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       Luis R. Rodriguez <lrodriguz@atheros.com>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  */
  11
  12 /**
  13  * DOC: Wireless regulatory infrastructure
  14  *
  15  * The usual implementation is for a driver to read a device EEPROM to
  16  * determine which regulatory domain it should be operating under, then
  17  * looking up the allowable channels in a driver-local table and finally
  18  * registering those channels in the wiphy structure.
  19  *
  20  * Another set of compliance enforcement is for drivers to use their
  21  * own compliance limits which can be stored on the EEPROM. The host
  22  * driver or firmware may ensure these are used.
  23  *
  24  * In addition to all this we provide an extra layer of regulatory
  25  * conformance. For drivers which do not have any regulatory
  26  * information CRDA provides the complete regulatory solution.
  27  * For others it provides a community effort on further restrictions
  28  * to enhance compliance.
  29  *
  30  * Note: When number of rules --> infinity we will not be able to
  31  * index on alpha2 any more, instead we'll probably have to
  32  * rely on some SHA1 checksum of the regdomain for example.
  33  *
  34  */
  35
  36 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  37
  38 #include <linux/kernel.h>
  39 #include <linux/export.h>
  40 #include <linux/slab.h>
  41 #include <linux/list.h>
  42 #include <linux/random.h>
  43 #include <linux/ctype.h>
  44 #include <linux/nl80211.h>
  45 #include <linux/platform_device.h>
  46 #include <linux/moduleparam.h>
  47 #include <net/cfg80211.h>
  48 #include "core.h"
  49 #include "reg.h"
  50 #include "regdb.h"
  51 #include "nl80211.h"
  52
  53 #ifdef CONFIG_CFG80211_REG_DEBUG
  54 #define REG_DBG_PRINT(format, args...)                  \
  55         printk(KERN_DEBUG pr_fmt(format), ##args)
  56 #else
  57 #define REG_DBG_PRINT(args...)
  58 #endif
  59
  60 /* Receipt of information from last regulatory request */
  61 static struct regulatory_request *last_request;
  62
  63 /* To trigger userspace events */
  64 static struct platform_device *reg_pdev;
  65
  66 static struct device_type reg_device_type = {
  67         .uevent = reg_device_uevent,
  68 };
  69
  70 /*
  71  * Central wireless core regulatory domains, we only need two,
  72  * the current one and a world regulatory domain in case we have no
  73  * information to give us an alpha2
  74  */
  75 const struct ieee80211_regdomain *cfg80211_regdomain;
  76
  77 /*
  78  * Protects static reg.c components:
  79  *     - cfg80211_world_regdom
  80  *     - cfg80211_regdom
  81  *     - last_request
  82  */
  83 static DEFINE_MUTEX(reg_mutex);
  84
  85 static inline void assert_reg_lock(void)
  86 {
  87         lockdep_assert_held(&reg_mutex);
  88 }
  89
  90 /* Used to queue up regulatory hints */
  91 static LIST_HEAD(reg_requests_list);
  92 static spinlock_t reg_requests_lock;
  93
  94 /* Used to queue up beacon hints for review */
  95 static LIST_HEAD(reg_pending_beacons);
  96 static spinlock_t reg_pending_beacons_lock;
  97
  98 /* Used to keep track of processed beacon hints */
  99 static LIST_HEAD(reg_beacon_list);
 100
 101 struct reg_beacon {
 102         struct list_head list;
 103         struct ieee80211_channel chan;
 104 };
 105
 106 static void reg_todo(struct work_struct *work);
 107 static DECLARE_WORK(reg_work, reg_todo);
 108
 109 static void reg_timeout_work(struct work_struct *work);
 110 static DECLARE_DELAYED_WORK(reg_timeout, reg_timeout_work);
 111
 112 /* We keep a static world regulatory domain in case of the absence of CRDA */
 113 static const struct ieee80211_regdomain world_regdom = {
 114         .n_reg_rules = 5,
 115         .alpha2 =  "00",
 116         .reg_rules = {
 117                 /* IEEE 802.11b/g, channels 1..11 */
 118                 REG_RULE(2412-10, 2462+10, 40, 6, 20, 0),
 119                 /* IEEE 802.11b/g, channels 12..13. No HT40
 120                  * channel fits here. */
 121                 REG_RULE(2467-10, 2472+10, 20, 6, 20,
 122                         NL80211_RRF_PASSIVE_SCAN |
 123                         NL80211_RRF_NO_IBSS),
 124                 /* IEEE 802.11 channel 14 - Only JP enables
 125                  * this and for 802.11b only */
 126                 REG_RULE(2484-10, 2484+10, 20, 6, 20,
 127                         NL80211_RRF_PASSIVE_SCAN |
 128                         NL80211_RRF_NO_IBSS |
 129                         NL80211_RRF_NO_OFDM),
 130                 /* IEEE 802.11a, channel 36..48 */
 131                 REG_RULE(5180-10, 5240+10, 40, 6, 20,
 132                         NL80211_RRF_PASSIVE_SCAN |
 133                         NL80211_RRF_NO_IBSS),
 134
 135                 /* NB: 5260 MHz - 5700 MHz requies DFS */
 136
 137                 /* IEEE 802.11a, channel 149..165 */
 138                 REG_RULE(5745-10, 5825+10, 40, 6, 20,
 139                         NL80211_RRF_PASSIVE_SCAN |
 140                         NL80211_RRF_NO_IBSS),
 141         }
 142 };
 143
 144 static const struct ieee80211_regdomain *cfg80211_world_regdom =
 145         &world_regdom;
 146
 147 static char *ieee80211_regdom = "00";
 148 static char user_alpha2[2];
 149
 150 module_param(ieee80211_regdom, charp, 0444);
 151 MODULE_PARM_DESC(ieee80211_regdom, "IEEE 802.11 regulatory domain code");
 152
 153 static void reset_regdomains(void)
 154 {
 155         /* avoid freeing static information or freeing something twice */
 156         if (cfg80211_regdomain == cfg80211_world_regdom)
 157                 cfg80211_regdomain = NULL;
 158         if (cfg80211_world_regdom == &world_regdom)
 159                 cfg80211_world_regdom = NULL;
 160         if (cfg80211_regdomain == &world_regdom)
 161                 cfg80211_regdomain = NULL;
 162
 163         kfree(cfg80211_regdomain);
 164         kfree(cfg80211_world_regdom);
 165
 166         cfg80211_world_regdom = &world_regdom;
 167         cfg80211_regdomain = NULL;
 168 }
 169
 170 /*
 171  * Dynamic world regulatory domain requested by the wireless
 172  * core upon initialization
 173  */
 174 static void update_world_regdomain(const struct ieee80211_regdomain *rd)
 175 {
 176         BUG_ON(!last_request);
 177
 178         reset_regdomains();
 179
 180         cfg80211_world_regdom = rd;
 181         cfg80211_regdomain = rd;
 182 }
 183
 184 bool is_world_regdom(const char *alpha2)
 185 {
 186         if (!alpha2)
 187                 return false;
 188         if (alpha2[0] == '0' && alpha2[1] == '0')
 189                 return true;
 190         return false;
 191 }
 192
 193 static bool is_alpha2_set(const char *alpha2)
 194 {
 195         if (!alpha2)
 196                 return false;
 197         if (alpha2[0] != 0 && alpha2[1] != 0)
 198                 return true;
 199         return false;
 200 }
 201
 202 static bool is_unknown_alpha2(const char *alpha2)
 203 {
 204         if (!alpha2)
 205                 return false;
 206         /*
 207          * Special case where regulatory domain was built by driver
 208          * but a specific alpha2 cannot be determined
 209          */
 210         if (alpha2[0] == '9' && alpha2[1] == '9')
 211                 return true;
 212         return false;
 213 }
 214
 215 static bool is_intersected_alpha2(const char *alpha2)
 216 {
 217         if (!alpha2)
 218                 return false;
 219         /*
 220          * Special case where regulatory domain is the
 221          * result of an intersection between two regulatory domain
 222          * structures
 223          */
 224         if (alpha2[0] == '9' && alpha2[1] == '8')
 225                 return true;
 226         return false;
 227 }
 228
 229 static bool is_an_alpha2(const char *alpha2)
 230 {
 231         if (!alpha2)
 232                 return false;
 233         if (isalpha(alpha2[0]) && isalpha(alpha2[1]))
 234                 return true;
 235         return false;
 236 }
 237
 238 static bool alpha2_equal(const char *alpha2_x, const char *alpha2_y)
 239 {
 240         if (!alpha2_x || !alpha2_y)
 241                 return false;
 242         if (alpha2_x[0] == alpha2_y[0] &&
 243                 alpha2_x[1] == alpha2_y[1])
 244                 return true;
 245         return false;
 246 }
 247
 248 static bool regdom_changes(const char *alpha2)
 249 {
 250         assert_cfg80211_lock();
 251
 252         if (!cfg80211_regdomain)
 253                 return true;
 254         if (alpha2_equal(cfg80211_regdomain->alpha2, alpha2))
 255                 return false;
 256         return true;
 257 }
 258
 259 /*
 260  * The NL80211_REGDOM_SET_BY_USER regdom alpha2 is cached, this lets
 261  * you know if a valid regulatory hint with NL80211_REGDOM_SET_BY_USER
 262  * has ever been issued.
 263  */
 264 static bool is_user_regdom_saved(void)
 265 {
 266         if (user_alpha2[0] == '9' && user_alpha2[1] == '7')
 267                 return false;
 268
 269         /* This would indicate a mistake on the design */
 270         if (WARN((!is_world_regdom(user_alpha2) &&
 271                   !is_an_alpha2(user_alpha2)),
 272                  "Unexpected user alpha2: %c%c\n",
 273                  user_alpha2[0],
 274                  user_alpha2[1]))
 275                 return false;
 276
 277         return true;
 278 }
 279
 280 static int reg_copy_regd(const struct ieee80211_regdomain **dst_regd,
 281                          const struct ieee80211_regdomain *src_regd)
 282 {
 283         struct ieee80211_regdomain *regd;
 284         int size_of_regd = 0;
 285         unsigned int i;
 286
 287         size_of_regd = sizeof(struct ieee80211_regdomain) +
 288           ((src_regd->n_reg_rules + 1) * sizeof(struct ieee80211_reg_rule));
 289
 290         regd = kzalloc(size_of_regd, GFP_KERNEL);
 291         if (!regd)
 292                 return -ENOMEM;
 293
 294         memcpy(regd, src_regd, sizeof(struct ieee80211_regdomain));
 295
 296         for (i = 0; i < src_regd->n_reg_rules; i++)
 297                 memcpy(&regd->reg_rules[i], &src_regd->reg_rules[i],
 298                         sizeof(struct ieee80211_reg_rule));
 299
 300         *dst_regd = regd;
 301         return 0;
 302 }
 303
 304 #ifdef CONFIG_CFG80211_INTERNAL_REGDB
 305 struct reg_regdb_search_request {
 306         char alpha2[2];
 307         struct list_head list;
 308 };
 309
 310 static LIST_HEAD(reg_regdb_search_list);
 311 static DEFINE_MUTEX(reg_regdb_search_mutex);
 312
 313 static void reg_regdb_search(struct work_struct *work)
 314 {
 315         struct reg_regdb_search_request *request;
 316         const struct ieee80211_regdomain *curdom, *regdom;
 317         int i, r;
 318
 319         mutex_lock(&reg_regdb_search_mutex);
 320         while (!list_empty(&reg_regdb_search_list)) {
 321                 request = list_first_entry(&reg_regdb_search_list,
 322                                            struct reg_regdb_search_request,
 323                                            list);
 324                 list_del(&request->list);
 325
 326                 for (i=0; i<reg_regdb_size; i++) {
 327                         curdom = reg_regdb[i];
 328
 329                         if (!memcmp(request->alpha2, curdom->alpha2, 2)) {
 330                                 r = reg_copy_regd(&regdom, curdom);
 331                                 if (r)
 332                                         break;
 333                                 mutex_lock(&cfg80211_mutex);
 334                                 set_regdom(regdom);
 335                                 mutex_unlock(&cfg80211_mutex);
 336                                 break;
 337                         }
 338                 }
 339
 340                 kfree(request);
 341         }
 342         mutex_unlock(&reg_regdb_search_mutex);
 343 }
 344
 345 static DECLARE_WORK(reg_regdb_work, reg_regdb_search);
 346
 347 static void reg_regdb_query(const char *alpha2)
 348 {
 349         struct reg_regdb_search_request *request;
 350
 351         if (!alpha2)
 352                 return;
 353
 354         request = kzalloc(sizeof(struct reg_regdb_search_request), GFP_KERNEL);
 355         if (!request)
 356                 return;
 357
 358         memcpy(request->alpha2, alpha2, 2);
 359
 360         mutex_lock(&reg_regdb_search_mutex);
 361         list_add_tail(&request->list, &reg_regdb_search_list);
 362         mutex_unlock(&reg_regdb_search_mutex);
 363
 364         schedule_work(&reg_regdb_work);
 365 }
 366 #else
 367 static inline void reg_regdb_query(const char *alpha2) {}
 368 #endif /* CONFIG_CFG80211_INTERNAL_REGDB */
 369
 370 /*
 371  * This lets us keep regulatory code which is updated on a regulatory
 372  * basis in userspace. Country information is filled in by
 373  * reg_device_uevent
 374  */
 375 static int call_crda(const char *alpha2)
 376 {
 377         if (!is_world_regdom((char *) alpha2))
 378                 pr_info("Calling CRDA for country: %c%c\n",
 379                         alpha2[0], alpha2[1]);
 380         else
 381                 pr_info("Calling CRDA to update world regulatory domain\n");
 382
 383         /* query internal regulatory database (if it exists) */
 384         reg_regdb_query(alpha2);
 385
 386         return kobject_uevent(&reg_pdev->dev.kobj, KOBJ_CHANGE);
 387 }
 388
 389 /* Used by nl80211 before kmalloc'ing our regulatory domain */
 390 bool reg_is_valid_request(const char *alpha2)
 391 {
 392         assert_cfg80211_lock();
 393
 394         if (!last_request)
 395                 return false;
 396
 397         return alpha2_equal(last_request->alpha2, alpha2);
 398 }
 399
 400 /* Sanity check on a regulatory rule */
 401 static bool is_valid_reg_rule(const struct ieee80211_reg_rule *rule)
 402 {
 403         const struct ieee80211_freq_range *freq_range = &rule->freq_range;
 404         u32 freq_diff;
 405
 406         if (freq_range->start_freq_khz <= 0 || freq_range->end_freq_khz <= 0)
 407                 return false;
 408
 409         if (freq_range->start_freq_khz > freq_range->end_freq_khz)
 410                 return false;
 411
 412         freq_diff = freq_range->end_freq_khz - freq_range->start_freq_khz;
 413
 414         if (freq_range->end_freq_khz <= freq_range->start_freq_khz ||
 415                         freq_range->max_bandwidth_khz > freq_diff)
 416                 return false;
 417
 418         return true;
 419 }
 420
 421 static bool is_valid_rd(const struct ieee80211_regdomain *rd)
 422 {
 423         const struct ieee80211_reg_rule *reg_rule = NULL;
 424         unsigned int i;
 425
 426         if (!rd->n_reg_rules)
 427                 return false;
 428
 429         if (WARN_ON(rd->n_reg_rules > NL80211_MAX_SUPP_REG_RULES))
 430                 return false;
 431
 432         for (i = 0; i < rd->n_reg_rules; i++) {
 433                 reg_rule = &rd->reg_rules[i];
 434                 if (!is_valid_reg_rule(reg_rule))
 435                         return false;
 436         }
 437
 438         return true;
 439 }
 440
 441 static bool reg_does_bw_fit(const struct ieee80211_freq_range *freq_range,
 442                             u32 center_freq_khz,
 443                             u32 bw_khz)
 444 {
 445         u32 start_freq_khz, end_freq_khz;
 446
 447         start_freq_khz = center_freq_khz - (bw_khz/2);
 448         end_freq_khz = center_freq_khz + (bw_khz/2);
 449
 450         if (start_freq_khz >= freq_range->start_freq_khz &&
 451             end_freq_khz <= freq_range->end_freq_khz)
 452                 return true;
 453
 454         return false;
 455 }
 456
 457 /**
 458  * freq_in_rule_band - tells us if a frequency is in a frequency band
 459  * @freq_range: frequency rule we want to query
 460  * @freq_khz: frequency we are inquiring about
 461  *
 462  * This lets us know if a specific frequency rule is or is not relevant to
 463  * a specific frequency's band. Bands are device specific and artificial
 464  * definitions (the "2.4 GHz band" and the "5 GHz band"), however it is
 465  * safe for now to assume that a frequency rule should not be part of a
 466  * frequency's band if the start freq or end freq are off by more than 2 GHz.
 467  * This resolution can be lowered and should be considered as we add
 468  * regulatory rule support for other "bands".
 469  **/
 470 static bool freq_in_rule_band(const struct ieee80211_freq_range *freq_range,
 471         u32 freq_khz)
 472 {
 473 #define ONE_GHZ_IN_KHZ  1000000
 474         if (abs(freq_khz - freq_range->start_freq_khz) <= (2 * ONE_GHZ_IN_KHZ))
 475                 return true;
 476         if (abs(freq_khz - freq_range->end_freq_khz) <= (2 * ONE_GHZ_IN_KHZ))
 477                 return true;
 478         return false;
 479 #undef ONE_GHZ_IN_KHZ
 480 }
 481
 482 /*
 483  * Helper for regdom_intersect(), this does the real
 484  * mathematical intersection fun
 485  */
 486 static int reg_rules_intersect(
 487         const struct ieee80211_reg_rule *rule1,
 488         const struct ieee80211_reg_rule *rule2,
 489         struct ieee80211_reg_rule *intersected_rule)
 490 {
 491         const struct ieee80211_freq_range *freq_range1, *freq_range2;
 492         struct ieee80211_freq_range *freq_range;
 493         const struct ieee80211_power_rule *power_rule1, *power_rule2;
 494         struct ieee80211_power_rule *power_rule;
 495         u32 freq_diff;
 496
 497         freq_range1 = &rule1->freq_range;
 498         freq_range2 = &rule2->freq_range;
 499         freq_range = &intersected_rule->freq_range;
 500
 501         power_rule1 = &rule1->power_rule;
 502         power_rule2 = &rule2->power_rule;
 503         power_rule = &intersected_rule->power_rule;
 504
 505         freq_range->start_freq_khz = max(freq_range1->start_freq_khz,
 506                 freq_range2->start_freq_khz);
 507         freq_range->end_freq_khz = min(freq_range1->end_freq_khz,
 508                 freq_range2->end_freq_khz);
 509         freq_range->max_bandwidth_khz = min(freq_range1->max_bandwidth_khz,
 510                 freq_range2->max_bandwidth_khz);
 511
 512         freq_diff = freq_range->end_freq_khz - freq_range->start_freq_khz;
 513         if (freq_range->max_bandwidth_khz > freq_diff)
 514                 freq_range->max_bandwidth_khz = freq_diff;
 515
 516         power_rule->max_eirp = min(power_rule1->max_eirp,
 517                 power_rule2->max_eirp);
 518         power_rule->max_antenna_gain = min(power_rule1->max_antenna_gain,
 519                 power_rule2->max_antenna_gain);
 520
 521         intersected_rule->flags = (rule1->flags | rule2->flags);
 522
 523         if (!is_valid_reg_rule(intersected_rule))
 524                 return -EINVAL;
 525
 526         return 0;
 527 }
 528
 529 /**
 530  * regdom_intersect - do the intersection between two regulatory domains
 531  * @rd1: first regulatory domain
 532  * @rd2: second regulatory domain
 533  *
 534  * Use this function to get the intersection between two regulatory domains.
 535  * Once completed we will mark the alpha2 for the rd as intersected, "98",
 536  * as no one single alpha2 can represent this regulatory domain.
 537  *
 538  * Returns a pointer to the regulatory domain structure which will hold the
 539  * resulting intersection of rules between rd1 and rd2. We will
 540  * kzalloc() this structure for you.
 541  */
 542 static struct ieee80211_regdomain *regdom_intersect(
 543         const struct ieee80211_regdomain *rd1,
 544         const struct ieee80211_regdomain *rd2)
 545 {
 546         int r, size_of_regd;
 547         unsigned int x, y;
 548         unsigned int num_rules = 0, rule_idx = 0;
 549         const struct ieee80211_reg_rule *rule1, *rule2;
 550         struct ieee80211_reg_rule *intersected_rule;
 551         struct ieee80211_regdomain *rd;
 552         /* This is just a dummy holder to help us count */
 553         struct ieee80211_reg_rule irule;
 554
 555         /* Uses the stack temporarily for counter arithmetic */
 556         intersected_rule = &irule;
 557
 558         memset(intersected_rule, 0, sizeof(struct ieee80211_reg_rule));
 559
 560         if (!rd1 || !rd2)
 561                 return NULL;
 562
 563         /*
 564          * First we get a count of the rules we'll need, then we actually
 565          * build them. This is to so we can malloc() and free() a
 566          * regdomain once. The reason we use reg_rules_intersect() here
 567          * is it will return -EINVAL if the rule computed makes no sense.
 568          * All rules that do check out OK are valid.
 569          */
 570
 571         for (x = 0; x < rd1->n_reg_rules; x++) {
 572                 rule1 = &rd1->reg_rules[x];
 573                 for (y = 0; y < rd2->n_reg_rules; y++) {
 574                         rule2 = &rd2->reg_rules[y];
 575                         if (!reg_rules_intersect(rule1, rule2,
 576                                         intersected_rule))
 577                                 num_rules++;
 578                         memset(intersected_rule, 0,
 579                                         sizeof(struct ieee80211_reg_rule));
 580                 }
 581         }
 582
 583         if (!num_rules)
 584                 return NULL;
 585
 586         size_of_regd = sizeof(struct ieee80211_regdomain) +
 587                 ((num_rules + 1) * sizeof(struct ieee80211_reg_rule));
 588
 589         rd = kzalloc(size_of_regd, GFP_KERNEL);
 590         if (!rd)
 591                 return NULL;
 592
 593         for (x = 0; x < rd1->n_reg_rules; x++) {
 594                 rule1 = &rd1->reg_rules[x];
 595                 for (y = 0; y < rd2->n_reg_rules; y++) {
 596                         rule2 = &rd2->reg_rules[y];
 597                         /*
 598                          * This time around instead of using the stack lets
 599                          * write to the target rule directly saving ourselves
 600                          * a memcpy()
 601                          */
 602                         intersected_rule = &rd->reg_rules[rule_idx];
 603                         r = reg_rules_intersect(rule1, rule2,
 604                                 intersected_rule);
 605                         /*
 606                          * No need to memset here the intersected rule here as
 607                          * we're not using the stack anymore
 608                          */
 609                         if (r)
 610                                 continue;
 611                         rule_idx++;
 612                 }
 613         }
 614
 615         if (rule_idx != num_rules) {
 616                 kfree(rd);
 617                 return NULL;
 618         }
 619
 620         rd->n_reg_rules = num_rules;
 621         rd->alpha2[0] = '9';
 622         rd->alpha2[1] = '8';
 623
 624         return rd;
 625 }
 626
 627 /*
 628  * XXX: add support for the rest of enum nl80211_reg_rule_flags, we may
 629  * want to just have the channel structure use these
 630  */
 631 static u32 map_regdom_flags(u32 rd_flags)
 632 {
 633         u32 channel_flags = 0;
 634         if (rd_flags & NL80211_RRF_PASSIVE_SCAN)
 635                 channel_flags |= IEEE80211_CHAN_PASSIVE_SCAN;
 636         if (rd_flags & NL80211_RRF_NO_IBSS)
 637                 channel_flags |= IEEE80211_CHAN_NO_IBSS;
 638         if (rd_flags & NL80211_RRF_DFS)
 639                 channel_flags |= IEEE80211_CHAN_RADAR;
 640         return channel_flags;
 641 }
 642
 643 static int freq_reg_info_regd(struct wiphy *wiphy,
 644                               u32 center_freq,
 645                               u32 desired_bw_khz,
 646                               const struct ieee80211_reg_rule **reg_rule,
 647                               const struct ieee80211_regdomain *custom_regd)
 648 {
 649         int i;
 650         bool band_rule_found = false;
 651         const struct ieee80211_regdomain *regd;
 652         bool bw_fits = false;
 653
 654         if (!desired_bw_khz)
 655                 desired_bw_khz = MHZ_TO_KHZ(20);
 656
 657         regd = custom_regd ? custom_regd : cfg80211_regdomain;
 658
 659         /*
 660          * Follow the driver's regulatory domain, if present, unless a country
 661          * IE has been processed or a user wants to help complaince further
 662          */
 663         if (!custom_regd &&
 664             last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE &&
 665             last_request->initiator != NL80211_REGDOM_SET_BY_USER &&
 666             wiphy->regd)
 667                 regd = wiphy->regd;
 668
 669         if (!regd)
 670                 return -EINVAL;
 671
 672         for (i = 0; i < regd->n_reg_rules; i++) {
 673                 const struct ieee80211_reg_rule *rr;
 674                 const struct ieee80211_freq_range *fr = NULL;
 675
 676                 rr = &regd->reg_rules[i];
 677                 fr = &rr->freq_range;
 678
 679                 /*
 680                  * We only need to know if one frequency rule was
 681                  * was in center_freq's band, that's enough, so lets
 682                  * not overwrite it once found
 683                  */
 684                 if (!band_rule_found)
 685                         band_rule_found = freq_in_rule_band(fr, center_freq);
 686
 687                 bw_fits = reg_does_bw_fit(fr,
 688                                           center_freq,
 689                                           desired_bw_khz);
 690
 691                 if (band_rule_found && bw_fits) {
 692                         *reg_rule = rr;
 693                         return 0;
 694                 }
 695         }
 696
 697         if (!band_rule_found)
 698                 return -ERANGE;
 699
 700         return -EINVAL;
 701 }
 702
 703 int freq_reg_info(struct wiphy *wiphy,
 704                   u32 center_freq,
 705                   u32 desired_bw_khz,
 706                   const struct ieee80211_reg_rule **reg_rule)
 707 {
 708         assert_cfg80211_lock();
 709         return freq_reg_info_regd(wiphy,
 710                                   center_freq,
 711                                   desired_bw_khz,
 712                                   reg_rule,
 713                                   NULL);
 714 }
 715 EXPORT_SYMBOL(freq_reg_info);
 716
 717 #ifdef CONFIG_CFG80211_REG_DEBUG
 718 static const char *reg_initiator_name(enum nl80211_reg_initiator initiator)
 719 {
 720         switch (initiator) {
 721         case NL80211_REGDOM_SET_BY_CORE:
 722                 return "Set by core";
 723         case NL80211_REGDOM_SET_BY_USER:
 724                 return "Set by user";
 725         case NL80211_REGDOM_SET_BY_DRIVER:
 726                 return "Set by driver";
 727         case NL80211_REGDOM_SET_BY_COUNTRY_IE:
 728                 return "Set by country IE";
 729         default:
 730                 WARN_ON(1);
 731                 return "Set by bug";
 732         }
 733 }
 734
 735 static void chan_reg_rule_print_dbg(struct ieee80211_channel *chan,
 736                                     u32 desired_bw_khz,
 737                                     const struct ieee80211_reg_rule *reg_rule)
 738 {
 739         const struct ieee80211_power_rule *power_rule;
 740         const struct ieee80211_freq_range *freq_range;
 741         char max_antenna_gain[32];
 742
 743         power_rule = &reg_rule->power_rule;
 744         freq_range = &reg_rule->freq_range;
 745
 746         if (!power_rule->max_antenna_gain)
 747                 snprintf(max_antenna_gain, 32, "N/A");
 748         else
 749                 snprintf(max_antenna_gain, 32, "%d", power_rule->max_antenna_gain);
 750
 751         REG_DBG_PRINT("Updating information on frequency %d MHz "
 752                       "for a %d MHz width channel with regulatory rule:\n",
 753                       chan->center_freq,
 754                       KHZ_TO_MHZ(desired_bw_khz));
 755
 756         REG_DBG_PRINT("%d KHz - %d KHz @ %d KHz), (%s mBi, %d mBm)\n",
 757                       freq_range->start_freq_khz,
 758                       freq_range->end_freq_khz,
 759                       freq_range->max_bandwidth_khz,
 760                       max_antenna_gain,
 761                       power_rule->max_eirp);
 762 }
 763 #else
 764 static void chan_reg_rule_print_dbg(struct ieee80211_channel *chan,
 765                                     u32 desired_bw_khz,
 766                                     const struct ieee80211_reg_rule *reg_rule)
 767 {
 768         return;
 769 }
 770 #endif
 771
 772 /*
 773  * Note that right now we assume the desired channel bandwidth
 774  * is always 20 MHz for each individual channel (HT40 uses 20 MHz
 775  * per channel, the primary and the extension channel). To support
 776  * smaller custom bandwidths such as 5 MHz or 10 MHz we'll need a
 777  * new ieee80211_channel.target_bw and re run the regulatory check
 778  * on the wiphy with the target_bw specified. Then we can simply use
 779  * that below for the desired_bw_khz below.
 780  */
 781 static void handle_channel(struct wiphy *wiphy,
 782                            enum nl80211_reg_initiator initiator,
 783                            enum ieee80211_band band,
 784                            unsigned int chan_idx)
 785 {
 786         int r;
 787         u32 flags, bw_flags = 0;
 788         u32 desired_bw_khz = MHZ_TO_KHZ(20);
 789         const struct ieee80211_reg_rule *reg_rule = NULL;
 790         const struct ieee80211_power_rule *power_rule = NULL;
 791         const struct ieee80211_freq_range *freq_range = NULL;
 792         struct ieee80211_supported_band *sband;
 793         struct ieee80211_channel *chan;
 794         struct wiphy *request_wiphy = NULL;
 795
 796         assert_cfg80211_lock();
 797
 798         request_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);
 799
 800         sband = wiphy->bands[band];
 801         BUG_ON(chan_idx >= sband->n_channels);
 802         chan = &sband->channels[chan_idx];
 803
 804         flags = chan->orig_flags;
 805
 806         r = freq_reg_info(wiphy,
 807                           MHZ_TO_KHZ(chan->center_freq),
 808                           desired_bw_khz,
 809                           &reg_rule);
 810
 811         if (r) {
 812                 /*
 813                  * We will disable all channels that do not match our
 814                  * received regulatory rule unless the hint is coming
 815                  * from a Country IE and the Country IE had no information
 816                  * about a band. The IEEE 802.11 spec allows for an AP
 817                  * to send only a subset of the regulatory rules allowed,
 818                  * so an AP in the US that only supports 2.4 GHz may only send
 819                  * a country IE with information for the 2.4 GHz band
 820                  * while 5 GHz is still supported.
 821                  */
 822                 if (initiator == NL80211_REGDOM_SET_BY_COUNTRY_IE &&
 823                     r == -ERANGE)
 824                         return;
 825
 826                 REG_DBG_PRINT("Disabling freq %d MHz\n", chan->center_freq);
 827                 chan->flags = IEEE80211_CHAN_DISABLED;
 828                 return;
 829         }
 830
 831         chan_reg_rule_print_dbg(chan, desired_bw_khz, reg_rule);
 832
 833         power_rule = &reg_rule->power_rule;
 834         freq_range = &reg_rule->freq_range;
 835
 836         if (freq_range->max_bandwidth_khz < MHZ_TO_KHZ(40))
 837                 bw_flags = IEEE80211_CHAN_NO_HT40;
 838
 839         if (last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER &&
 840             request_wiphy && request_wiphy == wiphy &&
 841             request_wiphy->flags & WIPHY_FLAG_STRICT_REGULATORY) {
 842                 /*
 843                  * This guarantees the driver's requested regulatory domain
 844                  * will always be used as a base for further regulatory
 845                  * settings
 846                  */
 847                 chan->flags = chan->orig_flags =
 848                         map_regdom_flags(reg_rule->flags) | bw_flags;
 849                 chan->max_antenna_gain = chan->orig_mag =
 850                         (int) MBI_TO_DBI(power_rule->max_antenna_gain);
 851                 chan->max_power = chan->orig_mpwr =
 852                         (int) MBM_TO_DBM(power_rule->max_eirp);
 853                 return;
 854         }
 855
 856         chan->beacon_found = false;
 857         chan->flags = flags | bw_flags | map_regdom_flags(reg_rule->flags);
 858         chan->max_antenna_gain = min(chan->orig_mag,
 859                 (int) MBI_TO_DBI(power_rule->max_antenna_gain));
 860         if (chan->orig_mpwr)
 861                 chan->max_power = min(chan->orig_mpwr,
 862                         (int) MBM_TO_DBM(power_rule->max_eirp));
 863         else
 864                 chan->max_power = (int) MBM_TO_DBM(power_rule->max_eirp);
 865 }
 866
 867 static void handle_band(struct wiphy *wiphy,
 868                         enum ieee80211_band band,
 869                         enum nl80211_reg_initiator initiator)
 870 {
 871         unsigned int i;
 872         struct ieee80211_supported_band *sband;
 873
 874         BUG_ON(!wiphy->bands[band]);
 875         sband = wiphy->bands[band];
 876
 877         for (i = 0; i < sband->n_channels; i++)
 878                 handle_channel(wiphy, initiator, band, i);
 879 }
 880
 881 static bool ignore_reg_update(struct wiphy *wiphy,
 882                               enum nl80211_reg_initiator initiator)
 883 {
 884         if (!last_request) {
 885                 REG_DBG_PRINT("Ignoring regulatory request %s since "
 886                               "last_request is not set\n",
 887                               reg_initiator_name(initiator));
 888                 return true;
 889         }
 890
 891         if (initiator == NL80211_REGDOM_SET_BY_CORE &&
 892             wiphy->flags & WIPHY_FLAG_CUSTOM_REGULATORY) {
 893                 REG_DBG_PRINT("Ignoring regulatory request %s "
 894                               "since the driver uses its own custom "
 895                               "regulatory domain\n",
 896                               reg_initiator_name(initiator));
 897                 return true;
 898         }
 899
 900         /*
 901          * wiphy->regd will be set once the device has its own
 902          * desired regulatory domain set
 903          */
 904         if (wiphy->flags & WIPHY_FLAG_STRICT_REGULATORY && !wiphy->regd &&
 905             initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE &&
 906             !is_world_regdom(last_request->alpha2)) {
 907                 REG_DBG_PRINT("Ignoring regulatory request %s "
 908                               "since the driver requires its own regulatory "
 909                               "domain to be set first\n",
 910                               reg_initiator_name(initiator));
 911                 return true;
 912         }
 913
 914         return false;
 915 }
 916
 917 static void handle_reg_beacon(struct wiphy *wiphy,
 918                               unsigned int chan_idx,
 919                               struct reg_beacon *reg_beacon)
 920 {
 921         struct ieee80211_supported_band *sband;
 922         struct ieee80211_channel *chan;
 923         bool channel_changed = false;
 924         struct ieee80211_channel chan_before;
 925
 926         assert_cfg80211_lock();
 927
 928         sband = wiphy->bands[reg_beacon->chan.band];
 929         chan = &sband->channels[chan_idx];
 930
 931         if (likely(chan->center_freq != reg_beacon->chan.center_freq))
 932                 return;
 933
 934         if (chan->beacon_found)
 935                 return;
 936
 937         chan->beacon_found = true;
 938
 939         if (wiphy->flags & WIPHY_FLAG_DISABLE_BEACON_HINTS)
 940                 return;
 941
 942         chan_before.center_freq = chan->center_freq;
 943         chan_before.flags = chan->flags;
 944
 945         if (chan->flags & IEEE80211_CHAN_PASSIVE_SCAN) {
 946                 chan->flags &= ~IEEE80211_CHAN_PASSIVE_SCAN;
 947                 channel_changed = true;
 948         }
 949
 950         if (chan->flags & IEEE80211_CHAN_NO_IBSS) {
 951                 chan->flags &= ~IEEE80211_CHAN_NO_IBSS;
 952                 channel_changed = true;
 953         }
 954
 955         if (channel_changed)
 956                 nl80211_send_beacon_hint_event(wiphy, &chan_before, chan);
 957 }
 958
 959 /*
 960  * Called when a scan on a wiphy finds a beacon on
 961  * new channel
 962  */
 963 static void wiphy_update_new_beacon(struct wiphy *wiphy,
 964                                     struct reg_beacon *reg_beacon)
 965 {
 966         unsigned int i;
 967         struct ieee80211_supported_band *sband;
 968
 969         assert_cfg80211_lock();
 970
 971         if (!wiphy->bands[reg_beacon->chan.band])
 972                 return;
 973
 974         sband = wiphy->bands[reg_beacon->chan.band];
 975
 976         for (i = 0; i < sband->n_channels; i++)
 977                 handle_reg_beacon(wiphy, i, reg_beacon);
 978 }
 979
 980 /*
 981  * Called upon reg changes or a new wiphy is added
 982  */
 983 static void wiphy_update_beacon_reg(struct wiphy *wiphy)
 984 {
 985         unsigned int i;
 986         struct ieee80211_supported_band *sband;
 987         struct reg_beacon *reg_beacon;
 988
 989         assert_cfg80211_lock();
 990
 991         if (list_empty(&reg_beacon_list))
 992                 return;
 993
 994         list_for_each_entry(reg_beacon, &reg_beacon_list, list) {
 995                 if (!wiphy->bands[reg_beacon->chan.band])
 996                         continue;
 997                 sband = wiphy->bands[reg_beacon->chan.band];
 998                 for (i = 0; i < sband->n_channels; i++)
 999                         handle_reg_beacon(wiphy, i, reg_beacon);
1000         }
1001 }
1002
1003 static bool reg_is_world_roaming(struct wiphy *wiphy)
1004 {
1005         if (is_world_regdom(cfg80211_regdomain->alpha2) ||
1006             (wiphy->regd && is_world_regdom(wiphy->regd->alpha2)))
1007                 return true;
1008         if (last_request &&
1009             last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE &&
1010             wiphy->flags & WIPHY_FLAG_CUSTOM_REGULATORY)
1011                 return true;
1012         return false;
1013 }
1014
1015 /* Reap the advantages of previously found beacons */
1016 static void reg_process_beacons(struct wiphy *wiphy)
1017 {
1018         /*
1019          * Means we are just firing up cfg80211, so no beacons would
1020          * have been processed yet.
1021          */
1022         if (!last_request)
1023                 return;
1024         if (!reg_is_world_roaming(wiphy))
1025                 return;
1026         wiphy_update_beacon_reg(wiphy);
1027 }
1028
1029 static bool is_ht40_not_allowed(struct ieee80211_channel *chan)
1030 {
1031         if (!chan)
1032                 return true;
1033         if (chan->flags & IEEE80211_CHAN_DISABLED)
1034                 return true;
1035         /* This would happen when regulatory rules disallow HT40 completely */
1036         if (IEEE80211_CHAN_NO_HT40 == (chan->flags & (IEEE80211_CHAN_NO_HT40)))
1037                 return true;
1038         return false;
1039 }
1040
1041 static void reg_process_ht_flags_channel(struct wiphy *wiphy,
1042                                          enum ieee80211_band band,
1043                                          unsigned int chan_idx)
1044 {
1045         struct ieee80211_supported_band *sband;
1046         struct ieee80211_channel *channel;
1047         struct ieee80211_channel *channel_before = NULL, *channel_after = NULL;
1048         unsigned int i;
1049
1050         assert_cfg80211_lock();
1051
1052         sband = wiphy->bands[band];
1053         BUG_ON(chan_idx >= sband->n_channels);
1054         channel = &sband->channels[chan_idx];
1055
1056         if (is_ht40_not_allowed(channel)) {
1057                 channel->flags |= IEEE80211_CHAN_NO_HT40;
1058                 return;
1059         }
1060
1061         /*
1062          * We need to ensure the extension channels exist to
1063          * be able to use HT40- or HT40+, this finds them (or not)
1064          */
1065         for (i = 0; i < sband->n_channels; i++) {
1066                 struct ieee80211_channel *c = &sband->channels[i];
1067                 if (c->center_freq == (channel->center_freq - 20))
1068                         channel_before = c;
1069                 if (c->center_freq == (channel->center_freq + 20))
1070                         channel_after = c;
1071         }
1072
1073         /*
1074          * Please note that this assumes target bandwidth is 20 MHz,
1075          * if that ever changes we also need to change the below logic
1076          * to include that as well.
1077          */
1078         if (is_ht40_not_allowed(channel_before))
1079                 channel->flags |= IEEE80211_CHAN_NO_HT40MINUS;
1080         else
1081                 channel->flags &= ~IEEE80211_CHAN_NO_HT40MINUS;
1082
1083         if (is_ht40_not_allowed(channel_after))
1084                 channel->flags |= IEEE80211_CHAN_NO_HT40PLUS;
1085         else
1086                 channel->flags &= ~IEEE80211_CHAN_NO_HT40PLUS;
1087 }
1088
1089 static void reg_process_ht_flags_band(struct wiphy *wiphy,
1090                                       enum ieee80211_band band)
1091 {
1092         unsigned int i;
1093         struct ieee80211_supported_band *sband;
1094
1095         BUG_ON(!wiphy->bands[band]);
1096         sband = wiphy->bands[band];
1097
1098         for (i = 0; i < sband->n_channels; i++)
1099                 reg_process_ht_flags_channel(wiphy, band, i);
1100 }
1101
1102 static void reg_process_ht_flags(struct wiphy *wiphy)
1103 {
1104         enum ieee80211_band band;
1105
1106         if (!wiphy)
1107                 return;
1108
1109         for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
1110                 if (wiphy->bands[band])
1111                         reg_process_ht_flags_band(wiphy, band);
1112         }
1113
1114 }
1115
1116 static void wiphy_update_regulatory(struct wiphy *wiphy,
1117                                     enum nl80211_reg_initiator initiator)
1118 {
1119         enum ieee80211_band band;
1120
1121         assert_reg_lock();
1122
1123         if (ignore_reg_update(wiphy, initiator))
1124                 return;
1125
1126         for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
1127                 if (wiphy->bands[band])
1128                         handle_band(wiphy, band, initiator);
1129         }
1130
1131         reg_process_beacons(wiphy);
1132         reg_process_ht_flags(wiphy);
1133         if (wiphy->reg_notifier)
1134                 wiphy->reg_notifier(wiphy, last_request);
1135 }
1136
1137 void regulatory_update(struct wiphy *wiphy,
1138                        enum nl80211_reg_initiator setby)
1139 {
1140         mutex_lock(&reg_mutex);
1141         wiphy_update_regulatory(wiphy, setby);
1142         mutex_unlock(&reg_mutex);
1143 }
1144
1145 static void update_all_wiphy_regulatory(enum nl80211_reg_initiator initiator)
1146 {
1147         struct cfg80211_registered_device *rdev;
1148
1149         list_for_each_entry(rdev, &cfg80211_rdev_list, list)
1150                 wiphy_update_regulatory(&rdev->wiphy, initiator);
1151 }
1152
1153 static void handle_channel_custom(struct wiphy *wiphy,
1154                                   enum ieee80211_band band,
1155                                   unsigned int chan_idx,
1156                                   const struct ieee80211_regdomain *regd)
1157 {
1158         int r;
1159         u32 desired_bw_khz = MHZ_TO_KHZ(20);
1160         u32 bw_flags = 0;
1161         const struct ieee80211_reg_rule *reg_rule = NULL;
1162         const struct ieee80211_power_rule *power_rule = NULL;
1163         const struct ieee80211_freq_range *freq_range = NULL;
1164         struct ieee80211_supported_band *sband;
1165         struct ieee80211_channel *chan;
1166
1167         assert_reg_lock();
1168
1169         sband = wiphy->bands[band];
1170         BUG_ON(chan_idx >= sband->n_channels);
1171         chan = &sband->channels[chan_idx];
1172
1173         r = freq_reg_info_regd(wiphy,
1174                                MHZ_TO_KHZ(chan->center_freq),
1175                                desired_bw_khz,
1176                                &reg_rule,
1177                                regd);
1178
1179         if (r) {
1180                 REG_DBG_PRINT("Disabling freq %d MHz as custom "
1181                               "regd has no rule that fits a %d MHz "
1182                               "wide channel\n",
1183                               chan->center_freq,
1184                               KHZ_TO_MHZ(desired_bw_khz));
1185                 chan->flags = IEEE80211_CHAN_DISABLED;
1186                 return;
1187         }
1188
1189         chan_reg_rule_print_dbg(chan, desired_bw_khz, reg_rule);
1190
1191         power_rule = &reg_rule->power_rule;
1192         freq_range = &reg_rule->freq_range;
1193
1194         if (freq_range->max_bandwidth_khz < MHZ_TO_KHZ(40))
1195                 bw_flags = IEEE80211_CHAN_NO_HT40;
1196
1197         chan->flags |= map_regdom_flags(reg_rule->flags) | bw_flags;
1198         chan->max_antenna_gain = (int) MBI_TO_DBI(power_rule->max_antenna_gain);
1199         chan->max_power = (int) MBM_TO_DBM(power_rule->max_eirp);
1200 }
1201
1202 static void handle_band_custom(struct wiphy *wiphy, enum ieee80211_band band,
1203                                const struct ieee80211_regdomain *regd)
1204 {
1205         unsigned int i;
1206         struct ieee80211_supported_band *sband;
1207
1208         BUG_ON(!wiphy->bands[band]);
1209         sband = wiphy->bands[band];
1210
1211         for (i = 0; i < sband->n_channels; i++)
1212                 handle_channel_custom(wiphy, band, i, regd);
1213 }
1214
1215 /* Used by drivers prior to wiphy registration */
1216 void wiphy_apply_custom_regulatory(struct wiphy *wiphy,
1217                                    const struct ieee80211_regdomain *regd)
1218 {
1219         enum ieee80211_band band;
1220         unsigned int bands_set = 0;
1221
1222         mutex_lock(&reg_mutex);
1223         for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
1224                 if (!wiphy->bands[band])
1225                         continue;
1226                 handle_band_custom(wiphy, band, regd);
1227                 bands_set++;
1228         }
1229         mutex_unlock(&reg_mutex);
1230
1231         /*
1232          * no point in calling this if it won't have any effect
1233          * on your device's supportd bands.
1234          */
1235         WARN_ON(!bands_set);
1236 }
1237 EXPORT_SYMBOL(wiphy_apply_custom_regulatory);
1238
1239 /*
1240  * Return value which can be used by ignore_request() to indicate
1241  * it has been determined we should intersect two regulatory domains
1242  */
1243 #define REG_INTERSECT   1
1244
1245 /* This has the logic which determines when a new request
1246  * should be ignored. */
1247 static int ignore_request(struct wiphy *wiphy,
1248                           struct regulatory_request *pending_request)
1249 {
1250         struct wiphy *last_wiphy = NULL;
1251
1252         assert_cfg80211_lock();
1253
1254         /* All initial requests are respected */
1255         if (!last_request)
1256                 return 0;
1257
1258         switch (pending_request->initiator) {
1259         case NL80211_REGDOM_SET_BY_CORE:
1260                 return 0;
1261         case NL80211_REGDOM_SET_BY_COUNTRY_IE:
1262
1263                 last_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);
1264
1265                 if (unlikely(!is_an_alpha2(pending_request->alpha2)))
1266                         return -EINVAL;
1267                 if (last_request->initiator ==
1268                     NL80211_REGDOM_SET_BY_COUNTRY_IE) {
1269                         if (last_wiphy != wiphy) {
1270                                 /*
1271                                  * Two cards with two APs claiming different
1272                                  * Country IE alpha2s. We could
1273                                  * intersect them, but that seems unlikely
1274                                  * to be correct. Reject second one for now.
1275                                  */
1276                                 if (regdom_changes(pending_request->alpha2))
1277                                         return -EOPNOTSUPP;
1278                                 return -EALREADY;
1279                         }
1280                         /*
1281                          * Two consecutive Country IE hints on the same wiphy.
1282                          * This should be picked up early by the driver/stack
1283                          */
1284                         if (WARN_ON(regdom_changes(pending_request->alpha2)))
1285                                 return 0;
1286                         return -EALREADY;
1287                 }
1288                 return 0;
1289         case NL80211_REGDOM_SET_BY_DRIVER:
1290                 if (last_request->initiator == NL80211_REGDOM_SET_BY_CORE) {
1291                         if (regdom_changes(pending_request->alpha2))
1292                                 return 0;
1293                         return -EALREADY;
1294                 }
1295
1296                 /*
1297                  * This would happen if you unplug and plug your card
1298                  * back in or if you add a new device for which the previously
1299                  * loaded card also agrees on the regulatory domain.
1300                  */
1301                 if (last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER &&
1302                     !regdom_changes(pending_request->alpha2))
1303                         return -EALREADY;
1304
1305                 return REG_INTERSECT;
1306         case NL80211_REGDOM_SET_BY_USER:
1307                 if (last_request->initiator == NL80211_REGDOM_SET_BY_COUNTRY_IE)
1308                         return REG_INTERSECT;
1309                 /*
1310                  * If the user knows better the user should set the regdom
1311                  * to their country before the IE is picked up
1312                  */
1313                 if (last_request->initiator == NL80211_REGDOM_SET_BY_USER &&
1314                           last_request->intersect)
1315                         return -EOPNOTSUPP;
1316                 /*
1317                  * Process user requests only after previous user/driver/core
1318                  * requests have been processed
1319                  */
1320                 if (last_request->initiator == NL80211_REGDOM_SET_BY_CORE ||
1321                     last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER ||
1322                     last_request->initiator == NL80211_REGDOM_SET_BY_USER) {
1323                         if (regdom_changes(last_request->alpha2))
1324                                 return -EAGAIN;
1325                 }
1326
1327                 if (!regdom_changes(pending_request->alpha2))
1328                         return -EALREADY;
1329
1330                 return 0;
1331         }
1332
1333         return -EINVAL;
1334 }
1335
1336 static void reg_set_request_processed(void)
1337 {
1338         bool need_more_processing = false;
1339
1340         last_request->processed = true;
1341
1342         spin_lock(&reg_requests_lock);
1343         if (!list_empty(&reg_requests_list))
1344                 need_more_processing = true;
1345         spin_unlock(&reg_requests_lock);
1346
1347         if (last_request->initiator == NL80211_REGDOM_SET_BY_USER)
1348                 cancel_delayed_work_sync(&reg_timeout);
1349
1350         if (need_more_processing)
1351                 schedule_work(&reg_work);
1352 }
1353
1354 /**
1355  * __regulatory_hint - hint to the wireless core a regulatory domain
1356  * @wiphy: if the hint comes from country information from an AP, this
1357  *      is required to be set to the wiphy that received the information
1358  * @pending_request: the regulatory request currently being processed
1359  *
1360  * The Wireless subsystem can use this function to hint to the wireless core
1361  * what it believes should be the current regulatory domain.
1362  *
1363  * Returns zero if all went fine, %-EALREADY if a regulatory domain had
1364  * already been set or other standard error codes.
1365  *
1366  * Caller must hold &cfg80211_mutex and &reg_mutex
1367  */
1368 static int __regulatory_hint(struct wiphy *wiphy,
1369                              struct regulatory_request *pending_request)
1370 {
1371         bool intersect = false;
1372         int r = 0;
1373
1374         assert_cfg80211_lock();
1375
1376         r = ignore_request(wiphy, pending_request);
1377
1378         if (r == REG_INTERSECT) {
1379                 if (pending_request->initiator ==
1380                     NL80211_REGDOM_SET_BY_DRIVER) {
1381                         r = reg_copy_regd(&wiphy->regd, cfg80211_regdomain);
1382                         if (r) {
1383                                 kfree(pending_request);
1384                                 return r;
1385                         }
1386                 }
1387                 intersect = true;
1388         } else if (r) {
1389                 /*
1390                  * If the regulatory domain being requested by the
1391                  * driver has already been set just copy it to the
1392                  * wiphy
1393                  */
1394                 if (r == -EALREADY &&
1395                     pending_request->initiator ==
1396                     NL80211_REGDOM_SET_BY_DRIVER) {
1397                         r = reg_copy_regd(&wiphy->regd, cfg80211_regdomain);
1398                         if (r) {
1399                                 kfree(pending_request);
1400                                 return r;
1401                         }
1402                         r = -EALREADY;
1403                         goto new_request;
1404                 }
1405                 kfree(pending_request);
1406                 return r;
1407         }
1408
1409 new_request:
1410         kfree(last_request);
1411
1412         last_request = pending_request;
1413         last_request->intersect = intersect;
1414
1415         pending_request = NULL;
1416
1417         if (last_request->initiator == NL80211_REGDOM_SET_BY_USER) {
1418                 user_alpha2[0] = last_request->alpha2[0];
1419                 user_alpha2[1] = last_request->alpha2[1];
1420         }
1421
1422         /* When r == REG_INTERSECT we do need to call CRDA */
1423         if (r < 0) {
1424                 /*
1425                  * Since CRDA will not be called in this case as we already
1426                  * have applied the requested regulatory domain before we just
1427                  * inform userspace we have processed the request
1428                  */
1429                 if (r == -EALREADY) {
1430                         nl80211_send_reg_change_event(last_request);
1431                         reg_set_request_processed();
1432                 }
1433                 return r;
1434         }
1435
1436         return call_crda(last_request->alpha2);
1437 }
1438
1439 /* This processes *all* regulatory hints */
1440 static void reg_process_hint(struct regulatory_request *reg_request)
1441 {
1442         int r = 0;
1443         struct wiphy *wiphy = NULL;
1444         enum nl80211_reg_initiator initiator = reg_request->initiator;
1445
1446         BUG_ON(!reg_request->alpha2);
1447
1448         if (wiphy_idx_valid(reg_request->wiphy_idx))
1449                 wiphy = wiphy_idx_to_wiphy(reg_request->wiphy_idx);
1450
1451         if (reg_request->initiator == NL80211_REGDOM_SET_BY_DRIVER &&
1452             !wiphy) {
1453                 kfree(reg_request);
1454                 return;
1455         }
1456
1457         r = __regulatory_hint(wiphy, reg_request);
1458         /* This is required so that the orig_* parameters are saved */
1459         if (r == -EALREADY && wiphy &&
1460             wiphy->flags & WIPHY_FLAG_STRICT_REGULATORY) {
1461                 wiphy_update_regulatory(wiphy, initiator);
1462                 return;
1463         }
1464
1465         /*
1466          * We only time out user hints, given that they should be the only
1467          * source of bogus requests.
1468          */
1469         if (r != -EALREADY &&
1470             reg_request->initiator == NL80211_REGDOM_SET_BY_USER)
1471                 schedule_delayed_work(&reg_timeout, msecs_to_jiffies(3142));
1472 }
1473
1474 /*
1475  * Processes regulatory hints, this is all the NL80211_REGDOM_SET_BY_*
1476  * Regulatory hints come on a first come first serve basis and we
1477  * must process each one atomically.
1478  */
1479 static void reg_process_pending_hints(void)
1480 {
1481         struct regulatory_request *reg_request;
1482
1483         mutex_lock(&cfg80211_mutex);
1484         mutex_lock(&reg_mutex);
1485
1486         /* When last_request->processed becomes true this will be rescheduled */
1487         if (last_request && !last_request->processed) {
1488                 REG_DBG_PRINT("Pending regulatory request, waiting "
1489                               "for it to be processed...\n");
1490                 goto out;
1491         }
1492
1493         spin_lock(&reg_requests_lock);
1494
1495         if (list_empty(&reg_requests_list)) {
1496                 spin_unlock(&reg_requests_lock);
1497                 goto out;
1498         }
1499
1500         reg_request = list_first_entry(&reg_requests_list,
1501                                        struct regulatory_request,
1502                                        list);
1503         list_del_init(&reg_request->list);
1504
1505         spin_unlock(&reg_requests_lock);
1506
1507         reg_process_hint(reg_request);
1508
1509 out:
1510         mutex_unlock(&reg_mutex);
1511         mutex_unlock(&cfg80211_mutex);
1512 }
1513
1514 /* Processes beacon hints -- this has nothing to do with country IEs */
1515 static void reg_process_pending_beacon_hints(void)
1516 {
1517         struct cfg80211_registered_device *rdev;
1518         struct reg_beacon *pending_beacon, *tmp;
1519
1520         /*
1521          * No need to hold the reg_mutex here as we just touch wiphys
1522          * and do not read or access regulatory variables.
1523          */
1524         mutex_lock(&cfg80211_mutex);
1525
1526         /* This goes through the _pending_ beacon list */
1527         spin_lock_bh(&reg_pending_beacons_lock);
1528
1529         if (list_empty(&reg_pending_beacons)) {
1530                 spin_unlock_bh(&reg_pending_beacons_lock);
1531                 goto out;
1532         }
1533
1534         list_for_each_entry_safe(pending_beacon, tmp,
1535                                  &reg_pending_beacons, list) {
1536
1537                 list_del_init(&pending_beacon->list);
1538
1539                 /* Applies the beacon hint to current wiphys */
1540                 list_for_each_entry(rdev, &cfg80211_rdev_list, list)
1541                         wiphy_update_new_beacon(&rdev->wiphy, pending_beacon);
1542
1543                 /* Remembers the beacon hint for new wiphys or reg changes */
1544                 list_add_tail(&pending_beacon->list, &reg_beacon_list);
1545         }
1546
1547         spin_unlock_bh(&reg_pending_beacons_lock);
1548 out:
1549         mutex_unlock(&cfg80211_mutex);
1550 }
1551
1552 static void reg_todo(struct work_struct *work)
1553 {
1554         reg_process_pending_hints();
1555         reg_process_pending_beacon_hints();
1556 }
1557
1558 static void queue_regulatory_request(struct regulatory_request *request)
1559 {
1560         if (isalpha(request->alpha2[0]))
1561                 request->alpha2[0] = toupper(request->alpha2[0]);
1562         if (isalpha(request->alpha2[1]))
1563                 request->alpha2[1] = toupper(request->alpha2[1]);
1564
1565         spin_lock(&reg_requests_lock);
1566         list_add_tail(&request->list, &reg_requests_list);
1567         spin_unlock(&reg_requests_lock);
1568
1569         schedule_work(&reg_work);
1570 }
1571
1572 /*
1573  * Core regulatory hint -- happens during cfg80211_init()
1574  * and when we restore regulatory settings.
1575  */
1576 static int regulatory_hint_core(const char *alpha2)
1577 {
1578         struct regulatory_request *request;
1579
1580         kfree(last_request);
1581         last_request = NULL;
1582
1583         request = kzalloc(sizeof(struct regulatory_request),
1584                           GFP_KERNEL);
1585         if (!request)
1586                 return -ENOMEM;
1587
1588         request->alpha2[0] = alpha2[0];
1589         request->alpha2[1] = alpha2[1];
1590         request->initiator = NL80211_REGDOM_SET_BY_CORE;
1591
1592         queue_regulatory_request(request);
1593
1594         return 0;
1595 }
1596
1597 /* User hints */
1598 int regulatory_hint_user(const char *alpha2)
1599 {
1600         struct regulatory_request *request;
1601
1602         BUG_ON(!alpha2);
1603
1604         request = kzalloc(sizeof(struct regulatory_request), GFP_KERNEL);
1605         if (!request)
1606                 return -ENOMEM;
1607
1608         request->wiphy_idx = WIPHY_IDX_STALE;
1609         request->alpha2[0] = alpha2[0];
1610         request->alpha2[1] = alpha2[1];
1611         request->initiator = NL80211_REGDOM_SET_BY_USER;
1612
1613         queue_regulatory_request(request);
1614
1615         return 0;
1616 }
1617
1618 /* Driver hints */
1619 int regulatory_hint(struct wiphy *wiphy, const char *alpha2)
1620 {
1621         struct regulatory_request *request;
1622
1623         BUG_ON(!alpha2);
1624         BUG_ON(!wiphy);
1625
1626         request = kzalloc(sizeof(struct regulatory_request), GFP_KERNEL);
1627         if (!request)
1628                 return -ENOMEM;
1629
1630         request->wiphy_idx = get_wiphy_idx(wiphy);
1631
1632         /* Must have registered wiphy first */
1633         BUG_ON(!wiphy_idx_valid(request->wiphy_idx));
1634
1635         request->alpha2[0] = alpha2[0];
1636         request->alpha2[1] = alpha2[1];
1637         request->initiator = NL80211_REGDOM_SET_BY_DRIVER;
1638
1639         queue_regulatory_request(request);
1640
1641         return 0;
1642 }
1643 EXPORT_SYMBOL(regulatory_hint);
1644
1645 /*
1646  * We hold wdev_lock() here so we cannot hold cfg80211_mutex() and
1647  * therefore cannot iterate over the rdev list here.
1648  */
1649 void regulatory_hint_11d(struct wiphy *wiphy,
1650                          enum ieee80211_band band,
1651                          u8 *country_ie,
1652                          u8 country_ie_len)
1653 {
1654         char alpha2[2];
1655         enum environment_cap env = ENVIRON_ANY;
1656         struct regulatory_request *request;
1657
1658         mutex_lock(&reg_mutex);
1659
1660         if (unlikely(!last_request))
1661                 goto out;
1662
1663         /* IE len must be evenly divisible by 2 */
1664         if (country_ie_len & 0x01)
1665                 goto out;
1666
1667         if (country_ie_len < IEEE80211_COUNTRY_IE_MIN_LEN)
1668                 goto out;
1669
1670         alpha2[0] = country_ie[0];
1671         alpha2[1] = country_ie[1];
1672
1673         if (country_ie[2] == 'I')
1674                 env = ENVIRON_INDOOR;
1675         else if (country_ie[2] == 'O')
1676                 env = ENVIRON_OUTDOOR;
1677
1678         /*
1679          * We will run this only upon a successful connection on cfg80211.
1680          * We leave conflict resolution to the workqueue, where can hold
1681          * cfg80211_mutex.
1682          */
1683         if (likely(last_request->initiator ==
1684             NL80211_REGDOM_SET_BY_COUNTRY_IE &&
1685             wiphy_idx_valid(last_request->wiphy_idx)))
1686                 goto out;
1687
1688         request = kzalloc(sizeof(struct regulatory_request), GFP_KERNEL);
1689         if (!request)
1690                 goto out;
1691
1692         request->wiphy_idx = get_wiphy_idx(wiphy);
1693         request->alpha2[0] = alpha2[0];
1694         request->alpha2[1] = alpha2[1];
1695         request->initiator = NL80211_REGDOM_SET_BY_COUNTRY_IE;
1696         request->country_ie_env = env;
1697
1698         mutex_unlock(&reg_mutex);
1699
1700         queue_regulatory_request(request);
1701
1702         return;
1703
1704 out:
1705         mutex_unlock(&reg_mutex);
1706 }
1707
1708 static void restore_alpha2(char *alpha2, bool reset_user)
1709 {
1710         /* indicates there is no alpha2 to consider for restoration */
1711         alpha2[0] = '9';
1712         alpha2[1] = '7';
1713
1714         /* The user setting has precedence over the module parameter */
1715         if (is_user_regdom_saved()) {
1716                 /* Unless we're asked to ignore it and reset it */
1717                 if (reset_user) {
1718                         REG_DBG_PRINT("Restoring regulatory settings "
1719                                "including user preference\n");
1720                         user_alpha2[0] = '9';
1721                         user_alpha2[1] = '7';
1722
1723                         /*
1724                          * If we're ignoring user settings, we still need to
1725                          * check the module parameter to ensure we put things
1726                          * back as they were for a full restore.
1727                          */
1728                         if (!is_world_regdom(ieee80211_regdom)) {
1729                                 REG_DBG_PRINT("Keeping preference on "
1730                                        "module parameter ieee80211_regdom: %c%c\n",
1731                                        ieee80211_regdom[0],
1732                                        ieee80211_regdom[1]);
1733                                 alpha2[0] = ieee80211_regdom[0];
1734                                 alpha2[1] = ieee80211_regdom[1];
1735                         }
1736                 } else {
1737                         REG_DBG_PRINT("Restoring regulatory settings "
1738                                "while preserving user preference for: %c%c\n",
1739                                user_alpha2[0],
1740                                user_alpha2[1]);
1741                         alpha2[0] = user_alpha2[0];
1742                         alpha2[1] = user_alpha2[1];
1743                 }
1744         } else if (!is_world_regdom(ieee80211_regdom)) {
1745                 REG_DBG_PRINT("Keeping preference on "
1746                        "module parameter ieee80211_regdom: %c%c\n",
1747                        ieee80211_regdom[0],
1748                        ieee80211_regdom[1]);
1749                 alpha2[0] = ieee80211_regdom[0];
1750                 alpha2[1] = ieee80211_regdom[1];
1751         } else
1752                 REG_DBG_PRINT("Restoring regulatory settings\n");
1753 }
1754
1755 /*
1756  * Restoring regulatory settings involves ingoring any
1757  * possibly stale country IE information and user regulatory
1758  * settings if so desired, this includes any beacon hints
1759  * learned as we could have traveled outside to another country
1760  * after disconnection. To restore regulatory settings we do
1761  * exactly what we did at bootup:
1762  *
1763  *   - send a core regulatory hint
1764  *   - send a user regulatory hint if applicable
1765  *
1766  * Device drivers that send a regulatory hint for a specific country
1767  * keep their own regulatory domain on wiphy->regd so that does does
1768  * not need to be remembered.
1769  */
1770 static void restore_regulatory_settings(bool reset_user)
1771 {
1772         char alpha2[2];
1773         struct reg_beacon *reg_beacon, *btmp;
1774         struct regulatory_request *reg_request, *tmp;
1775         LIST_HEAD(tmp_reg_req_list);
1776
1777         mutex_lock(&cfg80211_mutex);
1778         mutex_lock(&reg_mutex);
1779
1780         reset_regdomains();
1781         restore_alpha2(alpha2, reset_user);
1782
1783         /*
1784          * If there's any pending requests we simply
1785          * stash them to a temporary pending queue and
1786          * add then after we've restored regulatory
1787          * settings.
1788          */
1789         spin_lock(&reg_requests_lock);
1790         if (!list_empty(&reg_requests_list)) {
1791                 list_for_each_entry_safe(reg_request, tmp,
1792                                          &reg_requests_list, list) {
1793                         if (reg_request->initiator !=
1794                             NL80211_REGDOM_SET_BY_USER)
1795                                 continue;
1796                         list_del(&reg_request->list);
1797                         list_add_tail(&reg_request->list, &tmp_reg_req_list);
1798                 }
1799         }
1800         spin_unlock(&reg_requests_lock);
1801
1802         /* Clear beacon hints */
1803         spin_lock_bh(&reg_pending_beacons_lock);
1804         if (!list_empty(&reg_pending_beacons)) {
1805                 list_for_each_entry_safe(reg_beacon, btmp,
1806                                          &reg_pending_beacons, list) {
1807                         list_del(&reg_beacon->list);
1808                         kfree(reg_beacon);
1809                 }
1810         }
1811         spin_unlock_bh(&reg_pending_beacons_lock);
1812
1813         if (!list_empty(&reg_beacon_list)) {
1814                 list_for_each_entry_safe(reg_beacon, btmp,
1815                                          &reg_beacon_list, list) {
1816                         list_del(&reg_beacon->list);
1817                         kfree(reg_beacon);
1818                 }
1819         }
1820
1821         /* First restore to the basic regulatory settings */
1822         cfg80211_regdomain = cfg80211_world_regdom;
1823
1824         mutex_unlock(&reg_mutex);
1825         mutex_unlock(&cfg80211_mutex);
1826
1827         regulatory_hint_core(cfg80211_regdomain->alpha2);
1828
1829         /*
1830          * This restores the ieee80211_regdom module parameter
1831          * preference or the last user requested regulatory
1832          * settings, user regulatory settings takes precedence.
1833          */
1834         if (is_an_alpha2(alpha2))
1835                 regulatory_hint_user(user_alpha2);
1836
1837         if (list_empty(&tmp_reg_req_list))
1838                 return;
1839
1840         mutex_lock(&cfg80211_mutex);
1841         mutex_lock(&reg_mutex);
1842
1843         spin_lock(&reg_requests_lock);
1844         list_for_each_entry_safe(reg_request, tmp, &tmp_reg_req_list, list) {
1845                 REG_DBG_PRINT("Adding request for country %c%c back "
1846                               "into the queue\n",
1847                               reg_request->alpha2[0],
1848                               reg_request->alpha2[1]);
1849                 list_del(&reg_request->list);
1850                 list_add_tail(&reg_request->list, &reg_requests_list);
1851         }
1852         spin_unlock(&reg_requests_lock);
1853
1854         mutex_unlock(&reg_mutex);
1855         mutex_unlock(&cfg80211_mutex);
1856
1857         REG_DBG_PRINT("Kicking the queue\n");
1858
1859         schedule_work(&reg_work);
1860 }
1861
1862 void regulatory_hint_disconnect(void)
1863 {
1864         REG_DBG_PRINT("All devices are disconnected, going to "
1865                       "restore regulatory settings\n");
1866         restore_regulatory_settings(false);
1867 }
1868
1869 static bool freq_is_chan_12_13_14(u16 freq)
1870 {
1871         if (freq == ieee80211_channel_to_frequency(12, IEEE80211_BAND_2GHZ) ||
1872             freq == ieee80211_channel_to_frequency(13, IEEE80211_BAND_2GHZ) ||
1873             freq == ieee80211_channel_to_frequency(14, IEEE80211_BAND_2GHZ))
1874                 return true;
1875         return false;
1876 }
1877
1878 int regulatory_hint_found_beacon(struct wiphy *wiphy,
1879                                  struct ieee80211_channel *beacon_chan,
1880                                  gfp_t gfp)
1881 {
1882         struct reg_beacon *reg_beacon;
1883
1884         if (likely((beacon_chan->beacon_found ||
1885             (beacon_chan->flags & IEEE80211_CHAN_RADAR) ||
1886             (beacon_chan->band == IEEE80211_BAND_2GHZ &&
1887              !freq_is_chan_12_13_14(beacon_chan->center_freq)))))
1888                 return 0;
1889
1890         reg_beacon = kzalloc(sizeof(struct reg_beacon), gfp);
1891         if (!reg_beacon)
1892                 return -ENOMEM;
1893
1894         REG_DBG_PRINT("Found new beacon on "
1895                       "frequency: %d MHz (Ch %d) on %s\n",
1896                       beacon_chan->center_freq,
1897                       ieee80211_frequency_to_channel(beacon_chan->center_freq),
1898                       wiphy_name(wiphy));
1899
1900         memcpy(&reg_beacon->chan, beacon_chan,
1901                 sizeof(struct ieee80211_channel));
1902
1903
1904         /*
1905          * Since we can be called from BH or and non-BH context
1906          * we must use spin_lock_bh()
1907          */
1908         spin_lock_bh(&reg_pending_beacons_lock);
1909         list_add_tail(&reg_beacon->list, &reg_pending_beacons);
1910         spin_unlock_bh(&reg_pending_beacons_lock);
1911
1912         schedule_work(&reg_work);
1913
1914         return 0;
1915 }
1916
1917 static void print_rd_rules(const struct ieee80211_regdomain *rd)
1918 {
1919         unsigned int i;
1920         const struct ieee80211_reg_rule *reg_rule = NULL;
1921         const struct ieee80211_freq_range *freq_range = NULL;
1922         const struct ieee80211_power_rule *power_rule = NULL;
1923
1924         pr_info("    (start_freq - end_freq @ bandwidth), (max_antenna_gain, max_eirp)\n");
1925
1926         for (i = 0; i < rd->n_reg_rules; i++) {
1927                 reg_rule = &rd->reg_rules[i];
1928                 freq_range = &reg_rule->freq_range;
1929                 power_rule = &reg_rule->power_rule;
1930
1931                 /*
1932                  * There may not be documentation for max antenna gain
1933                  * in certain regions
1934                  */
1935                 if (power_rule->max_antenna_gain)
1936                         pr_info("    (%d KHz - %d KHz @ %d KHz), (%d mBi, %d mBm)\n",
1937                                 freq_range->start_freq_khz,
1938                                 freq_range->end_freq_khz,
1939                                 freq_range->max_bandwidth_khz,
1940                                 power_rule->max_antenna_gain,
1941                                 power_rule->max_eirp);
1942                 else
1943                         pr_info("    (%d KHz - %d KHz @ %d KHz), (N/A, %d mBm)\n",
1944                                 freq_range->start_freq_khz,
1945                                 freq_range->end_freq_khz,
1946                                 freq_range->max_bandwidth_khz,
1947                                 power_rule->max_eirp);
1948         }
1949 }
1950
1951 static void print_regdomain(const struct ieee80211_regdomain *rd)
1952 {
1953
1954         if (is_intersected_alpha2(rd->alpha2)) {
1955
1956                 if (last_request->initiator ==
1957                     NL80211_REGDOM_SET_BY_COUNTRY_IE) {
1958                         struct cfg80211_registered_device *rdev;
1959                         rdev = cfg80211_rdev_by_wiphy_idx(
1960                                 last_request->wiphy_idx);
1961                         if (rdev) {
1962                                 pr_info("Current regulatory domain updated by AP to: %c%c\n",
1963                                         rdev->country_ie_alpha2[0],
1964                                         rdev->country_ie_alpha2[1]);
1965                         } else
1966                                 pr_info("Current regulatory domain intersected:\n");
1967                 } else
1968                         pr_info("Current regulatory domain intersected:\n");
1969         } else if (is_world_regdom(rd->alpha2))
1970                 pr_info("World regulatory domain updated:\n");
1971         else {
1972                 if (is_unknown_alpha2(rd->alpha2))
1973                         pr_info("Regulatory domain changed to driver built-in settings (unknown country)\n");
1974                 else
1975                         pr_info("Regulatory domain changed to country: %c%c\n",
1976                                 rd->alpha2[0], rd->alpha2[1]);
1977         }
1978         print_rd_rules(rd);
1979 }
1980
1981 static void print_regdomain_info(const struct ieee80211_regdomain *rd)
1982 {
1983         pr_info("Regulatory domain: %c%c\n", rd->alpha2[0], rd->alpha2[1]);
1984         print_rd_rules(rd);
1985 }
1986
1987 /* Takes ownership of rd only if it doesn't fail */
1988 static int __set_regdom(const struct ieee80211_regdomain *rd)
1989 {
1990         const struct ieee80211_regdomain *intersected_rd = NULL;
1991         struct cfg80211_registered_device *rdev = NULL;
1992         struct wiphy *request_wiphy;
1993         /* Some basic sanity checks first */
1994
1995         if (is_world_regdom(rd->alpha2)) {
1996                 if (WARN_ON(!reg_is_valid_request(rd->alpha2)))
1997                         return -EINVAL;
1998                 update_world_regdomain(rd);
1999                 return 0;
2000         }
2001
2002         if (!is_alpha2_set(rd->alpha2) && !is_an_alpha2(rd->alpha2) &&
2003                         !is_unknown_alpha2(rd->alpha2))
2004                 return -EINVAL;
2005
2006         if (!last_request)
2007                 return -EINVAL;
2008
2009         /*
2010          * Lets only bother proceeding on the same alpha2 if the current
2011          * rd is non static (it means CRDA was present and was used last)
2012          * and the pending request came in from a country IE
2013          */
2014         if (last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE) {
2015                 /*
2016                  * If someone else asked us to change the rd lets only bother
2017                  * checking if the alpha2 changes if CRDA was already called
2018                  */
2019                 if (!regdom_changes(rd->alpha2))
2020                         return -EINVAL;
2021         }
2022
2023         /*
2024          * Now lets set the regulatory domain, update all driver channels
2025          * and finally inform them of what we have done, in case they want
2026          * to review or adjust their own settings based on their own
2027          * internal EEPROM data
2028          */
2029
2030         if (WARN_ON(!reg_is_valid_request(rd->alpha2)))
2031                 return -EINVAL;
2032
2033         if (!is_valid_rd(rd)) {
2034                 pr_err("Invalid regulatory domain detected:\n");
2035                 print_regdomain_info(rd);
2036                 return -EINVAL;
2037         }
2038
2039         request_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);
2040
2041         if (!last_request->intersect) {
2042                 int r;
2043
2044                 if (last_request->initiator != NL80211_REGDOM_SET_BY_DRIVER) {
2045                         reset_regdomains();
2046                         cfg80211_regdomain = rd;
2047                         return 0;
2048                 }
2049
2050                 /*
2051                  * For a driver hint, lets copy the regulatory domain the
2052                  * driver wanted to the wiphy to deal with conflicts
2053                  */
2054
2055                 /*
2056                  * Userspace could have sent two replies with only
2057                  * one kernel request.
2058                  */
2059                 if (request_wiphy->regd)
2060                         return -EALREADY;
2061
2062                 r = reg_copy_regd(&request_wiphy->regd, rd);
2063                 if (r)
2064                         return r;
2065
2066                 reset_regdomains();
2067                 cfg80211_regdomain = rd;
2068                 return 0;
2069         }
2070
2071         /* Intersection requires a bit more work */
2072
2073         if (last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE) {
2074
2075                 intersected_rd = regdom_intersect(rd, cfg80211_regdomain);
2076                 if (!intersected_rd)
2077                         return -EINVAL;
2078
2079                 /*
2080                  * We can trash what CRDA provided now.
2081                  * However if a driver requested this specific regulatory
2082                  * domain we keep it for its private use
2083                  */
2084                 if (last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER)
2085                         request_wiphy->regd = rd;
2086                 else
2087                         kfree(rd);
2088
2089                 rd = NULL;
2090
2091                 reset_regdomains();
2092                 cfg80211_regdomain = intersected_rd;
2093
2094                 return 0;
2095         }
2096
2097         if (!intersected_rd)
2098                 return -EINVAL;
2099
2100         rdev = wiphy_to_dev(request_wiphy);
2101
2102         rdev->country_ie_alpha2[0] = rd->alpha2[0];
2103         rdev->country_ie_alpha2[1] = rd->alpha2[1];
2104         rdev->env = last_request->country_ie_env;
2105
2106         BUG_ON(intersected_rd == rd);
2107
2108         kfree(rd);
2109         rd = NULL;
2110
2111         reset_regdomains();
2112         cfg80211_regdomain = intersected_rd;
2113
2114         return 0;
2115 }
2116
2117
2118 /*
2119  * Use this call to set the current regulatory domain. Conflicts with
2120  * multiple drivers can be ironed out later. Caller must've already
2121  * kmalloc'd the rd structure. Caller must hold cfg80211_mutex
2122  */
2123 int set_regdom(const struct ieee80211_regdomain *rd)
2124 {
2125         int r;
2126
2127         assert_cfg80211_lock();
2128
2129         mutex_lock(&reg_mutex);
2130
2131         /* Note that this doesn't update the wiphys, this is done below */
2132         r = __set_regdom(rd);
2133         if (r) {
2134                 kfree(rd);
2135                 mutex_unlock(&reg_mutex);
2136                 return r;
2137         }
2138
2139         /* This would make this whole thing pointless */
2140         if (!last_request->intersect)
2141                 BUG_ON(rd != cfg80211_regdomain);
2142
2143         /* update all wiphys now with the new established regulatory domain */
2144         update_all_wiphy_regulatory(last_request->initiator);
2145
2146         print_regdomain(cfg80211_regdomain);
2147
2148         nl80211_send_reg_change_event(last_request);
2149
2150         reg_set_request_processed();
2151
2152         mutex_unlock(&reg_mutex);
2153
2154         return r;
2155 }
2156
2157 #ifdef CONFIG_HOTPLUG
2158 int reg_device_uevent(struct device *dev, struct kobj_uevent_env *env)
2159 {
2160         if (last_request && !last_request->processed) {
2161                 if (add_uevent_var(env, "COUNTRY=%c%c",
2162                                    last_request->alpha2[0],
2163                                    last_request->alpha2[1]))
2164                         return -ENOMEM;
2165         }
2166
2167         return 0;
2168 }
2169 #else
2170 int reg_device_uevent(struct device *dev, struct kobj_uevent_env *env)
2171 {
2172         return -ENODEV;
2173 }
2174 #endif /* CONFIG_HOTPLUG */
2175
2176 /* Caller must hold cfg80211_mutex */
2177 void reg_device_remove(struct wiphy *wiphy)
2178 {
2179         struct wiphy *request_wiphy = NULL;
2180
2181         assert_cfg80211_lock();
2182
2183         mutex_lock(&reg_mutex);
2184
2185         kfree(wiphy->regd);
2186
2187         if (last_request)
2188                 request_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);
2189
2190         if (!request_wiphy || request_wiphy != wiphy)
2191                 goto out;
2192
2193         last_request->wiphy_idx = WIPHY_IDX_STALE;
2194         last_request->country_ie_env = ENVIRON_ANY;
2195 out:
2196         mutex_unlock(&reg_mutex);
2197 }
2198
2199 static void reg_timeout_work(struct work_struct *work)
2200 {
2201         REG_DBG_PRINT("Timeout while waiting for CRDA to reply, "
2202                       "restoring regulatory settings\n");
2203         restore_regulatory_settings(true);
2204 }
2205
2206 int __init regulatory_init(void)
2207 {
2208         int err = 0;
2209
2210         reg_pdev = platform_device_register_simple("regulatory", 0, NULL, 0);
2211         if (IS_ERR(reg_pdev))
2212                 return PTR_ERR(reg_pdev);
2213
2214         reg_pdev->dev.type = &reg_device_type;
2215
2216         spin_lock_init(&reg_requests_lock);
2217         spin_lock_init(&reg_pending_beacons_lock);
2218
2219         cfg80211_regdomain = cfg80211_world_regdom;
2220
2221         user_alpha2[0] = '9';
2222         user_alpha2[1] = '7';
2223
2224         /* We always try to get an update for the static regdomain */
2225         err = regulatory_hint_core(cfg80211_regdomain->alpha2);
2226         if (err) {
2227                 if (err == -ENOMEM)
2228                         return err;
2229                 /*
2230                  * N.B. kobject_uevent_env() can fail mainly for when we're out
2231                  * memory which is handled and propagated appropriately above
2232                  * but it can also fail during a netlink_broadcast() or during
2233                  * early boot for call_usermodehelper(). For now treat these
2234                  * errors as non-fatal.
2235                  */
2236                 pr_err("kobject_uevent_env() was unable to call CRDA during init\n");
2237 #ifdef CONFIG_CFG80211_REG_DEBUG
2238                 /* We want to find out exactly why when debugging */
2239                 WARN_ON(err);
2240 #endif
2241         }
2242
2243         /*
2244          * Finally, if the user set the module parameter treat it
2245          * as a user hint.
2246          */
2247         if (!is_world_regdom(ieee80211_regdom))
2248                 regulatory_hint_user(ieee80211_regdom);
2249
2250         return 0;
2251 }
2252
2253 void /* __init_or_exit */ regulatory_exit(void)
2254 {
2255         struct regulatory_request *reg_request, *tmp;
2256         struct reg_beacon *reg_beacon, *btmp;
2257
2258         cancel_work_sync(&reg_work);
2259         cancel_delayed_work_sync(&reg_timeout);
2260
2261         mutex_lock(&cfg80211_mutex);
2262         mutex_lock(&reg_mutex);
2263
2264         reset_regdomains();
2265
2266         kfree(last_request);
2267
2268         platform_device_unregister(reg_pdev);
2269
2270         spin_lock_bh(&reg_pending_beacons_lock);
2271         if (!list_empty(&reg_pending_beacons)) {
2272                 list_for_each_entry_safe(reg_beacon, btmp,
2273                                          &reg_pending_beacons, list) {
2274                         list_del(&reg_beacon->list);
2275                         kfree(reg_beacon);
2276                 }
2277         }
2278         spin_unlock_bh(&reg_pending_beacons_lock);
2279
2280         if (!list_empty(&reg_beacon_list)) {
2281                 list_for_each_entry_safe(reg_beacon, btmp,
2282                                          &reg_beacon_list, list) {
2283                         list_del(&reg_beacon->list);
2284                         kfree(reg_beacon);
2285                 }
2286         }
2287
2288         spin_lock(&reg_requests_lock);
2289         if (!list_empty(&reg_requests_list)) {
2290                 list_for_each_entry_safe(reg_request, tmp,
2291                                          &reg_requests_list, list) {
2292                         list_del(&reg_request->list);
2293                         kfree(reg_request);
2294                 }
2295         }
2296         spin_unlock(&reg_requests_lock);
2297
2298         mutex_unlock(&reg_mutex);
2299         mutex_unlock(&cfg80211_mutex);
2300 }