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 /* Receipt of information from last regulatory request */
  85 static struct regulatory_request __rcu *last_request =
  86         (void __rcu *)&core_request_world;
  87
  88 /* To trigger userspace events */
  89 static struct platform_device *reg_pdev;
  90
  91 static struct device_type reg_device_type = {
  92         .uevent = reg_device_uevent,
  93 };
  94
  95 /*
  96  * Central wireless core regulatory domains, we only need two,
  97  * the current one and a world regulatory domain in case we have no
  98  * information to give us an alpha2.
  99  */
 100 const struct ieee80211_regdomain __rcu *cfg80211_regdomain;
 101
 102 /*
 103  * Protects static reg.c components:
 104  *      - cfg80211_regdomain (if not used with RCU)
 105  *      - cfg80211_world_regdom
 106  *      - last_request (if not used with RCU)
 107  *      - reg_num_devs_support_basehint
 108  */
 109 static DEFINE_MUTEX(reg_mutex);
 110
 111 /*
 112  * Number of devices that registered to the core
 113  * that support cellular base station regulatory hints
 114  */
 115 static int reg_num_devs_support_basehint;
 116
 117 static inline void assert_reg_lock(void)
 118 {
 119         lockdep_assert_held(&reg_mutex);
 120 }
 121
 122 static const struct ieee80211_regdomain *get_cfg80211_regdom(void)
 123 {
 124         return rcu_dereference_protected(cfg80211_regdomain,
 125                                          lockdep_is_held(&reg_mutex));
 126 }
 127
 128 static const struct ieee80211_regdomain *get_wiphy_regdom(struct wiphy *wiphy)
 129 {
 130         return rcu_dereference_protected(wiphy->regd,
 131                                          lockdep_is_held(&reg_mutex));
 132 }
 133
 134 static void rcu_free_regdom(const struct ieee80211_regdomain *r)
 135 {
 136         if (!r)
 137                 return;
 138         kfree_rcu((struct ieee80211_regdomain *)r, rcu_head);
 139 }
 140
 141 static struct regulatory_request *get_last_request(void)
 142 {
 143         return rcu_dereference_check(last_request,
 144                                      lockdep_is_held(&reg_mutex));
 145 }
 146
 147 /* Used to queue up regulatory hints */
 148 static LIST_HEAD(reg_requests_list);
 149 static spinlock_t reg_requests_lock;
 150
 151 /* Used to queue up beacon hints for review */
 152 static LIST_HEAD(reg_pending_beacons);
 153 static spinlock_t reg_pending_beacons_lock;
 154
 155 /* Used to keep track of processed beacon hints */
 156 static LIST_HEAD(reg_beacon_list);
 157
 158 struct reg_beacon {
 159         struct list_head list;
 160         struct ieee80211_channel chan;
 161 };
 162
 163 static void reg_todo(struct work_struct *work);
 164 static DECLARE_WORK(reg_work, reg_todo);
 165
 166 static void reg_timeout_work(struct work_struct *work);
 167 static DECLARE_DELAYED_WORK(reg_timeout, reg_timeout_work);
 168
 169 /* We keep a static world regulatory domain in case of the absence of CRDA */
 170 static const struct ieee80211_regdomain world_regdom = {
 171         .n_reg_rules = 6,
 172         .alpha2 =  "00",
 173         .reg_rules = {
 174                 /* IEEE 802.11b/g, channels 1..11 */
 175                 REG_RULE(2412-10, 2462+10, 40, 6, 20, 0),
 176                 /* IEEE 802.11b/g, channels 12..13. */
 177                 REG_RULE(2467-10, 2472+10, 40, 6, 20,
 178                         NL80211_RRF_PASSIVE_SCAN |
 179                         NL80211_RRF_NO_IBSS),
 180                 /* IEEE 802.11 channel 14 - Only JP enables
 181                  * this and for 802.11b only */
 182                 REG_RULE(2484-10, 2484+10, 20, 6, 20,
 183                         NL80211_RRF_PASSIVE_SCAN |
 184                         NL80211_RRF_NO_IBSS |
 185                         NL80211_RRF_NO_OFDM),
 186                 /* IEEE 802.11a, channel 36..48 */
 187                 REG_RULE(5180-10, 5240+10, 40, 6, 20,
 188                         NL80211_RRF_PASSIVE_SCAN |
 189                         NL80211_RRF_NO_IBSS),
 190
 191                 /* NB: 5260 MHz - 5700 MHz requies DFS */
 192
 193                 /* IEEE 802.11a, channel 149..165 */
 194                 REG_RULE(5745-10, 5825+10, 40, 6, 20,
 195                         NL80211_RRF_PASSIVE_SCAN |
 196                         NL80211_RRF_NO_IBSS),
 197
 198                 /* IEEE 802.11ad (60gHz), channels 1..3 */
 199                 REG_RULE(56160+2160*1-1080, 56160+2160*3+1080, 2160, 0, 0, 0),
 200         }
 201 };
 202
 203 static const struct ieee80211_regdomain *cfg80211_world_regdom =
 204         &world_regdom;
 205
 206 static char *ieee80211_regdom = "00";
 207 static char user_alpha2[2];
 208
 209 module_param(ieee80211_regdom, charp, 0444);
 210 MODULE_PARM_DESC(ieee80211_regdom, "IEEE 802.11 regulatory domain code");
 211
 212 static void reset_regdomains(bool full_reset,
 213                              const struct ieee80211_regdomain *new_regdom)
 214 {
 215         const struct ieee80211_regdomain *r;
 216         struct regulatory_request *lr;
 217
 218         assert_reg_lock();
 219
 220         r = get_cfg80211_regdom();
 221
 222         /* avoid freeing static information or freeing something twice */
 223         if (r == cfg80211_world_regdom)
 224                 r = NULL;
 225         if (cfg80211_world_regdom == &world_regdom)
 226                 cfg80211_world_regdom = NULL;
 227         if (r == &world_regdom)
 228                 r = NULL;
 229
 230         rcu_free_regdom(r);
 231         rcu_free_regdom(cfg80211_world_regdom);
 232
 233         cfg80211_world_regdom = &world_regdom;
 234         rcu_assign_pointer(cfg80211_regdomain, new_regdom);
 235
 236         if (!full_reset)
 237                 return;
 238
 239         lr = get_last_request();
 240         if (lr != &core_request_world && lr)
 241                 kfree_rcu(lr, rcu_head);
 242         rcu_assign_pointer(last_request, &core_request_world);
 243 }
 244
 245 /*
 246  * Dynamic world regulatory domain requested by the wireless
 247  * core upon initialization
 248  */
 249 static void update_world_regdomain(const struct ieee80211_regdomain *rd)
 250 {
 251         struct regulatory_request *lr;
 252
 253         lr = get_last_request();
 254
 255         WARN_ON(!lr);
 256
 257         reset_regdomains(false, rd);
 258
 259         cfg80211_world_regdom = rd;
 260 }
 261
 262 bool is_world_regdom(const char *alpha2)
 263 {
 264         if (!alpha2)
 265                 return false;
 266         return alpha2[0] == '0' && alpha2[1] == '0';
 267 }
 268
 269 static bool is_alpha2_set(const char *alpha2)
 270 {
 271         if (!alpha2)
 272                 return false;
 273         return alpha2[0] && alpha2[1];
 274 }
 275
 276 static bool is_unknown_alpha2(const char *alpha2)
 277 {
 278         if (!alpha2)
 279                 return false;
 280         /*
 281          * Special case where regulatory domain was built by driver
 282          * but a specific alpha2 cannot be determined
 283          */
 284         return alpha2[0] == '9' && alpha2[1] == '9';
 285 }
 286
 287 static bool is_intersected_alpha2(const char *alpha2)
 288 {
 289         if (!alpha2)
 290                 return false;
 291         /*
 292          * Special case where regulatory domain is the
 293          * result of an intersection between two regulatory domain
 294          * structures
 295          */
 296         return alpha2[0] == '9' && alpha2[1] == '8';
 297 }
 298
 299 static bool is_an_alpha2(const char *alpha2)
 300 {
 301         if (!alpha2)
 302                 return false;
 303         return isalpha(alpha2[0]) && isalpha(alpha2[1]);
 304 }
 305
 306 static bool alpha2_equal(const char *alpha2_x, const char *alpha2_y)
 307 {
 308         if (!alpha2_x || !alpha2_y)
 309                 return false;
 310         return alpha2_x[0] == alpha2_y[0] && alpha2_x[1] == alpha2_y[1];
 311 }
 312
 313 static bool regdom_changes(const char *alpha2)
 314 {
 315         const struct ieee80211_regdomain *r = get_cfg80211_regdom();
 316
 317         if (!r)
 318                 return true;
 319         return !alpha2_equal(r->alpha2, alpha2);
 320 }
 321
 322 /*
 323  * The NL80211_REGDOM_SET_BY_USER regdom alpha2 is cached, this lets
 324  * you know if a valid regulatory hint with NL80211_REGDOM_SET_BY_USER
 325  * has ever been issued.
 326  */
 327 static bool is_user_regdom_saved(void)
 328 {
 329         if (user_alpha2[0] == '9' && user_alpha2[1] == '7')
 330                 return false;
 331
 332         /* This would indicate a mistake on the design */
 333         if (WARN(!is_world_regdom(user_alpha2) && !is_an_alpha2(user_alpha2),
 334                  "Unexpected user alpha2: %c%c\n",
 335                  user_alpha2[0], user_alpha2[1]))
 336                 return false;
 337
 338         return true;
 339 }
 340
 341 static const struct ieee80211_regdomain *
 342 reg_copy_regd(const struct ieee80211_regdomain *src_regd)
 343 {
 344         struct ieee80211_regdomain *regd;
 345         int size_of_regd;
 346         unsigned int i;
 347
 348         size_of_regd =
 349                 sizeof(struct ieee80211_regdomain) +
 350                 src_regd->n_reg_rules * sizeof(struct ieee80211_reg_rule);
 351
 352         regd = kzalloc(size_of_regd, GFP_KERNEL);
 353         if (!regd)
 354                 return ERR_PTR(-ENOMEM);
 355
 356         memcpy(regd, src_regd, sizeof(struct ieee80211_regdomain));
 357
 358         for (i = 0; i < src_regd->n_reg_rules; i++)
 359                 memcpy(&regd->reg_rules[i], &src_regd->reg_rules[i],
 360                        sizeof(struct ieee80211_reg_rule));
 361
 362         return regd;
 363 }
 364
 365 #ifdef CONFIG_CFG80211_INTERNAL_REGDB
 366 struct reg_regdb_search_request {
 367         char alpha2[2];
 368         struct list_head list;
 369 };
 370
 371 static LIST_HEAD(reg_regdb_search_list);
 372 static DEFINE_MUTEX(reg_regdb_search_mutex);
 373
 374 static void reg_regdb_search(struct work_struct *work)
 375 {
 376         struct reg_regdb_search_request *request;
 377         const struct ieee80211_regdomain *curdom, *regdom = NULL;
 378         int i;
 379
 380         mutex_lock(&cfg80211_mutex);
 381
 382         mutex_lock(&reg_regdb_search_mutex);
 383         while (!list_empty(&reg_regdb_search_list)) {
 384                 request = list_first_entry(&reg_regdb_search_list,
 385                                            struct reg_regdb_search_request,
 386                                            list);
 387                 list_del(&request->list);
 388
 389                 for (i = 0; i < reg_regdb_size; i++) {
 390                         curdom = reg_regdb[i];
 391
 392                         if (alpha2_equal(request->alpha2, curdom->alpha2)) {
 393                                 regdom = reg_copy_regd(curdom);
 394                                 break;
 395                         }
 396                 }
 397
 398                 kfree(request);
 399         }
 400         mutex_unlock(&reg_regdb_search_mutex);
 401
 402         if (!IS_ERR_OR_NULL(regdom))
 403                 set_regdom(regdom);
 404
 405         mutex_unlock(&cfg80211_mutex);
 406 }
 407
 408 static DECLARE_WORK(reg_regdb_work, reg_regdb_search);
 409
 410 static void reg_regdb_query(const char *alpha2)
 411 {
 412         struct reg_regdb_search_request *request;
 413
 414         if (!alpha2)
 415                 return;
 416
 417         request = kzalloc(sizeof(struct reg_regdb_search_request), GFP_KERNEL);
 418         if (!request)
 419                 return;
 420
 421         memcpy(request->alpha2, alpha2, 2);
 422
 423         mutex_lock(&reg_regdb_search_mutex);
 424         list_add_tail(&request->list, &reg_regdb_search_list);
 425         mutex_unlock(&reg_regdb_search_mutex);
 426
 427         schedule_work(&reg_regdb_work);
 428 }
 429
 430 /* Feel free to add any other sanity checks here */
 431 static void reg_regdb_size_check(void)
 432 {
 433         /* We should ideally BUILD_BUG_ON() but then random builds would fail */
 434         WARN_ONCE(!reg_regdb_size, "db.txt is empty, you should update it...");
 435 }
 436 #else
 437 static inline void reg_regdb_size_check(void) {}
 438 static inline void reg_regdb_query(const char *alpha2) {}
 439 #endif /* CONFIG_CFG80211_INTERNAL_REGDB */
 440
 441 /*
 442  * This lets us keep regulatory code which is updated on a regulatory
 443  * basis in userspace. Country information is filled in by
 444  * reg_device_uevent
 445  */
 446 static int call_crda(const char *alpha2)
 447 {
 448         if (!is_world_regdom((char *) alpha2))
 449                 pr_info("Calling CRDA for country: %c%c\n",
 450                         alpha2[0], alpha2[1]);
 451         else
 452                 pr_info("Calling CRDA to update world regulatory domain\n");
 453
 454         /* query internal regulatory database (if it exists) */
 455         reg_regdb_query(alpha2);
 456
 457         return kobject_uevent(&reg_pdev->dev.kobj, KOBJ_CHANGE);
 458 }
 459
 460 static bool reg_is_valid_request(const char *alpha2)
 461 {
 462         struct regulatory_request *lr = get_last_request();
 463
 464         if (!lr || lr->processed)
 465                 return false;
 466
 467         return alpha2_equal(lr->alpha2, alpha2);
 468 }
 469
 470 /* Sanity check on a regulatory rule */
 471 static bool is_valid_reg_rule(const struct ieee80211_reg_rule *rule)
 472 {
 473         const struct ieee80211_freq_range *freq_range = &rule->freq_range;
 474         u32 freq_diff;
 475
 476         if (freq_range->start_freq_khz <= 0 || freq_range->end_freq_khz <= 0)
 477                 return false;
 478
 479         if (freq_range->start_freq_khz > freq_range->end_freq_khz)
 480                 return false;
 481
 482         freq_diff = freq_range->end_freq_khz - freq_range->start_freq_khz;
 483
 484         if (freq_range->end_freq_khz <= freq_range->start_freq_khz ||
 485             freq_range->max_bandwidth_khz > freq_diff)
 486                 return false;
 487
 488         return true;
 489 }
 490
 491 static bool is_valid_rd(const struct ieee80211_regdomain *rd)
 492 {
 493         const struct ieee80211_reg_rule *reg_rule = NULL;
 494         unsigned int i;
 495
 496         if (!rd->n_reg_rules)
 497                 return false;
 498
 499         if (WARN_ON(rd->n_reg_rules > NL80211_MAX_SUPP_REG_RULES))
 500                 return false;
 501
 502         for (i = 0; i < rd->n_reg_rules; i++) {
 503                 reg_rule = &rd->reg_rules[i];
 504                 if (!is_valid_reg_rule(reg_rule))
 505                         return false;
 506         }
 507
 508         return true;
 509 }
 510
 511 static bool reg_does_bw_fit(const struct ieee80211_freq_range *freq_range,
 512                             u32 center_freq_khz, u32 bw_khz)
 513 {
 514         u32 start_freq_khz, end_freq_khz;
 515
 516         start_freq_khz = center_freq_khz - (bw_khz/2);
 517         end_freq_khz = center_freq_khz + (bw_khz/2);
 518
 519         if (start_freq_khz >= freq_range->start_freq_khz &&
 520             end_freq_khz <= freq_range->end_freq_khz)
 521                 return true;
 522
 523         return false;
 524 }
 525
 526 /**
 527  * freq_in_rule_band - tells us if a frequency is in a frequency band
 528  * @freq_range: frequency rule we want to query
 529  * @freq_khz: frequency we are inquiring about
 530  *
 531  * This lets us know if a specific frequency rule is or is not relevant to
 532  * a specific frequency's band. Bands are device specific and artificial
 533  * definitions (the "2.4 GHz band", the "5 GHz band" and the "60GHz band"),
 534  * however it is safe for now to assume that a frequency rule should not be
 535  * part of a frequency's band if the start freq or end freq are off by more
 536  * than 2 GHz for the 2.4 and 5 GHz bands, and by more than 10 GHz for the
 537  * 60 GHz band.
 538  * This resolution can be lowered and should be considered as we add
 539  * regulatory rule support for other "bands".
 540  **/
 541 static bool freq_in_rule_band(const struct ieee80211_freq_range *freq_range,
 542                               u32 freq_khz)
 543 {
 544 #define ONE_GHZ_IN_KHZ  1000000
 545         /*
 546          * From 802.11ad: directional multi-gigabit (DMG):
 547          * Pertaining to operation in a frequency band containing a channel
 548          * with the Channel starting frequency above 45 GHz.
 549          */
 550         u32 limit = freq_khz > 45 * ONE_GHZ_IN_KHZ ?
 551                         10 * ONE_GHZ_IN_KHZ : 2 * ONE_GHZ_IN_KHZ;
 552         if (abs(freq_khz - freq_range->start_freq_khz) <= limit)
 553                 return true;
 554         if (abs(freq_khz - freq_range->end_freq_khz) <= limit)
 555                 return true;
 556         return false;
 557 #undef ONE_GHZ_IN_KHZ
 558 }
 559
 560 /*
 561  * Helper for regdom_intersect(), this does the real
 562  * mathematical intersection fun
 563  */
 564 static int reg_rules_intersect(const struct ieee80211_reg_rule *rule1,
 565                                const struct ieee80211_reg_rule *rule2,
 566                                struct ieee80211_reg_rule *intersected_rule)
 567 {
 568         const struct ieee80211_freq_range *freq_range1, *freq_range2;
 569         struct ieee80211_freq_range *freq_range;
 570         const struct ieee80211_power_rule *power_rule1, *power_rule2;
 571         struct ieee80211_power_rule *power_rule;
 572         u32 freq_diff;
 573
 574         freq_range1 = &rule1->freq_range;
 575         freq_range2 = &rule2->freq_range;
 576         freq_range = &intersected_rule->freq_range;
 577
 578         power_rule1 = &rule1->power_rule;
 579         power_rule2 = &rule2->power_rule;
 580         power_rule = &intersected_rule->power_rule;
 581
 582         freq_range->start_freq_khz = max(freq_range1->start_freq_khz,
 583                                          freq_range2->start_freq_khz);
 584         freq_range->end_freq_khz = min(freq_range1->end_freq_khz,
 585                                        freq_range2->end_freq_khz);
 586         freq_range->max_bandwidth_khz = min(freq_range1->max_bandwidth_khz,
 587                                             freq_range2->max_bandwidth_khz);
 588
 589         freq_diff = freq_range->end_freq_khz - freq_range->start_freq_khz;
 590         if (freq_range->max_bandwidth_khz > freq_diff)
 591                 freq_range->max_bandwidth_khz = freq_diff;
 592
 593         power_rule->max_eirp = min(power_rule1->max_eirp,
 594                 power_rule2->max_eirp);
 595         power_rule->max_antenna_gain = min(power_rule1->max_antenna_gain,
 596                 power_rule2->max_antenna_gain);
 597
 598         intersected_rule->flags = rule1->flags | rule2->flags;
 599
 600         if (!is_valid_reg_rule(intersected_rule))
 601                 return -EINVAL;
 602
 603         return 0;
 604 }
 605
 606 /**
 607  * regdom_intersect - do the intersection between two regulatory domains
 608  * @rd1: first regulatory domain
 609  * @rd2: second regulatory domain
 610  *
 611  * Use this function to get the intersection between two regulatory domains.
 612  * Once completed we will mark the alpha2 for the rd as intersected, "98",
 613  * as no one single alpha2 can represent this regulatory domain.
 614  *
 615  * Returns a pointer to the regulatory domain structure which will hold the
 616  * resulting intersection of rules between rd1 and rd2. We will
 617  * kzalloc() this structure for you.
 618  */
 619 static struct ieee80211_regdomain *
 620 regdom_intersect(const struct ieee80211_regdomain *rd1,
 621                  const struct ieee80211_regdomain *rd2)
 622 {
 623         int r, size_of_regd;
 624         unsigned int x, y;
 625         unsigned int num_rules = 0, rule_idx = 0;
 626         const struct ieee80211_reg_rule *rule1, *rule2;
 627         struct ieee80211_reg_rule *intersected_rule;
 628         struct ieee80211_regdomain *rd;
 629         /* This is just a dummy holder to help us count */
 630         struct ieee80211_reg_rule dummy_rule;
 631
 632         if (!rd1 || !rd2)
 633                 return NULL;
 634
 635         /*
 636          * First we get a count of the rules we'll need, then we actually
 637          * build them. This is to so we can malloc() and free() a
 638          * regdomain once. The reason we use reg_rules_intersect() here
 639          * is it will return -EINVAL if the rule computed makes no sense.
 640          * All rules that do check out OK are valid.
 641          */
 642
 643         for (x = 0; x < rd1->n_reg_rules; x++) {
 644                 rule1 = &rd1->reg_rules[x];
 645                 for (y = 0; y < rd2->n_reg_rules; y++) {
 646                         rule2 = &rd2->reg_rules[y];
 647                         if (!reg_rules_intersect(rule1, rule2, &dummy_rule))
 648                                 num_rules++;
 649                 }
 650         }
 651
 652         if (!num_rules)
 653                 return NULL;
 654
 655         size_of_regd = sizeof(struct ieee80211_regdomain) +
 656                        num_rules * sizeof(struct ieee80211_reg_rule);
 657
 658         rd = kzalloc(size_of_regd, GFP_KERNEL);
 659         if (!rd)
 660                 return NULL;
 661
 662         for (x = 0; x < rd1->n_reg_rules && rule_idx < num_rules; x++) {
 663                 rule1 = &rd1->reg_rules[x];
 664                 for (y = 0; y < rd2->n_reg_rules && rule_idx < num_rules; y++) {
 665                         rule2 = &rd2->reg_rules[y];
 666                         /*
 667                          * This time around instead of using the stack lets
 668                          * write to the target rule directly saving ourselves
 669                          * a memcpy()
 670                          */
 671                         intersected_rule = &rd->reg_rules[rule_idx];
 672                         r = reg_rules_intersect(rule1, rule2, intersected_rule);
 673                         /*
 674                          * No need to memset here the intersected rule here as
 675                          * we're not using the stack anymore
 676                          */
 677                         if (r)
 678                                 continue;
 679                         rule_idx++;
 680                 }
 681         }
 682
 683         if (rule_idx != num_rules) {
 684                 kfree(rd);
 685                 return NULL;
 686         }
 687
 688         rd->n_reg_rules = num_rules;
 689         rd->alpha2[0] = '9';
 690         rd->alpha2[1] = '8';
 691
 692         return rd;
 693 }
 694
 695 /*
 696  * XXX: add support for the rest of enum nl80211_reg_rule_flags, we may
 697  * want to just have the channel structure use these
 698  */
 699 static u32 map_regdom_flags(u32 rd_flags)
 700 {
 701         u32 channel_flags = 0;
 702         if (rd_flags & NL80211_RRF_PASSIVE_SCAN)
 703                 channel_flags |= IEEE80211_CHAN_PASSIVE_SCAN;
 704         if (rd_flags & NL80211_RRF_NO_IBSS)
 705                 channel_flags |= IEEE80211_CHAN_NO_IBSS;
 706         if (rd_flags & NL80211_RRF_DFS)
 707                 channel_flags |= IEEE80211_CHAN_RADAR;
 708         if (rd_flags & NL80211_RRF_NO_OFDM)
 709                 channel_flags |= IEEE80211_CHAN_NO_OFDM;
 710         return channel_flags;
 711 }
 712
 713 static const struct ieee80211_reg_rule *
 714 freq_reg_info_regd(struct wiphy *wiphy, u32 center_freq,
 715                    const struct ieee80211_regdomain *regd)
 716 {
 717         int i;
 718         bool band_rule_found = false;
 719         bool bw_fits = false;
 720
 721         if (!regd)
 722                 return ERR_PTR(-EINVAL);
 723
 724         for (i = 0; i < regd->n_reg_rules; i++) {
 725                 const struct ieee80211_reg_rule *rr;
 726                 const struct ieee80211_freq_range *fr = NULL;
 727
 728                 rr = &regd->reg_rules[i];
 729                 fr = &rr->freq_range;
 730
 731                 /*
 732                  * We only need to know if one frequency rule was
 733                  * was in center_freq's band, that's enough, so lets
 734                  * not overwrite it once found
 735                  */
 736                 if (!band_rule_found)
 737                         band_rule_found = freq_in_rule_band(fr, center_freq);
 738
 739                 bw_fits = reg_does_bw_fit(fr, center_freq, MHZ_TO_KHZ(20));
 740
 741                 if (band_rule_found && bw_fits)
 742                         return rr;
 743         }
 744
 745         if (!band_rule_found)
 746                 return ERR_PTR(-ERANGE);
 747
 748         return ERR_PTR(-EINVAL);
 749 }
 750
 751 const struct ieee80211_reg_rule *freq_reg_info(struct wiphy *wiphy,
 752                                                u32 center_freq)
 753 {
 754         const struct ieee80211_regdomain *regd;
 755         struct regulatory_request *lr = get_last_request();
 756
 757         /*
 758          * Follow the driver's regulatory domain, if present, unless a country
 759          * IE has been processed or a user wants to help complaince further
 760          */
 761         if (lr->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE &&
 762             lr->initiator != NL80211_REGDOM_SET_BY_USER &&
 763             wiphy->regd)
 764                 regd = get_wiphy_regdom(wiphy);
 765         else
 766                 regd = get_cfg80211_regdom();
 767
 768         return freq_reg_info_regd(wiphy, center_freq, regd);
 769 }
 770 EXPORT_SYMBOL(freq_reg_info);
 771
 772 #ifdef CONFIG_CFG80211_REG_DEBUG
 773 static const char *reg_initiator_name(enum nl80211_reg_initiator initiator)
 774 {
 775         switch (initiator) {
 776         case NL80211_REGDOM_SET_BY_CORE:
 777                 return "Set by core";
 778         case NL80211_REGDOM_SET_BY_USER:
 779                 return "Set by user";
 780         case NL80211_REGDOM_SET_BY_DRIVER:
 781                 return "Set by driver";
 782         case NL80211_REGDOM_SET_BY_COUNTRY_IE:
 783                 return "Set by country IE";
 784         default:
 785                 WARN_ON(1);
 786                 return "Set by bug";
 787         }
 788 }
 789
 790 static void chan_reg_rule_print_dbg(struct ieee80211_channel *chan,
 791                                     const struct ieee80211_reg_rule *reg_rule)
 792 {
 793         const struct ieee80211_power_rule *power_rule;
 794         const struct ieee80211_freq_range *freq_range;
 795         char max_antenna_gain[32];
 796
 797         power_rule = &reg_rule->power_rule;
 798         freq_range = &reg_rule->freq_range;
 799
 800         if (!power_rule->max_antenna_gain)
 801                 snprintf(max_antenna_gain, 32, "N/A");
 802         else
 803                 snprintf(max_antenna_gain, 32, "%d", power_rule->max_antenna_gain);
 804
 805         REG_DBG_PRINT("Updating information on frequency %d MHz with regulatory rule:\n",
 806                       chan->center_freq);
 807
 808         REG_DBG_PRINT("%d KHz - %d KHz @ %d KHz), (%s mBi, %d mBm)\n",
 809                       freq_range->start_freq_khz, freq_range->end_freq_khz,
 810                       freq_range->max_bandwidth_khz, max_antenna_gain,
 811                       power_rule->max_eirp);
 812 }
 813 #else
 814 static void chan_reg_rule_print_dbg(struct ieee80211_channel *chan,
 815                                     const struct ieee80211_reg_rule *reg_rule)
 816 {
 817         return;
 818 }
 819 #endif
 820
 821 /*
 822  * Note that right now we assume the desired channel bandwidth
 823  * is always 20 MHz for each individual channel (HT40 uses 20 MHz
 824  * per channel, the primary and the extension channel).
 825  */
 826 static void handle_channel(struct wiphy *wiphy,
 827                            enum nl80211_reg_initiator initiator,
 828                            struct ieee80211_channel *chan)
 829 {
 830         u32 flags, bw_flags = 0;
 831         const struct ieee80211_reg_rule *reg_rule = NULL;
 832         const struct ieee80211_power_rule *power_rule = NULL;
 833         const struct ieee80211_freq_range *freq_range = NULL;
 834         struct wiphy *request_wiphy = NULL;
 835         struct regulatory_request *lr = get_last_request();
 836
 837         request_wiphy = wiphy_idx_to_wiphy(lr->wiphy_idx);
 838
 839         flags = chan->orig_flags;
 840
 841         reg_rule = freq_reg_info(wiphy, MHZ_TO_KHZ(chan->center_freq));
 842         if (IS_ERR(reg_rule)) {
 843                 /*
 844                  * We will disable all channels that do not match our
 845                  * received regulatory rule unless the hint is coming
 846                  * from a Country IE and the Country IE had no information
 847                  * about a band. The IEEE 802.11 spec allows for an AP
 848                  * to send only a subset of the regulatory rules allowed,
 849                  * so an AP in the US that only supports 2.4 GHz may only send
 850                  * a country IE with information for the 2.4 GHz band
 851                  * while 5 GHz is still supported.
 852                  */
 853                 if (initiator == NL80211_REGDOM_SET_BY_COUNTRY_IE &&
 854                     PTR_ERR(reg_rule) == -ERANGE)
 855                         return;
 856
 857                 REG_DBG_PRINT("Disabling freq %d MHz\n", chan->center_freq);
 858                 chan->flags = IEEE80211_CHAN_DISABLED;
 859                 return;
 860         }
 861
 862         chan_reg_rule_print_dbg(chan, reg_rule);
 863
 864         power_rule = &reg_rule->power_rule;
 865         freq_range = &reg_rule->freq_range;
 866
 867         if (freq_range->max_bandwidth_khz < MHZ_TO_KHZ(40))
 868                 bw_flags = IEEE80211_CHAN_NO_HT40;
 869
 870         if (lr->initiator == NL80211_REGDOM_SET_BY_DRIVER &&
 871             request_wiphy && request_wiphy == wiphy &&
 872             request_wiphy->flags & WIPHY_FLAG_STRICT_REGULATORY) {
 873                 /*
 874                  * This guarantees the driver's requested regulatory domain
 875                  * will always be used as a base for further regulatory
 876                  * settings
 877                  */
 878                 chan->flags = chan->orig_flags =
 879                         map_regdom_flags(reg_rule->flags) | bw_flags;
 880                 chan->max_antenna_gain = chan->orig_mag =
 881                         (int) MBI_TO_DBI(power_rule->max_antenna_gain);
 882                 chan->max_reg_power = chan->max_power = chan->orig_mpwr =
 883                         (int) MBM_TO_DBM(power_rule->max_eirp);
 884                 return;
 885         }
 886
 887         chan->beacon_found = false;
 888         chan->flags = flags | bw_flags | map_regdom_flags(reg_rule->flags);
 889         chan->max_antenna_gain =
 890                 min_t(int, chan->orig_mag,
 891                       MBI_TO_DBI(power_rule->max_antenna_gain));
 892         chan->max_reg_power = (int) MBM_TO_DBM(power_rule->max_eirp);
 893         if (chan->orig_mpwr) {
 894                 /*
 895                  * Devices that have their own custom regulatory domain
 896                  * but also use WIPHY_FLAG_STRICT_REGULATORY will follow the
 897                  * passed country IE power settings.
 898                  */
 899                 if (initiator == NL80211_REGDOM_SET_BY_COUNTRY_IE &&
 900                     wiphy->flags & WIPHY_FLAG_CUSTOM_REGULATORY &&
 901                     wiphy->flags & WIPHY_FLAG_STRICT_REGULATORY)
 902                         chan->max_power = chan->max_reg_power;
 903                 else
 904                         chan->max_power = min(chan->orig_mpwr,
 905                                               chan->max_reg_power);
 906         } else
 907                 chan->max_power = chan->max_reg_power;
 908 }
 909
 910 static void handle_band(struct wiphy *wiphy,
 911                         enum nl80211_reg_initiator initiator,
 912                         struct ieee80211_supported_band *sband)
 913 {
 914         unsigned int i;
 915
 916         if (!sband)
 917                 return;
 918
 919         for (i = 0; i < sband->n_channels; i++)
 920                 handle_channel(wiphy, initiator, &sband->channels[i]);
 921 }
 922
 923 static bool reg_request_cell_base(struct regulatory_request *request)
 924 {
 925         if (request->initiator != NL80211_REGDOM_SET_BY_USER)
 926                 return false;
 927         return request->user_reg_hint_type == NL80211_USER_REG_HINT_CELL_BASE;
 928 }
 929
 930 bool reg_last_request_cell_base(void)
 931 {
 932         bool val;
 933
 934         mutex_lock(&reg_mutex);
 935         val = reg_request_cell_base(get_last_request());
 936         mutex_unlock(&reg_mutex);
 937
 938         return val;
 939 }
 940
 941 #ifdef CONFIG_CFG80211_CERTIFICATION_ONUS
 942 /* Core specific check */
 943 static enum reg_request_treatment
 944 reg_ignore_cell_hint(struct regulatory_request *pending_request)
 945 {
 946         struct regulatory_request *lr = get_last_request();
 947
 948         if (!reg_num_devs_support_basehint)
 949                 return REG_REQ_IGNORE;
 950
 951         if (reg_request_cell_base(lr) &&
 952             !regdom_changes(pending_request->alpha2))
 953                 return REG_REQ_ALREADY_SET;
 954
 955         return REG_REQ_OK;
 956 }
 957
 958 /* Device specific check */
 959 static bool reg_dev_ignore_cell_hint(struct wiphy *wiphy)
 960 {
 961         return !(wiphy->features & NL80211_FEATURE_CELL_BASE_REG_HINTS);
 962 }
 963 #else
 964 static int reg_ignore_cell_hint(struct regulatory_request *pending_request)
 965 {
 966         return REG_REQ_IGNORE;
 967 }
 968
 969 static bool reg_dev_ignore_cell_hint(struct wiphy *wiphy)
 970 {
 971         return true;
 972 }
 973 #endif
 974
 975
 976 static bool ignore_reg_update(struct wiphy *wiphy,
 977                               enum nl80211_reg_initiator initiator)
 978 {
 979         struct regulatory_request *lr = get_last_request();
 980
 981         if (!lr) {
 982                 REG_DBG_PRINT("Ignoring regulatory request %s since last_request is not set\n",
 983                               reg_initiator_name(initiator));
 984                 return true;
 985         }
 986
 987         if (initiator == NL80211_REGDOM_SET_BY_CORE &&
 988             wiphy->flags & WIPHY_FLAG_CUSTOM_REGULATORY) {
 989                 REG_DBG_PRINT("Ignoring regulatory request %s since the driver uses its own custom regulatory domain\n",
 990                               reg_initiator_name(initiator));
 991                 return true;
 992         }
 993
 994         /*
 995          * wiphy->regd will be set once the device has its own
 996          * desired regulatory domain set
 997          */
 998         if (wiphy->flags & WIPHY_FLAG_STRICT_REGULATORY && !wiphy->regd &&
 999             initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE &&
1000             !is_world_regdom(lr->alpha2)) {
1001                 REG_DBG_PRINT("Ignoring regulatory request %s since the driver requires its own regulatory domain to be set first\n",
1002                               reg_initiator_name(initiator));
1003                 return true;
1004         }
1005
1006         if (reg_request_cell_base(lr))
1007                 return reg_dev_ignore_cell_hint(wiphy);
1008
1009         return false;
1010 }
1011
1012 static bool reg_is_world_roaming(struct wiphy *wiphy)
1013 {
1014         const struct ieee80211_regdomain *cr = get_cfg80211_regdom();
1015         const struct ieee80211_regdomain *wr = get_wiphy_regdom(wiphy);
1016         struct regulatory_request *lr = get_last_request();
1017
1018         if (is_world_regdom(cr->alpha2) || (wr && is_world_regdom(wr->alpha2)))
1019                 return true;
1020
1021         if (lr && lr->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE &&
1022             wiphy->flags & WIPHY_FLAG_CUSTOM_REGULATORY)
1023                 return true;
1024
1025         return false;
1026 }
1027
1028 static void handle_reg_beacon(struct wiphy *wiphy, unsigned int chan_idx,
1029                               struct reg_beacon *reg_beacon)
1030 {
1031         struct ieee80211_supported_band *sband;
1032         struct ieee80211_channel *chan;
1033         bool channel_changed = false;
1034         struct ieee80211_channel chan_before;
1035
1036         sband = wiphy->bands[reg_beacon->chan.band];
1037         chan = &sband->channels[chan_idx];
1038
1039         if (likely(chan->center_freq != reg_beacon->chan.center_freq))
1040                 return;
1041
1042         if (chan->beacon_found)
1043                 return;
1044
1045         chan->beacon_found = true;
1046
1047         if (!reg_is_world_roaming(wiphy))
1048                 return;
1049
1050         if (wiphy->flags & WIPHY_FLAG_DISABLE_BEACON_HINTS)
1051                 return;
1052
1053         chan_before.center_freq = chan->center_freq;
1054         chan_before.flags = chan->flags;
1055
1056         if (chan->flags & IEEE80211_CHAN_PASSIVE_SCAN) {
1057                 chan->flags &= ~IEEE80211_CHAN_PASSIVE_SCAN;
1058                 channel_changed = true;
1059         }
1060
1061         if (chan->flags & IEEE80211_CHAN_NO_IBSS) {
1062                 chan->flags &= ~IEEE80211_CHAN_NO_IBSS;
1063                 channel_changed = true;
1064         }
1065
1066         if (channel_changed)
1067                 nl80211_send_beacon_hint_event(wiphy, &chan_before, chan);
1068 }
1069
1070 /*
1071  * Called when a scan on a wiphy finds a beacon on
1072  * new channel
1073  */
1074 static void wiphy_update_new_beacon(struct wiphy *wiphy,
1075                                     struct reg_beacon *reg_beacon)
1076 {
1077         unsigned int i;
1078         struct ieee80211_supported_band *sband;
1079
1080         if (!wiphy->bands[reg_beacon->chan.band])
1081                 return;
1082
1083         sband = wiphy->bands[reg_beacon->chan.band];
1084
1085         for (i = 0; i < sband->n_channels; i++)
1086                 handle_reg_beacon(wiphy, i, reg_beacon);
1087 }
1088
1089 /*
1090  * Called upon reg changes or a new wiphy is added
1091  */
1092 static void wiphy_update_beacon_reg(struct wiphy *wiphy)
1093 {
1094         unsigned int i;
1095         struct ieee80211_supported_band *sband;
1096         struct reg_beacon *reg_beacon;
1097
1098         list_for_each_entry(reg_beacon, &reg_beacon_list, list) {
1099                 if (!wiphy->bands[reg_beacon->chan.band])
1100                         continue;
1101                 sband = wiphy->bands[reg_beacon->chan.band];
1102                 for (i = 0; i < sband->n_channels; i++)
1103                         handle_reg_beacon(wiphy, i, reg_beacon);
1104         }
1105 }
1106
1107 /* Reap the advantages of previously found beacons */
1108 static void reg_process_beacons(struct wiphy *wiphy)
1109 {
1110         /*
1111          * Means we are just firing up cfg80211, so no beacons would
1112          * have been processed yet.
1113          */
1114         if (!last_request)
1115                 return;
1116         wiphy_update_beacon_reg(wiphy);
1117 }
1118
1119 static bool is_ht40_allowed(struct ieee80211_channel *chan)
1120 {
1121         if (!chan)
1122                 return false;
1123         if (chan->flags & IEEE80211_CHAN_DISABLED)
1124                 return false;
1125         /* This would happen when regulatory rules disallow HT40 completely */
1126         if ((chan->flags & IEEE80211_CHAN_NO_HT40) == IEEE80211_CHAN_NO_HT40)
1127                 return false;
1128         return true;
1129 }
1130
1131 static void reg_process_ht_flags_channel(struct wiphy *wiphy,
1132                                          struct ieee80211_channel *channel)
1133 {
1134         struct ieee80211_supported_band *sband = wiphy->bands[channel->band];
1135         struct ieee80211_channel *channel_before = NULL, *channel_after = NULL;
1136         unsigned int i;
1137
1138         if (!is_ht40_allowed(channel)) {
1139                 channel->flags |= IEEE80211_CHAN_NO_HT40;
1140                 return;
1141         }
1142
1143         /*
1144          * We need to ensure the extension channels exist to
1145          * be able to use HT40- or HT40+, this finds them (or not)
1146          */
1147         for (i = 0; i < sband->n_channels; i++) {
1148                 struct ieee80211_channel *c = &sband->channels[i];
1149
1150                 if (c->center_freq == (channel->center_freq - 20))
1151                         channel_before = c;
1152                 if (c->center_freq == (channel->center_freq + 20))
1153                         channel_after = c;
1154         }
1155
1156         /*
1157          * Please note that this assumes target bandwidth is 20 MHz,
1158          * if that ever changes we also need to change the below logic
1159          * to include that as well.
1160          */
1161         if (!is_ht40_allowed(channel_before))
1162                 channel->flags |= IEEE80211_CHAN_NO_HT40MINUS;
1163         else
1164                 channel->flags &= ~IEEE80211_CHAN_NO_HT40MINUS;
1165
1166         if (!is_ht40_allowed(channel_after))
1167                 channel->flags |= IEEE80211_CHAN_NO_HT40PLUS;
1168         else
1169                 channel->flags &= ~IEEE80211_CHAN_NO_HT40PLUS;
1170 }
1171
1172 static void reg_process_ht_flags_band(struct wiphy *wiphy,
1173                                       struct ieee80211_supported_band *sband)
1174 {
1175         unsigned int i;
1176
1177         if (!sband)
1178                 return;
1179
1180         for (i = 0; i < sband->n_channels; i++)
1181                 reg_process_ht_flags_channel(wiphy, &sband->channels[i]);
1182 }
1183
1184 static void reg_process_ht_flags(struct wiphy *wiphy)
1185 {
1186         enum ieee80211_band band;
1187
1188         if (!wiphy)
1189                 return;
1190
1191         for (band = 0; band < IEEE80211_NUM_BANDS; band++)
1192                 reg_process_ht_flags_band(wiphy, wiphy->bands[band]);
1193 }
1194
1195 static void wiphy_update_regulatory(struct wiphy *wiphy,
1196                                     enum nl80211_reg_initiator initiator)
1197 {
1198         enum ieee80211_band band;
1199         struct regulatory_request *lr = get_last_request();
1200
1201         if (ignore_reg_update(wiphy, initiator))
1202                 return;
1203
1204         lr->dfs_region = get_cfg80211_regdom()->dfs_region;
1205
1206         for (band = 0; band < IEEE80211_NUM_BANDS; band++)
1207                 handle_band(wiphy, initiator, wiphy->bands[band]);
1208
1209         reg_process_beacons(wiphy);
1210         reg_process_ht_flags(wiphy);
1211
1212         if (wiphy->reg_notifier)
1213                 wiphy->reg_notifier(wiphy, lr);
1214 }
1215
1216 static void update_all_wiphy_regulatory(enum nl80211_reg_initiator initiator)
1217 {
1218         struct cfg80211_registered_device *rdev;
1219         struct wiphy *wiphy;
1220
1221         assert_cfg80211_lock();
1222
1223         list_for_each_entry(rdev, &cfg80211_rdev_list, list) {
1224                 wiphy = &rdev->wiphy;
1225                 wiphy_update_regulatory(wiphy, initiator);
1226                 /*
1227                  * Regulatory updates set by CORE are ignored for custom
1228                  * regulatory cards. Let us notify the changes to the driver,
1229                  * as some drivers used this to restore its orig_* reg domain.
1230                  */
1231                 if (initiator == NL80211_REGDOM_SET_BY_CORE &&
1232                     wiphy->flags & WIPHY_FLAG_CUSTOM_REGULATORY &&
1233                     wiphy->reg_notifier)
1234                         wiphy->reg_notifier(wiphy, get_last_request());
1235         }
1236 }
1237
1238 static void handle_channel_custom(struct wiphy *wiphy,
1239                                   struct ieee80211_channel *chan,
1240                                   const struct ieee80211_regdomain *regd)
1241 {
1242         u32 bw_flags = 0;
1243         const struct ieee80211_reg_rule *reg_rule = NULL;
1244         const struct ieee80211_power_rule *power_rule = NULL;
1245         const struct ieee80211_freq_range *freq_range = NULL;
1246
1247         reg_rule = freq_reg_info_regd(wiphy, MHZ_TO_KHZ(chan->center_freq),
1248                                       regd);
1249
1250         if (IS_ERR(reg_rule)) {
1251                 REG_DBG_PRINT("Disabling freq %d MHz as custom regd has no rule that fits it\n",
1252                               chan->center_freq);
1253                 chan->flags = IEEE80211_CHAN_DISABLED;
1254                 return;
1255         }
1256
1257         chan_reg_rule_print_dbg(chan, reg_rule);
1258
1259         power_rule = &reg_rule->power_rule;
1260         freq_range = &reg_rule->freq_range;
1261
1262         if (freq_range->max_bandwidth_khz < MHZ_TO_KHZ(40))
1263                 bw_flags = IEEE80211_CHAN_NO_HT40;
1264
1265         chan->flags |= map_regdom_flags(reg_rule->flags) | bw_flags;
1266         chan->max_antenna_gain = (int) MBI_TO_DBI(power_rule->max_antenna_gain);
1267         chan->max_reg_power = chan->max_power =
1268                 (int) MBM_TO_DBM(power_rule->max_eirp);
1269 }
1270
1271 static void handle_band_custom(struct wiphy *wiphy,
1272                                struct ieee80211_supported_band *sband,
1273                                const struct ieee80211_regdomain *regd)
1274 {
1275         unsigned int i;
1276
1277         if (!sband)
1278                 return;
1279
1280         for (i = 0; i < sband->n_channels; i++)
1281                 handle_channel_custom(wiphy, &sband->channels[i], regd);
1282 }
1283
1284 /* Used by drivers prior to wiphy registration */
1285 void wiphy_apply_custom_regulatory(struct wiphy *wiphy,
1286                                    const struct ieee80211_regdomain *regd)
1287 {
1288         enum ieee80211_band band;
1289         unsigned int bands_set = 0;
1290
1291         for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
1292                 if (!wiphy->bands[band])
1293                         continue;
1294                 handle_band_custom(wiphy, wiphy->bands[band], regd);
1295                 bands_set++;
1296         }
1297
1298         /*
1299          * no point in calling this if it won't have any effect
1300          * on your device's supported bands.
1301          */
1302         WARN_ON(!bands_set);
1303 }
1304 EXPORT_SYMBOL(wiphy_apply_custom_regulatory);
1305
1306 /* This has the logic which determines when a new request
1307  * should be ignored. */
1308 static enum reg_request_treatment
1309 get_reg_request_treatment(struct wiphy *wiphy,
1310                           struct regulatory_request *pending_request)
1311 {
1312         struct wiphy *last_wiphy = NULL;
1313         struct regulatory_request *lr = get_last_request();
1314
1315         /* All initial requests are respected */
1316         if (!lr)
1317                 return REG_REQ_OK;
1318
1319         switch (pending_request->initiator) {
1320         case NL80211_REGDOM_SET_BY_CORE:
1321                 return REG_REQ_OK;
1322         case NL80211_REGDOM_SET_BY_COUNTRY_IE:
1323                 if (reg_request_cell_base(lr)) {
1324                         /* Trust a Cell base station over the AP's country IE */
1325                         if (regdom_changes(pending_request->alpha2))
1326                                 return REG_REQ_IGNORE;
1327                         return REG_REQ_ALREADY_SET;
1328                 }
1329
1330                 last_wiphy = wiphy_idx_to_wiphy(lr->wiphy_idx);
1331
1332                 if (unlikely(!is_an_alpha2(pending_request->alpha2)))
1333                         return -EINVAL;
1334                 if (lr->initiator == NL80211_REGDOM_SET_BY_COUNTRY_IE) {
1335                         if (last_wiphy != wiphy) {
1336                                 /*
1337                                  * Two cards with two APs claiming different
1338                                  * Country IE alpha2s. We could
1339                                  * intersect them, but that seems unlikely
1340                                  * to be correct. Reject second one for now.
1341                                  */
1342                                 if (regdom_changes(pending_request->alpha2))
1343                                         return REG_REQ_IGNORE;
1344                                 return REG_REQ_ALREADY_SET;
1345                         }
1346                         /*
1347                          * Two consecutive Country IE hints on the same wiphy.
1348                          * This should be picked up early by the driver/stack
1349                          */
1350                         if (WARN_ON(regdom_changes(pending_request->alpha2)))
1351                                 return REG_REQ_OK;
1352                         return REG_REQ_ALREADY_SET;
1353                 }
1354                 return 0;
1355         case NL80211_REGDOM_SET_BY_DRIVER:
1356                 if (lr->initiator == NL80211_REGDOM_SET_BY_CORE) {
1357                         if (regdom_changes(pending_request->alpha2))
1358                                 return REG_REQ_OK;
1359                         return REG_REQ_ALREADY_SET;
1360                 }
1361
1362                 /*
1363                  * This would happen if you unplug and plug your card
1364                  * back in or if you add a new device for which the previously
1365                  * loaded card also agrees on the regulatory domain.
1366                  */
1367                 if (lr->initiator == NL80211_REGDOM_SET_BY_DRIVER &&
1368                     !regdom_changes(pending_request->alpha2))
1369                         return REG_REQ_ALREADY_SET;
1370
1371                 return REG_REQ_INTERSECT;
1372         case NL80211_REGDOM_SET_BY_USER:
1373                 if (reg_request_cell_base(pending_request))
1374                         return reg_ignore_cell_hint(pending_request);
1375
1376                 if (reg_request_cell_base(lr))
1377                         return REG_REQ_IGNORE;
1378
1379                 if (lr->initiator == NL80211_REGDOM_SET_BY_COUNTRY_IE)
1380                         return REG_REQ_INTERSECT;
1381                 /*
1382                  * If the user knows better the user should set the regdom
1383                  * to their country before the IE is picked up
1384                  */
1385                 if (lr->initiator == NL80211_REGDOM_SET_BY_USER &&
1386                     lr->intersect)
1387                         return REG_REQ_IGNORE;
1388                 /*
1389                  * Process user requests only after previous user/driver/core
1390                  * requests have been processed
1391                  */
1392                 if ((lr->initiator == NL80211_REGDOM_SET_BY_CORE ||
1393                      lr->initiator == NL80211_REGDOM_SET_BY_DRIVER ||
1394                      lr->initiator == NL80211_REGDOM_SET_BY_USER) &&
1395                     regdom_changes(lr->alpha2))
1396                         return REG_REQ_IGNORE;
1397
1398                 if (!regdom_changes(pending_request->alpha2))
1399                         return REG_REQ_ALREADY_SET;
1400
1401                 return REG_REQ_OK;
1402         }
1403
1404         return REG_REQ_IGNORE;
1405 }
1406
1407 static void reg_set_request_processed(void)
1408 {
1409         bool need_more_processing = false;
1410         struct regulatory_request *lr = get_last_request();
1411
1412         lr->processed = true;
1413
1414         spin_lock(&reg_requests_lock);
1415         if (!list_empty(&reg_requests_list))
1416                 need_more_processing = true;
1417         spin_unlock(&reg_requests_lock);
1418
1419         if (lr->initiator == NL80211_REGDOM_SET_BY_USER)
1420                 cancel_delayed_work(&reg_timeout);
1421
1422         if (need_more_processing)
1423                 schedule_work(&reg_work);
1424 }
1425
1426 /**
1427  * __regulatory_hint - hint to the wireless core a regulatory domain
1428  * @wiphy: if the hint comes from country information from an AP, this
1429  *      is required to be set to the wiphy that received the information
1430  * @pending_request: the regulatory request currently being processed
1431  *
1432  * The Wireless subsystem can use this function to hint to the wireless core
1433  * what it believes should be the current regulatory domain.
1434  *
1435  * Returns one of the different reg request treatment values.
1436  *
1437  * Caller must hold &reg_mutex
1438  */
1439 static enum reg_request_treatment
1440 __regulatory_hint(struct wiphy *wiphy,
1441                   struct regulatory_request *pending_request)
1442 {
1443         const struct ieee80211_regdomain *regd;
1444         bool intersect = false;
1445         enum reg_request_treatment treatment;
1446         struct regulatory_request *lr;
1447
1448         treatment = get_reg_request_treatment(wiphy, pending_request);
1449
1450         switch (treatment) {
1451         case REG_REQ_INTERSECT:
1452                 if (pending_request->initiator ==
1453                     NL80211_REGDOM_SET_BY_DRIVER) {
1454                         regd = reg_copy_regd(get_cfg80211_regdom());
1455                         if (IS_ERR(regd)) {
1456                                 kfree(pending_request);
1457                                 return PTR_ERR(regd);
1458                         }
1459                         rcu_assign_pointer(wiphy->regd, regd);
1460                 }
1461                 intersect = true;
1462                 break;
1463         case REG_REQ_OK:
1464                 break;
1465         default:
1466                 /*
1467                  * If the regulatory domain being requested by the
1468                  * driver has already been set just copy it to the
1469                  * wiphy
1470                  */
1471                 if (treatment == REG_REQ_ALREADY_SET &&
1472                     pending_request->initiator == NL80211_REGDOM_SET_BY_DRIVER) {
1473                         regd = reg_copy_regd(get_cfg80211_regdom());
1474                         if (IS_ERR(regd)) {
1475                                 kfree(pending_request);
1476                                 return REG_REQ_IGNORE;
1477                         }
1478                         treatment = REG_REQ_ALREADY_SET;
1479                         rcu_assign_pointer(wiphy->regd, regd);
1480                         goto new_request;
1481                 }
1482                 kfree(pending_request);
1483                 return treatment;
1484         }
1485
1486 new_request:
1487         lr = get_last_request();
1488         if (lr != &core_request_world && lr)
1489                 kfree_rcu(lr, rcu_head);
1490
1491         pending_request->intersect = intersect;
1492         pending_request->processed = false;
1493         rcu_assign_pointer(last_request, pending_request);
1494         lr = pending_request;
1495
1496         pending_request = NULL;
1497
1498         if (lr->initiator == NL80211_REGDOM_SET_BY_USER) {
1499                 user_alpha2[0] = lr->alpha2[0];
1500                 user_alpha2[1] = lr->alpha2[1];
1501         }
1502
1503         /* When r == REG_REQ_INTERSECT we do need to call CRDA */
1504         if (treatment != REG_REQ_OK && treatment != REG_REQ_INTERSECT) {
1505                 /*
1506                  * Since CRDA will not be called in this case as we already
1507                  * have applied the requested regulatory domain before we just
1508                  * inform userspace we have processed the request
1509                  */
1510                 if (treatment == REG_REQ_ALREADY_SET) {
1511                         nl80211_send_reg_change_event(lr);
1512                         reg_set_request_processed();
1513                 }
1514                 return treatment;
1515         }
1516
1517         if (call_crda(lr->alpha2))
1518                 return REG_REQ_IGNORE;
1519         return REG_REQ_OK;
1520 }
1521
1522 /* This processes *all* regulatory hints */
1523 static void reg_process_hint(struct regulatory_request *reg_request,
1524                              enum nl80211_reg_initiator reg_initiator)
1525 {
1526         struct wiphy *wiphy = NULL;
1527
1528         if (WARN_ON(!reg_request->alpha2))
1529                 return;
1530
1531         if (reg_request->wiphy_idx != WIPHY_IDX_INVALID)
1532                 wiphy = wiphy_idx_to_wiphy(reg_request->wiphy_idx);
1533
1534         if (reg_initiator == NL80211_REGDOM_SET_BY_DRIVER && !wiphy) {
1535                 kfree(reg_request);
1536                 return;
1537         }
1538
1539         switch (__regulatory_hint(wiphy, reg_request)) {
1540         case REG_REQ_ALREADY_SET:
1541                 /* This is required so that the orig_* parameters are saved */
1542                 if (wiphy && wiphy->flags & WIPHY_FLAG_STRICT_REGULATORY)
1543                         wiphy_update_regulatory(wiphy, reg_initiator);
1544                 break;
1545         default:
1546                 if (reg_initiator == NL80211_REGDOM_SET_BY_USER)
1547                         schedule_delayed_work(&reg_timeout,
1548                                               msecs_to_jiffies(3142));
1549                 break;
1550         }
1551 }
1552
1553 /*
1554  * Processes regulatory hints, this is all the NL80211_REGDOM_SET_BY_*
1555  * Regulatory hints come on a first come first serve basis and we
1556  * must process each one atomically.
1557  */
1558 static void reg_process_pending_hints(void)
1559 {
1560         struct regulatory_request *reg_request, *lr;
1561
1562         mutex_lock(&cfg80211_mutex);
1563         mutex_lock(&reg_mutex);
1564         lr = get_last_request();
1565
1566         /* When last_request->processed becomes true this will be rescheduled */
1567         if (lr && !lr->processed) {
1568                 REG_DBG_PRINT("Pending regulatory request, waiting for it to be processed...\n");
1569                 goto out;
1570         }
1571
1572         spin_lock(&reg_requests_lock);
1573
1574         if (list_empty(&reg_requests_list)) {
1575                 spin_unlock(&reg_requests_lock);
1576                 goto out;
1577         }
1578
1579         reg_request = list_first_entry(&reg_requests_list,
1580                                        struct regulatory_request,
1581                                        list);
1582         list_del_init(&reg_request->list);
1583
1584         spin_unlock(&reg_requests_lock);
1585
1586         reg_process_hint(reg_request, reg_request->initiator);
1587
1588 out:
1589         mutex_unlock(&reg_mutex);
1590         mutex_unlock(&cfg80211_mutex);
1591 }
1592
1593 /* Processes beacon hints -- this has nothing to do with country IEs */
1594 static void reg_process_pending_beacon_hints(void)
1595 {
1596         struct cfg80211_registered_device *rdev;
1597         struct reg_beacon *pending_beacon, *tmp;
1598
1599         mutex_lock(&cfg80211_mutex);
1600         mutex_lock(&reg_mutex);
1601
1602         /* This goes through the _pending_ beacon list */
1603         spin_lock_bh(&reg_pending_beacons_lock);
1604
1605         list_for_each_entry_safe(pending_beacon, tmp,
1606                                  &reg_pending_beacons, list) {
1607                 list_del_init(&pending_beacon->list);
1608
1609                 /* Applies the beacon hint to current wiphys */
1610                 list_for_each_entry(rdev, &cfg80211_rdev_list, list)
1611                         wiphy_update_new_beacon(&rdev->wiphy, pending_beacon);
1612
1613                 /* Remembers the beacon hint for new wiphys or reg changes */
1614                 list_add_tail(&pending_beacon->list, &reg_beacon_list);
1615         }
1616
1617         spin_unlock_bh(&reg_pending_beacons_lock);
1618         mutex_unlock(&reg_mutex);
1619         mutex_unlock(&cfg80211_mutex);
1620 }
1621
1622 static void reg_todo(struct work_struct *work)
1623 {
1624         reg_process_pending_hints();
1625         reg_process_pending_beacon_hints();
1626 }
1627
1628 static void queue_regulatory_request(struct regulatory_request *request)
1629 {
1630         request->alpha2[0] = toupper(request->alpha2[0]);
1631         request->alpha2[1] = toupper(request->alpha2[1]);
1632
1633         spin_lock(&reg_requests_lock);
1634         list_add_tail(&request->list, &reg_requests_list);
1635         spin_unlock(&reg_requests_lock);
1636
1637         schedule_work(&reg_work);
1638 }
1639
1640 /*
1641  * Core regulatory hint -- happens during cfg80211_init()
1642  * and when we restore regulatory settings.
1643  */
1644 static int regulatory_hint_core(const char *alpha2)
1645 {
1646         struct regulatory_request *request;
1647
1648         request = kzalloc(sizeof(struct regulatory_request), GFP_KERNEL);
1649         if (!request)
1650                 return -ENOMEM;
1651
1652         request->alpha2[0] = alpha2[0];
1653         request->alpha2[1] = alpha2[1];
1654         request->initiator = NL80211_REGDOM_SET_BY_CORE;
1655
1656         queue_regulatory_request(request);
1657
1658         return 0;
1659 }
1660
1661 /* User hints */
1662 int regulatory_hint_user(const char *alpha2,
1663                          enum nl80211_user_reg_hint_type user_reg_hint_type)
1664 {
1665         struct regulatory_request *request;
1666
1667         if (WARN_ON(!alpha2))
1668                 return -EINVAL;
1669
1670         request = kzalloc(sizeof(struct regulatory_request), GFP_KERNEL);
1671         if (!request)
1672                 return -ENOMEM;
1673
1674         request->wiphy_idx = WIPHY_IDX_INVALID;
1675         request->alpha2[0] = alpha2[0];
1676         request->alpha2[1] = alpha2[1];
1677         request->initiator = NL80211_REGDOM_SET_BY_USER;
1678         request->user_reg_hint_type = user_reg_hint_type;
1679
1680         queue_regulatory_request(request);
1681
1682         return 0;
1683 }
1684
1685 /* Driver hints */
1686 int regulatory_hint(struct wiphy *wiphy, const char *alpha2)
1687 {
1688         struct regulatory_request *request;
1689
1690         if (WARN_ON(!alpha2 || !wiphy))
1691                 return -EINVAL;
1692
1693         request = kzalloc(sizeof(struct regulatory_request), GFP_KERNEL);
1694         if (!request)
1695                 return -ENOMEM;
1696
1697         request->wiphy_idx = get_wiphy_idx(wiphy);
1698
1699         request->alpha2[0] = alpha2[0];
1700         request->alpha2[1] = alpha2[1];
1701         request->initiator = NL80211_REGDOM_SET_BY_DRIVER;
1702
1703         queue_regulatory_request(request);
1704
1705         return 0;
1706 }
1707 EXPORT_SYMBOL(regulatory_hint);
1708
1709 /*
1710  * We hold wdev_lock() here so we cannot hold cfg80211_mutex() and
1711  * therefore cannot iterate over the rdev list here.
1712  */
1713 void regulatory_hint_11d(struct wiphy *wiphy, enum ieee80211_band band,
1714                          const u8 *country_ie, u8 country_ie_len)
1715 {
1716         char alpha2[2];
1717         enum environment_cap env = ENVIRON_ANY;
1718         struct regulatory_request *request, *lr;
1719
1720         mutex_lock(&reg_mutex);
1721         lr = get_last_request();
1722
1723         if (unlikely(!lr))
1724                 goto out;
1725
1726         /* IE len must be evenly divisible by 2 */
1727         if (country_ie_len & 0x01)
1728                 goto out;
1729
1730         if (country_ie_len < IEEE80211_COUNTRY_IE_MIN_LEN)
1731                 goto out;
1732
1733         alpha2[0] = country_ie[0];
1734         alpha2[1] = country_ie[1];
1735
1736         if (country_ie[2] == 'I')
1737                 env = ENVIRON_INDOOR;
1738         else if (country_ie[2] == 'O')
1739                 env = ENVIRON_OUTDOOR;
1740
1741         /*
1742          * We will run this only upon a successful connection on cfg80211.
1743          * We leave conflict resolution to the workqueue, where can hold
1744          * cfg80211_mutex.
1745          */
1746         if (lr->initiator == NL80211_REGDOM_SET_BY_COUNTRY_IE &&
1747             lr->wiphy_idx != WIPHY_IDX_INVALID)
1748                 goto out;
1749
1750         request = kzalloc(sizeof(struct regulatory_request), GFP_KERNEL);
1751         if (!request)
1752                 goto out;
1753
1754         request->wiphy_idx = get_wiphy_idx(wiphy);
1755         request->alpha2[0] = alpha2[0];
1756         request->alpha2[1] = alpha2[1];
1757         request->initiator = NL80211_REGDOM_SET_BY_COUNTRY_IE;
1758         request->country_ie_env = env;
1759
1760         queue_regulatory_request(request);
1761 out:
1762         mutex_unlock(&reg_mutex);
1763 }
1764
1765 static void restore_alpha2(char *alpha2, bool reset_user)
1766 {
1767         /* indicates there is no alpha2 to consider for restoration */
1768         alpha2[0] = '9';
1769         alpha2[1] = '7';
1770
1771         /* The user setting has precedence over the module parameter */
1772         if (is_user_regdom_saved()) {
1773                 /* Unless we're asked to ignore it and reset it */
1774                 if (reset_user) {
1775                         REG_DBG_PRINT("Restoring regulatory settings including user preference\n");
1776                         user_alpha2[0] = '9';
1777                         user_alpha2[1] = '7';
1778
1779                         /*
1780                          * If we're ignoring user settings, we still need to
1781                          * check the module parameter to ensure we put things
1782                          * back as they were for a full restore.
1783                          */
1784                         if (!is_world_regdom(ieee80211_regdom)) {
1785                                 REG_DBG_PRINT("Keeping preference on module parameter ieee80211_regdom: %c%c\n",
1786                                               ieee80211_regdom[0], ieee80211_regdom[1]);
1787                                 alpha2[0] = ieee80211_regdom[0];
1788                                 alpha2[1] = ieee80211_regdom[1];
1789                         }
1790                 } else {
1791                         REG_DBG_PRINT("Restoring regulatory settings while preserving user preference for: %c%c\n",
1792                                       user_alpha2[0], user_alpha2[1]);
1793                         alpha2[0] = user_alpha2[0];
1794                         alpha2[1] = user_alpha2[1];
1795                 }
1796         } else if (!is_world_regdom(ieee80211_regdom)) {
1797                 REG_DBG_PRINT("Keeping preference on module parameter ieee80211_regdom: %c%c\n",
1798                               ieee80211_regdom[0], ieee80211_regdom[1]);
1799                 alpha2[0] = ieee80211_regdom[0];
1800                 alpha2[1] = ieee80211_regdom[1];
1801         } else
1802                 REG_DBG_PRINT("Restoring regulatory settings\n");
1803 }
1804
1805 static void restore_custom_reg_settings(struct wiphy *wiphy)
1806 {
1807         struct ieee80211_supported_band *sband;
1808         enum ieee80211_band band;
1809         struct ieee80211_channel *chan;
1810         int i;
1811
1812         for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
1813                 sband = wiphy->bands[band];
1814                 if (!sband)
1815                         continue;
1816                 for (i = 0; i < sband->n_channels; i++) {
1817                         chan = &sband->channels[i];
1818                         chan->flags = chan->orig_flags;
1819                         chan->max_antenna_gain = chan->orig_mag;
1820                         chan->max_power = chan->orig_mpwr;
1821                         chan->beacon_found = false;
1822                 }
1823         }
1824 }
1825
1826 /*
1827  * Restoring regulatory settings involves ingoring any
1828  * possibly stale country IE information and user regulatory
1829  * settings if so desired, this includes any beacon hints
1830  * learned as we could have traveled outside to another country
1831  * after disconnection. To restore regulatory settings we do
1832  * exactly what we did at bootup:
1833  *
1834  *   - send a core regulatory hint
1835  *   - send a user regulatory hint if applicable
1836  *
1837  * Device drivers that send a regulatory hint for a specific country
1838  * keep their own regulatory domain on wiphy->regd so that does does
1839  * not need to be remembered.
1840  */
1841 static void restore_regulatory_settings(bool reset_user)
1842 {
1843         char alpha2[2];
1844         char world_alpha2[2];
1845         struct reg_beacon *reg_beacon, *btmp;
1846         struct regulatory_request *reg_request, *tmp;
1847         LIST_HEAD(tmp_reg_req_list);
1848         struct cfg80211_registered_device *rdev;
1849
1850         mutex_lock(&cfg80211_mutex);
1851         mutex_lock(&reg_mutex);
1852
1853         reset_regdomains(true, &world_regdom);
1854         restore_alpha2(alpha2, reset_user);
1855
1856         /*
1857          * If there's any pending requests we simply
1858          * stash them to a temporary pending queue and
1859          * add then after we've restored regulatory
1860          * settings.
1861          */
1862         spin_lock(&reg_requests_lock);
1863         list_for_each_entry_safe(reg_request, tmp, &reg_requests_list, list) {
1864                 if (reg_request->initiator != NL80211_REGDOM_SET_BY_USER)
1865                         continue;
1866                 list_move_tail(&reg_request->list, &tmp_reg_req_list);
1867         }
1868         spin_unlock(&reg_requests_lock);
1869
1870         /* Clear beacon hints */
1871         spin_lock_bh(&reg_pending_beacons_lock);
1872         list_for_each_entry_safe(reg_beacon, btmp, &reg_pending_beacons, list) {
1873                 list_del(&reg_beacon->list);
1874                 kfree(reg_beacon);
1875         }
1876         spin_unlock_bh(&reg_pending_beacons_lock);
1877
1878         list_for_each_entry_safe(reg_beacon, btmp, &reg_beacon_list, list) {
1879                 list_del(&reg_beacon->list);
1880                 kfree(reg_beacon);
1881         }
1882
1883         /* First restore to the basic regulatory settings */
1884         world_alpha2[0] = cfg80211_world_regdom->alpha2[0];
1885         world_alpha2[1] = cfg80211_world_regdom->alpha2[1];
1886
1887         list_for_each_entry(rdev, &cfg80211_rdev_list, list) {
1888                 if (rdev->wiphy.flags & WIPHY_FLAG_CUSTOM_REGULATORY)
1889                         restore_custom_reg_settings(&rdev->wiphy);
1890         }
1891
1892         regulatory_hint_core(world_alpha2);
1893
1894         /*
1895          * This restores the ieee80211_regdom module parameter
1896          * preference or the last user requested regulatory
1897          * settings, user regulatory settings takes precedence.
1898          */
1899         if (is_an_alpha2(alpha2))
1900                 regulatory_hint_user(user_alpha2, NL80211_USER_REG_HINT_USER);
1901
1902         spin_lock(&reg_requests_lock);
1903         list_splice_tail_init(&tmp_reg_req_list, &reg_requests_list);
1904         spin_unlock(&reg_requests_lock);
1905
1906         mutex_unlock(&reg_mutex);
1907         mutex_unlock(&cfg80211_mutex);
1908
1909         REG_DBG_PRINT("Kicking the queue\n");
1910
1911         schedule_work(&reg_work);
1912 }
1913
1914 void regulatory_hint_disconnect(void)
1915 {
1916         REG_DBG_PRINT("All devices are disconnected, going to restore regulatory settings\n");
1917         restore_regulatory_settings(false);
1918 }
1919
1920 static bool freq_is_chan_12_13_14(u16 freq)
1921 {
1922         if (freq == ieee80211_channel_to_frequency(12, IEEE80211_BAND_2GHZ) ||
1923             freq == ieee80211_channel_to_frequency(13, IEEE80211_BAND_2GHZ) ||
1924             freq == ieee80211_channel_to_frequency(14, IEEE80211_BAND_2GHZ))
1925                 return true;
1926         return false;
1927 }
1928
1929 static bool pending_reg_beacon(struct ieee80211_channel *beacon_chan)
1930 {
1931         struct reg_beacon *pending_beacon;
1932
1933         list_for_each_entry(pending_beacon, &reg_pending_beacons, list)
1934                 if (beacon_chan->center_freq ==
1935                     pending_beacon->chan.center_freq)
1936                         return true;
1937         return false;
1938 }
1939
1940 int regulatory_hint_found_beacon(struct wiphy *wiphy,
1941                                  struct ieee80211_channel *beacon_chan,
1942                                  gfp_t gfp)
1943 {
1944         struct reg_beacon *reg_beacon;
1945         bool processing;
1946
1947         if (beacon_chan->beacon_found ||
1948             beacon_chan->flags & IEEE80211_CHAN_RADAR ||
1949             (beacon_chan->band == IEEE80211_BAND_2GHZ &&
1950              !freq_is_chan_12_13_14(beacon_chan->center_freq)))
1951                 return 0;
1952
1953         spin_lock_bh(&reg_pending_beacons_lock);
1954         processing = pending_reg_beacon(beacon_chan);
1955         spin_unlock_bh(&reg_pending_beacons_lock);
1956
1957         if (processing)
1958                 return 0;
1959
1960         reg_beacon = kzalloc(sizeof(struct reg_beacon), gfp);
1961         if (!reg_beacon)
1962                 return -ENOMEM;
1963
1964         REG_DBG_PRINT("Found new beacon on frequency: %d MHz (Ch %d) on %s\n",
1965                       beacon_chan->center_freq,
1966                       ieee80211_frequency_to_channel(beacon_chan->center_freq),
1967                       wiphy_name(wiphy));
1968
1969         memcpy(&reg_beacon->chan, beacon_chan,
1970                sizeof(struct ieee80211_channel));
1971
1972         /*
1973          * Since we can be called from BH or and non-BH context
1974          * we must use spin_lock_bh()
1975          */
1976         spin_lock_bh(&reg_pending_beacons_lock);
1977         list_add_tail(&reg_beacon->list, &reg_pending_beacons);
1978         spin_unlock_bh(&reg_pending_beacons_lock);
1979
1980         schedule_work(&reg_work);
1981
1982         return 0;
1983 }
1984
1985 static void print_rd_rules(const struct ieee80211_regdomain *rd)
1986 {
1987         unsigned int i;
1988         const struct ieee80211_reg_rule *reg_rule = NULL;
1989         const struct ieee80211_freq_range *freq_range = NULL;
1990         const struct ieee80211_power_rule *power_rule = NULL;
1991
1992         pr_info("  (start_freq - end_freq @ bandwidth), (max_antenna_gain, max_eirp)\n");
1993
1994         for (i = 0; i < rd->n_reg_rules; i++) {
1995                 reg_rule = &rd->reg_rules[i];
1996                 freq_range = &reg_rule->freq_range;
1997                 power_rule = &reg_rule->power_rule;
1998
1999                 /*
2000                  * There may not be documentation for max antenna gain
2001                  * in certain regions
2002                  */
2003                 if (power_rule->max_antenna_gain)
2004                         pr_info("  (%d KHz - %d KHz @ %d KHz), (%d mBi, %d mBm)\n",
2005                                 freq_range->start_freq_khz,
2006                                 freq_range->end_freq_khz,
2007                                 freq_range->max_bandwidth_khz,
2008                                 power_rule->max_antenna_gain,
2009                                 power_rule->max_eirp);
2010                 else
2011                         pr_info("  (%d KHz - %d KHz @ %d KHz), (N/A, %d mBm)\n",
2012                                 freq_range->start_freq_khz,
2013                                 freq_range->end_freq_khz,
2014                                 freq_range->max_bandwidth_khz,
2015                                 power_rule->max_eirp);
2016         }
2017 }
2018
2019 bool reg_supported_dfs_region(u8 dfs_region)
2020 {
2021         switch (dfs_region) {
2022         case NL80211_DFS_UNSET:
2023         case NL80211_DFS_FCC:
2024         case NL80211_DFS_ETSI:
2025         case NL80211_DFS_JP:
2026                 return true;
2027         default:
2028                 REG_DBG_PRINT("Ignoring uknown DFS master region: %d\n",
2029                               dfs_region);
2030                 return false;
2031         }
2032 }
2033
2034 static void print_dfs_region(u8 dfs_region)
2035 {
2036         if (!dfs_region)
2037                 return;
2038
2039         switch (dfs_region) {
2040         case NL80211_DFS_FCC:
2041                 pr_info(" DFS Master region FCC");
2042                 break;
2043         case NL80211_DFS_ETSI:
2044                 pr_info(" DFS Master region ETSI");
2045                 break;
2046         case NL80211_DFS_JP:
2047                 pr_info(" DFS Master region JP");
2048                 break;
2049         default:
2050                 pr_info(" DFS Master region Unknown");
2051                 break;
2052         }
2053 }
2054
2055 static void print_regdomain(const struct ieee80211_regdomain *rd)
2056 {
2057         struct regulatory_request *lr = get_last_request();
2058
2059         if (is_intersected_alpha2(rd->alpha2)) {
2060                 if (lr->initiator == NL80211_REGDOM_SET_BY_COUNTRY_IE) {
2061                         struct cfg80211_registered_device *rdev;
2062                         rdev = cfg80211_rdev_by_wiphy_idx(lr->wiphy_idx);
2063                         if (rdev) {
2064                                 pr_info("Current regulatory domain updated by AP to: %c%c\n",
2065                                         rdev->country_ie_alpha2[0],
2066                                         rdev->country_ie_alpha2[1]);
2067                         } else
2068                                 pr_info("Current regulatory domain intersected:\n");
2069                 } else
2070                         pr_info("Current regulatory domain intersected:\n");
2071         } else if (is_world_regdom(rd->alpha2)) {
2072                 pr_info("World regulatory domain updated:\n");
2073         } else {
2074                 if (is_unknown_alpha2(rd->alpha2))
2075                         pr_info("Regulatory domain changed to driver built-in settings (unknown country)\n");
2076                 else {
2077                         if (reg_request_cell_base(lr))
2078                                 pr_info("Regulatory domain changed to country: %c%c by Cell Station\n",
2079                                         rd->alpha2[0], rd->alpha2[1]);
2080                         else
2081                                 pr_info("Regulatory domain changed to country: %c%c\n",
2082                                         rd->alpha2[0], rd->alpha2[1]);
2083                 }
2084         }
2085
2086         print_dfs_region(rd->dfs_region);
2087         print_rd_rules(rd);
2088 }
2089
2090 static void print_regdomain_info(const struct ieee80211_regdomain *rd)
2091 {
2092         pr_info("Regulatory domain: %c%c\n", rd->alpha2[0], rd->alpha2[1]);
2093         print_rd_rules(rd);
2094 }
2095
2096 /* Takes ownership of rd only if it doesn't fail */
2097 static int __set_regdom(const struct ieee80211_regdomain *rd)
2098 {
2099         const struct ieee80211_regdomain *regd;
2100         const struct ieee80211_regdomain *intersected_rd = NULL;
2101         struct wiphy *request_wiphy;
2102         struct regulatory_request *lr = get_last_request();
2103
2104         /* Some basic sanity checks first */
2105
2106         if (!reg_is_valid_request(rd->alpha2))
2107                 return -EINVAL;
2108
2109         if (is_world_regdom(rd->alpha2)) {
2110                 update_world_regdomain(rd);
2111                 return 0;
2112         }
2113
2114         if (!is_alpha2_set(rd->alpha2) && !is_an_alpha2(rd->alpha2) &&
2115             !is_unknown_alpha2(rd->alpha2))
2116                 return -EINVAL;
2117
2118         /*
2119          * Lets only bother proceeding on the same alpha2 if the current
2120          * rd is non static (it means CRDA was present and was used last)
2121          * and the pending request came in from a country IE
2122          */
2123         if (lr->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE) {
2124                 /*
2125                  * If someone else asked us to change the rd lets only bother
2126                  * checking if the alpha2 changes if CRDA was already called
2127                  */
2128                 if (!regdom_changes(rd->alpha2))
2129                         return -EALREADY;
2130         }
2131
2132         /*
2133          * Now lets set the regulatory domain, update all driver channels
2134          * and finally inform them of what we have done, in case they want
2135          * to review or adjust their own settings based on their own
2136          * internal EEPROM data
2137          */
2138
2139         if (!is_valid_rd(rd)) {
2140                 pr_err("Invalid regulatory domain detected:\n");
2141                 print_regdomain_info(rd);
2142                 return -EINVAL;
2143         }
2144
2145         request_wiphy = wiphy_idx_to_wiphy(lr->wiphy_idx);
2146         if (!request_wiphy &&
2147             (lr->initiator == NL80211_REGDOM_SET_BY_DRIVER ||
2148              lr->initiator == NL80211_REGDOM_SET_BY_COUNTRY_IE)) {
2149                 schedule_delayed_work(&reg_timeout, 0);
2150                 return -ENODEV;
2151         }
2152
2153         if (!lr->intersect) {
2154                 if (lr->initiator != NL80211_REGDOM_SET_BY_DRIVER) {
2155                         reset_regdomains(false, rd);
2156                         return 0;
2157                 }
2158
2159                 /*
2160                  * For a driver hint, lets copy the regulatory domain the
2161                  * driver wanted to the wiphy to deal with conflicts
2162                  */
2163
2164                 /*
2165                  * Userspace could have sent two replies with only
2166                  * one kernel request.
2167                  */
2168                 if (request_wiphy->regd)
2169                         return -EALREADY;
2170
2171                 regd = reg_copy_regd(rd);
2172                 if (IS_ERR(regd))
2173                         return PTR_ERR(regd);
2174
2175                 rcu_assign_pointer(request_wiphy->regd, regd);
2176                 reset_regdomains(false, rd);
2177                 return 0;
2178         }
2179
2180         /* Intersection requires a bit more work */
2181
2182         if (lr->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE) {
2183                 intersected_rd = regdom_intersect(rd, get_cfg80211_regdom());
2184                 if (!intersected_rd)
2185                         return -EINVAL;
2186
2187                 /*
2188                  * We can trash what CRDA provided now.
2189                  * However if a driver requested this specific regulatory
2190                  * domain we keep it for its private use
2191                  */
2192                 if (lr->initiator == NL80211_REGDOM_SET_BY_DRIVER)
2193                         rcu_assign_pointer(request_wiphy->regd, rd);
2194                 else
2195                         kfree(rd);
2196
2197                 rd = NULL;
2198
2199                 reset_regdomains(false, intersected_rd);
2200
2201                 return 0;
2202         }
2203
2204         return -EINVAL;
2205 }
2206
2207
2208 /*
2209  * Use this call to set the current regulatory domain. Conflicts with
2210  * multiple drivers can be ironed out later. Caller must've already
2211  * kmalloc'd the rd structure.
2212  */
2213 int set_regdom(const struct ieee80211_regdomain *rd)
2214 {
2215         struct regulatory_request *lr;
2216         int r;
2217
2218         mutex_lock(&reg_mutex);
2219         lr = get_last_request();
2220
2221         /* Note that this doesn't update the wiphys, this is done below */
2222         r = __set_regdom(rd);
2223         if (r) {
2224                 if (r == -EALREADY)
2225                         reg_set_request_processed();
2226
2227                 kfree(rd);
2228                 goto out;
2229         }
2230
2231         /* This would make this whole thing pointless */
2232         if (WARN_ON(!lr->intersect && rd != get_cfg80211_regdom())) {
2233                 r = -EINVAL;
2234                 goto out;
2235         }
2236
2237         /* update all wiphys now with the new established regulatory domain */
2238         update_all_wiphy_regulatory(lr->initiator);
2239
2240         print_regdomain(get_cfg80211_regdom());
2241
2242         nl80211_send_reg_change_event(lr);
2243
2244         reg_set_request_processed();
2245
2246  out:
2247         mutex_unlock(&reg_mutex);
2248
2249         return r;
2250 }
2251
2252 int reg_device_uevent(struct device *dev, struct kobj_uevent_env *env)
2253 {
2254         struct regulatory_request *lr;
2255         u8 alpha2[2];
2256         bool add = false;
2257
2258         rcu_read_lock();
2259         lr = get_last_request();
2260         if (lr && !lr->processed) {
2261                 memcpy(alpha2, lr->alpha2, 2);
2262                 add = true;
2263         }
2264         rcu_read_unlock();
2265
2266         if (add)
2267                 return add_uevent_var(env, "COUNTRY=%c%c",
2268                                       alpha2[0], alpha2[1]);
2269         return 0;
2270 }
2271
2272 void wiphy_regulatory_register(struct wiphy *wiphy)
2273 {
2274         mutex_lock(&reg_mutex);
2275
2276         if (!reg_dev_ignore_cell_hint(wiphy))
2277                 reg_num_devs_support_basehint++;
2278
2279         wiphy_update_regulatory(wiphy, NL80211_REGDOM_SET_BY_CORE);
2280
2281         mutex_unlock(&reg_mutex);
2282 }
2283
2284 /* Caller must hold cfg80211_mutex */
2285 void wiphy_regulatory_deregister(struct wiphy *wiphy)
2286 {
2287         struct wiphy *request_wiphy = NULL;
2288         struct regulatory_request *lr;
2289
2290         mutex_lock(&reg_mutex);
2291         lr = get_last_request();
2292
2293         if (!reg_dev_ignore_cell_hint(wiphy))
2294                 reg_num_devs_support_basehint--;
2295
2296         rcu_free_regdom(get_wiphy_regdom(wiphy));
2297         rcu_assign_pointer(wiphy->regd, NULL);
2298
2299         if (lr)
2300                 request_wiphy = wiphy_idx_to_wiphy(lr->wiphy_idx);
2301
2302         if (!request_wiphy || request_wiphy != wiphy)
2303                 goto out;
2304
2305         lr->wiphy_idx = WIPHY_IDX_INVALID;
2306         lr->country_ie_env = ENVIRON_ANY;
2307 out:
2308         mutex_unlock(&reg_mutex);
2309 }
2310
2311 static void reg_timeout_work(struct work_struct *work)
2312 {
2313         REG_DBG_PRINT("Timeout while waiting for CRDA to reply, restoring regulatory settings\n");
2314         restore_regulatory_settings(true);
2315 }
2316
2317 int __init regulatory_init(void)
2318 {
2319         int err = 0;
2320
2321         reg_pdev = platform_device_register_simple("regulatory", 0, NULL, 0);
2322         if (IS_ERR(reg_pdev))
2323                 return PTR_ERR(reg_pdev);
2324
2325         reg_pdev->dev.type = &reg_device_type;
2326
2327         spin_lock_init(&reg_requests_lock);
2328         spin_lock_init(&reg_pending_beacons_lock);
2329
2330         reg_regdb_size_check();
2331
2332         rcu_assign_pointer(cfg80211_regdomain, cfg80211_world_regdom);
2333
2334         user_alpha2[0] = '9';
2335         user_alpha2[1] = '7';
2336
2337         /* We always try to get an update for the static regdomain */
2338         err = regulatory_hint_core(cfg80211_world_regdom->alpha2);
2339         if (err) {
2340                 if (err == -ENOMEM)
2341                         return err;
2342                 /*
2343                  * N.B. kobject_uevent_env() can fail mainly for when we're out
2344                  * memory which is handled and propagated appropriately above
2345                  * but it can also fail during a netlink_broadcast() or during
2346                  * early boot for call_usermodehelper(). For now treat these
2347                  * errors as non-fatal.
2348                  */
2349                 pr_err("kobject_uevent_env() was unable to call CRDA during init\n");
2350         }
2351
2352         /*
2353          * Finally, if the user set the module parameter treat it
2354          * as a user hint.
2355          */
2356         if (!is_world_regdom(ieee80211_regdom))
2357                 regulatory_hint_user(ieee80211_regdom,
2358                                      NL80211_USER_REG_HINT_USER);
2359
2360         return 0;
2361 }
2362
2363 void regulatory_exit(void)
2364 {
2365         struct regulatory_request *reg_request, *tmp;
2366         struct reg_beacon *reg_beacon, *btmp;
2367
2368         cancel_work_sync(&reg_work);
2369         cancel_delayed_work_sync(&reg_timeout);
2370
2371         /* Lock to suppress warnings */
2372         mutex_lock(&reg_mutex);
2373         reset_regdomains(true, NULL);
2374         mutex_unlock(&reg_mutex);
2375
2376         dev_set_uevent_suppress(&reg_pdev->dev, true);
2377
2378         platform_device_unregister(reg_pdev);
2379
2380         list_for_each_entry_safe(reg_beacon, btmp, &reg_pending_beacons, list) {
2381                 list_del(&reg_beacon->list);
2382                 kfree(reg_beacon);
2383         }
2384
2385         list_for_each_entry_safe(reg_beacon, btmp, &reg_beacon_list, list) {
2386                 list_del(&reg_beacon->list);
2387                 kfree(reg_beacon);
2388         }
2389
2390         list_for_each_entry_safe(reg_request, tmp, &reg_requests_list, list) {
2391                 list_del(&reg_request->list);
2392                 kfree(reg_request);
2393         }
2394 }