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