net/mac80211/key.c

   1 /*
   2  * Copyright 2002-2005, Instant802 Networks, Inc.
   3  * Copyright 2005-2006, Devicescape Software, Inc.
   4  * Copyright 2006-2007  Jiri Benc <jbenc@suse.cz>
   5  * Copyright 2007-2008  Johannes Berg <johannes@sipsolutions.net>
   6  * Copyright 2013-2014  Intel Mobile Communications GmbH
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 as
  10  * published by the Free Software Foundation.
  11  */
  12
  13 #include <linux/if_ether.h>
  14 #include <linux/etherdevice.h>
  15 #include <linux/list.h>
  16 #include <linux/rcupdate.h>
  17 #include <linux/rtnetlink.h>
  18 #include <linux/slab.h>
  19 #include <linux/export.h>
  20 #include <net/mac80211.h>
  21 #include <asm/unaligned.h>
  22 #include "ieee80211_i.h"
  23 #include "driver-ops.h"
  24 #include "debugfs_key.h"
  25 #include "aes_ccm.h"
  26 #include "aes_cmac.h"
  27 #include "aes_gmac.h"
  28 #include "aes_gcm.h"
  29
  30
  31 /**
  32  * DOC: Key handling basics
  33  *
  34  * Key handling in mac80211 is done based on per-interface (sub_if_data)
  35  * keys and per-station keys. Since each station belongs to an interface,
  36  * each station key also belongs to that interface.
  37  *
  38  * Hardware acceleration is done on a best-effort basis for algorithms
  39  * that are implemented in software,  for each key the hardware is asked
  40  * to enable that key for offloading but if it cannot do that the key is
  41  * simply kept for software encryption (unless it is for an algorithm
  42  * that isn't implemented in software).
  43  * There is currently no way of knowing whether a key is handled in SW
  44  * or HW except by looking into debugfs.
  45  *
  46  * All key management is internally protected by a mutex. Within all
  47  * other parts of mac80211, key references are, just as STA structure
  48  * references, protected by RCU. Note, however, that some things are
  49  * unprotected, namely the key->sta dereferences within the hardware
  50  * acceleration functions. This means that sta_info_destroy() must
  51  * remove the key which waits for an RCU grace period.
  52  */
  53
  54 static const u8 bcast_addr[ETH_ALEN] = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF };
  55
  56 static void assert_key_lock(struct ieee80211_local *local)
  57 {
  58         lockdep_assert_held(&local->key_mtx);
  59 }
  60
  61 static void increment_tailroom_need_count(struct ieee80211_sub_if_data *sdata)
  62 {
  63         /*
  64          * When this count is zero, SKB resizing for allocating tailroom
  65          * for IV or MMIC is skipped. But, this check has created two race
  66          * cases in xmit path while transiting from zero count to one:
  67          *
  68          * 1. SKB resize was skipped because no key was added but just before
  69          * the xmit key is added and SW encryption kicks off.
  70          *
  71          * 2. SKB resize was skipped because all the keys were hw planted but
  72          * just before xmit one of the key is deleted and SW encryption kicks
  73          * off.
  74          *
  75          * In both the above case SW encryption will find not enough space for
  76          * tailroom and exits with WARN_ON. (See WARN_ONs at wpa.c)
  77          *
  78          * Solution has been explained at
  79          * http://mid.gmane.org/1308590980.4322.19.camel@jlt3.sipsolutions.net
  80          */
  81
  82         if (!sdata->crypto_tx_tailroom_needed_cnt++) {
  83                 /*
  84                  * Flush all XMIT packets currently using HW encryption or no
  85                  * encryption at all if the count transition is from 0 -> 1.
  86                  */
  87                 synchronize_net();
  88         }
  89 }
  90
  91 static int ieee80211_key_enable_hw_accel(struct ieee80211_key *key)
  92 {
  93         struct ieee80211_sub_if_data *sdata;
  94         struct sta_info *sta;
  95         int ret = -EOPNOTSUPP;
  96
  97         might_sleep();
  98
  99         if (key->flags & KEY_FLAG_TAINTED) {
 100                 /* If we get here, it's during resume and the key is
 101                  * tainted so shouldn't be used/programmed any more.
 102                  * However, its flags may still indicate that it was
 103                  * programmed into the device (since we're in resume)
 104                  * so clear that flag now to avoid trying to remove
 105                  * it again later.
 106                  */
 107                 key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;
 108                 return -EINVAL;
 109         }
 110
 111         if (!key->local->ops->set_key)
 112                 goto out_unsupported;
 113
 114         assert_key_lock(key->local);
 115
 116         sta = key->sta;
 117
 118         /*
 119          * If this is a per-STA GTK, check if it
 120          * is supported; if not, return.
 121          */
 122         if (sta && !(key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE) &&
 123             !(key->local->hw.flags & IEEE80211_HW_SUPPORTS_PER_STA_GTK))
 124                 goto out_unsupported;
 125
 126         if (sta && !sta->uploaded)
 127                 goto out_unsupported;
 128
 129         sdata = key->sdata;
 130         if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
 131                 /*
 132                  * The driver doesn't know anything about VLAN interfaces.
 133                  * Hence, don't send GTKs for VLAN interfaces to the driver.
 134                  */
 135                 if (!(key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE))
 136                         goto out_unsupported;
 137         }
 138
 139         ret = drv_set_key(key->local, SET_KEY, sdata,
 140                           sta ? &sta->sta : NULL, &key->conf);
 141
 142         if (!ret) {
 143                 key->flags |= KEY_FLAG_UPLOADED_TO_HARDWARE;
 144
 145                 if (!((key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC) ||
 146                       (key->conf.flags & IEEE80211_KEY_FLAG_RESERVE_TAILROOM)))
 147                         sdata->crypto_tx_tailroom_needed_cnt--;
 148
 149                 WARN_ON((key->conf.flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) &&
 150                         (key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV));
 151
 152                 return 0;
 153         }
 154
 155         if (ret != -ENOSPC && ret != -EOPNOTSUPP && ret != 1)
 156                 sdata_err(sdata,
 157                           "failed to set key (%d, %pM) to hardware (%d)\n",
 158                           key->conf.keyidx,
 159                           sta ? sta->sta.addr : bcast_addr, ret);
 160
 161  out_unsupported:
 162         switch (key->conf.cipher) {
 163         case WLAN_CIPHER_SUITE_WEP40:
 164         case WLAN_CIPHER_SUITE_WEP104:
 165         case WLAN_CIPHER_SUITE_TKIP:
 166         case WLAN_CIPHER_SUITE_CCMP:
 167         case WLAN_CIPHER_SUITE_CCMP_256:
 168         case WLAN_CIPHER_SUITE_AES_CMAC:
 169         case WLAN_CIPHER_SUITE_BIP_CMAC_256:
 170         case WLAN_CIPHER_SUITE_BIP_GMAC_128:
 171         case WLAN_CIPHER_SUITE_BIP_GMAC_256:
 172         case WLAN_CIPHER_SUITE_GCMP:
 173         case WLAN_CIPHER_SUITE_GCMP_256:
 174                 /* all of these we can do in software - if driver can */
 175                 if (ret == 1)
 176                         return 0;
 177                 if (key->local->hw.flags & IEEE80211_HW_SW_CRYPTO_CONTROL)
 178                         return -EINVAL;
 179                 return 0;
 180         default:
 181                 return -EINVAL;
 182         }
 183 }
 184
 185 static void ieee80211_key_disable_hw_accel(struct ieee80211_key *key)
 186 {
 187         struct ieee80211_sub_if_data *sdata;
 188         struct sta_info *sta;
 189         int ret;
 190
 191         might_sleep();
 192
 193         if (!key || !key->local->ops->set_key)
 194                 return;
 195
 196         assert_key_lock(key->local);
 197
 198         if (!(key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))
 199                 return;
 200
 201         sta = key->sta;
 202         sdata = key->sdata;
 203
 204         if (!((key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC) ||
 205               (key->conf.flags & IEEE80211_KEY_FLAG_RESERVE_TAILROOM)))
 206                 increment_tailroom_need_count(sdata);
 207
 208         ret = drv_set_key(key->local, DISABLE_KEY, sdata,
 209                           sta ? &sta->sta : NULL, &key->conf);
 210
 211         if (ret)
 212                 sdata_err(sdata,
 213                           "failed to remove key (%d, %pM) from hardware (%d)\n",
 214                           key->conf.keyidx,
 215                           sta ? sta->sta.addr : bcast_addr, ret);
 216
 217         key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;
 218 }
 219
 220 static void __ieee80211_set_default_key(struct ieee80211_sub_if_data *sdata,
 221                                         int idx, bool uni, bool multi)
 222 {
 223         struct ieee80211_key *key = NULL;
 224
 225         assert_key_lock(sdata->local);
 226
 227         if (idx >= 0 && idx < NUM_DEFAULT_KEYS)
 228                 key = key_mtx_dereference(sdata->local, sdata->keys[idx]);
 229
 230         if (uni) {
 231                 rcu_assign_pointer(sdata->default_unicast_key, key);
 232                 ieee80211_check_fast_xmit_iface(sdata);
 233                 drv_set_default_unicast_key(sdata->local, sdata, idx);
 234         }
 235
 236         if (multi)
 237                 rcu_assign_pointer(sdata->default_multicast_key, key);
 238
 239         ieee80211_debugfs_key_update_default(sdata);
 240 }
 241
 242 void ieee80211_set_default_key(struct ieee80211_sub_if_data *sdata, int idx,
 243                                bool uni, bool multi)
 244 {
 245         mutex_lock(&sdata->local->key_mtx);
 246         __ieee80211_set_default_key(sdata, idx, uni, multi);
 247         mutex_unlock(&sdata->local->key_mtx);
 248 }
 249
 250 static void
 251 __ieee80211_set_default_mgmt_key(struct ieee80211_sub_if_data *sdata, int idx)
 252 {
 253         struct ieee80211_key *key = NULL;
 254
 255         assert_key_lock(sdata->local);
 256
 257         if (idx >= NUM_DEFAULT_KEYS &&
 258             idx < NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
 259                 key = key_mtx_dereference(sdata->local, sdata->keys[idx]);
 260
 261         rcu_assign_pointer(sdata->default_mgmt_key, key);
 262
 263         ieee80211_debugfs_key_update_default(sdata);
 264 }
 265
 266 void ieee80211_set_default_mgmt_key(struct ieee80211_sub_if_data *sdata,
 267                                     int idx)
 268 {
 269         mutex_lock(&sdata->local->key_mtx);
 270         __ieee80211_set_default_mgmt_key(sdata, idx);
 271         mutex_unlock(&sdata->local->key_mtx);
 272 }
 273
 274
 275 static void ieee80211_key_replace(struct ieee80211_sub_if_data *sdata,
 276                                   struct sta_info *sta,
 277                                   bool pairwise,
 278                                   struct ieee80211_key *old,
 279                                   struct ieee80211_key *new)
 280 {
 281         int idx;
 282         bool defunikey, defmultikey, defmgmtkey;
 283
 284         /* caller must provide at least one old/new */
 285         if (WARN_ON(!new && !old))
 286                 return;
 287
 288         if (new)
 289                 list_add_tail(&new->list, &sdata->key_list);
 290
 291         WARN_ON(new && old && new->conf.keyidx != old->conf.keyidx);
 292
 293         if (old)
 294                 idx = old->conf.keyidx;
 295         else
 296                 idx = new->conf.keyidx;
 297
 298         if (sta) {
 299                 if (pairwise) {
 300                         rcu_assign_pointer(sta->ptk[idx], new);
 301                         sta->ptk_idx = idx;
 302                         ieee80211_check_fast_xmit(sta);
 303                 } else {
 304                         rcu_assign_pointer(sta->gtk[idx], new);
 305                         sta->gtk_idx = idx;
 306                 }
 307         } else {
 308                 defunikey = old &&
 309                         old == key_mtx_dereference(sdata->local,
 310                                                 sdata->default_unicast_key);
 311                 defmultikey = old &&
 312                         old == key_mtx_dereference(sdata->local,
 313                                                 sdata->default_multicast_key);
 314                 defmgmtkey = old &&
 315                         old == key_mtx_dereference(sdata->local,
 316                                                 sdata->default_mgmt_key);
 317
 318                 if (defunikey && !new)
 319                         __ieee80211_set_default_key(sdata, -1, true, false);
 320                 if (defmultikey && !new)
 321                         __ieee80211_set_default_key(sdata, -1, false, true);
 322                 if (defmgmtkey && !new)
 323                         __ieee80211_set_default_mgmt_key(sdata, -1);
 324
 325                 rcu_assign_pointer(sdata->keys[idx], new);
 326                 if (defunikey && new)
 327                         __ieee80211_set_default_key(sdata, new->conf.keyidx,
 328                                                     true, false);
 329                 if (defmultikey && new)
 330                         __ieee80211_set_default_key(sdata, new->conf.keyidx,
 331                                                     false, true);
 332                 if (defmgmtkey && new)
 333                         __ieee80211_set_default_mgmt_key(sdata,
 334                                                          new->conf.keyidx);
 335         }
 336
 337         if (old)
 338                 list_del(&old->list);
 339 }
 340
 341 struct ieee80211_key *
 342 ieee80211_key_alloc(u32 cipher, int idx, size_t key_len,
 343                     const u8 *key_data,
 344                     size_t seq_len, const u8 *seq,
 345                     const struct ieee80211_cipher_scheme *cs)
 346 {
 347         struct ieee80211_key *key;
 348         int i, j, err;
 349
 350         if (WARN_ON(idx < 0 || idx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS))
 351                 return ERR_PTR(-EINVAL);
 352
 353         key = kzalloc(sizeof(struct ieee80211_key) + key_len, GFP_KERNEL);
 354         if (!key)
 355                 return ERR_PTR(-ENOMEM);
 356
 357         /*
 358          * Default to software encryption; we'll later upload the
 359          * key to the hardware if possible.
 360          */
 361         key->conf.flags = 0;
 362         key->flags = 0;
 363
 364         key->conf.cipher = cipher;
 365         key->conf.keyidx = idx;
 366         key->conf.keylen = key_len;
 367         switch (cipher) {
 368         case WLAN_CIPHER_SUITE_WEP40:
 369         case WLAN_CIPHER_SUITE_WEP104:
 370                 key->conf.iv_len = IEEE80211_WEP_IV_LEN;
 371                 key->conf.icv_len = IEEE80211_WEP_ICV_LEN;
 372                 break;
 373         case WLAN_CIPHER_SUITE_TKIP:
 374                 key->conf.iv_len = IEEE80211_TKIP_IV_LEN;
 375                 key->conf.icv_len = IEEE80211_TKIP_ICV_LEN;
 376                 if (seq) {
 377                         for (i = 0; i < IEEE80211_NUM_TIDS; i++) {
 378                                 key->u.tkip.rx[i].iv32 =
 379                                         get_unaligned_le32(&seq[2]);
 380                                 key->u.tkip.rx[i].iv16 =
 381                                         get_unaligned_le16(seq);
 382                         }
 383                 }
 384                 spin_lock_init(&key->u.tkip.txlock);
 385                 break;
 386         case WLAN_CIPHER_SUITE_CCMP:
 387                 key->conf.iv_len = IEEE80211_CCMP_HDR_LEN;
 388                 key->conf.icv_len = IEEE80211_CCMP_MIC_LEN;
 389                 if (seq) {
 390                         for (i = 0; i < IEEE80211_NUM_TIDS + 1; i++)
 391                                 for (j = 0; j < IEEE80211_CCMP_PN_LEN; j++)
 392                                         key->u.ccmp.rx_pn[i][j] =
 393                                                 seq[IEEE80211_CCMP_PN_LEN - j - 1];
 394                 }
 395                 /*
 396                  * Initialize AES key state here as an optimization so that
 397                  * it does not need to be initialized for every packet.
 398                  */
 399                 key->u.ccmp.tfm = ieee80211_aes_key_setup_encrypt(
 400                         key_data, key_len, IEEE80211_CCMP_MIC_LEN);
 401                 if (IS_ERR(key->u.ccmp.tfm)) {
 402                         err = PTR_ERR(key->u.ccmp.tfm);
 403                         kfree(key);
 404                         return ERR_PTR(err);
 405                 }
 406                 break;
 407         case WLAN_CIPHER_SUITE_CCMP_256:
 408                 key->conf.iv_len = IEEE80211_CCMP_256_HDR_LEN;
 409                 key->conf.icv_len = IEEE80211_CCMP_256_MIC_LEN;
 410                 for (i = 0; seq && i < IEEE80211_NUM_TIDS + 1; i++)
 411                         for (j = 0; j < IEEE80211_CCMP_256_PN_LEN; j++)
 412                                 key->u.ccmp.rx_pn[i][j] =
 413                                         seq[IEEE80211_CCMP_256_PN_LEN - j - 1];
 414                 /* Initialize AES key state here as an optimization so that
 415                  * it does not need to be initialized for every packet.
 416                  */
 417                 key->u.ccmp.tfm = ieee80211_aes_key_setup_encrypt(
 418                         key_data, key_len, IEEE80211_CCMP_256_MIC_LEN);
 419                 if (IS_ERR(key->u.ccmp.tfm)) {
 420                         err = PTR_ERR(key->u.ccmp.tfm);
 421                         kfree(key);
 422                         return ERR_PTR(err);
 423                 }
 424                 break;
 425         case WLAN_CIPHER_SUITE_AES_CMAC:
 426         case WLAN_CIPHER_SUITE_BIP_CMAC_256:
 427                 key->conf.iv_len = 0;
 428                 if (cipher == WLAN_CIPHER_SUITE_AES_CMAC)
 429                         key->conf.icv_len = sizeof(struct ieee80211_mmie);
 430                 else
 431                         key->conf.icv_len = sizeof(struct ieee80211_mmie_16);
 432                 if (seq)
 433                         for (j = 0; j < IEEE80211_CMAC_PN_LEN; j++)
 434                                 key->u.aes_cmac.rx_pn[j] =
 435                                         seq[IEEE80211_CMAC_PN_LEN - j - 1];
 436                 /*
 437                  * Initialize AES key state here as an optimization so that
 438                  * it does not need to be initialized for every packet.
 439                  */
 440                 key->u.aes_cmac.tfm =
 441                         ieee80211_aes_cmac_key_setup(key_data, key_len);
 442                 if (IS_ERR(key->u.aes_cmac.tfm)) {
 443                         err = PTR_ERR(key->u.aes_cmac.tfm);
 444                         kfree(key);
 445                         return ERR_PTR(err);
 446                 }
 447                 break;
 448         case WLAN_CIPHER_SUITE_BIP_GMAC_128:
 449         case WLAN_CIPHER_SUITE_BIP_GMAC_256:
 450                 key->conf.iv_len = 0;
 451                 key->conf.icv_len = sizeof(struct ieee80211_mmie_16);
 452                 if (seq)
 453                         for (j = 0; j < IEEE80211_GMAC_PN_LEN; j++)
 454                                 key->u.aes_gmac.rx_pn[j] =
 455                                         seq[IEEE80211_GMAC_PN_LEN - j - 1];
 456                 /* Initialize AES key state here as an optimization so that
 457                  * it does not need to be initialized for every packet.
 458                  */
 459                 key->u.aes_gmac.tfm =
 460                         ieee80211_aes_gmac_key_setup(key_data, key_len);
 461                 if (IS_ERR(key->u.aes_gmac.tfm)) {
 462                         err = PTR_ERR(key->u.aes_gmac.tfm);
 463                         kfree(key);
 464                         return ERR_PTR(err);
 465                 }
 466                 break;
 467         case WLAN_CIPHER_SUITE_GCMP:
 468         case WLAN_CIPHER_SUITE_GCMP_256:
 469                 key->conf.iv_len = IEEE80211_GCMP_HDR_LEN;
 470                 key->conf.icv_len = IEEE80211_GCMP_MIC_LEN;
 471                 for (i = 0; seq && i < IEEE80211_NUM_TIDS + 1; i++)
 472                         for (j = 0; j < IEEE80211_GCMP_PN_LEN; j++)
 473                                 key->u.gcmp.rx_pn[i][j] =
 474                                         seq[IEEE80211_GCMP_PN_LEN - j - 1];
 475                 /* Initialize AES key state here as an optimization so that
 476                  * it does not need to be initialized for every packet.
 477                  */
 478                 key->u.gcmp.tfm = ieee80211_aes_gcm_key_setup_encrypt(key_data,
 479                                                                       key_len);
 480                 if (IS_ERR(key->u.gcmp.tfm)) {
 481                         err = PTR_ERR(key->u.gcmp.tfm);
 482                         kfree(key);
 483                         return ERR_PTR(err);
 484                 }
 485                 break;
 486         default:
 487                 if (cs) {
 488                         if (seq_len && seq_len != cs->pn_len) {
 489                                 kfree(key);
 490                                 return ERR_PTR(-EINVAL);
 491                         }
 492
 493                         key->conf.iv_len = cs->hdr_len;
 494                         key->conf.icv_len = cs->mic_len;
 495                         for (i = 0; i < IEEE80211_NUM_TIDS + 1; i++)
 496                                 for (j = 0; j < seq_len; j++)
 497                                         key->u.gen.rx_pn[i][j] =
 498                                                         seq[seq_len - j - 1];
 499                         key->flags |= KEY_FLAG_CIPHER_SCHEME;
 500                 }
 501         }
 502         memcpy(key->conf.key, key_data, key_len);
 503         INIT_LIST_HEAD(&key->list);
 504
 505         return key;
 506 }
 507
 508 static void ieee80211_key_free_common(struct ieee80211_key *key)
 509 {
 510         switch (key->conf.cipher) {
 511         case WLAN_CIPHER_SUITE_CCMP:
 512         case WLAN_CIPHER_SUITE_CCMP_256:
 513                 ieee80211_aes_key_free(key->u.ccmp.tfm);
 514                 break;
 515         case WLAN_CIPHER_SUITE_AES_CMAC:
 516         case WLAN_CIPHER_SUITE_BIP_CMAC_256:
 517                 ieee80211_aes_cmac_key_free(key->u.aes_cmac.tfm);
 518                 break;
 519         case WLAN_CIPHER_SUITE_BIP_GMAC_128:
 520         case WLAN_CIPHER_SUITE_BIP_GMAC_256:
 521                 ieee80211_aes_gmac_key_free(key->u.aes_gmac.tfm);
 522                 break;
 523         case WLAN_CIPHER_SUITE_GCMP:
 524         case WLAN_CIPHER_SUITE_GCMP_256:
 525                 ieee80211_aes_gcm_key_free(key->u.gcmp.tfm);
 526                 break;
 527         }
 528         kzfree(key);
 529 }
 530
 531 static void __ieee80211_key_destroy(struct ieee80211_key *key,
 532                                     bool delay_tailroom)
 533 {
 534         if (key->local)
 535                 ieee80211_key_disable_hw_accel(key);
 536
 537         if (key->local) {
 538                 struct ieee80211_sub_if_data *sdata = key->sdata;
 539
 540                 ieee80211_debugfs_key_remove(key);
 541
 542                 if (delay_tailroom) {
 543                         /* see ieee80211_delayed_tailroom_dec */
 544                         sdata->crypto_tx_tailroom_pending_dec++;
 545                         schedule_delayed_work(&sdata->dec_tailroom_needed_wk,
 546                                               HZ/2);
 547                 } else {
 548                         sdata->crypto_tx_tailroom_needed_cnt--;
 549                 }
 550         }
 551
 552         ieee80211_key_free_common(key);
 553 }
 554
 555 static void ieee80211_key_destroy(struct ieee80211_key *key,
 556                                   bool delay_tailroom)
 557 {
 558         if (!key)
 559                 return;
 560
 561         /*
 562          * Synchronize so the TX path can no longer be using
 563          * this key before we free/remove it.
 564          */
 565         synchronize_net();
 566
 567         __ieee80211_key_destroy(key, delay_tailroom);
 568 }
 569
 570 void ieee80211_key_free_unused(struct ieee80211_key *key)
 571 {
 572         WARN_ON(key->sdata || key->local);
 573         ieee80211_key_free_common(key);
 574 }
 575
 576 int ieee80211_key_link(struct ieee80211_key *key,
 577                        struct ieee80211_sub_if_data *sdata,
 578                        struct sta_info *sta)
 579 {
 580         struct ieee80211_local *local = sdata->local;
 581         struct ieee80211_key *old_key;
 582         int idx, ret;
 583         bool pairwise;
 584
 585         pairwise = key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE;
 586         idx = key->conf.keyidx;
 587         key->local = sdata->local;
 588         key->sdata = sdata;
 589         key->sta = sta;
 590
 591         mutex_lock(&sdata->local->key_mtx);
 592
 593         if (sta && pairwise)
 594                 old_key = key_mtx_dereference(sdata->local, sta->ptk[idx]);
 595         else if (sta)
 596                 old_key = key_mtx_dereference(sdata->local, sta->gtk[idx]);
 597         else
 598                 old_key = key_mtx_dereference(sdata->local, sdata->keys[idx]);
 599
 600         increment_tailroom_need_count(sdata);
 601
 602         ieee80211_key_replace(sdata, sta, pairwise, old_key, key);
 603         ieee80211_key_destroy(old_key, true);
 604
 605         ieee80211_debugfs_key_add(key);
 606
 607         if (!local->wowlan) {
 608                 ret = ieee80211_key_enable_hw_accel(key);
 609                 if (ret)
 610                         ieee80211_key_free(key, true);
 611         } else {
 612                 ret = 0;
 613         }
 614
 615         mutex_unlock(&sdata->local->key_mtx);
 616
 617         return ret;
 618 }
 619
 620 void ieee80211_key_free(struct ieee80211_key *key, bool delay_tailroom)
 621 {
 622         if (!key)
 623                 return;
 624
 625         /*
 626          * Replace key with nothingness if it was ever used.
 627          */
 628         if (key->sdata)
 629                 ieee80211_key_replace(key->sdata, key->sta,
 630                                 key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
 631                                 key, NULL);
 632         ieee80211_key_destroy(key, delay_tailroom);
 633 }
 634
 635 void ieee80211_enable_keys(struct ieee80211_sub_if_data *sdata)
 636 {
 637         struct ieee80211_key *key;
 638
 639         ASSERT_RTNL();
 640
 641         if (WARN_ON(!ieee80211_sdata_running(sdata)))
 642                 return;
 643
 644         mutex_lock(&sdata->local->key_mtx);
 645
 646         sdata->crypto_tx_tailroom_needed_cnt = 0;
 647
 648         list_for_each_entry(key, &sdata->key_list, list) {
 649                 increment_tailroom_need_count(sdata);
 650                 ieee80211_key_enable_hw_accel(key);
 651         }
 652
 653         mutex_unlock(&sdata->local->key_mtx);
 654 }
 655
 656 void ieee80211_iter_keys(struct ieee80211_hw *hw,
 657                          struct ieee80211_vif *vif,
 658                          void (*iter)(struct ieee80211_hw *hw,
 659                                       struct ieee80211_vif *vif,
 660                                       struct ieee80211_sta *sta,
 661                                       struct ieee80211_key_conf *key,
 662                                       void *data),
 663                          void *iter_data)
 664 {
 665         struct ieee80211_local *local = hw_to_local(hw);
 666         struct ieee80211_key *key, *tmp;
 667         struct ieee80211_sub_if_data *sdata;
 668
 669         ASSERT_RTNL();
 670
 671         mutex_lock(&local->key_mtx);
 672         if (vif) {
 673                 sdata = vif_to_sdata(vif);
 674                 list_for_each_entry_safe(key, tmp, &sdata->key_list, list)
 675                         iter(hw, &sdata->vif,
 676                              key->sta ? &key->sta->sta : NULL,
 677                              &key->conf, iter_data);
 678         } else {
 679                 list_for_each_entry(sdata, &local->interfaces, list)
 680                         list_for_each_entry_safe(key, tmp,
 681                                                  &sdata->key_list, list)
 682                                 iter(hw, &sdata->vif,
 683                                      key->sta ? &key->sta->sta : NULL,
 684                                      &key->conf, iter_data);
 685         }
 686         mutex_unlock(&local->key_mtx);
 687 }
 688 EXPORT_SYMBOL(ieee80211_iter_keys);
 689
 690 static void ieee80211_free_keys_iface(struct ieee80211_sub_if_data *sdata,
 691                                       struct list_head *keys)
 692 {
 693         struct ieee80211_key *key, *tmp;
 694
 695         sdata->crypto_tx_tailroom_needed_cnt -=
 696                 sdata->crypto_tx_tailroom_pending_dec;
 697         sdata->crypto_tx_tailroom_pending_dec = 0;
 698
 699         ieee80211_debugfs_key_remove_mgmt_default(sdata);
 700
 701         list_for_each_entry_safe(key, tmp, &sdata->key_list, list) {
 702                 ieee80211_key_replace(key->sdata, key->sta,
 703                                 key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
 704                                 key, NULL);
 705                 list_add_tail(&key->list, keys);
 706         }
 707
 708         ieee80211_debugfs_key_update_default(sdata);
 709 }
 710
 711 void ieee80211_free_keys(struct ieee80211_sub_if_data *sdata,
 712                          bool force_synchronize)
 713 {
 714         struct ieee80211_local *local = sdata->local;
 715         struct ieee80211_sub_if_data *vlan;
 716         struct ieee80211_key *key, *tmp;
 717         LIST_HEAD(keys);
 718
 719         cancel_delayed_work_sync(&sdata->dec_tailroom_needed_wk);
 720
 721         mutex_lock(&local->key_mtx);
 722
 723         ieee80211_free_keys_iface(sdata, &keys);
 724
 725         if (sdata->vif.type == NL80211_IFTYPE_AP) {
 726                 list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
 727                         ieee80211_free_keys_iface(vlan, &keys);
 728         }
 729
 730         if (!list_empty(&keys) || force_synchronize)
 731                 synchronize_net();
 732         list_for_each_entry_safe(key, tmp, &keys, list)
 733                 __ieee80211_key_destroy(key, false);
 734
 735         WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt ||
 736                      sdata->crypto_tx_tailroom_pending_dec);
 737         if (sdata->vif.type == NL80211_IFTYPE_AP) {
 738                 list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
 739                         WARN_ON_ONCE(vlan->crypto_tx_tailroom_needed_cnt ||
 740                                      vlan->crypto_tx_tailroom_pending_dec);
 741         }
 742
 743         mutex_unlock(&local->key_mtx);
 744 }
 745
 746 void ieee80211_free_sta_keys(struct ieee80211_local *local,
 747                              struct sta_info *sta)
 748 {
 749         struct ieee80211_key *key;
 750         int i;
 751
 752         mutex_lock(&local->key_mtx);
 753         for (i = 0; i < ARRAY_SIZE(sta->gtk); i++) {
 754                 key = key_mtx_dereference(local, sta->gtk[i]);
 755                 if (!key)
 756                         continue;
 757                 ieee80211_key_replace(key->sdata, key->sta,
 758                                 key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
 759                                 key, NULL);
 760                 __ieee80211_key_destroy(key, true);
 761         }
 762
 763         for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
 764                 key = key_mtx_dereference(local, sta->ptk[i]);
 765                 if (!key)
 766                         continue;
 767                 ieee80211_key_replace(key->sdata, key->sta,
 768                                 key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
 769                                 key, NULL);
 770                 __ieee80211_key_destroy(key, true);
 771         }
 772
 773         mutex_unlock(&local->key_mtx);
 774 }
 775
 776 void ieee80211_delayed_tailroom_dec(struct work_struct *wk)
 777 {
 778         struct ieee80211_sub_if_data *sdata;
 779
 780         sdata = container_of(wk, struct ieee80211_sub_if_data,
 781                              dec_tailroom_needed_wk.work);
 782
 783         /*
 784          * The reason for the delayed tailroom needed decrementing is to
 785          * make roaming faster: during roaming, all keys are first deleted
 786          * and then new keys are installed. The first new key causes the
 787          * crypto_tx_tailroom_needed_cnt to go from 0 to 1, which invokes
 788          * the cost of synchronize_net() (which can be slow). Avoid this
 789          * by deferring the crypto_tx_tailroom_needed_cnt decrementing on
 790          * key removal for a while, so if we roam the value is larger than
 791          * zero and no 0->1 transition happens.
 792          *
 793          * The cost is that if the AP switching was from an AP with keys
 794          * to one without, we still allocate tailroom while it would no
 795          * longer be needed. However, in the typical (fast) roaming case
 796          * within an ESS this usually won't happen.
 797          */
 798
 799         mutex_lock(&sdata->local->key_mtx);
 800         sdata->crypto_tx_tailroom_needed_cnt -=
 801                 sdata->crypto_tx_tailroom_pending_dec;
 802         sdata->crypto_tx_tailroom_pending_dec = 0;
 803         mutex_unlock(&sdata->local->key_mtx);
 804 }
 805
 806 void ieee80211_gtk_rekey_notify(struct ieee80211_vif *vif, const u8 *bssid,
 807                                 const u8 *replay_ctr, gfp_t gfp)
 808 {
 809         struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
 810
 811         trace_api_gtk_rekey_notify(sdata, bssid, replay_ctr);
 812
 813         cfg80211_gtk_rekey_notify(sdata->dev, bssid, replay_ctr, gfp);
 814 }
 815 EXPORT_SYMBOL_GPL(ieee80211_gtk_rekey_notify);
 816
 817 void ieee80211_get_key_tx_seq(struct ieee80211_key_conf *keyconf,
 818                               struct ieee80211_key_seq *seq)
 819 {
 820         struct ieee80211_key *key;
 821         u64 pn64;
 822
 823         if (WARN_ON(!(keyconf->flags & IEEE80211_KEY_FLAG_GENERATE_IV)))
 824                 return;
 825
 826         key = container_of(keyconf, struct ieee80211_key, conf);
 827
 828         switch (key->conf.cipher) {
 829         case WLAN_CIPHER_SUITE_TKIP:
 830                 seq->tkip.iv32 = key->u.tkip.tx.iv32;
 831                 seq->tkip.iv16 = key->u.tkip.tx.iv16;
 832                 break;
 833         case WLAN_CIPHER_SUITE_CCMP:
 834         case WLAN_CIPHER_SUITE_CCMP_256:
 835         case WLAN_CIPHER_SUITE_AES_CMAC:
 836         case WLAN_CIPHER_SUITE_BIP_CMAC_256:
 837                 BUILD_BUG_ON(offsetof(typeof(*seq), ccmp) !=
 838                              offsetof(typeof(*seq), aes_cmac));
 839         case WLAN_CIPHER_SUITE_BIP_GMAC_128:
 840         case WLAN_CIPHER_SUITE_BIP_GMAC_256:
 841                 BUILD_BUG_ON(offsetof(typeof(*seq), ccmp) !=
 842                              offsetof(typeof(*seq), aes_gmac));
 843         case WLAN_CIPHER_SUITE_GCMP:
 844         case WLAN_CIPHER_SUITE_GCMP_256:
 845                 BUILD_BUG_ON(offsetof(typeof(*seq), ccmp) !=
 846                              offsetof(typeof(*seq), gcmp));
 847                 pn64 = atomic64_read(&key->conf.tx_pn);
 848                 seq->ccmp.pn[5] = pn64;
 849                 seq->ccmp.pn[4] = pn64 >> 8;
 850                 seq->ccmp.pn[3] = pn64 >> 16;
 851                 seq->ccmp.pn[2] = pn64 >> 24;
 852                 seq->ccmp.pn[1] = pn64 >> 32;
 853                 seq->ccmp.pn[0] = pn64 >> 40;
 854                 break;
 855         default:
 856                 WARN_ON(1);
 857         }
 858 }
 859 EXPORT_SYMBOL(ieee80211_get_key_tx_seq);
 860
 861 void ieee80211_get_key_rx_seq(struct ieee80211_key_conf *keyconf,
 862                               int tid, struct ieee80211_key_seq *seq)
 863 {
 864         struct ieee80211_key *key;
 865         const u8 *pn;
 866
 867         key = container_of(keyconf, struct ieee80211_key, conf);
 868
 869         switch (key->conf.cipher) {
 870         case WLAN_CIPHER_SUITE_TKIP:
 871                 if (WARN_ON(tid < 0 || tid >= IEEE80211_NUM_TIDS))
 872                         return;
 873                 seq->tkip.iv32 = key->u.tkip.rx[tid].iv32;
 874                 seq->tkip.iv16 = key->u.tkip.rx[tid].iv16;
 875                 break;
 876         case WLAN_CIPHER_SUITE_CCMP:
 877         case WLAN_CIPHER_SUITE_CCMP_256:
 878                 if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
 879                         return;
 880                 if (tid < 0)
 881                         pn = key->u.ccmp.rx_pn[IEEE80211_NUM_TIDS];
 882                 else
 883                         pn = key->u.ccmp.rx_pn[tid];
 884                 memcpy(seq->ccmp.pn, pn, IEEE80211_CCMP_PN_LEN);
 885                 break;
 886         case WLAN_CIPHER_SUITE_AES_CMAC:
 887         case WLAN_CIPHER_SUITE_BIP_CMAC_256:
 888                 if (WARN_ON(tid != 0))
 889                         return;
 890                 pn = key->u.aes_cmac.rx_pn;
 891                 memcpy(seq->aes_cmac.pn, pn, IEEE80211_CMAC_PN_LEN);
 892                 break;
 893         case WLAN_CIPHER_SUITE_BIP_GMAC_128:
 894         case WLAN_CIPHER_SUITE_BIP_GMAC_256:
 895                 if (WARN_ON(tid != 0))
 896                         return;
 897                 pn = key->u.aes_gmac.rx_pn;
 898                 memcpy(seq->aes_gmac.pn, pn, IEEE80211_GMAC_PN_LEN);
 899                 break;
 900         case WLAN_CIPHER_SUITE_GCMP:
 901         case WLAN_CIPHER_SUITE_GCMP_256:
 902                 if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
 903                         return;
 904                 if (tid < 0)
 905                         pn = key->u.gcmp.rx_pn[IEEE80211_NUM_TIDS];
 906                 else
 907                         pn = key->u.gcmp.rx_pn[tid];
 908                 memcpy(seq->gcmp.pn, pn, IEEE80211_GCMP_PN_LEN);
 909                 break;
 910         }
 911 }
 912 EXPORT_SYMBOL(ieee80211_get_key_rx_seq);
 913
 914 void ieee80211_set_key_tx_seq(struct ieee80211_key_conf *keyconf,
 915                               struct ieee80211_key_seq *seq)
 916 {
 917         struct ieee80211_key *key;
 918         u64 pn64;
 919
 920         key = container_of(keyconf, struct ieee80211_key, conf);
 921
 922         switch (key->conf.cipher) {
 923         case WLAN_CIPHER_SUITE_TKIP:
 924                 key->u.tkip.tx.iv32 = seq->tkip.iv32;
 925                 key->u.tkip.tx.iv16 = seq->tkip.iv16;
 926                 break;
 927         case WLAN_CIPHER_SUITE_CCMP:
 928         case WLAN_CIPHER_SUITE_CCMP_256:
 929         case WLAN_CIPHER_SUITE_AES_CMAC:
 930         case WLAN_CIPHER_SUITE_BIP_CMAC_256:
 931                 BUILD_BUG_ON(offsetof(typeof(*seq), ccmp) !=
 932                              offsetof(typeof(*seq), aes_cmac));
 933         case WLAN_CIPHER_SUITE_BIP_GMAC_128:
 934         case WLAN_CIPHER_SUITE_BIP_GMAC_256:
 935                 BUILD_BUG_ON(offsetof(typeof(*seq), ccmp) !=
 936                              offsetof(typeof(*seq), aes_gmac));
 937         case WLAN_CIPHER_SUITE_GCMP:
 938         case WLAN_CIPHER_SUITE_GCMP_256:
 939                 BUILD_BUG_ON(offsetof(typeof(*seq), ccmp) !=
 940                              offsetof(typeof(*seq), gcmp));
 941                 pn64 = (u64)seq->ccmp.pn[5] |
 942                        ((u64)seq->ccmp.pn[4] << 8) |
 943                        ((u64)seq->ccmp.pn[3] << 16) |
 944                        ((u64)seq->ccmp.pn[2] << 24) |
 945                        ((u64)seq->ccmp.pn[1] << 32) |
 946                        ((u64)seq->ccmp.pn[0] << 40);
 947                 atomic64_set(&key->conf.tx_pn, pn64);
 948                 break;
 949         default:
 950                 WARN_ON(1);
 951                 break;
 952         }
 953 }
 954 EXPORT_SYMBOL_GPL(ieee80211_set_key_tx_seq);
 955
 956 void ieee80211_set_key_rx_seq(struct ieee80211_key_conf *keyconf,
 957                               int tid, struct ieee80211_key_seq *seq)
 958 {
 959         struct ieee80211_key *key;
 960         u8 *pn;
 961
 962         key = container_of(keyconf, struct ieee80211_key, conf);
 963
 964         switch (key->conf.cipher) {
 965         case WLAN_CIPHER_SUITE_TKIP:
 966                 if (WARN_ON(tid < 0 || tid >= IEEE80211_NUM_TIDS))
 967                         return;
 968                 key->u.tkip.rx[tid].iv32 = seq->tkip.iv32;
 969                 key->u.tkip.rx[tid].iv16 = seq->tkip.iv16;
 970                 break;
 971         case WLAN_CIPHER_SUITE_CCMP:
 972         case WLAN_CIPHER_SUITE_CCMP_256:
 973                 if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
 974                         return;
 975                 if (tid < 0)
 976                         pn = key->u.ccmp.rx_pn[IEEE80211_NUM_TIDS];
 977                 else
 978                         pn = key->u.ccmp.rx_pn[tid];
 979                 memcpy(pn, seq->ccmp.pn, IEEE80211_CCMP_PN_LEN);
 980                 break;
 981         case WLAN_CIPHER_SUITE_AES_CMAC:
 982         case WLAN_CIPHER_SUITE_BIP_CMAC_256:
 983                 if (WARN_ON(tid != 0))
 984                         return;
 985                 pn = key->u.aes_cmac.rx_pn;
 986                 memcpy(pn, seq->aes_cmac.pn, IEEE80211_CMAC_PN_LEN);
 987                 break;
 988         case WLAN_CIPHER_SUITE_BIP_GMAC_128:
 989         case WLAN_CIPHER_SUITE_BIP_GMAC_256:
 990                 if (WARN_ON(tid != 0))
 991                         return;
 992                 pn = key->u.aes_gmac.rx_pn;
 993                 memcpy(pn, seq->aes_gmac.pn, IEEE80211_GMAC_PN_LEN);
 994                 break;
 995         case WLAN_CIPHER_SUITE_GCMP:
 996         case WLAN_CIPHER_SUITE_GCMP_256:
 997                 if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
 998                         return;
 999                 if (tid < 0)
1000                         pn = key->u.gcmp.rx_pn[IEEE80211_NUM_TIDS];
1001                 else
1002                         pn = key->u.gcmp.rx_pn[tid];
1003                 memcpy(pn, seq->gcmp.pn, IEEE80211_GCMP_PN_LEN);
1004                 break;
1005         default:
1006                 WARN_ON(1);
1007                 break;
1008         }
1009 }
1010 EXPORT_SYMBOL_GPL(ieee80211_set_key_rx_seq);
1011
1012 void ieee80211_remove_key(struct ieee80211_key_conf *keyconf)
1013 {
1014         struct ieee80211_key *key;
1015
1016         key = container_of(keyconf, struct ieee80211_key, conf);
1017
1018         assert_key_lock(key->local);
1019
1020         /*
1021          * if key was uploaded, we assume the driver will/has remove(d)
1022          * it, so adjust bookkeeping accordingly
1023          */
1024         if (key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) {
1025                 key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;
1026
1027                 if (!((key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC) ||
1028                       (key->conf.flags & IEEE80211_KEY_FLAG_RESERVE_TAILROOM)))
1029                         increment_tailroom_need_count(key->sdata);
1030         }
1031
1032         ieee80211_key_free(key, false);
1033 }
1034 EXPORT_SYMBOL_GPL(ieee80211_remove_key);
1035
1036 struct ieee80211_key_conf *
1037 ieee80211_gtk_rekey_add(struct ieee80211_vif *vif,
1038                         struct ieee80211_key_conf *keyconf)
1039 {
1040         struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
1041         struct ieee80211_local *local = sdata->local;
1042         struct ieee80211_key *key;
1043         int err;
1044
1045         if (WARN_ON(!local->wowlan))
1046                 return ERR_PTR(-EINVAL);
1047
1048         if (WARN_ON(vif->type != NL80211_IFTYPE_STATION))
1049                 return ERR_PTR(-EINVAL);
1050
1051         key = ieee80211_key_alloc(keyconf->cipher, keyconf->keyidx,
1052                                   keyconf->keylen, keyconf->key,
1053                                   0, NULL, NULL);
1054         if (IS_ERR(key))
1055                 return ERR_CAST(key);
1056
1057         if (sdata->u.mgd.mfp != IEEE80211_MFP_DISABLED)
1058                 key->conf.flags |= IEEE80211_KEY_FLAG_RX_MGMT;
1059
1060         err = ieee80211_key_link(key, sdata, NULL);
1061         if (err)
1062                 return ERR_PTR(err);
1063
1064         return &key->conf;
1065 }
1066 EXPORT_SYMBOL_GPL(ieee80211_gtk_rekey_add);