git.oblomov.eu Git - linux-2.6/blob - net/wireless/reg.c

   1 /*
   2  * Copyright 2002-2005, Instant802 Networks, Inc.
   3  * Copyright 2005-2006, Devicescape Software, Inc.
   4  * Copyright 2007       Johannes Berg <johannes@sipsolutions.net>
   5  * Copyright 2008       Luis R. Rodriguez <lrodriguz@atheros.com>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  */
  11
  12 /**
  13  * DOC: Wireless regulatory infrastructure
  14  *
  15  * The usual implementation is for a driver to read a device EEPROM to
  16  * determine which regulatory domain it should be operating under, then
  17  * looking up the allowable channels in a driver-local table and finally
  18  * registering those channels in the wiphy structure.
  19  *
  20  * Another set of compliance enforcement is for drivers to use their
  21  * own compliance limits which can be stored on the EEPROM. The host
  22  * driver or firmware may ensure these are used.
  23  *
  24  * In addition to all this we provide an extra layer of regulatory
  25  * conformance. For drivers which do not have any regulatory
  26  * information CRDA provides the complete regulatory solution.
  27  * For others it provides a community effort on further restrictions
  28  * to enhance compliance.
  29  *
  30  * Note: When number of rules --> infinity we will not be able to
  31  * index on alpha2 any more, instead we'll probably have to
  32  * rely on some SHA1 checksum of the regdomain for example.
  33  *
  34  */
  35 #include <linux/kernel.h>
  36 #include <linux/list.h>
  37 #include <linux/random.h>
  38 #include <linux/nl80211.h>
  39 #include <linux/platform_device.h>
  40 #include <net/cfg80211.h>
  41 #include "core.h"
  42 #include "reg.h"
  43 #include "nl80211.h"
  44
  45 /* Receipt of information from last regulatory request */
  46 static struct regulatory_request *last_request;
  47
  48 /* To trigger userspace events */
  49 static struct platform_device *reg_pdev;
  50
  51 /* Keep the ordering from large to small */
  52 static u32 supported_bandwidths[] = {
  53         MHZ_TO_KHZ(40),
  54         MHZ_TO_KHZ(20),
  55 };
  56
  57 /*
  58  * Central wireless core regulatory domains, we only need two,
  59  * the current one and a world regulatory domain in case we have no
  60  * information to give us an alpha2
  61  */
  62 const struct ieee80211_regdomain *cfg80211_regdomain;
  63
  64 /*
  65  * We use this as a place for the rd structure built from the
  66  * last parsed country IE to rest until CRDA gets back to us with
  67  * what it thinks should apply for the same country
  68  */
  69 static const struct ieee80211_regdomain *country_ie_regdomain;
  70
  71 /* Used to queue up regulatory hints */
  72 static LIST_HEAD(reg_requests_list);
  73 static spinlock_t reg_requests_lock;
  74
  75 /* Used to queue up beacon hints for review */
  76 static LIST_HEAD(reg_pending_beacons);
  77 static spinlock_t reg_pending_beacons_lock;
  78
  79 /* Used to keep track of processed beacon hints */
  80 static LIST_HEAD(reg_beacon_list);
  81
  82 struct reg_beacon {
  83         struct list_head list;
  84         struct ieee80211_channel chan;
  85 };
  86
  87 /* We keep a static world regulatory domain in case of the absence of CRDA */
  88 static const struct ieee80211_regdomain world_regdom = {
  89         .n_reg_rules = 5,
  90         .alpha2 =  "00",
  91         .reg_rules = {
  92                 /* IEEE 802.11b/g, channels 1..11 */
  93                 REG_RULE(2412-10, 2462+10, 40, 6, 20, 0),
  94                 /* IEEE 802.11b/g, channels 12..13. No HT40
  95                  * channel fits here. */
  96                 REG_RULE(2467-10, 2472+10, 20, 6, 20,
  97                         NL80211_RRF_PASSIVE_SCAN |
  98                         NL80211_RRF_NO_IBSS),
  99                 /* IEEE 802.11 channel 14 - Only JP enables
 100                  * this and for 802.11b only */
 101                 REG_RULE(2484-10, 2484+10, 20, 6, 20,
 102                         NL80211_RRF_PASSIVE_SCAN |
 103                         NL80211_RRF_NO_IBSS |
 104                         NL80211_RRF_NO_OFDM),
 105                 /* IEEE 802.11a, channel 36..48 */
 106                 REG_RULE(5180-10, 5240+10, 40, 6, 20,
 107                         NL80211_RRF_PASSIVE_SCAN |
 108                         NL80211_RRF_NO_IBSS),
 109
 110                 /* NB: 5260 MHz - 5700 MHz requies DFS */
 111
 112                 /* IEEE 802.11a, channel 149..165 */
 113                 REG_RULE(5745-10, 5825+10, 40, 6, 20,
 114                         NL80211_RRF_PASSIVE_SCAN |
 115                         NL80211_RRF_NO_IBSS),
 116         }
 117 };
 118
 119 static const struct ieee80211_regdomain *cfg80211_world_regdom =
 120         &world_regdom;
 121
 122 #ifdef CONFIG_WIRELESS_OLD_REGULATORY
 123 static char *ieee80211_regdom = "US";
 124 #else
 125 static char *ieee80211_regdom = "00";
 126 #endif
 127
 128 module_param(ieee80211_regdom, charp, 0444);
 129 MODULE_PARM_DESC(ieee80211_regdom, "IEEE 802.11 regulatory domain code");
 130
 131 #ifdef CONFIG_WIRELESS_OLD_REGULATORY
 132 /*
 133  * We assume 40 MHz bandwidth for the old regulatory work.
 134  * We make emphasis we are using the exact same frequencies
 135  * as before
 136  */
 137
 138 static const struct ieee80211_regdomain us_regdom = {
 139         .n_reg_rules = 6,
 140         .alpha2 =  "US",
 141         .reg_rules = {
 142                 /* IEEE 802.11b/g, channels 1..11 */
 143                 REG_RULE(2412-10, 2462+10, 40, 6, 27, 0),
 144                 /* IEEE 802.11a, channel 36 */
 145                 REG_RULE(5180-10, 5180+10, 40, 6, 23, 0),
 146                 /* IEEE 802.11a, channel 40 */
 147                 REG_RULE(5200-10, 5200+10, 40, 6, 23, 0),
 148                 /* IEEE 802.11a, channel 44 */
 149                 REG_RULE(5220-10, 5220+10, 40, 6, 23, 0),
 150                 /* IEEE 802.11a, channels 48..64 */
 151                 REG_RULE(5240-10, 5320+10, 40, 6, 23, 0),
 152                 /* IEEE 802.11a, channels 149..165, outdoor */
 153                 REG_RULE(5745-10, 5825+10, 40, 6, 30, 0),
 154         }
 155 };
 156
 157 static const struct ieee80211_regdomain jp_regdom = {
 158         .n_reg_rules = 3,
 159         .alpha2 =  "JP",
 160         .reg_rules = {
 161                 /* IEEE 802.11b/g, channels 1..14 */
 162                 REG_RULE(2412-10, 2484+10, 40, 6, 20, 0),
 163                 /* IEEE 802.11a, channels 34..48 */
 164                 REG_RULE(5170-10, 5240+10, 40, 6, 20,
 165                         NL80211_RRF_PASSIVE_SCAN),
 166                 /* IEEE 802.11a, channels 52..64 */
 167                 REG_RULE(5260-10, 5320+10, 40, 6, 20,
 168                         NL80211_RRF_NO_IBSS |
 169                         NL80211_RRF_DFS),
 170         }
 171 };
 172
 173 static const struct ieee80211_regdomain eu_regdom = {
 174         .n_reg_rules = 6,
 175         /*
 176          * This alpha2 is bogus, we leave it here just for stupid
 177          * backward compatibility
 178          */
 179         .alpha2 =  "EU",
 180         .reg_rules = {
 181                 /* IEEE 802.11b/g, channels 1..13 */
 182                 REG_RULE(2412-10, 2472+10, 40, 6, 20, 0),
 183                 /* IEEE 802.11a, channel 36 */
 184                 REG_RULE(5180-10, 5180+10, 40, 6, 23,
 185                         NL80211_RRF_PASSIVE_SCAN),
 186                 /* IEEE 802.11a, channel 40 */
 187                 REG_RULE(5200-10, 5200+10, 40, 6, 23,
 188                         NL80211_RRF_PASSIVE_SCAN),
 189                 /* IEEE 802.11a, channel 44 */
 190                 REG_RULE(5220-10, 5220+10, 40, 6, 23,
 191                         NL80211_RRF_PASSIVE_SCAN),
 192                 /* IEEE 802.11a, channels 48..64 */
 193                 REG_RULE(5240-10, 5320+10, 40, 6, 20,
 194                         NL80211_RRF_NO_IBSS |
 195                         NL80211_RRF_DFS),
 196                 /* IEEE 802.11a, channels 100..140 */
 197                 REG_RULE(5500-10, 5700+10, 40, 6, 30,
 198                         NL80211_RRF_NO_IBSS |
 199                         NL80211_RRF_DFS),
 200         }
 201 };
 202
 203 static const struct ieee80211_regdomain *static_regdom(char *alpha2)
 204 {
 205         if (alpha2[0] == 'U' && alpha2[1] == 'S')
 206                 return &us_regdom;
 207         if (alpha2[0] == 'J' && alpha2[1] == 'P')
 208                 return &jp_regdom;
 209         if (alpha2[0] == 'E' && alpha2[1] == 'U')
 210                 return &eu_regdom;
 211         /* Default, as per the old rules */
 212         return &us_regdom;
 213 }
 214
 215 static bool is_old_static_regdom(const struct ieee80211_regdomain *rd)
 216 {
 217         if (rd == &us_regdom || rd == &jp_regdom || rd == &eu_regdom)
 218                 return true;
 219         return false;
 220 }
 221 #else
 222 static inline bool is_old_static_regdom(const struct ieee80211_regdomain *rd)
 223 {
 224         return false;
 225 }
 226 #endif
 227
 228 static void reset_regdomains(void)
 229 {
 230         /* avoid freeing static information or freeing something twice */
 231         if (cfg80211_regdomain == cfg80211_world_regdom)
 232                 cfg80211_regdomain = NULL;
 233         if (cfg80211_world_regdom == &world_regdom)
 234                 cfg80211_world_regdom = NULL;
 235         if (cfg80211_regdomain == &world_regdom)
 236                 cfg80211_regdomain = NULL;
 237         if (is_old_static_regdom(cfg80211_regdomain))
 238                 cfg80211_regdomain = NULL;
 239
 240         kfree(cfg80211_regdomain);
 241         kfree(cfg80211_world_regdom);
 242
 243         cfg80211_world_regdom = &world_regdom;
 244         cfg80211_regdomain = NULL;
 245 }
 246
 247 /*
 248  * Dynamic world regulatory domain requested by the wireless
 249  * core upon initialization
 250  */
 251 static void update_world_regdomain(const struct ieee80211_regdomain *rd)
 252 {
 253         BUG_ON(!last_request);
 254
 255         reset_regdomains();
 256
 257         cfg80211_world_regdom = rd;
 258         cfg80211_regdomain = rd;
 259 }
 260
 261 bool is_world_regdom(const char *alpha2)
 262 {
 263         if (!alpha2)
 264                 return false;
 265         if (alpha2[0] == '0' && alpha2[1] == '0')
 266                 return true;
 267         return false;
 268 }
 269
 270 static bool is_alpha2_set(const char *alpha2)
 271 {
 272         if (!alpha2)
 273                 return false;
 274         if (alpha2[0] != 0 && alpha2[1] != 0)
 275                 return true;
 276         return false;
 277 }
 278
 279 static bool is_alpha_upper(char letter)
 280 {
 281         /* ASCII A - Z */
 282         if (letter >= 65 && letter <= 90)
 283                 return true;
 284         return false;
 285 }
 286
 287 static bool is_unknown_alpha2(const char *alpha2)
 288 {
 289         if (!alpha2)
 290                 return false;
 291         /*
 292          * Special case where regulatory domain was built by driver
 293          * but a specific alpha2 cannot be determined
 294          */
 295         if (alpha2[0] == '9' && alpha2[1] == '9')
 296                 return true;
 297         return false;
 298 }
 299
 300 static bool is_intersected_alpha2(const char *alpha2)
 301 {
 302         if (!alpha2)
 303                 return false;
 304         /*
 305          * Special case where regulatory domain is the
 306          * result of an intersection between two regulatory domain
 307          * structures
 308          */
 309         if (alpha2[0] == '9' && alpha2[1] == '8')
 310                 return true;
 311         return false;
 312 }
 313
 314 static bool is_an_alpha2(const char *alpha2)
 315 {
 316         if (!alpha2)
 317                 return false;
 318         if (is_alpha_upper(alpha2[0]) && is_alpha_upper(alpha2[1]))
 319                 return true;
 320         return false;
 321 }
 322
 323 static bool alpha2_equal(const char *alpha2_x, const char *alpha2_y)
 324 {
 325         if (!alpha2_x || !alpha2_y)
 326                 return false;
 327         if (alpha2_x[0] == alpha2_y[0] &&
 328                 alpha2_x[1] == alpha2_y[1])
 329                 return true;
 330         return false;
 331 }
 332
 333 static bool regdom_changes(const char *alpha2)
 334 {
 335         assert_cfg80211_lock();
 336
 337         if (!cfg80211_regdomain)
 338                 return true;
 339         if (alpha2_equal(cfg80211_regdomain->alpha2, alpha2))
 340                 return false;
 341         return true;
 342 }
 343
 344 /**
 345  * country_ie_integrity_changes - tells us if the country IE has changed
 346  * @checksum: checksum of country IE of fields we are interested in
 347  *
 348  * If the country IE has not changed you can ignore it safely. This is
 349  * useful to determine if two devices are seeing two different country IEs
 350  * even on the same alpha2. Note that this will return false if no IE has
 351  * been set on the wireless core yet.
 352  */
 353 static bool country_ie_integrity_changes(u32 checksum)
 354 {
 355         /* If no IE has been set then the checksum doesn't change */
 356         if (unlikely(!last_request->country_ie_checksum))
 357                 return false;
 358         if (unlikely(last_request->country_ie_checksum != checksum))
 359                 return true;
 360         return false;
 361 }
 362
 363 /*
 364  * This lets us keep regulatory code which is updated on a regulatory
 365  * basis in userspace.
 366  */
 367 static int call_crda(const char *alpha2)
 368 {
 369         char country_env[9 + 2] = "COUNTRY=";
 370         char *envp[] = {
 371                 country_env,
 372                 NULL
 373         };
 374
 375         if (!is_world_regdom((char *) alpha2))
 376                 printk(KERN_INFO "cfg80211: Calling CRDA for country: %c%c\n",
 377                         alpha2[0], alpha2[1]);
 378         else
 379                 printk(KERN_INFO "cfg80211: Calling CRDA to update world "
 380                         "regulatory domain\n");
 381
 382         country_env[8] = alpha2[0];
 383         country_env[9] = alpha2[1];
 384
 385         return kobject_uevent_env(&reg_pdev->dev.kobj, KOBJ_CHANGE, envp);
 386 }
 387
 388 /* Used by nl80211 before kmalloc'ing our regulatory domain */
 389 bool reg_is_valid_request(const char *alpha2)
 390 {
 391         if (!last_request)
 392                 return false;
 393
 394         return alpha2_equal(last_request->alpha2, alpha2);
 395 }
 396
 397 /* Sanity check on a regulatory rule */
 398 static bool is_valid_reg_rule(const struct ieee80211_reg_rule *rule)
 399 {
 400         const struct ieee80211_freq_range *freq_range = &rule->freq_range;
 401         u32 freq_diff;
 402
 403         if (freq_range->start_freq_khz <= 0 || freq_range->end_freq_khz <= 0)
 404                 return false;
 405
 406         if (freq_range->start_freq_khz > freq_range->end_freq_khz)
 407                 return false;
 408
 409         freq_diff = freq_range->end_freq_khz - freq_range->start_freq_khz;
 410
 411         if (freq_range->end_freq_khz <= freq_range->start_freq_khz ||
 412                         freq_range->max_bandwidth_khz > freq_diff)
 413                 return false;
 414
 415         return true;
 416 }
 417
 418 static bool is_valid_rd(const struct ieee80211_regdomain *rd)
 419 {
 420         const struct ieee80211_reg_rule *reg_rule = NULL;
 421         unsigned int i;
 422
 423         if (!rd->n_reg_rules)
 424                 return false;
 425
 426         if (WARN_ON(rd->n_reg_rules > NL80211_MAX_SUPP_REG_RULES))
 427                 return false;
 428
 429         for (i = 0; i < rd->n_reg_rules; i++) {
 430                 reg_rule = &rd->reg_rules[i];
 431                 if (!is_valid_reg_rule(reg_rule))
 432                         return false;
 433         }
 434
 435         return true;
 436 }
 437
 438 /* Returns value in KHz */
 439 static u32 freq_max_bandwidth(const struct ieee80211_freq_range *freq_range,
 440         u32 freq)
 441 {
 442         unsigned int i;
 443         for (i = 0; i < ARRAY_SIZE(supported_bandwidths); i++) {
 444                 u32 start_freq_khz = freq - supported_bandwidths[i]/2;
 445                 u32 end_freq_khz = freq + supported_bandwidths[i]/2;
 446                 if (start_freq_khz >= freq_range->start_freq_khz &&
 447                         end_freq_khz <= freq_range->end_freq_khz)
 448                         return supported_bandwidths[i];
 449         }
 450         return 0;
 451 }
 452
 453 /**
 454  * freq_in_rule_band - tells us if a frequency is in a frequency band
 455  * @freq_range: frequency rule we want to query
 456  * @freq_khz: frequency we are inquiring about
 457  *
 458  * This lets us know if a specific frequency rule is or is not relevant to
 459  * a specific frequency's band. Bands are device specific and artificial
 460  * definitions (the "2.4 GHz band" and the "5 GHz band"), however it is
 461  * safe for now to assume that a frequency rule should not be part of a
 462  * frequency's band if the start freq or end freq are off by more than 2 GHz.
 463  * This resolution can be lowered and should be considered as we add
 464  * regulatory rule support for other "bands".
 465  **/
 466 static bool freq_in_rule_band(const struct ieee80211_freq_range *freq_range,
 467         u32 freq_khz)
 468 {
 469 #define ONE_GHZ_IN_KHZ  1000000
 470         if (abs(freq_khz - freq_range->start_freq_khz) <= (2 * ONE_GHZ_IN_KHZ))
 471                 return true;
 472         if (abs(freq_khz - freq_range->end_freq_khz) <= (2 * ONE_GHZ_IN_KHZ))
 473                 return true;
 474         return false;
 475 #undef ONE_GHZ_IN_KHZ
 476 }
 477
 478 /*
 479  * Converts a country IE to a regulatory domain. A regulatory domain
 480  * structure has a lot of information which the IE doesn't yet have,
 481  * so for the other values we use upper max values as we will intersect
 482  * with our userspace regulatory agent to get lower bounds.
 483  */
 484 static struct ieee80211_regdomain *country_ie_2_rd(
 485                                 u8 *country_ie,
 486                                 u8 country_ie_len,
 487                                 u32 *checksum)
 488 {
 489         struct ieee80211_regdomain *rd = NULL;
 490         unsigned int i = 0;
 491         char alpha2[2];
 492         u32 flags = 0;
 493         u32 num_rules = 0, size_of_regd = 0;
 494         u8 *triplets_start = NULL;
 495         u8 len_at_triplet = 0;
 496         /* the last channel we have registered in a subband (triplet) */
 497         int last_sub_max_channel = 0;
 498
 499         *checksum = 0xDEADBEEF;
 500
 501         /* Country IE requirements */
 502         BUG_ON(country_ie_len < IEEE80211_COUNTRY_IE_MIN_LEN ||
 503                 country_ie_len & 0x01);
 504
 505         alpha2[0] = country_ie[0];
 506         alpha2[1] = country_ie[1];
 507
 508         /*
 509          * Third octet can be:
 510          *    'I' - Indoor
 511          *    'O' - Outdoor
 512          *
 513          *  anything else we assume is no restrictions
 514          */
 515         if (country_ie[2] == 'I')
 516                 flags = NL80211_RRF_NO_OUTDOOR;
 517         else if (country_ie[2] == 'O')
 518                 flags = NL80211_RRF_NO_INDOOR;
 519
 520         country_ie += 3;
 521         country_ie_len -= 3;
 522
 523         triplets_start = country_ie;
 524         len_at_triplet = country_ie_len;
 525
 526         *checksum ^= ((flags ^ alpha2[0] ^ alpha2[1]) << 8);
 527
 528         /*
 529          * We need to build a reg rule for each triplet, but first we must
 530          * calculate the number of reg rules we will need. We will need one
 531          * for each channel subband
 532          */
 533         while (country_ie_len >= 3) {
 534                 int end_channel = 0;
 535                 struct ieee80211_country_ie_triplet *triplet =
 536                         (struct ieee80211_country_ie_triplet *) country_ie;
 537                 int cur_sub_max_channel = 0, cur_channel = 0;
 538
 539                 if (triplet->ext.reg_extension_id >=
 540                                 IEEE80211_COUNTRY_EXTENSION_ID) {
 541                         country_ie += 3;
 542                         country_ie_len -= 3;
 543                         continue;
 544                 }
 545
 546                 /* 2 GHz */
 547                 if (triplet->chans.first_channel <= 14)
 548                         end_channel = triplet->chans.first_channel +
 549                                 triplet->chans.num_channels;
 550                 else
 551                         /*
 552                          * 5 GHz -- For example in country IEs if the first
 553                          * channel given is 36 and the number of channels is 4
 554                          * then the individual channel numbers defined for the
 555                          * 5 GHz PHY by these parameters are: 36, 40, 44, and 48
 556                          * and not 36, 37, 38, 39.
 557                          *
 558                          * See: http://tinyurl.com/11d-clarification
 559                          */
 560                         end_channel =  triplet->chans.first_channel +
 561                                 (4 * (triplet->chans.num_channels - 1));
 562
 563                 cur_channel = triplet->chans.first_channel;
 564                 cur_sub_max_channel = end_channel;
 565
 566                 /* Basic sanity check */
 567                 if (cur_sub_max_channel < cur_channel)
 568                         return NULL;
 569
 570                 /*
 571                  * Do not allow overlapping channels. Also channels
 572                  * passed in each subband must be monotonically
 573                  * increasing
 574                  */
 575                 if (last_sub_max_channel) {
 576                         if (cur_channel <= last_sub_max_channel)
 577                                 return NULL;
 578                         if (cur_sub_max_channel <= last_sub_max_channel)
 579                                 return NULL;
 580                 }
 581
 582                 /*
 583                  * When dot11RegulatoryClassesRequired is supported
 584                  * we can throw ext triplets as part of this soup,
 585                  * for now we don't care when those change as we
 586                  * don't support them
 587                  */
 588                 *checksum ^= ((cur_channel ^ cur_sub_max_channel) << 8) |
 589                   ((cur_sub_max_channel ^ cur_sub_max_channel) << 16) |
 590                   ((triplet->chans.max_power ^ cur_sub_max_channel) << 24);
 591
 592                 last_sub_max_channel = cur_sub_max_channel;
 593
 594                 country_ie += 3;
 595                 country_ie_len -= 3;
 596                 num_rules++;
 597
 598                 /*
 599                  * Note: this is not a IEEE requirement but
 600                  * simply a memory requirement
 601                  */
 602                 if (num_rules > NL80211_MAX_SUPP_REG_RULES)
 603                         return NULL;
 604         }
 605
 606         country_ie = triplets_start;
 607         country_ie_len = len_at_triplet;
 608
 609         size_of_regd = sizeof(struct ieee80211_regdomain) +
 610                 (num_rules * sizeof(struct ieee80211_reg_rule));
 611
 612         rd = kzalloc(size_of_regd, GFP_KERNEL);
 613         if (!rd)
 614                 return NULL;
 615
 616         rd->n_reg_rules = num_rules;
 617         rd->alpha2[0] = alpha2[0];
 618         rd->alpha2[1] = alpha2[1];
 619
 620         /* This time around we fill in the rd */
 621         while (country_ie_len >= 3) {
 622                 int end_channel = 0;
 623                 struct ieee80211_country_ie_triplet *triplet =
 624                         (struct ieee80211_country_ie_triplet *) country_ie;
 625                 struct ieee80211_reg_rule *reg_rule = NULL;
 626                 struct ieee80211_freq_range *freq_range = NULL;
 627                 struct ieee80211_power_rule *power_rule = NULL;
 628
 629                 /*
 630                  * Must parse if dot11RegulatoryClassesRequired is true,
 631                  * we don't support this yet
 632                  */
 633                 if (triplet->ext.reg_extension_id >=
 634                                 IEEE80211_COUNTRY_EXTENSION_ID) {
 635                         country_ie += 3;
 636                         country_ie_len -= 3;
 637                         continue;
 638                 }
 639
 640                 reg_rule = &rd->reg_rules[i];
 641                 freq_range = &reg_rule->freq_range;
 642                 power_rule = &reg_rule->power_rule;
 643
 644                 reg_rule->flags = flags;
 645
 646                 /* 2 GHz */
 647                 if (triplet->chans.first_channel <= 14)
 648                         end_channel = triplet->chans.first_channel +
 649                                 triplet->chans.num_channels;
 650                 else
 651                         end_channel =  triplet->chans.first_channel +
 652                                 (4 * (triplet->chans.num_channels - 1));
 653
 654                 /*
 655                  * The +10 is since the regulatory domain expects
 656                  * the actual band edge, not the center of freq for
 657                  * its start and end freqs, assuming 20 MHz bandwidth on
 658                  * the channels passed
 659                  */
 660                 freq_range->start_freq_khz =
 661                         MHZ_TO_KHZ(ieee80211_channel_to_frequency(
 662                                 triplet->chans.first_channel) - 10);
 663                 freq_range->end_freq_khz =
 664                         MHZ_TO_KHZ(ieee80211_channel_to_frequency(
 665                                 end_channel) + 10);
 666
 667                 /*
 668                  * These are large arbitrary values we use to intersect later.
 669                  * Increment this if we ever support >= 40 MHz channels
 670                  * in IEEE 802.11
 671                  */
 672                 freq_range->max_bandwidth_khz = MHZ_TO_KHZ(40);
 673                 power_rule->max_antenna_gain = DBI_TO_MBI(100);
 674                 power_rule->max_eirp = DBM_TO_MBM(100);
 675
 676                 country_ie += 3;
 677                 country_ie_len -= 3;
 678                 i++;
 679
 680                 BUG_ON(i > NL80211_MAX_SUPP_REG_RULES);
 681         }
 682
 683         return rd;
 684 }
 685
 686
 687 /*
 688  * Helper for regdom_intersect(), this does the real
 689  * mathematical intersection fun
 690  */
 691 static int reg_rules_intersect(
 692         const struct ieee80211_reg_rule *rule1,
 693         const struct ieee80211_reg_rule *rule2,
 694         struct ieee80211_reg_rule *intersected_rule)
 695 {
 696         const struct ieee80211_freq_range *freq_range1, *freq_range2;
 697         struct ieee80211_freq_range *freq_range;
 698         const struct ieee80211_power_rule *power_rule1, *power_rule2;
 699         struct ieee80211_power_rule *power_rule;
 700         u32 freq_diff;
 701
 702         freq_range1 = &rule1->freq_range;
 703         freq_range2 = &rule2->freq_range;
 704         freq_range = &intersected_rule->freq_range;
 705
 706         power_rule1 = &rule1->power_rule;
 707         power_rule2 = &rule2->power_rule;
 708         power_rule = &intersected_rule->power_rule;
 709
 710         freq_range->start_freq_khz = max(freq_range1->start_freq_khz,
 711                 freq_range2->start_freq_khz);
 712         freq_range->end_freq_khz = min(freq_range1->end_freq_khz,
 713                 freq_range2->end_freq_khz);
 714         freq_range->max_bandwidth_khz = min(freq_range1->max_bandwidth_khz,
 715                 freq_range2->max_bandwidth_khz);
 716
 717         freq_diff = freq_range->end_freq_khz - freq_range->start_freq_khz;
 718         if (freq_range->max_bandwidth_khz > freq_diff)
 719                 freq_range->max_bandwidth_khz = freq_diff;
 720
 721         power_rule->max_eirp = min(power_rule1->max_eirp,
 722                 power_rule2->max_eirp);
 723         power_rule->max_antenna_gain = min(power_rule1->max_antenna_gain,
 724                 power_rule2->max_antenna_gain);
 725
 726         intersected_rule->flags = (rule1->flags | rule2->flags);
 727
 728         if (!is_valid_reg_rule(intersected_rule))
 729                 return -EINVAL;
 730
 731         return 0;
 732 }
 733
 734 /**
 735  * regdom_intersect - do the intersection between two regulatory domains
 736  * @rd1: first regulatory domain
 737  * @rd2: second regulatory domain
 738  *
 739  * Use this function to get the intersection between two regulatory domains.
 740  * Once completed we will mark the alpha2 for the rd as intersected, "98",
 741  * as no one single alpha2 can represent this regulatory domain.
 742  *
 743  * Returns a pointer to the regulatory domain structure which will hold the
 744  * resulting intersection of rules between rd1 and rd2. We will
 745  * kzalloc() this structure for you.
 746  */
 747 static struct ieee80211_regdomain *regdom_intersect(
 748         const struct ieee80211_regdomain *rd1,
 749         const struct ieee80211_regdomain *rd2)
 750 {
 751         int r, size_of_regd;
 752         unsigned int x, y;
 753         unsigned int num_rules = 0, rule_idx = 0;
 754         const struct ieee80211_reg_rule *rule1, *rule2;
 755         struct ieee80211_reg_rule *intersected_rule;
 756         struct ieee80211_regdomain *rd;
 757         /* This is just a dummy holder to help us count */
 758         struct ieee80211_reg_rule irule;
 759
 760         /* Uses the stack temporarily for counter arithmetic */
 761         intersected_rule = &irule;
 762
 763         memset(intersected_rule, 0, sizeof(struct ieee80211_reg_rule));
 764
 765         if (!rd1 || !rd2)
 766                 return NULL;
 767
 768         /*
 769          * First we get a count of the rules we'll need, then we actually
 770          * build them. This is to so we can malloc() and free() a
 771          * regdomain once. The reason we use reg_rules_intersect() here
 772          * is it will return -EINVAL if the rule computed makes no sense.
 773          * All rules that do check out OK are valid.
 774          */
 775
 776         for (x = 0; x < rd1->n_reg_rules; x++) {
 777                 rule1 = &rd1->reg_rules[x];
 778                 for (y = 0; y < rd2->n_reg_rules; y++) {
 779                         rule2 = &rd2->reg_rules[y];
 780                         if (!reg_rules_intersect(rule1, rule2,
 781                                         intersected_rule))
 782                                 num_rules++;
 783                         memset(intersected_rule, 0,
 784                                         sizeof(struct ieee80211_reg_rule));
 785                 }
 786         }
 787
 788         if (!num_rules)
 789                 return NULL;
 790
 791         size_of_regd = sizeof(struct ieee80211_regdomain) +
 792                 ((num_rules + 1) * sizeof(struct ieee80211_reg_rule));
 793
 794         rd = kzalloc(size_of_regd, GFP_KERNEL);
 795         if (!rd)
 796                 return NULL;
 797
 798         for (x = 0; x < rd1->n_reg_rules; x++) {
 799                 rule1 = &rd1->reg_rules[x];
 800                 for (y = 0; y < rd2->n_reg_rules; y++) {
 801                         rule2 = &rd2->reg_rules[y];
 802                         /*
 803                          * This time around instead of using the stack lets
 804                          * write to the target rule directly saving ourselves
 805                          * a memcpy()
 806                          */
 807                         intersected_rule = &rd->reg_rules[rule_idx];
 808                         r = reg_rules_intersect(rule1, rule2,
 809                                 intersected_rule);
 810                         /*
 811                          * No need to memset here the intersected rule here as
 812                          * we're not using the stack anymore
 813                          */
 814                         if (r)
 815                                 continue;
 816                         rule_idx++;
 817                 }
 818         }
 819
 820         if (rule_idx != num_rules) {
 821                 kfree(rd);
 822                 return NULL;
 823         }
 824
 825         rd->n_reg_rules = num_rules;
 826         rd->alpha2[0] = '9';
 827         rd->alpha2[1] = '8';
 828
 829         return rd;
 830 }
 831
 832 /*
 833  * XXX: add support for the rest of enum nl80211_reg_rule_flags, we may
 834  * want to just have the channel structure use these
 835  */
 836 static u32 map_regdom_flags(u32 rd_flags)
 837 {
 838         u32 channel_flags = 0;
 839         if (rd_flags & NL80211_RRF_PASSIVE_SCAN)
 840                 channel_flags |= IEEE80211_CHAN_PASSIVE_SCAN;
 841         if (rd_flags & NL80211_RRF_NO_IBSS)
 842                 channel_flags |= IEEE80211_CHAN_NO_IBSS;
 843         if (rd_flags & NL80211_RRF_DFS)
 844                 channel_flags |= IEEE80211_CHAN_RADAR;
 845         return channel_flags;
 846 }
 847
 848 static int freq_reg_info_regd(struct wiphy *wiphy,
 849                               u32 center_freq,
 850                               u32 *bandwidth,
 851                               const struct ieee80211_reg_rule **reg_rule,
 852                               const struct ieee80211_regdomain *custom_regd)
 853 {
 854         int i;
 855         bool band_rule_found = false;
 856         const struct ieee80211_regdomain *regd;
 857         u32 max_bandwidth = 0;
 858
 859         regd = custom_regd ? custom_regd : cfg80211_regdomain;
 860
 861         /*
 862          * Follow the driver's regulatory domain, if present, unless a country
 863          * IE has been processed or a user wants to help complaince further
 864          */
 865         if (last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE &&
 866             last_request->initiator != NL80211_REGDOM_SET_BY_USER &&
 867             wiphy->regd)
 868                 regd = wiphy->regd;
 869
 870         if (!regd)
 871                 return -EINVAL;
 872
 873         for (i = 0; i < regd->n_reg_rules; i++) {
 874                 const struct ieee80211_reg_rule *rr;
 875                 const struct ieee80211_freq_range *fr = NULL;
 876                 const struct ieee80211_power_rule *pr = NULL;
 877
 878                 rr = &regd->reg_rules[i];
 879                 fr = &rr->freq_range;
 880                 pr = &rr->power_rule;
 881
 882                 /*
 883                  * We only need to know if one frequency rule was
 884                  * was in center_freq's band, that's enough, so lets
 885                  * not overwrite it once found
 886                  */
 887                 if (!band_rule_found)
 888                         band_rule_found = freq_in_rule_band(fr, center_freq);
 889
 890                 max_bandwidth = freq_max_bandwidth(fr, center_freq);
 891
 892                 if (max_bandwidth && *bandwidth <= max_bandwidth) {
 893                         *reg_rule = rr;
 894                         *bandwidth = max_bandwidth;
 895                         break;
 896                 }
 897         }
 898
 899         if (!band_rule_found)
 900                 return -ERANGE;
 901
 902         return !max_bandwidth;
 903 }
 904 EXPORT_SYMBOL(freq_reg_info);
 905
 906 int freq_reg_info(struct wiphy *wiphy, u32 center_freq, u32 *bandwidth,
 907                          const struct ieee80211_reg_rule **reg_rule)
 908 {
 909         assert_cfg80211_lock();
 910         return freq_reg_info_regd(wiphy, center_freq,
 911                 bandwidth, reg_rule, NULL);
 912 }
 913
 914 static void handle_channel(struct wiphy *wiphy, enum ieee80211_band band,
 915                            unsigned int chan_idx)
 916 {
 917         int r;
 918         u32 flags;
 919         u32 max_bandwidth = 0;
 920         const struct ieee80211_reg_rule *reg_rule = NULL;
 921         const struct ieee80211_power_rule *power_rule = NULL;
 922         struct ieee80211_supported_band *sband;
 923         struct ieee80211_channel *chan;
 924         struct wiphy *request_wiphy = NULL;
 925
 926         assert_cfg80211_lock();
 927
 928         request_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);
 929
 930         sband = wiphy->bands[band];
 931         BUG_ON(chan_idx >= sband->n_channels);
 932         chan = &sband->channels[chan_idx];
 933
 934         flags = chan->orig_flags;
 935
 936         r = freq_reg_info(wiphy, MHZ_TO_KHZ(chan->center_freq),
 937                 &max_bandwidth, &reg_rule);
 938
 939         if (r) {
 940                 /*
 941                  * This means no regulatory rule was found in the country IE
 942                  * with a frequency range on the center_freq's band, since
 943                  * IEEE-802.11 allows for a country IE to have a subset of the
 944                  * regulatory information provided in a country we ignore
 945                  * disabling the channel unless at least one reg rule was
 946                  * found on the center_freq's band. For details see this
 947                  * clarification:
 948                  *
 949                  * http://tinyurl.com/11d-clarification
 950                  */
 951                 if (r == -ERANGE &&
 952                     last_request->initiator ==
 953                     NL80211_REGDOM_SET_BY_COUNTRY_IE) {
 954 #ifdef CONFIG_CFG80211_REG_DEBUG
 955                         printk(KERN_DEBUG "cfg80211: Leaving channel %d MHz "
 956                                 "intact on %s - no rule found in band on "
 957                                 "Country IE\n",
 958                                 chan->center_freq, wiphy_name(wiphy));
 959 #endif
 960                 } else {
 961                 /*
 962                  * In this case we know the country IE has at least one reg rule
 963                  * for the band so we respect its band definitions
 964                  */
 965 #ifdef CONFIG_CFG80211_REG_DEBUG
 966                         if (last_request->initiator ==
 967                             NL80211_REGDOM_SET_BY_COUNTRY_IE)
 968                                 printk(KERN_DEBUG "cfg80211: Disabling "
 969                                         "channel %d MHz on %s due to "
 970                                         "Country IE\n",
 971                                         chan->center_freq, wiphy_name(wiphy));
 972 #endif
 973                         flags |= IEEE80211_CHAN_DISABLED;
 974                         chan->flags = flags;
 975                 }
 976                 return;
 977         }
 978
 979         power_rule = &reg_rule->power_rule;
 980
 981         if (last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER &&
 982             request_wiphy && request_wiphy == wiphy &&
 983             request_wiphy->strict_regulatory) {
 984                 /*
 985                  * This gaurantees the driver's requested regulatory domain
 986                  * will always be used as a base for further regulatory
 987                  * settings
 988                  */
 989                 chan->flags = chan->orig_flags =
 990                         map_regdom_flags(reg_rule->flags);
 991                 chan->max_antenna_gain = chan->orig_mag =
 992                         (int) MBI_TO_DBI(power_rule->max_antenna_gain);
 993                 chan->max_bandwidth = KHZ_TO_MHZ(max_bandwidth);
 994                 chan->max_power = chan->orig_mpwr =
 995                         (int) MBM_TO_DBM(power_rule->max_eirp);
 996                 return;
 997         }
 998
 999         chan->flags = flags | map_regdom_flags(reg_rule->flags);
1000         chan->max_antenna_gain = min(chan->orig_mag,
1001                 (int) MBI_TO_DBI(power_rule->max_antenna_gain));
1002         chan->max_bandwidth = KHZ_TO_MHZ(max_bandwidth);
1003         if (chan->orig_mpwr)
1004                 chan->max_power = min(chan->orig_mpwr,
1005                         (int) MBM_TO_DBM(power_rule->max_eirp));
1006         else
1007                 chan->max_power = (int) MBM_TO_DBM(power_rule->max_eirp);
1008 }
1009
1010 static void handle_band(struct wiphy *wiphy, enum ieee80211_band band)
1011 {
1012         unsigned int i;
1013         struct ieee80211_supported_band *sband;
1014
1015         BUG_ON(!wiphy->bands[band]);
1016         sband = wiphy->bands[band];
1017
1018         for (i = 0; i < sband->n_channels; i++)
1019                 handle_channel(wiphy, band, i);
1020 }
1021
1022 static bool ignore_reg_update(struct wiphy *wiphy,
1023                               enum nl80211_reg_initiator initiator)
1024 {
1025         if (!last_request)
1026                 return true;
1027         if (initiator == NL80211_REGDOM_SET_BY_CORE &&
1028                   wiphy->custom_regulatory)
1029                 return true;
1030         /*
1031          * wiphy->regd will be set once the device has its own
1032          * desired regulatory domain set
1033          */
1034         if (wiphy->strict_regulatory && !wiphy->regd &&
1035             !is_world_regdom(last_request->alpha2))
1036                 return true;
1037         return false;
1038 }
1039
1040 static void update_all_wiphy_regulatory(enum nl80211_reg_initiator initiator)
1041 {
1042         struct cfg80211_registered_device *drv;
1043
1044         list_for_each_entry(drv, &cfg80211_drv_list, list)
1045                 wiphy_update_regulatory(&drv->wiphy, initiator);
1046 }
1047
1048 static void handle_reg_beacon(struct wiphy *wiphy,
1049                               unsigned int chan_idx,
1050                               struct reg_beacon *reg_beacon)
1051 {
1052         struct ieee80211_supported_band *sband;
1053         struct ieee80211_channel *chan;
1054         bool channel_changed = false;
1055         struct ieee80211_channel chan_before;
1056
1057         assert_cfg80211_lock();
1058
1059         sband = wiphy->bands[reg_beacon->chan.band];
1060         chan = &sband->channels[chan_idx];
1061
1062         if (likely(chan->center_freq != reg_beacon->chan.center_freq))
1063                 return;
1064
1065         if (chan->beacon_found)
1066                 return;
1067
1068         chan->beacon_found = true;
1069
1070         chan_before.center_freq = chan->center_freq;
1071         chan_before.flags = chan->flags;
1072
1073         if ((chan->flags & IEEE80211_CHAN_PASSIVE_SCAN) &&
1074             !(chan->orig_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->orig_flags & IEEE80211_CHAN_NO_IBSS)) {
1081                 chan->flags &= ~IEEE80211_CHAN_NO_IBSS;
1082                 channel_changed = true;
1083         }
1084
1085         if (channel_changed)
1086                 nl80211_send_beacon_hint_event(wiphy, &chan_before, chan);
1087 }
1088
1089 /*
1090  * Called when a scan on a wiphy finds a beacon on
1091  * new channel
1092  */
1093 static void wiphy_update_new_beacon(struct wiphy *wiphy,
1094                                     struct reg_beacon *reg_beacon)
1095 {
1096         unsigned int i;
1097         struct ieee80211_supported_band *sband;
1098
1099         assert_cfg80211_lock();
1100
1101         if (!wiphy->bands[reg_beacon->chan.band])
1102                 return;
1103
1104         sband = wiphy->bands[reg_beacon->chan.band];
1105
1106         for (i = 0; i < sband->n_channels; i++)
1107                 handle_reg_beacon(wiphy, i, reg_beacon);
1108 }
1109
1110 /*
1111  * Called upon reg changes or a new wiphy is added
1112  */
1113 static void wiphy_update_beacon_reg(struct wiphy *wiphy)
1114 {
1115         unsigned int i;
1116         struct ieee80211_supported_band *sband;
1117         struct reg_beacon *reg_beacon;
1118
1119         assert_cfg80211_lock();
1120
1121         if (list_empty(&reg_beacon_list))
1122                 return;
1123
1124         list_for_each_entry(reg_beacon, &reg_beacon_list, list) {
1125                 if (!wiphy->bands[reg_beacon->chan.band])
1126                         continue;
1127                 sband = wiphy->bands[reg_beacon->chan.band];
1128                 for (i = 0; i < sband->n_channels; i++)
1129                         handle_reg_beacon(wiphy, i, reg_beacon);
1130         }
1131 }
1132
1133 static bool reg_is_world_roaming(struct wiphy *wiphy)
1134 {
1135         if (is_world_regdom(cfg80211_regdomain->alpha2) ||
1136             (wiphy->regd && is_world_regdom(wiphy->regd->alpha2)))
1137                 return true;
1138         if (last_request &&
1139             last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE &&
1140             wiphy->custom_regulatory)
1141                 return true;
1142         return false;
1143 }
1144
1145 /* Reap the advantages of previously found beacons */
1146 static void reg_process_beacons(struct wiphy *wiphy)
1147 {
1148         /*
1149          * Means we are just firing up cfg80211, so no beacons would
1150          * have been processed yet.
1151          */
1152         if (!last_request)
1153                 return;
1154         if (!reg_is_world_roaming(wiphy))
1155                 return;
1156         wiphy_update_beacon_reg(wiphy);
1157 }
1158
1159 void wiphy_update_regulatory(struct wiphy *wiphy,
1160                              enum nl80211_reg_initiator initiator)
1161 {
1162         enum ieee80211_band band;
1163
1164         if (ignore_reg_update(wiphy, initiator))
1165                 goto out;
1166         for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
1167                 if (wiphy->bands[band])
1168                         handle_band(wiphy, band);
1169         }
1170 out:
1171         reg_process_beacons(wiphy);
1172         if (wiphy->reg_notifier)
1173                 wiphy->reg_notifier(wiphy, last_request);
1174 }
1175
1176 static void handle_channel_custom(struct wiphy *wiphy,
1177                                   enum ieee80211_band band,
1178                                   unsigned int chan_idx,
1179                                   const struct ieee80211_regdomain *regd)
1180 {
1181         int r;
1182         u32 max_bandwidth = 0;
1183         const struct ieee80211_reg_rule *reg_rule = NULL;
1184         const struct ieee80211_power_rule *power_rule = NULL;
1185         struct ieee80211_supported_band *sband;
1186         struct ieee80211_channel *chan;
1187
1188         assert_cfg80211_lock();
1189
1190         sband = wiphy->bands[band];
1191         BUG_ON(chan_idx >= sband->n_channels);
1192         chan = &sband->channels[chan_idx];
1193
1194         r = freq_reg_info_regd(wiphy, MHZ_TO_KHZ(chan->center_freq),
1195                 &max_bandwidth, &reg_rule, regd);
1196
1197         if (r) {
1198                 chan->flags = IEEE80211_CHAN_DISABLED;
1199                 return;
1200         }
1201
1202         power_rule = &reg_rule->power_rule;
1203
1204         chan->flags |= map_regdom_flags(reg_rule->flags);
1205         chan->max_antenna_gain = (int) MBI_TO_DBI(power_rule->max_antenna_gain);
1206         chan->max_bandwidth = KHZ_TO_MHZ(max_bandwidth);
1207         chan->max_power = (int) MBM_TO_DBM(power_rule->max_eirp);
1208 }
1209
1210 static void handle_band_custom(struct wiphy *wiphy, enum ieee80211_band band,
1211                                const struct ieee80211_regdomain *regd)
1212 {
1213         unsigned int i;
1214         struct ieee80211_supported_band *sband;
1215
1216         BUG_ON(!wiphy->bands[band]);
1217         sband = wiphy->bands[band];
1218
1219         for (i = 0; i < sband->n_channels; i++)
1220                 handle_channel_custom(wiphy, band, i, regd);
1221 }
1222
1223 /* Used by drivers prior to wiphy registration */
1224 void wiphy_apply_custom_regulatory(struct wiphy *wiphy,
1225                                    const struct ieee80211_regdomain *regd)
1226 {
1227         enum ieee80211_band band;
1228
1229         mutex_lock(&cfg80211_mutex);
1230         for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
1231                 if (wiphy->bands[band])
1232                         handle_band_custom(wiphy, band, regd);
1233         }
1234         mutex_unlock(&cfg80211_mutex);
1235 }
1236 EXPORT_SYMBOL(wiphy_apply_custom_regulatory);
1237
1238 static int reg_copy_regd(const struct ieee80211_regdomain **dst_regd,
1239                          const struct ieee80211_regdomain *src_regd)
1240 {
1241         struct ieee80211_regdomain *regd;
1242         int size_of_regd = 0;
1243         unsigned int i;
1244
1245         size_of_regd = sizeof(struct ieee80211_regdomain) +
1246           ((src_regd->n_reg_rules + 1) * sizeof(struct ieee80211_reg_rule));
1247
1248         regd = kzalloc(size_of_regd, GFP_KERNEL);
1249         if (!regd)
1250                 return -ENOMEM;
1251
1252         memcpy(regd, src_regd, sizeof(struct ieee80211_regdomain));
1253
1254         for (i = 0; i < src_regd->n_reg_rules; i++)
1255                 memcpy(&regd->reg_rules[i], &src_regd->reg_rules[i],
1256                         sizeof(struct ieee80211_reg_rule));
1257
1258         *dst_regd = regd;
1259         return 0;
1260 }
1261
1262 /*
1263  * Return value which can be used by ignore_request() to indicate
1264  * it has been determined we should intersect two regulatory domains
1265  */
1266 #define REG_INTERSECT   1
1267
1268 /* This has the logic which determines when a new request
1269  * should be ignored. */
1270 static int ignore_request(struct wiphy *wiphy,
1271                           struct regulatory_request *pending_request)
1272 {
1273         struct wiphy *last_wiphy = NULL;
1274
1275         assert_cfg80211_lock();
1276
1277         /* All initial requests are respected */
1278         if (!last_request)
1279                 return 0;
1280
1281         switch (pending_request->initiator) {
1282         case NL80211_REGDOM_SET_BY_CORE:
1283                 return -EINVAL;
1284         case NL80211_REGDOM_SET_BY_COUNTRY_IE:
1285
1286                 last_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);
1287
1288                 if (unlikely(!is_an_alpha2(pending_request->alpha2)))
1289                         return -EINVAL;
1290                 if (last_request->initiator ==
1291                     NL80211_REGDOM_SET_BY_COUNTRY_IE) {
1292                         if (last_wiphy != wiphy) {
1293                                 /*
1294                                  * Two cards with two APs claiming different
1295                                  * different Country IE alpha2s. We could
1296                                  * intersect them, but that seems unlikely
1297                                  * to be correct. Reject second one for now.
1298                                  */
1299                                 if (regdom_changes(pending_request->alpha2))
1300                                         return -EOPNOTSUPP;
1301                                 return -EALREADY;
1302                         }
1303                         /*
1304                          * Two consecutive Country IE hints on the same wiphy.
1305                          * This should be picked up early by the driver/stack
1306                          */
1307                         if (WARN_ON(regdom_changes(pending_request->alpha2)))
1308                                 return 0;
1309                         return -EALREADY;
1310                 }
1311                 return REG_INTERSECT;
1312         case NL80211_REGDOM_SET_BY_DRIVER:
1313                 if (last_request->initiator == NL80211_REGDOM_SET_BY_CORE) {
1314                         if (is_old_static_regdom(cfg80211_regdomain))
1315                                 return 0;
1316                         if (regdom_changes(pending_request->alpha2))
1317                                 return 0;
1318                         return -EALREADY;
1319                 }
1320
1321                 /*
1322                  * This would happen if you unplug and plug your card
1323                  * back in or if you add a new device for which the previously
1324                  * loaded card also agrees on the regulatory domain.
1325                  */
1326                 if (last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER &&
1327                     !regdom_changes(pending_request->alpha2))
1328                         return -EALREADY;
1329
1330                 return REG_INTERSECT;
1331         case NL80211_REGDOM_SET_BY_USER:
1332                 if (last_request->initiator == NL80211_REGDOM_SET_BY_COUNTRY_IE)
1333                         return REG_INTERSECT;
1334                 /*
1335                  * If the user knows better the user should set the regdom
1336                  * to their country before the IE is picked up
1337                  */
1338                 if (last_request->initiator == NL80211_REGDOM_SET_BY_USER &&
1339                           last_request->intersect)
1340                         return -EOPNOTSUPP;
1341                 /*
1342                  * Process user requests only after previous user/driver/core
1343                  * requests have been processed
1344                  */
1345                 if (last_request->initiator == NL80211_REGDOM_SET_BY_CORE ||
1346                     last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER ||
1347                     last_request->initiator == NL80211_REGDOM_SET_BY_USER) {
1348                         if (regdom_changes(last_request->alpha2))
1349                                 return -EAGAIN;
1350                 }
1351
1352                 if (!is_old_static_regdom(cfg80211_regdomain) &&
1353                     !regdom_changes(pending_request->alpha2))
1354                         return -EALREADY;
1355
1356                 return 0;
1357         }
1358
1359         return -EINVAL;
1360 }
1361
1362 /**
1363  * __regulatory_hint - hint to the wireless core a regulatory domain
1364  * @wiphy: if the hint comes from country information from an AP, this
1365  *      is required to be set to the wiphy that received the information
1366  * @pending_request: the regulatory request currently being processed
1367  *
1368  * The Wireless subsystem can use this function to hint to the wireless core
1369  * what it believes should be the current regulatory domain.
1370  *
1371  * Returns zero if all went fine, %-EALREADY if a regulatory domain had
1372  * already been set or other standard error codes.
1373  *
1374  * Caller must hold &cfg80211_mutex
1375  */
1376 static int __regulatory_hint(struct wiphy *wiphy,
1377                              struct regulatory_request *pending_request)
1378 {
1379         bool intersect = false;
1380         int r = 0;
1381
1382         assert_cfg80211_lock();
1383
1384         r = ignore_request(wiphy, pending_request);
1385
1386         if (r == REG_INTERSECT) {
1387                 if (pending_request->initiator ==
1388                     NL80211_REGDOM_SET_BY_DRIVER) {
1389                         r = reg_copy_regd(&wiphy->regd, cfg80211_regdomain);
1390                         if (r) {
1391                                 kfree(pending_request);
1392                                 return r;
1393                         }
1394                 }
1395                 intersect = true;
1396         } else if (r) {
1397                 /*
1398                  * If the regulatory domain being requested by the
1399                  * driver has already been set just copy it to the
1400                  * wiphy
1401                  */
1402                 if (r == -EALREADY &&
1403                     pending_request->initiator ==
1404                     NL80211_REGDOM_SET_BY_DRIVER) {
1405                         r = reg_copy_regd(&wiphy->regd, cfg80211_regdomain);
1406                         if (r) {
1407                                 kfree(pending_request);
1408                                 return r;
1409                         }
1410                         r = -EALREADY;
1411                         goto new_request;
1412                 }
1413                 kfree(pending_request);
1414                 return r;
1415         }
1416
1417 new_request:
1418         kfree(last_request);
1419
1420         last_request = pending_request;
1421         last_request->intersect = intersect;
1422
1423         pending_request = NULL;
1424
1425         /* When r == REG_INTERSECT we do need to call CRDA */
1426         if (r < 0) {
1427                 /*
1428                  * Since CRDA will not be called in this case as we already
1429                  * have applied the requested regulatory domain before we just
1430                  * inform userspace we have processed the request
1431                  */
1432                 if (r == -EALREADY)
1433                         nl80211_send_reg_change_event(last_request);
1434                 return r;
1435         }
1436
1437         return call_crda(last_request->alpha2);
1438 }
1439
1440 /* This processes *all* regulatory hints */
1441 static void reg_process_hint(struct regulatory_request *reg_request)
1442 {
1443         int r = 0;
1444         struct wiphy *wiphy = NULL;
1445
1446         BUG_ON(!reg_request->alpha2);
1447
1448         mutex_lock(&cfg80211_mutex);
1449
1450         if (wiphy_idx_valid(reg_request->wiphy_idx))
1451                 wiphy = wiphy_idx_to_wiphy(reg_request->wiphy_idx);
1452
1453         if (reg_request->initiator == NL80211_REGDOM_SET_BY_DRIVER &&
1454             !wiphy) {
1455                 kfree(reg_request);
1456                 goto out;
1457         }
1458
1459         r = __regulatory_hint(wiphy, reg_request);
1460         /* This is required so that the orig_* parameters are saved */
1461         if (r == -EALREADY && wiphy && wiphy->strict_regulatory)
1462                 wiphy_update_regulatory(wiphy, reg_request->initiator);
1463 out:
1464         mutex_unlock(&cfg80211_mutex);
1465 }
1466
1467 /* Processes regulatory hints, this is all the NL80211_REGDOM_SET_BY_* */
1468 static void reg_process_pending_hints(void)
1469         {
1470         struct regulatory_request *reg_request;
1471
1472         spin_lock(&reg_requests_lock);
1473         while (!list_empty(&reg_requests_list)) {
1474                 reg_request = list_first_entry(&reg_requests_list,
1475                                                struct regulatory_request,
1476                                                list);
1477                 list_del_init(&reg_request->list);
1478
1479                 spin_unlock(&reg_requests_lock);
1480                 reg_process_hint(reg_request);
1481                 spin_lock(&reg_requests_lock);
1482         }
1483         spin_unlock(&reg_requests_lock);
1484 }
1485
1486 /* Processes beacon hints -- this has nothing to do with country IEs */
1487 static void reg_process_pending_beacon_hints(void)
1488 {
1489         struct cfg80211_registered_device *drv;
1490         struct reg_beacon *pending_beacon, *tmp;
1491
1492         mutex_lock(&cfg80211_mutex);
1493
1494         /* This goes through the _pending_ beacon list */
1495         spin_lock_bh(&reg_pending_beacons_lock);
1496
1497         if (list_empty(&reg_pending_beacons)) {
1498                 spin_unlock_bh(&reg_pending_beacons_lock);
1499                 goto out;
1500         }
1501
1502         list_for_each_entry_safe(pending_beacon, tmp,
1503                                  &reg_pending_beacons, list) {
1504
1505                 list_del_init(&pending_beacon->list);
1506
1507                 /* Applies the beacon hint to current wiphys */
1508                 list_for_each_entry(drv, &cfg80211_drv_list, list)
1509                         wiphy_update_new_beacon(&drv->wiphy, pending_beacon);
1510
1511                 /* Remembers the beacon hint for new wiphys or reg changes */
1512                 list_add_tail(&pending_beacon->list, &reg_beacon_list);
1513         }
1514
1515         spin_unlock_bh(&reg_pending_beacons_lock);
1516 out:
1517         mutex_unlock(&cfg80211_mutex);
1518 }
1519
1520 static void reg_todo(struct work_struct *work)
1521 {
1522         reg_process_pending_hints();
1523         reg_process_pending_beacon_hints();
1524 }
1525
1526 static DECLARE_WORK(reg_work, reg_todo);
1527
1528 static void queue_regulatory_request(struct regulatory_request *request)
1529 {
1530         spin_lock(&reg_requests_lock);
1531         list_add_tail(&request->list, &reg_requests_list);
1532         spin_unlock(&reg_requests_lock);
1533
1534         schedule_work(&reg_work);
1535 }
1536
1537 /* Core regulatory hint -- happens once during cfg80211_init() */
1538 static int regulatory_hint_core(const char *alpha2)
1539 {
1540         struct regulatory_request *request;
1541
1542         BUG_ON(last_request);
1543
1544         request = kzalloc(sizeof(struct regulatory_request),
1545                           GFP_KERNEL);
1546         if (!request)
1547                 return -ENOMEM;
1548
1549         request->alpha2[0] = alpha2[0];
1550         request->alpha2[1] = alpha2[1];
1551         request->initiator = NL80211_REGDOM_SET_BY_CORE;
1552
1553         queue_regulatory_request(request);
1554
1555         return 0;
1556 }
1557
1558 /* User hints */
1559 int regulatory_hint_user(const char *alpha2)
1560 {
1561         struct regulatory_request *request;
1562
1563         BUG_ON(!alpha2);
1564
1565         request = kzalloc(sizeof(struct regulatory_request), GFP_KERNEL);
1566         if (!request)
1567                 return -ENOMEM;
1568
1569         request->wiphy_idx = WIPHY_IDX_STALE;
1570         request->alpha2[0] = alpha2[0];
1571         request->alpha2[1] = alpha2[1];
1572         request->initiator = NL80211_REGDOM_SET_BY_USER,
1573
1574         queue_regulatory_request(request);
1575
1576         return 0;
1577 }
1578
1579 /* Driver hints */
1580 int regulatory_hint(struct wiphy *wiphy, const char *alpha2)
1581 {
1582         struct regulatory_request *request;
1583
1584         BUG_ON(!alpha2);
1585         BUG_ON(!wiphy);
1586
1587         request = kzalloc(sizeof(struct regulatory_request), GFP_KERNEL);
1588         if (!request)
1589                 return -ENOMEM;
1590
1591         request->wiphy_idx = get_wiphy_idx(wiphy);
1592
1593         /* Must have registered wiphy first */
1594         BUG_ON(!wiphy_idx_valid(request->wiphy_idx));
1595
1596         request->alpha2[0] = alpha2[0];
1597         request->alpha2[1] = alpha2[1];
1598         request->initiator = NL80211_REGDOM_SET_BY_DRIVER;
1599
1600         queue_regulatory_request(request);
1601
1602         return 0;
1603 }
1604 EXPORT_SYMBOL(regulatory_hint);
1605
1606 static bool reg_same_country_ie_hint(struct wiphy *wiphy,
1607                         u32 country_ie_checksum)
1608 {
1609         struct wiphy *request_wiphy;
1610
1611         assert_cfg80211_lock();
1612
1613         if (unlikely(last_request->initiator !=
1614             NL80211_REGDOM_SET_BY_COUNTRY_IE))
1615                 return false;
1616
1617         request_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);
1618
1619         if (!request_wiphy)
1620                 return false;
1621
1622         if (likely(request_wiphy != wiphy))
1623                 return !country_ie_integrity_changes(country_ie_checksum);
1624         /*
1625          * We should not have let these through at this point, they
1626          * should have been picked up earlier by the first alpha2 check
1627          * on the device
1628          */
1629         if (WARN_ON(!country_ie_integrity_changes(country_ie_checksum)))
1630                 return true;
1631         return false;
1632 }
1633
1634 void regulatory_hint_11d(struct wiphy *wiphy,
1635                         u8 *country_ie,
1636                         u8 country_ie_len)
1637 {
1638         struct ieee80211_regdomain *rd = NULL;
1639         char alpha2[2];
1640         u32 checksum = 0;
1641         enum environment_cap env = ENVIRON_ANY;
1642         struct regulatory_request *request;
1643
1644         mutex_lock(&cfg80211_mutex);
1645
1646         if (unlikely(!last_request)) {
1647                 mutex_unlock(&cfg80211_mutex);
1648                 return;
1649         }
1650
1651         /* IE len must be evenly divisible by 2 */
1652         if (country_ie_len & 0x01)
1653                 goto out;
1654
1655         if (country_ie_len < IEEE80211_COUNTRY_IE_MIN_LEN)
1656                 goto out;
1657
1658         /*
1659          * Pending country IE processing, this can happen after we
1660          * call CRDA and wait for a response if a beacon was received before
1661          * we were able to process the last regulatory_hint_11d() call
1662          */
1663         if (country_ie_regdomain)
1664                 goto out;
1665
1666         alpha2[0] = country_ie[0];
1667         alpha2[1] = country_ie[1];
1668
1669         if (country_ie[2] == 'I')
1670                 env = ENVIRON_INDOOR;
1671         else if (country_ie[2] == 'O')
1672                 env = ENVIRON_OUTDOOR;
1673
1674         /*
1675          * We will run this for *every* beacon processed for the BSSID, so
1676          * we optimize an early check to exit out early if we don't have to
1677          * do anything
1678          */
1679         if (likely(last_request->initiator ==
1680             NL80211_REGDOM_SET_BY_COUNTRY_IE &&
1681             wiphy_idx_valid(last_request->wiphy_idx))) {
1682                 struct cfg80211_registered_device *drv_last_ie;
1683
1684                 drv_last_ie =
1685                         cfg80211_drv_by_wiphy_idx(last_request->wiphy_idx);
1686
1687                 /*
1688                  * Lets keep this simple -- we trust the first AP
1689                  * after we intersect with CRDA
1690                  */
1691                 if (likely(&drv_last_ie->wiphy == wiphy)) {
1692                         /*
1693                          * Ignore IEs coming in on this wiphy with
1694                          * the same alpha2 and environment cap
1695                          */
1696                         if (likely(alpha2_equal(drv_last_ie->country_ie_alpha2,
1697                                   alpha2) &&
1698                                   env == drv_last_ie->env)) {
1699                                 goto out;
1700                         }
1701                         /*
1702                          * the wiphy moved on to another BSSID or the AP
1703                          * was reconfigured. XXX: We need to deal with the
1704                          * case where the user suspends and goes to goes
1705                          * to another country, and then gets IEs from an
1706                          * AP with different settings
1707                          */
1708                         goto out;
1709                 } else {
1710                         /*
1711                          * Ignore IEs coming in on two separate wiphys with
1712                          * the same alpha2 and environment cap
1713                          */
1714                         if (likely(alpha2_equal(drv_last_ie->country_ie_alpha2,
1715                                   alpha2) &&
1716                                   env == drv_last_ie->env)) {
1717                                 goto out;
1718                         }
1719                         /* We could potentially intersect though */
1720                         goto out;
1721                 }
1722         }
1723
1724         rd = country_ie_2_rd(country_ie, country_ie_len, &checksum);
1725         if (!rd)
1726                 goto out;
1727
1728         /*
1729          * This will not happen right now but we leave it here for the
1730          * the future when we want to add suspend/resume support and having
1731          * the user move to another country after doing so, or having the user
1732          * move to another AP. Right now we just trust the first AP.
1733          *
1734          * If we hit this before we add this support we want to be informed of
1735          * it as it would indicate a mistake in the current design
1736          */
1737         if (WARN_ON(reg_same_country_ie_hint(wiphy, checksum)))
1738                 goto free_rd_out;
1739
1740         request = kzalloc(sizeof(struct regulatory_request), GFP_KERNEL);
1741         if (!request)
1742                 goto free_rd_out;
1743
1744         /*
1745          * We keep this around for when CRDA comes back with a response so
1746          * we can intersect with that
1747          */
1748         country_ie_regdomain = rd;
1749
1750         request->wiphy_idx = get_wiphy_idx(wiphy);
1751         request->alpha2[0] = rd->alpha2[0];
1752         request->alpha2[1] = rd->alpha2[1];
1753         request->initiator = NL80211_REGDOM_SET_BY_COUNTRY_IE;
1754         request->country_ie_checksum = checksum;
1755         request->country_ie_env = env;
1756
1757         mutex_unlock(&cfg80211_mutex);
1758
1759         queue_regulatory_request(request);
1760
1761         return;
1762
1763 free_rd_out:
1764         kfree(rd);
1765 out:
1766         mutex_unlock(&cfg80211_mutex);
1767 }
1768 EXPORT_SYMBOL(regulatory_hint_11d);
1769
1770 static bool freq_is_chan_12_13_14(u16 freq)
1771 {
1772         if (freq == ieee80211_channel_to_frequency(12) ||
1773             freq == ieee80211_channel_to_frequency(13) ||
1774             freq == ieee80211_channel_to_frequency(14))
1775                 return true;
1776         return false;
1777 }
1778
1779 int regulatory_hint_found_beacon(struct wiphy *wiphy,
1780                                  struct ieee80211_channel *beacon_chan,
1781                                  gfp_t gfp)
1782 {
1783         struct reg_beacon *reg_beacon;
1784
1785         if (likely((beacon_chan->beacon_found ||
1786             (beacon_chan->flags & IEEE80211_CHAN_RADAR) ||
1787             (beacon_chan->band == IEEE80211_BAND_2GHZ &&
1788              !freq_is_chan_12_13_14(beacon_chan->center_freq)))))
1789                 return 0;
1790
1791         reg_beacon = kzalloc(sizeof(struct reg_beacon), gfp);
1792         if (!reg_beacon)
1793                 return -ENOMEM;
1794
1795 #ifdef CONFIG_CFG80211_REG_DEBUG
1796         printk(KERN_DEBUG "cfg80211: Found new beacon on "
1797                 "frequency: %d MHz (Ch %d) on %s\n",
1798                 beacon_chan->center_freq,
1799                 ieee80211_frequency_to_channel(beacon_chan->center_freq),
1800                 wiphy_name(wiphy));
1801 #endif
1802         memcpy(&reg_beacon->chan, beacon_chan,
1803                 sizeof(struct ieee80211_channel));
1804
1805
1806         /*
1807          * Since we can be called from BH or and non-BH context
1808          * we must use spin_lock_bh()
1809          */
1810         spin_lock_bh(&reg_pending_beacons_lock);
1811         list_add_tail(&reg_beacon->list, &reg_pending_beacons);
1812         spin_unlock_bh(&reg_pending_beacons_lock);
1813
1814         schedule_work(&reg_work);
1815
1816         return 0;
1817 }
1818
1819 static void print_rd_rules(const struct ieee80211_regdomain *rd)
1820 {
1821         unsigned int i;
1822         const struct ieee80211_reg_rule *reg_rule = NULL;
1823         const struct ieee80211_freq_range *freq_range = NULL;
1824         const struct ieee80211_power_rule *power_rule = NULL;
1825
1826         printk(KERN_INFO "\t(start_freq - end_freq @ bandwidth), "
1827                 "(max_antenna_gain, max_eirp)\n");
1828
1829         for (i = 0; i < rd->n_reg_rules; i++) {
1830                 reg_rule = &rd->reg_rules[i];
1831                 freq_range = &reg_rule->freq_range;
1832                 power_rule = &reg_rule->power_rule;
1833
1834                 /*
1835                  * There may not be documentation for max antenna gain
1836                  * in certain regions
1837                  */
1838                 if (power_rule->max_antenna_gain)
1839                         printk(KERN_INFO "\t(%d KHz - %d KHz @ %d KHz), "
1840                                 "(%d mBi, %d mBm)\n",
1841                                 freq_range->start_freq_khz,
1842                                 freq_range->end_freq_khz,
1843                                 freq_range->max_bandwidth_khz,
1844                                 power_rule->max_antenna_gain,
1845                                 power_rule->max_eirp);
1846                 else
1847                         printk(KERN_INFO "\t(%d KHz - %d KHz @ %d KHz), "
1848                                 "(N/A, %d mBm)\n",
1849                                 freq_range->start_freq_khz,
1850                                 freq_range->end_freq_khz,
1851                                 freq_range->max_bandwidth_khz,
1852                                 power_rule->max_eirp);
1853         }
1854 }
1855
1856 static void print_regdomain(const struct ieee80211_regdomain *rd)
1857 {
1858
1859         if (is_intersected_alpha2(rd->alpha2)) {
1860
1861                 if (last_request->initiator ==
1862                     NL80211_REGDOM_SET_BY_COUNTRY_IE) {
1863                         struct cfg80211_registered_device *drv;
1864                         drv = cfg80211_drv_by_wiphy_idx(
1865                                 last_request->wiphy_idx);
1866                         if (drv) {
1867                                 printk(KERN_INFO "cfg80211: Current regulatory "
1868                                         "domain updated by AP to: %c%c\n",
1869                                         drv->country_ie_alpha2[0],
1870                                         drv->country_ie_alpha2[1]);
1871                         } else
1872                                 printk(KERN_INFO "cfg80211: Current regulatory "
1873                                         "domain intersected: \n");
1874                 } else
1875                                 printk(KERN_INFO "cfg80211: Current regulatory "
1876                                         "domain intersected: \n");
1877         } else if (is_world_regdom(rd->alpha2))
1878                 printk(KERN_INFO "cfg80211: World regulatory "
1879                         "domain updated:\n");
1880         else {
1881                 if (is_unknown_alpha2(rd->alpha2))
1882                         printk(KERN_INFO "cfg80211: Regulatory domain "
1883                                 "changed to driver built-in settings "
1884                                 "(unknown country)\n");
1885                 else
1886                         printk(KERN_INFO "cfg80211: Regulatory domain "
1887                                 "changed to country: %c%c\n",
1888                                 rd->alpha2[0], rd->alpha2[1]);
1889         }
1890         print_rd_rules(rd);
1891 }
1892
1893 static void print_regdomain_info(const struct ieee80211_regdomain *rd)
1894 {
1895         printk(KERN_INFO "cfg80211: Regulatory domain: %c%c\n",
1896                 rd->alpha2[0], rd->alpha2[1]);
1897         print_rd_rules(rd);
1898 }
1899
1900 #ifdef CONFIG_CFG80211_REG_DEBUG
1901 static void reg_country_ie_process_debug(
1902         const struct ieee80211_regdomain *rd,
1903         const struct ieee80211_regdomain *country_ie_regdomain,
1904         const struct ieee80211_regdomain *intersected_rd)
1905 {
1906         printk(KERN_DEBUG "cfg80211: Received country IE:\n");
1907         print_regdomain_info(country_ie_regdomain);
1908         printk(KERN_DEBUG "cfg80211: CRDA thinks this should applied:\n");
1909         print_regdomain_info(rd);
1910         if (intersected_rd) {
1911                 printk(KERN_DEBUG "cfg80211: We intersect both of these "
1912                         "and get:\n");
1913                 print_regdomain_info(intersected_rd);
1914                 return;
1915         }
1916         printk(KERN_DEBUG "cfg80211: Intersection between both failed\n");
1917 }
1918 #else
1919 static inline void reg_country_ie_process_debug(
1920         const struct ieee80211_regdomain *rd,
1921         const struct ieee80211_regdomain *country_ie_regdomain,
1922         const struct ieee80211_regdomain *intersected_rd)
1923 {
1924 }
1925 #endif
1926
1927 /* Takes ownership of rd only if it doesn't fail */
1928 static int __set_regdom(const struct ieee80211_regdomain *rd)
1929 {
1930         const struct ieee80211_regdomain *intersected_rd = NULL;
1931         struct cfg80211_registered_device *drv = NULL;
1932         struct wiphy *request_wiphy;
1933         /* Some basic sanity checks first */
1934
1935         if (is_world_regdom(rd->alpha2)) {
1936                 if (WARN_ON(!reg_is_valid_request(rd->alpha2)))
1937                         return -EINVAL;
1938                 update_world_regdomain(rd);
1939                 return 0;
1940         }
1941
1942         if (!is_alpha2_set(rd->alpha2) && !is_an_alpha2(rd->alpha2) &&
1943                         !is_unknown_alpha2(rd->alpha2))
1944                 return -EINVAL;
1945
1946         if (!last_request)
1947                 return -EINVAL;
1948
1949         /*
1950          * Lets only bother proceeding on the same alpha2 if the current
1951          * rd is non static (it means CRDA was present and was used last)
1952          * and the pending request came in from a country IE
1953          */
1954         if (last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE) {
1955                 /*
1956                  * If someone else asked us to change the rd lets only bother
1957                  * checking if the alpha2 changes if CRDA was already called
1958                  */
1959                 if (!is_old_static_regdom(cfg80211_regdomain) &&
1960                     !regdom_changes(rd->alpha2))
1961                         return -EINVAL;
1962         }
1963
1964         /*
1965          * Now lets set the regulatory domain, update all driver channels
1966          * and finally inform them of what we have done, in case they want
1967          * to review or adjust their own settings based on their own
1968          * internal EEPROM data
1969          */
1970
1971         if (WARN_ON(!reg_is_valid_request(rd->alpha2)))
1972                 return -EINVAL;
1973
1974         if (!is_valid_rd(rd)) {
1975                 printk(KERN_ERR "cfg80211: Invalid "
1976                         "regulatory domain detected:\n");
1977                 print_regdomain_info(rd);
1978                 return -EINVAL;
1979         }
1980
1981         request_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);
1982
1983         if (!last_request->intersect) {
1984                 int r;
1985
1986                 if (last_request->initiator != NL80211_REGDOM_SET_BY_DRIVER) {
1987                         reset_regdomains();
1988                         cfg80211_regdomain = rd;
1989                         return 0;
1990                 }
1991
1992                 /*
1993                  * For a driver hint, lets copy the regulatory domain the
1994                  * driver wanted to the wiphy to deal with conflicts
1995                  */
1996
1997                 BUG_ON(request_wiphy->regd);
1998
1999                 r = reg_copy_regd(&request_wiphy->regd, rd);
2000                 if (r)
2001                         return r;
2002
2003                 reset_regdomains();
2004                 cfg80211_regdomain = rd;
2005                 return 0;
2006         }
2007
2008         /* Intersection requires a bit more work */
2009
2010         if (last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE) {
2011
2012                 intersected_rd = regdom_intersect(rd, cfg80211_regdomain);
2013                 if (!intersected_rd)
2014                         return -EINVAL;
2015
2016                 /*
2017                  * We can trash what CRDA provided now.
2018                  * However if a driver requested this specific regulatory
2019                  * domain we keep it for its private use
2020                  */
2021                 if (last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER)
2022                         request_wiphy->regd = rd;
2023                 else
2024                         kfree(rd);
2025
2026                 rd = NULL;
2027
2028                 reset_regdomains();
2029                 cfg80211_regdomain = intersected_rd;
2030
2031                 return 0;
2032         }
2033
2034         /*
2035          * Country IE requests are handled a bit differently, we intersect
2036          * the country IE rd with what CRDA believes that country should have
2037          */
2038
2039         BUG_ON(!country_ie_regdomain);
2040         BUG_ON(rd == country_ie_regdomain);
2041
2042         /*
2043          * Intersect what CRDA returned and our what we
2044          * had built from the Country IE received
2045          */
2046
2047         intersected_rd = regdom_intersect(rd, country_ie_regdomain);
2048
2049         reg_country_ie_process_debug(rd,
2050                                      country_ie_regdomain,
2051                                      intersected_rd);
2052
2053         kfree(country_ie_regdomain);
2054         country_ie_regdomain = NULL;
2055
2056         if (!intersected_rd)
2057                 return -EINVAL;
2058
2059         drv = wiphy_to_dev(request_wiphy);
2060
2061         drv->country_ie_alpha2[0] = rd->alpha2[0];
2062         drv->country_ie_alpha2[1] = rd->alpha2[1];
2063         drv->env = last_request->country_ie_env;
2064
2065         BUG_ON(intersected_rd == rd);
2066
2067         kfree(rd);
2068         rd = NULL;
2069
2070         reset_regdomains();
2071         cfg80211_regdomain = intersected_rd;
2072
2073         return 0;
2074 }
2075
2076
2077 /*
2078  * Use this call to set the current regulatory domain. Conflicts with
2079  * multiple drivers can be ironed out later. Caller must've already
2080  * kmalloc'd the rd structure. Caller must hold cfg80211_mutex
2081  */
2082 int set_regdom(const struct ieee80211_regdomain *rd)
2083 {
2084         int r;
2085
2086         assert_cfg80211_lock();
2087
2088         /* Note that this doesn't update the wiphys, this is done below */
2089         r = __set_regdom(rd);
2090         if (r) {
2091                 kfree(rd);
2092                 return r;
2093         }
2094
2095         /* This would make this whole thing pointless */
2096         if (!last_request->intersect)
2097                 BUG_ON(rd != cfg80211_regdomain);
2098
2099         /* update all wiphys now with the new established regulatory domain */
2100         update_all_wiphy_regulatory(last_request->initiator);
2101
2102         print_regdomain(cfg80211_regdomain);
2103
2104         nl80211_send_reg_change_event(last_request);
2105
2106         return r;
2107 }
2108
2109 /* Caller must hold cfg80211_mutex */
2110 void reg_device_remove(struct wiphy *wiphy)
2111 {
2112         struct wiphy *request_wiphy = NULL;
2113
2114         assert_cfg80211_lock();
2115
2116         kfree(wiphy->regd);
2117
2118         if (last_request)
2119                 request_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);
2120
2121         if (!request_wiphy || request_wiphy != wiphy)
2122                 return;
2123
2124         last_request->wiphy_idx = WIPHY_IDX_STALE;
2125         last_request->country_ie_env = ENVIRON_ANY;
2126 }
2127
2128 int regulatory_init(void)
2129 {
2130         int err = 0;
2131
2132         reg_pdev = platform_device_register_simple("regulatory", 0, NULL, 0);
2133         if (IS_ERR(reg_pdev))
2134                 return PTR_ERR(reg_pdev);
2135
2136         spin_lock_init(&reg_requests_lock);
2137         spin_lock_init(&reg_pending_beacons_lock);
2138
2139 #ifdef CONFIG_WIRELESS_OLD_REGULATORY
2140         cfg80211_regdomain = static_regdom(ieee80211_regdom);
2141
2142         printk(KERN_INFO "cfg80211: Using static regulatory domain info\n");
2143         print_regdomain_info(cfg80211_regdomain);
2144         /*
2145          * The old code still requests for a new regdomain and if
2146          * you have CRDA you get it updated, otherwise you get
2147          * stuck with the static values. Since "EU" is not a valid
2148          * ISO / IEC 3166 alpha2 code we can't expect userpace to
2149          * give us a regulatory domain for it. We need last_request
2150          * iniitalized though so lets just send a request which we
2151          * know will be ignored... this crap will be removed once
2152          * OLD_REG dies.
2153          */
2154         err = regulatory_hint_core(ieee80211_regdom);
2155 #else
2156         cfg80211_regdomain = cfg80211_world_regdom;
2157
2158         err = regulatory_hint_core(ieee80211_regdom);
2159 #endif
2160         if (err) {
2161                 if (err == -ENOMEM)
2162                         return err;
2163                 /*
2164                  * N.B. kobject_uevent_env() can fail mainly for when we're out
2165                  * memory which is handled and propagated appropriately above
2166                  * but it can also fail during a netlink_broadcast() or during
2167                  * early boot for call_usermodehelper(). For now treat these
2168                  * errors as non-fatal.
2169                  */
2170                 printk(KERN_ERR "cfg80211: kobject_uevent_env() was unable "
2171                         "to call CRDA during init");
2172 #ifdef CONFIG_CFG80211_REG_DEBUG
2173                 /* We want to find out exactly why when debugging */
2174                 WARN_ON(err);
2175 #endif
2176         }
2177
2178         return 0;
2179 }
2180
2181 void regulatory_exit(void)
2182 {
2183         struct regulatory_request *reg_request, *tmp;
2184         struct reg_beacon *reg_beacon, *btmp;
2185
2186         cancel_work_sync(&reg_work);
2187
2188         mutex_lock(&cfg80211_mutex);
2189
2190         reset_regdomains();
2191
2192         kfree(country_ie_regdomain);
2193         country_ie_regdomain = NULL;
2194
2195         kfree(last_request);
2196
2197         platform_device_unregister(reg_pdev);
2198
2199         spin_lock_bh(&reg_pending_beacons_lock);
2200         if (!list_empty(&reg_pending_beacons)) {
2201                 list_for_each_entry_safe(reg_beacon, btmp,
2202                                          &reg_pending_beacons, list) {
2203                         list_del(&reg_beacon->list);
2204                         kfree(reg_beacon);
2205                 }
2206         }
2207         spin_unlock_bh(&reg_pending_beacons_lock);
2208
2209         if (!list_empty(&reg_beacon_list)) {
2210                 list_for_each_entry_safe(reg_beacon, btmp,
2211                                          &reg_beacon_list, list) {
2212                         list_del(&reg_beacon->list);
2213                         kfree(reg_beacon);
2214                 }
2215         }
2216
2217         spin_lock(&reg_requests_lock);
2218         if (!list_empty(&reg_requests_list)) {
2219                 list_for_each_entry_safe(reg_request, tmp,
2220                                          &reg_requests_list, list) {
2221                         list_del(&reg_request->list);
2222                         kfree(reg_request);
2223                 }
2224         }
2225         spin_unlock(&reg_requests_lock);
2226
2227         mutex_unlock(&cfg80211_mutex);
2228 }