del_init(&bss->list); 211 list_del_init(&bss->pub.nontrans_list); 212 rb_erase(&bss->rbn, &rdev->bss_tree); 213 rdev->bss_entries--; 214 WARN_ONCE((rdev->bss_entries == 0) ^ list_empty(&rdev->bss_list), 215 "rdev bss entries[%d]/list[empty:%d] corruption\n", 216 rdev->bss_entries, list_empty(&rdev->bss_list)); 217 bss_ref_put(rdev, bss); 218 return true; 219 } 220 221 bool cfg80211_is_element_inherited(const struct element *elem, 222 const struct element *non_inherit_elem) 223 { 224 u8 id_len, ext_id_len, i, loop_len, id; 225 const u8 *list; 226 227 if (elem->id == WLAN_EID_MULTIPLE_BSSID) 228 return false; 229 230 if (!non_inherit_elem || non_inherit_elem->datalen < 2) 231 return true; 232 233 /* 234 * non inheritance element format is: 235 * ext ID (56) | IDs list len | list | extension IDs list len | list 236 * Both lists are optional. Both lengths are mandatory. 237 * This means valid length is: 238 * elem_len = 1 (extension ID) + 2 (list len fields) + list lengths 239 */ 240 id_len = non_inherit_elem->data[1]; 241 if (non_inherit_elem->datalen < 3 + id_len) 242 return true; 243 244 ext_id_len = non_inherit_elem->data[2 + id_len]; 245 if (non_inherit_elem->datalen < 3 + id_len + ext_id_len) 246 return true; 247 248 if (elem->id == WLAN_EID_EXTENSION) { 249 if (!ext_id_len) 250 return true; 251 loop_len = ext_id_len; 252 list = &non_inherit_elem->data[3 + id_len]; 253 id = elem->data[0]; 254 } else { 255 if (!id_len) 256 return true; 257 loop_len = id_len; 258 list = &non_inherit_elem->data[2]; 259 id = elem->id; 260 } 261 262 for (i = 0; i < loop_len; i++) { 263 if (list[i] == id) 264 return false; 265 } 266 267 return true; 268 } 269 EXPORT_SYMBOL(cfg80211_is_element_inherited); 270 271 static size_t cfg80211_gen_new_ie(const u8 *ie, size_t ielen, 272 const u8 *subelement, size_t subie_len, 273 u8 *new_ie, gfp_t gfp) 274 { 275 u8 *pos, *tmp; 276 const u8 *tmp_old, *tmp_new; 277 const struct element *non_inherit_elem; 278 u8 *sub_copy; 279 280 /* copy subelement as we need to change its content to 281 * mark an ie after it is processed. 282 */ 283 sub_copy = kmemdup(subelement, subie_len, gfp); 284 if (!sub_copy) 285 return 0; 286 287 pos = &new_ie[0]; 288 289 /* set new ssid */ 290 tmp_new = cfg80211_find_ie(WLAN_EID_SSID, sub_copy, subie_len); 291 if (tmp_new) { 292 memcpy(pos, tmp_new, tmp_new[1] + 2); 293 pos += (tmp_new[1] + 2); 294 } 295 296 /* get non inheritance list if exists */ 297 non_inherit_elem = 298 cfg80211_find_ext_elem(WLAN_EID_EXT_NON_INHERITANCE, 299 sub_copy, subie_len); 300 301 /* go through IEs in ie (skip SSID) and subelement, 302 * merge them into new_ie 303 */ 304 tmp_old = cfg80211_find_ie(WLAN_EID_SSID, ie, ielen); 305 tmp_old = (tmp_old) ? tmp_old + tmp_old[1] + 2 : ie; 306 307 while (tmp_old + tmp_old[1] + 2 - ie <= ielen) { 308 if (tmp_old[0] == 0) { 309 tmp_old++; 310 continue; 311 } 312 313 if (tmp_old[0] == WLAN_EID_EXTENSION) 314 tmp = (u8 *)cfg80211_find_ext_ie(tmp_old[2], sub_copy, 315 subie_len); 316 else 317 tmp = (u8 *)cfg80211_find_ie(tmp_old[0], sub_copy, 318 subie_len); 319 320 if (!tmp) { 321 const struct element *old_elem = (void *)tmp_old; 322 323 /* ie in old ie but not in subelement */ 324 if (cfg80211_is_element_inherited(old_elem, 325 non_inherit_elem)) { 326 memcpy(pos, tmp_old, tmp_old[1] + 2); 327 pos += tmp_old[1] + 2; 328 } 329 } else { 330 /* ie in transmitting ie also in subelement, 331 * copy from subelement and flag the ie in subelement 332 * as copied (by setting eid field to WLAN_EID_SSID, 333 * which is skipped anyway). 334 * For vendor ie, compare OUI + type + subType to 335 * determine if they are the same ie. 336 */ 337 if (tmp_old[0] == WLAN_EID_VENDOR_SPECIFIC) { 338 if (!memcmp(tmp_old + 2, tmp + 2, 5)) { 339 /* same vendor ie, copy from 340 * subelement 341 */ 342 memcpy(pos, tmp, tmp[1] + 2); 343 pos += tmp[1] + 2; 344 tmp[0] = WLAN_EID_SSID; 345 } else { 346 memcpy(pos, tmp_old, tmp_old[1] + 2); 347 pos += tmp_old[1] + 2; 348 } 349 } else { 350 /* copy ie from subelement into new ie */ 351 memcpy(pos, tmp, tmp[1] + 2); 352 pos += tmp[1] + 2; 353 tmp[0] = WLAN_EID_SSID; 354 } 355 } 356 357 if (tmp_old + tmp_old[1] + 2 - ie == ielen) 358 break; 359 360 tmp_old += tmp_old[1] + 2; 361 } 362 363 /* go through subelement again to check if there is any ie not 364 * copied to new ie, skip ssid, capability, bssid-index ie 365 */ 366 tmp_new = sub_copy; 367 while (tmp_new + tmp_new[1] + 2 - sub_copy <= subie_len) { 368 if (!(tmp_new[0] == WLAN_EID_NON_TX_BSSID_CAP || 369 tmp_new[0] == WLAN_EID_SSID)) { 370 memcpy(pos, tmp_new, tmp_new[1] + 2); 371 pos += tmp_new[1] + 2; 372 } 373 if (tmp_new + tmp_new[1] + 2 - sub_copy == subie_len) 374 break; 375 tmp_new += tmp_new[1] + 2; 376 } 377 378 kfree(sub_copy); 379 return pos - new_ie; 380 } 381 382 static bool is_bss(struct cfg80211_bss *a, const u8 *bssid, 383 const u8 *ssid, size_t ssid_len) 384 { 385 const struct cfg80211_bss_ies *ies; 386 const struct element *ssid_elem; 387 388 if (bssid && !ether_addr_equal(a->bssid, bssid)) 389 return false; 390 391 if (!ssid) 392 return true; 393 394 ies = rcu_access_pointer(a->ies); 395 if (!ies) 396 return false; 397 ssid_elem = cfg80211_find_elem(WLAN_EID_SSID, ies->data, ies->len); 398 if (!ssid_elem) 399 return false; 400 if (ssid_elem->datalen != ssid_len) 401 return false; 402 return memcmp(ssid_elem->data, ssid, ssid_len) == 0; 403 } 404 405 static int 406 cfg80211_add_nontrans_list(struct cfg80211_bss *trans_bss, 407 struct cfg80211_bss *nontrans_bss) 408 { 409 const u8 *ssid; 410 size_t ssid_len; 411 struct cfg80211_bss *bss = NULL; 412 413 rcu_read_lock(); 414 ssid = ieee80211_bss_get_ie(nontrans_bss, WLAN_EID_SSID); 415 if (!ssid) { 416 rcu_read_unlock(); 417 return -EINVAL; 418 } 419 ssid_len = ssid[1]; 420 ssid = ssid + 2; 421 422 /* check if nontrans_bss is in the list */ 423 list_for_each_entry(bss, &trans_bss->nontrans_list, nontrans_list) { 424 if (is_bss(bss, nontrans_bss->bssid, ssid, ssid_len)) { 425 rcu_read_unlock(); 426 return 0; 427 } 428 } 429 430 rcu_read_unlock(); 431 432 /* add to the list */ 433 list_add_tail(&nontrans_bss->nontrans_list, &trans_bss->nontrans_list); 434 return 0; 435 } 436 437 static void __cfg80211_bss_expire(struct cfg80211_registered_device *rdev, 438 unsigned long expire_time) 439 { 440 struct cfg80211_internal_bss *bss, *tmp; 441 bool expired = false; 442 443 lockdep_assert_held(&rdev->bss_lock); 444 445 list_for_each_entry_safe(bss, tmp, &rdev->bss_list, list) { 446 if (atomic_read(&bss->hold)) 447 continue; 448 if (!time_after(expire_time, bss->ts)) 449 continue; 450 451 if (__cfg80211_unlink_bss(rdev, bss)) 452 expired = true; 453 } 454 455 if (expired) 456 rdev->bss_generation++; 457 } 458 459 static bool cfg80211_bss_expire_oldest(struct cfg80211_registered_device *rdev) 460 { 461 struct cfg80211_internal_bss *bss, *oldest = NULL; 462 bool ret; 463 464 lockdep_assert_held(&rdev->bss_lock); 465 466 list_for_each_entry(bss, &rdev->bss_list, list) { 467 if (atomic_read(&bss->hold)) 468 continue; 469 470 if (!list_empty(&bss->hidden_list) && 471 !bss->pub.hidden_beacon_bss) 472 continue; 473 474 if (oldest && time_before(oldest->ts, bss->ts)) 475 continue; 476 oldest = bss; 477 } 478 479 if (WARN_ON(!oldest)) 480 return false; 481 482 /* 483 * The callers make sure to increase rdev->bss_generation if anything 484 * gets removed (and a new entry added), so there's no need to also do 485 * it here. 486 */ 487 488 ret = __cfg80211_unlink_bss(rdev, oldest); 489 WARN_ON(!ret); 490 return ret; 491 } 492 493 static u8 cfg80211_parse_bss_param(u8 data, 494 struct cfg80211_colocated_ap *coloc_ap) 495 { 496 coloc_ap->oct_recommended = 497 u8_get_bits(data, IEEE80211_RNR_TBTT_PARAMS_OCT_RECOMMENDED); 498 coloc_ap->same_ssid = 499 u8_get_bits(data, IEEE80211_RNR_TBTT_PARAMS_SAME_SSID); 500 coloc_ap->multi_bss = 501 u8_get_bits(data, IEEE80211_RNR_TBTT_PARAMS_MULTI_BSSID); 502 coloc_ap->transmitted_bssid = 503 u8_get_bits(data, IEEE80211_RNR_TBTT_PARAMS_TRANSMITTED_BSSID); 504 coloc_ap->unsolicited_probe = 505 u8_get_bits(data, IEEE80211_RNR_TBTT_PARAMS_PROBE_ACTIVE); 506 coloc_ap->colocated_ess = 507 u8_get_bits(data, IEEE80211_RNR_TBTT_PARAMS_COLOC_ESS); 508 509 return u8_get_bits(data, IEEE80211_RNR_TBTT_PARAMS_COLOC_AP); 510 } 511 512 static int cfg80211_calc_short_ssid(const struct cfg80211_bss_ies *ies, 513 const struct element **elem, u32 *s_ssid) 514 { 515 516 *elem = cfg80211_find_elem(WLAN_EID_SSID, ies->data, ies->len); 517 if (!*elem || (*elem)->datalen > IEEE80211_MAX_SSID_LEN) 518 return -EINVAL; 519 520 *s_ssid = ~crc32_le(~0, (*elem)->data, (*elem)->datalen); 521 return 0; 522 } 523 524 static void cfg80211_free_coloc_ap_list(struct list_head *coloc_ap_list) 525 { 526 struct cfg80211_colocated_ap *ap, *tmp_ap; 527 528 list_for_each_entry_safe(ap, tmp_ap, coloc_ap_list, list) { 529 list_del(&ap->list); 530 kfree(ap); 531 } 532 } 533 534 static int cfg80211_parse_ap_info(struct cfg80211_colocated_ap *entry, 535 const u8 *pos, u8 length, 536 const struct element *ssid_elem, 537 int s_ssid_tmp) 538 { 539 /* skip the TBTT offset */ 540 pos++; 541 542 memcpy(entry->bssid, pos, ETH_ALEN); 543 pos += ETH_ALEN; 544 545 if (length == IEEE80211_TBTT_INFO_OFFSET_BSSID_SSSID_BSS_PARAM) { 546 memcpy(&entry->short_ssid, pos, 547 sizeof(entry->short_ssid)); 548 entry->short_ssid_valid = true; 549 pos += 4; 550 } 551 552 /* skip non colocated APs */ 553 if (!cfg80211_parse_bss_param(*pos, entry)) 554 return -EINVAL; 555 pos++; 556 557 if (length == IEEE80211_TBTT_INFO_OFFSET_BSSID_BSS_PARAM) { 558 /* 559 * no information about the short ssid. Consider the entry valid 560 * for now. It would later be dropped in case there are explicit 561 * SSIDs that need to be matched 562 */ 563 if (!entry->same_ssid) 564 return 0; 565 } 566 567 if (entry->same_ssid) { 568 entry->short_ssid = s_ssid_tmp; 569 entry->short_ssid_valid = true; 570 571 /* 572 * This is safe because we validate datalen in 573 * cfg80211_parse_colocated_ap(), before calling this 574 * function. 575 */ 576 memcpy(&entry->ssid, &ssid_elem->data, 577 ssid_elem->datalen); 578 entry->ssid_len = ssid_elem->datalen; 579 } 580 return 0; 581 } 582 583 static int cfg80211_parse_colocated_ap(const struct cfg80211_bss_ies *ies, 584 struct list_head *list) 585 { 586 struct ieee80211_neighbor_ap_info *ap_info; 587 const struct element *elem, *ssid_elem; 588 const u8 *pos, *end; 589 u32 s_ssid_tmp; 590 int n_coloc = 0, ret; 591 LIST_HEAD(ap_list); 592 593 elem = cfg80211_find_elem(WLAN_EID_REDUCED_NEIGHBOR_REPORT, ies->data, 594 ies->len); 595 if (!elem) 596 return 0; 597 598 pos = elem->data; 599 end = pos + elem->datalen; 600 601 ret = cfg80211_calc_short_ssid(ies, &ssid_elem, &s_ssid_tmp); 602 if (ret) 603 return ret; 604 605 /* RNR IE may contain more than one NEIGHBOR_AP_INFO */ 606 while (pos + sizeof(*ap_info) <= end) { 607 enum nl80211_band band; 608 int freq; 609 u8 length, i, count; 610 611 ap_info = (void *)pos; 612 count = u8_get_bits(ap_info->tbtt_info_hdr, 613 IEEE80211_AP_INFO_TBTT_HDR_COUNT) + 1; 614 length = ap_info->tbtt_info_len; 615 616 pos += sizeof(*ap_info); 617 618 if (!ieee80211_operating_class_to_band(ap_info->op_class, 619 &band)) 620 break; 621 622 freq = ieee80211_channel_to_frequency(ap_info->channel, band); 623 624 if (end - pos < count * length) 625 break; 626 627 /* 628 * TBTT info must include bss param + BSSID + 629 * (short SSID or same_ssid bit to be set). 630 * ignore other options, and move to the 631 * next AP info 632 */ 633 if (band != NL80211_BAND_6GHZ || 634 (length != IEEE80211_TBTT_INFO_OFFSET_BSSID_BSS_PARAM && 635 length < IEEE80211_TBTT_INFO_OFFSET_BSSID_SSSID_BSS_PARAM)) { 636 pos += count * length; 637 continue; 638 } 639 640 for (i = 0; i < count; i++) { 641 struct cfg80211_colocated_ap *entry; 642 643 entry = kzalloc(sizeof(*entry) + IEEE80211_MAX_SSID_LEN, 644 GFP_ATOMIC); 645 646 if (!entry) 647 break; 648 649 entry->center_freq = freq; 650 651 if (!cfg80211_parse_ap_info(entry, pos, length, 652 ssid_elem, s_ssid_tmp)) { 653 n_coloc++; 654 list_add_tail(&entry->list, &ap_list); 655 } else { 656 kfree(entry); 657 } 658 659 pos += length; 660 } 661 } 662 663 if (pos != end) { 664 cfg80211_free_coloc_ap_list(&ap_list); 665 return 0; 666 } 667 668 list_splice_tail(&ap_list, list); 669 return n_coloc; 670 } 671 672 static void cfg80211_scan_req_add_chan(struct cfg80211_scan_request *request, 673 struct ieee80211_channel *chan, 674 bool add_to_6ghz) 675 { 676 int i; 677 u32 n_channels = request->n_channels; 678 struct cfg80211_scan_6ghz_params *params = 679 &request->scan_6ghz_params[request->n_6ghz_params]; 680 681 for (i = 0; i < n_channels; i++) { 682 if (request->channels[i] == chan) { 683 if (add_to_6ghz) 684 params->channel_idx = i; 685 return; 686 } 687 } 688 689 request->channels[n_channels] = chan; 690 if (add_to_6ghz) 691 request->scan_6ghz_params[request->n_6ghz_params].channel_idx = 692 n_channels; 693 694 request->n_channels++; 695 } 696 697 static bool cfg80211_find_ssid_match(struct cfg80211_colocated_ap *ap, 698 struct cfg80211_scan_request *request) 699 { 700 int i; 701 u32 s_ssid; 702 703 for (i = 0; i < request->n_ssids; i++) { 704 /* wildcard ssid in the scan request */ 705 if (!request->ssids[i].ssid_len) 706 return true; 707 708 if (ap->ssid_len && 709 ap->ssid_len == request->ssids[i].ssid_len) { 710 if (!memcmp(request->ssids[i].ssid, ap->ssid, 711 ap->ssid_len)) 712 return true; 713 } else if (ap->short_ssid_valid) { 714 s_ssid = ~crc32_le(~0, request->ssids[i].ssid, 715 request->ssids[i].ssid_len); 716 717 if (ap->short_ssid == s_ssid) 718 return true; 719 } 720 } 721 722 return false; 723 } 724 725 static int cfg80211_scan_6ghz(struct cfg80211_registered_device *rdev) 726 { 727 u8 i; 728 struct cfg80211_colocated_ap *ap; 729 int n_channels, count = 0, err; 730 struct cfg80211_scan_request *request, *rdev_req = rdev->scan_req; 731 LIST_HEAD(coloc_ap_list); 732 bool need_scan_psc = true; 733 const struct ieee80211_sband_iftype_data *iftd; 734 735 rdev_req->scan_6ghz = true; 736 737 if (!rdev->wiphy.bands[NL80211_BAND_6GHZ]) 738 return -EOPNOTSUPP; 739 740 iftd = ieee80211_get_sband_iftype_data(rdev->wiphy.bands[NL80211_BAND_6GHZ], 741 rdev_req->wdev->iftype); 742 if (!iftd || !iftd->he_cap.has_he) 743 return -EOPNOTSUPP; 744 745 n_channels = rdev->wiphy.bands[NL80211_BAND_6GHZ]->n_channels; 746 747 if (rdev_req->flags & NL80211_SCAN_FLAG_COLOCATED_6GHZ) { 748 struct cfg80211_internal_bss *intbss; 749 750 spin_lock_bh(&rdev->bss_lock); 751 list_for_each_entry(intbss, &rdev->bss_list, list) { 752 struct cfg80211_bss *res = &intbss->pub; 753 const struct cfg80211_bss_ies *ies; 754 755 ies = rcu_access_pointer(res->ies); 756 count += cfg80211_parse_colocated_ap(ies, 757 &coloc_ap_list); 758 } 759 spin_unlock_bh(&rdev->bss_lock); 760 } 761 762 request = kzalloc(struct_size(request, channels, n_channels) + 763 sizeof(*request->scan_6ghz_params) * count + 764 sizeof(*request->ssids) * rdev_req->n_ssids, 765 GFP_KERNEL); 766 if (!request) { 767 cfg80211_free_coloc_ap_list(&coloc_ap_list); 768 return -ENOMEM; 769 } 770 771 *request = *rdev_req; 772 request->n_channels = 0; 773 request->scan_6ghz_params = 774 (void *)&request->channels[n_channels]; 775 776 /* 777 * PSC channels should not be scanned in case of direct scan with 1 SSID 778 * and at least one of the reported co-located APs with same SSID 779 * indicating that all APs in the same ESS are co-located 780 */ 781 if (count && request->n_ssids == 1 && request->ssids[0].ssid_len) { 782 list_for_each_entry(ap, &coloc_ap_list, list) { 783 if (ap->colocated_ess && 784 cfg80211_find_ssid_match(ap, request)) { 785 need_scan_psc = false; 786 break; 787 } 788 } 789 } 790 791 /* 792 * add to the scan request the channels that need to be scanned 793 * regardless of the collocated APs (PSC channels or all channels 794 * in case that NL80211_SCAN_FLAG_COLOCATED_6GHZ is not set) 795 */ 796 for (i = 0; i < rdev_req->n_channels; i++) { 797 if (rdev_req->channels[i]->band == NL80211_BAND_6GHZ && 798 ((need_scan_psc && 799 cfg80211_channel_is_psc(rdev_req->channels[i])) || 800 !(rdev_req->flags & NL80211_SCAN_FLAG_COLOCATED_6GHZ))) { 801 cfg80211_scan_req_add_chan(request, 802 rdev_req->channels[i], 803 false); 804 } 805 } 806 807 if (!(rdev_req->flags & NL80211_SCAN_FLAG_COLOCATED_6GHZ)) 808 goto skip; 809 810 list_for_each_entry(ap, &coloc_ap_list, list) { 811 bool found = false; 812 struct cfg80211_scan_6ghz_params *scan_6ghz_params = 813 &request->scan_6ghz_params[request->n_6ghz_params]; 814 struct ieee80211_channel *chan = 815 ieee80211_get_channel(&rdev->wiphy, ap->center_freq); 816 817 if (!chan || chan->flags & IEEE80211_CHAN_DISABLED) 818 continue; 819 820 for (i = 0; i < rdev_req->n_channels; i++) { 821 if (rdev_req->channels[i] == chan) 822 found = true; 823 } 824 825 if (!found) 826 continue; 827 828 if (request->n_ssids > 0 && 829 !cfg80211_find_ssid_match(ap, request)) 830 continue; 831 832 cfg80211_scan_req_add_chan(request, chan, true); 833 memcpy(scan_6ghz_params->bssid, ap->bssid, ETH_ALEN); 834 scan_6ghz_params->short_ssid = ap->short_ssid; 835 scan_6ghz_params->short_ssid_valid = ap->short_ssid_valid; 836 scan_6ghz_params->unsolicited_probe = ap->unsolicited_probe; 837 838 /* 839 * If a PSC channel is added to the scan and 'need_scan_psc' is 840 * set to false, then all the APs that the scan logic is 841 * interested with on the channel are collocated and thus there 842 * is no need to perform the initial PSC channel listen. 843 */ 844 if (cfg80211_channel_is_psc(chan) && !need_scan_psc) 845 scan_6ghz_params->psc_no_listen = true; 846 847 request->n_6ghz_params++; 848 } 849 850 skip: 851 cfg80211_free_coloc_ap_list(&coloc_ap_list); 852 853 if (request->n_channels) { 854 struct cfg80211_scan_request *old = rdev->int_scan_req; 855 rdev->int_scan_req = request; 856 857 /* 858 * Add the ssids from the parent scan request to the new scan 859 * request, so the driver would be able to use them in its 860 * probe requests to discover hidden APs on PSC channels. 861 */ 862 request->ssids = (void *)&request->channels[request->n_channels]; 863 request->n_ssids = rdev_req->n_ssids; 864 memcpy(request->ssids, rdev_req->ssids, sizeof(*request->ssids) * 865 request->n_ssids); 866 867 /* 868 * If this scan follows a previous scan, save the scan start 869 * info from the first part of the scan 870 */ 871 if (old) 872 rdev->int_scan_req->info = old->info; 873 874 err = rdev_scan(rdev, request); 875 if (err) { 876 rdev->int_scan_req = old; 877 kfree(request); 878 } else { 879 kfree(old); 880 } 881 882 return err; 883 } 884 885 kfree(request); 886 return -EINVAL; 887 } 888 889 int cfg80211_scan(struct cfg80211_registered_device *rdev) 890 { 891 struct cfg80211_scan_request *request; 892 struct cfg80211_scan_request *rdev_req = rdev->scan_req; 893 u32 n_channels = 0, idx, i; 894 895 if (!(rdev->wiphy.flags & WIPHY_FLAG_SPLIT_SCAN_6GHZ)) 896 return rdev_scan(rdev, rdev_req); 897 898 for (i = 0; i < rdev_req->n_channels; i++) { 899 if (rdev_req->channels[i]->band != NL80211_BAND_6GHZ) 900 n_channels++; 901 } 902 903 if (!n_channels) 904 return cfg80211_scan_6ghz(rdev); 905 906 request = kzalloc(struct_size(request, channels, n_channels), 907 GFP_KERNEL); 908 if (!request) 909 return -ENOMEM; 910 911 *request = *rdev_req; 912 request->n_channels = n_channels; 913 914 for (i = idx = 0; i < rdev_req->n_channels; i++) { 915 if (rdev_req->channels[i]->band != NL80211_BAND_6GHZ) 916 request->channels[idx++] = rdev_req->channels[i]; 917 } 918 919 rdev_req->scan_6ghz = false; 920 rdev->int_scan_req = request; 921 return rdev_scan(rdev, request); 922 } 923 924 void ___cfg80211_scan_done(struct cfg80211_registered_device *rdev, 925 bool send_message) 926 { 927 struct cfg80211_scan_request *request, *rdev_req; 928 struct wireless_dev *wdev; 929 struct sk_buff *msg; 930 #ifdef CONFIG_CFG80211_WEXT 931 union iwreq_data wrqu; 932 #endif 933 934 lockdep_assert_held(&rdev->wiphy.mtx); 935 936 if (rdev->scan_msg) { 937 nl80211_send_scan_msg(rdev, rdev->scan_msg); 938 rdev->scan_msg = NULL; 939 return; 940 } 941 942 rdev_req = rdev->scan_req; 943 if (!rdev_req) 944 return; 945 946 wdev = rdev_req->wdev; 947 request = rdev->int_scan_req ? rdev->int_scan_req : rdev_req; 948 949 if (wdev_running(wdev) && 950 (rdev->wiphy.flags & WIPHY_FLAG_SPLIT_SCAN_6GHZ) && 951 !rdev_req->scan_6ghz && !request->info.aborted && 952 !cfg80211_scan_6ghz(rdev)) 953 return; 954 955 /* 956 * This must be before sending the other events! 957 * Otherwise, wpa_supplicant gets completely confused with 958 * wext events. 959 */ 960 if (wdev->netdev) 961 cfg80211_sme_scan_done(wdev->netdev); 962 963 if (!request->info.aborted && 964 request->flags & NL80211_SCAN_FLAG_FLUSH) { 965 /* flush entries from previous scans */ 966 spin_lock_bh(&rdev->bss_lock); 967 __cfg80211_bss_expire(rdev, request->scan_start); 968 spin_unlock_bh(&rdev->bss_lock); 969 } 970 971 msg = nl80211_build_scan_msg(rdev, wdev, request->info.aborted); 972 973 #ifdef CONFIG_CFG80211_WEXT 974 if (wdev->netdev && !request->info.aborted) { 975 memset(&wrqu, 0, sizeof(wrqu)); 976 977 wireless_send_event(wdev->netdev, SIOCGIWSCAN, &wrqu, NULL); 978 } 979 #endif 980 981 dev_put(wdev->netdev); 982 983 kfree(rdev->int_scan_req); 984 rdev->int_scan_req = NULL; 985 986 kfree(rdev->scan_req); 987 rdev->scan_req = NULL; 988 989 if (!send_message) 990 rdev->scan_msg = msg; 991 else 992 nl80211_send_scan_msg(rdev, msg); 993 } 994 995 void __cfg80211_scan_done(struct work_struct *wk) 996 { 997 struct cfg80211_registered_device *rdev; 998 999 rdev = container_of(wk, struct cfg80211_registered_device, 1000 scan_done_wk); 1001 1002 wiphy_lock(&rdev->wiphy); 1003 ___cfg80211_scan_done(rdev, true); 1004 wiphy_unlock(&rdev->wiphy); 1005 } 1006 1007 void cfg80211_scan_done(struct cfg80211_scan_request *request, 1008 struct cfg80211_scan_info *info) 1009 { 1010 struct cfg80211_scan_info old_info = request->info; 1011 1012 trace_cfg80211_scan_done(request, info); 1013 WARN_ON(request != wiphy_to_rdev(request->wiphy)->scan_req && 1014 request != wiphy_to_rdev(request->wiphy)->int_scan_req); 1015 1016 request->info = *info; 1017 1018 /* 1019 * In case the scan is split, the scan_start_tsf and tsf_bssid should 1020 * be of the first part. In such a case old_info.scan_start_tsf should 1021 * be non zero. 1022 */ 1023 if (request->scan_6ghz && old_info.scan_start_tsf) { 1024 request->info.scan_start_tsf = old_info.scan_start_tsf; 1025 memcpy(request->info.tsf_bssid, old_info.tsf_bssid, 1026 sizeof(request->info.tsf_bssid)); 1027 } 1028 1029 request->notified = true; 1030 queue_work(cfg80211_wq, &wiphy_to_rdev(request->wiphy)->scan_done_wk); 1031 } 1032 EXPORT_SYMBOL(cfg80211_scan_done); 1033 1034 void cfg80211_add_sched_scan_req(struct cfg80211_registered_device *rdev, 1035 struct cfg80211_sched_scan_request *req) 1036 { 1037 lockdep_assert_held(&rdev->wiphy.mtx); 1038 1039 list_add_rcu(&req->list, &rdev->sched_scan_req_list); 1040 } 1041 1042 static void cfg80211_del_sched_scan_req(struct cfg80211_registered_device *rdev, 1043 struct cfg80211_sched_scan_request *req) 1044 { 1045 lockdep_assert_held(&rdev->wiphy.mtx); 1046 1047 list_del_rcu(&req->list); 1048 kfree_rcu(req, rcu_head); 1049 } 1050 1051 static struct cfg80211_sched_scan_request * 1052 cfg80211_find_sched_scan_req(struct cfg80211_registered_device *rdev, u64 reqid) 1053 { 1054 struct cfg80211_sched_scan_request *pos; 1055 1056 list_for_each_entry_rcu(pos, &rdev->sched_scan_req_list, list, 1057 lockdep_is_held(&rdev->wiphy.mtx)) { 1058 if (pos->reqid == reqid) 1059 return pos; 1060 } 1061 return NULL; 1062 } 1063 1064 /* 1065 * Determines if a scheduled scan request can be handled. When a legacy 1066 * scheduled scan is running no other scheduled scan is allowed regardless 1067 * whether the request is for legacy or multi-support scan. When a multi-support 1068 * scheduled scan is running a request for legacy scan is not allowed. In this 1069 * case a request for multi-support scan can be handled if resources are 1070 * available, ie. struct wiphy::max_sched_scan_reqs limit is not yet reached. 1071 */ 1072 int cfg80211_sched_scan_req_possible(struct cfg80211_registered_device *rdev, 1073 bool want_multi) 1074 { 1075 struct cfg80211_sched_scan_request *pos; 1076 int i = 0; 1077 1078 list_for_each_entry(pos, &rdev->sched_scan_req_list, list) { 1079 /* request id zero means legacy in progress */ 1080 if (!i && !pos->reqid) 1081 return -EINPROGRESS; 1082 i++; 1083 } 1084 1085 if (i) { 1086 /* no legacy allowed when multi request(s) are active */ 1087 if (!want_multi) 1088 return -EINPROGRESS; 1089 1090 /* resource limit reached */ 1091 if (i == rdev->wiphy.max_sched_scan_reqs) 1092 return -ENOSPC; 1093 } 1094 return 0; 1095 } 1096 1097 void cfg80211_sched_scan_results_wk(struct work_struct *work) 1098 { 1099 struct cfg80211_registered_device *rdev; 1100 struct cfg80211_sched_scan_request *req, *tmp; 1101 1102 rdev = container_of(work, struct cfg80211_registered_device, 1103 sched_scan_res_wk); 1104 1105 wiphy_lock(&rdev->wiphy); 1106 list_for_each_entry_safe(req, tmp, &rdev->sched_scan_req_list, list) { 1107 if (req->report_results) { 1108 req->report_results = false; 1109 if (req->flags & NL80211_SCAN_FLAG_FLUSH) { 1110 /* flush entries from previous scans */ 1111 spin_lock_bh(&rdev->bss_lock); 1112 __cfg80211_bss_expire(rdev, req->scan_start); 1113 spin_unlock_bh(&rdev->bss_lock); 1114 req->scan_start = jiffies; 1115 } 1116 nl80211_send_sched_scan(req, 1117 NL80211_CMD_SCHED_SCAN_RESULTS); 1118 } 1119 } 1120 wiphy_unlock(&rdev->wiphy); 1121 } 1122 1123 void cfg80211_sched_scan_results(struct wiphy *wiphy, u64 reqid) 1124 { 1125 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy); 1126 struct cfg80211_sched_scan_request *request; 1127 1128 trace_cfg80211_sched_scan_results(wiphy, reqid); 1129 /* ignore if we're not scanning */ 1130 1131 rcu_read_lock(); 1132 request = cfg80211_find_sched_scan_req(rdev, reqid); 1133 if (request) { 1134 request->report_results = true; 1135 queue_work(cfg80211_wq, &rdev->sched_scan_res_wk); 1136 } 1137 rcu_read_unlock(); 1138 } 1139 EXPORT_SYMBOL(cfg80211_sched_scan_results); 1140 1141 void cfg80211_sched_scan_stopped_locked(struct wiphy *wiphy, u64 reqid) 1142 { 1143 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy); 1144 1145 lockdep_assert_held(&wiphy->mtx); 1146 1147 trace_cfg80211_sched_scan_stopped(wiphy, reqid); 1148 1149 __cfg80211_stop_sched_scan(rdev, reqid, true); 1150 } 1151 EXPORT_SYMBOL(cfg80211_sched_scan_stopped_locked); 1152 1153 void cfg80211_sched_scan_stopped(struct wiphy *wiphy, u64 reqid) 1154 { 1155 wiphy_lock(wiphy); 1156 cfg80211_sched_scan_stopped_locked(wiphy, reqid); 1157 wiphy_unlock(wiphy); 1158 } 1159 EXPORT_SYMBOL(cfg80211_sched_scan_stopped); 1160 1161 int cfg80211_stop_sched_scan_req(struct cfg80211_registered_device *rdev, 1162 struct cfg80211_sched_scan_request *req, 1163 bool driver_initiated) 1164 { 1165 lockdep_assert_held(&rdev->wiphy.mtx); 1166 1167 if (!driver_initiated) { 1168 int err = rdev_sched_scan_stop(rdev, req->dev, req->reqid); 1169 if (err) 1170 return err; 1171 } 1172 1173 nl80211_send_sched_scan(req, NL80211_CMD_SCHED_SCAN_STOPPED); 1174 1175 cfg80211_del_sched_scan_req(rdev, req); 1176 1177 return 0; 1178 } 1179 1180 int __cfg80211_stop_sched_scan(struct cfg80211_registered_device *rdev, 1181 u64 reqid, bool driver_initiated) 1182 { 1183 struct cfg80211_sched_scan_request *sched_scan_req; 1184 1185 lockdep_assert_held(&rdev->wiphy.mtx); 1186 1187 sched_scan_req = cfg80211_find_sched_scan_req(rdev, reqid); 1188 if (!sched_scan_req) 1189 return -ENOENT; 1190 1191 return cfg80211_stop_sched_scan_req(rdev, sched_scan_req, 1192 driver_initiated); 1193 } 1194 1195 void cfg80211_bss_age(struct cfg80211_registered_device *rdev, 1196 unsigned long age_secs) 1197 { 1198 struct cfg80211_internal_bss *bss; 1199 unsigned long age_jiffies = msecs_to_jiffies(age_secs * MSEC_PER_SEC); 1200 1201 spin_lock_bh(&rdev->bss_lock); 1202 list_for_each_entry(bss, &rdev->bss_list, list) 1203 bss->ts -= age_jiffies; 1204 spin_unlock_bh(&rdev->bss_lock); 1205 } 1206 1207 void cfg80211_bss_expire(struct cfg80211_registered_device *rdev) 1208 { 1209 __cfg80211_bss_expire(rdev, jiffies - IEEE80211_SCAN_RESULT_EXPIRE); 1210 } 1211 1212 void cfg80211_bss_flush(struct wiphy *wiphy) 1213 { 1214 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy); 1215 1216 spin_lock_bh(&rdev->bss_lock); 1217 __cfg80211_bss_expire(rdev, jiffies); 1218 spin_unlock_bh(&rdev->bss_lock); 1219 } 1220 EXPORT_SYMBOL(cfg80211_bss_flush); 1221 1222 const struct element * 1223 cfg80211_find_elem_match(u8 eid, const u8 *ies, unsigned int len, 1224 const u8 *match, unsigned int match_len, 1225 unsigned int match_offset) 1226 { 1227 const struct element *elem; 1228 1229 for_each_element_id(elem, eid, ies, len) { 1230 if (elem->datalen >= match_offset + match_len && 1231 !memcmp(elem->data + match_offset, match, match_len)) 1232 return elem; 1233 } 1234 1235 return NULL; 1236 } 1237 EXPORT_SYMBOL(cfg80211_find_elem_match); 1238 1239 const struct element *cfg80211_find_vendor_elem(unsigned int oui, int oui_type, 1240 const u8 *ies, 1241 unsigned int len) 1242 { 1243 const struct element *elem; 1244 u8 match[] = { oui >> 16, oui >> 8, oui, oui_type }; 1245 int match_len = (oui_type < 0) ? 3 : sizeof(match); 1246 1247 if (WARN_ON(oui_type > 0xff)) 1248 return NULL; 1249 1250 elem = cfg80211_find_elem_match(WLAN_EID_VENDOR_SPECIFIC, ies, len, 1251 match, match_len, 0); 1252 1253 if (!elem || elem->datalen < 4) 1254 return NULL; 1255 1256 return elem; 1257 } 1258 EXPORT_SYMBOL(cfg80211_find_vendor_elem); 1259 1260 /** 1261 * enum bss_compare_mode - BSS compare mode 1262 * @BSS_CMP_REGULAR: regular compare mode (for insertion and normal find) 1263 * @BSS_CMP_HIDE_ZLEN: find hidden SSID with zero-length mode 1264 * @BSS_CMP_HIDE_NUL: find hidden SSID with NUL-ed out mode 1265 */ 1266 enum bss_compare_mode { 1267 BSS_CMP_REGULAR, 1268 BSS_CMP_HIDE_ZLEN, 1269 BSS_CMP_HIDE_NUL, 1270 }; 1271 1272 static int cmp_bss(struct cfg80211_bss *a, 1273 struct cfg80211_bss *b, 1274 enum bss_compare_mode mode) 1275 { 1276 const struct cfg80211_bss_ies *a_ies, *b_ies; 1277 const u8 *ie1 = NULL; 1278 const u8 *ie2 = NULL; 1279 int i, r; 1280 1281 if (a->channel != b->channel) 1282 return b->channel->center_freq - a->channel->center_freq; 1283 1284 a_ies = rcu_access_pointer(a->ies); 1285 if (!a_ies) 1286 return -1; 1287 b_ies = rcu_access_pointer(b->ies); 1288 if (!b_ies) 1289 return 1; 1290 1291 if (WLAN_CAPABILITY_IS_STA_BSS(a->capability)) 1292 ie1 = cfg80211_find_ie(WLAN_EID_MESH_ID, 1293 a_ies->data, a_ies->len); 1294 if (WLAN_CAPABILITY_IS_STA_BSS(b->capability)) 1295 ie2 = cfg80211_find_ie(WLAN_EID_MESH_ID, 1296 b_ies->data, b_ies->len); 1297 if (ie1 && ie2) { 1298 int mesh_id_cmp; 1299 1300 if (ie1[1] == ie2[1]) 1301 mesh_id_cmp = memcmp(ie1 + 2, ie2 + 2, ie1[1]); 1302 else 1303 mesh_id_cmp = ie2[1] - ie1[1]; 1304 1305 ie1 = cfg80211_find_ie(WLAN_EID_MESH_CONFIG, 1306 a_ies->data, a_ies->len); 1307 ie2 = cfg80211_find_ie(WLAN_EID_MESH_CONFIG, 1308 b_ies->data, b_ies->len); 1309 if (ie1 && ie2) { 1310 if (mesh_id_cmp) 1311 return mesh_id_cmp; 1312 if (ie1[1] != ie2[1]) 1313 return ie2[1] - ie1[1]; 1314 return memcmp(ie1 + 2, ie2 + 2, ie1[1]); 1315 } 1316 } 1317 1318 r = memcmp(a->bssid, b->bssid, sizeof(a->bssid)); 1319 if (r) 1320 return r; 1321 1322 ie1 = cfg80211_find_ie(WLAN_EID_SSID, a_ies->data, a_ies->len); 1323 ie2 = cfg80211_find_ie(WLAN_EID_SSID, b_ies->data, b_ies->len); 1324 1325 if (!ie1 && !ie2) 1326 return 0; 1327 1328 /* 1329 * Note that with "hide_ssid", the function returns a match if 1330 * the already-present BSS ("b") is a hidden SSID beacon for 1331 * the new BSS ("a"). 1332 */ 1333 1334 /* sort missing IE before (left of) present IE */ 1335 if (!ie1) 1336 return -1; 1337 if (!ie2) 1338 return 1; 1339 1340 switch (mode) { 1341 case BSS_CMP_HIDE_ZLEN: 1342 /* 1343 * In ZLEN mode we assume the BSS entry we're 1344 * looking for has a zero-length SSID. So if 1345 * the one we're looking at right now has that, 1346 * return 0. Otherwise, return the difference 1347 * in length, but since we're looking for the 1348 * 0-length it's really equivalent to returning 1349 * the length of the one we're looking at. 1350 * 1351 * No content comparison is needed as we assume 1352 * the content length is zero. 1353 */ 1354 return ie2[1]; 1355 case BSS_CMP_REGULAR: 1356 default: 1357 /* sort by length first, then by contents */ 1358 if (ie1[1] != ie2[1]) 1359 return ie2[1] - ie1[1]; 1360 return memcmp(ie1 + 2, ie2 + 2, ie1[1]); 1361 case BSS_CMP_HIDE_NUL: 1362 if (ie1[1] != ie2[1]) 1363 return ie2[1] - ie1[1]; 1364 /* this is equivalent to memcmp(zeroes, ie2 + 2, len) */ 1365 for (i = 0; i < ie2[1]; i++) 1366 if (ie2[i + 2]) 1367 return -1; 1368 return 0; 1369 } 1370 } 1371 1372 static bool cfg80211_bss_type_match(u16 capability, 1373 enum nl80211_band band, 1374 enum ieee80211_bss_type bss_type) 1375 { 1376 bool ret = true; 1377 u16 mask, val; 1378 1379 if (bss_type == IEEE80211_BSS_TYPE_ANY) 1380 return ret; 1381 1382 if (band == NL80211_BAND_60GHZ) { 1383 mask = WLAN_CAPABILITY_DMG_TYPE_MASK; 1384 switch (bss_type) { 1385 case IEEE80211_BSS_TYPE_ESS: 1386 val = WLAN_CAPABILITY_DMG_TYPE_AP; 1387 break; 1388 case IEEE80211_BSS_TYPE_PBSS: 1389 val = WLAN_CAPABILITY_DMG_TYPE_PBSS; 1390 break; 1391 case IEEE80211_BSS_TYPE_IBSS: 1392 val = WLAN_CAPABILITY_DMG_TYPE_IBSS; 1393 break; 1394 default: 1395 return false; 1396 } 1397 } else { 1398 mask = WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS; 1399 switch (bss_type) { 1400 case IEEE80211_BSS_TYPE_ESS: 1401 val = WLAN_CAPABILITY_ESS; 1402 break; 1403 case IEEE80211_BSS_TYPE_IBSS: 1404 val = WLAN_CAPABILITY_IBSS; 1405 break; 1406 case IEEE80211_BSS_TYPE_MBSS: 1407 val = 0; 1408 break; 1409 default: 1410 return false; 1411 } 1412 } 1413 1414 ret = ((capability & mask) == val); 1415 return ret; 1416 } 1417 1418 /* Returned bss is reference counted and must be cleaned up appropriately. */ 1419 struct cfg80211_bss *cfg80211_get_bss(struct wiphy *wiphy, 1420 struct ieee80211_channel *channel, 1421 const u8 *bssid, 1422 const u8 *ssid, size_t ssid_len, 1423 enum ieee80211_bss_type bss_type, 1424 enum ieee80211_privacy privacy) 1425 { 1426 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy); 1427 struct cfg80211_internal_bss *bss, *res = NULL; 1428 unsigned long now = jiffies; 1429 int bss_privacy; 1430 1431 trace_cfg80211_get_bss(wiphy, channel, bssid, ssid, ssid_len, bss_type, 1432 privacy); 1433 1434 spin_lock_bh(&rdev->bss_lock); 1435 1436 list_for_each_entry(bss, &rdev->bss_list, list) { 1437 if (!cfg80211_bss_type_match(bss->pub.capability, 1438 bss->pub.channel->band, bss_type)) 1439 continue; 1440 1441 bss_privacy = (bss->pub.capability & WLAN_CAPABILITY_PRIVACY); 1442 if ((privacy == IEEE80211_PRIVACY_ON && !bss_privacy) || 1443 (privacy == IEEE80211_PRIVACY_OFF && bss_privacy)) 1444 continue; 1445 if (channel && bss->pub.channel != channel) 1446 continue; 1447 if (!is_valid_ether_addr(bss->pub.bssid)) 1448 continue; 1449 /* Don't get expired BSS structs */ 1450 if (time_after(now, bss->ts + IEEE80211_SCAN_RESULT_EXPIRE) && 1451 !atomic_read(&bss->hold)) 1452 continue; 1453 if (is_bss(&bss->pub, bssid, ssid, ssid_len)) { 1454 res = bss; 1455 bss_ref_get(rdev, res); 1456 break; 1457 } 1458 } 1459 1460 spin_unlock_bh(&rdev->bss_lock); 1461 if (!res) 1462 return NULL; 1463 trace_cfg80211_return_bss(&res->pub); 1464 return &res->pub; 1465 } 1466 EXPORT_SYMBOL(cfg80211_get_bss); 1467 1468 static void rb_insert_bss(struct cfg80211_registered_device *rdev, 1469 struct cfg80211_internal_bss *bss) 1470 { 1471 struct rb_node **p = &rdev->bss_tree.rb_node; 1472 struct rb_node *parent = NULL; 1473 struct cfg80211_internal_bss *tbss; 1474 int cmp; 1475 1476 while (*p) { 1477 parent = *p; 1478 tbss = rb_entry(parent, struct cfg80211_internal_bss, rbn); 1479 1480 cmp = cmp_bss(&bss->pub, &tbss->pub, BSS_CMP_REGULAR); 1481 1482 if (WARN_ON(!cmp)) { 1483 /* will sort of leak this BSS */ 1484 return; 1485 } 1486 1487 if (cmp < 0) 1488 p = &(*p)->rb_left; 1489 else 1490 p = &(*p)->rb_right; 1491 } 1492 1493 rb_link_node(&bss->rbn, parent, p); 1494 rb_insert_color(&bss->rbn, &rdev->bss_tree); 1495 } 1496 1497 static struct cfg80211_internal_bss * 1498 rb_find_bss(struct cfg80211_registered_device *rdev, 1499 struct cfg80211_internal_bss *res, 1500 enum bss_compare_mode mode) 1501 { 1502 struct rb_node *n = rdev->bss_tree.rb_node; 1503 struct cfg80211_internal_bss *bss; 1504 int r; 1505 1506 while (n) { 1507 bss = rb_entry(n, struct cfg80211_internal_bss, rbn); 1508 r = cmp_bss(&res->pub, &bss->pub, mode); 1509 1510 if (r == 0) 1511 return bss; 1512 else if (r < 0) 1513 n = n->rb_left; 1514 else 1515 n = n->rb_right; 1516 } 1517 1518 return NULL; 1519 } 1520 1521 static bool cfg80211_combine_bsses(struct cfg80211_registered_device *rdev, 1522 struct cfg80211_internal_bss *new) 1523 { 1524 const struct cfg80211_bss_ies *ies; 1525 struct cfg80211_internal_bss *bss; 1526 const u8 *ie; 1527 int i, ssidlen; 1528 u8 fold = 0; 1529 u32 n_entries = 0; 1530 1531 ies = rcu_access_pointer(new->pub.beacon_ies); 1532 if (WARN_ON(!ies)) 1533 return false; 1534 1535 ie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len); 1536 if (!ie) { 1537 /* nothing to do */ 1538 return true; 1539 } 1540 1541 ssidlen = ie[1]; 1542 for (i = 0; i < ssidlen; i++) 1543 fold |= ie[2 + i]; 1544 1545 if (fold) { 1546 /* not a hidden SSID */ 1547 return true; 1548 } 1549 1550 /* This is the bad part ... */ 1551 1552 list_for_each_entry(bss, &rdev->bss_list, list) { 1553 /* 1554 * we're iterating all the entries anyway, so take the 1555 * opportunity to validate the list length accounting 1556 */ 1557 n_entries++; 1558 1559 if (!ether_addr_equal(bss->pub.bssid, new->pub.bssid)) 1560 continue; 1561 if (bss->pub.channel != new->pub.channel) 1562 continue; 1563 if (bss->pub.scan_width != new->pub.scan_width) 1564 continue; 1565 if (rcu_access_pointer(bss->pub.beacon_ies)) 1566 continue; 1567 ies = rcu_access_pointer(bss->pub.ies); 1568 if (!ies) 1569 continue; 1570 ie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len); 1571 if (!ie) 1572 continue; 1573 if (ssidlen && ie[1] != ssidlen) 1574 continue; 1575 if (WARN_ON_ONCE(bss->pub.hidden_beacon_bss)) 1576 continue; 1577 if (WARN_ON_ONCE(!list_empty(&bss->hidden_list))) 1578 list_del(&bss->hidden_list); 1579 /* combine them */ 1580 list_add(&bss->hidden_list, &new->hidden_list); 1581 bss->pub.hidden_beacon_bss = &new->pub; 1582 new->refcount += bss->refcount; 1583 rcu_assign_pointer(bss->pub.beacon_ies, 1584 new->pub.beacon_ies); 1585 } 1586 1587 WARN_ONCE(n_entries != rdev->bss_entries, 1588 "rdev bss entries[%d]/list[len:%d] corruption\n", 1589 rdev->bss_entries, n_entries); 1590 1591 return true; 1592 } 1593 1594 struct cfg80211_non_tx_bss { 1595 struct cfg80211_bss *tx_bss; 1596 u8 max_bssid_indicator; 1597 u8 bssid_index; 1598 }; 1599 1600 static bool 1601 cfg80211_update_known_bss(struct cfg80211_registered_device *rdev, 1602 struct cfg80211_internal_bss *known, 1603 struct cfg80211_internal_bss *new, 1604 bool signal_valid) 1605 { 1606 lockdep_assert_held(&rdev->bss_lock); 1607 1608 /* Update IEs */ 1609 if (rcu_access_pointer(new->pub.proberesp_ies)) { 1610 const struct cfg80211_bss_ies *old; 1611 1612 old = rcu_access_pointer(known->pub.proberesp_ies); 1613 1614 rcu_assign_pointer(known->pub.proberesp_ies, 1615 new->pub.proberesp_ies); 1616 /* Override possible earlier Beacon frame IEs */ 1617 rcu_assign_pointer(known->pub.ies, 1618 new->pub.proberesp_ies); 1619 if (old) 1620 kfree_rcu((struct cfg80211_bss_ies *)old, rcu_head); 1621 } else if (rcu_access_pointer(new->pub.beacon_ies)) { 1622 const struct cfg80211_bss_ies *old; 1623 struct cfg80211_internal_bss *bss; 1624 1625 if (known->pub.hidden_beacon_bss && 1626 !list_empty(&known->hidden_list)) { 1627 const struct cfg80211_bss_ies *f; 1628 1629 /* The known BSS struct is one of the probe 1630 * response members of a group, but we're 1631 * receiving a beacon (beacon_ies in the new 1632 * bss is used). This can only mean that the 1633 * AP changed its beacon from not having an 1634 * SSID to showing it, which is confusing so 1635 * drop this information. 1636 */ 1637 1638 f = rcu_access_pointer(new->pub.beacon_ies); 1639 kfree_rcu((struct cfg80211_bss_ies *)f, rcu_head); 1640 return false; 1641 } 1642 1643 old = rcu_access_pointer(known->pub.beacon_ies); 1644 1645 rcu_assign_pointer(known->pub.beacon_ies, new->pub.beacon_ies); 1646 1647 /* Override IEs if they were from a beacon before */ 1648 if (old == rcu_access_pointer(known->pub.ies)) 1649 rcu_assign_pointer(known->pub.ies, new->pub.beacon_ies); 1650 1651 /* Assign beacon IEs to all sub entries */ 1652 list_for_each_entry(bss, &known->hidden_list, hidden_list) { 1653 const struct cfg80211_bss_ies *ies; 1654 1655 ies = rcu_access_pointer(bss->pub.beacon_ies); 1656 WARN_ON(ies != old); 1657 1658 rcu_assign_pointer(bss->pub.beacon_ies, 1659 new->pub.beacon_ies); 1660 } 1661 1662 if (old) 1663 kfree_rcu((struct cfg80211_bss_ies *)old, rcu_head); 1664 } 1665 1666 known->pub.beacon_interval = new->pub.beacon_interval; 1667 1668 /* don't update the signal if beacon was heard on 1669 * adjacent channel. 1670 */ 1671 if (signal_valid) 1672 known->pub.signal = new->pub.signal; 1673 known->pub.capability = new->pub.capability; 1674 known->ts = new->ts; 1675 known->ts_boottime = new->ts_boottime; 1676 known->parent_tsf = new->parent_tsf; 1677 known->pub.chains = new->pub.chains; 1678 memcpy(known->pub.chain_signal, new->pub.chain_signal, 1679 IEEE80211_MAX_CHAINS); 1680 ether_addr_copy(known->parent_bssid, new->parent_bssid); 1681 known->pub.max_bssid_indicator = new->pub.max_bssid_indicator; 1682 known->pub.bssid_index = new->pub.bssid_index; 1683 1684 return true; 1685 } 1686 1687 /* Returned bss is reference counted and must be cleaned up appropriately. */ 1688 struct cfg80211_internal_bss * 1689 cfg80211_bss_update(struct cfg80211_registered_device *rdev, 1690 struct cfg80211_internal_bss *tmp, 1691 bool signal_valid, unsigned long ts) 1692 { 1693 struct cfg80211_internal_bss *found = NULL; 1694 1695 if (WARN_ON(!tmp->pub.channel)) 1696 return NULL; 1697 1698 tmp->ts = ts; 1699 1700 spin_lock_bh(&rdev->bss_lock); 1701 1702 if (WARN_ON(!rcu_access_pointer(tmp->pub.ies))) { 1703 spin_unlock_bh(&rdev->bss_lock); 1704 return NULL; 1705 } 1706 1707 found = rb_find_bss(rdev, tmp, BSS_CMP_REGULAR); 1708 1709 if (found) { 1710 if (!cfg80211_update_known_bss(rdev, found, tmp, signal_valid)) 1711 goto drop; 1712 } else { 1713 struct cfg80211_internal_bss *new; 1714 struct cfg80211_internal_bss *hidden; 1715 struct cfg80211_bss_ies *ies; 1716 1717 /* 1718 * create a copy -- the "res" variable that is passed in 1719 * is allocated on the stack since it's not needed in the 1720 * more common case of an update 1721 */ 1722 new = kzalloc(sizeof(*new) + rdev->wiphy.bss_priv_size, 1723 GFP_ATOMIC); 1724 if (!new) { 1725 ies = (void *)rcu_dereference(tmp->pub.beacon_ies); 1726 if (ies) 1727 kfree_rcu(ies, rcu_head); 1728 ies = (void *)rcu_dereference(tmp->pub.proberesp_ies); 1729 if (ies) 1730 kfree_rcu(ies, rcu_head); 1731 goto drop; 1732 } 1733 memcpy(new, tmp, sizeof(*new)); 1734 new->refcount = 1; 1735 INIT_LIST_HEAD(&new->hidden_list); 1736 INIT_LIST_HEAD(&new->pub.nontrans_list); 1737 1738 if (rcu_access_pointer(tmp->pub.proberesp_ies)) { 1739 hidden = rb_find_bss(rdev, tmp, BSS_CMP_HIDE_ZLEN); 1740 if (!hidden) 1741 hidden = rb_find_bss(rdev, tmp, 1742 BSS_CMP_HIDE_NUL); 1743 if (hidden) { 1744 new->pub.hidden_beacon_bss = &hidden->pub; 1745 list_add(&new->hidden_list, 1746 &hidden->hidden_list); 1747 hidden->refcount++; 1748 rcu_assign_pointer(new->pub.beacon_ies, 1749 hidden->pub.beacon_ies); 1750 } 1751 } else { 1752 /* 1753 * Ok so we found a beacon, and don't have an entry. If 1754 * it's a beacon with hidden SSID, we might be in for an 1755 * expensive search for any probe responses that should 1756 * be grouped with this beacon for updates ... 1757 */ 1758 if (!cfg80211_combine_bsses(rdev, new)) { 1759 bss_ref_put(rdev, new); 1760 goto drop; 1761 } 1762 } 1763 1764 if (rdev->bss_entries >= bss_entries_limit && 1765 !cfg80211_bss_expire_oldest(rdev)) { 1766 bss_ref_put(rdev, new); 1767 goto drop; 1768 } 1769 1770 /* This must be before the call to bss_ref_get */ 1771 if (tmp->pub.transmitted_bss) { 1772 struct cfg80211_internal_bss *pbss = 1773 container_of(tmp->pub.transmitted_bss, 1774 struct cfg80211_internal_bss, 1775 pub); 1776 1777 new->pub.transmitted_bss = tmp->pub.transmitted_bss; 1778 bss_ref_get(rdev, pbss); 1779 } 1780 1781 list_add_tail(&new->list, &rdev->bss_list); 1782 rdev->bss_entries++; 1783 rb_insert_bss(rdev, new); 1784 found = new; 1785 } 1786 1787 rdev->bss_generation++; 1788 bss_ref_get(rdev, found); 1789 spin_unlock_bh(&rdev->bss_lock); 1790 1791 return found; 1792 drop: 1793 spin_unlock_bh(&rdev->bss_lock); 1794 return NULL; 1795 } 1796 1797 int cfg80211_get_ies_channel_number(const u8 *ie, size_t ielen, 1798 enum nl80211_band band) 1799 { 1800 const u8 *tmp; 1801 int channel_number = -1; 1802 1803 if (band == NL80211_BAND_S1GHZ) { 1804 tmp = cfg80211_find_ie(WLAN_EID_S1G_OPERATION, ie, ielen); 1805 if (tmp && tmp[1] >= sizeof(struct ieee80211_s1g_oper_ie)) { 1806 struct ieee80211_s1g_oper_ie *s1gop = (void *)(tmp + 2); 1807 1808 channel_number = s1gop->primary_ch; 1809 } 1810 } else { 1811 tmp = cfg80211_find_ie(WLAN_EID_DS_PARAMS, ie, ielen); 1812 if (tmp && tmp[1] == 1) { 1813 channel_number = tmp[2]; 1814 } else { 1815 tmp = cfg80211_find_ie(WLAN_EID_HT_OPERATION, ie, ielen); 1816 if (tmp && tmp[1] >= sizeof(struct ieee80211_ht_operation)) { 1817 struct ieee80211_ht_operation *htop = (void *)(tmp + 2); 1818 1819 channel_number = htop->primary_chan; 1820 } 1821 } 1822 } 1823 1824 return channel_number; 1825 } 1826 EXPORT_SYMBOL(cfg80211_get_ies_channel_number); 1827 1828 /* 1829 * Update RX channel information based on the available frame payload 1830 * information. This is mainly for the 2.4 GHz band where frames can be received 1831 * from neighboring channels and the Beacon frames use the DSSS Parameter Set 1832 * element to indicate the current (transmitting) channel, but this might also 1833 * be needed on other bands if RX frequency does not match with the actual 1834 * operating channel of a BSS. 1835 */ 1836 static struct ieee80211_channel * 1837 cfg80211_get_bss_channel(struct wiphy *wiphy, const u8 *ie, size_t ielen, 1838 struct ieee80211_channel *channel, 1839 enum nl80211_bss_scan_width scan_width) 1840 { 1841 u32 freq; 1842 int channel_number; 1843 struct ieee80211_channel *alt_channel; 1844 1845 channel_number = cfg80211_get_ies_channel_number(ie, ielen, channel->band); 1846 1847 if (channel_number < 0) { 1848 /* No channel information in frame payload */ 1849 return channel; 1850 } 1851 1852 freq = ieee80211_channel_to_freq_khz(channel_number, channel->band); 1853 alt_channel = ieee80211_get_channel_khz(wiphy, freq); 1854 if (!alt_channel) { 1855 if (channel->band == NL80211_BAND_2GHZ) { 1856 /* 1857 * Better not allow unexpected channels when that could 1858 * be going beyond the 1-11 range (e.g., discovering 1859 * BSS on channel 12 when radio is configured for 1860 * channel 11. 1861 */ 1862 return NULL; 1863 } 1864 1865 /* No match for the payload channel number - ignore it */ 1866 return channel; 1867 } 1868 1869 if (scan_width == NL80211_BSS_CHAN_WIDTH_10 || 1870 scan_width == NL80211_BSS_CHAN_WIDTH_5) { 1871 /* 1872 * Ignore channel number in 5 and 10 MHz channels where there 1873 * may not be an n:1 or 1:n mapping between frequencies and 1874 * channel numbers. 1875 */ 1876 return channel; 1877 } 1878 1879 /* 1880 * Use the channel determined through the payload channel number 1881 * instead of the RX channel reported by the driver. 1882 */ 1883 if (alt_channel->flags & IEEE80211_CHAN_DISABLED) 1884 return NULL; 1885 return alt_channel; 1886 } 1887 1888 /* Returned bss is reference counted and must be cleaned up appropriately. */ 1889 static struct cfg80211_bss * 1890 cfg80211_inform_single_bss_data(struct wiphy *wiphy, 1891 struct cfg80211_inform_bss *data, 1892 enum cfg80211_bss_frame_type ftype, 1893 const u8 *bssid, u64 tsf, u16 capability, 1894 u16 beacon_interval, const u8 *ie, size_t ielen, 1895 struct cfg80211_non_tx_bss *non_tx_data, 1896 gfp_t gfp) 1897 { 1898 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy); 1899 struct cfg80211_bss_ies *ies; 1900 struct ieee80211_channel *channel; 1901 struct cfg80211_internal_bss tmp = {}, *res; 1902 int bss_type; 1903 bool signal_valid; 1904 unsigned long ts; 1905 1906 if (WARN_ON(!wiphy)) 1907 return NULL; 1908 1909 if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC && 1910 (data->signal < 0 || data->signal > 100))) 1911 return NULL; 1912 1913 channel = cfg80211_get_bss_channel(wiphy, ie, ielen, data->chan, 1914 data->scan_width); 1915 if (!channel) 1916 return NULL; 1917 1918 memcpy(tmp.pub.bssid, bssid, ETH_ALEN); 1919 tmp.pub.channel = channel; 1920 tmp.pub.scan_width = data->scan_width; 1921 tmp.pub.signal = data->signal; 1922 tmp.pub.beacon_interval = beacon_interval; 1923 tmp.pub.capability = capability; 1924 tmp.ts_boottime = data->boottime_ns; 1925 tmp.parent_tsf = data->parent_tsf; 1926 ether_addr_copy(tmp.parent_bssid, data->parent_bssid); 1927 1928 if (non_tx_data) { 1929 tmp.pub.transmitted_bss = non_tx_data->tx_bss; 1930 ts = bss_from_pub(non_tx_data->tx_bss)->ts; 1931 tmp.pub.bssid_index = non_tx_data->bssid_index; 1932 tmp.pub.max_bssid_indicator = non_tx_data->max_bssid_indicator; 1933 } else { 1934 ts = jiffies; 1935 } 1936 1937 /* 1938 * If we do not know here whether the IEs are from a Beacon or Probe 1939 * Response frame, we need to pick one of the options and only use it 1940 * with the driver that does not provide the full Beacon/Probe Response 1941 * frame. Use Beacon frame pointer to avoid indicating that this should 1942 * override the IEs pointer should we have received an earlier 1943 * indication of Probe Response data. 1944 */ 1945 ies = kzalloc(sizeof(*ies) + ielen, gfp); 1946 if (!ies) 1947 return NULL; 1948 ies->len = ielen; 1949 ies->tsf = tsf; 1950 ies->from_beacon = false; 1951 memcpy(ies->data, ie, ielen); 1952 1953 switch (ftype) { 1954 case CFG80211_BSS_FTYPE_BEACON: 1955 ies->from_beacon = true; 1956 fallthrough; 1957 case CFG80211_BSS_FTYPE_UNKNOWN: 1958 rcu_assign_pointer(tmp.pub.beacon_ies, ies); 1959 break; 1960 case CFG80211_BSS_FTYPE_PRESP: 1961 rcu_assign_pointer(tmp.pub.proberesp_ies, ies); 1962 break; 1963 } 1964 rcu_assign_pointer(tmp.pub.ies, ies); 1965 1966 signal_valid = data->chan == channel; 1967 res = cfg80211_bss_update(wiphy_to_rdev(wiphy), &tmp, signal_valid, ts); 1968 if (!res) 1969 return NULL; 1970 1971 if (channel->band == NL80211_BAND_60GHZ) { 1972 bss_type = res->pub.capability & WLAN_CAPABILITY_DMG_TYPE_MASK; 1973 if (bss_type == WLAN_CAPABILITY_DMG_TYPE_AP || 1974 bss_type == WLAN_CAPABILITY_DMG_TYPE_PBSS) 1975 regulatory_hint_found_beacon(wiphy, channel, gfp); 1976 } else { 1977 if (res->pub.capability & WLAN_CAPABILITY_ESS) 1978 regulatory_hint_found_beacon(wiphy, channel, gfp); 1979 } 1980 1981 if (non_tx_data) { 1982 /* this is a nontransmitting bss, we need to add it to 1983 * transmitting bss' list if it is not there 1984 */ 1985 if (cfg80211_add_nontrans_list(non_tx_data->tx_bss, 1986 &res->pub)) { 1987 if (__cfg80211_unlink_bss(rdev, res)) 1988 rdev->bss_generation++; 1989 } 1990 } 1991 1992 trace_cfg80211_return_bss(&res->pub); 1993 /* cfg80211_bss_update gives us a referenced result */ 1994 return &res->pub; 1995 } 1996 1997 static const struct element 1998 *cfg80211_get_profile_continuation(const u8 *ie, size_t ielen, 1999 const struct element *mbssid_elem, 2000 const struct element *sub_elem) 2001 { 2002 const u8 *mbssid_end = mbssid_elem->data + mbssid_elem->datalen; 2003 const struct element *next_mbssid; 2004 const struct element *next_sub; 2005 2006 next_mbssid = cfg80211_find_elem(WLAN_EID_MULTIPLE_BSSID, 2007 mbssid_end, 2008 ielen - (mbssid_end - ie)); 2009 2010 /* 2011 * If it is not the last subelement in current MBSSID IE or there isn't 2012 * a next MBSSID IE - profile is complete. 2013 */ 2014 if ((sub_elem->data + sub_elem->datalen < mbssid_end - 1) || 2015 !next_mbssid) 2016 return NULL; 2017 2018 /* For any length error, just return NULL */ 2019 2020 if (next_mbssid->datalen < 4) 2021 return NULL; 2022 2023 next_sub = (void *)&next_mbssid->data[1]; 2024 2025 if (next_mbssid->data + next_mbssid->datalen < 2026 next_sub->data + next_sub->datalen) 2027 return NULL; 2028 2029 if (next_sub->id != 0 || next_sub->datalen < 2) 2030 return NULL; 2031 2032 /* 2033 * Check if the first element in the next sub element is a start 2034 * of a new profile 2035 */ 2036 return next_sub->data[0] == WLAN_EID_NON_TX_BSSID_CAP ? 2037 NULL : next_mbssid; 2038 } 2039 2040 size_t cfg80211_merge_profile(const u8 *ie, size_t ielen, 2041 const struct element *mbssid_elem, 2042 const struct element *sub_elem, 2043 u8 *merged_ie, size_t max_copy_len) 2044 { 2045 size_t copied_len = sub_elem->datalen; 2046 const struct element *next_mbssid; 2047 2048 if (sub_elem->datalen > max_copy_len) 2049 return 0; 2050 2051 memcpy(merged_ie, sub_elem->data, sub_elem->datalen); 2052 2053 while ((next_mbssid = cfg80211_get_profile_continuation(ie, ielen, 2054 mbssid_elem, 2055 sub_elem))) { 2056 const struct element *next_sub = (void *)&next_mbssid->data[1]; 2057 2058 if (copied_len + next_sub->datalen > max_copy_len) 2059 break; 2060 memcpy(merged_ie + copied_len, next_sub->data, 2061 next_sub->datalen); 2062 copied_len += next_sub->datalen; 2063 } 2064 2065 return copied_len; 2066 } 2067 EXPORT_SYMBOL(cfg80211_merge_profile); 2068 2069 static void cfg80211_parse_mbssid_data(struct wiphy *wiphy, 2070 struct cfg80211_inform_bss *data, 2071 enum cfg80211_bss_frame_type ftype, 2072 const u8 *bssid, u64 tsf, 2073 u16 beacon_interval, const u8 *ie, 2074 size_t ielen, 2075 struct cfg80211_non_tx_bss *non_tx_data, 2076 gfp_t gfp) 2077 { 2078 const u8 *mbssid_index_ie; 2079 const struct element *elem, *sub; 2080 size_t new_ie_len; 2081 u8 new_bssid[ETH_ALEN]; 2082 u8 *new_ie, *profile; 2083 u64 seen_indices = 0; 2084 u16 capability; 2085 struct cfg80211_bss *bss; 2086 2087 if (!non_tx_data) 2088 return; 2089 if (!cfg80211_find_elem(WLAN_EID_MULTIPLE_BSSID, ie, ielen)) 2090 return; 2091 if (!wiphy->support_mbssid) 2092 return; 2093 if (wiphy->support_only_he_mbssid && 2094 !cfg80211_find_ext_elem(WLAN_EID_EXT_HE_CAPABILITY, ie, ielen)) 2095 return; 2096 2097 new_ie = kmalloc(IEEE80211_MAX_DATA_LEN, gfp); 2098 if (!new_ie) 2099 return; 2100 2101 profile = kmalloc(ielen, gfp); 2102 if (!profile) 2103 goto out; 2104 2105 for_each_element_id(elem, WLAN_EID_MULTIPLE_BSSID, ie, ielen) { 2106 if (elem->datalen < 4) 2107 continue; 2108 for_each_element(sub, elem->data + 1, elem->datalen - 1) { 2109 u8 profile_len; 2110 2111 if (sub->id != 0 || sub->datalen < 4) { 2112 /* not a valid BSS profile */ 2113 continue; 2114 } 2115 2116 if (sub->data[0] != WLAN_EID_NON_TX_BSSID_CAP || 2117 sub->data[1] != 2) { 2118 /* The first element within the Nontransmitted 2119 * BSSID Profile is not the Nontransmitted 2120 * BSSID Capability element. 2121 */ 2122 continue; 2123 } 2124 2125 memset(profile, 0, ielen); 2126 profile_len = cfg80211_merge_profile(ie, ielen, 2127 elem, 2128 sub, 2129 profile, 2130 ielen); 2131 2132 /* found a Nontransmitted BSSID Profile */ 2133 mbssid_index_ie = cfg80211_find_ie 2134 (WLAN_EID_MULTI_BSSID_IDX, 2135 profile, profile_len); 2136 if (!mbssid_index_ie || mbssid_index_ie[1] < 1 || 2137 mbssid_index_ie[2] == 0 || 2138 mbssid_index_ie[2] > 46) { 2139 /* No valid Multiple BSSID-Index element */ 2140 continue; 2141 } 2142 2143 if (seen_indices & BIT_ULL(mbssid_index_ie[2])) 2144 /* We don't support legacy split of a profile */ 2145 net_dbg_ratelimited("Partial info for BSSID index %d\n", 2146 mbssid_index_ie[2]); 2147 2148 seen_indices |= BIT_ULL(mbssid_index_ie[2]); 2149 2150 non_tx_data->bssid_index = mbssid_index_ie[2]; 2151 non_tx_data->max_bssid_indicator = elem->data[0]; 2152 2153 cfg80211_gen_new_bssid(bssid, 2154 non_tx_data->max_bssid_indicator, 2155 non_tx_data->bssid_index, 2156 new_bssid); 2157 memset(new_ie, 0, IEEE80211_MAX_DATA_LEN); 2158 new_ie_len = cfg80211_gen_new_ie(ie, ielen, 2159 profile, 2160 profile_len, new_ie, 2161 gfp); 2162 if (!new_ie_len) 2163 continue; 2164 2165 capability = get_unaligned_le16(profile + 2); 2166 bss = cfg80211_inform_single_bss_data(wiphy, data, 2167 ftype, 2168 new_bssid, tsf, 2169 capability, 2170 beacon_interval, 2171 new_ie, 2172 new_ie_len, 2173 non_tx_data, 2174 gfp); 2175 if (!bss) 2176 break; 2177 cfg80211_put_bss(wiphy, bss); 2178 } 2179 } 2180 2181 out: 2182 kfree(new_ie); 2183 kfree(profile); 2184 } 2185 2186 struct cfg80211_bss * 2187 cfg80211_inform_bss_data(struct wiphy *wiphy, 2188 struct cfg80211_inform_bss *data, 2189 enum cfg80211_bss_frame_type ftype, 2190 const u8 *bssid, u64 tsf, u16 capability, 2191 u16 beacon_interval, const u8 *ie, size_t ielen, 2192 gfp_t gfp) 2193 { 2194 struct cfg80211_bss *res; 2195 struct cfg80211_non_tx_bss non_tx_data; 2196 2197 res = cfg80211_inform_single_bss_data(wiphy, data, ftype, bssid, tsf, 2198 capability, beacon_interval, ie, 2199 ielen, NULL, gfp); 2200 if (!res) 2201 return NULL; 2202 non_tx_data.tx_bss = res; 2203 cfg80211_parse_mbssid_data(wiphy, data, ftype, bssid, tsf, 2204 beacon_interval, ie, ielen, &non_tx_data, 2205 gfp); 2206 return res; 2207 } 2208 EXPORT_SYMBOL(cfg80211_inform_bss_data); 2209 2210 static void 2211 cfg80211_parse_mbssid_frame_data(struct wiphy *wiphy, 2212 struct cfg80211_inform_bss *data, 2213 struct ieee80211_mgmt *mgmt, size_t len, 2214 struct cfg80211_non_tx_bss *non_tx_data, 2215 gfp_t gfp) 2216 { 2217 enum cfg80211_bss_frame_type ftype; 2218 const u8 *ie = mgmt->u.probe_resp.variable; 2219 size_t ielen = len - offsetof(struct ieee80211_mgmt, 2220 u.probe_resp.variable); 2221 2222 ftype = ieee80211_is_beacon(mgmt->frame_control) ? 2223 CFG80211_BSS_FTYPE_BEACON : CFG80211_BSS_FTYPE_PRESP; 2224 2225 cfg80211_parse_mbssid_data(wiphy, data, ftype, mgmt->bssid, 2226 le64_to_cpu(mgmt->u.probe_resp.timestamp), 2227 le16_to_cpu(mgmt->u.probe_resp.beacon_int), 2228 ie, ielen, non_tx_data, gfp); 2229 } 2230 2231 static void 2232 cfg80211_update_notlisted_nontrans(struct wiphy *wiphy, 2233 struct cfg80211_bss *nontrans_bss, 2234 struct ieee80211_mgmt *mgmt, size_t len) 2235 { 2236 u8 *ie, *new_ie, *pos; 2237 const u8 *nontrans_ssid, *trans_ssid, *mbssid; 2238 size_t ielen = len - offsetof(struct ieee80211_mgmt, 2239 u.probe_resp.variable); 2240 size_t new_ie_len; 2241 struct cfg80211_bss_ies *new_ies; 2242 const struct cfg80211_bss_ies *old; 2243 u8 cpy_len; 2244 2245 lockdep_assert_held(&wiphy_to_rdev(wiphy)->bss_lock); 2246 2247 ie = mgmt->u.probe_resp.variable; 2248 2249 new_ie_len = ielen; 2250 trans_ssid = cfg80211_find_ie(WLAN_EID_SSID, ie, ielen); 2251 if (!trans_ssid) 2252 return; 2253 new_ie_len -= trans_ssid[1]; 2254 mbssid = cfg80211_find_ie(WLAN_EID_MULTIPLE_BSSID, ie, ielen); 2255 /* 2256 * It's not valid to have the MBSSID element before SSID 2257 * ignore if that happens - the code below assumes it is 2258 * after (while copying things inbetween). 2259 */ 2260 if (!mbssid || mbssid < trans_ssid) 2261 return; 2262 new_ie_len -= mbssid[1]; 2263 2264 nontrans_ssid = ieee80211_bss_get_ie(nontrans_bss, WLAN_EID_SSID); 2265 if (!nontrans_ssid) 2266 return; 2267 2268 new_ie_len += nontrans_ssid[1]; 2269 2270 /* generate new ie for nontrans BSS 2271 * 1. replace SSID with nontrans BSS' SSID 2272 * 2. skip MBSSID IE 2273 */ 2274 new_ie = kzalloc(new_ie_len, GFP_ATOMIC); 2275 if (!new_ie) 2276 return; 2277 2278 new_ies = kzalloc(sizeof(*new_ies) + new_ie_len, GFP_ATOMIC); 2279 if (!new_ies) 2280 goto out_free; 2281 2282 pos = new_ie; 2283 2284 /* copy the nontransmitted SSID */ 2285 cpy_len = nontrans_ssid[1] + 2; 2286 memcpy(pos, nontrans_ssid, cpy_len); 2287 pos += cpy_len; 2288 /* copy the IEs between SSID and MBSSID */ 2289 cpy_len = trans_ssid[1] + 2; 2290 memcpy(pos, (trans_ssid + cpy_len), (mbssid - (trans_ssid + cpy_len))); 2291 pos += (mbssid - (trans_ssid + cpy_len)); 2292 /* copy the IEs after MBSSID */ 2293 cpy_len = mbssid[1] + 2; 2294 memcpy(pos, mbssid + cpy_len, ((ie + ielen) - (mbssid + cpy_len))); 2295 2296 /* update ie */ 2297 new_ies->len = new_ie_len; 2298 new_ies->tsf = le64_to_cpu(mgmt->u.probe_resp.timestamp); 2299 new_ies->from_beacon = ieee80211_is_beacon(mgmt->frame_control); 2300 memcpy(new_ies->data, new_ie, new_ie_len); 2301 if (ieee80211_is_probe_resp(mgmt->frame_control)) { 2302 old = rcu_access_pointer(nontrans_bss->proberesp_ies); 2303 rcu_assign_pointer(nontrans_bss->proberesp_ies, new_ies); 2304 rcu_assign_pointer(nontrans_bss->ies, new_ies); 2305 if (old) 2306 kfree_rcu((struct cfg80211_bss_ies *)old, rcu_head); 2307 } else { 2308 old = rcu_access_pointer(nontrans_bss->beacon_ies); 2309 rcu_assign_pointer(nontrans_bss->beacon_ies, new_ies); 2310 rcu_assign_pointer(nontrans_bss->ies, new_ies); 2311 if (old) 2312 kfree_rcu((struct cfg80211_bss_ies *)old, rcu_head); 2313 } 2314 2315 out_free: 2316 kfree(new_ie); 2317 } 2318 2319 /* cfg80211_inform_bss_width_frame helper */ 2320 static struct cfg80211_bss * 2321 cfg80211_inform_single_bss_frame_data(struct wiphy *wiphy, 2322 struct cfg80211_inform_bss *data, 2323 struct ieee80211_mgmt *mgmt, size_t len, 2324 gfp_t gfp) 2325 { 2326 struct cfg80211_internal_bss tmp = {}, *res; 2327 struct cfg80211_bss_ies *ies; 2328 struct ieee80211_channel *channel; 2329 bool signal_valid; 2330 struct ieee80211_ext *ext = NULL; 2331 u8 *bssid, *variable; 2332 u16 capability, beacon_int; 2333 size_t ielen, min_hdr_len = offsetof(struct ieee80211_mgmt, 2334 u.probe_resp.variable); 2335 int bss_type; 2336 2337 BUILD_BUG_ON(offsetof(struct ieee80211_mgmt, u.probe_resp.variable) != 2338 offsetof(struct ieee80211_mgmt, u.beacon.variable)); 2339 2340 trace_cfg80211_inform_bss_frame(wiphy, data, mgmt, len); 2341 2342 if (WARN_ON(!mgmt)) 2343 return NULL; 2344 2345 if (WARN_ON(!wiphy)) 2346 return NULL; 2347 2348 if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC && 2349 (data->signal < 0 || data->signal > 100))) 2350 return NULL; 2351 2352 if (ieee80211_is_s1g_beacon(mgmt->frame_control)) { 2353 ext = (void *) mgmt; 2354 min_hdr_len = offsetof(struct ieee80211_ext, u.s1g_beacon); 2355 if (ieee80211_is_s1g_short_beacon(mgmt->frame_control)) 2356 min_hdr_len = offsetof(struct ieee80211_ext, 2357 u.s1g_short_beacon.variable); 2358 } 2359 2360 if (WARN_ON(len < min_hdr_len)) 2361 return NULL; 2362 2363 ielen = len - min_hdr_len; 2364 variable = mgmt->u.probe_resp.variable; 2365 if (ext) { 2366 if (ieee80211_is_s1g_short_beacon(mgmt->frame_control)) 2367 variable = ext->u.s1g_short_beacon.variable; 2368 else 2369 variable = ext->u.s1g_beacon.variable; 2370 } 2371 2372 channel = cfg80211_get_bss_channel(wiphy, variable, 2373 ielen, data->chan, data->scan_width); 2374 if (!channel) 2375 return NULL; 2376 2377 if (ext) { 2378 const struct ieee80211_s1g_bcn_compat_ie *compat; 2379 const struct element *elem; 2380 2381 elem = cfg80211_find_elem(WLAN_EID_S1G_BCN_COMPAT, 2382 variable, ielen); 2383 if (!elem) 2384 return NULL; 2385 if (elem->datalen < sizeof(*compat)) 2386 return NULL; 2387 compat = (void *)elem->data; 2388 bssid = ext->u.s1g_beacon.sa; 2389 capability = le16_to_cpu(compat->compat_info); 2390 beacon_int = le16_to_cpu(compat->beacon_int); 2391 } else { 2392 bssid = mgmt->bssid; 2393 beacon_int = le16_to_cpu(mgmt->u.probe_resp.beacon_int); 2394 capability = le16_to_cpu(mgmt->u.probe_resp.capab_info); 2395 } 2396 2397 ies = kzalloc(sizeof(*ies) + ielen, gfp); 2398 if (!ies) 2399 return NULL; 2400 ies->len = ielen; 2401 ies->tsf = le64_to_cpu(mgmt->u.probe_resp.timestamp); 2402 ies->from_beacon = ieee80211_is_beacon(mgmt->frame_control) || 2403 ieee80211_is_s1g_beacon(mgmt->frame_control); 2404 memcpy(ies->data, variable, ielen); 2405 2406 if (ieee80211_is_probe_resp(mgmt->frame_control)) 2407 rcu_assign_pointer(tmp.pub.proberesp_ies, ies); 2408 else 2409 rcu_assign_pointer(tmp.pub.beacon_ies, ies); 2410 rcu_assign_pointer(tmp.pub.ies, ies); 2411 2412 memcpy(tmp.pub.bssid, bssid, ETH_ALEN); 2413 tmp.pub.beacon_interval = beacon_int; 2414 tmp.pub.capability = capability; 2415 tmp.pub.channel = channel; 2416 tmp.pub.scan_width = data->scan_width; 2417 tmp.pub.signal = data->signal; 2418 tmp.ts_boottime = data->boottime_ns; 2419 tmp.parent_tsf = data->parent_tsf; 2420 tmp.pub.chains = data->chains; 2421 memcpy(tmp.pub.chain_signal, data->chain_signal, IEEE80211_MAX_CHAINS); 2422 ether_addr_copy(tmp.parent_bssid, data->parent_bssid); 2423 2424 signal_valid = data->chan == channel; 2425 res = cfg80211_bss_update(wiphy_to_rdev(wiphy), &tmp, signal_valid, 2426 jiffies); 2427 if (!res) 2428 return NULL; 2429 2430 if (channel->band == NL80211_BAND_60GHZ) { 2431 bss_type = res->pub.capability & WLAN_CAPABILITY_DMG_TYPE_MASK; 2432 if (bss_type == WLAN_CAPABILITY_DMG_TYPE_AP || 2433 bss_type == WLAN_CAPABILITY_DMG_TYPE_PBSS) 2434 regulatory_hint_found_beacon(wiphy, channel, gfp); 2435 } else { 2436 if (res->pub.capability & WLAN_CAPABILITY_ESS) 2437 regulatory_hint_found_beacon(wiphy, channel, gfp); 2438 } 2439 2440 trace_cfg80211_return_bss(&res->pub); 2441 /* cfg80211_bss_update gives us a referenced result */ 2442 return &res->pub; 2443 } 2444 2445 struct cfg80211_bss * 2446 cfg80211_inform_bss_frame_data(struct wiphy *wiphy, 2447 struct cfg80211_inform_bss *data, 2448 struct ieee80211_mgmt *mgmt, size_t len, 2449 gfp_t gfp) 2450 { 2451 struct cfg80211_bss *res, *tmp_bss; 2452 const u8 *ie = mgmt->u.probe_resp.variable; 2453 const struct cfg80211_bss_ies *ies1, *ies2; 2454 size_t ielen = len - offsetof(struct ieee80211_mgmt, 2455 u.probe_resp.variable); 2456 struct cfg80211_non_tx_bss non_tx_data; 2457 2458 res = cfg80211_inform_single_bss_frame_data(wiphy, data, mgmt, 2459 len, gfp); 2460 if (!res || !wiphy->support_mbssid || 2461 !cfg80211_find_elem(WLAN_EID_MULTIPLE_BSSID, ie, ielen)) 2462 return res; 2463 if (wiphy->support_only_he_mbssid && 2464 !cfg80211_find_ext_elem(WLAN_EID_EXT_HE_CAPABILITY, ie, ielen)) 2465 return res; 2466 2467 non_tx_data.tx_bss = res; 2468 /* process each non-transmitting bss */ 2469 cfg80211_parse_mbssid_frame_data(wiphy, data, mgmt, len, 2470 &non_tx_data, gfp); 2471 2472 spin_lock_bh(&wiphy_to_rdev(wiphy)->bss_lock); 2473 2474 /* check if the res has other nontransmitting bss which is not 2475 * in MBSSID IE 2476 */ 2477 ies1 = rcu_access_pointer(res->ies); 2478 2479 /* go through nontrans_list, if the timestamp of the BSS is 2480 * earlier than the timestamp of the transmitting BSS then 2481 * update it 2482 */ 2483 list_for_each_entry(tmp_bss, &res->nontrans_list, 2484 nontrans_list) { 2485 ies2 = rcu_access_pointer(tmp_bss->ies); 2486 if (ies2->tsf < ies1->tsf) 2487 cfg80211_update_notlisted_nontrans(wiphy, tmp_bss, 2488 mgmt, len); 2489 } 2490 spin_unlock_bh(&wiphy_to_rdev(wiphy)->bss_lock); 2491 2492 return res; 2493 } 2494 EXPORT_SYMBOL(cfg80211_inform_bss_frame_data); 2495 2496 void cfg80211_ref_bss(struct wiphy *wiphy, struct cfg80211_bss *pub) 2497 { 2498 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy); 2499 struct cfg80211_internal_bss *bss; 2500 2501 if (!pub) 2502 return; 2503 2504 bss = container_of(pub, struct cfg80211_internal_bss, pub); 2505 2506 spin_lock_bh(&rdev->bss_lock); 2507 bss_ref_get(rdev, bss); 2508 spin_unlock_bh(&rdev->bss_lock); 2509 } 2510 EXPORT_SYMBOL(cfg80211_ref_bss); 2511 2512 void cfg80211_put_bss(struct wiphy *wiphy, struct cfg80211_bss *pub) 2513 { 2514 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy); 2515 struct cfg80211_internal_bss *bss; 2516 2517 if (!pub) 2518 return; 2519 2520 bss = container_of(pub, struct cfg80211_internal_bss, pub); 2521 2522 spin_lock_bh(&rdev->bss_lock); 2523 bss_ref_put(rdev, bss); 2524 spin_unlock_bh(&rdev->bss_lock); 2525 } 2526 EXPORT_SYMBOL(cfg80211_put_bss); 2527 2528 void cfg80211_unlink_bss(struct wiphy *wiphy, struct cfg80211_bss *pub) 2529 { 2530 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy); 2531 struct cfg80211_internal_bss *bss, *tmp1; 2532 struct cfg80211_bss *nontrans_bss, *tmp; 2533 2534 if (WARN_ON(!pub)) 2535 return; 2536 2537 bss = container_of(pub, struct cfg80211_internal_bss, pub); 2538 2539 spin_lock_bh(&rdev->bss_lock); 2540 if (list_empty(&bss->list)) 2541 goto out; 2542 2543 list_for_each_entry_safe(nontrans_bss, tmp, 2544 &pub->nontrans_list, 2545 nontrans_list) { 2546 tmp1 = container_of(nontrans_bss, 2547 struct cfg80211_internal_bss, pub); 2548 if (__cfg80211_unlink_bss(rdev, tmp1)) 2549 rdev->bss_generation++; 2550 } 2551 2552 if (__cfg80211_unlink_bss(rdev, bss)) 2553 rdev->bss_generation++; 2554 out: 2555 spin_unlock_bh(&rdev->bss_lock); 2556 } 2557 EXPORT_SYMBOL(cfg80211_unlink_bss); 2558 2559 void cfg80211_bss_iter(struct wiphy *wiphy, 2560 struct cfg80211_chan_def *chandef, 2561 void (*iter)(struct wiphy *wiphy, 2562 struct cfg80211_bss *bss, 2563 void *data), 2564 void *iter_data) 2565 { 2566 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy); 2567 struct cfg80211_internal_bss *bss; 2568 2569 spin_lock_bh(&rdev->bss_lock); 2570 2571 list_for_each_entry(bss, &rdev->bss_list, list) { 2572 if (!chandef || cfg80211_is_sub_chan(chandef, bss->pub.channel)) 2573 iter(wiphy, &bss->pub, iter_data); 2574 } 2575 2576 spin_unlock_bh(&rdev->bss_lock); 2577 } 2578 EXPORT_SYMBOL(cfg80211_bss_iter); 2579 2580 void cfg80211_update_assoc_bss_entry(struct wireless_dev *wdev, 2581 struct ieee80211_channel *chan) 2582 { 2583 struct wiphy *wiphy = wdev->wiphy; 2584 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy); 2585 struct cfg80211_internal_bss *cbss = wdev->current_bss; 2586 struct cfg80211_internal_bss *new = NULL; 2587 struct cfg80211_internal_bss *bss; 2588 struct cfg80211_bss *nontrans_bss; 2589 struct cfg80211_bss *tmp; 2590 2591 spin_lock_bh(&rdev->bss_lock); 2592 2593 /* 2594 * Some APs use CSA also for bandwidth changes, i.e., without actually 2595 * changing the control channel, so no need to update in such a case. 2596 */ 2597 if (cbss->pub.channel == chan) 2598 goto done; 2599 2600 /* use transmitting bss */ 2601 if (cbss->pub.transmitted_bss) 2602 cbss = container_of(cbss->pub.transmitted_bss, 2603 struct cfg80211_internal_bss, 2604 pub); 2605 2606 cbss->pub.channel = chan; 2607 2608 list_for_each_entry(bss, &rdev->bss_list, list) { 2609 if (!cfg80211_bss_type_match(bss->pub.capability, 2610 bss->pub.channel->band, 2611 wdev->conn_bss_type)) 2612 continue; 2613 2614 if (bss == cbss) 2615 continue; 2616 2617 if (!cmp_bss(&bss->pub, &cbss->pub, BSS_CMP_REGULAR)) { 2618 new = bss; 2619 break; 2620 } 2621 } 2622 2623 if (new) { 2624 /* to save time, update IEs for transmitting bss only */ 2625 if (cfg80211_update_known_bss(rdev, cbss, new, false)) { 2626 new->pub.proberesp_ies = NULL; 2627 new->pub.beacon_ies = NULL; 2628 } 2629 2630 list_for_each_entry_safe(nontrans_bss, tmp, 2631 &new->pub.nontrans_list, 2632 nontrans_list) { 2633 bss = container_of(nontrans_bss, 2634 struct cfg80211_internal_bss, pub); 2635 if (__cfg80211_unlink_bss(rdev, bss)) 2636 rdev->bss_generation++; 2637 } 2638 2639 WARN_ON(atomic_read(&new->hold)); 2640 if (!WARN_ON(!__cfg80211_unlink_bss(rdev, new))) 2641 rdev->bss_generation++; 2642 } 2643 2644 rb_erase(&cbss->rbn, &rdev->bss_tree); 2645 rb_insert_bss(rdev, cbss); 2646 rdev->bss_generation++; 2647 2648 list_for_each_entry_safe(nontrans_bss, tmp, 2649 &cbss->pub.nontrans_list, 2650 nontrans_list) { 2651 bss = container_of(nontrans_bss, 2652 struct cfg80211_internal_bss, pub); 2653 bss->pub.channel = chan; 2654 rb_erase(&bss->rbn, &rdev->bss_tree); 2655 rb_insert_bss(rdev, bss); 2656 rdev->bss_generation++; 2657 } 2658 2659 done: 2660 spin_unlock_bh(&rdev->bss_lock); 2661 } 2662 2663 #ifdef CONFIG_CFG80211_WEXT 2664 static struct cfg80211_registered_device * 2665 cfg80211_get_dev_from_ifindex(struct net *net, int ifindex) 2666 { 2667 struct cfg80211_registered_device *rdev; 2668 struct net_device *dev; 2669 2670 ASSERT_RTNL(); 2671 2672 dev = dev_get_by_index(net, ifindex); 2673 if (!dev) 2674 return ERR_PTR(-ENODEV); 2675 if (dev->ieee80211_ptr) 2676 rdev = wiphy_to_rdev(dev->ieee80211_ptr->wiphy); 2677 else 2678 rdev = ERR_PTR(-ENODEV); 2679 dev_put(dev); 2680 return rdev; 2681 } 2682 2683 int cfg80211_wext_siwscan(struct net_device *dev, 2684 struct iw_request_info *info, 2685 union iwreq_data *wrqu, char *extra) 2686 { 2687 struct cfg80211_registered_device *rdev; 2688 struct wiphy *wiphy; 2689 struct iw_scan_req *wreq = NULL; 2690 struct cfg80211_scan_request *creq = NULL; 2691 int i, err, n_channels = 0; 2692 enum nl80211_band band; 2693 2694 if (!netif_running(dev)) 2695 return -ENETDOWN; 2696 2697 if (wrqu->data.length == sizeof(struct iw_scan_req)) 2698 wreq = (struct iw_scan_req *)extra; 2699 2700 rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex); 2701 2702 if (IS_ERR(rdev)) 2703 return PTR_ERR(rdev); 2704 2705 if (rdev->scan_req || rdev->scan_msg) { 2706 err = -EBUSY; 2707 goto out; 2708 } 2709 2710 wiphy = &rdev->wiphy; 2711 2712 /* Determine number of channels, needed to allocate creq */ 2713 if (wreq && wreq->num_channels) 2714 n_channels = wreq->num_channels; 2715 else 2716 n_channels = ieee80211_get_num_supported_channels(wiphy); 2717 2718 creq = kzalloc(sizeof(*creq) + sizeof(struct cfg80211_ssid) + 2719 n_channels * sizeof(void *), 2720 GFP_ATOMIC); 2721 if (!creq) { 2722 err = -ENOMEM; 2723 goto out; 2724 } 2725 2726 creq->wiphy = wiphy; 2727 creq->wdev = dev->ieee80211_ptr; 2728 /* SSIDs come after channels */ 2729 creq->ssids = (void *)&creq->channels[n_channels]; 2730 creq->n_channels = n_channels; 2731 creq->n_ssids = 1; 2732 creq->scan_start = jiffies; 2733 2734 /* translate "Scan on frequencies" request */ 2735 i = 0; 2736 for (band = 0; band < NUM_NL80211_BANDS; band++) { 2737 int j; 2738 2739 if (!wiphy->bands[band]) 2740 continue; 2741 2742 for (j = 0; j < wiphy->bands[band]->n_channels; j++) { 2743 /* ignore disabled channels */ 2744 if (wiphy->bands[band]->channels[j].flags & 2745 IEEE80211_CHAN_DISABLED) 2746 continue; 2747 2748 /* If we have a wireless request structure and the 2749 * wireless request specifies frequencies, then search 2750 * for the matching hardware channel. 2751 */ 2752 if (wreq && wreq->num_channels) { 2753 int k; 2754 int wiphy_freq = wiphy->bands[band]->channels[j].center_freq; 2755 for (k = 0; k < wreq->num_channels; k++) { 2756 struct iw_freq *freq = 2757 &wreq->channel_list[k]; 2758 int wext_freq = 2759 cfg80211_wext_freq(freq); 2760 2761 if (wext_freq == wiphy_freq) 2762 goto wext_freq_found; 2763 } 2764 goto wext_freq_not_found; 2765 } 2766 2767 wext_freq_found: 2768 creq->channels[i] = &wiphy->bands[band]->channels[j]; 2769 i++; 2770 wext_freq_not_found: ; 2771 } 2772 } 2773 /* No channels found? */ 2774 if (!i) { 2775 err = -EINVAL; 2776 goto out; 2777 } 2778 2779 /* Set real number of channels specified in creq->channels[] */ 2780 creq->n_channels = i; 2781 2782 /* translate "Scan for SSID" request */ 2783 if (wreq) { 2784 if (wrqu->data.flags & IW_SCAN_THIS_ESSID) { 2785 if (wreq->essid_len > IEEE80211_MAX_SSID_LEN) { 2786 err = -EINVAL; 2787 goto out; 2788 } 2789 memcpy(creq->ssids[0].ssid, wreq->essid, wreq->essid_len); 2790 creq->ssids[0].ssid_len = wreq->essid_len; 2791 } 2792 if (wreq->scan_type == IW_SCAN_TYPE_PASSIVE) 2793 creq->n_ssids = 0; 2794 } 2795 2796 for (i = 0; i < NUM_NL80211_BANDS; i++) 2797 if (wiphy->bands[i]) 2798 creq->rates[i] = (1 << wiphy->bands[i]->n_bitrates) - 1; 2799 2800 eth_broadcast_addr(creq->bssid); 2801 2802 wiphy_lock(&rdev->wiphy); 2803 2804 rdev->scan_req = creq; 2805 err = rdev_scan(rdev, creq); 2806 if (err) { 2807 rdev->scan_req = NULL; 2808 /* creq will be freed below */ 2809 } else { 2810 nl80211_send_scan_start(rdev, dev->ieee80211_ptr); 2811 /* creq now owned by driver */ 2812 creq = NULL; 2813 dev_hold(dev); 2814 } 2815 wiphy_unlock(&rdev->wiphy); 2816 out: 2817 kfree(creq); 2818 return err; 2819 } 2820 EXPORT_WEXT_HANDLER(cfg80211_wext_siwscan); 2821 2822 static char *ieee80211_scan_add_ies(struct iw_request_info *info, 2823 const struct cfg80211_bss_ies *ies, 2824 char *current_ev, char *end_buf) 2825 { 2826 const u8 *pos, *end, *next; 2827 struct iw_event iwe; 2828 2829 if (!ies) 2830 return current_ev; 2831 2832 /* 2833 * If needed, fragment the IEs buffer (at IE boundaries) into short 2834 * enough fragments to fit into IW_GENERIC_IE_MAX octet messages. 2835 */ 2836 pos = ies->data; 2837 end = pos + ies->len; 2838 2839 while (end - pos > IW_GENERIC_IE_MAX) { 2840 next = pos + 2 + pos[1]; 2841 while (next + 2 + next[1] - pos < IW_GENERIC_IE_MAX) 2842 next = next + 2 + next[1]; 2843 2844 memset(&iwe, 0, sizeof(iwe)); 2845 iwe.cmd = IWEVGENIE; 2846 iwe.u.data.length = next - pos; 2847 current_ev = iwe_stream_add_point_check(info, current_ev, 2848 end_buf, &iwe, 2849 (void *)pos); 2850 if (IS_ERR(current_ev)) 2851 return current_ev; 2852 pos = next; 2853 } 2854 2855 if (end > pos) { 2856 memset(&iwe, 0, sizeof(iwe)); 2857 iwe.cmd = IWEVGENIE; 2858 iwe.u.data.length = end - pos; 2859 current_ev = iwe_stream_add_point_check(info, current_ev, 2860 end_buf, &iwe, 2861 (void *)pos); 2862 if (IS_ERR(current_ev)) 2863 return current_ev; 2864 } 2865 2866 return current_ev; 2867 } 2868 2869 static char * 2870 ieee80211_bss(struct wiphy *wiphy, struct iw_request_info *info, 2871 struct cfg80211_internal_bss *bss, char *current_ev, 2872 char *end_buf) 2873 { 2874 const struct cfg80211_bss_ies *ies; 2875 struct iw_event iwe; 2876 const u8 *ie; 2877 u8 buf[50]; 2878 u8 *cfg, *p, *tmp; 2879 int rem, i, sig; 2880 bool ismesh = false; 2881 2882 memset(&iwe, 0, sizeof(iwe)); 2883 iwe.cmd = SIOCGIWAP; 2884 iwe.u.ap_addr.sa_family = ARPHRD_ETHER; 2885 memcpy(iwe.u.ap_addr.sa_data, bss->pub.bssid, ETH_ALEN); 2886 current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe, 2887 IW_EV_ADDR_LEN); 2888 if (IS_ERR(current_ev)) 2889 return current_ev; 2890 2891 memset(&iwe, 0, sizeof(iwe)); 2892 iwe.cmd = SIOCGIWFREQ; 2893 iwe.u.freq.m = ieee80211_frequency_to_channel(bss->pub.channel->center_freq); 2894 iwe.u.freq.e = 0; 2895 current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe, 2896 IW_EV_FREQ_LEN); 2897 if (IS_ERR(current_ev)) 2898 return current_ev; 2899 2900 memset(&iwe, 0, sizeof(iwe)); 2901 iwe.cmd = SIOCGIWFREQ; 2902 iwe.u.freq.m = bss->pub.channel->center_freq; 2903 iwe.u.freq.e = 6; 2904 current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe, 2905 IW_EV_FREQ_LEN); 2906 if (IS_ERR(current_ev)) 2907 return current_ev; 2908 2909 if (wiphy->signal_type != CFG80211_SIGNAL_TYPE_NONE) { 2910 memset(&iwe, 0, sizeof(iwe)); 2911 iwe.cmd = IWEVQUAL; 2912 iwe.u.qual.updated = IW_QUAL_LEVEL_UPDATED | 2913 IW_QUAL_NOISE_INVALID | 2914 IW_QUAL_QUAL_UPDATED; 2915 switch (wiphy->signal_type) { 2916 case CFG80211_SIGNAL_TYPE_MBM: 2917 sig = bss->pub.signal / 100; 2918 iwe.u.qual.level = sig; 2919 iwe.u.qual.updated |= IW_QUAL_DBM; 2920 if (sig < -110) /* rather bad */ 2921 sig = -110; 2922 else if (sig > -40) /* perfect */ 2923 sig = -40; 2924 /* will give a range of 0 .. 70 */ 2925 iwe.u.qual.qual = sig + 110; 2926 break; 2927 case CFG80211_SIGNAL_TYPE_UNSPEC: 2928 iwe.u.qual.level = bss->pub.signal; 2929 /* will give range 0 .. 100 */ 2930 iwe.u.qual.qual = bss->pub.signal; 2931 break; 2932 default: 2933 /* not reached */ 2934 break; 2935 } 2936 current_ev = iwe_stream_add_event_check(info, current_ev, 2937 end_buf, &iwe, 2938 IW_EV_QUAL_LEN); 2939 if (IS_ERR(current_ev)) 2940 return current_ev; 2941 } 2942 2943 memset(&iwe, 0, sizeof(iwe)); 2944 iwe.cmd = SIOCGIWENCODE; 2945 if (bss->pub.capability & WLAN_CAPABILITY_PRIVACY) 2946 iwe.u.data.flags = IW_ENCODE_ENABLED | IW_ENCODE_NOKEY; 2947 else 2948 iwe.u.data.flags = IW_ENCODE_DISABLED; 2949 iwe.u.data.length = 0; 2950 current_ev = iwe_stream_add_point_check(info, current_ev, end_buf, 2951 &iwe, ""); 2952 if (IS_ERR(current_ev)) 2953 return current_ev; 2954 2955 rcu_read_lock(); 2956 ies = rcu_dereference(bss->pub.ies); 2957 rem = ies->len; 2958 ie = ies->data; 2959 2960 while (rem >= 2) { 2961 /* invalid data */ 2962 if (ie[1] > rem - 2) 2963 break; 2964 2965 switch (ie[0]) { 2966 case WLAN_EID_SSID: 2967 memset(&iwe, 0, sizeof(iwe)); 2968 iwe.cmd = SIOCGIWESSID; 2969 iwe.u.data.length = ie[1]; 2970 iwe.u.data.flags = 1; 2971 current_ev = iwe_stream_add_point_check(info, 2972 current_ev, 2973 end_buf, &iwe, 2974 (u8 *)ie + 2); 2975 if (IS_ERR(current_ev)) 2976 goto unlock; 2977 break; 2978 case WLAN_EID_MESH_ID: 2979 memset(&iwe, 0, sizeof(iwe)); 2980 iwe.cmd = SIOCGIWESSID; 2981 iwe.u.data.length = ie[1]; 2982 iwe.u.data.flags = 1; 2983 current_ev = iwe_stream_add_point_check(info, 2984 current_ev, 2985 end_buf, &iwe, 2986 (u8 *)ie + 2); 2987 if (IS_ERR(current_ev)) 2988 goto unlock; 2989 break; 2990 case WLAN_EID_MESH_CONFIG: 2991 ismesh = true; 2992 if (ie[1] != sizeof(struct ieee80211_meshconf_ie)) 2993 break; 2994 cfg = (u8 *)ie + 2; 2995 memset(&iwe, 0, sizeof(iwe)); 2996 iwe.cmd = IWEVCUSTOM; 2997 sprintf(buf, "Mesh Network Path Selection Protocol ID: " 2998 "0x%02X", cfg[0]); 2999 iwe.u.data.length = strlen(buf); 3000 current_ev = iwe_stream_add_point_check(info, 3001 current_ev, 3002 end_buf, 3003 &iwe, buf); 3004 if (IS_ERR(current_ev)) 3005 goto unlock; 3006 sprintf(buf, "Path Selection Metric ID: 0x%02X", 3007 cfg[1]); 3008 iwe.u.data.length = strlen(buf); 3009 current_ev = iwe_stream_add_point_check(info, 3010 current_ev, 3011 end_buf, 3012 &iwe, buf); 3013 if (IS_ERR(current_ev)) 3014 goto unlock; 3015 sprintf(buf, "Congestion Control Mode ID: 0x%02X", 3016 cfg[2]); 3017 iwe.u.data.length = strlen(buf); 3018 current_ev = iwe_stream_add_point_check(info, 3019 current_ev, 3020 end_buf, 3021 &iwe, buf); 3022 if (IS_ERR(current_ev)) 3023 goto unlock; 3024 sprintf(buf, "Synchronization ID: 0x%02X", cfg[3]); 3025 iwe.u.data.length = strlen(buf); 3026 current_ev = iwe_stream_add_point_check(info, 3027 current_ev, 3028 end_buf, 3029 &iwe, buf); 3030 if (IS_ERR(current_ev)) 3031 goto unlock; 3032 sprintf(buf, "Authentication ID: 0x%02X", cfg[4]); 3033 iwe.u.data.length = strlen(buf); 3034 current_ev = iwe_stream_add_point_check(info, 3035 current_ev, 3036 end_buf, 3037 &iwe, buf); 3038 if (IS_ERR(current_ev)) 3039 goto unlock; 3040 sprintf(buf, "Formation Info: 0x%02X", cfg[5]); 3041 iwe.u.data.length = strlen(buf); 3042 current_ev = iwe_stream_add_point_check(info, 3043 current_ev, 3044 end_buf, 3045 &iwe, buf); 3046 if (IS_ERR(current_ev)) 3047 goto unlock; 3048 sprintf(buf, "Capabilities: 0x%02X", cfg[6]); 3049 iwe.u.data.length = strlen(buf); 3050 current_ev = iwe_stream_add_point_check(info, 3051 current_ev, 3052 end_buf, 3053 &iwe, buf); 3054 if (IS_ERR(current_ev)) 3055 goto unlock; 3056 break; 3057 case WLAN_EID_SUPP_RATES: 3058 case WLAN_EID_EXT_SUPP_RATES: 3059 /* display all supported rates in readable format */ 3060 p = current_ev + iwe_stream_lcp_len(info); 3061 3062 memset(&iwe, 0, sizeof(iwe)); 3063 iwe.cmd = SIOCGIWRATE; 3064 /* Those two flags are ignored... */ 3065 iwe.u.bitrate.fixed = iwe.u.bitrate.disabled = 0; 3066 3067 for (i = 0; i < ie[1]; i++) { 3068 iwe.u.bitrate.value = 3069 ((ie[i + 2] & 0x7f) * 500000); 3070 tmp = p; 3071 p = iwe_stream_add_value(info, current_ev, p, 3072 end_buf, &iwe, 3073 IW_EV_PARAM_LEN); 3074 if (p == tmp) { 3075 current_ev = ERR_PTR(-E2BIG); 3076 goto unlock; 3077 } 3078 } 3079 current_ev = p; 3080 break; 3081 } 3082 rem -= ie[1] + 2; 3083 ie += ie[1] + 2; 3084 } 3085 3086 if (bss->pub.capability & (WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS) || 3087 ismesh) { 3088 memset(&iwe, 0, sizeof(iwe)); 3089 iwe.cmd = SIOCGIWMODE; 3090 if (ismesh) 3091 iwe.u.mode = IW_MODE_MESH; 3092 else if (bss->pub.capability & WLAN_CAPABILITY_ESS) 3093 iwe.u.mode = IW_MODE_MASTER; 3094 else 3095 iwe.u.mode = IW_MODE_ADHOC; 3096 current_ev = iwe_stream_add_event_check(info, current_ev, 3097 end_buf, &iwe, 3098 IW_EV_UINT_LEN); 3099 if (IS_ERR(current_ev)) 3100 goto unlock; 3101 } 3102 3103 memset(&iwe, 0, sizeof(iwe)); 3104 iwe.cmd = IWEVCUSTOM; 3105 sprintf(buf, "tsf=%016llx", (unsigned long long)(ies->tsf)); 3106 iwe.u.data.length = strlen(buf); 3107 current_ev = iwe_stream_add_point_check(info, current_ev, end_buf, 3108 &iwe, buf); 3109 if (IS_ERR(current_ev)) 3110 goto unlock; 3111 memset(&iwe, 0, sizeof(iwe)); 3112 iwe.cmd = IWEVCUSTOM; 3113 sprintf(buf, " Last beacon: %ums ago", 3114 elapsed_jiffies_msecs(bss->ts)); 3115 iwe.u.data.length = strlen(buf); 3116 current_ev = iwe_stream_add_point_check(info, current_ev, 3117 end_buf, &iwe, buf); 3118 if (IS_ERR(current_ev)) 3119 goto unlock; 3120 3121 current_ev = ieee80211_scan_add_ies(info, ies, current_ev, end_buf); 3122 3123 unlock: 3124 rcu_read_unlock(); 3125 return current_ev; 3126 } 3127 3128 3129 static int ieee80211_scan_results(struct cfg80211_registered_device *rdev, 3130 struct iw_request_info *info, 3131 char *buf, size_t len) 3132 { 3133 char *current_ev = buf; 3134 char *end_buf = buf + len; 3135 struct cfg80211_internal_bss *bss; 3136 int err = 0; 3137 3138 spin_lock_bh(&rdev->bss_lock); 3139 cfg80211_bss_expire(rdev); 3140 3141 list_for_each_entry(bss, &rdev->bss_list, list) { 3142 if (buf + len - current_ev <= IW_EV_ADDR_LEN) { 3143 err = -E2BIG; 3144 break; 3145 } 3146 current_ev = ieee80211_bss(&rdev->wiphy, info, bss, 3147 current_ev, end_buf); 3148 if (IS_ERR(current_ev)) { 3149 err = PTR_ERR(current_ev); 3150 break; 3151 } 3152 } 3153 spin_unlock_bh(&rdev->bss_lock); 3154 3155 if (err) 3156 return err; 3157 return current_ev - buf; 3158 } 3159 3160 3161 int cfg80211_wext_giwscan(struct net_device *dev, 3162 struct iw_request_info *info, 3163 struct iw_point *data, char *extra) 3164 { 3165 struct cfg80211_registered_device *rdev; 3166 int res; 3167 3168 if (!netif_running(dev)) 3169 return -ENETDOWN; 3170 3171 rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex); 3172 3173 if (IS_ERR(rdev)) 3174 return PTR_ERR(rdev); 3175 3176 if (rdev->scan_req || rdev->scan_msg) 3177 return -EAGAIN; 3178 3179 res = ieee80211_scan_results(rdev, info, extra, data->length); 3180 data->length = 0; 3181 if (res >= 0) { 3182 data->length = res; 3183 res = 0; 3184 } 3185 3186 return res; 3187 } 3188 EXPORT_WEXT_HANDLER(cfg80211_wext_giwscan); 3189 #endif 3190