1 /* 2 * Copyright (c) 2008, 2009 open80211s Ltd. 3 * Author: Luis Carlos Cobo <luisca@cozybit.com> 4 * 5 * This program is free software; you can redistribute it and/or modify 6 * it under the terms of the GNU General Public License version 2 as 7 * published by the Free Software Foundation. 8 */ 9 #include <linux/gfp.h> 10 #include <linux/kernel.h> 11 #include <linux/random.h> 12 #include "ieee80211_i.h" 13 #include "rate.h" 14 #include "mesh.h" 15 16 #define PLINK_GET_LLID(p) (p + 2) 17 #define PLINK_GET_PLID(p) (p + 4) 18 19 #define mod_plink_timer(s, t) (mod_timer(&s->plink_timer, \ 20 jiffies + HZ * t / 1000)) 21 22 /* We only need a valid sta if user configured a minimum rssi_threshold. */ 23 #define rssi_threshold_check(sta, sdata) \ 24 (sdata->u.mesh.mshcfg.rssi_threshold == 0 ||\ 25 (sta && (s8) -ewma_read(&sta->avg_signal) > \ 26 sdata->u.mesh.mshcfg.rssi_threshold)) 27 28 enum plink_event { 29 PLINK_UNDEFINED, 30 OPN_ACPT, 31 OPN_RJCT, 32 OPN_IGNR, 33 CNF_ACPT, 34 CNF_RJCT, 35 CNF_IGNR, 36 CLS_ACPT, 37 CLS_IGNR 38 }; 39 40 static const char * const mplstates[] = { 41 [NL80211_PLINK_LISTEN] = "LISTEN", 42 [NL80211_PLINK_OPN_SNT] = "OPN-SNT", 43 [NL80211_PLINK_OPN_RCVD] = "OPN-RCVD", 44 [NL80211_PLINK_CNF_RCVD] = "CNF_RCVD", 45 [NL80211_PLINK_ESTAB] = "ESTAB", 46 [NL80211_PLINK_HOLDING] = "HOLDING", 47 [NL80211_PLINK_BLOCKED] = "BLOCKED" 48 }; 49 50 static const char * const mplevents[] = { 51 [PLINK_UNDEFINED] = "NONE", 52 [OPN_ACPT] = "OPN_ACPT", 53 [OPN_RJCT] = "OPN_RJCT", 54 [OPN_IGNR] = "OPN_IGNR", 55 [CNF_ACPT] = "CNF_ACPT", 56 [CNF_RJCT] = "CNF_RJCT", 57 [CNF_IGNR] = "CNF_IGNR", 58 [CLS_ACPT] = "CLS_ACPT", 59 [CLS_IGNR] = "CLS_IGNR" 60 }; 61 62 static int mesh_plink_frame_tx(struct ieee80211_sub_if_data *sdata, 63 enum ieee80211_self_protected_actioncode action, 64 u8 *da, __le16 llid, __le16 plid, __le16 reason); 65 66 /** 67 * mesh_plink_fsm_restart - restart a mesh peer link finite state machine 68 * 69 * @sta: mesh peer link to restart 70 * 71 * Locking: this function must be called holding sta->lock 72 */ 73 static inline void mesh_plink_fsm_restart(struct sta_info *sta) 74 { 75 sta->plink_state = NL80211_PLINK_LISTEN; 76 sta->llid = sta->plid = sta->reason = 0; 77 sta->plink_retries = 0; 78 } 79 80 /* 81 * mesh_set_short_slot_time - enable / disable ERP short slot time. 82 * 83 * The standard indirectly mandates mesh STAs to turn off short slot time by 84 * disallowing advertising this (802.11-2012 8.4.1.4), but that doesn't mean we 85 * can't be sneaky about it. Enable short slot time if all mesh STAs in the 86 * MBSS support ERP rates. 87 * 88 * Returns BSS_CHANGED_ERP_SLOT or 0 for no change. 89 */ 90 static u32 mesh_set_short_slot_time(struct ieee80211_sub_if_data *sdata) 91 { 92 struct ieee80211_local *local = sdata->local; 93 enum ieee80211_band band = ieee80211_get_sdata_band(sdata); 94 struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band]; 95 struct sta_info *sta; 96 u32 erp_rates = 0, changed = 0; 97 int i; 98 bool short_slot = false; 99 100 if (band == IEEE80211_BAND_5GHZ) { 101 /* (IEEE 802.11-2012 19.4.5) */ 102 short_slot = true; 103 goto out; 104 } else if (band != IEEE80211_BAND_2GHZ || 105 (band == IEEE80211_BAND_2GHZ && 106 local->hw.flags & IEEE80211_HW_2GHZ_SHORT_SLOT_INCAPABLE)) 107 goto out; 108 109 for (i = 0; i < sband->n_bitrates; i++) 110 if (sband->bitrates[i].flags & IEEE80211_RATE_ERP_G) 111 erp_rates |= BIT(i); 112 113 if (!erp_rates) 114 goto out; 115 116 rcu_read_lock(); 117 list_for_each_entry_rcu(sta, &local->sta_list, list) { 118 if (sdata != sta->sdata || 119 sta->plink_state != NL80211_PLINK_ESTAB) 120 continue; 121 122 short_slot = false; 123 if (erp_rates & sta->sta.supp_rates[band]) 124 short_slot = true; 125 else 126 break; 127 } 128 rcu_read_unlock(); 129 130 out: 131 if (sdata->vif.bss_conf.use_short_slot != short_slot) { 132 sdata->vif.bss_conf.use_short_slot = short_slot; 133 changed = BSS_CHANGED_ERP_SLOT; 134 mpl_dbg(sdata, "mesh_plink %pM: ERP short slot time %d\n", 135 sdata->vif.addr, short_slot); 136 } 137 return changed; 138 } 139 140 /** 141 * mesh_set_ht_prot_mode - set correct HT protection mode 142 * 143 * Section 9.23.3.5 of IEEE 80211-2012 describes the protection rules for HT 144 * mesh STA in a MBSS. Three HT protection modes are supported for now, non-HT 145 * mixed mode, 20MHz-protection and no-protection mode. non-HT mixed mode is 146 * selected if any non-HT peers are present in our MBSS. 20MHz-protection mode 147 * is selected if all peers in our 20/40MHz MBSS support HT and atleast one 148 * HT20 peer is present. Otherwise no-protection mode is selected. 149 */ 150 static u32 mesh_set_ht_prot_mode(struct ieee80211_sub_if_data *sdata) 151 { 152 struct ieee80211_local *local = sdata->local; 153 struct sta_info *sta; 154 u16 ht_opmode; 155 bool non_ht_sta = false, ht20_sta = false; 156 157 if (sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT) 158 return 0; 159 160 rcu_read_lock(); 161 list_for_each_entry_rcu(sta, &local->sta_list, list) { 162 if (sdata != sta->sdata || 163 sta->plink_state != NL80211_PLINK_ESTAB) 164 continue; 165 166 if (sta->sta.bandwidth > IEEE80211_STA_RX_BW_20) 167 continue; 168 169 if (!sta->sta.ht_cap.ht_supported) { 170 mpl_dbg(sdata, "nonHT sta (%pM) is present\n", 171 sta->sta.addr); 172 non_ht_sta = true; 173 break; 174 } 175 176 mpl_dbg(sdata, "HT20 sta (%pM) is present\n", sta->sta.addr); 177 ht20_sta = true; 178 } 179 rcu_read_unlock(); 180 181 if (non_ht_sta) 182 ht_opmode = IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED; 183 else if (ht20_sta && 184 sdata->vif.bss_conf.chandef.width > NL80211_CHAN_WIDTH_20) 185 ht_opmode = IEEE80211_HT_OP_MODE_PROTECTION_20MHZ; 186 else 187 ht_opmode = IEEE80211_HT_OP_MODE_PROTECTION_NONE; 188 189 if (sdata->vif.bss_conf.ht_operation_mode == ht_opmode) 190 return 0; 191 192 sdata->vif.bss_conf.ht_operation_mode = ht_opmode; 193 sdata->u.mesh.mshcfg.ht_opmode = ht_opmode; 194 mpl_dbg(sdata, "selected new HT protection mode %d\n", ht_opmode); 195 return BSS_CHANGED_HT; 196 } 197 198 /** 199 * __mesh_plink_deactivate - deactivate mesh peer link 200 * 201 * @sta: mesh peer link to deactivate 202 * 203 * All mesh paths with this peer as next hop will be flushed 204 * Returns beacon changed flag if the beacon content changed. 205 * 206 * Locking: the caller must hold sta->lock 207 */ 208 static u32 __mesh_plink_deactivate(struct sta_info *sta) 209 { 210 struct ieee80211_sub_if_data *sdata = sta->sdata; 211 u32 changed = 0; 212 213 if (sta->plink_state == NL80211_PLINK_ESTAB) 214 changed = mesh_plink_dec_estab_count(sdata); 215 sta->plink_state = NL80211_PLINK_BLOCKED; 216 mesh_path_flush_by_nexthop(sta); 217 218 ieee80211_mps_sta_status_update(sta); 219 changed |= ieee80211_mps_local_status_update(sdata); 220 221 return changed; 222 } 223 224 /** 225 * mesh_plink_deactivate - deactivate mesh peer link 226 * 227 * @sta: mesh peer link to deactivate 228 * 229 * All mesh paths with this peer as next hop will be flushed 230 */ 231 u32 mesh_plink_deactivate(struct sta_info *sta) 232 { 233 struct ieee80211_sub_if_data *sdata = sta->sdata; 234 u32 changed; 235 236 spin_lock_bh(&sta->lock); 237 changed = __mesh_plink_deactivate(sta); 238 sta->reason = cpu_to_le16(WLAN_REASON_MESH_PEER_CANCELED); 239 mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_CLOSE, 240 sta->sta.addr, sta->llid, sta->plid, 241 sta->reason); 242 spin_unlock_bh(&sta->lock); 243 244 return changed; 245 } 246 247 static int mesh_plink_frame_tx(struct ieee80211_sub_if_data *sdata, 248 enum ieee80211_self_protected_actioncode action, 249 u8 *da, __le16 llid, __le16 plid, __le16 reason) 250 { 251 struct ieee80211_local *local = sdata->local; 252 struct sk_buff *skb; 253 struct ieee80211_tx_info *info; 254 struct ieee80211_mgmt *mgmt; 255 bool include_plid = false; 256 u16 peering_proto = 0; 257 u8 *pos, ie_len = 4; 258 int hdr_len = offsetof(struct ieee80211_mgmt, u.action.u.self_prot) + 259 sizeof(mgmt->u.action.u.self_prot); 260 int err = -ENOMEM; 261 262 skb = dev_alloc_skb(local->tx_headroom + 263 hdr_len + 264 2 + /* capability info */ 265 2 + /* AID */ 266 2 + 8 + /* supported rates */ 267 2 + (IEEE80211_MAX_SUPP_RATES - 8) + 268 2 + sdata->u.mesh.mesh_id_len + 269 2 + sizeof(struct ieee80211_meshconf_ie) + 270 2 + sizeof(struct ieee80211_ht_cap) + 271 2 + sizeof(struct ieee80211_ht_operation) + 272 2 + 8 + /* peering IE */ 273 sdata->u.mesh.ie_len); 274 if (!skb) 275 return -1; 276 info = IEEE80211_SKB_CB(skb); 277 skb_reserve(skb, local->tx_headroom); 278 mgmt = (struct ieee80211_mgmt *) skb_put(skb, hdr_len); 279 memset(mgmt, 0, hdr_len); 280 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 281 IEEE80211_STYPE_ACTION); 282 memcpy(mgmt->da, da, ETH_ALEN); 283 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN); 284 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN); 285 mgmt->u.action.category = WLAN_CATEGORY_SELF_PROTECTED; 286 mgmt->u.action.u.self_prot.action_code = action; 287 288 if (action != WLAN_SP_MESH_PEERING_CLOSE) { 289 enum ieee80211_band band = ieee80211_get_sdata_band(sdata); 290 291 /* capability info */ 292 pos = skb_put(skb, 2); 293 memset(pos, 0, 2); 294 if (action == WLAN_SP_MESH_PEERING_CONFIRM) { 295 /* AID */ 296 pos = skb_put(skb, 2); 297 memcpy(pos + 2, &plid, 2); 298 } 299 if (ieee80211_add_srates_ie(sdata, skb, true, band) || 300 ieee80211_add_ext_srates_ie(sdata, skb, true, band) || 301 mesh_add_rsn_ie(sdata, skb) || 302 mesh_add_meshid_ie(sdata, skb) || 303 mesh_add_meshconf_ie(sdata, skb)) 304 goto free; 305 } else { /* WLAN_SP_MESH_PEERING_CLOSE */ 306 info->flags |= IEEE80211_TX_CTL_NO_ACK; 307 if (mesh_add_meshid_ie(sdata, skb)) 308 goto free; 309 } 310 311 /* Add Mesh Peering Management element */ 312 switch (action) { 313 case WLAN_SP_MESH_PEERING_OPEN: 314 break; 315 case WLAN_SP_MESH_PEERING_CONFIRM: 316 ie_len += 2; 317 include_plid = true; 318 break; 319 case WLAN_SP_MESH_PEERING_CLOSE: 320 if (plid) { 321 ie_len += 2; 322 include_plid = true; 323 } 324 ie_len += 2; /* reason code */ 325 break; 326 default: 327 err = -EINVAL; 328 goto free; 329 } 330 331 if (WARN_ON(skb_tailroom(skb) < 2 + ie_len)) 332 goto free; 333 334 pos = skb_put(skb, 2 + ie_len); 335 *pos++ = WLAN_EID_PEER_MGMT; 336 *pos++ = ie_len; 337 memcpy(pos, &peering_proto, 2); 338 pos += 2; 339 memcpy(pos, &llid, 2); 340 pos += 2; 341 if (include_plid) { 342 memcpy(pos, &plid, 2); 343 pos += 2; 344 } 345 if (action == WLAN_SP_MESH_PEERING_CLOSE) { 346 memcpy(pos, &reason, 2); 347 pos += 2; 348 } 349 350 if (action != WLAN_SP_MESH_PEERING_CLOSE) { 351 if (mesh_add_ht_cap_ie(sdata, skb) || 352 mesh_add_ht_oper_ie(sdata, skb)) 353 goto free; 354 } 355 356 if (mesh_add_vendor_ies(sdata, skb)) 357 goto free; 358 359 ieee80211_tx_skb(sdata, skb); 360 return 0; 361 free: 362 kfree_skb(skb); 363 return err; 364 } 365 366 static void mesh_sta_info_init(struct ieee80211_sub_if_data *sdata, 367 struct sta_info *sta, 368 struct ieee802_11_elems *elems, bool insert) 369 { 370 struct ieee80211_local *local = sdata->local; 371 enum ieee80211_band band = ieee80211_get_sdata_band(sdata); 372 struct ieee80211_supported_band *sband; 373 u32 rates, basic_rates = 0, changed = 0; 374 375 sband = local->hw.wiphy->bands[band]; 376 rates = ieee80211_sta_get_rates(local, elems, band, &basic_rates); 377 378 spin_lock_bh(&sta->lock); 379 sta->last_rx = jiffies; 380 381 /* rates and capabilities don't change during peering */ 382 if (sta->plink_state == NL80211_PLINK_ESTAB) 383 goto out; 384 385 if (sta->sta.supp_rates[band] != rates) 386 changed |= IEEE80211_RC_SUPP_RATES_CHANGED; 387 sta->sta.supp_rates[band] = rates; 388 389 if (ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband, 390 elems->ht_cap_elem, sta)) 391 changed |= IEEE80211_RC_BW_CHANGED; 392 393 /* HT peer is operating 20MHz-only */ 394 if (elems->ht_operation && 395 !(elems->ht_operation->ht_param & 396 IEEE80211_HT_PARAM_CHAN_WIDTH_ANY)) { 397 if (sta->sta.bandwidth != IEEE80211_STA_RX_BW_20) 398 changed |= IEEE80211_RC_BW_CHANGED; 399 sta->sta.bandwidth = IEEE80211_STA_RX_BW_20; 400 } 401 402 if (insert) 403 rate_control_rate_init(sta); 404 else 405 rate_control_rate_update(local, sband, sta, changed); 406 out: 407 spin_unlock_bh(&sta->lock); 408 } 409 410 static struct sta_info * 411 __mesh_sta_info_alloc(struct ieee80211_sub_if_data *sdata, u8 *hw_addr) 412 { 413 struct sta_info *sta; 414 415 if (sdata->local->num_sta >= MESH_MAX_PLINKS) 416 return NULL; 417 418 sta = sta_info_alloc(sdata, hw_addr, GFP_KERNEL); 419 if (!sta) 420 return NULL; 421 422 sta->plink_state = NL80211_PLINK_LISTEN; 423 init_timer(&sta->plink_timer); 424 425 sta_info_pre_move_state(sta, IEEE80211_STA_AUTH); 426 sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC); 427 sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED); 428 429 set_sta_flag(sta, WLAN_STA_WME); 430 431 return sta; 432 } 433 434 static struct sta_info * 435 mesh_sta_info_alloc(struct ieee80211_sub_if_data *sdata, u8 *addr, 436 struct ieee802_11_elems *elems) 437 { 438 struct sta_info *sta = NULL; 439 440 /* Userspace handles peer allocation when security is enabled */ 441 if (sdata->u.mesh.security & IEEE80211_MESH_SEC_AUTHED) 442 cfg80211_notify_new_peer_candidate(sdata->dev, addr, 443 elems->ie_start, 444 elems->total_len, 445 GFP_KERNEL); 446 else 447 sta = __mesh_sta_info_alloc(sdata, addr); 448 449 return sta; 450 } 451 452 /* 453 * mesh_sta_info_get - return mesh sta info entry for @addr. 454 * 455 * @sdata: local meshif 456 * @addr: peer's address 457 * @elems: IEs from beacon or mesh peering frame. 458 * 459 * Return existing or newly allocated sta_info under RCU read lock. 460 * (re)initialize with given IEs. 461 */ 462 static struct sta_info * 463 mesh_sta_info_get(struct ieee80211_sub_if_data *sdata, 464 u8 *addr, struct ieee802_11_elems *elems) __acquires(RCU) 465 { 466 struct sta_info *sta = NULL; 467 468 rcu_read_lock(); 469 sta = sta_info_get(sdata, addr); 470 if (sta) { 471 mesh_sta_info_init(sdata, sta, elems, false); 472 } else { 473 rcu_read_unlock(); 474 /* can't run atomic */ 475 sta = mesh_sta_info_alloc(sdata, addr, elems); 476 if (!sta) { 477 rcu_read_lock(); 478 return NULL; 479 } 480 481 mesh_sta_info_init(sdata, sta, elems, true); 482 483 if (sta_info_insert_rcu(sta)) 484 return NULL; 485 } 486 487 return sta; 488 } 489 490 /* 491 * mesh_neighbour_update - update or initialize new mesh neighbor. 492 * 493 * @sdata: local meshif 494 * @addr: peer's address 495 * @elems: IEs from beacon or mesh peering frame 496 * 497 * Initiates peering if appropriate. 498 */ 499 void mesh_neighbour_update(struct ieee80211_sub_if_data *sdata, 500 u8 *hw_addr, 501 struct ieee802_11_elems *elems) 502 { 503 struct sta_info *sta; 504 u32 changed = 0; 505 506 sta = mesh_sta_info_get(sdata, hw_addr, elems); 507 if (!sta) 508 goto out; 509 510 if (mesh_peer_accepts_plinks(elems) && 511 sta->plink_state == NL80211_PLINK_LISTEN && 512 sdata->u.mesh.accepting_plinks && 513 sdata->u.mesh.mshcfg.auto_open_plinks && 514 rssi_threshold_check(sta, sdata)) 515 changed = mesh_plink_open(sta); 516 517 ieee80211_mps_frame_release(sta, elems); 518 out: 519 rcu_read_unlock(); 520 ieee80211_mbss_info_change_notify(sdata, changed); 521 } 522 523 static void mesh_plink_timer(unsigned long data) 524 { 525 struct sta_info *sta; 526 __le16 llid, plid, reason; 527 struct ieee80211_sub_if_data *sdata; 528 struct mesh_config *mshcfg; 529 530 /* 531 * This STA is valid because sta_info_destroy() will 532 * del_timer_sync() this timer after having made sure 533 * it cannot be readded (by deleting the plink.) 534 */ 535 sta = (struct sta_info *) data; 536 537 if (sta->sdata->local->quiescing) { 538 sta->plink_timer_was_running = true; 539 return; 540 } 541 542 spin_lock_bh(&sta->lock); 543 if (sta->ignore_plink_timer) { 544 sta->ignore_plink_timer = false; 545 spin_unlock_bh(&sta->lock); 546 return; 547 } 548 mpl_dbg(sta->sdata, 549 "Mesh plink timer for %pM fired on state %d\n", 550 sta->sta.addr, sta->plink_state); 551 reason = 0; 552 llid = sta->llid; 553 plid = sta->plid; 554 sdata = sta->sdata; 555 mshcfg = &sdata->u.mesh.mshcfg; 556 557 switch (sta->plink_state) { 558 case NL80211_PLINK_OPN_RCVD: 559 case NL80211_PLINK_OPN_SNT: 560 /* retry timer */ 561 if (sta->plink_retries < mshcfg->dot11MeshMaxRetries) { 562 u32 rand; 563 mpl_dbg(sta->sdata, 564 "Mesh plink for %pM (retry, timeout): %d %d\n", 565 sta->sta.addr, sta->plink_retries, 566 sta->plink_timeout); 567 get_random_bytes(&rand, sizeof(u32)); 568 sta->plink_timeout = sta->plink_timeout + 569 rand % sta->plink_timeout; 570 ++sta->plink_retries; 571 mod_plink_timer(sta, sta->plink_timeout); 572 spin_unlock_bh(&sta->lock); 573 mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_OPEN, 574 sta->sta.addr, llid, 0, 0); 575 break; 576 } 577 reason = cpu_to_le16(WLAN_REASON_MESH_MAX_RETRIES); 578 /* fall through on else */ 579 case NL80211_PLINK_CNF_RCVD: 580 /* confirm timer */ 581 if (!reason) 582 reason = cpu_to_le16(WLAN_REASON_MESH_CONFIRM_TIMEOUT); 583 sta->plink_state = NL80211_PLINK_HOLDING; 584 mod_plink_timer(sta, mshcfg->dot11MeshHoldingTimeout); 585 spin_unlock_bh(&sta->lock); 586 mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_CLOSE, 587 sta->sta.addr, llid, plid, reason); 588 break; 589 case NL80211_PLINK_HOLDING: 590 /* holding timer */ 591 del_timer(&sta->plink_timer); 592 mesh_plink_fsm_restart(sta); 593 spin_unlock_bh(&sta->lock); 594 break; 595 default: 596 spin_unlock_bh(&sta->lock); 597 break; 598 } 599 } 600 601 #ifdef CONFIG_PM 602 void mesh_plink_quiesce(struct sta_info *sta) 603 { 604 if (!ieee80211_vif_is_mesh(&sta->sdata->vif)) 605 return; 606 607 /* no kernel mesh sta timers have been initialized */ 608 if (sta->sdata->u.mesh.security != IEEE80211_MESH_SEC_NONE) 609 return; 610 611 if (del_timer_sync(&sta->plink_timer)) 612 sta->plink_timer_was_running = true; 613 } 614 615 void mesh_plink_restart(struct sta_info *sta) 616 { 617 if (sta->plink_timer_was_running) { 618 add_timer(&sta->plink_timer); 619 sta->plink_timer_was_running = false; 620 } 621 } 622 #endif 623 624 static inline void mesh_plink_timer_set(struct sta_info *sta, int timeout) 625 { 626 sta->plink_timer.expires = jiffies + (HZ * timeout / 1000); 627 sta->plink_timer.data = (unsigned long) sta; 628 sta->plink_timer.function = mesh_plink_timer; 629 sta->plink_timeout = timeout; 630 add_timer(&sta->plink_timer); 631 } 632 633 u32 mesh_plink_open(struct sta_info *sta) 634 { 635 __le16 llid; 636 struct ieee80211_sub_if_data *sdata = sta->sdata; 637 u32 changed; 638 639 if (!test_sta_flag(sta, WLAN_STA_AUTH)) 640 return 0; 641 642 spin_lock_bh(&sta->lock); 643 get_random_bytes(&llid, 2); 644 sta->llid = llid; 645 if (sta->plink_state != NL80211_PLINK_LISTEN && 646 sta->plink_state != NL80211_PLINK_BLOCKED) { 647 spin_unlock_bh(&sta->lock); 648 return 0; 649 } 650 sta->plink_state = NL80211_PLINK_OPN_SNT; 651 mesh_plink_timer_set(sta, sdata->u.mesh.mshcfg.dot11MeshRetryTimeout); 652 spin_unlock_bh(&sta->lock); 653 mpl_dbg(sdata, 654 "Mesh plink: starting establishment with %pM\n", 655 sta->sta.addr); 656 657 /* set the non-peer mode to active during peering */ 658 changed = ieee80211_mps_local_status_update(sdata); 659 660 mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_OPEN, 661 sta->sta.addr, llid, 0, 0); 662 return changed; 663 } 664 665 u32 mesh_plink_block(struct sta_info *sta) 666 { 667 u32 changed; 668 669 spin_lock_bh(&sta->lock); 670 changed = __mesh_plink_deactivate(sta); 671 sta->plink_state = NL80211_PLINK_BLOCKED; 672 spin_unlock_bh(&sta->lock); 673 674 return changed; 675 } 676 677 678 void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata, 679 struct ieee80211_mgmt *mgmt, size_t len, 680 struct ieee80211_rx_status *rx_status) 681 { 682 struct mesh_config *mshcfg = &sdata->u.mesh.mshcfg; 683 struct ieee802_11_elems elems; 684 struct sta_info *sta; 685 enum plink_event event; 686 enum ieee80211_self_protected_actioncode ftype; 687 size_t baselen; 688 bool matches_local = true; 689 u8 ie_len; 690 u8 *baseaddr; 691 u32 changed = 0; 692 __le16 plid, llid, reason; 693 694 /* need action_code, aux */ 695 if (len < IEEE80211_MIN_ACTION_SIZE + 3) 696 return; 697 698 if (is_multicast_ether_addr(mgmt->da)) { 699 mpl_dbg(sdata, 700 "Mesh plink: ignore frame from multicast address\n"); 701 return; 702 } 703 704 baseaddr = mgmt->u.action.u.self_prot.variable; 705 baselen = (u8 *) mgmt->u.action.u.self_prot.variable - (u8 *) mgmt; 706 if (mgmt->u.action.u.self_prot.action_code == 707 WLAN_SP_MESH_PEERING_CONFIRM) { 708 baseaddr += 4; 709 baselen += 4; 710 } 711 ieee802_11_parse_elems(baseaddr, len - baselen, &elems); 712 713 if (!elems.peering) { 714 mpl_dbg(sdata, 715 "Mesh plink: missing necessary peer link ie\n"); 716 return; 717 } 718 719 if (elems.rsn_len && 720 sdata->u.mesh.security == IEEE80211_MESH_SEC_NONE) { 721 mpl_dbg(sdata, 722 "Mesh plink: can't establish link with secure peer\n"); 723 return; 724 } 725 726 ftype = mgmt->u.action.u.self_prot.action_code; 727 ie_len = elems.peering_len; 728 if ((ftype == WLAN_SP_MESH_PEERING_OPEN && ie_len != 4) || 729 (ftype == WLAN_SP_MESH_PEERING_CONFIRM && ie_len != 6) || 730 (ftype == WLAN_SP_MESH_PEERING_CLOSE && ie_len != 6 731 && ie_len != 8)) { 732 mpl_dbg(sdata, 733 "Mesh plink: incorrect plink ie length %d %d\n", 734 ftype, ie_len); 735 return; 736 } 737 738 if (ftype != WLAN_SP_MESH_PEERING_CLOSE && 739 (!elems.mesh_id || !elems.mesh_config)) { 740 mpl_dbg(sdata, "Mesh plink: missing necessary ie\n"); 741 return; 742 } 743 /* Note the lines below are correct, the llid in the frame is the plid 744 * from the point of view of this host. 745 */ 746 memcpy(&plid, PLINK_GET_LLID(elems.peering), 2); 747 if (ftype == WLAN_SP_MESH_PEERING_CONFIRM || 748 (ftype == WLAN_SP_MESH_PEERING_CLOSE && ie_len == 8)) 749 memcpy(&llid, PLINK_GET_PLID(elems.peering), 2); 750 751 /* WARNING: Only for sta pointer, is dropped & re-acquired */ 752 rcu_read_lock(); 753 754 sta = sta_info_get(sdata, mgmt->sa); 755 if (!sta && ftype != WLAN_SP_MESH_PEERING_OPEN) { 756 mpl_dbg(sdata, "Mesh plink: cls or cnf from unknown peer\n"); 757 rcu_read_unlock(); 758 return; 759 } 760 761 if (ftype == WLAN_SP_MESH_PEERING_OPEN && 762 !rssi_threshold_check(sta, sdata)) { 763 mpl_dbg(sdata, "Mesh plink: %pM does not meet rssi threshold\n", 764 mgmt->sa); 765 rcu_read_unlock(); 766 return; 767 } 768 769 if (sta && !test_sta_flag(sta, WLAN_STA_AUTH)) { 770 mpl_dbg(sdata, "Mesh plink: Action frame from non-authed peer\n"); 771 rcu_read_unlock(); 772 return; 773 } 774 775 if (sta && sta->plink_state == NL80211_PLINK_BLOCKED) { 776 rcu_read_unlock(); 777 return; 778 } 779 780 /* Now we will figure out the appropriate event... */ 781 event = PLINK_UNDEFINED; 782 if (ftype != WLAN_SP_MESH_PEERING_CLOSE && 783 !mesh_matches_local(sdata, &elems)) { 784 matches_local = false; 785 switch (ftype) { 786 case WLAN_SP_MESH_PEERING_OPEN: 787 event = OPN_RJCT; 788 break; 789 case WLAN_SP_MESH_PEERING_CONFIRM: 790 event = CNF_RJCT; 791 break; 792 default: 793 break; 794 } 795 } 796 797 if (!sta && !matches_local) { 798 rcu_read_unlock(); 799 reason = cpu_to_le16(WLAN_REASON_MESH_CONFIG); 800 llid = 0; 801 mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_CLOSE, 802 mgmt->sa, llid, plid, reason); 803 return; 804 } else if (!sta) { 805 /* ftype == WLAN_SP_MESH_PEERING_OPEN */ 806 if (!mesh_plink_free_count(sdata)) { 807 mpl_dbg(sdata, "Mesh plink error: no more free plinks\n"); 808 rcu_read_unlock(); 809 return; 810 } 811 event = OPN_ACPT; 812 } else if (matches_local) { 813 switch (ftype) { 814 case WLAN_SP_MESH_PEERING_OPEN: 815 if (!mesh_plink_free_count(sdata) || 816 (sta->plid && sta->plid != plid)) 817 event = OPN_IGNR; 818 else 819 event = OPN_ACPT; 820 break; 821 case WLAN_SP_MESH_PEERING_CONFIRM: 822 if (!mesh_plink_free_count(sdata) || 823 (sta->llid != llid || sta->plid != plid)) 824 event = CNF_IGNR; 825 else 826 event = CNF_ACPT; 827 break; 828 case WLAN_SP_MESH_PEERING_CLOSE: 829 if (sta->plink_state == NL80211_PLINK_ESTAB) 830 /* Do not check for llid or plid. This does not 831 * follow the standard but since multiple plinks 832 * per sta are not supported, it is necessary in 833 * order to avoid a livelock when MP A sees an 834 * establish peer link to MP B but MP B does not 835 * see it. This can be caused by a timeout in 836 * B's peer link establishment or B beign 837 * restarted. 838 */ 839 event = CLS_ACPT; 840 else if (sta->plid != plid) 841 event = CLS_IGNR; 842 else if (ie_len == 7 && sta->llid != llid) 843 event = CLS_IGNR; 844 else 845 event = CLS_ACPT; 846 break; 847 default: 848 mpl_dbg(sdata, "Mesh plink: unknown frame subtype\n"); 849 rcu_read_unlock(); 850 return; 851 } 852 } 853 854 if (event == OPN_ACPT) { 855 rcu_read_unlock(); 856 /* allocate sta entry if necessary and update info */ 857 sta = mesh_sta_info_get(sdata, mgmt->sa, &elems); 858 if (!sta) { 859 mpl_dbg(sdata, "Mesh plink: failed to init peer!\n"); 860 rcu_read_unlock(); 861 return; 862 } 863 } 864 865 mpl_dbg(sdata, "peer %pM in state %s got event %s\n", mgmt->sa, 866 mplstates[sta->plink_state], mplevents[event]); 867 reason = 0; 868 spin_lock_bh(&sta->lock); 869 switch (sta->plink_state) { 870 /* spin_unlock as soon as state is updated at each case */ 871 case NL80211_PLINK_LISTEN: 872 switch (event) { 873 case CLS_ACPT: 874 mesh_plink_fsm_restart(sta); 875 spin_unlock_bh(&sta->lock); 876 break; 877 case OPN_ACPT: 878 sta->plink_state = NL80211_PLINK_OPN_RCVD; 879 sta->plid = plid; 880 get_random_bytes(&llid, 2); 881 sta->llid = llid; 882 mesh_plink_timer_set(sta, 883 mshcfg->dot11MeshRetryTimeout); 884 885 /* set the non-peer mode to active during peering */ 886 changed |= ieee80211_mps_local_status_update(sdata); 887 888 spin_unlock_bh(&sta->lock); 889 mesh_plink_frame_tx(sdata, 890 WLAN_SP_MESH_PEERING_OPEN, 891 sta->sta.addr, llid, 0, 0); 892 mesh_plink_frame_tx(sdata, 893 WLAN_SP_MESH_PEERING_CONFIRM, 894 sta->sta.addr, llid, plid, 0); 895 break; 896 default: 897 spin_unlock_bh(&sta->lock); 898 break; 899 } 900 break; 901 902 case NL80211_PLINK_OPN_SNT: 903 switch (event) { 904 case OPN_RJCT: 905 case CNF_RJCT: 906 reason = cpu_to_le16(WLAN_REASON_MESH_CONFIG); 907 case CLS_ACPT: 908 if (!reason) 909 reason = cpu_to_le16(WLAN_REASON_MESH_CLOSE); 910 sta->reason = reason; 911 sta->plink_state = NL80211_PLINK_HOLDING; 912 if (!mod_plink_timer(sta, 913 mshcfg->dot11MeshHoldingTimeout)) 914 sta->ignore_plink_timer = true; 915 916 llid = sta->llid; 917 spin_unlock_bh(&sta->lock); 918 mesh_plink_frame_tx(sdata, 919 WLAN_SP_MESH_PEERING_CLOSE, 920 sta->sta.addr, llid, plid, reason); 921 break; 922 case OPN_ACPT: 923 /* retry timer is left untouched */ 924 sta->plink_state = NL80211_PLINK_OPN_RCVD; 925 sta->plid = plid; 926 llid = sta->llid; 927 spin_unlock_bh(&sta->lock); 928 mesh_plink_frame_tx(sdata, 929 WLAN_SP_MESH_PEERING_CONFIRM, 930 sta->sta.addr, llid, plid, 0); 931 break; 932 case CNF_ACPT: 933 sta->plink_state = NL80211_PLINK_CNF_RCVD; 934 if (!mod_plink_timer(sta, 935 mshcfg->dot11MeshConfirmTimeout)) 936 sta->ignore_plink_timer = true; 937 938 spin_unlock_bh(&sta->lock); 939 break; 940 default: 941 spin_unlock_bh(&sta->lock); 942 break; 943 } 944 break; 945 946 case NL80211_PLINK_OPN_RCVD: 947 switch (event) { 948 case OPN_RJCT: 949 case CNF_RJCT: 950 reason = cpu_to_le16(WLAN_REASON_MESH_CONFIG); 951 case CLS_ACPT: 952 if (!reason) 953 reason = cpu_to_le16(WLAN_REASON_MESH_CLOSE); 954 sta->reason = reason; 955 sta->plink_state = NL80211_PLINK_HOLDING; 956 if (!mod_plink_timer(sta, 957 mshcfg->dot11MeshHoldingTimeout)) 958 sta->ignore_plink_timer = true; 959 960 llid = sta->llid; 961 spin_unlock_bh(&sta->lock); 962 mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_CLOSE, 963 sta->sta.addr, llid, plid, reason); 964 break; 965 case OPN_ACPT: 966 llid = sta->llid; 967 spin_unlock_bh(&sta->lock); 968 mesh_plink_frame_tx(sdata, 969 WLAN_SP_MESH_PEERING_CONFIRM, 970 sta->sta.addr, llid, plid, 0); 971 break; 972 case CNF_ACPT: 973 del_timer(&sta->plink_timer); 974 sta->plink_state = NL80211_PLINK_ESTAB; 975 spin_unlock_bh(&sta->lock); 976 changed |= mesh_plink_inc_estab_count(sdata); 977 changed |= mesh_set_ht_prot_mode(sdata); 978 changed |= mesh_set_short_slot_time(sdata); 979 mpl_dbg(sdata, "Mesh plink with %pM ESTABLISHED\n", 980 sta->sta.addr); 981 ieee80211_mps_sta_status_update(sta); 982 changed |= ieee80211_mps_set_sta_local_pm(sta, 983 mshcfg->power_mode); 984 break; 985 default: 986 spin_unlock_bh(&sta->lock); 987 break; 988 } 989 break; 990 991 case NL80211_PLINK_CNF_RCVD: 992 switch (event) { 993 case OPN_RJCT: 994 case CNF_RJCT: 995 reason = cpu_to_le16(WLAN_REASON_MESH_CONFIG); 996 case CLS_ACPT: 997 if (!reason) 998 reason = cpu_to_le16(WLAN_REASON_MESH_CLOSE); 999 sta->reason = reason; 1000 sta->plink_state = NL80211_PLINK_HOLDING; 1001 if (!mod_plink_timer(sta, 1002 mshcfg->dot11MeshHoldingTimeout)) 1003 sta->ignore_plink_timer = true; 1004 1005 llid = sta->llid; 1006 spin_unlock_bh(&sta->lock); 1007 mesh_plink_frame_tx(sdata, 1008 WLAN_SP_MESH_PEERING_CLOSE, 1009 sta->sta.addr, llid, plid, reason); 1010 break; 1011 case OPN_ACPT: 1012 del_timer(&sta->plink_timer); 1013 sta->plink_state = NL80211_PLINK_ESTAB; 1014 spin_unlock_bh(&sta->lock); 1015 changed |= mesh_plink_inc_estab_count(sdata); 1016 changed |= mesh_set_ht_prot_mode(sdata); 1017 changed |= mesh_set_short_slot_time(sdata); 1018 mpl_dbg(sdata, "Mesh plink with %pM ESTABLISHED\n", 1019 sta->sta.addr); 1020 mesh_plink_frame_tx(sdata, 1021 WLAN_SP_MESH_PEERING_CONFIRM, 1022 sta->sta.addr, llid, plid, 0); 1023 ieee80211_mps_sta_status_update(sta); 1024 changed |= ieee80211_mps_set_sta_local_pm(sta, 1025 mshcfg->power_mode); 1026 break; 1027 default: 1028 spin_unlock_bh(&sta->lock); 1029 break; 1030 } 1031 break; 1032 1033 case NL80211_PLINK_ESTAB: 1034 switch (event) { 1035 case CLS_ACPT: 1036 reason = cpu_to_le16(WLAN_REASON_MESH_CLOSE); 1037 sta->reason = reason; 1038 changed |= __mesh_plink_deactivate(sta); 1039 sta->plink_state = NL80211_PLINK_HOLDING; 1040 llid = sta->llid; 1041 mod_plink_timer(sta, mshcfg->dot11MeshHoldingTimeout); 1042 spin_unlock_bh(&sta->lock); 1043 changed |= mesh_set_ht_prot_mode(sdata); 1044 changed |= mesh_set_short_slot_time(sdata); 1045 mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_CLOSE, 1046 sta->sta.addr, llid, plid, reason); 1047 break; 1048 case OPN_ACPT: 1049 llid = sta->llid; 1050 spin_unlock_bh(&sta->lock); 1051 mesh_plink_frame_tx(sdata, 1052 WLAN_SP_MESH_PEERING_CONFIRM, 1053 sta->sta.addr, llid, plid, 0); 1054 break; 1055 default: 1056 spin_unlock_bh(&sta->lock); 1057 break; 1058 } 1059 break; 1060 case NL80211_PLINK_HOLDING: 1061 switch (event) { 1062 case CLS_ACPT: 1063 if (del_timer(&sta->plink_timer)) 1064 sta->ignore_plink_timer = 1; 1065 mesh_plink_fsm_restart(sta); 1066 spin_unlock_bh(&sta->lock); 1067 break; 1068 case OPN_ACPT: 1069 case CNF_ACPT: 1070 case OPN_RJCT: 1071 case CNF_RJCT: 1072 llid = sta->llid; 1073 reason = sta->reason; 1074 spin_unlock_bh(&sta->lock); 1075 mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_CLOSE, 1076 sta->sta.addr, llid, plid, reason); 1077 break; 1078 default: 1079 spin_unlock_bh(&sta->lock); 1080 } 1081 break; 1082 default: 1083 /* should not get here, PLINK_BLOCKED is dealt with at the 1084 * beginning of the function 1085 */ 1086 spin_unlock_bh(&sta->lock); 1087 break; 1088 } 1089 1090 rcu_read_unlock(); 1091 1092 if (changed) 1093 ieee80211_mbss_info_change_notify(sdata, changed); 1094 } 1095