net/wireless/reg.c

   1 /*
   2  * Copyright 2002-2005, Instant802 Networks, Inc.
   3  * Copyright 2005-2006, Devicescape Software, Inc.
   4  * Copyright 2007       Johannes Berg <johannes@sipsolutions.net>
   5  * Copyright 2008-2011  Luis R. Rodriguez <mcgrof@qca.qualcomm.com>
   6  *
   7  * Permission to use, copy, modify, and/or distribute this software for any
   8  * purpose with or without fee is hereby granted, provided that the above
   9  * copyright notice and this permission notice appear in all copies.
  10  *
  11  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  12  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  13  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  14  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  15  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  16  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  17  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  18  */
  19
  20
  21 /**
  22  * DOC: Wireless regulatory infrastructure
  23  *
  24  * The usual implementation is for a driver to read a device EEPROM to
  25  * determine which regulatory domain it should be operating under, then
  26  * looking up the allowable channels in a driver-local table and finally
  27  * registering those channels in the wiphy structure.
  28  *
  29  * Another set of compliance enforcement is for drivers to use their
  30  * own compliance limits which can be stored on the EEPROM. The host
  31  * driver or firmware may ensure these are used.
  32  *
  33  * In addition to all this we provide an extra layer of regulatory
  34  * conformance. For drivers which do not have any regulatory
  35  * information CRDA provides the complete regulatory solution.
  36  * For others it provides a community effort on further restrictions
  37  * to enhance compliance.
  38  *
  39  * Note: When number of rules --> infinity we will not be able to
  40  * index on alpha2 any more, instead we'll probably have to
  41  * rely on some SHA1 checksum of the regdomain for example.
  42  *
  43  */
  44
  45 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  46
  47 #include <linux/kernel.h>
  48 #include <linux/export.h>
  49 #include <linux/slab.h>
  50 #include <linux/list.h>
  51 #include <linux/ctype.h>
  52 #include <linux/nl80211.h>
  53 #include <linux/platform_device.h>
  54 #include <linux/moduleparam.h>
  55 #include <net/cfg80211.h>
  56 #include "core.h"
  57 #include "reg.h"
  58 #include "regdb.h"
  59 #include "nl80211.h"
  60
  61 #ifdef CONFIG_CFG80211_REG_DEBUG
  62 #define REG_DBG_PRINT(format, args...)                  \
  63         printk(KERN_DEBUG pr_fmt(format), ##args)
  64 #else
  65 #define REG_DBG_PRINT(args...)
  66 #endif
  67
  68 enum reg_request_treatment {
  69         REG_REQ_OK,
  70         REG_REQ_IGNORE,
  71         REG_REQ_INTERSECT,
  72         REG_REQ_ALREADY_SET,
  73 };
  74
  75 static struct regulatory_request core_request_world = {
  76         .initiator = NL80211_REGDOM_SET_BY_CORE,
  77         .alpha2[0] = '0',
  78         .alpha2[1] = '0',
  79         .intersect = false,
  80         .processed = true,
  81         .country_ie_env = ENVIRON_ANY,
  82 };
  83
  84 /*
  85  * Receipt of information from last regulatory request,
  86  * protected by RTNL (and can be accessed with RCU protection)
  87  */
  88 static struct regulatory_request __rcu *last_request =
  89         (void __rcu *)&core_request_world;
  90
  91 /* To trigger userspace events */
  92 static struct platform_device *reg_pdev;
  93
  94 static struct device_type reg_device_type = {
  95         .uevent = reg_device_uevent,
  96 };
  97
  98 /*
  99  * Central wireless core regulatory domains, we only need two,
 100  * the current one and a world regulatory domain in case we have no
 101  * information to give us an alpha2.
 102  * (protected by RTNL, can be read under RCU)
 103  */
 104 const struct ieee80211_regdomain __rcu *cfg80211_regdomain;
 105
 106 /*
 107  * Number of devices that registered to the core
 108  * that support cellular base station regulatory hints
 109  * (protected by RTNL)
 110  */
 111 static int reg_num_devs_support_basehint;
 112
 113 static const struct ieee80211_regdomain *get_cfg80211_regdom(void)
 114 {
 115         return rtnl_dereference(cfg80211_regdomain);
 116 }
 117
 118 static const struct ieee80211_regdomain *get_wiphy_regdom(struct wiphy *wiphy)
 119 {
 120         return rtnl_dereference(wiphy->regd);
 121 }
 122
 123 static const char *reg_dfs_region_str(enum nl80211_dfs_regions dfs_region)
 124 {
 125         switch (dfs_region) {
 126         case NL80211_DFS_UNSET:
 127                 return "unset";
 128         case NL80211_DFS_FCC:
 129                 return "FCC";
 130         case NL80211_DFS_ETSI:
 131                 return "ETSI";
 132         case NL80211_DFS_JP:
 133                 return "JP";
 134         }
 135         return "Unknown";
 136 }
 137
 138 static void rcu_free_regdom(const struct ieee80211_regdomain *r)
 139 {
 140         if (!r)
 141                 return;
 142         kfree_rcu((struct ieee80211_regdomain *)r, rcu_head);
 143 }
 144
 145 static struct regulatory_request *get_last_request(void)
 146 {
 147         return rcu_dereference_rtnl(last_request);
 148 }
 149
 150 /* Used to queue up regulatory hints */
 151 static LIST_HEAD(reg_requests_list);
 152 static spinlock_t reg_requests_lock;
 153
 154 /* Used to queue up beacon hints for review */
 155 static LIST_HEAD(reg_pending_beacons);
 156 static spinlock_t reg_pending_beacons_lock;
 157
 158 /* Used to keep track of processed beacon hints */
 159 static LIST_HEAD(reg_beacon_list);
 160
 161 struct reg_beacon {
 162         struct list_head list;
 163         struct ieee80211_channel chan;
 164 };
 165
 166 static void reg_todo(struct work_struct *work);
 167 static DECLARE_WORK(reg_work, reg_todo);
 168
 169 static void reg_timeout_work(struct work_struct *work);
 170 static DECLARE_DELAYED_WORK(reg_timeout, reg_timeout_work);
 171
 172 /* We keep a static world regulatory domain in case of the absence of CRDA */
 173 static const struct ieee80211_regdomain world_regdom = {
 174         .n_reg_rules = 6,
 175         .alpha2 =  "00",
 176         .reg_rules = {
 177                 /* IEEE 802.11b/g, channels 1..11 */
 178                 REG_RULE(2412-10, 2462+10, 40, 6, 20, 0),
 179                 /* IEEE 802.11b/g, channels 12..13. */
 180                 REG_RULE(2467-10, 2472+10, 40, 6, 20,
 181                         NL80211_RRF_NO_IR),
 182                 /* IEEE 802.11 channel 14 - Only JP enables
 183                  * this and for 802.11b only */
 184                 REG_RULE(2484-10, 2484+10, 20, 6, 20,
 185                         NL80211_RRF_NO_IR |
 186                         NL80211_RRF_NO_OFDM),
 187                 /* IEEE 802.11a, channel 36..48 */
 188                 REG_RULE(5180-10, 5240+10, 160, 6, 20,
 189                         NL80211_RRF_NO_IR),
 190
 191                 /* IEEE 802.11a, channel 52..64 - DFS required */
 192                 REG_RULE(5260-10, 5320+10, 160, 6, 20,
 193                         NL80211_RRF_NO_IR |
 194                         NL80211_RRF_DFS),
 195
 196                 /* IEEE 802.11a, channel 100..144 - DFS required */
 197                 REG_RULE(5500-10, 5720+10, 160, 6, 20,
 198                         NL80211_RRF_NO_IR |
 199                         NL80211_RRF_DFS),
 200
 201                 /* IEEE 802.11a, channel 149..165 */
 202                 REG_RULE(5745-10, 5825+10, 80, 6, 20,
 203                         NL80211_RRF_NO_IR),
 204
 205                 /* IEEE 802.11ad (60gHz), channels 1..3 */
 206                 REG_RULE(56160+2160*1-1080, 56160+2160*3+1080, 2160, 0, 0, 0),
 207         }
 208 };
 209
 210 /* protected by RTNL */
 211 static const struct ieee80211_regdomain *cfg80211_world_regdom =
 212         &world_regdom;
 213
 214 static char *ieee80211_regdom = "00";
 215 static char user_alpha2[2];
 216
 217 module_param(ieee80211_regdom, charp, 0444);
 218 MODULE_PARM_DESC(ieee80211_regdom, "IEEE 802.11 regulatory domain code");
 219
 220 static void reg_kfree_last_request(void)
 221 {
 222         struct regulatory_request *lr;
 223
 224         lr = get_last_request();
 225
 226         if (lr != &core_request_world && lr)
 227                 kfree_rcu(lr, rcu_head);
 228 }
 229
 230 static void reg_update_last_request(struct regulatory_request *request)
 231 {
 232         reg_kfree_last_request();
 233         rcu_assign_pointer(last_request, request);
 234 }
 235
 236 static void reset_regdomains(bool full_reset,
 237                              const struct ieee80211_regdomain *new_regdom)
 238 {
 239         const struct ieee80211_regdomain *r;
 240
 241         ASSERT_RTNL();
 242
 243         r = get_cfg80211_regdom();
 244
 245         /* avoid freeing static information or freeing something twice */
 246         if (r == cfg80211_world_regdom)
 247                 r = NULL;
 248         if (cfg80211_world_regdom == &world_regdom)
 249                 cfg80211_world_regdom = NULL;
 250         if (r == &world_regdom)
 251                 r = NULL;
 252
 253         rcu_free_regdom(r);
 254         rcu_free_regdom(cfg80211_world_regdom);
 255
 256         cfg80211_world_regdom = &world_regdom;
 257         rcu_assign_pointer(cfg80211_regdomain, new_regdom);
 258
 259         if (!full_reset)
 260                 return;
 261
 262         reg_update_last_request(&core_request_world);
 263 }
 264
 265 /*
 266  * Dynamic world regulatory domain requested by the wireless
 267  * core upon initialization
 268  */
 269 static void update_world_regdomain(const struct ieee80211_regdomain *rd)
 270 {
 271         struct regulatory_request *lr;
 272
 273         lr = get_last_request();
 274
 275         WARN_ON(!lr);
 276
 277         reset_regdomains(false, rd);
 278
 279         cfg80211_world_regdom = rd;
 280 }
 281
 282 bool is_world_regdom(const char *alpha2)
 283 {
 284         if (!alpha2)
 285                 return false;
 286         return alpha2[0] == '0' && alpha2[1] == '0';
 287 }
 288
 289 static bool is_alpha2_set(const char *alpha2)
 290 {
 291         if (!alpha2)
 292                 return false;
 293         return alpha2[0] && alpha2[1];
 294 }
 295
 296 static bool is_unknown_alpha2(const char *alpha2)
 297 {
 298         if (!alpha2)
 299                 return false;
 300         /*
 301          * Special case where regulatory domain was built by driver
 302          * but a specific alpha2 cannot be determined
 303          */
 304         return alpha2[0] == '9' && alpha2[1] == '9';
 305 }
 306
 307 static bool is_intersected_alpha2(const char *alpha2)
 308 {
 309         if (!alpha2)
 310                 return false;
 311         /*
 312          * Special case where regulatory domain is the
 313          * result of an intersection between two regulatory domain
 314          * structures
 315          */
 316         return alpha2[0] == '9' && alpha2[1] == '8';
 317 }
 318
 319 static bool is_an_alpha2(const char *alpha2)
 320 {
 321         if (!alpha2)
 322                 return false;
 323         return isalpha(alpha2[0]) && isalpha(alpha2[1]);
 324 }
 325
 326 static bool alpha2_equal(const char *alpha2_x, const char *alpha2_y)
 327 {
 328         if (!alpha2_x || !alpha2_y)
 329                 return false;
 330         return alpha2_x[0] == alpha2_y[0] && alpha2_x[1] == alpha2_y[1];
 331 }
 332
 333 static bool regdom_changes(const char *alpha2)
 334 {
 335         const struct ieee80211_regdomain *r = get_cfg80211_regdom();
 336
 337         if (!r)
 338                 return true;
 339         return !alpha2_equal(r->alpha2, alpha2);
 340 }
 341
 342 /*
 343  * The NL80211_REGDOM_SET_BY_USER regdom alpha2 is cached, this lets
 344  * you know if a valid regulatory hint with NL80211_REGDOM_SET_BY_USER
 345  * has ever been issued.
 346  */
 347 static bool is_user_regdom_saved(void)
 348 {
 349         if (user_alpha2[0] == '9' && user_alpha2[1] == '7')
 350                 return false;
 351
 352         /* This would indicate a mistake on the design */
 353         if (WARN(!is_world_regdom(user_alpha2) && !is_an_alpha2(user_alpha2),
 354                  "Unexpected user alpha2: %c%c\n",
 355                  user_alpha2[0], user_alpha2[1]))
 356                 return false;
 357
 358         return true;
 359 }
 360
 361 static const struct ieee80211_regdomain *
 362 reg_copy_regd(const struct ieee80211_regdomain *src_regd)
 363 {
 364         struct ieee80211_regdomain *regd;
 365         int size_of_regd;
 366         unsigned int i;
 367
 368         size_of_regd =
 369                 sizeof(struct ieee80211_regdomain) +
 370                 src_regd->n_reg_rules * sizeof(struct ieee80211_reg_rule);
 371
 372         regd = kzalloc(size_of_regd, GFP_KERNEL);
 373         if (!regd)
 374                 return ERR_PTR(-ENOMEM);
 375
 376         memcpy(regd, src_regd, sizeof(struct ieee80211_regdomain));
 377
 378         for (i = 0; i < src_regd->n_reg_rules; i++)
 379                 memcpy(&regd->reg_rules[i], &src_regd->reg_rules[i],
 380                        sizeof(struct ieee80211_reg_rule));
 381
 382         return regd;
 383 }
 384
 385 #ifdef CONFIG_CFG80211_INTERNAL_REGDB
 386 struct reg_regdb_search_request {
 387         char alpha2[2];
 388         struct list_head list;
 389 };
 390
 391 static LIST_HEAD(reg_regdb_search_list);
 392 static DEFINE_MUTEX(reg_regdb_search_mutex);
 393
 394 static void reg_regdb_search(struct work_struct *work)
 395 {
 396         struct reg_regdb_search_request *request;
 397         const struct ieee80211_regdomain *curdom, *regdom = NULL;
 398         int i;
 399
 400         rtnl_lock();
 401
 402         mutex_lock(&reg_regdb_search_mutex);
 403         while (!list_empty(&reg_regdb_search_list)) {
 404                 request = list_first_entry(&reg_regdb_search_list,
 405                                            struct reg_regdb_search_request,
 406                                            list);
 407                 list_del(&request->list);
 408
 409                 for (i = 0; i < reg_regdb_size; i++) {
 410                         curdom = reg_regdb[i];
 411
 412                         if (alpha2_equal(request->alpha2, curdom->alpha2)) {
 413                                 regdom = reg_copy_regd(curdom);
 414                                 break;
 415                         }
 416                 }
 417
 418                 kfree(request);
 419         }
 420         mutex_unlock(&reg_regdb_search_mutex);
 421
 422         if (!IS_ERR_OR_NULL(regdom))
 423                 set_regdom(regdom);
 424
 425         rtnl_unlock();
 426 }
 427
 428 static DECLARE_WORK(reg_regdb_work, reg_regdb_search);
 429
 430 static void reg_regdb_query(const char *alpha2)
 431 {
 432         struct reg_regdb_search_request *request;
 433
 434         if (!alpha2)
 435                 return;
 436
 437         request = kzalloc(sizeof(struct reg_regdb_search_request), GFP_KERNEL);
 438         if (!request)
 439                 return;
 440
 441         memcpy(request->alpha2, alpha2, 2);
 442
 443         mutex_lock(&reg_regdb_search_mutex);
 444         list_add_tail(&request->list, &reg_regdb_search_list);
 445         mutex_unlock(&reg_regdb_search_mutex);
 446
 447         schedule_work(&reg_regdb_work);
 448 }
 449
 450 /* Feel free to add any other sanity checks here */
 451 static void reg_regdb_size_check(void)
 452 {
 453         /* We should ideally BUILD_BUG_ON() but then random builds would fail */
 454         WARN_ONCE(!reg_regdb_size, "db.txt is empty, you should update it...");
 455 }
 456 #else
 457 static inline void reg_regdb_size_check(void) {}
 458 static inline void reg_regdb_query(const char *alpha2) {}
 459 #endif /* CONFIG_CFG80211_INTERNAL_REGDB */
 460
 461 /*
 462  * This lets us keep regulatory code which is updated on a regulatory
 463  * basis in userspace. Country information is filled in by
 464  * reg_device_uevent
 465  */
 466 static int call_crda(const char *alpha2)
 467 {
 468         if (!is_world_regdom((char *) alpha2))
 469                 pr_info("Calling CRDA for country: %c%c\n",
 470                         alpha2[0], alpha2[1]);
 471         else
 472                 pr_info("Calling CRDA to update world regulatory domain\n");
 473
 474         /* query internal regulatory database (if it exists) */
 475         reg_regdb_query(alpha2);
 476
 477         return kobject_uevent(&reg_pdev->dev.kobj, KOBJ_CHANGE);
 478 }
 479
 480 static enum reg_request_treatment
 481 reg_call_crda(struct regulatory_request *request)
 482 {
 483         if (call_crda(request->alpha2))
 484                 return REG_REQ_IGNORE;
 485         return REG_REQ_OK;
 486 }
 487
 488 bool reg_is_valid_request(const char *alpha2)
 489 {
 490         struct regulatory_request *lr = get_last_request();
 491
 492         if (!lr || lr->processed)
 493                 return false;
 494
 495         return alpha2_equal(lr->alpha2, alpha2);
 496 }
 497
 498 /* Sanity check on a regulatory rule */
 499 static bool is_valid_reg_rule(const struct ieee80211_reg_rule *rule)
 500 {
 501         const struct ieee80211_freq_range *freq_range = &rule->freq_range;
 502         u32 freq_diff;
 503
 504         if (freq_range->start_freq_khz <= 0 || freq_range->end_freq_khz <= 0)
 505                 return false;
 506
 507         if (freq_range->start_freq_khz > freq_range->end_freq_khz)
 508                 return false;
 509
 510         freq_diff = freq_range->end_freq_khz - freq_range->start_freq_khz;
 511
 512         if (freq_range->end_freq_khz <= freq_range->start_freq_khz ||
 513             freq_range->max_bandwidth_khz > freq_diff)
 514                 return false;
 515
 516         return true;
 517 }
 518
 519 static bool is_valid_rd(const struct ieee80211_regdomain *rd)
 520 {
 521         const struct ieee80211_reg_rule *reg_rule = NULL;
 522         unsigned int i;
 523
 524         if (!rd->n_reg_rules)
 525                 return false;
 526
 527         if (WARN_ON(rd->n_reg_rules > NL80211_MAX_SUPP_REG_RULES))
 528                 return false;
 529
 530         for (i = 0; i < rd->n_reg_rules; i++) {
 531                 reg_rule = &rd->reg_rules[i];
 532                 if (!is_valid_reg_rule(reg_rule))
 533                         return false;
 534         }
 535
 536         return true;
 537 }
 538
 539 static bool reg_does_bw_fit(const struct ieee80211_freq_range *freq_range,
 540                             u32 center_freq_khz, u32 bw_khz)
 541 {
 542         u32 start_freq_khz, end_freq_khz;
 543
 544         start_freq_khz = center_freq_khz - (bw_khz/2);
 545         end_freq_khz = center_freq_khz + (bw_khz/2);
 546
 547         if (start_freq_khz >= freq_range->start_freq_khz &&
 548             end_freq_khz <= freq_range->end_freq_khz)
 549                 return true;
 550
 551         return false;
 552 }
 553
 554 /**
 555  * freq_in_rule_band - tells us if a frequency is in a frequency band
 556  * @freq_range: frequency rule we want to query
 557  * @freq_khz: frequency we are inquiring about
 558  *
 559  * This lets us know if a specific frequency rule is or is not relevant to
 560  * a specific frequency's band. Bands are device specific and artificial
 561  * definitions (the "2.4 GHz band", the "5 GHz band" and the "60GHz band"),
 562  * however it is safe for now to assume that a frequency rule should not be
 563  * part of a frequency's band if the start freq or end freq are off by more
 564  * than 2 GHz for the 2.4 and 5 GHz bands, and by more than 10 GHz for the
 565  * 60 GHz band.
 566  * This resolution can be lowered and should be considered as we add
 567  * regulatory rule support for other "bands".
 568  **/
 569 static bool freq_in_rule_band(const struct ieee80211_freq_range *freq_range,
 570                               u32 freq_khz)
 571 {
 572 #define ONE_GHZ_IN_KHZ  1000000
 573         /*
 574          * From 802.11ad: directional multi-gigabit (DMG):
 575          * Pertaining to operation in a frequency band containing a channel
 576          * with the Channel starting frequency above 45 GHz.
 577          */
 578         u32 limit = freq_khz > 45 * ONE_GHZ_IN_KHZ ?
 579                         10 * ONE_GHZ_IN_KHZ : 2 * ONE_GHZ_IN_KHZ;
 580         if (abs(freq_khz - freq_range->start_freq_khz) <= limit)
 581                 return true;
 582         if (abs(freq_khz - freq_range->end_freq_khz) <= limit)
 583                 return true;
 584         return false;
 585 #undef ONE_GHZ_IN_KHZ
 586 }
 587
 588 /*
 589  * Later on we can perhaps use the more restrictive DFS
 590  * region but we don't have information for that yet so
 591  * for now simply disallow conflicts.
 592  */
 593 static enum nl80211_dfs_regions
 594 reg_intersect_dfs_region(const enum nl80211_dfs_regions dfs_region1,
 595                          const enum nl80211_dfs_regions dfs_region2)
 596 {
 597         if (dfs_region1 != dfs_region2)
 598                 return NL80211_DFS_UNSET;
 599         return dfs_region1;
 600 }
 601
 602 /*
 603  * Helper for regdom_intersect(), this does the real
 604  * mathematical intersection fun
 605  */
 606 static int reg_rules_intersect(const struct ieee80211_reg_rule *rule1,
 607                                const struct ieee80211_reg_rule *rule2,
 608                                struct ieee80211_reg_rule *intersected_rule)
 609 {
 610         const struct ieee80211_freq_range *freq_range1, *freq_range2;
 611         struct ieee80211_freq_range *freq_range;
 612         const struct ieee80211_power_rule *power_rule1, *power_rule2;
 613         struct ieee80211_power_rule *power_rule;
 614         u32 freq_diff;
 615
 616         freq_range1 = &rule1->freq_range;
 617         freq_range2 = &rule2->freq_range;
 618         freq_range = &intersected_rule->freq_range;
 619
 620         power_rule1 = &rule1->power_rule;
 621         power_rule2 = &rule2->power_rule;
 622         power_rule = &intersected_rule->power_rule;
 623
 624         freq_range->start_freq_khz = max(freq_range1->start_freq_khz,
 625                                          freq_range2->start_freq_khz);
 626         freq_range->end_freq_khz = min(freq_range1->end_freq_khz,
 627                                        freq_range2->end_freq_khz);
 628         freq_range->max_bandwidth_khz = min(freq_range1->max_bandwidth_khz,
 629                                             freq_range2->max_bandwidth_khz);
 630
 631         freq_diff = freq_range->end_freq_khz - freq_range->start_freq_khz;
 632         if (freq_range->max_bandwidth_khz > freq_diff)
 633                 freq_range->max_bandwidth_khz = freq_diff;
 634
 635         power_rule->max_eirp = min(power_rule1->max_eirp,
 636                 power_rule2->max_eirp);
 637         power_rule->max_antenna_gain = min(power_rule1->max_antenna_gain,
 638                 power_rule2->max_antenna_gain);
 639
 640         intersected_rule->flags = rule1->flags | rule2->flags;
 641
 642         if (!is_valid_reg_rule(intersected_rule))
 643                 return -EINVAL;
 644
 645         return 0;
 646 }
 647
 648 /**
 649  * regdom_intersect - do the intersection between two regulatory domains
 650  * @rd1: first regulatory domain
 651  * @rd2: second regulatory domain
 652  *
 653  * Use this function to get the intersection between two regulatory domains.
 654  * Once completed we will mark the alpha2 for the rd as intersected, "98",
 655  * as no one single alpha2 can represent this regulatory domain.
 656  *
 657  * Returns a pointer to the regulatory domain structure which will hold the
 658  * resulting intersection of rules between rd1 and rd2. We will
 659  * kzalloc() this structure for you.
 660  */
 661 static struct ieee80211_regdomain *
 662 regdom_intersect(const struct ieee80211_regdomain *rd1,
 663                  const struct ieee80211_regdomain *rd2)
 664 {
 665         int r, size_of_regd;
 666         unsigned int x, y;
 667         unsigned int num_rules = 0, rule_idx = 0;
 668         const struct ieee80211_reg_rule *rule1, *rule2;
 669         struct ieee80211_reg_rule *intersected_rule;
 670         struct ieee80211_regdomain *rd;
 671         /* This is just a dummy holder to help us count */
 672         struct ieee80211_reg_rule dummy_rule;
 673
 674         if (!rd1 || !rd2)
 675                 return NULL;
 676
 677         /*
 678          * First we get a count of the rules we'll need, then we actually
 679          * build them. This is to so we can malloc() and free() a
 680          * regdomain once. The reason we use reg_rules_intersect() here
 681          * is it will return -EINVAL if the rule computed makes no sense.
 682          * All rules that do check out OK are valid.
 683          */
 684
 685         for (x = 0; x < rd1->n_reg_rules; x++) {
 686                 rule1 = &rd1->reg_rules[x];
 687                 for (y = 0; y < rd2->n_reg_rules; y++) {
 688                         rule2 = &rd2->reg_rules[y];
 689                         if (!reg_rules_intersect(rule1, rule2, &dummy_rule))
 690                                 num_rules++;
 691                 }
 692         }
 693
 694         if (!num_rules)
 695                 return NULL;
 696
 697         size_of_regd = sizeof(struct ieee80211_regdomain) +
 698                        num_rules * sizeof(struct ieee80211_reg_rule);
 699
 700         rd = kzalloc(size_of_regd, GFP_KERNEL);
 701         if (!rd)
 702                 return NULL;
 703
 704         for (x = 0; x < rd1->n_reg_rules && rule_idx < num_rules; x++) {
 705                 rule1 = &rd1->reg_rules[x];
 706                 for (y = 0; y < rd2->n_reg_rules && rule_idx < num_rules; y++) {
 707                         rule2 = &rd2->reg_rules[y];
 708                         /*
 709                          * This time around instead of using the stack lets
 710                          * write to the target rule directly saving ourselves
 711                          * a memcpy()
 712                          */
 713                         intersected_rule = &rd->reg_rules[rule_idx];
 714                         r = reg_rules_intersect(rule1, rule2, intersected_rule);
 715                         /*
 716                          * No need to memset here the intersected rule here as
 717                          * we're not using the stack anymore
 718                          */
 719                         if (r)
 720                                 continue;
 721                         rule_idx++;
 722                 }
 723         }
 724
 725         if (rule_idx != num_rules) {
 726                 kfree(rd);
 727                 return NULL;
 728         }
 729
 730         rd->n_reg_rules = num_rules;
 731         rd->alpha2[0] = '9';
 732         rd->alpha2[1] = '8';
 733         rd->dfs_region = reg_intersect_dfs_region(rd1->dfs_region,
 734                                                   rd2->dfs_region);
 735
 736         return rd;
 737 }
 738
 739 /*
 740  * XXX: add support for the rest of enum nl80211_reg_rule_flags, we may
 741  * want to just have the channel structure use these
 742  */
 743 static u32 map_regdom_flags(u32 rd_flags)
 744 {
 745         u32 channel_flags = 0;
 746         if (rd_flags & NL80211_RRF_NO_IR_ALL)
 747                 channel_flags |= IEEE80211_CHAN_NO_IR;
 748         if (rd_flags & NL80211_RRF_DFS)
 749                 channel_flags |= IEEE80211_CHAN_RADAR;
 750         if (rd_flags & NL80211_RRF_NO_OFDM)
 751                 channel_flags |= IEEE80211_CHAN_NO_OFDM;
 752         return channel_flags;
 753 }
 754
 755 static const struct ieee80211_reg_rule *
 756 freq_reg_info_regd(struct wiphy *wiphy, u32 center_freq,
 757                    const struct ieee80211_regdomain *regd)
 758 {
 759         int i;
 760         bool band_rule_found = false;
 761         bool bw_fits = false;
 762
 763         if (!regd)
 764                 return ERR_PTR(-EINVAL);
 765
 766         for (i = 0; i < regd->n_reg_rules; i++) {
 767                 const struct ieee80211_reg_rule *rr;
 768                 const struct ieee80211_freq_range *fr = NULL;
 769
 770                 rr = &regd->reg_rules[i];
 771                 fr = &rr->freq_range;
 772
 773                 /*
 774                  * We only need to know if one frequency rule was
 775                  * was in center_freq's band, that's enough, so lets
 776                  * not overwrite it once found
 777                  */
 778                 if (!band_rule_found)
 779                         band_rule_found = freq_in_rule_band(fr, center_freq);
 780
 781                 bw_fits = reg_does_bw_fit(fr, center_freq, MHZ_TO_KHZ(20));
 782
 783                 if (band_rule_found && bw_fits)
 784                         return rr;
 785         }
 786
 787         if (!band_rule_found)
 788                 return ERR_PTR(-ERANGE);
 789
 790         return ERR_PTR(-EINVAL);
 791 }
 792
 793 const struct ieee80211_reg_rule *freq_reg_info(struct wiphy *wiphy,
 794                                                u32 center_freq)
 795 {
 796         const struct ieee80211_regdomain *regd;
 797         struct regulatory_request *lr = get_last_request();
 798
 799         /*
 800          * Follow the driver's regulatory domain, if present, unless a country
 801          * IE has been processed or a user wants to help complaince further
 802          */
 803         if (lr->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE &&
 804             lr->initiator != NL80211_REGDOM_SET_BY_USER &&
 805             wiphy->regd)
 806                 regd = get_wiphy_regdom(wiphy);
 807         else
 808                 regd = get_cfg80211_regdom();
 809
 810         return freq_reg_info_regd(wiphy, center_freq, regd);
 811 }
 812 EXPORT_SYMBOL(freq_reg_info);
 813
 814 const char *reg_initiator_name(enum nl80211_reg_initiator initiator)
 815 {
 816         switch (initiator) {
 817         case NL80211_REGDOM_SET_BY_CORE:
 818                 return "core";
 819         case NL80211_REGDOM_SET_BY_USER:
 820                 return "user";
 821         case NL80211_REGDOM_SET_BY_DRIVER:
 822                 return "driver";
 823         case NL80211_REGDOM_SET_BY_COUNTRY_IE:
 824                 return "country IE";
 825         default:
 826                 WARN_ON(1);
 827                 return "bug";
 828         }
 829 }
 830 EXPORT_SYMBOL(reg_initiator_name);
 831
 832 #ifdef CONFIG_CFG80211_REG_DEBUG
 833 static void chan_reg_rule_print_dbg(struct ieee80211_channel *chan,
 834                                     const struct ieee80211_reg_rule *reg_rule)
 835 {
 836         const struct ieee80211_power_rule *power_rule;
 837         const struct ieee80211_freq_range *freq_range;
 838         char max_antenna_gain[32];
 839
 840         power_rule = &reg_rule->power_rule;
 841         freq_range = &reg_rule->freq_range;
 842
 843         if (!power_rule->max_antenna_gain)
 844                 snprintf(max_antenna_gain, 32, "N/A");
 845         else
 846                 snprintf(max_antenna_gain, 32, "%d", power_rule->max_antenna_gain);
 847
 848         REG_DBG_PRINT("Updating information on frequency %d MHz with regulatory rule:\n",
 849                       chan->center_freq);
 850
 851         REG_DBG_PRINT("%d KHz - %d KHz @ %d KHz), (%s mBi, %d mBm)\n",
 852                       freq_range->start_freq_khz, freq_range->end_freq_khz,
 853                       freq_range->max_bandwidth_khz, max_antenna_gain,
 854                       power_rule->max_eirp);
 855 }
 856 #else
 857 static void chan_reg_rule_print_dbg(struct ieee80211_channel *chan,
 858                                     const struct ieee80211_reg_rule *reg_rule)
 859 {
 860         return;
 861 }
 862 #endif
 863
 864 /*
 865  * Note that right now we assume the desired channel bandwidth
 866  * is always 20 MHz for each individual channel (HT40 uses 20 MHz
 867  * per channel, the primary and the extension channel).
 868  */
 869 static void handle_channel(struct wiphy *wiphy,
 870                            enum nl80211_reg_initiator initiator,
 871                            struct ieee80211_channel *chan)
 872 {
 873         u32 flags, bw_flags = 0;
 874         const struct ieee80211_reg_rule *reg_rule = NULL;
 875         const struct ieee80211_power_rule *power_rule = NULL;
 876         const struct ieee80211_freq_range *freq_range = NULL;
 877         struct wiphy *request_wiphy = NULL;
 878         struct regulatory_request *lr = get_last_request();
 879
 880         request_wiphy = wiphy_idx_to_wiphy(lr->wiphy_idx);
 881
 882         flags = chan->orig_flags;
 883
 884         reg_rule = freq_reg_info(wiphy, MHZ_TO_KHZ(chan->center_freq));
 885         if (IS_ERR(reg_rule)) {
 886                 /*
 887                  * We will disable all channels that do not match our
 888                  * received regulatory rule unless the hint is coming
 889                  * from a Country IE and the Country IE had no information
 890                  * about a band. The IEEE 802.11 spec allows for an AP
 891                  * to send only a subset of the regulatory rules allowed,
 892                  * so an AP in the US that only supports 2.4 GHz may only send
 893                  * a country IE with information for the 2.4 GHz band
 894                  * while 5 GHz is still supported.
 895                  */
 896                 if (initiator == NL80211_REGDOM_SET_BY_COUNTRY_IE &&
 897                     PTR_ERR(reg_rule) == -ERANGE)
 898                         return;
 899
 900                 if (lr->initiator == NL80211_REGDOM_SET_BY_DRIVER &&
 901                     request_wiphy && request_wiphy == wiphy &&
 902                     request_wiphy->regulatory_flags & REGULATORY_STRICT_REG) {
 903                         REG_DBG_PRINT("Disabling freq %d MHz for good\n",
 904                                       chan->center_freq);
 905                         chan->orig_flags |= IEEE80211_CHAN_DISABLED;
 906                         chan->flags = chan->orig_flags;
 907                 } else {
 908                         REG_DBG_PRINT("Disabling freq %d MHz\n",
 909                                       chan->center_freq);
 910                         chan->flags |= IEEE80211_CHAN_DISABLED;
 911                 }
 912                 return;
 913         }
 914
 915         chan_reg_rule_print_dbg(chan, reg_rule);
 916
 917         power_rule = &reg_rule->power_rule;
 918         freq_range = &reg_rule->freq_range;
 919
 920         if (freq_range->max_bandwidth_khz < MHZ_TO_KHZ(40))
 921                 bw_flags = IEEE80211_CHAN_NO_HT40;
 922         if (freq_range->max_bandwidth_khz < MHZ_TO_KHZ(80))
 923                 bw_flags |= IEEE80211_CHAN_NO_80MHZ;
 924         if (freq_range->max_bandwidth_khz < MHZ_TO_KHZ(160))
 925                 bw_flags |= IEEE80211_CHAN_NO_160MHZ;
 926
 927         if (lr->initiator == NL80211_REGDOM_SET_BY_DRIVER &&
 928             request_wiphy && request_wiphy == wiphy &&
 929             request_wiphy->regulatory_flags & REGULATORY_STRICT_REG) {
 930                 /*
 931                  * This guarantees the driver's requested regulatory domain
 932                  * will always be used as a base for further regulatory
 933                  * settings
 934                  */
 935                 chan->flags = chan->orig_flags =
 936                         map_regdom_flags(reg_rule->flags) | bw_flags;
 937                 chan->max_antenna_gain = chan->orig_mag =
 938                         (int) MBI_TO_DBI(power_rule->max_antenna_gain);
 939                 chan->max_reg_power = chan->max_power = chan->orig_mpwr =
 940                         (int) MBM_TO_DBM(power_rule->max_eirp);
 941                 return;
 942         }
 943
 944         chan->dfs_state = NL80211_DFS_USABLE;
 945         chan->dfs_state_entered = jiffies;
 946
 947         chan->beacon_found = false;
 948         chan->flags = flags | bw_flags | map_regdom_flags(reg_rule->flags);
 949         chan->max_antenna_gain =
 950                 min_t(int, chan->orig_mag,
 951                       MBI_TO_DBI(power_rule->max_antenna_gain));
 952         chan->max_reg_power = (int) MBM_TO_DBM(power_rule->max_eirp);
 953         if (chan->orig_mpwr) {
 954                 /*
 955                  * Devices that use REGULATORY_COUNTRY_IE_FOLLOW_POWER
 956                  * will always follow the passed country IE power settings.
 957                  */
 958                 if (initiator == NL80211_REGDOM_SET_BY_COUNTRY_IE &&
 959                     wiphy->regulatory_flags & REGULATORY_COUNTRY_IE_FOLLOW_POWER)
 960                         chan->max_power = chan->max_reg_power;
 961                 else
 962                         chan->max_power = min(chan->orig_mpwr,
 963                                               chan->max_reg_power);
 964         } else
 965                 chan->max_power = chan->max_reg_power;
 966 }
 967
 968 static void handle_band(struct wiphy *wiphy,
 969                         enum nl80211_reg_initiator initiator,
 970                         struct ieee80211_supported_band *sband)
 971 {
 972         unsigned int i;
 973
 974         if (!sband)
 975                 return;
 976
 977         for (i = 0; i < sband->n_channels; i++)
 978                 handle_channel(wiphy, initiator, &sband->channels[i]);
 979 }
 980
 981 static bool reg_request_cell_base(struct regulatory_request *request)
 982 {
 983         if (request->initiator != NL80211_REGDOM_SET_BY_USER)
 984                 return false;
 985         return request->user_reg_hint_type == NL80211_USER_REG_HINT_CELL_BASE;
 986 }
 987
 988 bool reg_last_request_cell_base(void)
 989 {
 990         return reg_request_cell_base(get_last_request());
 991 }
 992
 993 #ifdef CONFIG_CFG80211_CERTIFICATION_ONUS
 994 /* Core specific check */
 995 static enum reg_request_treatment
 996 reg_ignore_cell_hint(struct regulatory_request *pending_request)
 997 {
 998         struct regulatory_request *lr = get_last_request();
 999
1000         if (!reg_num_devs_support_basehint)
1001                 return REG_REQ_IGNORE;
1002
1003         if (reg_request_cell_base(lr) &&
1004             !regdom_changes(pending_request->alpha2))
1005                 return REG_REQ_ALREADY_SET;
1006
1007         return REG_REQ_OK;
1008 }
1009
1010 /* Device specific check */
1011 static bool reg_dev_ignore_cell_hint(struct wiphy *wiphy)
1012 {
1013         return !(wiphy->features & NL80211_FEATURE_CELL_BASE_REG_HINTS);
1014 }
1015 #else
1016 static int reg_ignore_cell_hint(struct regulatory_request *pending_request)
1017 {
1018         return REG_REQ_IGNORE;
1019 }
1020
1021 static bool reg_dev_ignore_cell_hint(struct wiphy *wiphy)
1022 {
1023         return true;
1024 }
1025 #endif
1026
1027 static bool wiphy_strict_alpha2_regd(struct wiphy *wiphy)
1028 {
1029         if (wiphy->regulatory_flags & REGULATORY_STRICT_REG &&
1030             !(wiphy->regulatory_flags & REGULATORY_CUSTOM_REG))
1031                 return true;
1032         return false;
1033 }
1034
1035 static bool ignore_reg_update(struct wiphy *wiphy,
1036                               enum nl80211_reg_initiator initiator)
1037 {
1038         struct regulatory_request *lr = get_last_request();
1039
1040         if (!lr) {
1041                 REG_DBG_PRINT("Ignoring regulatory request set by %s "
1042                               "since last_request is not set\n",
1043                               reg_initiator_name(initiator));
1044                 return true;
1045         }
1046
1047         if (initiator == NL80211_REGDOM_SET_BY_CORE &&
1048             wiphy->regulatory_flags & REGULATORY_CUSTOM_REG) {
1049                 REG_DBG_PRINT("Ignoring regulatory request set by %s "
1050                               "since the driver uses its own custom "
1051                               "regulatory domain\n",
1052                               reg_initiator_name(initiator));
1053                 return true;
1054         }
1055
1056         /*
1057          * wiphy->regd will be set once the device has its own
1058          * desired regulatory domain set
1059          */
1060         if (wiphy_strict_alpha2_regd(wiphy) && !wiphy->regd &&
1061             initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE &&
1062             !is_world_regdom(lr->alpha2)) {
1063                 REG_DBG_PRINT("Ignoring regulatory request set by %s "
1064                               "since the driver requires its own regulatory "
1065                               "domain to be set first\n",
1066                               reg_initiator_name(initiator));
1067                 return true;
1068         }
1069
1070         if (reg_request_cell_base(lr))
1071                 return reg_dev_ignore_cell_hint(wiphy);
1072
1073         return false;
1074 }
1075
1076 static bool reg_is_world_roaming(struct wiphy *wiphy)
1077 {
1078         const struct ieee80211_regdomain *cr = get_cfg80211_regdom();
1079         const struct ieee80211_regdomain *wr = get_wiphy_regdom(wiphy);
1080         struct regulatory_request *lr = get_last_request();
1081
1082         if (is_world_regdom(cr->alpha2) || (wr && is_world_regdom(wr->alpha2)))
1083                 return true;
1084
1085         if (lr && lr->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE &&
1086             wiphy->regulatory_flags & REGULATORY_CUSTOM_REG)
1087                 return true;
1088
1089         return false;
1090 }
1091
1092 static void handle_reg_beacon(struct wiphy *wiphy, unsigned int chan_idx,
1093                               struct reg_beacon *reg_beacon)
1094 {
1095         struct ieee80211_supported_band *sband;
1096         struct ieee80211_channel *chan;
1097         bool channel_changed = false;
1098         struct ieee80211_channel chan_before;
1099
1100         sband = wiphy->bands[reg_beacon->chan.band];
1101         chan = &sband->channels[chan_idx];
1102
1103         if (likely(chan->center_freq != reg_beacon->chan.center_freq))
1104                 return;
1105
1106         if (chan->beacon_found)
1107                 return;
1108
1109         chan->beacon_found = true;
1110
1111         if (!reg_is_world_roaming(wiphy))
1112                 return;
1113
1114         if (wiphy->regulatory_flags & REGULATORY_DISABLE_BEACON_HINTS)
1115                 return;
1116
1117         chan_before.center_freq = chan->center_freq;
1118         chan_before.flags = chan->flags;
1119
1120         if (chan->flags & IEEE80211_CHAN_NO_IR) {
1121                 chan->flags &= ~IEEE80211_CHAN_NO_IR;
1122                 channel_changed = true;
1123         }
1124
1125         if (channel_changed)
1126                 nl80211_send_beacon_hint_event(wiphy, &chan_before, chan);
1127 }
1128
1129 /*
1130  * Called when a scan on a wiphy finds a beacon on
1131  * new channel
1132  */
1133 static void wiphy_update_new_beacon(struct wiphy *wiphy,
1134                                     struct reg_beacon *reg_beacon)
1135 {
1136         unsigned int i;
1137         struct ieee80211_supported_band *sband;
1138
1139         if (!wiphy->bands[reg_beacon->chan.band])
1140                 return;
1141
1142         sband = wiphy->bands[reg_beacon->chan.band];
1143
1144         for (i = 0; i < sband->n_channels; i++)
1145                 handle_reg_beacon(wiphy, i, reg_beacon);
1146 }
1147
1148 /*
1149  * Called upon reg changes or a new wiphy is added
1150  */
1151 static void wiphy_update_beacon_reg(struct wiphy *wiphy)
1152 {
1153         unsigned int i;
1154         struct ieee80211_supported_band *sband;
1155         struct reg_beacon *reg_beacon;
1156
1157         list_for_each_entry(reg_beacon, &reg_beacon_list, list) {
1158                 if (!wiphy->bands[reg_beacon->chan.band])
1159                         continue;
1160                 sband = wiphy->bands[reg_beacon->chan.band];
1161                 for (i = 0; i < sband->n_channels; i++)
1162                         handle_reg_beacon(wiphy, i, reg_beacon);
1163         }
1164 }
1165
1166 /* Reap the advantages of previously found beacons */
1167 static void reg_process_beacons(struct wiphy *wiphy)
1168 {
1169         /*
1170          * Means we are just firing up cfg80211, so no beacons would
1171          * have been processed yet.
1172          */
1173         if (!last_request)
1174                 return;
1175         wiphy_update_beacon_reg(wiphy);
1176 }
1177
1178 static bool is_ht40_allowed(struct ieee80211_channel *chan)
1179 {
1180         if (!chan)
1181                 return false;
1182         if (chan->flags & IEEE80211_CHAN_DISABLED)
1183                 return false;
1184         /* This would happen when regulatory rules disallow HT40 completely */
1185         if ((chan->flags & IEEE80211_CHAN_NO_HT40) == IEEE80211_CHAN_NO_HT40)
1186                 return false;
1187         return true;
1188 }
1189
1190 static void reg_process_ht_flags_channel(struct wiphy *wiphy,
1191                                          struct ieee80211_channel *channel)
1192 {
1193         struct ieee80211_supported_band *sband = wiphy->bands[channel->band];
1194         struct ieee80211_channel *channel_before = NULL, *channel_after = NULL;
1195         unsigned int i;
1196
1197         if (!is_ht40_allowed(channel)) {
1198                 channel->flags |= IEEE80211_CHAN_NO_HT40;
1199                 return;
1200         }
1201
1202         /*
1203          * We need to ensure the extension channels exist to
1204          * be able to use HT40- or HT40+, this finds them (or not)
1205          */
1206         for (i = 0; i < sband->n_channels; i++) {
1207                 struct ieee80211_channel *c = &sband->channels[i];
1208
1209                 if (c->center_freq == (channel->center_freq - 20))
1210                         channel_before = c;
1211                 if (c->center_freq == (channel->center_freq + 20))
1212                         channel_after = c;
1213         }
1214
1215         /*
1216          * Please note that this assumes target bandwidth is 20 MHz,
1217          * if that ever changes we also need to change the below logic
1218          * to include that as well.
1219          */
1220         if (!is_ht40_allowed(channel_before))
1221                 channel->flags |= IEEE80211_CHAN_NO_HT40MINUS;
1222         else
1223                 channel->flags &= ~IEEE80211_CHAN_NO_HT40MINUS;
1224
1225         if (!is_ht40_allowed(channel_after))
1226                 channel->flags |= IEEE80211_CHAN_NO_HT40PLUS;
1227         else
1228                 channel->flags &= ~IEEE80211_CHAN_NO_HT40PLUS;
1229 }
1230
1231 static void reg_process_ht_flags_band(struct wiphy *wiphy,
1232                                       struct ieee80211_supported_band *sband)
1233 {
1234         unsigned int i;
1235
1236         if (!sband)
1237                 return;
1238
1239         for (i = 0; i < sband->n_channels; i++)
1240                 reg_process_ht_flags_channel(wiphy, &sband->channels[i]);
1241 }
1242
1243 static void reg_process_ht_flags(struct wiphy *wiphy)
1244 {
1245         enum ieee80211_band band;
1246
1247         if (!wiphy)
1248                 return;
1249
1250         for (band = 0; band < IEEE80211_NUM_BANDS; band++)
1251                 reg_process_ht_flags_band(wiphy, wiphy->bands[band]);
1252 }
1253
1254 static void reg_call_notifier(struct wiphy *wiphy,
1255                               struct regulatory_request *request)
1256 {
1257         if (wiphy->reg_notifier)
1258                 wiphy->reg_notifier(wiphy, request);
1259 }
1260
1261 static void wiphy_update_regulatory(struct wiphy *wiphy,
1262                                     enum nl80211_reg_initiator initiator)
1263 {
1264         enum ieee80211_band band;
1265         struct regulatory_request *lr = get_last_request();
1266
1267         if (ignore_reg_update(wiphy, initiator)) {
1268                 /*
1269                  * Regulatory updates set by CORE are ignored for custom
1270                  * regulatory cards. Let us notify the changes to the driver,
1271                  * as some drivers used this to restore its orig_* reg domain.
1272                  */
1273                 if (initiator == NL80211_REGDOM_SET_BY_CORE &&
1274                     wiphy->regulatory_flags & REGULATORY_CUSTOM_REG)
1275                         reg_call_notifier(wiphy, lr);
1276                 return;
1277         }
1278
1279         lr->dfs_region = get_cfg80211_regdom()->dfs_region;
1280
1281         for (band = 0; band < IEEE80211_NUM_BANDS; band++)
1282                 handle_band(wiphy, initiator, wiphy->bands[band]);
1283
1284         reg_process_beacons(wiphy);
1285         reg_process_ht_flags(wiphy);
1286         reg_call_notifier(wiphy, lr);
1287 }
1288
1289 static void update_all_wiphy_regulatory(enum nl80211_reg_initiator initiator)
1290 {
1291         struct cfg80211_registered_device *rdev;
1292         struct wiphy *wiphy;
1293
1294         ASSERT_RTNL();
1295
1296         list_for_each_entry(rdev, &cfg80211_rdev_list, list) {
1297                 wiphy = &rdev->wiphy;
1298                 wiphy_update_regulatory(wiphy, initiator);
1299         }
1300 }
1301
1302 static void handle_channel_custom(struct wiphy *wiphy,
1303                                   struct ieee80211_channel *chan,
1304                                   const struct ieee80211_regdomain *regd)
1305 {
1306         u32 bw_flags = 0;
1307         const struct ieee80211_reg_rule *reg_rule = NULL;
1308         const struct ieee80211_power_rule *power_rule = NULL;
1309         const struct ieee80211_freq_range *freq_range = NULL;
1310
1311         reg_rule = freq_reg_info_regd(wiphy, MHZ_TO_KHZ(chan->center_freq),
1312                                       regd);
1313
1314         if (IS_ERR(reg_rule)) {
1315                 REG_DBG_PRINT("Disabling freq %d MHz as custom regd has no rule that fits it\n",
1316                               chan->center_freq);
1317                 chan->orig_flags |= IEEE80211_CHAN_DISABLED;
1318                 chan->flags = chan->orig_flags;
1319                 return;
1320         }
1321
1322         chan_reg_rule_print_dbg(chan, reg_rule);
1323
1324         power_rule = &reg_rule->power_rule;
1325         freq_range = &reg_rule->freq_range;
1326
1327         if (freq_range->max_bandwidth_khz < MHZ_TO_KHZ(40))
1328                 bw_flags = IEEE80211_CHAN_NO_HT40;
1329         if (freq_range->max_bandwidth_khz < MHZ_TO_KHZ(80))
1330                 bw_flags |= IEEE80211_CHAN_NO_80MHZ;
1331         if (freq_range->max_bandwidth_khz < MHZ_TO_KHZ(160))
1332                 bw_flags |= IEEE80211_CHAN_NO_160MHZ;
1333
1334         chan->flags |= map_regdom_flags(reg_rule->flags) | bw_flags;
1335         chan->max_antenna_gain = (int) MBI_TO_DBI(power_rule->max_antenna_gain);
1336         chan->max_reg_power = chan->max_power =
1337                 (int) MBM_TO_DBM(power_rule->max_eirp);
1338 }
1339
1340 static void handle_band_custom(struct wiphy *wiphy,
1341                                struct ieee80211_supported_band *sband,
1342                                const struct ieee80211_regdomain *regd)
1343 {
1344         unsigned int i;
1345
1346         if (!sband)
1347                 return;
1348
1349         for (i = 0; i < sband->n_channels; i++)
1350                 handle_channel_custom(wiphy, &sband->channels[i], regd);
1351 }
1352
1353 /* Used by drivers prior to wiphy registration */
1354 void wiphy_apply_custom_regulatory(struct wiphy *wiphy,
1355                                    const struct ieee80211_regdomain *regd)
1356 {
1357         enum ieee80211_band band;
1358         unsigned int bands_set = 0;
1359
1360         WARN(!(wiphy->regulatory_flags & REGULATORY_CUSTOM_REG),
1361              "wiphy should have REGULATORY_CUSTOM_REG\n");
1362         wiphy->regulatory_flags |= REGULATORY_CUSTOM_REG;
1363
1364         for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
1365                 if (!wiphy->bands[band])
1366                         continue;
1367                 handle_band_custom(wiphy, wiphy->bands[band], regd);
1368                 bands_set++;
1369         }
1370
1371         /*
1372          * no point in calling this if it won't have any effect
1373          * on your device's supported bands.
1374          */
1375         WARN_ON(!bands_set);
1376 }
1377 EXPORT_SYMBOL(wiphy_apply_custom_regulatory);
1378
1379 static void reg_set_request_processed(void)
1380 {
1381         bool need_more_processing = false;
1382         struct regulatory_request *lr = get_last_request();
1383
1384         lr->processed = true;
1385
1386         spin_lock(&reg_requests_lock);
1387         if (!list_empty(&reg_requests_list))
1388                 need_more_processing = true;
1389         spin_unlock(&reg_requests_lock);
1390
1391         if (lr->initiator == NL80211_REGDOM_SET_BY_USER)
1392                 cancel_delayed_work(&reg_timeout);
1393
1394         if (need_more_processing)
1395                 schedule_work(&reg_work);
1396 }
1397
1398 /**
1399  * reg_process_hint_core - process core regulatory requests
1400  * @pending_request: a pending core regulatory request
1401  *
1402  * The wireless subsystem can use this function to process
1403  * a regulatory request issued by the regulatory core.
1404  *
1405  * Returns one of the different reg request treatment values.
1406  */
1407 static enum reg_request_treatment
1408 reg_process_hint_core(struct regulatory_request *core_request)
1409 {
1410
1411         core_request->intersect = false;
1412         core_request->processed = false;
1413
1414         reg_update_last_request(core_request);
1415
1416         return reg_call_crda(core_request);
1417 }
1418
1419 static enum reg_request_treatment
1420 __reg_process_hint_user(struct regulatory_request *user_request)
1421 {
1422         struct regulatory_request *lr = get_last_request();
1423
1424         if (reg_request_cell_base(user_request))
1425                 return reg_ignore_cell_hint(user_request);
1426
1427         if (reg_request_cell_base(lr))
1428                 return REG_REQ_IGNORE;
1429
1430         if (lr->initiator == NL80211_REGDOM_SET_BY_COUNTRY_IE)
1431                 return REG_REQ_INTERSECT;
1432         /*
1433          * If the user knows better the user should set the regdom
1434          * to their country before the IE is picked up
1435          */
1436         if (lr->initiator == NL80211_REGDOM_SET_BY_USER &&
1437             lr->intersect)
1438                 return REG_REQ_IGNORE;
1439         /*
1440          * Process user requests only after previous user/driver/core
1441          * requests have been processed
1442          */
1443         if ((lr->initiator == NL80211_REGDOM_SET_BY_CORE ||
1444              lr->initiator == NL80211_REGDOM_SET_BY_DRIVER ||
1445              lr->initiator == NL80211_REGDOM_SET_BY_USER) &&
1446             regdom_changes(lr->alpha2))
1447                 return REG_REQ_IGNORE;
1448
1449         if (!regdom_changes(user_request->alpha2))
1450                 return REG_REQ_ALREADY_SET;
1451
1452         return REG_REQ_OK;
1453 }
1454
1455 /**
1456  * reg_process_hint_user - process user regulatory requests
1457  * @user_request: a pending user regulatory request
1458  *
1459  * The wireless subsystem can use this function to process
1460  * a regulatory request initiated by userspace.
1461  *
1462  * Returns one of the different reg request treatment values.
1463  */
1464 static enum reg_request_treatment
1465 reg_process_hint_user(struct regulatory_request *user_request)
1466 {
1467         enum reg_request_treatment treatment;
1468
1469         treatment = __reg_process_hint_user(user_request);
1470         if (treatment == REG_REQ_IGNORE ||
1471             treatment == REG_REQ_ALREADY_SET) {
1472                 kfree(user_request);
1473                 return treatment;
1474         }
1475
1476         user_request->intersect = treatment == REG_REQ_INTERSECT;
1477         user_request->processed = false;
1478
1479         reg_update_last_request(user_request);
1480
1481         user_alpha2[0] = user_request->alpha2[0];
1482         user_alpha2[1] = user_request->alpha2[1];
1483
1484         return reg_call_crda(user_request);
1485 }
1486
1487 static enum reg_request_treatment
1488 __reg_process_hint_driver(struct regulatory_request *driver_request)
1489 {
1490         struct regulatory_request *lr = get_last_request();
1491
1492         if (lr->initiator == NL80211_REGDOM_SET_BY_CORE) {
1493                 if (regdom_changes(driver_request->alpha2))
1494                         return REG_REQ_OK;
1495                 return REG_REQ_ALREADY_SET;
1496         }
1497
1498         /*
1499          * This would happen if you unplug and plug your card
1500          * back in or if you add a new device for which the previously
1501          * loaded card also agrees on the regulatory domain.
1502          */
1503         if (lr->initiator == NL80211_REGDOM_SET_BY_DRIVER &&
1504             !regdom_changes(driver_request->alpha2))
1505                 return REG_REQ_ALREADY_SET;
1506
1507         return REG_REQ_INTERSECT;
1508 }
1509
1510 /**
1511  * reg_process_hint_driver - process driver regulatory requests
1512  * @driver_request: a pending driver regulatory request
1513  *
1514  * The wireless subsystem can use this function to process
1515  * a regulatory request issued by an 802.11 driver.
1516  *
1517  * Returns one of the different reg request treatment values.
1518  */
1519 static enum reg_request_treatment
1520 reg_process_hint_driver(struct wiphy *wiphy,
1521                         struct regulatory_request *driver_request)
1522 {
1523         const struct ieee80211_regdomain *regd;
1524         enum reg_request_treatment treatment;
1525
1526         treatment = __reg_process_hint_driver(driver_request);
1527
1528         switch (treatment) {
1529         case REG_REQ_OK:
1530                 break;
1531         case REG_REQ_IGNORE:
1532                 kfree(driver_request);
1533                 return treatment;
1534         case REG_REQ_INTERSECT:
1535                 /* fall through */
1536         case REG_REQ_ALREADY_SET:
1537                 regd = reg_copy_regd(get_cfg80211_regdom());
1538                 if (IS_ERR(regd)) {
1539                         kfree(driver_request);
1540                         return REG_REQ_IGNORE;
1541                 }
1542                 rcu_assign_pointer(wiphy->regd, regd);
1543         }
1544
1545
1546         driver_request->intersect = treatment == REG_REQ_INTERSECT;
1547         driver_request->processed = false;
1548
1549         reg_update_last_request(driver_request);
1550
1551         /*
1552          * Since CRDA will not be called in this case as we already
1553          * have applied the requested regulatory domain before we just
1554          * inform userspace we have processed the request
1555          */
1556         if (treatment == REG_REQ_ALREADY_SET) {
1557                 nl80211_send_reg_change_event(driver_request);
1558                 reg_set_request_processed();
1559                 return treatment;
1560         }
1561
1562         return reg_call_crda(driver_request);
1563 }
1564
1565 static enum reg_request_treatment
1566 __reg_process_hint_country_ie(struct wiphy *wiphy,
1567                               struct regulatory_request *country_ie_request)
1568 {
1569         struct wiphy *last_wiphy = NULL;
1570         struct regulatory_request *lr = get_last_request();
1571
1572         if (reg_request_cell_base(lr)) {
1573                 /* Trust a Cell base station over the AP's country IE */
1574                 if (regdom_changes(country_ie_request->alpha2))
1575                         return REG_REQ_IGNORE;
1576                 return REG_REQ_ALREADY_SET;
1577         } else {
1578                 if (wiphy->regulatory_flags & REGULATORY_COUNTRY_IE_IGNORE)
1579                         return REG_REQ_IGNORE;
1580         }
1581
1582         if (unlikely(!is_an_alpha2(country_ie_request->alpha2)))
1583                 return -EINVAL;
1584
1585         if (lr->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE)
1586                 return REG_REQ_OK;
1587
1588         last_wiphy = wiphy_idx_to_wiphy(lr->wiphy_idx);
1589
1590         if (last_wiphy != wiphy) {
1591                 /*
1592                  * Two cards with two APs claiming different
1593                  * Country IE alpha2s. We could
1594                  * intersect them, but that seems unlikely
1595                  * to be correct. Reject second one for now.
1596                  */
1597                 if (regdom_changes(country_ie_request->alpha2))
1598                         return REG_REQ_IGNORE;
1599                 return REG_REQ_ALREADY_SET;
1600         }
1601         /*
1602          * Two consecutive Country IE hints on the same wiphy.
1603          * This should be picked up early by the driver/stack
1604          */
1605         if (WARN_ON(regdom_changes(country_ie_request->alpha2)))
1606                 return REG_REQ_OK;
1607         return REG_REQ_ALREADY_SET;
1608 }
1609
1610 /**
1611  * reg_process_hint_country_ie - process regulatory requests from country IEs
1612  * @country_ie_request: a regulatory request from a country IE
1613  *
1614  * The wireless subsystem can use this function to process
1615  * a regulatory request issued by a country Information Element.
1616  *
1617  * Returns one of the different reg request treatment values.
1618  */
1619 static enum reg_request_treatment
1620 reg_process_hint_country_ie(struct wiphy *wiphy,
1621                             struct regulatory_request *country_ie_request)
1622 {
1623         enum reg_request_treatment treatment;
1624
1625         treatment = __reg_process_hint_country_ie(wiphy, country_ie_request);
1626
1627         switch (treatment) {
1628         case REG_REQ_OK:
1629                 break;
1630         case REG_REQ_IGNORE:
1631                 /* fall through */
1632         case REG_REQ_ALREADY_SET:
1633                 kfree(country_ie_request);
1634                 return treatment;
1635         case REG_REQ_INTERSECT:
1636                 kfree(country_ie_request);
1637                 /*
1638                  * This doesn't happen yet, not sure we
1639                  * ever want to support it for this case.
1640                  */
1641                 WARN_ONCE(1, "Unexpected intersection for country IEs");
1642                 return REG_REQ_IGNORE;
1643         }
1644
1645         country_ie_request->intersect = false;
1646         country_ie_request->processed = false;
1647
1648         reg_update_last_request(country_ie_request);
1649
1650         return reg_call_crda(country_ie_request);
1651 }
1652
1653 /* This processes *all* regulatory hints */
1654 static void reg_process_hint(struct regulatory_request *reg_request)
1655 {
1656         struct wiphy *wiphy = NULL;
1657         enum reg_request_treatment treatment;
1658
1659         if (WARN_ON(!reg_request->alpha2))
1660                 return;
1661
1662         if (reg_request->wiphy_idx != WIPHY_IDX_INVALID)
1663                 wiphy = wiphy_idx_to_wiphy(reg_request->wiphy_idx);
1664
1665         if (reg_request->initiator == NL80211_REGDOM_SET_BY_DRIVER && !wiphy) {
1666                 kfree(reg_request);
1667                 return;
1668         }
1669
1670         switch (reg_request->initiator) {
1671         case NL80211_REGDOM_SET_BY_CORE:
1672                 reg_process_hint_core(reg_request);
1673                 return;
1674         case NL80211_REGDOM_SET_BY_USER:
1675                 treatment = reg_process_hint_user(reg_request);
1676                 if (treatment == REG_REQ_OK ||
1677                     treatment == REG_REQ_ALREADY_SET)
1678                         return;
1679                 schedule_delayed_work(&reg_timeout, msecs_to_jiffies(3142));
1680                 return;
1681         case NL80211_REGDOM_SET_BY_DRIVER:
1682                 treatment = reg_process_hint_driver(wiphy, reg_request);
1683                 break;
1684         case NL80211_REGDOM_SET_BY_COUNTRY_IE:
1685                 treatment = reg_process_hint_country_ie(wiphy, reg_request);
1686                 break;
1687         default:
1688                 WARN(1, "invalid initiator %d\n", reg_request->initiator);
1689                 return;
1690         }
1691
1692         /* This is required so that the orig_* parameters are saved */
1693         if (treatment == REG_REQ_ALREADY_SET && wiphy &&
1694             wiphy->regulatory_flags & REGULATORY_STRICT_REG)
1695                 wiphy_update_regulatory(wiphy, reg_request->initiator);
1696 }
1697
1698 /*
1699  * Processes regulatory hints, this is all the NL80211_REGDOM_SET_BY_*
1700  * Regulatory hints come on a first come first serve basis and we
1701  * must process each one atomically.
1702  */
1703 static void reg_process_pending_hints(void)
1704 {
1705         struct regulatory_request *reg_request, *lr;
1706
1707         lr = get_last_request();
1708
1709         /* When last_request->processed becomes true this will be rescheduled */
1710         if (lr && !lr->processed) {
1711                 REG_DBG_PRINT("Pending regulatory request, waiting for it to be processed...\n");
1712                 return;
1713         }
1714
1715         spin_lock(&reg_requests_lock);
1716
1717         if (list_empty(&reg_requests_list)) {
1718                 spin_unlock(&reg_requests_lock);
1719                 return;
1720         }
1721
1722         reg_request = list_first_entry(&reg_requests_list,
1723                                        struct regulatory_request,
1724                                        list);
1725         list_del_init(&reg_request->list);
1726
1727         spin_unlock(&reg_requests_lock);
1728
1729         reg_process_hint(reg_request);
1730 }
1731
1732 /* Processes beacon hints -- this has nothing to do with country IEs */
1733 static void reg_process_pending_beacon_hints(void)
1734 {
1735         struct cfg80211_registered_device *rdev;
1736         struct reg_beacon *pending_beacon, *tmp;
1737
1738         /* This goes through the _pending_ beacon list */
1739         spin_lock_bh(&reg_pending_beacons_lock);
1740
1741         list_for_each_entry_safe(pending_beacon, tmp,
1742                                  &reg_pending_beacons, list) {
1743                 list_del_init(&pending_beacon->list);
1744
1745                 /* Applies the beacon hint to current wiphys */
1746                 list_for_each_entry(rdev, &cfg80211_rdev_list, list)
1747                         wiphy_update_new_beacon(&rdev->wiphy, pending_beacon);
1748
1749                 /* Remembers the beacon hint for new wiphys or reg changes */
1750                 list_add_tail(&pending_beacon->list, &reg_beacon_list);
1751         }
1752
1753         spin_unlock_bh(&reg_pending_beacons_lock);
1754 }
1755
1756 static void reg_todo(struct work_struct *work)
1757 {
1758         rtnl_lock();
1759         reg_process_pending_hints();
1760         reg_process_pending_beacon_hints();
1761         rtnl_unlock();
1762 }
1763
1764 static void queue_regulatory_request(struct regulatory_request *request)
1765 {
1766         request->alpha2[0] = toupper(request->alpha2[0]);
1767         request->alpha2[1] = toupper(request->alpha2[1]);
1768
1769         spin_lock(&reg_requests_lock);
1770         list_add_tail(&request->list, &reg_requests_list);
1771         spin_unlock(&reg_requests_lock);
1772
1773         schedule_work(&reg_work);
1774 }
1775
1776 /*
1777  * Core regulatory hint -- happens during cfg80211_init()
1778  * and when we restore regulatory settings.
1779  */
1780 static int regulatory_hint_core(const char *alpha2)
1781 {
1782         struct regulatory_request *request;
1783
1784         request = kzalloc(sizeof(struct regulatory_request), GFP_KERNEL);
1785         if (!request)
1786                 return -ENOMEM;
1787
1788         request->alpha2[0] = alpha2[0];
1789         request->alpha2[1] = alpha2[1];
1790         request->initiator = NL80211_REGDOM_SET_BY_CORE;
1791
1792         queue_regulatory_request(request);
1793
1794         return 0;
1795 }
1796
1797 /* User hints */
1798 int regulatory_hint_user(const char *alpha2,
1799                          enum nl80211_user_reg_hint_type user_reg_hint_type)
1800 {
1801         struct regulatory_request *request;
1802
1803         if (WARN_ON(!alpha2))
1804                 return -EINVAL;
1805
1806         request = kzalloc(sizeof(struct regulatory_request), GFP_KERNEL);
1807         if (!request)
1808                 return -ENOMEM;
1809
1810         request->wiphy_idx = WIPHY_IDX_INVALID;
1811         request->alpha2[0] = alpha2[0];
1812         request->alpha2[1] = alpha2[1];
1813         request->initiator = NL80211_REGDOM_SET_BY_USER;
1814         request->user_reg_hint_type = user_reg_hint_type;
1815
1816         queue_regulatory_request(request);
1817
1818         return 0;
1819 }
1820
1821 /* Driver hints */
1822 int regulatory_hint(struct wiphy *wiphy, const char *alpha2)
1823 {
1824         struct regulatory_request *request;
1825
1826         if (WARN_ON(!alpha2 || !wiphy))
1827                 return -EINVAL;
1828
1829         request = kzalloc(sizeof(struct regulatory_request), GFP_KERNEL);
1830         if (!request)
1831                 return -ENOMEM;
1832
1833         request->wiphy_idx = get_wiphy_idx(wiphy);
1834
1835         request->alpha2[0] = alpha2[0];
1836         request->alpha2[1] = alpha2[1];
1837         request->initiator = NL80211_REGDOM_SET_BY_DRIVER;
1838
1839         queue_regulatory_request(request);
1840
1841         return 0;
1842 }
1843 EXPORT_SYMBOL(regulatory_hint);
1844
1845 void regulatory_hint_country_ie(struct wiphy *wiphy, enum ieee80211_band band,
1846                                 const u8 *country_ie, u8 country_ie_len)
1847 {
1848         char alpha2[2];
1849         enum environment_cap env = ENVIRON_ANY;
1850         struct regulatory_request *request = NULL, *lr;
1851
1852         /* IE len must be evenly divisible by 2 */
1853         if (country_ie_len & 0x01)
1854                 return;
1855
1856         if (country_ie_len < IEEE80211_COUNTRY_IE_MIN_LEN)
1857                 return;
1858
1859         request = kzalloc(sizeof(*request), GFP_KERNEL);
1860         if (!request)
1861                 return;
1862
1863         alpha2[0] = country_ie[0];
1864         alpha2[1] = country_ie[1];
1865
1866         if (country_ie[2] == 'I')
1867                 env = ENVIRON_INDOOR;
1868         else if (country_ie[2] == 'O')
1869                 env = ENVIRON_OUTDOOR;
1870
1871         rcu_read_lock();
1872         lr = get_last_request();
1873
1874         if (unlikely(!lr))
1875                 goto out;
1876
1877         /*
1878          * We will run this only upon a successful connection on cfg80211.
1879          * We leave conflict resolution to the workqueue, where can hold
1880          * the RTNL.
1881          */
1882         if (lr->initiator == NL80211_REGDOM_SET_BY_COUNTRY_IE &&
1883             lr->wiphy_idx != WIPHY_IDX_INVALID)
1884                 goto out;
1885
1886         request->wiphy_idx = get_wiphy_idx(wiphy);
1887         request->alpha2[0] = alpha2[0];
1888         request->alpha2[1] = alpha2[1];
1889         request->initiator = NL80211_REGDOM_SET_BY_COUNTRY_IE;
1890         request->country_ie_env = env;
1891
1892         queue_regulatory_request(request);
1893         request = NULL;
1894 out:
1895         kfree(request);
1896         rcu_read_unlock();
1897 }
1898
1899 static void restore_alpha2(char *alpha2, bool reset_user)
1900 {
1901         /* indicates there is no alpha2 to consider for restoration */
1902         alpha2[0] = '9';
1903         alpha2[1] = '7';
1904
1905         /* The user setting has precedence over the module parameter */
1906         if (is_user_regdom_saved()) {
1907                 /* Unless we're asked to ignore it and reset it */
1908                 if (reset_user) {
1909                         REG_DBG_PRINT("Restoring regulatory settings including user preference\n");
1910                         user_alpha2[0] = '9';
1911                         user_alpha2[1] = '7';
1912
1913                         /*
1914                          * If we're ignoring user settings, we still need to
1915                          * check the module parameter to ensure we put things
1916                          * back as they were for a full restore.
1917                          */
1918                         if (!is_world_regdom(ieee80211_regdom)) {
1919                                 REG_DBG_PRINT("Keeping preference on module parameter ieee80211_regdom: %c%c\n",
1920                                               ieee80211_regdom[0], ieee80211_regdom[1]);
1921                                 alpha2[0] = ieee80211_regdom[0];
1922                                 alpha2[1] = ieee80211_regdom[1];
1923                         }
1924                 } else {
1925                         REG_DBG_PRINT("Restoring regulatory settings while preserving user preference for: %c%c\n",
1926                                       user_alpha2[0], user_alpha2[1]);
1927                         alpha2[0] = user_alpha2[0];
1928                         alpha2[1] = user_alpha2[1];
1929                 }
1930         } else if (!is_world_regdom(ieee80211_regdom)) {
1931                 REG_DBG_PRINT("Keeping preference on module parameter ieee80211_regdom: %c%c\n",
1932                               ieee80211_regdom[0], ieee80211_regdom[1]);
1933                 alpha2[0] = ieee80211_regdom[0];
1934                 alpha2[1] = ieee80211_regdom[1];
1935         } else
1936                 REG_DBG_PRINT("Restoring regulatory settings\n");
1937 }
1938
1939 static void restore_custom_reg_settings(struct wiphy *wiphy)
1940 {
1941         struct ieee80211_supported_band *sband;
1942         enum ieee80211_band band;
1943         struct ieee80211_channel *chan;
1944         int i;
1945
1946         for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
1947                 sband = wiphy->bands[band];
1948                 if (!sband)
1949                         continue;
1950                 for (i = 0; i < sband->n_channels; i++) {
1951                         chan = &sband->channels[i];
1952                         chan->flags = chan->orig_flags;
1953                         chan->max_antenna_gain = chan->orig_mag;
1954                         chan->max_power = chan->orig_mpwr;
1955                         chan->beacon_found = false;
1956                 }
1957         }
1958 }
1959
1960 /*
1961  * Restoring regulatory settings involves ingoring any
1962  * possibly stale country IE information and user regulatory
1963  * settings if so desired, this includes any beacon hints
1964  * learned as we could have traveled outside to another country
1965  * after disconnection. To restore regulatory settings we do
1966  * exactly what we did at bootup:
1967  *
1968  *   - send a core regulatory hint
1969  *   - send a user regulatory hint if applicable
1970  *
1971  * Device drivers that send a regulatory hint for a specific country
1972  * keep their own regulatory domain on wiphy->regd so that does does
1973  * not need to be remembered.
1974  */
1975 static void restore_regulatory_settings(bool reset_user)
1976 {
1977         char alpha2[2];
1978         char world_alpha2[2];
1979         struct reg_beacon *reg_beacon, *btmp;
1980         struct regulatory_request *reg_request, *tmp;
1981         LIST_HEAD(tmp_reg_req_list);
1982         struct cfg80211_registered_device *rdev;
1983
1984         ASSERT_RTNL();
1985
1986         reset_regdomains(true, &world_regdom);
1987         restore_alpha2(alpha2, reset_user);
1988
1989         /*
1990          * If there's any pending requests we simply
1991          * stash them to a temporary pending queue and
1992          * add then after we've restored regulatory
1993          * settings.
1994          */
1995         spin_lock(&reg_requests_lock);
1996         list_for_each_entry_safe(reg_request, tmp, &reg_requests_list, list) {
1997                 if (reg_request->initiator != NL80211_REGDOM_SET_BY_USER)
1998                         continue;
1999                 list_move_tail(&reg_request->list, &tmp_reg_req_list);
2000         }
2001         spin_unlock(&reg_requests_lock);
2002
2003         /* Clear beacon hints */
2004         spin_lock_bh(&reg_pending_beacons_lock);
2005         list_for_each_entry_safe(reg_beacon, btmp, &reg_pending_beacons, list) {
2006                 list_del(&reg_beacon->list);
2007                 kfree(reg_beacon);
2008         }
2009         spin_unlock_bh(&reg_pending_beacons_lock);
2010
2011         list_for_each_entry_safe(reg_beacon, btmp, &reg_beacon_list, list) {
2012                 list_del(&reg_beacon->list);
2013                 kfree(reg_beacon);
2014         }
2015
2016         /* First restore to the basic regulatory settings */
2017         world_alpha2[0] = cfg80211_world_regdom->alpha2[0];
2018         world_alpha2[1] = cfg80211_world_regdom->alpha2[1];
2019
2020         list_for_each_entry(rdev, &cfg80211_rdev_list, list) {
2021                 if (rdev->wiphy.regulatory_flags & REGULATORY_CUSTOM_REG)
2022                         restore_custom_reg_settings(&rdev->wiphy);
2023         }
2024
2025         regulatory_hint_core(world_alpha2);
2026
2027         /*
2028          * This restores the ieee80211_regdom module parameter
2029          * preference or the last user requested regulatory
2030          * settings, user regulatory settings takes precedence.
2031          */
2032         if (is_an_alpha2(alpha2))
2033                 regulatory_hint_user(user_alpha2, NL80211_USER_REG_HINT_USER);
2034
2035         spin_lock(&reg_requests_lock);
2036         list_splice_tail_init(&tmp_reg_req_list, &reg_requests_list);
2037         spin_unlock(&reg_requests_lock);
2038
2039         REG_DBG_PRINT("Kicking the queue\n");
2040
2041         schedule_work(&reg_work);
2042 }
2043
2044 void regulatory_hint_disconnect(void)
2045 {
2046         REG_DBG_PRINT("All devices are disconnected, going to restore regulatory settings\n");
2047         restore_regulatory_settings(false);
2048 }
2049
2050 static bool freq_is_chan_12_13_14(u16 freq)
2051 {
2052         if (freq == ieee80211_channel_to_frequency(12, IEEE80211_BAND_2GHZ) ||
2053             freq == ieee80211_channel_to_frequency(13, IEEE80211_BAND_2GHZ) ||
2054             freq == ieee80211_channel_to_frequency(14, IEEE80211_BAND_2GHZ))
2055                 return true;
2056         return false;
2057 }
2058
2059 static bool pending_reg_beacon(struct ieee80211_channel *beacon_chan)
2060 {
2061         struct reg_beacon *pending_beacon;
2062
2063         list_for_each_entry(pending_beacon, &reg_pending_beacons, list)
2064                 if (beacon_chan->center_freq ==
2065                     pending_beacon->chan.center_freq)
2066                         return true;
2067         return false;
2068 }
2069
2070 int regulatory_hint_found_beacon(struct wiphy *wiphy,
2071                                  struct ieee80211_channel *beacon_chan,
2072                                  gfp_t gfp)
2073 {
2074         struct reg_beacon *reg_beacon;
2075         bool processing;
2076
2077         if (beacon_chan->beacon_found ||
2078             beacon_chan->flags & IEEE80211_CHAN_RADAR ||
2079             (beacon_chan->band == IEEE80211_BAND_2GHZ &&
2080              !freq_is_chan_12_13_14(beacon_chan->center_freq)))
2081                 return 0;
2082
2083         spin_lock_bh(&reg_pending_beacons_lock);
2084         processing = pending_reg_beacon(beacon_chan);
2085         spin_unlock_bh(&reg_pending_beacons_lock);
2086
2087         if (processing)
2088                 return 0;
2089
2090         reg_beacon = kzalloc(sizeof(struct reg_beacon), gfp);
2091         if (!reg_beacon)
2092                 return -ENOMEM;
2093
2094         REG_DBG_PRINT("Found new beacon on frequency: %d MHz (Ch %d) on %s\n",
2095                       beacon_chan->center_freq,
2096                       ieee80211_frequency_to_channel(beacon_chan->center_freq),
2097                       wiphy_name(wiphy));
2098
2099         memcpy(&reg_beacon->chan, beacon_chan,
2100                sizeof(struct ieee80211_channel));
2101
2102         /*
2103          * Since we can be called from BH or and non-BH context
2104          * we must use spin_lock_bh()
2105          */
2106         spin_lock_bh(&reg_pending_beacons_lock);
2107         list_add_tail(&reg_beacon->list, &reg_pending_beacons);
2108         spin_unlock_bh(&reg_pending_beacons_lock);
2109
2110         schedule_work(&reg_work);
2111
2112         return 0;
2113 }
2114
2115 static void print_rd_rules(const struct ieee80211_regdomain *rd)
2116 {
2117         unsigned int i;
2118         const struct ieee80211_reg_rule *reg_rule = NULL;
2119         const struct ieee80211_freq_range *freq_range = NULL;
2120         const struct ieee80211_power_rule *power_rule = NULL;
2121
2122         pr_info("  (start_freq - end_freq @ bandwidth), (max_antenna_gain, max_eirp)\n");
2123
2124         for (i = 0; i < rd->n_reg_rules; i++) {
2125                 reg_rule = &rd->reg_rules[i];
2126                 freq_range = &reg_rule->freq_range;
2127                 power_rule = &reg_rule->power_rule;
2128
2129                 /*
2130                  * There may not be documentation for max antenna gain
2131                  * in certain regions
2132                  */
2133                 if (power_rule->max_antenna_gain)
2134                         pr_info("  (%d KHz - %d KHz @ %d KHz), (%d mBi, %d mBm)\n",
2135                                 freq_range->start_freq_khz,
2136                                 freq_range->end_freq_khz,
2137                                 freq_range->max_bandwidth_khz,
2138                                 power_rule->max_antenna_gain,
2139                                 power_rule->max_eirp);
2140                 else
2141                         pr_info("  (%d KHz - %d KHz @ %d KHz), (N/A, %d mBm)\n",
2142                                 freq_range->start_freq_khz,
2143                                 freq_range->end_freq_khz,
2144                                 freq_range->max_bandwidth_khz,
2145                                 power_rule->max_eirp);
2146         }
2147 }
2148
2149 bool reg_supported_dfs_region(enum nl80211_dfs_regions dfs_region)
2150 {
2151         switch (dfs_region) {
2152         case NL80211_DFS_UNSET:
2153         case NL80211_DFS_FCC:
2154         case NL80211_DFS_ETSI:
2155         case NL80211_DFS_JP:
2156                 return true;
2157         default:
2158                 REG_DBG_PRINT("Ignoring uknown DFS master region: %d\n",
2159                               dfs_region);
2160                 return false;
2161         }
2162 }
2163
2164 static void print_regdomain(const struct ieee80211_regdomain *rd)
2165 {
2166         struct regulatory_request *lr = get_last_request();
2167
2168         if (is_intersected_alpha2(rd->alpha2)) {
2169                 if (lr->initiator == NL80211_REGDOM_SET_BY_COUNTRY_IE) {
2170                         struct cfg80211_registered_device *rdev;
2171                         rdev = cfg80211_rdev_by_wiphy_idx(lr->wiphy_idx);
2172                         if (rdev) {
2173                                 pr_info("Current regulatory domain updated by AP to: %c%c\n",
2174                                         rdev->country_ie_alpha2[0],
2175                                         rdev->country_ie_alpha2[1]);
2176                         } else
2177                                 pr_info("Current regulatory domain intersected:\n");
2178                 } else
2179                         pr_info("Current regulatory domain intersected:\n");
2180         } else if (is_world_regdom(rd->alpha2)) {
2181                 pr_info("World regulatory domain updated:\n");
2182         } else {
2183                 if (is_unknown_alpha2(rd->alpha2))
2184                         pr_info("Regulatory domain changed to driver built-in settings (unknown country)\n");
2185                 else {
2186                         if (reg_request_cell_base(lr))
2187                                 pr_info("Regulatory domain changed to country: %c%c by Cell Station\n",
2188                                         rd->alpha2[0], rd->alpha2[1]);
2189                         else
2190                                 pr_info("Regulatory domain changed to country: %c%c\n",
2191                                         rd->alpha2[0], rd->alpha2[1]);
2192                 }
2193         }
2194
2195         pr_info(" DFS Master region: %s", reg_dfs_region_str(rd->dfs_region));
2196         print_rd_rules(rd);
2197 }
2198
2199 static void print_regdomain_info(const struct ieee80211_regdomain *rd)
2200 {
2201         pr_info("Regulatory domain: %c%c\n", rd->alpha2[0], rd->alpha2[1]);
2202         print_rd_rules(rd);
2203 }
2204
2205 static int reg_set_rd_core(const struct ieee80211_regdomain *rd)
2206 {
2207         if (!is_world_regdom(rd->alpha2))
2208                 return -EINVAL;
2209         update_world_regdomain(rd);
2210         return 0;
2211 }
2212
2213 static int reg_set_rd_user(const struct ieee80211_regdomain *rd,
2214                            struct regulatory_request *user_request)
2215 {
2216         const struct ieee80211_regdomain *intersected_rd = NULL;
2217
2218         if (is_world_regdom(rd->alpha2))
2219                 return -EINVAL;
2220
2221         if (!regdom_changes(rd->alpha2))
2222                 return -EALREADY;
2223
2224         if (!is_valid_rd(rd)) {
2225                 pr_err("Invalid regulatory domain detected:\n");
2226                 print_regdomain_info(rd);
2227                 return -EINVAL;
2228         }
2229
2230         if (!user_request->intersect) {
2231                 reset_regdomains(false, rd);
2232                 return 0;
2233         }
2234
2235         intersected_rd = regdom_intersect(rd, get_cfg80211_regdom());
2236         if (!intersected_rd)
2237                 return -EINVAL;
2238
2239         kfree(rd);
2240         rd = NULL;
2241         reset_regdomains(false, intersected_rd);
2242
2243         return 0;
2244 }
2245
2246 static int reg_set_rd_driver(const struct ieee80211_regdomain *rd,
2247                              struct regulatory_request *driver_request)
2248 {
2249         const struct ieee80211_regdomain *regd;
2250         const struct ieee80211_regdomain *intersected_rd = NULL;
2251         const struct ieee80211_regdomain *tmp;
2252         struct wiphy *request_wiphy;
2253
2254         if (is_world_regdom(rd->alpha2))
2255                 return -EINVAL;
2256
2257         if (!regdom_changes(rd->alpha2))
2258                 return -EALREADY;
2259
2260         if (!is_valid_rd(rd)) {
2261                 pr_err("Invalid regulatory domain detected:\n");
2262                 print_regdomain_info(rd);
2263                 return -EINVAL;
2264         }
2265
2266         request_wiphy = wiphy_idx_to_wiphy(driver_request->wiphy_idx);
2267         if (!request_wiphy) {
2268                 schedule_delayed_work(&reg_timeout, 0);
2269                 return -ENODEV;
2270         }
2271
2272         if (!driver_request->intersect) {
2273                 if (request_wiphy->regd)
2274                         return -EALREADY;
2275
2276                 regd = reg_copy_regd(rd);
2277                 if (IS_ERR(regd))
2278                         return PTR_ERR(regd);
2279
2280                 rcu_assign_pointer(request_wiphy->regd, regd);
2281                 reset_regdomains(false, rd);
2282                 return 0;
2283         }
2284
2285         intersected_rd = regdom_intersect(rd, get_cfg80211_regdom());
2286         if (!intersected_rd)
2287                 return -EINVAL;
2288
2289         /*
2290          * We can trash what CRDA provided now.
2291          * However if a driver requested this specific regulatory
2292          * domain we keep it for its private use
2293          */
2294         tmp = get_wiphy_regdom(request_wiphy);
2295         rcu_assign_pointer(request_wiphy->regd, rd);
2296         rcu_free_regdom(tmp);
2297
2298         rd = NULL;
2299
2300         reset_regdomains(false, intersected_rd);
2301
2302         return 0;
2303 }
2304
2305 static int reg_set_rd_country_ie(const struct ieee80211_regdomain *rd,
2306                                  struct regulatory_request *country_ie_request)
2307 {
2308         struct wiphy *request_wiphy;
2309
2310         if (!is_alpha2_set(rd->alpha2) && !is_an_alpha2(rd->alpha2) &&
2311             !is_unknown_alpha2(rd->alpha2))
2312                 return -EINVAL;
2313
2314         /*
2315          * Lets only bother proceeding on the same alpha2 if the current
2316          * rd is non static (it means CRDA was present and was used last)
2317          * and the pending request came in from a country IE
2318          */
2319
2320         if (!is_valid_rd(rd)) {
2321                 pr_err("Invalid regulatory domain detected:\n");
2322                 print_regdomain_info(rd);
2323                 return -EINVAL;
2324         }
2325
2326         request_wiphy = wiphy_idx_to_wiphy(country_ie_request->wiphy_idx);
2327         if (!request_wiphy) {
2328                 schedule_delayed_work(&reg_timeout, 0);
2329                 return -ENODEV;
2330         }
2331
2332         if (country_ie_request->intersect)
2333                 return -EINVAL;
2334
2335         reset_regdomains(false, rd);
2336         return 0;
2337 }
2338
2339 /*
2340  * Use this call to set the current regulatory domain. Conflicts with
2341  * multiple drivers can be ironed out later. Caller must've already
2342  * kmalloc'd the rd structure.
2343  */
2344 int set_regdom(const struct ieee80211_regdomain *rd)
2345 {
2346         struct regulatory_request *lr;
2347         int r;
2348
2349         if (!reg_is_valid_request(rd->alpha2)) {
2350                 kfree(rd);
2351                 return -EINVAL;
2352         }
2353
2354         lr = get_last_request();
2355
2356         /* Note that this doesn't update the wiphys, this is done below */
2357         switch (lr->initiator) {
2358         case NL80211_REGDOM_SET_BY_CORE:
2359                 r = reg_set_rd_core(rd);
2360                 break;
2361         case NL80211_REGDOM_SET_BY_USER:
2362                 r = reg_set_rd_user(rd, lr);
2363                 break;
2364         case NL80211_REGDOM_SET_BY_DRIVER:
2365                 r = reg_set_rd_driver(rd, lr);
2366                 break;
2367         case NL80211_REGDOM_SET_BY_COUNTRY_IE:
2368                 r = reg_set_rd_country_ie(rd, lr);
2369                 break;
2370         default:
2371                 WARN(1, "invalid initiator %d\n", lr->initiator);
2372                 return -EINVAL;
2373         }
2374
2375         if (r) {
2376                 if (r == -EALREADY)
2377                         reg_set_request_processed();
2378
2379                 kfree(rd);
2380                 return r;
2381         }
2382
2383         /* This would make this whole thing pointless */
2384         if (WARN_ON(!lr->intersect && rd != get_cfg80211_regdom()))
2385                 return -EINVAL;
2386
2387         /* update all wiphys now with the new established regulatory domain */
2388         update_all_wiphy_regulatory(lr->initiator);
2389
2390         print_regdomain(get_cfg80211_regdom());
2391
2392         nl80211_send_reg_change_event(lr);
2393
2394         reg_set_request_processed();
2395
2396         return 0;
2397 }
2398
2399 int reg_device_uevent(struct device *dev, struct kobj_uevent_env *env)
2400 {
2401         struct regulatory_request *lr;
2402         u8 alpha2[2];
2403         bool add = false;
2404
2405         rcu_read_lock();
2406         lr = get_last_request();
2407         if (lr && !lr->processed) {
2408                 memcpy(alpha2, lr->alpha2, 2);
2409                 add = true;
2410         }
2411         rcu_read_unlock();
2412
2413         if (add)
2414                 return add_uevent_var(env, "COUNTRY=%c%c",
2415                                       alpha2[0], alpha2[1]);
2416         return 0;
2417 }
2418
2419 void wiphy_regulatory_register(struct wiphy *wiphy)
2420 {
2421         struct regulatory_request *lr;
2422
2423         if (!reg_dev_ignore_cell_hint(wiphy))
2424                 reg_num_devs_support_basehint++;
2425
2426         lr = get_last_request();
2427         wiphy_update_regulatory(wiphy, lr->initiator);
2428 }
2429
2430 void wiphy_regulatory_deregister(struct wiphy *wiphy)
2431 {
2432         struct wiphy *request_wiphy = NULL;
2433         struct regulatory_request *lr;
2434
2435         lr = get_last_request();
2436
2437         if (!reg_dev_ignore_cell_hint(wiphy))
2438                 reg_num_devs_support_basehint--;
2439
2440         rcu_free_regdom(get_wiphy_regdom(wiphy));
2441         rcu_assign_pointer(wiphy->regd, NULL);
2442
2443         if (lr)
2444                 request_wiphy = wiphy_idx_to_wiphy(lr->wiphy_idx);
2445
2446         if (!request_wiphy || request_wiphy != wiphy)
2447                 return;
2448
2449         lr->wiphy_idx = WIPHY_IDX_INVALID;
2450         lr->country_ie_env = ENVIRON_ANY;
2451 }
2452
2453 static void reg_timeout_work(struct work_struct *work)
2454 {
2455         REG_DBG_PRINT("Timeout while waiting for CRDA to reply, restoring regulatory settings\n");
2456         rtnl_lock();
2457         restore_regulatory_settings(true);
2458         rtnl_unlock();
2459 }
2460
2461 int __init regulatory_init(void)
2462 {
2463         int err = 0;
2464
2465         reg_pdev = platform_device_register_simple("regulatory", 0, NULL, 0);
2466         if (IS_ERR(reg_pdev))
2467                 return PTR_ERR(reg_pdev);
2468
2469         reg_pdev->dev.type = &reg_device_type;
2470
2471         spin_lock_init(&reg_requests_lock);
2472         spin_lock_init(&reg_pending_beacons_lock);
2473
2474         reg_regdb_size_check();
2475
2476         rcu_assign_pointer(cfg80211_regdomain, cfg80211_world_regdom);
2477
2478         user_alpha2[0] = '9';
2479         user_alpha2[1] = '7';
2480
2481         /* We always try to get an update for the static regdomain */
2482         err = regulatory_hint_core(cfg80211_world_regdom->alpha2);
2483         if (err) {
2484                 if (err == -ENOMEM)
2485                         return err;
2486                 /*
2487                  * N.B. kobject_uevent_env() can fail mainly for when we're out
2488                  * memory which is handled and propagated appropriately above
2489                  * but it can also fail during a netlink_broadcast() or during
2490                  * early boot for call_usermodehelper(). For now treat these
2491                  * errors as non-fatal.
2492                  */
2493                 pr_err("kobject_uevent_env() was unable to call CRDA during init\n");
2494         }
2495
2496         /*
2497          * Finally, if the user set the module parameter treat it
2498          * as a user hint.
2499          */
2500         if (!is_world_regdom(ieee80211_regdom))
2501                 regulatory_hint_user(ieee80211_regdom,
2502                                      NL80211_USER_REG_HINT_USER);
2503
2504         return 0;
2505 }
2506
2507 void regulatory_exit(void)
2508 {
2509         struct regulatory_request *reg_request, *tmp;
2510         struct reg_beacon *reg_beacon, *btmp;
2511
2512         cancel_work_sync(&reg_work);
2513         cancel_delayed_work_sync(&reg_timeout);
2514
2515         /* Lock to suppress warnings */
2516         rtnl_lock();
2517         reset_regdomains(true, NULL);
2518         rtnl_unlock();
2519
2520         dev_set_uevent_suppress(&reg_pdev->dev, true);
2521
2522         platform_device_unregister(reg_pdev);
2523
2524         list_for_each_entry_safe(reg_beacon, btmp, &reg_pending_beacons, list) {
2525                 list_del(&reg_beacon->list);
2526                 kfree(reg_beacon);
2527         }
2528
2529         list_for_each_entry_safe(reg_beacon, btmp, &reg_beacon_list, list) {
2530                 list_del(&reg_beacon->list);
2531                 kfree(reg_beacon);
2532         }
2533
2534         list_for_each_entry_safe(reg_request, tmp, &reg_requests_list, list) {
2535                 list_del(&reg_request->list);
2536                 kfree(reg_request);
2537         }
2538 }