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/random.h>
  52 #include <linux/ctype.h>
  53 #include <linux/nl80211.h>
  54 #include <linux/platform_device.h>
  55 #include <linux/moduleparam.h>
  56 #include <net/cfg80211.h>
  57 #include "core.h"
  58 #include "reg.h"
  59 #include "regdb.h"
  60 #include "nl80211.h"
  61
  62 #ifdef CONFIG_CFG80211_REG_DEBUG
  63 #define REG_DBG_PRINT(format, args...)                  \
  64         printk(KERN_DEBUG pr_fmt(format), ##args)
  65 #else
  66 #define REG_DBG_PRINT(args...)
  67 #endif
  68
  69 static struct regulatory_request core_request_world = {
  70         .initiator = NL80211_REGDOM_SET_BY_CORE,
  71         .alpha2[0] = '0',
  72         .alpha2[1] = '0',
  73         .intersect = false,
  74         .processed = true,
  75         .country_ie_env = ENVIRON_ANY,
  76 };
  77
  78 /* Receipt of information from last regulatory request */
  79 static struct regulatory_request *last_request = &core_request_world;
  80
  81 /* To trigger userspace events */
  82 static struct platform_device *reg_pdev;
  83
  84 static struct device_type reg_device_type = {
  85         .uevent = reg_device_uevent,
  86 };
  87
  88 /*
  89  * Central wireless core regulatory domains, we only need two,
  90  * the current one and a world regulatory domain in case we have no
  91  * information to give us an alpha2
  92  */
  93 const struct ieee80211_regdomain *cfg80211_regdomain;
  94
  95 /*
  96  * Protects static reg.c components:
  97  *     - cfg80211_world_regdom
  98  *     - cfg80211_regdom
  99  *     - last_request
 100  *     - reg_num_devs_support_basehint
 101  */
 102 static DEFINE_MUTEX(reg_mutex);
 103
 104 /*
 105  * Number of devices that registered to the core
 106  * that support cellular base station regulatory hints
 107  */
 108 static int reg_num_devs_support_basehint;
 109
 110 static inline void assert_reg_lock(void)
 111 {
 112         lockdep_assert_held(&reg_mutex);
 113 }
 114
 115 /* Used to queue up regulatory hints */
 116 static LIST_HEAD(reg_requests_list);
 117 static spinlock_t reg_requests_lock;
 118
 119 /* Used to queue up beacon hints for review */
 120 static LIST_HEAD(reg_pending_beacons);
 121 static spinlock_t reg_pending_beacons_lock;
 122
 123 /* Used to keep track of processed beacon hints */
 124 static LIST_HEAD(reg_beacon_list);
 125
 126 struct reg_beacon {
 127         struct list_head list;
 128         struct ieee80211_channel chan;
 129 };
 130
 131 static void reg_todo(struct work_struct *work);
 132 static DECLARE_WORK(reg_work, reg_todo);
 133
 134 static void reg_timeout_work(struct work_struct *work);
 135 static DECLARE_DELAYED_WORK(reg_timeout, reg_timeout_work);
 136
 137 /* We keep a static world regulatory domain in case of the absence of CRDA */
 138 static const struct ieee80211_regdomain world_regdom = {
 139         .n_reg_rules = 6,
 140         .alpha2 =  "00",
 141         .reg_rules = {
 142                 /* IEEE 802.11b/g, channels 1..11 */
 143                 REG_RULE(2412-10, 2462+10, 40, 6, 20, 0),
 144                 /* IEEE 802.11b/g, channels 12..13. No HT40
 145                  * channel fits here. */
 146                 REG_RULE(2467-10, 2472+10, 20, 6, 20,
 147                         NL80211_RRF_PASSIVE_SCAN |
 148                         NL80211_RRF_NO_IBSS),
 149                 /* IEEE 802.11 channel 14 - Only JP enables
 150                  * this and for 802.11b only */
 151                 REG_RULE(2484-10, 2484+10, 20, 6, 20,
 152                         NL80211_RRF_PASSIVE_SCAN |
 153                         NL80211_RRF_NO_IBSS |
 154                         NL80211_RRF_NO_OFDM),
 155                 /* IEEE 802.11a, channel 36..48 */
 156                 REG_RULE(5180-10, 5240+10, 40, 6, 20,
 157                         NL80211_RRF_PASSIVE_SCAN |
 158                         NL80211_RRF_NO_IBSS),
 159
 160                 /* NB: 5260 MHz - 5700 MHz requies DFS */
 161
 162                 /* IEEE 802.11a, channel 149..165 */
 163                 REG_RULE(5745-10, 5825+10, 40, 6, 20,
 164                         NL80211_RRF_PASSIVE_SCAN |
 165                         NL80211_RRF_NO_IBSS),
 166
 167                 /* IEEE 802.11ad (60gHz), channels 1..3 */
 168                 REG_RULE(56160+2160*1-1080, 56160+2160*3+1080, 2160, 0, 0, 0),
 169         }
 170 };
 171
 172 static const struct ieee80211_regdomain *cfg80211_world_regdom =
 173         &world_regdom;
 174
 175 static char *ieee80211_regdom = "00";
 176 static char user_alpha2[2];
 177
 178 module_param(ieee80211_regdom, charp, 0444);
 179 MODULE_PARM_DESC(ieee80211_regdom, "IEEE 802.11 regulatory domain code");
 180
 181 static void reset_regdomains(bool full_reset)
 182 {
 183         /* avoid freeing static information or freeing something twice */
 184         if (cfg80211_regdomain == cfg80211_world_regdom)
 185                 cfg80211_regdomain = NULL;
 186         if (cfg80211_world_regdom == &world_regdom)
 187                 cfg80211_world_regdom = NULL;
 188         if (cfg80211_regdomain == &world_regdom)
 189                 cfg80211_regdomain = NULL;
 190
 191         kfree(cfg80211_regdomain);
 192         kfree(cfg80211_world_regdom);
 193
 194         cfg80211_world_regdom = &world_regdom;
 195         cfg80211_regdomain = NULL;
 196
 197         if (!full_reset)
 198                 return;
 199
 200         if (last_request != &core_request_world)
 201                 kfree(last_request);
 202         last_request = &core_request_world;
 203 }
 204
 205 /*
 206  * Dynamic world regulatory domain requested by the wireless
 207  * core upon initialization
 208  */
 209 static void update_world_regdomain(const struct ieee80211_regdomain *rd)
 210 {
 211         BUG_ON(!last_request);
 212
 213         reset_regdomains(false);
 214
 215         cfg80211_world_regdom = rd;
 216         cfg80211_regdomain = rd;
 217 }
 218
 219 bool is_world_regdom(const char *alpha2)
 220 {
 221         if (!alpha2)
 222                 return false;
 223         if (alpha2[0] == '0' && alpha2[1] == '0')
 224                 return true;
 225         return false;
 226 }
 227
 228 static bool is_alpha2_set(const char *alpha2)
 229 {
 230         if (!alpha2)
 231                 return false;
 232         if (alpha2[0] != 0 && alpha2[1] != 0)
 233                 return true;
 234         return false;
 235 }
 236
 237 static bool is_unknown_alpha2(const char *alpha2)
 238 {
 239         if (!alpha2)
 240                 return false;
 241         /*
 242          * Special case where regulatory domain was built by driver
 243          * but a specific alpha2 cannot be determined
 244          */
 245         if (alpha2[0] == '9' && alpha2[1] == '9')
 246                 return true;
 247         return false;
 248 }
 249
 250 static bool is_intersected_alpha2(const char *alpha2)
 251 {
 252         if (!alpha2)
 253                 return false;
 254         /*
 255          * Special case where regulatory domain is the
 256          * result of an intersection between two regulatory domain
 257          * structures
 258          */
 259         if (alpha2[0] == '9' && alpha2[1] == '8')
 260                 return true;
 261         return false;
 262 }
 263
 264 static bool is_an_alpha2(const char *alpha2)
 265 {
 266         if (!alpha2)
 267                 return false;
 268         if (isalpha(alpha2[0]) && isalpha(alpha2[1]))
 269                 return true;
 270         return false;
 271 }
 272
 273 static bool alpha2_equal(const char *alpha2_x, const char *alpha2_y)
 274 {
 275         if (!alpha2_x || !alpha2_y)
 276                 return false;
 277         if (alpha2_x[0] == alpha2_y[0] &&
 278                 alpha2_x[1] == alpha2_y[1])
 279                 return true;
 280         return false;
 281 }
 282
 283 static bool regdom_changes(const char *alpha2)
 284 {
 285         assert_cfg80211_lock();
 286
 287         if (!cfg80211_regdomain)
 288                 return true;
 289         if (alpha2_equal(cfg80211_regdomain->alpha2, alpha2))
 290                 return false;
 291         return true;
 292 }
 293
 294 /*
 295  * The NL80211_REGDOM_SET_BY_USER regdom alpha2 is cached, this lets
 296  * you know if a valid regulatory hint with NL80211_REGDOM_SET_BY_USER
 297  * has ever been issued.
 298  */
 299 static bool is_user_regdom_saved(void)
 300 {
 301         if (user_alpha2[0] == '9' && user_alpha2[1] == '7')
 302                 return false;
 303
 304         /* This would indicate a mistake on the design */
 305         if (WARN((!is_world_regdom(user_alpha2) &&
 306                   !is_an_alpha2(user_alpha2)),
 307                  "Unexpected user alpha2: %c%c\n",
 308                  user_alpha2[0],
 309                  user_alpha2[1]))
 310                 return false;
 311
 312         return true;
 313 }
 314
 315 static int reg_copy_regd(const struct ieee80211_regdomain **dst_regd,
 316                          const struct ieee80211_regdomain *src_regd)
 317 {
 318         struct ieee80211_regdomain *regd;
 319         int size_of_regd = 0;
 320         unsigned int i;
 321
 322         size_of_regd = sizeof(struct ieee80211_regdomain) +
 323           ((src_regd->n_reg_rules + 1) * sizeof(struct ieee80211_reg_rule));
 324
 325         regd = kzalloc(size_of_regd, GFP_KERNEL);
 326         if (!regd)
 327                 return -ENOMEM;
 328
 329         memcpy(regd, src_regd, sizeof(struct ieee80211_regdomain));
 330
 331         for (i = 0; i < src_regd->n_reg_rules; i++)
 332                 memcpy(&regd->reg_rules[i], &src_regd->reg_rules[i],
 333                         sizeof(struct ieee80211_reg_rule));
 334
 335         *dst_regd = regd;
 336         return 0;
 337 }
 338
 339 #ifdef CONFIG_CFG80211_INTERNAL_REGDB
 340 struct reg_regdb_search_request {
 341         char alpha2[2];
 342         struct list_head list;
 343 };
 344
 345 static LIST_HEAD(reg_regdb_search_list);
 346 static DEFINE_MUTEX(reg_regdb_search_mutex);
 347
 348 static void reg_regdb_search(struct work_struct *work)
 349 {
 350         struct reg_regdb_search_request *request;
 351         const struct ieee80211_regdomain *curdom, *regdom;
 352         int i, r;
 353         bool set_reg = false;
 354
 355         mutex_lock(&cfg80211_mutex);
 356
 357         mutex_lock(&reg_regdb_search_mutex);
 358         while (!list_empty(&reg_regdb_search_list)) {
 359                 request = list_first_entry(&reg_regdb_search_list,
 360                                            struct reg_regdb_search_request,
 361                                            list);
 362                 list_del(&request->list);
 363
 364                 for (i=0; i<reg_regdb_size; i++) {
 365                         curdom = reg_regdb[i];
 366
 367                         if (!memcmp(request->alpha2, curdom->alpha2, 2)) {
 368                                 r = reg_copy_regd(&regdom, curdom);
 369                                 if (r)
 370                                         break;
 371                                 set_reg = true;
 372                                 break;
 373                         }
 374                 }
 375
 376                 kfree(request);
 377         }
 378         mutex_unlock(&reg_regdb_search_mutex);
 379
 380         if (set_reg)
 381                 set_regdom(regdom);
 382
 383         mutex_unlock(&cfg80211_mutex);
 384 }
 385
 386 static DECLARE_WORK(reg_regdb_work, reg_regdb_search);
 387
 388 static void reg_regdb_query(const char *alpha2)
 389 {
 390         struct reg_regdb_search_request *request;
 391
 392         if (!alpha2)
 393                 return;
 394
 395         request = kzalloc(sizeof(struct reg_regdb_search_request), GFP_KERNEL);
 396         if (!request)
 397                 return;
 398
 399         memcpy(request->alpha2, alpha2, 2);
 400
 401         mutex_lock(&reg_regdb_search_mutex);
 402         list_add_tail(&request->list, &reg_regdb_search_list);
 403         mutex_unlock(&reg_regdb_search_mutex);
 404
 405         schedule_work(&reg_regdb_work);
 406 }
 407
 408 /* Feel free to add any other sanity checks here */
 409 static void reg_regdb_size_check(void)
 410 {
 411         /* We should ideally BUILD_BUG_ON() but then random builds would fail */
 412         WARN_ONCE(!reg_regdb_size, "db.txt is empty, you should update it...");
 413 }
 414 #else
 415 static inline void reg_regdb_size_check(void) {}
 416 static inline void reg_regdb_query(const char *alpha2) {}
 417 #endif /* CONFIG_CFG80211_INTERNAL_REGDB */
 418
 419 /*
 420  * This lets us keep regulatory code which is updated on a regulatory
 421  * basis in userspace. Country information is filled in by
 422  * reg_device_uevent
 423  */
 424 static int call_crda(const char *alpha2)
 425 {
 426         if (!is_world_regdom((char *) alpha2))
 427                 pr_info("Calling CRDA for country: %c%c\n",
 428                         alpha2[0], alpha2[1]);
 429         else
 430                 pr_info("Calling CRDA to update world regulatory domain\n");
 431
 432         /* query internal regulatory database (if it exists) */
 433         reg_regdb_query(alpha2);
 434
 435         return kobject_uevent(&reg_pdev->dev.kobj, KOBJ_CHANGE);
 436 }
 437
 438 /* Used by nl80211 before kmalloc'ing our regulatory domain */
 439 bool reg_is_valid_request(const char *alpha2)
 440 {
 441         assert_cfg80211_lock();
 442
 443         if (!last_request)
 444                 return false;
 445
 446         return alpha2_equal(last_request->alpha2, alpha2);
 447 }
 448
 449 /* Sanity check on a regulatory rule */
 450 static bool is_valid_reg_rule(const struct ieee80211_reg_rule *rule)
 451 {
 452         const struct ieee80211_freq_range *freq_range = &rule->freq_range;
 453         u32 freq_diff;
 454
 455         if (freq_range->start_freq_khz <= 0 || freq_range->end_freq_khz <= 0)
 456                 return false;
 457
 458         if (freq_range->start_freq_khz > freq_range->end_freq_khz)
 459                 return false;
 460
 461         freq_diff = freq_range->end_freq_khz - freq_range->start_freq_khz;
 462
 463         if (freq_range->end_freq_khz <= freq_range->start_freq_khz ||
 464                         freq_range->max_bandwidth_khz > freq_diff)
 465                 return false;
 466
 467         return true;
 468 }
 469
 470 static bool is_valid_rd(const struct ieee80211_regdomain *rd)
 471 {
 472         const struct ieee80211_reg_rule *reg_rule = NULL;
 473         unsigned int i;
 474
 475         if (!rd->n_reg_rules)
 476                 return false;
 477
 478         if (WARN_ON(rd->n_reg_rules > NL80211_MAX_SUPP_REG_RULES))
 479                 return false;
 480
 481         for (i = 0; i < rd->n_reg_rules; i++) {
 482                 reg_rule = &rd->reg_rules[i];
 483                 if (!is_valid_reg_rule(reg_rule))
 484                         return false;
 485         }
 486
 487         return true;
 488 }
 489
 490 static bool reg_does_bw_fit(const struct ieee80211_freq_range *freq_range,
 491                             u32 center_freq_khz,
 492                             u32 bw_khz)
 493 {
 494         u32 start_freq_khz, end_freq_khz;
 495
 496         start_freq_khz = center_freq_khz - (bw_khz/2);
 497         end_freq_khz = center_freq_khz + (bw_khz/2);
 498
 499         if (start_freq_khz >= freq_range->start_freq_khz &&
 500             end_freq_khz <= freq_range->end_freq_khz)
 501                 return true;
 502
 503         return false;
 504 }
 505
 506 /**
 507  * freq_in_rule_band - tells us if a frequency is in a frequency band
 508  * @freq_range: frequency rule we want to query
 509  * @freq_khz: frequency we are inquiring about
 510  *
 511  * This lets us know if a specific frequency rule is or is not relevant to
 512  * a specific frequency's band. Bands are device specific and artificial
 513  * definitions (the "2.4 GHz band", the "5 GHz band" and the "60GHz band"),
 514  * however it is safe for now to assume that a frequency rule should not be
 515  * part of a frequency's band if the start freq or end freq are off by more
 516  * than 2 GHz for the 2.4 and 5 GHz bands, and by more than 10 GHz for the
 517  * 60 GHz band.
 518  * This resolution can be lowered and should be considered as we add
 519  * regulatory rule support for other "bands".
 520  **/
 521 static bool freq_in_rule_band(const struct ieee80211_freq_range *freq_range,
 522         u32 freq_khz)
 523 {
 524 #define ONE_GHZ_IN_KHZ  1000000
 525         /*
 526          * From 802.11ad: directional multi-gigabit (DMG):
 527          * Pertaining to operation in a frequency band containing a channel
 528          * with the Channel starting frequency above 45 GHz.
 529          */
 530         u32 limit = freq_khz > 45 * ONE_GHZ_IN_KHZ ?
 531                         10 * ONE_GHZ_IN_KHZ : 2 * ONE_GHZ_IN_KHZ;
 532         if (abs(freq_khz - freq_range->start_freq_khz) <= limit)
 533                 return true;
 534         if (abs(freq_khz - freq_range->end_freq_khz) <= limit)
 535                 return true;
 536         return false;
 537 #undef ONE_GHZ_IN_KHZ
 538 }
 539
 540 /*
 541  * Helper for regdom_intersect(), this does the real
 542  * mathematical intersection fun
 543  */
 544 static int reg_rules_intersect(
 545         const struct ieee80211_reg_rule *rule1,
 546         const struct ieee80211_reg_rule *rule2,
 547         struct ieee80211_reg_rule *intersected_rule)
 548 {
 549         const struct ieee80211_freq_range *freq_range1, *freq_range2;
 550         struct ieee80211_freq_range *freq_range;
 551         const struct ieee80211_power_rule *power_rule1, *power_rule2;
 552         struct ieee80211_power_rule *power_rule;
 553         u32 freq_diff;
 554
 555         freq_range1 = &rule1->freq_range;
 556         freq_range2 = &rule2->freq_range;
 557         freq_range = &intersected_rule->freq_range;
 558
 559         power_rule1 = &rule1->power_rule;
 560         power_rule2 = &rule2->power_rule;
 561         power_rule = &intersected_rule->power_rule;
 562
 563         freq_range->start_freq_khz = max(freq_range1->start_freq_khz,
 564                 freq_range2->start_freq_khz);
 565         freq_range->end_freq_khz = min(freq_range1->end_freq_khz,
 566                 freq_range2->end_freq_khz);
 567         freq_range->max_bandwidth_khz = min(freq_range1->max_bandwidth_khz,
 568                 freq_range2->max_bandwidth_khz);
 569
 570         freq_diff = freq_range->end_freq_khz - freq_range->start_freq_khz;
 571         if (freq_range->max_bandwidth_khz > freq_diff)
 572                 freq_range->max_bandwidth_khz = freq_diff;
 573
 574         power_rule->max_eirp = min(power_rule1->max_eirp,
 575                 power_rule2->max_eirp);
 576         power_rule->max_antenna_gain = min(power_rule1->max_antenna_gain,
 577                 power_rule2->max_antenna_gain);
 578
 579         intersected_rule->flags = (rule1->flags | rule2->flags);
 580
 581         if (!is_valid_reg_rule(intersected_rule))
 582                 return -EINVAL;
 583
 584         return 0;
 585 }
 586
 587 /**
 588  * regdom_intersect - do the intersection between two regulatory domains
 589  * @rd1: first regulatory domain
 590  * @rd2: second regulatory domain
 591  *
 592  * Use this function to get the intersection between two regulatory domains.
 593  * Once completed we will mark the alpha2 for the rd as intersected, "98",
 594  * as no one single alpha2 can represent this regulatory domain.
 595  *
 596  * Returns a pointer to the regulatory domain structure which will hold the
 597  * resulting intersection of rules between rd1 and rd2. We will
 598  * kzalloc() this structure for you.
 599  */
 600 static struct ieee80211_regdomain *regdom_intersect(
 601         const struct ieee80211_regdomain *rd1,
 602         const struct ieee80211_regdomain *rd2)
 603 {
 604         int r, size_of_regd;
 605         unsigned int x, y;
 606         unsigned int num_rules = 0, rule_idx = 0;
 607         const struct ieee80211_reg_rule *rule1, *rule2;
 608         struct ieee80211_reg_rule *intersected_rule;
 609         struct ieee80211_regdomain *rd;
 610         /* This is just a dummy holder to help us count */
 611         struct ieee80211_reg_rule irule;
 612
 613         /* Uses the stack temporarily for counter arithmetic */
 614         intersected_rule = &irule;
 615
 616         memset(intersected_rule, 0, sizeof(struct ieee80211_reg_rule));
 617
 618         if (!rd1 || !rd2)
 619                 return NULL;
 620
 621         /*
 622          * First we get a count of the rules we'll need, then we actually
 623          * build them. This is to so we can malloc() and free() a
 624          * regdomain once. The reason we use reg_rules_intersect() here
 625          * is it will return -EINVAL if the rule computed makes no sense.
 626          * All rules that do check out OK are valid.
 627          */
 628
 629         for (x = 0; x < rd1->n_reg_rules; x++) {
 630                 rule1 = &rd1->reg_rules[x];
 631                 for (y = 0; y < rd2->n_reg_rules; y++) {
 632                         rule2 = &rd2->reg_rules[y];
 633                         if (!reg_rules_intersect(rule1, rule2,
 634                                         intersected_rule))
 635                                 num_rules++;
 636                         memset(intersected_rule, 0,
 637                                         sizeof(struct ieee80211_reg_rule));
 638                 }
 639         }
 640
 641         if (!num_rules)
 642                 return NULL;
 643
 644         size_of_regd = sizeof(struct ieee80211_regdomain) +
 645                 ((num_rules + 1) * sizeof(struct ieee80211_reg_rule));
 646
 647         rd = kzalloc(size_of_regd, GFP_KERNEL);
 648         if (!rd)
 649                 return NULL;
 650
 651         for (x = 0; x < rd1->n_reg_rules; x++) {
 652                 rule1 = &rd1->reg_rules[x];
 653                 for (y = 0; y < rd2->n_reg_rules; y++) {
 654                         rule2 = &rd2->reg_rules[y];
 655                         /*
 656                          * This time around instead of using the stack lets
 657                          * write to the target rule directly saving ourselves
 658                          * a memcpy()
 659                          */
 660                         intersected_rule = &rd->reg_rules[rule_idx];
 661                         r = reg_rules_intersect(rule1, rule2,
 662                                 intersected_rule);
 663                         /*
 664                          * No need to memset here the intersected rule here as
 665                          * we're not using the stack anymore
 666                          */
 667                         if (r)
 668                                 continue;
 669                         rule_idx++;
 670                 }
 671         }
 672
 673         if (rule_idx != num_rules) {
 674                 kfree(rd);
 675                 return NULL;
 676         }
 677
 678         rd->n_reg_rules = num_rules;
 679         rd->alpha2[0] = '9';
 680         rd->alpha2[1] = '8';
 681
 682         return rd;
 683 }
 684
 685 /*
 686  * XXX: add support for the rest of enum nl80211_reg_rule_flags, we may
 687  * want to just have the channel structure use these
 688  */
 689 static u32 map_regdom_flags(u32 rd_flags)
 690 {
 691         u32 channel_flags = 0;
 692         if (rd_flags & NL80211_RRF_PASSIVE_SCAN)
 693                 channel_flags |= IEEE80211_CHAN_PASSIVE_SCAN;
 694         if (rd_flags & NL80211_RRF_NO_IBSS)
 695                 channel_flags |= IEEE80211_CHAN_NO_IBSS;
 696         if (rd_flags & NL80211_RRF_DFS)
 697                 channel_flags |= IEEE80211_CHAN_RADAR;
 698         if (rd_flags & NL80211_RRF_NO_OFDM)
 699                 channel_flags |= IEEE80211_CHAN_NO_OFDM;
 700         return channel_flags;
 701 }
 702
 703 static int freq_reg_info_regd(struct wiphy *wiphy,
 704                               u32 center_freq,
 705                               u32 desired_bw_khz,
 706                               const struct ieee80211_reg_rule **reg_rule,
 707                               const struct ieee80211_regdomain *custom_regd)
 708 {
 709         int i;
 710         bool band_rule_found = false;
 711         const struct ieee80211_regdomain *regd;
 712         bool bw_fits = false;
 713
 714         if (!desired_bw_khz)
 715                 desired_bw_khz = MHZ_TO_KHZ(20);
 716
 717         regd = custom_regd ? custom_regd : cfg80211_regdomain;
 718
 719         /*
 720          * Follow the driver's regulatory domain, if present, unless a country
 721          * IE has been processed or a user wants to help complaince further
 722          */
 723         if (!custom_regd &&
 724             last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE &&
 725             last_request->initiator != NL80211_REGDOM_SET_BY_USER &&
 726             wiphy->regd)
 727                 regd = wiphy->regd;
 728
 729         if (!regd)
 730                 return -EINVAL;
 731
 732         for (i = 0; i < regd->n_reg_rules; i++) {
 733                 const struct ieee80211_reg_rule *rr;
 734                 const struct ieee80211_freq_range *fr = NULL;
 735
 736                 rr = &regd->reg_rules[i];
 737                 fr = &rr->freq_range;
 738
 739                 /*
 740                  * We only need to know if one frequency rule was
 741                  * was in center_freq's band, that's enough, so lets
 742                  * not overwrite it once found
 743                  */
 744                 if (!band_rule_found)
 745                         band_rule_found = freq_in_rule_band(fr, center_freq);
 746
 747                 bw_fits = reg_does_bw_fit(fr,
 748                                           center_freq,
 749                                           desired_bw_khz);
 750
 751                 if (band_rule_found && bw_fits) {
 752                         *reg_rule = rr;
 753                         return 0;
 754                 }
 755         }
 756
 757         if (!band_rule_found)
 758                 return -ERANGE;
 759
 760         return -EINVAL;
 761 }
 762
 763 int freq_reg_info(struct wiphy *wiphy,
 764                   u32 center_freq,
 765                   u32 desired_bw_khz,
 766                   const struct ieee80211_reg_rule **reg_rule)
 767 {
 768         assert_cfg80211_lock();
 769         return freq_reg_info_regd(wiphy,
 770                                   center_freq,
 771                                   desired_bw_khz,
 772                                   reg_rule,
 773                                   NULL);
 774 }
 775 EXPORT_SYMBOL(freq_reg_info);
 776
 777 #ifdef CONFIG_CFG80211_REG_DEBUG
 778 static const char *reg_initiator_name(enum nl80211_reg_initiator initiator)
 779 {
 780         switch (initiator) {
 781         case NL80211_REGDOM_SET_BY_CORE:
 782                 return "Set by core";
 783         case NL80211_REGDOM_SET_BY_USER:
 784                 return "Set by user";
 785         case NL80211_REGDOM_SET_BY_DRIVER:
 786                 return "Set by driver";
 787         case NL80211_REGDOM_SET_BY_COUNTRY_IE:
 788                 return "Set by country IE";
 789         default:
 790                 WARN_ON(1);
 791                 return "Set by bug";
 792         }
 793 }
 794
 795 static void chan_reg_rule_print_dbg(struct ieee80211_channel *chan,
 796                                     u32 desired_bw_khz,
 797                                     const struct ieee80211_reg_rule *reg_rule)
 798 {
 799         const struct ieee80211_power_rule *power_rule;
 800         const struct ieee80211_freq_range *freq_range;
 801         char max_antenna_gain[32];
 802
 803         power_rule = &reg_rule->power_rule;
 804         freq_range = &reg_rule->freq_range;
 805
 806         if (!power_rule->max_antenna_gain)
 807                 snprintf(max_antenna_gain, 32, "N/A");
 808         else
 809                 snprintf(max_antenna_gain, 32, "%d", power_rule->max_antenna_gain);
 810
 811         REG_DBG_PRINT("Updating information on frequency %d MHz "
 812                       "for a %d MHz width channel with regulatory rule:\n",
 813                       chan->center_freq,
 814                       KHZ_TO_MHZ(desired_bw_khz));
 815
 816         REG_DBG_PRINT("%d KHz - %d KHz @ %d KHz), (%s mBi, %d mBm)\n",
 817                       freq_range->start_freq_khz,
 818                       freq_range->end_freq_khz,
 819                       freq_range->max_bandwidth_khz,
 820                       max_antenna_gain,
 821                       power_rule->max_eirp);
 822 }
 823 #else
 824 static void chan_reg_rule_print_dbg(struct ieee80211_channel *chan,
 825                                     u32 desired_bw_khz,
 826                                     const struct ieee80211_reg_rule *reg_rule)
 827 {
 828         return;
 829 }
 830 #endif
 831
 832 /*
 833  * Note that right now we assume the desired channel bandwidth
 834  * is always 20 MHz for each individual channel (HT40 uses 20 MHz
 835  * per channel, the primary and the extension channel). To support
 836  * smaller custom bandwidths such as 5 MHz or 10 MHz we'll need a
 837  * new ieee80211_channel.target_bw and re run the regulatory check
 838  * on the wiphy with the target_bw specified. Then we can simply use
 839  * that below for the desired_bw_khz below.
 840  */
 841 static void handle_channel(struct wiphy *wiphy,
 842                            enum nl80211_reg_initiator initiator,
 843                            enum ieee80211_band band,
 844                            unsigned int chan_idx)
 845 {
 846         int r;
 847         u32 flags, bw_flags = 0;
 848         u32 desired_bw_khz = MHZ_TO_KHZ(20);
 849         const struct ieee80211_reg_rule *reg_rule = NULL;
 850         const struct ieee80211_power_rule *power_rule = NULL;
 851         const struct ieee80211_freq_range *freq_range = NULL;
 852         struct ieee80211_supported_band *sband;
 853         struct ieee80211_channel *chan;
 854         struct wiphy *request_wiphy = NULL;
 855
 856         assert_cfg80211_lock();
 857
 858         request_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);
 859
 860         sband = wiphy->bands[band];
 861         BUG_ON(chan_idx >= sband->n_channels);
 862         chan = &sband->channels[chan_idx];
 863
 864         flags = chan->orig_flags;
 865
 866         r = freq_reg_info(wiphy,
 867                           MHZ_TO_KHZ(chan->center_freq),
 868                           desired_bw_khz,
 869                           &reg_rule);
 870
 871         if (r) {
 872                 /*
 873                  * We will disable all channels that do not match our
 874                  * received regulatory rule unless the hint is coming
 875                  * from a Country IE and the Country IE had no information
 876                  * about a band. The IEEE 802.11 spec allows for an AP
 877                  * to send only a subset of the regulatory rules allowed,
 878                  * so an AP in the US that only supports 2.4 GHz may only send
 879                  * a country IE with information for the 2.4 GHz band
 880                  * while 5 GHz is still supported.
 881                  */
 882                 if (initiator == NL80211_REGDOM_SET_BY_COUNTRY_IE &&
 883                     r == -ERANGE)
 884                         return;
 885
 886                 REG_DBG_PRINT("Disabling freq %d MHz\n", chan->center_freq);
 887                 chan->flags = IEEE80211_CHAN_DISABLED;
 888                 return;
 889         }
 890
 891         chan_reg_rule_print_dbg(chan, desired_bw_khz, reg_rule);
 892
 893         power_rule = &reg_rule->power_rule;
 894         freq_range = &reg_rule->freq_range;
 895
 896         if (freq_range->max_bandwidth_khz < MHZ_TO_KHZ(40))
 897                 bw_flags = IEEE80211_CHAN_NO_HT40;
 898
 899         if (last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER &&
 900             request_wiphy && request_wiphy == wiphy &&
 901             request_wiphy->flags & WIPHY_FLAG_STRICT_REGULATORY) {
 902                 /*
 903                  * This guarantees the driver's requested regulatory domain
 904                  * will always be used as a base for further regulatory
 905                  * settings
 906                  */
 907                 chan->flags = chan->orig_flags =
 908                         map_regdom_flags(reg_rule->flags) | bw_flags;
 909                 chan->max_antenna_gain = chan->orig_mag =
 910                         (int) MBI_TO_DBI(power_rule->max_antenna_gain);
 911                 chan->max_reg_power = chan->max_power = chan->orig_mpwr =
 912                         (int) MBM_TO_DBM(power_rule->max_eirp);
 913                 return;
 914         }
 915
 916         chan->beacon_found = false;
 917         chan->flags = flags | bw_flags | map_regdom_flags(reg_rule->flags);
 918         chan->max_antenna_gain = min(chan->orig_mag,
 919                 (int) MBI_TO_DBI(power_rule->max_antenna_gain));
 920         chan->max_reg_power = (int) MBM_TO_DBM(power_rule->max_eirp);
 921         if (chan->orig_mpwr) {
 922                 /*
 923                  * Devices that have their own custom regulatory domain
 924                  * but also use WIPHY_FLAG_STRICT_REGULATORY will follow the
 925                  * passed country IE power settings.
 926                  */
 927                 if (initiator == NL80211_REGDOM_SET_BY_COUNTRY_IE &&
 928                     wiphy->flags & WIPHY_FLAG_CUSTOM_REGULATORY &&
 929                     wiphy->flags & WIPHY_FLAG_STRICT_REGULATORY)
 930                         chan->max_power = chan->max_reg_power;
 931                 else
 932                         chan->max_power = min(chan->orig_mpwr,
 933                                               chan->max_reg_power);
 934         } else
 935                 chan->max_power = chan->max_reg_power;
 936 }
 937
 938 static void handle_band(struct wiphy *wiphy,
 939                         enum ieee80211_band band,
 940                         enum nl80211_reg_initiator initiator)
 941 {
 942         unsigned int i;
 943         struct ieee80211_supported_band *sband;
 944
 945         BUG_ON(!wiphy->bands[band]);
 946         sband = wiphy->bands[band];
 947
 948         for (i = 0; i < sband->n_channels; i++)
 949                 handle_channel(wiphy, initiator, band, i);
 950 }
 951
 952 static bool reg_request_cell_base(struct regulatory_request *request)
 953 {
 954         if (request->initiator != NL80211_REGDOM_SET_BY_USER)
 955                 return false;
 956         if (request->user_reg_hint_type != NL80211_USER_REG_HINT_CELL_BASE)
 957                 return false;
 958         return true;
 959 }
 960
 961 bool reg_last_request_cell_base(void)
 962 {
 963         bool val;
 964         assert_cfg80211_lock();
 965
 966         mutex_lock(&reg_mutex);
 967         val = reg_request_cell_base(last_request);
 968         mutex_unlock(&reg_mutex);
 969         return val;
 970 }
 971
 972 #ifdef CONFIG_CFG80211_CERTIFICATION_ONUS
 973
 974 /* Core specific check */
 975 static int reg_ignore_cell_hint(struct regulatory_request *pending_request)
 976 {
 977         if (!reg_num_devs_support_basehint)
 978                 return -EOPNOTSUPP;
 979
 980         if (reg_request_cell_base(last_request)) {
 981                 if (!regdom_changes(pending_request->alpha2))
 982                         return -EALREADY;
 983                 return 0;
 984         }
 985         return 0;
 986 }
 987
 988 /* Device specific check */
 989 static bool reg_dev_ignore_cell_hint(struct wiphy *wiphy)
 990 {
 991         if (!(wiphy->features & NL80211_FEATURE_CELL_BASE_REG_HINTS))
 992                 return true;
 993         return false;
 994 }
 995 #else
 996 static int reg_ignore_cell_hint(struct regulatory_request *pending_request)
 997 {
 998         return -EOPNOTSUPP;
 999 }
1000 static int reg_dev_ignore_cell_hint(struct wiphy *wiphy)
1001 {
1002         return true;
1003 }
1004 #endif
1005
1006
1007 static bool ignore_reg_update(struct wiphy *wiphy,
1008                               enum nl80211_reg_initiator initiator)
1009 {
1010         if (!last_request) {
1011                 REG_DBG_PRINT("Ignoring regulatory request %s since "
1012                               "last_request is not set\n",
1013                               reg_initiator_name(initiator));
1014                 return true;
1015         }
1016
1017         if (initiator == NL80211_REGDOM_SET_BY_CORE &&
1018             wiphy->flags & WIPHY_FLAG_CUSTOM_REGULATORY) {
1019                 REG_DBG_PRINT("Ignoring regulatory request %s "
1020                               "since the driver uses its own custom "
1021                               "regulatory domain\n",
1022                               reg_initiator_name(initiator));
1023                 return true;
1024         }
1025
1026         /*
1027          * wiphy->regd will be set once the device has its own
1028          * desired regulatory domain set
1029          */
1030         if (wiphy->flags & WIPHY_FLAG_STRICT_REGULATORY && !wiphy->regd &&
1031             initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE &&
1032             !is_world_regdom(last_request->alpha2)) {
1033                 REG_DBG_PRINT("Ignoring regulatory request %s "
1034                               "since the driver requires its own regulatory "
1035                               "domain to be set first\n",
1036                               reg_initiator_name(initiator));
1037                 return true;
1038         }
1039
1040         if (reg_request_cell_base(last_request))
1041                 return reg_dev_ignore_cell_hint(wiphy);
1042
1043         return false;
1044 }
1045
1046 static void handle_reg_beacon(struct wiphy *wiphy,
1047                               unsigned int chan_idx,
1048                               struct reg_beacon *reg_beacon)
1049 {
1050         struct ieee80211_supported_band *sband;
1051         struct ieee80211_channel *chan;
1052         bool channel_changed = false;
1053         struct ieee80211_channel chan_before;
1054
1055         assert_cfg80211_lock();
1056
1057         sband = wiphy->bands[reg_beacon->chan.band];
1058         chan = &sband->channels[chan_idx];
1059
1060         if (likely(chan->center_freq != reg_beacon->chan.center_freq))
1061                 return;
1062
1063         if (chan->beacon_found)
1064                 return;
1065
1066         chan->beacon_found = true;
1067
1068         if (wiphy->flags & WIPHY_FLAG_DISABLE_BEACON_HINTS)
1069                 return;
1070
1071         chan_before.center_freq = chan->center_freq;
1072         chan_before.flags = chan->flags;
1073
1074         if (chan->flags & IEEE80211_CHAN_PASSIVE_SCAN) {
1075                 chan->flags &= ~IEEE80211_CHAN_PASSIVE_SCAN;
1076                 channel_changed = true;
1077         }
1078
1079         if (chan->flags & IEEE80211_CHAN_NO_IBSS) {
1080                 chan->flags &= ~IEEE80211_CHAN_NO_IBSS;
1081                 channel_changed = true;
1082         }
1083
1084         if (channel_changed)
1085                 nl80211_send_beacon_hint_event(wiphy, &chan_before, chan);
1086 }
1087
1088 /*
1089  * Called when a scan on a wiphy finds a beacon on
1090  * new channel
1091  */
1092 static void wiphy_update_new_beacon(struct wiphy *wiphy,
1093                                     struct reg_beacon *reg_beacon)
1094 {
1095         unsigned int i;
1096         struct ieee80211_supported_band *sband;
1097
1098         assert_cfg80211_lock();
1099
1100         if (!wiphy->bands[reg_beacon->chan.band])
1101                 return;
1102
1103         sband = wiphy->bands[reg_beacon->chan.band];
1104
1105         for (i = 0; i < sband->n_channels; i++)
1106                 handle_reg_beacon(wiphy, i, reg_beacon);
1107 }
1108
1109 /*
1110  * Called upon reg changes or a new wiphy is added
1111  */
1112 static void wiphy_update_beacon_reg(struct wiphy *wiphy)
1113 {
1114         unsigned int i;
1115         struct ieee80211_supported_band *sband;
1116         struct reg_beacon *reg_beacon;
1117
1118         assert_cfg80211_lock();
1119
1120         if (list_empty(&reg_beacon_list))
1121                 return;
1122
1123         list_for_each_entry(reg_beacon, &reg_beacon_list, list) {
1124                 if (!wiphy->bands[reg_beacon->chan.band])
1125                         continue;
1126                 sband = wiphy->bands[reg_beacon->chan.band];
1127                 for (i = 0; i < sband->n_channels; i++)
1128                         handle_reg_beacon(wiphy, i, reg_beacon);
1129         }
1130 }
1131
1132 static bool reg_is_world_roaming(struct wiphy *wiphy)
1133 {
1134         if (is_world_regdom(cfg80211_regdomain->alpha2) ||
1135             (wiphy->regd && is_world_regdom(wiphy->regd->alpha2)))
1136                 return true;
1137         if (last_request &&
1138             last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE &&
1139             wiphy->flags & WIPHY_FLAG_CUSTOM_REGULATORY)
1140                 return true;
1141         return false;
1142 }
1143
1144 /* Reap the advantages of previously found beacons */
1145 static void reg_process_beacons(struct wiphy *wiphy)
1146 {
1147         /*
1148          * Means we are just firing up cfg80211, so no beacons would
1149          * have been processed yet.
1150          */
1151         if (!last_request)
1152                 return;
1153         if (!reg_is_world_roaming(wiphy))
1154                 return;
1155         wiphy_update_beacon_reg(wiphy);
1156 }
1157
1158 static bool is_ht40_not_allowed(struct ieee80211_channel *chan)
1159 {
1160         if (!chan)
1161                 return true;
1162         if (chan->flags & IEEE80211_CHAN_DISABLED)
1163                 return true;
1164         /* This would happen when regulatory rules disallow HT40 completely */
1165         if (IEEE80211_CHAN_NO_HT40 == (chan->flags & (IEEE80211_CHAN_NO_HT40)))
1166                 return true;
1167         return false;
1168 }
1169
1170 static void reg_process_ht_flags_channel(struct wiphy *wiphy,
1171                                          enum ieee80211_band band,
1172                                          unsigned int chan_idx)
1173 {
1174         struct ieee80211_supported_band *sband;
1175         struct ieee80211_channel *channel;
1176         struct ieee80211_channel *channel_before = NULL, *channel_after = NULL;
1177         unsigned int i;
1178
1179         assert_cfg80211_lock();
1180
1181         sband = wiphy->bands[band];
1182         BUG_ON(chan_idx >= sband->n_channels);
1183         channel = &sband->channels[chan_idx];
1184
1185         if (is_ht40_not_allowed(channel)) {
1186                 channel->flags |= IEEE80211_CHAN_NO_HT40;
1187                 return;
1188         }
1189
1190         /*
1191          * We need to ensure the extension channels exist to
1192          * be able to use HT40- or HT40+, this finds them (or not)
1193          */
1194         for (i = 0; i < sband->n_channels; i++) {
1195                 struct ieee80211_channel *c = &sband->channels[i];
1196                 if (c->center_freq == (channel->center_freq - 20))
1197                         channel_before = c;
1198                 if (c->center_freq == (channel->center_freq + 20))
1199                         channel_after = c;
1200         }
1201
1202         /*
1203          * Please note that this assumes target bandwidth is 20 MHz,
1204          * if that ever changes we also need to change the below logic
1205          * to include that as well.
1206          */
1207         if (is_ht40_not_allowed(channel_before))
1208                 channel->flags |= IEEE80211_CHAN_NO_HT40MINUS;
1209         else
1210                 channel->flags &= ~IEEE80211_CHAN_NO_HT40MINUS;
1211
1212         if (is_ht40_not_allowed(channel_after))
1213                 channel->flags |= IEEE80211_CHAN_NO_HT40PLUS;
1214         else
1215                 channel->flags &= ~IEEE80211_CHAN_NO_HT40PLUS;
1216 }
1217
1218 static void reg_process_ht_flags_band(struct wiphy *wiphy,
1219                                       enum ieee80211_band band)
1220 {
1221         unsigned int i;
1222         struct ieee80211_supported_band *sband;
1223
1224         BUG_ON(!wiphy->bands[band]);
1225         sband = wiphy->bands[band];
1226
1227         for (i = 0; i < sband->n_channels; i++)
1228                 reg_process_ht_flags_channel(wiphy, band, i);
1229 }
1230
1231 static void reg_process_ht_flags(struct wiphy *wiphy)
1232 {
1233         enum ieee80211_band band;
1234
1235         if (!wiphy)
1236                 return;
1237
1238         for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
1239                 if (wiphy->bands[band])
1240                         reg_process_ht_flags_band(wiphy, band);
1241         }
1242
1243 }
1244
1245 static void wiphy_update_regulatory(struct wiphy *wiphy,
1246                                     enum nl80211_reg_initiator initiator)
1247 {
1248         enum ieee80211_band band;
1249
1250         assert_reg_lock();
1251
1252         if (ignore_reg_update(wiphy, initiator))
1253                 return;
1254
1255         last_request->dfs_region = cfg80211_regdomain->dfs_region;
1256
1257         for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
1258                 if (wiphy->bands[band])
1259                         handle_band(wiphy, band, initiator);
1260         }
1261
1262         reg_process_beacons(wiphy);
1263         reg_process_ht_flags(wiphy);
1264         if (wiphy->reg_notifier)
1265                 wiphy->reg_notifier(wiphy, last_request);
1266 }
1267
1268 static void update_all_wiphy_regulatory(enum nl80211_reg_initiator initiator)
1269 {
1270         struct cfg80211_registered_device *rdev;
1271         struct wiphy *wiphy;
1272
1273         list_for_each_entry(rdev, &cfg80211_rdev_list, list) {
1274                 wiphy = &rdev->wiphy;
1275                 wiphy_update_regulatory(wiphy, initiator);
1276                 /*
1277                  * Regulatory updates set by CORE are ignored for custom
1278                  * regulatory cards. Let us notify the changes to the driver,
1279                  * as some drivers used this to restore its orig_* reg domain.
1280                  */
1281                 if (initiator == NL80211_REGDOM_SET_BY_CORE &&
1282                     wiphy->flags & WIPHY_FLAG_CUSTOM_REGULATORY &&
1283                     wiphy->reg_notifier)
1284                         wiphy->reg_notifier(wiphy, last_request);
1285         }
1286 }
1287
1288 static void handle_channel_custom(struct wiphy *wiphy,
1289                                   enum ieee80211_band band,
1290                                   unsigned int chan_idx,
1291                                   const struct ieee80211_regdomain *regd)
1292 {
1293         int r;
1294         u32 desired_bw_khz = MHZ_TO_KHZ(20);
1295         u32 bw_flags = 0;
1296         const struct ieee80211_reg_rule *reg_rule = NULL;
1297         const struct ieee80211_power_rule *power_rule = NULL;
1298         const struct ieee80211_freq_range *freq_range = NULL;
1299         struct ieee80211_supported_band *sband;
1300         struct ieee80211_channel *chan;
1301
1302         assert_reg_lock();
1303
1304         sband = wiphy->bands[band];
1305         BUG_ON(chan_idx >= sband->n_channels);
1306         chan = &sband->channels[chan_idx];
1307
1308         r = freq_reg_info_regd(wiphy,
1309                                MHZ_TO_KHZ(chan->center_freq),
1310                                desired_bw_khz,
1311                                &reg_rule,
1312                                regd);
1313
1314         if (r) {
1315                 REG_DBG_PRINT("Disabling freq %d MHz as custom "
1316                               "regd has no rule that fits a %d MHz "
1317                               "wide channel\n",
1318                               chan->center_freq,
1319                               KHZ_TO_MHZ(desired_bw_khz));
1320                 chan->flags = IEEE80211_CHAN_DISABLED;
1321                 return;
1322         }
1323
1324         chan_reg_rule_print_dbg(chan, desired_bw_khz, reg_rule);
1325
1326         power_rule = &reg_rule->power_rule;
1327         freq_range = &reg_rule->freq_range;
1328
1329         if (freq_range->max_bandwidth_khz < MHZ_TO_KHZ(40))
1330                 bw_flags = IEEE80211_CHAN_NO_HT40;
1331
1332         chan->flags |= map_regdom_flags(reg_rule->flags) | bw_flags;
1333         chan->max_antenna_gain = (int) MBI_TO_DBI(power_rule->max_antenna_gain);
1334         chan->max_reg_power = chan->max_power =
1335                 (int) MBM_TO_DBM(power_rule->max_eirp);
1336 }
1337
1338 static void handle_band_custom(struct wiphy *wiphy, enum ieee80211_band band,
1339                                const struct ieee80211_regdomain *regd)
1340 {
1341         unsigned int i;
1342         struct ieee80211_supported_band *sband;
1343
1344         BUG_ON(!wiphy->bands[band]);
1345         sband = wiphy->bands[band];
1346
1347         for (i = 0; i < sband->n_channels; i++)
1348                 handle_channel_custom(wiphy, band, i, regd);
1349 }
1350
1351 /* Used by drivers prior to wiphy registration */
1352 void wiphy_apply_custom_regulatory(struct wiphy *wiphy,
1353                                    const struct ieee80211_regdomain *regd)
1354 {
1355         enum ieee80211_band band;
1356         unsigned int bands_set = 0;
1357
1358         mutex_lock(&reg_mutex);
1359         for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
1360                 if (!wiphy->bands[band])
1361                         continue;
1362                 handle_band_custom(wiphy, band, regd);
1363                 bands_set++;
1364         }
1365         mutex_unlock(&reg_mutex);
1366
1367         /*
1368          * no point in calling this if it won't have any effect
1369          * on your device's supportd bands.
1370          */
1371         WARN_ON(!bands_set);
1372 }
1373 EXPORT_SYMBOL(wiphy_apply_custom_regulatory);
1374
1375 /*
1376  * Return value which can be used by ignore_request() to indicate
1377  * it has been determined we should intersect two regulatory domains
1378  */
1379 #define REG_INTERSECT   1
1380
1381 /* This has the logic which determines when a new request
1382  * should be ignored. */
1383 static int ignore_request(struct wiphy *wiphy,
1384                           struct regulatory_request *pending_request)
1385 {
1386         struct wiphy *last_wiphy = NULL;
1387
1388         assert_cfg80211_lock();
1389
1390         /* All initial requests are respected */
1391         if (!last_request)
1392                 return 0;
1393
1394         switch (pending_request->initiator) {
1395         case NL80211_REGDOM_SET_BY_CORE:
1396                 return 0;
1397         case NL80211_REGDOM_SET_BY_COUNTRY_IE:
1398
1399                 if (reg_request_cell_base(last_request)) {
1400                         /* Trust a Cell base station over the AP's country IE */
1401                         if (regdom_changes(pending_request->alpha2))
1402                                 return -EOPNOTSUPP;
1403                         return -EALREADY;
1404                 }
1405
1406                 last_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);
1407
1408                 if (unlikely(!is_an_alpha2(pending_request->alpha2)))
1409                         return -EINVAL;
1410                 if (last_request->initiator ==
1411                     NL80211_REGDOM_SET_BY_COUNTRY_IE) {
1412                         if (last_wiphy != wiphy) {
1413                                 /*
1414                                  * Two cards with two APs claiming different
1415                                  * Country IE alpha2s. We could
1416                                  * intersect them, but that seems unlikely
1417                                  * to be correct. Reject second one for now.
1418                                  */
1419                                 if (regdom_changes(pending_request->alpha2))
1420                                         return -EOPNOTSUPP;
1421                                 return -EALREADY;
1422                         }
1423                         /*
1424                          * Two consecutive Country IE hints on the same wiphy.
1425                          * This should be picked up early by the driver/stack
1426                          */
1427                         if (WARN_ON(regdom_changes(pending_request->alpha2)))
1428                                 return 0;
1429                         return -EALREADY;
1430                 }
1431                 return 0;
1432         case NL80211_REGDOM_SET_BY_DRIVER:
1433                 if (last_request->initiator == NL80211_REGDOM_SET_BY_CORE) {
1434                         if (regdom_changes(pending_request->alpha2))
1435                                 return 0;
1436                         return -EALREADY;
1437                 }
1438
1439                 /*
1440                  * This would happen if you unplug and plug your card
1441                  * back in or if you add a new device for which the previously
1442                  * loaded card also agrees on the regulatory domain.
1443                  */
1444                 if (last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER &&
1445                     !regdom_changes(pending_request->alpha2))
1446                         return -EALREADY;
1447
1448                 return REG_INTERSECT;
1449         case NL80211_REGDOM_SET_BY_USER:
1450                 if (reg_request_cell_base(pending_request))
1451                         return reg_ignore_cell_hint(pending_request);
1452
1453                 if (reg_request_cell_base(last_request))
1454                         return -EOPNOTSUPP;
1455
1456                 if (last_request->initiator == NL80211_REGDOM_SET_BY_COUNTRY_IE)
1457                         return REG_INTERSECT;
1458                 /*
1459                  * If the user knows better the user should set the regdom
1460                  * to their country before the IE is picked up
1461                  */
1462                 if (last_request->initiator == NL80211_REGDOM_SET_BY_USER &&
1463                           last_request->intersect)
1464                         return -EOPNOTSUPP;
1465                 /*
1466                  * Process user requests only after previous user/driver/core
1467                  * requests have been processed
1468                  */
1469                 if (last_request->initiator == NL80211_REGDOM_SET_BY_CORE ||
1470                     last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER ||
1471                     last_request->initiator == NL80211_REGDOM_SET_BY_USER) {
1472                         if (regdom_changes(last_request->alpha2))
1473                                 return -EAGAIN;
1474                 }
1475
1476                 if (!regdom_changes(pending_request->alpha2))
1477                         return -EALREADY;
1478
1479                 return 0;
1480         }
1481
1482         return -EINVAL;
1483 }
1484
1485 static void reg_set_request_processed(void)
1486 {
1487         bool need_more_processing = false;
1488
1489         last_request->processed = true;
1490
1491         spin_lock(&reg_requests_lock);
1492         if (!list_empty(&reg_requests_list))
1493                 need_more_processing = true;
1494         spin_unlock(&reg_requests_lock);
1495
1496         if (last_request->initiator == NL80211_REGDOM_SET_BY_USER)
1497                 cancel_delayed_work(&reg_timeout);
1498
1499         if (need_more_processing)
1500                 schedule_work(&reg_work);
1501 }
1502
1503 /**
1504  * __regulatory_hint - hint to the wireless core a regulatory domain
1505  * @wiphy: if the hint comes from country information from an AP, this
1506  *      is required to be set to the wiphy that received the information
1507  * @pending_request: the regulatory request currently being processed
1508  *
1509  * The Wireless subsystem can use this function to hint to the wireless core
1510  * what it believes should be the current regulatory domain.
1511  *
1512  * Returns zero if all went fine, %-EALREADY if a regulatory domain had
1513  * already been set or other standard error codes.
1514  *
1515  * Caller must hold &cfg80211_mutex and &reg_mutex
1516  */
1517 static int __regulatory_hint(struct wiphy *wiphy,
1518                              struct regulatory_request *pending_request)
1519 {
1520         bool intersect = false;
1521         int r = 0;
1522
1523         assert_cfg80211_lock();
1524
1525         r = ignore_request(wiphy, pending_request);
1526
1527         if (r == REG_INTERSECT) {
1528                 if (pending_request->initiator ==
1529                     NL80211_REGDOM_SET_BY_DRIVER) {
1530                         r = reg_copy_regd(&wiphy->regd, cfg80211_regdomain);
1531                         if (r) {
1532                                 kfree(pending_request);
1533                                 return r;
1534                         }
1535                 }
1536                 intersect = true;
1537         } else if (r) {
1538                 /*
1539                  * If the regulatory domain being requested by the
1540                  * driver has already been set just copy it to the
1541                  * wiphy
1542                  */
1543                 if (r == -EALREADY &&
1544                     pending_request->initiator ==
1545                     NL80211_REGDOM_SET_BY_DRIVER) {
1546                         r = reg_copy_regd(&wiphy->regd, cfg80211_regdomain);
1547                         if (r) {
1548                                 kfree(pending_request);
1549                                 return r;
1550                         }
1551                         r = -EALREADY;
1552                         goto new_request;
1553                 }
1554                 kfree(pending_request);
1555                 return r;
1556         }
1557
1558 new_request:
1559         if (last_request != &core_request_world)
1560                 kfree(last_request);
1561
1562         last_request = pending_request;
1563         last_request->intersect = intersect;
1564
1565         pending_request = NULL;
1566
1567         if (last_request->initiator == NL80211_REGDOM_SET_BY_USER) {
1568                 user_alpha2[0] = last_request->alpha2[0];
1569                 user_alpha2[1] = last_request->alpha2[1];
1570         }
1571
1572         /* When r == REG_INTERSECT we do need to call CRDA */
1573         if (r < 0) {
1574                 /*
1575                  * Since CRDA will not be called in this case as we already
1576                  * have applied the requested regulatory domain before we just
1577                  * inform userspace we have processed the request
1578                  */
1579                 if (r == -EALREADY) {
1580                         nl80211_send_reg_change_event(last_request);
1581                         reg_set_request_processed();
1582                 }
1583                 return r;
1584         }
1585
1586         return call_crda(last_request->alpha2);
1587 }
1588
1589 /* This processes *all* regulatory hints */
1590 static void reg_process_hint(struct regulatory_request *reg_request,
1591                              enum nl80211_reg_initiator reg_initiator)
1592 {
1593         int r = 0;
1594         struct wiphy *wiphy = NULL;
1595
1596         BUG_ON(!reg_request->alpha2);
1597
1598         if (wiphy_idx_valid(reg_request->wiphy_idx))
1599                 wiphy = wiphy_idx_to_wiphy(reg_request->wiphy_idx);
1600
1601         if (reg_initiator == NL80211_REGDOM_SET_BY_DRIVER &&
1602             !wiphy) {
1603                 kfree(reg_request);
1604                 return;
1605         }
1606
1607         r = __regulatory_hint(wiphy, reg_request);
1608         /* This is required so that the orig_* parameters are saved */
1609         if (r == -EALREADY && wiphy &&
1610             wiphy->flags & WIPHY_FLAG_STRICT_REGULATORY) {
1611                 wiphy_update_regulatory(wiphy, reg_initiator);
1612                 return;
1613         }
1614
1615         /*
1616          * We only time out user hints, given that they should be the only
1617          * source of bogus requests.
1618          */
1619         if (r != -EALREADY &&
1620             reg_initiator == NL80211_REGDOM_SET_BY_USER)
1621                 schedule_delayed_work(&reg_timeout, msecs_to_jiffies(3142));
1622 }
1623
1624 /*
1625  * Processes regulatory hints, this is all the NL80211_REGDOM_SET_BY_*
1626  * Regulatory hints come on a first come first serve basis and we
1627  * must process each one atomically.
1628  */
1629 static void reg_process_pending_hints(void)
1630 {
1631         struct regulatory_request *reg_request;
1632
1633         mutex_lock(&cfg80211_mutex);
1634         mutex_lock(&reg_mutex);
1635
1636         /* When last_request->processed becomes true this will be rescheduled */
1637         if (last_request && !last_request->processed) {
1638                 REG_DBG_PRINT("Pending regulatory request, waiting "
1639                               "for it to be processed...\n");
1640                 goto out;
1641         }
1642
1643         spin_lock(&reg_requests_lock);
1644
1645         if (list_empty(&reg_requests_list)) {
1646                 spin_unlock(&reg_requests_lock);
1647                 goto out;
1648         }
1649
1650         reg_request = list_first_entry(&reg_requests_list,
1651                                        struct regulatory_request,
1652                                        list);
1653         list_del_init(&reg_request->list);
1654
1655         spin_unlock(&reg_requests_lock);
1656
1657         reg_process_hint(reg_request, reg_request->initiator);
1658
1659 out:
1660         mutex_unlock(&reg_mutex);
1661         mutex_unlock(&cfg80211_mutex);
1662 }
1663
1664 /* Processes beacon hints -- this has nothing to do with country IEs */
1665 static void reg_process_pending_beacon_hints(void)
1666 {
1667         struct cfg80211_registered_device *rdev;
1668         struct reg_beacon *pending_beacon, *tmp;
1669
1670         /*
1671          * No need to hold the reg_mutex here as we just touch wiphys
1672          * and do not read or access regulatory variables.
1673          */
1674         mutex_lock(&cfg80211_mutex);
1675
1676         /* This goes through the _pending_ beacon list */
1677         spin_lock_bh(&reg_pending_beacons_lock);
1678
1679         if (list_empty(&reg_pending_beacons)) {
1680                 spin_unlock_bh(&reg_pending_beacons_lock);
1681                 goto out;
1682         }
1683
1684         list_for_each_entry_safe(pending_beacon, tmp,
1685                                  &reg_pending_beacons, list) {
1686
1687                 list_del_init(&pending_beacon->list);
1688
1689                 /* Applies the beacon hint to current wiphys */
1690                 list_for_each_entry(rdev, &cfg80211_rdev_list, list)
1691                         wiphy_update_new_beacon(&rdev->wiphy, pending_beacon);
1692
1693                 /* Remembers the beacon hint for new wiphys or reg changes */
1694                 list_add_tail(&pending_beacon->list, &reg_beacon_list);
1695         }
1696
1697         spin_unlock_bh(&reg_pending_beacons_lock);
1698 out:
1699         mutex_unlock(&cfg80211_mutex);
1700 }
1701
1702 static void reg_todo(struct work_struct *work)
1703 {
1704         reg_process_pending_hints();
1705         reg_process_pending_beacon_hints();
1706 }
1707
1708 static void queue_regulatory_request(struct regulatory_request *request)
1709 {
1710         if (isalpha(request->alpha2[0]))
1711                 request->alpha2[0] = toupper(request->alpha2[0]);
1712         if (isalpha(request->alpha2[1]))
1713                 request->alpha2[1] = toupper(request->alpha2[1]);
1714
1715         spin_lock(&reg_requests_lock);
1716         list_add_tail(&request->list, &reg_requests_list);
1717         spin_unlock(&reg_requests_lock);
1718
1719         schedule_work(&reg_work);
1720 }
1721
1722 /*
1723  * Core regulatory hint -- happens during cfg80211_init()
1724  * and when we restore regulatory settings.
1725  */
1726 static int regulatory_hint_core(const char *alpha2)
1727 {
1728         struct regulatory_request *request;
1729
1730         request = kzalloc(sizeof(struct regulatory_request),
1731                           GFP_KERNEL);
1732         if (!request)
1733                 return -ENOMEM;
1734
1735         request->alpha2[0] = alpha2[0];
1736         request->alpha2[1] = alpha2[1];
1737         request->initiator = NL80211_REGDOM_SET_BY_CORE;
1738
1739         queue_regulatory_request(request);
1740
1741         return 0;
1742 }
1743
1744 /* User hints */
1745 int regulatory_hint_user(const char *alpha2,
1746                          enum nl80211_user_reg_hint_type user_reg_hint_type)
1747 {
1748         struct regulatory_request *request;
1749
1750         BUG_ON(!alpha2);
1751
1752         request = kzalloc(sizeof(struct regulatory_request), GFP_KERNEL);
1753         if (!request)
1754                 return -ENOMEM;
1755
1756         request->wiphy_idx = WIPHY_IDX_STALE;
1757         request->alpha2[0] = alpha2[0];
1758         request->alpha2[1] = alpha2[1];
1759         request->initiator = NL80211_REGDOM_SET_BY_USER;
1760         request->user_reg_hint_type = user_reg_hint_type;
1761
1762         queue_regulatory_request(request);
1763
1764         return 0;
1765 }
1766
1767 /* Driver hints */
1768 int regulatory_hint(struct wiphy *wiphy, const char *alpha2)
1769 {
1770         struct regulatory_request *request;
1771
1772         BUG_ON(!alpha2);
1773         BUG_ON(!wiphy);
1774
1775         request = kzalloc(sizeof(struct regulatory_request), GFP_KERNEL);
1776         if (!request)
1777                 return -ENOMEM;
1778
1779         request->wiphy_idx = get_wiphy_idx(wiphy);
1780
1781         /* Must have registered wiphy first */
1782         BUG_ON(!wiphy_idx_valid(request->wiphy_idx));
1783
1784         request->alpha2[0] = alpha2[0];
1785         request->alpha2[1] = alpha2[1];
1786         request->initiator = NL80211_REGDOM_SET_BY_DRIVER;
1787
1788         queue_regulatory_request(request);
1789
1790         return 0;
1791 }
1792 EXPORT_SYMBOL(regulatory_hint);
1793
1794 /*
1795  * We hold wdev_lock() here so we cannot hold cfg80211_mutex() and
1796  * therefore cannot iterate over the rdev list here.
1797  */
1798 void regulatory_hint_11d(struct wiphy *wiphy,
1799                          enum ieee80211_band band,
1800                          u8 *country_ie,
1801                          u8 country_ie_len)
1802 {
1803         char alpha2[2];
1804         enum environment_cap env = ENVIRON_ANY;
1805         struct regulatory_request *request;
1806
1807         mutex_lock(&reg_mutex);
1808
1809         if (unlikely(!last_request))
1810                 goto out;
1811
1812         /* IE len must be evenly divisible by 2 */
1813         if (country_ie_len & 0x01)
1814                 goto out;
1815
1816         if (country_ie_len < IEEE80211_COUNTRY_IE_MIN_LEN)
1817                 goto out;
1818
1819         alpha2[0] = country_ie[0];
1820         alpha2[1] = country_ie[1];
1821
1822         if (country_ie[2] == 'I')
1823                 env = ENVIRON_INDOOR;
1824         else if (country_ie[2] == 'O')
1825                 env = ENVIRON_OUTDOOR;
1826
1827         /*
1828          * We will run this only upon a successful connection on cfg80211.
1829          * We leave conflict resolution to the workqueue, where can hold
1830          * cfg80211_mutex.
1831          */
1832         if (likely(last_request->initiator ==
1833             NL80211_REGDOM_SET_BY_COUNTRY_IE &&
1834             wiphy_idx_valid(last_request->wiphy_idx)))
1835                 goto out;
1836
1837         request = kzalloc(sizeof(struct regulatory_request), GFP_KERNEL);
1838         if (!request)
1839                 goto out;
1840
1841         request->wiphy_idx = get_wiphy_idx(wiphy);
1842         request->alpha2[0] = alpha2[0];
1843         request->alpha2[1] = alpha2[1];
1844         request->initiator = NL80211_REGDOM_SET_BY_COUNTRY_IE;
1845         request->country_ie_env = env;
1846
1847         mutex_unlock(&reg_mutex);
1848
1849         queue_regulatory_request(request);
1850
1851         return;
1852
1853 out:
1854         mutex_unlock(&reg_mutex);
1855 }
1856
1857 static void restore_alpha2(char *alpha2, bool reset_user)
1858 {
1859         /* indicates there is no alpha2 to consider for restoration */
1860         alpha2[0] = '9';
1861         alpha2[1] = '7';
1862
1863         /* The user setting has precedence over the module parameter */
1864         if (is_user_regdom_saved()) {
1865                 /* Unless we're asked to ignore it and reset it */
1866                 if (reset_user) {
1867                         REG_DBG_PRINT("Restoring regulatory settings "
1868                                "including user preference\n");
1869                         user_alpha2[0] = '9';
1870                         user_alpha2[1] = '7';
1871
1872                         /*
1873                          * If we're ignoring user settings, we still need to
1874                          * check the module parameter to ensure we put things
1875                          * back as they were for a full restore.
1876                          */
1877                         if (!is_world_regdom(ieee80211_regdom)) {
1878                                 REG_DBG_PRINT("Keeping preference on "
1879                                        "module parameter ieee80211_regdom: %c%c\n",
1880                                        ieee80211_regdom[0],
1881                                        ieee80211_regdom[1]);
1882                                 alpha2[0] = ieee80211_regdom[0];
1883                                 alpha2[1] = ieee80211_regdom[1];
1884                         }
1885                 } else {
1886                         REG_DBG_PRINT("Restoring regulatory settings "
1887                                "while preserving user preference for: %c%c\n",
1888                                user_alpha2[0],
1889                                user_alpha2[1]);
1890                         alpha2[0] = user_alpha2[0];
1891                         alpha2[1] = user_alpha2[1];
1892                 }
1893         } else if (!is_world_regdom(ieee80211_regdom)) {
1894                 REG_DBG_PRINT("Keeping preference on "
1895                        "module parameter ieee80211_regdom: %c%c\n",
1896                        ieee80211_regdom[0],
1897                        ieee80211_regdom[1]);
1898                 alpha2[0] = ieee80211_regdom[0];
1899                 alpha2[1] = ieee80211_regdom[1];
1900         } else
1901                 REG_DBG_PRINT("Restoring regulatory settings\n");
1902 }
1903
1904 static void restore_custom_reg_settings(struct wiphy *wiphy)
1905 {
1906         struct ieee80211_supported_band *sband;
1907         enum ieee80211_band band;
1908         struct ieee80211_channel *chan;
1909         int i;
1910
1911         for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
1912                 sband = wiphy->bands[band];
1913                 if (!sband)
1914                         continue;
1915                 for (i = 0; i < sband->n_channels; i++) {
1916                         chan = &sband->channels[i];
1917                         chan->flags = chan->orig_flags;
1918                         chan->max_antenna_gain = chan->orig_mag;
1919                         chan->max_power = chan->orig_mpwr;
1920                         chan->beacon_found = false;
1921                 }
1922         }
1923 }
1924
1925 /*
1926  * Restoring regulatory settings involves ingoring any
1927  * possibly stale country IE information and user regulatory
1928  * settings if so desired, this includes any beacon hints
1929  * learned as we could have traveled outside to another country
1930  * after disconnection. To restore regulatory settings we do
1931  * exactly what we did at bootup:
1932  *
1933  *   - send a core regulatory hint
1934  *   - send a user regulatory hint if applicable
1935  *
1936  * Device drivers that send a regulatory hint for a specific country
1937  * keep their own regulatory domain on wiphy->regd so that does does
1938  * not need to be remembered.
1939  */
1940 static void restore_regulatory_settings(bool reset_user)
1941 {
1942         char alpha2[2];
1943         char world_alpha2[2];
1944         struct reg_beacon *reg_beacon, *btmp;
1945         struct regulatory_request *reg_request, *tmp;
1946         LIST_HEAD(tmp_reg_req_list);
1947         struct cfg80211_registered_device *rdev;
1948
1949         mutex_lock(&cfg80211_mutex);
1950         mutex_lock(&reg_mutex);
1951
1952         reset_regdomains(true);
1953         restore_alpha2(alpha2, reset_user);
1954
1955         /*
1956          * If there's any pending requests we simply
1957          * stash them to a temporary pending queue and
1958          * add then after we've restored regulatory
1959          * settings.
1960          */
1961         spin_lock(&reg_requests_lock);
1962         if (!list_empty(&reg_requests_list)) {
1963                 list_for_each_entry_safe(reg_request, tmp,
1964                                          &reg_requests_list, list) {
1965                         if (reg_request->initiator !=
1966                             NL80211_REGDOM_SET_BY_USER)
1967                                 continue;
1968                         list_move_tail(&reg_request->list, &tmp_reg_req_list);
1969                 }
1970         }
1971         spin_unlock(&reg_requests_lock);
1972
1973         /* Clear beacon hints */
1974         spin_lock_bh(&reg_pending_beacons_lock);
1975         if (!list_empty(&reg_pending_beacons)) {
1976                 list_for_each_entry_safe(reg_beacon, btmp,
1977                                          &reg_pending_beacons, list) {
1978                         list_del(&reg_beacon->list);
1979                         kfree(reg_beacon);
1980                 }
1981         }
1982         spin_unlock_bh(&reg_pending_beacons_lock);
1983
1984         if (!list_empty(&reg_beacon_list)) {
1985                 list_for_each_entry_safe(reg_beacon, btmp,
1986                                          &reg_beacon_list, list) {
1987                         list_del(&reg_beacon->list);
1988                         kfree(reg_beacon);
1989                 }
1990         }
1991
1992         /* First restore to the basic regulatory settings */
1993         cfg80211_regdomain = cfg80211_world_regdom;
1994         world_alpha2[0] = cfg80211_regdomain->alpha2[0];
1995         world_alpha2[1] = cfg80211_regdomain->alpha2[1];
1996
1997         list_for_each_entry(rdev, &cfg80211_rdev_list, list) {
1998                 if (rdev->wiphy.flags & WIPHY_FLAG_CUSTOM_REGULATORY)
1999                         restore_custom_reg_settings(&rdev->wiphy);
2000         }
2001
2002         mutex_unlock(&reg_mutex);
2003         mutex_unlock(&cfg80211_mutex);
2004
2005         regulatory_hint_core(world_alpha2);
2006
2007         /*
2008          * This restores the ieee80211_regdom module parameter
2009          * preference or the last user requested regulatory
2010          * settings, user regulatory settings takes precedence.
2011          */
2012         if (is_an_alpha2(alpha2))
2013                 regulatory_hint_user(user_alpha2, NL80211_USER_REG_HINT_USER);
2014
2015         if (list_empty(&tmp_reg_req_list))
2016                 return;
2017
2018         mutex_lock(&cfg80211_mutex);
2019         mutex_lock(&reg_mutex);
2020
2021         spin_lock(&reg_requests_lock);
2022         list_for_each_entry_safe(reg_request, tmp, &tmp_reg_req_list, list) {
2023                 REG_DBG_PRINT("Adding request for country %c%c back "
2024                               "into the queue\n",
2025                               reg_request->alpha2[0],
2026                               reg_request->alpha2[1]);
2027                 list_move_tail(&reg_request->list, &reg_requests_list);
2028         }
2029         spin_unlock(&reg_requests_lock);
2030
2031         mutex_unlock(&reg_mutex);
2032         mutex_unlock(&cfg80211_mutex);
2033
2034         REG_DBG_PRINT("Kicking the queue\n");
2035
2036         schedule_work(&reg_work);
2037 }
2038
2039 void regulatory_hint_disconnect(void)
2040 {
2041         REG_DBG_PRINT("All devices are disconnected, going to "
2042                       "restore regulatory settings\n");
2043         restore_regulatory_settings(false);
2044 }
2045
2046 static bool freq_is_chan_12_13_14(u16 freq)
2047 {
2048         if (freq == ieee80211_channel_to_frequency(12, IEEE80211_BAND_2GHZ) ||
2049             freq == ieee80211_channel_to_frequency(13, IEEE80211_BAND_2GHZ) ||
2050             freq == ieee80211_channel_to_frequency(14, IEEE80211_BAND_2GHZ))
2051                 return true;
2052         return false;
2053 }
2054
2055 int regulatory_hint_found_beacon(struct wiphy *wiphy,
2056                                  struct ieee80211_channel *beacon_chan,
2057                                  gfp_t gfp)
2058 {
2059         struct reg_beacon *reg_beacon;
2060
2061         if (likely((beacon_chan->beacon_found ||
2062             (beacon_chan->flags & IEEE80211_CHAN_RADAR) ||
2063             (beacon_chan->band == IEEE80211_BAND_2GHZ &&
2064              !freq_is_chan_12_13_14(beacon_chan->center_freq)))))
2065                 return 0;
2066
2067         reg_beacon = kzalloc(sizeof(struct reg_beacon), gfp);
2068         if (!reg_beacon)
2069                 return -ENOMEM;
2070
2071         REG_DBG_PRINT("Found new beacon on "
2072                       "frequency: %d MHz (Ch %d) on %s\n",
2073                       beacon_chan->center_freq,
2074                       ieee80211_frequency_to_channel(beacon_chan->center_freq),
2075                       wiphy_name(wiphy));
2076
2077         memcpy(&reg_beacon->chan, beacon_chan,
2078                 sizeof(struct ieee80211_channel));
2079
2080
2081         /*
2082          * Since we can be called from BH or and non-BH context
2083          * we must use spin_lock_bh()
2084          */
2085         spin_lock_bh(&reg_pending_beacons_lock);
2086         list_add_tail(&reg_beacon->list, &reg_pending_beacons);
2087         spin_unlock_bh(&reg_pending_beacons_lock);
2088
2089         schedule_work(&reg_work);
2090
2091         return 0;
2092 }
2093
2094 static void print_rd_rules(const struct ieee80211_regdomain *rd)
2095 {
2096         unsigned int i;
2097         const struct ieee80211_reg_rule *reg_rule = NULL;
2098         const struct ieee80211_freq_range *freq_range = NULL;
2099         const struct ieee80211_power_rule *power_rule = NULL;
2100
2101         pr_info("  (start_freq - end_freq @ bandwidth), (max_antenna_gain, max_eirp)\n");
2102
2103         for (i = 0; i < rd->n_reg_rules; i++) {
2104                 reg_rule = &rd->reg_rules[i];
2105                 freq_range = &reg_rule->freq_range;
2106                 power_rule = &reg_rule->power_rule;
2107
2108                 /*
2109                  * There may not be documentation for max antenna gain
2110                  * in certain regions
2111                  */
2112                 if (power_rule->max_antenna_gain)
2113                         pr_info("  (%d KHz - %d KHz @ %d KHz), (%d mBi, %d mBm)\n",
2114                                 freq_range->start_freq_khz,
2115                                 freq_range->end_freq_khz,
2116                                 freq_range->max_bandwidth_khz,
2117                                 power_rule->max_antenna_gain,
2118                                 power_rule->max_eirp);
2119                 else
2120                         pr_info("  (%d KHz - %d KHz @ %d KHz), (N/A, %d mBm)\n",
2121                                 freq_range->start_freq_khz,
2122                                 freq_range->end_freq_khz,
2123                                 freq_range->max_bandwidth_khz,
2124                                 power_rule->max_eirp);
2125         }
2126 }
2127
2128 bool reg_supported_dfs_region(u8 dfs_region)
2129 {
2130         switch (dfs_region) {
2131         case NL80211_DFS_UNSET:
2132         case NL80211_DFS_FCC:
2133         case NL80211_DFS_ETSI:
2134         case NL80211_DFS_JP:
2135                 return true;
2136         default:
2137                 REG_DBG_PRINT("Ignoring uknown DFS master region: %d\n",
2138                               dfs_region);
2139                 return false;
2140         }
2141 }
2142
2143 static void print_dfs_region(u8 dfs_region)
2144 {
2145         if (!dfs_region)
2146                 return;
2147
2148         switch (dfs_region) {
2149         case NL80211_DFS_FCC:
2150                 pr_info(" DFS Master region FCC");
2151                 break;
2152         case NL80211_DFS_ETSI:
2153                 pr_info(" DFS Master region ETSI");
2154                 break;
2155         case NL80211_DFS_JP:
2156                 pr_info(" DFS Master region JP");
2157                 break;
2158         default:
2159                 pr_info(" DFS Master region Uknown");
2160                 break;
2161         }
2162 }
2163
2164 static void print_regdomain(const struct ieee80211_regdomain *rd)
2165 {
2166
2167         if (is_intersected_alpha2(rd->alpha2)) {
2168
2169                 if (last_request->initiator ==
2170                     NL80211_REGDOM_SET_BY_COUNTRY_IE) {
2171                         struct cfg80211_registered_device *rdev;
2172                         rdev = cfg80211_rdev_by_wiphy_idx(
2173                                 last_request->wiphy_idx);
2174                         if (rdev) {
2175                                 pr_info("Current regulatory domain updated by AP to: %c%c\n",
2176                                         rdev->country_ie_alpha2[0],
2177                                         rdev->country_ie_alpha2[1]);
2178                         } else
2179                                 pr_info("Current regulatory domain intersected:\n");
2180                 } else
2181                         pr_info("Current regulatory domain intersected:\n");
2182         } else if (is_world_regdom(rd->alpha2))
2183                 pr_info("World regulatory domain updated:\n");
2184         else {
2185                 if (is_unknown_alpha2(rd->alpha2))
2186                         pr_info("Regulatory domain changed to driver built-in settings (unknown country)\n");
2187                 else {
2188                         if (reg_request_cell_base(last_request))
2189                                 pr_info("Regulatory domain changed "
2190                                         "to country: %c%c by Cell Station\n",
2191                                         rd->alpha2[0], rd->alpha2[1]);
2192                         else
2193                                 pr_info("Regulatory domain changed "
2194                                         "to country: %c%c\n",
2195                                         rd->alpha2[0], rd->alpha2[1]);
2196                 }
2197         }
2198         print_dfs_region(rd->dfs_region);
2199         print_rd_rules(rd);
2200 }
2201
2202 static void print_regdomain_info(const struct ieee80211_regdomain *rd)
2203 {
2204         pr_info("Regulatory domain: %c%c\n", rd->alpha2[0], rd->alpha2[1]);
2205         print_rd_rules(rd);
2206 }
2207
2208 /* Takes ownership of rd only if it doesn't fail */
2209 static int __set_regdom(const struct ieee80211_regdomain *rd)
2210 {
2211         const struct ieee80211_regdomain *intersected_rd = NULL;
2212         struct wiphy *request_wiphy;
2213         /* Some basic sanity checks first */
2214
2215         if (is_world_regdom(rd->alpha2)) {
2216                 if (WARN_ON(!reg_is_valid_request(rd->alpha2)))
2217                         return -EINVAL;
2218                 update_world_regdomain(rd);
2219                 return 0;
2220         }
2221
2222         if (!is_alpha2_set(rd->alpha2) && !is_an_alpha2(rd->alpha2) &&
2223                         !is_unknown_alpha2(rd->alpha2))
2224                 return -EINVAL;
2225
2226         if (!last_request)
2227                 return -EINVAL;
2228
2229         /*
2230          * Lets only bother proceeding on the same alpha2 if the current
2231          * rd is non static (it means CRDA was present and was used last)
2232          * and the pending request came in from a country IE
2233          */
2234         if (last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE) {
2235                 /*
2236                  * If someone else asked us to change the rd lets only bother
2237                  * checking if the alpha2 changes if CRDA was already called
2238                  */
2239                 if (!regdom_changes(rd->alpha2))
2240                         return -EALREADY;
2241         }
2242
2243         /*
2244          * Now lets set the regulatory domain, update all driver channels
2245          * and finally inform them of what we have done, in case they want
2246          * to review or adjust their own settings based on their own
2247          * internal EEPROM data
2248          */
2249
2250         if (WARN_ON(!reg_is_valid_request(rd->alpha2)))
2251                 return -EINVAL;
2252
2253         if (!is_valid_rd(rd)) {
2254                 pr_err("Invalid regulatory domain detected:\n");
2255                 print_regdomain_info(rd);
2256                 return -EINVAL;
2257         }
2258
2259         request_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);
2260         if (!request_wiphy &&
2261             (last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER ||
2262              last_request->initiator == NL80211_REGDOM_SET_BY_COUNTRY_IE)) {
2263                 schedule_delayed_work(&reg_timeout, 0);
2264                 return -ENODEV;
2265         }
2266
2267         if (!last_request->intersect) {
2268                 int r;
2269
2270                 if (last_request->initiator != NL80211_REGDOM_SET_BY_DRIVER) {
2271                         reset_regdomains(false);
2272                         cfg80211_regdomain = rd;
2273                         return 0;
2274                 }
2275
2276                 /*
2277                  * For a driver hint, lets copy the regulatory domain the
2278                  * driver wanted to the wiphy to deal with conflicts
2279                  */
2280
2281                 /*
2282                  * Userspace could have sent two replies with only
2283                  * one kernel request.
2284                  */
2285                 if (request_wiphy->regd)
2286                         return -EALREADY;
2287
2288                 r = reg_copy_regd(&request_wiphy->regd, rd);
2289                 if (r)
2290                         return r;
2291
2292                 reset_regdomains(false);
2293                 cfg80211_regdomain = rd;
2294                 return 0;
2295         }
2296
2297         /* Intersection requires a bit more work */
2298
2299         if (last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE) {
2300
2301                 intersected_rd = regdom_intersect(rd, cfg80211_regdomain);
2302                 if (!intersected_rd)
2303                         return -EINVAL;
2304
2305                 /*
2306                  * We can trash what CRDA provided now.
2307                  * However if a driver requested this specific regulatory
2308                  * domain we keep it for its private use
2309                  */
2310                 if (last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER)
2311                         request_wiphy->regd = rd;
2312                 else
2313                         kfree(rd);
2314
2315                 rd = NULL;
2316
2317                 reset_regdomains(false);
2318                 cfg80211_regdomain = intersected_rd;
2319
2320                 return 0;
2321         }
2322
2323         return -EINVAL;
2324 }
2325
2326
2327 /*
2328  * Use this call to set the current regulatory domain. Conflicts with
2329  * multiple drivers can be ironed out later. Caller must've already
2330  * kmalloc'd the rd structure. Caller must hold cfg80211_mutex
2331  */
2332 int set_regdom(const struct ieee80211_regdomain *rd)
2333 {
2334         int r;
2335
2336         assert_cfg80211_lock();
2337
2338         mutex_lock(&reg_mutex);
2339
2340         /* Note that this doesn't update the wiphys, this is done below */
2341         r = __set_regdom(rd);
2342         if (r) {
2343                 if (r == -EALREADY)
2344                         reg_set_request_processed();
2345
2346                 kfree(rd);
2347                 mutex_unlock(&reg_mutex);
2348                 return r;
2349         }
2350
2351         /* This would make this whole thing pointless */
2352         if (!last_request->intersect)
2353                 BUG_ON(rd != cfg80211_regdomain);
2354
2355         /* update all wiphys now with the new established regulatory domain */
2356         update_all_wiphy_regulatory(last_request->initiator);
2357
2358         print_regdomain(cfg80211_regdomain);
2359
2360         nl80211_send_reg_change_event(last_request);
2361
2362         reg_set_request_processed();
2363
2364         mutex_unlock(&reg_mutex);
2365
2366         return r;
2367 }
2368
2369 #ifdef CONFIG_HOTPLUG
2370 int reg_device_uevent(struct device *dev, struct kobj_uevent_env *env)
2371 {
2372         if (last_request && !last_request->processed) {
2373                 if (add_uevent_var(env, "COUNTRY=%c%c",
2374                                    last_request->alpha2[0],
2375                                    last_request->alpha2[1]))
2376                         return -ENOMEM;
2377         }
2378
2379         return 0;
2380 }
2381 #else
2382 int reg_device_uevent(struct device *dev, struct kobj_uevent_env *env)
2383 {
2384         return -ENODEV;
2385 }
2386 #endif /* CONFIG_HOTPLUG */
2387
2388 void wiphy_regulatory_register(struct wiphy *wiphy)
2389 {
2390         assert_cfg80211_lock();
2391
2392         mutex_lock(&reg_mutex);
2393
2394         if (!reg_dev_ignore_cell_hint(wiphy))
2395                 reg_num_devs_support_basehint++;
2396
2397         wiphy_update_regulatory(wiphy, NL80211_REGDOM_SET_BY_CORE);
2398
2399         mutex_unlock(&reg_mutex);
2400 }
2401
2402 /* Caller must hold cfg80211_mutex */
2403 void wiphy_regulatory_deregister(struct wiphy *wiphy)
2404 {
2405         struct wiphy *request_wiphy = NULL;
2406
2407         assert_cfg80211_lock();
2408
2409         mutex_lock(&reg_mutex);
2410
2411         if (!reg_dev_ignore_cell_hint(wiphy))
2412                 reg_num_devs_support_basehint--;
2413
2414         kfree(wiphy->regd);
2415
2416         if (last_request)
2417                 request_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);
2418
2419         if (!request_wiphy || request_wiphy != wiphy)
2420                 goto out;
2421
2422         last_request->wiphy_idx = WIPHY_IDX_STALE;
2423         last_request->country_ie_env = ENVIRON_ANY;
2424 out:
2425         mutex_unlock(&reg_mutex);
2426 }
2427
2428 static void reg_timeout_work(struct work_struct *work)
2429 {
2430         REG_DBG_PRINT("Timeout while waiting for CRDA to reply, "
2431                       "restoring regulatory settings\n");
2432         restore_regulatory_settings(true);
2433 }
2434
2435 int __init regulatory_init(void)
2436 {
2437         int err = 0;
2438
2439         reg_pdev = platform_device_register_simple("regulatory", 0, NULL, 0);
2440         if (IS_ERR(reg_pdev))
2441                 return PTR_ERR(reg_pdev);
2442
2443         reg_pdev->dev.type = &reg_device_type;
2444
2445         spin_lock_init(&reg_requests_lock);
2446         spin_lock_init(&reg_pending_beacons_lock);
2447
2448         reg_regdb_size_check();
2449
2450         cfg80211_regdomain = cfg80211_world_regdom;
2451
2452         user_alpha2[0] = '9';
2453         user_alpha2[1] = '7';
2454
2455         /* We always try to get an update for the static regdomain */
2456         err = regulatory_hint_core(cfg80211_regdomain->alpha2);
2457         if (err) {
2458                 if (err == -ENOMEM)
2459                         return err;
2460                 /*
2461                  * N.B. kobject_uevent_env() can fail mainly for when we're out
2462                  * memory which is handled and propagated appropriately above
2463                  * but it can also fail during a netlink_broadcast() or during
2464                  * early boot for call_usermodehelper(). For now treat these
2465                  * errors as non-fatal.
2466                  */
2467                 pr_err("kobject_uevent_env() was unable to call CRDA during init\n");
2468 #ifdef CONFIG_CFG80211_REG_DEBUG
2469                 /* We want to find out exactly why when debugging */
2470                 WARN_ON(err);
2471 #endif
2472         }
2473
2474         /*
2475          * Finally, if the user set the module parameter treat it
2476          * as a user hint.
2477          */
2478         if (!is_world_regdom(ieee80211_regdom))
2479                 regulatory_hint_user(ieee80211_regdom,
2480                                      NL80211_USER_REG_HINT_USER);
2481
2482         return 0;
2483 }
2484
2485 void /* __init_or_exit */ regulatory_exit(void)
2486 {
2487         struct regulatory_request *reg_request, *tmp;
2488         struct reg_beacon *reg_beacon, *btmp;
2489
2490         cancel_work_sync(&reg_work);
2491         cancel_delayed_work_sync(&reg_timeout);
2492
2493         mutex_lock(&cfg80211_mutex);
2494         mutex_lock(&reg_mutex);
2495
2496         reset_regdomains(true);
2497
2498         dev_set_uevent_suppress(&reg_pdev->dev, true);
2499
2500         platform_device_unregister(reg_pdev);
2501
2502         spin_lock_bh(&reg_pending_beacons_lock);
2503         if (!list_empty(&reg_pending_beacons)) {
2504                 list_for_each_entry_safe(reg_beacon, btmp,
2505                                          &reg_pending_beacons, list) {
2506                         list_del(&reg_beacon->list);
2507                         kfree(reg_beacon);
2508                 }
2509         }
2510         spin_unlock_bh(&reg_pending_beacons_lock);
2511
2512         if (!list_empty(&reg_beacon_list)) {
2513                 list_for_each_entry_safe(reg_beacon, btmp,
2514                                          &reg_beacon_list, list) {
2515                         list_del(&reg_beacon->list);
2516                         kfree(reg_beacon);
2517                 }
2518         }
2519
2520         spin_lock(&reg_requests_lock);
2521         if (!list_empty(&reg_requests_list)) {
2522                 list_for_each_entry_safe(reg_request, tmp,
2523                                          &reg_requests_list, list) {
2524                         list_del(&reg_request->list);
2525                         kfree(reg_request);
2526                 }
2527         }
2528         spin_unlock(&reg_requests_lock);
2529
2530         mutex_unlock(&reg_mutex);
2531         mutex_unlock(&cfg80211_mutex);
2532 }