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