mesh_plink.c revision 52ac8c488774b7ac6d1b0ed4c323b5de90d39d6e
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 28enum 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 40static int mesh_plink_frame_tx(struct ieee80211_sub_if_data *sdata, 41 enum ieee80211_self_protected_actioncode action, 42 u8 *da, __le16 llid, __le16 plid, __le16 reason); 43 44/** 45 * mesh_plink_fsm_restart - restart a mesh peer link finite state machine 46 * 47 * @sta: mesh peer link to restart 48 * 49 * Locking: this function must be called holding sta->lock 50 */ 51static inline void mesh_plink_fsm_restart(struct sta_info *sta) 52{ 53 sta->plink_state = NL80211_PLINK_LISTEN; 54 sta->llid = sta->plid = sta->reason = 0; 55 sta->plink_retries = 0; 56} 57 58/* 59 * mesh_set_short_slot_time - enable / disable ERP short slot time. 60 * 61 * The standard indirectly mandates mesh STAs to turn off short slot time by 62 * disallowing advertising this (802.11-2012 8.4.1.4), but that doesn't mean we 63 * can't be sneaky about it. Enable short slot time if all mesh STAs in the 64 * MBSS support ERP rates. 65 * 66 * Returns BSS_CHANGED_ERP_SLOT or 0 for no change. 67 */ 68static u32 mesh_set_short_slot_time(struct ieee80211_sub_if_data *sdata) 69{ 70 struct ieee80211_local *local = sdata->local; 71 enum ieee80211_band band = ieee80211_get_sdata_band(sdata); 72 struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band]; 73 struct sta_info *sta; 74 u32 erp_rates = 0, changed = 0; 75 int i; 76 bool short_slot = false; 77 78 if (band == IEEE80211_BAND_5GHZ) { 79 /* (IEEE 802.11-2012 19.4.5) */ 80 short_slot = true; 81 goto out; 82 } else if (band != IEEE80211_BAND_2GHZ || 83 (band == IEEE80211_BAND_2GHZ && 84 local->hw.flags & IEEE80211_HW_2GHZ_SHORT_SLOT_INCAPABLE)) 85 goto out; 86 87 for (i = 0; i < sband->n_bitrates; i++) 88 if (sband->bitrates[i].flags & IEEE80211_RATE_ERP_G) 89 erp_rates |= BIT(i); 90 91 if (!erp_rates) 92 goto out; 93 94 rcu_read_lock(); 95 list_for_each_entry_rcu(sta, &local->sta_list, list) { 96 if (sdata != sta->sdata || 97 sta->plink_state != NL80211_PLINK_ESTAB) 98 continue; 99 100 short_slot = false; 101 if (erp_rates & sta->sta.supp_rates[band]) 102 short_slot = true; 103 else 104 break; 105 } 106 rcu_read_unlock(); 107 108out: 109 if (sdata->vif.bss_conf.use_short_slot != short_slot) { 110 sdata->vif.bss_conf.use_short_slot = short_slot; 111 changed = BSS_CHANGED_ERP_SLOT; 112 mpl_dbg(sdata, "mesh_plink %pM: ERP short slot time %d\n", 113 sdata->vif.addr, short_slot); 114 } 115 return changed; 116} 117 118/** 119 * mesh_set_ht_prot_mode - set correct HT protection mode 120 * 121 * Section 9.23.3.5 of IEEE 80211-2012 describes the protection rules for HT 122 * mesh STA in a MBSS. Three HT protection modes are supported for now, non-HT 123 * mixed mode, 20MHz-protection and no-protection mode. non-HT mixed mode is 124 * selected if any non-HT peers are present in our MBSS. 20MHz-protection mode 125 * is selected if all peers in our 20/40MHz MBSS support HT and atleast one 126 * HT20 peer is present. Otherwise no-protection mode is selected. 127 */ 128static u32 mesh_set_ht_prot_mode(struct ieee80211_sub_if_data *sdata) 129{ 130 struct ieee80211_local *local = sdata->local; 131 struct sta_info *sta; 132 u16 ht_opmode; 133 bool non_ht_sta = false, ht20_sta = false; 134 135 if (sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT) 136 return 0; 137 138 rcu_read_lock(); 139 list_for_each_entry_rcu(sta, &local->sta_list, list) { 140 if (sdata != sta->sdata || 141 sta->plink_state != NL80211_PLINK_ESTAB) 142 continue; 143 144 if (sta->sta.bandwidth > IEEE80211_STA_RX_BW_20) 145 continue; 146 147 if (!sta->sta.ht_cap.ht_supported) { 148 mpl_dbg(sdata, "nonHT sta (%pM) is present\n", 149 sta->sta.addr); 150 non_ht_sta = true; 151 break; 152 } 153 154 mpl_dbg(sdata, "HT20 sta (%pM) is present\n", sta->sta.addr); 155 ht20_sta = true; 156 } 157 rcu_read_unlock(); 158 159 if (non_ht_sta) 160 ht_opmode = IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED; 161 else if (ht20_sta && 162 sdata->vif.bss_conf.chandef.width > NL80211_CHAN_WIDTH_20) 163 ht_opmode = IEEE80211_HT_OP_MODE_PROTECTION_20MHZ; 164 else 165 ht_opmode = IEEE80211_HT_OP_MODE_PROTECTION_NONE; 166 167 if (sdata->vif.bss_conf.ht_operation_mode == ht_opmode) 168 return 0; 169 170 sdata->vif.bss_conf.ht_operation_mode = ht_opmode; 171 sdata->u.mesh.mshcfg.ht_opmode = ht_opmode; 172 mpl_dbg(sdata, "selected new HT protection mode %d\n", ht_opmode); 173 return BSS_CHANGED_HT; 174} 175 176/** 177 * __mesh_plink_deactivate - deactivate mesh peer link 178 * 179 * @sta: mesh peer link to deactivate 180 * 181 * All mesh paths with this peer as next hop will be flushed 182 * Returns beacon changed flag if the beacon content changed. 183 * 184 * Locking: the caller must hold sta->lock 185 */ 186static u32 __mesh_plink_deactivate(struct sta_info *sta) 187{ 188 struct ieee80211_sub_if_data *sdata = sta->sdata; 189 u32 changed = 0; 190 191 if (sta->plink_state == NL80211_PLINK_ESTAB) 192 changed = mesh_plink_dec_estab_count(sdata); 193 sta->plink_state = NL80211_PLINK_BLOCKED; 194 mesh_path_flush_by_nexthop(sta); 195 196 ieee80211_mps_sta_status_update(sta); 197 changed |= ieee80211_mps_local_status_update(sdata); 198 199 return changed; 200} 201 202/** 203 * mesh_plink_deactivate - deactivate mesh peer link 204 * 205 * @sta: mesh peer link to deactivate 206 * 207 * All mesh paths with this peer as next hop will be flushed 208 */ 209u32 mesh_plink_deactivate(struct sta_info *sta) 210{ 211 struct ieee80211_sub_if_data *sdata = sta->sdata; 212 u32 changed; 213 214 spin_lock_bh(&sta->lock); 215 changed = __mesh_plink_deactivate(sta); 216 sta->reason = cpu_to_le16(WLAN_REASON_MESH_PEER_CANCELED); 217 mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_CLOSE, 218 sta->sta.addr, sta->llid, sta->plid, 219 sta->reason); 220 spin_unlock_bh(&sta->lock); 221 222 return changed; 223} 224 225static int mesh_plink_frame_tx(struct ieee80211_sub_if_data *sdata, 226 enum ieee80211_self_protected_actioncode action, 227 u8 *da, __le16 llid, __le16 plid, __le16 reason) 228{ 229 struct ieee80211_local *local = sdata->local; 230 struct sk_buff *skb; 231 struct ieee80211_tx_info *info; 232 struct ieee80211_mgmt *mgmt; 233 bool include_plid = false; 234 u16 peering_proto = 0; 235 u8 *pos, ie_len = 4; 236 int hdr_len = offsetof(struct ieee80211_mgmt, u.action.u.self_prot) + 237 sizeof(mgmt->u.action.u.self_prot); 238 int err = -ENOMEM; 239 240 skb = dev_alloc_skb(local->tx_headroom + 241 hdr_len + 242 2 + /* capability info */ 243 2 + /* AID */ 244 2 + 8 + /* supported rates */ 245 2 + (IEEE80211_MAX_SUPP_RATES - 8) + 246 2 + sdata->u.mesh.mesh_id_len + 247 2 + sizeof(struct ieee80211_meshconf_ie) + 248 2 + sizeof(struct ieee80211_ht_cap) + 249 2 + sizeof(struct ieee80211_ht_operation) + 250 2 + 8 + /* peering IE */ 251 sdata->u.mesh.ie_len); 252 if (!skb) 253 return -1; 254 info = IEEE80211_SKB_CB(skb); 255 skb_reserve(skb, local->tx_headroom); 256 mgmt = (struct ieee80211_mgmt *) skb_put(skb, hdr_len); 257 memset(mgmt, 0, hdr_len); 258 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 259 IEEE80211_STYPE_ACTION); 260 memcpy(mgmt->da, da, ETH_ALEN); 261 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN); 262 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN); 263 mgmt->u.action.category = WLAN_CATEGORY_SELF_PROTECTED; 264 mgmt->u.action.u.self_prot.action_code = action; 265 266 if (action != WLAN_SP_MESH_PEERING_CLOSE) { 267 enum ieee80211_band band = ieee80211_get_sdata_band(sdata); 268 269 /* capability info */ 270 pos = skb_put(skb, 2); 271 memset(pos, 0, 2); 272 if (action == WLAN_SP_MESH_PEERING_CONFIRM) { 273 /* AID */ 274 pos = skb_put(skb, 2); 275 memcpy(pos + 2, &plid, 2); 276 } 277 if (ieee80211_add_srates_ie(sdata, skb, true, band) || 278 ieee80211_add_ext_srates_ie(sdata, skb, true, band) || 279 mesh_add_rsn_ie(sdata, skb) || 280 mesh_add_meshid_ie(sdata, skb) || 281 mesh_add_meshconf_ie(sdata, skb)) 282 goto free; 283 } else { /* WLAN_SP_MESH_PEERING_CLOSE */ 284 info->flags |= IEEE80211_TX_CTL_NO_ACK; 285 if (mesh_add_meshid_ie(sdata, skb)) 286 goto free; 287 } 288 289 /* Add Mesh Peering Management element */ 290 switch (action) { 291 case WLAN_SP_MESH_PEERING_OPEN: 292 break; 293 case WLAN_SP_MESH_PEERING_CONFIRM: 294 ie_len += 2; 295 include_plid = true; 296 break; 297 case WLAN_SP_MESH_PEERING_CLOSE: 298 if (plid) { 299 ie_len += 2; 300 include_plid = true; 301 } 302 ie_len += 2; /* reason code */ 303 break; 304 default: 305 err = -EINVAL; 306 goto free; 307 } 308 309 if (WARN_ON(skb_tailroom(skb) < 2 + ie_len)) 310 goto free; 311 312 pos = skb_put(skb, 2 + ie_len); 313 *pos++ = WLAN_EID_PEER_MGMT; 314 *pos++ = ie_len; 315 memcpy(pos, &peering_proto, 2); 316 pos += 2; 317 memcpy(pos, &llid, 2); 318 pos += 2; 319 if (include_plid) { 320 memcpy(pos, &plid, 2); 321 pos += 2; 322 } 323 if (action == WLAN_SP_MESH_PEERING_CLOSE) { 324 memcpy(pos, &reason, 2); 325 pos += 2; 326 } 327 328 if (action != WLAN_SP_MESH_PEERING_CLOSE) { 329 if (mesh_add_ht_cap_ie(sdata, skb) || 330 mesh_add_ht_oper_ie(sdata, skb)) 331 goto free; 332 } 333 334 if (mesh_add_vendor_ies(sdata, skb)) 335 goto free; 336 337 ieee80211_tx_skb(sdata, skb); 338 return 0; 339free: 340 kfree_skb(skb); 341 return err; 342} 343 344static void mesh_sta_info_init(struct ieee80211_sub_if_data *sdata, 345 struct sta_info *sta, 346 struct ieee802_11_elems *elems, bool insert) 347{ 348 struct ieee80211_local *local = sdata->local; 349 enum ieee80211_band band = ieee80211_get_sdata_band(sdata); 350 struct ieee80211_supported_band *sband; 351 u32 rates, basic_rates = 0, changed = 0; 352 353 sband = local->hw.wiphy->bands[band]; 354 rates = ieee80211_sta_get_rates(local, elems, band, &basic_rates); 355 356 spin_lock_bh(&sta->lock); 357 sta->last_rx = jiffies; 358 359 /* rates and capabilities don't change during peering */ 360 if (sta->plink_state == NL80211_PLINK_ESTAB) 361 goto out; 362 363 if (sta->sta.supp_rates[band] != rates) 364 changed |= IEEE80211_RC_SUPP_RATES_CHANGED; 365 sta->sta.supp_rates[band] = rates; 366 367 if (ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband, 368 elems->ht_cap_elem, sta)) 369 changed |= IEEE80211_RC_BW_CHANGED; 370 371 /* HT peer is operating 20MHz-only */ 372 if (elems->ht_operation && 373 !(elems->ht_operation->ht_param & 374 IEEE80211_HT_PARAM_CHAN_WIDTH_ANY)) { 375 if (sta->sta.bandwidth != IEEE80211_STA_RX_BW_20) 376 changed |= IEEE80211_RC_BW_CHANGED; 377 sta->sta.bandwidth = IEEE80211_STA_RX_BW_20; 378 } 379 380 if (insert) 381 rate_control_rate_init(sta); 382 else 383 rate_control_rate_update(local, sband, sta, changed); 384out: 385 spin_unlock_bh(&sta->lock); 386} 387 388static struct sta_info * 389__mesh_sta_info_alloc(struct ieee80211_sub_if_data *sdata, u8 *hw_addr) 390{ 391 struct sta_info *sta; 392 393 if (sdata->local->num_sta >= MESH_MAX_PLINKS) 394 return NULL; 395 396 sta = sta_info_alloc(sdata, hw_addr, GFP_KERNEL); 397 if (!sta) 398 return NULL; 399 400 sta->plink_state = NL80211_PLINK_LISTEN; 401 init_timer(&sta->plink_timer); 402 403 sta_info_pre_move_state(sta, IEEE80211_STA_AUTH); 404 sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC); 405 sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED); 406 407 set_sta_flag(sta, WLAN_STA_WME); 408 409 return sta; 410} 411 412static struct sta_info * 413mesh_sta_info_alloc(struct ieee80211_sub_if_data *sdata, u8 *addr, 414 struct ieee802_11_elems *elems) 415{ 416 struct sta_info *sta = NULL; 417 418 /* Userspace handles peer allocation when security is enabled */ 419 if (sdata->u.mesh.security & IEEE80211_MESH_SEC_AUTHED) 420 cfg80211_notify_new_peer_candidate(sdata->dev, addr, 421 elems->ie_start, 422 elems->total_len, 423 GFP_KERNEL); 424 else 425 sta = __mesh_sta_info_alloc(sdata, addr); 426 427 return sta; 428} 429 430/* 431 * mesh_sta_info_get - return mesh sta info entry for @addr. 432 * 433 * @sdata: local meshif 434 * @addr: peer's address 435 * @elems: IEs from beacon or mesh peering frame. 436 * 437 * Return existing or newly allocated sta_info under RCU read lock. 438 * (re)initialize with given IEs. 439 */ 440static struct sta_info * 441mesh_sta_info_get(struct ieee80211_sub_if_data *sdata, 442 u8 *addr, struct ieee802_11_elems *elems) __acquires(RCU) 443{ 444 struct sta_info *sta = NULL; 445 446 rcu_read_lock(); 447 sta = sta_info_get(sdata, addr); 448 if (sta) { 449 mesh_sta_info_init(sdata, sta, elems, false); 450 } else { 451 rcu_read_unlock(); 452 /* can't run atomic */ 453 sta = mesh_sta_info_alloc(sdata, addr, elems); 454 if (!sta) { 455 rcu_read_lock(); 456 return NULL; 457 } 458 459 mesh_sta_info_init(sdata, sta, elems, true); 460 461 if (sta_info_insert_rcu(sta)) 462 return NULL; 463 } 464 465 return sta; 466} 467 468/* 469 * mesh_neighbour_update - update or initialize new mesh neighbor. 470 * 471 * @sdata: local meshif 472 * @addr: peer's address 473 * @elems: IEs from beacon or mesh peering frame 474 * 475 * Initiates peering if appropriate. 476 */ 477void mesh_neighbour_update(struct ieee80211_sub_if_data *sdata, 478 u8 *hw_addr, 479 struct ieee802_11_elems *elems) 480{ 481 struct sta_info *sta; 482 u32 changed = 0; 483 484 sta = mesh_sta_info_get(sdata, hw_addr, elems); 485 if (!sta) 486 goto out; 487 488 if (mesh_peer_accepts_plinks(elems) && 489 sta->plink_state == NL80211_PLINK_LISTEN && 490 sdata->u.mesh.accepting_plinks && 491 sdata->u.mesh.mshcfg.auto_open_plinks && 492 rssi_threshold_check(sta, sdata)) 493 changed = mesh_plink_open(sta); 494 495 ieee80211_mps_frame_release(sta, elems); 496out: 497 rcu_read_unlock(); 498 ieee80211_mbss_info_change_notify(sdata, changed); 499} 500 501static void mesh_plink_timer(unsigned long data) 502{ 503 struct sta_info *sta; 504 __le16 llid, plid, reason; 505 struct ieee80211_sub_if_data *sdata; 506 struct mesh_config *mshcfg; 507 508 /* 509 * This STA is valid because sta_info_destroy() will 510 * del_timer_sync() this timer after having made sure 511 * it cannot be readded (by deleting the plink.) 512 */ 513 sta = (struct sta_info *) data; 514 515 if (sta->sdata->local->quiescing) { 516 sta->plink_timer_was_running = true; 517 return; 518 } 519 520 spin_lock_bh(&sta->lock); 521 if (sta->ignore_plink_timer) { 522 sta->ignore_plink_timer = false; 523 spin_unlock_bh(&sta->lock); 524 return; 525 } 526 mpl_dbg(sta->sdata, 527 "Mesh plink timer for %pM fired on state %d\n", 528 sta->sta.addr, sta->plink_state); 529 reason = 0; 530 llid = sta->llid; 531 plid = sta->plid; 532 sdata = sta->sdata; 533 mshcfg = &sdata->u.mesh.mshcfg; 534 535 switch (sta->plink_state) { 536 case NL80211_PLINK_OPN_RCVD: 537 case NL80211_PLINK_OPN_SNT: 538 /* retry timer */ 539 if (sta->plink_retries < mshcfg->dot11MeshMaxRetries) { 540 u32 rand; 541 mpl_dbg(sta->sdata, 542 "Mesh plink for %pM (retry, timeout): %d %d\n", 543 sta->sta.addr, sta->plink_retries, 544 sta->plink_timeout); 545 get_random_bytes(&rand, sizeof(u32)); 546 sta->plink_timeout = sta->plink_timeout + 547 rand % sta->plink_timeout; 548 ++sta->plink_retries; 549 mod_plink_timer(sta, sta->plink_timeout); 550 spin_unlock_bh(&sta->lock); 551 mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_OPEN, 552 sta->sta.addr, llid, 0, 0); 553 break; 554 } 555 reason = cpu_to_le16(WLAN_REASON_MESH_MAX_RETRIES); 556 /* fall through on else */ 557 case NL80211_PLINK_CNF_RCVD: 558 /* confirm timer */ 559 if (!reason) 560 reason = cpu_to_le16(WLAN_REASON_MESH_CONFIRM_TIMEOUT); 561 sta->plink_state = NL80211_PLINK_HOLDING; 562 mod_plink_timer(sta, mshcfg->dot11MeshHoldingTimeout); 563 spin_unlock_bh(&sta->lock); 564 mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_CLOSE, 565 sta->sta.addr, llid, plid, reason); 566 break; 567 case NL80211_PLINK_HOLDING: 568 /* holding timer */ 569 del_timer(&sta->plink_timer); 570 mesh_plink_fsm_restart(sta); 571 spin_unlock_bh(&sta->lock); 572 break; 573 default: 574 spin_unlock_bh(&sta->lock); 575 break; 576 } 577} 578 579#ifdef CONFIG_PM 580void mesh_plink_quiesce(struct sta_info *sta) 581{ 582 if (!ieee80211_vif_is_mesh(&sta->sdata->vif)) 583 return; 584 585 /* no kernel mesh sta timers have been initialized */ 586 if (sta->sdata->u.mesh.security != IEEE80211_MESH_SEC_NONE) 587 return; 588 589 if (del_timer_sync(&sta->plink_timer)) 590 sta->plink_timer_was_running = true; 591} 592 593void mesh_plink_restart(struct sta_info *sta) 594{ 595 if (sta->plink_timer_was_running) { 596 add_timer(&sta->plink_timer); 597 sta->plink_timer_was_running = false; 598 } 599} 600#endif 601 602static inline void mesh_plink_timer_set(struct sta_info *sta, int timeout) 603{ 604 sta->plink_timer.expires = jiffies + (HZ * timeout / 1000); 605 sta->plink_timer.data = (unsigned long) sta; 606 sta->plink_timer.function = mesh_plink_timer; 607 sta->plink_timeout = timeout; 608 add_timer(&sta->plink_timer); 609} 610 611u32 mesh_plink_open(struct sta_info *sta) 612{ 613 __le16 llid; 614 struct ieee80211_sub_if_data *sdata = sta->sdata; 615 u32 changed; 616 617 if (!test_sta_flag(sta, WLAN_STA_AUTH)) 618 return 0; 619 620 spin_lock_bh(&sta->lock); 621 get_random_bytes(&llid, 2); 622 sta->llid = llid; 623 if (sta->plink_state != NL80211_PLINK_LISTEN && 624 sta->plink_state != NL80211_PLINK_BLOCKED) { 625 spin_unlock_bh(&sta->lock); 626 return 0; 627 } 628 sta->plink_state = NL80211_PLINK_OPN_SNT; 629 mesh_plink_timer_set(sta, sdata->u.mesh.mshcfg.dot11MeshRetryTimeout); 630 spin_unlock_bh(&sta->lock); 631 mpl_dbg(sdata, 632 "Mesh plink: starting establishment with %pM\n", 633 sta->sta.addr); 634 635 /* set the non-peer mode to active during peering */ 636 changed = ieee80211_mps_local_status_update(sdata); 637 638 mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_OPEN, 639 sta->sta.addr, llid, 0, 0); 640 return changed; 641} 642 643u32 mesh_plink_block(struct sta_info *sta) 644{ 645 u32 changed; 646 647 spin_lock_bh(&sta->lock); 648 changed = __mesh_plink_deactivate(sta); 649 sta->plink_state = NL80211_PLINK_BLOCKED; 650 spin_unlock_bh(&sta->lock); 651 652 return changed; 653} 654 655 656void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata, 657 struct ieee80211_mgmt *mgmt, size_t len, 658 struct ieee80211_rx_status *rx_status) 659{ 660 struct mesh_config *mshcfg = &sdata->u.mesh.mshcfg; 661 struct ieee802_11_elems elems; 662 struct sta_info *sta; 663 enum plink_event event; 664 enum ieee80211_self_protected_actioncode ftype; 665 size_t baselen; 666 bool matches_local = true; 667 u8 ie_len; 668 u8 *baseaddr; 669 u32 changed = 0; 670 __le16 plid, llid, reason; 671 static const char * const mplstates[] = { 672 [NL80211_PLINK_LISTEN] = "LISTEN", 673 [NL80211_PLINK_OPN_SNT] = "OPN-SNT", 674 [NL80211_PLINK_OPN_RCVD] = "OPN-RCVD", 675 [NL80211_PLINK_CNF_RCVD] = "CNF_RCVD", 676 [NL80211_PLINK_ESTAB] = "ESTAB", 677 [NL80211_PLINK_HOLDING] = "HOLDING", 678 [NL80211_PLINK_BLOCKED] = "BLOCKED" 679 }; 680 681 /* need action_code, aux */ 682 if (len < IEEE80211_MIN_ACTION_SIZE + 3) 683 return; 684 685 if (is_multicast_ether_addr(mgmt->da)) { 686 mpl_dbg(sdata, 687 "Mesh plink: ignore frame from multicast address\n"); 688 return; 689 } 690 691 baseaddr = mgmt->u.action.u.self_prot.variable; 692 baselen = (u8 *) mgmt->u.action.u.self_prot.variable - (u8 *) mgmt; 693 if (mgmt->u.action.u.self_prot.action_code == 694 WLAN_SP_MESH_PEERING_CONFIRM) { 695 baseaddr += 4; 696 baselen += 4; 697 } 698 ieee802_11_parse_elems(baseaddr, len - baselen, &elems); 699 700 if (!elems.peering) { 701 mpl_dbg(sdata, 702 "Mesh plink: missing necessary peer link ie\n"); 703 return; 704 } 705 706 if (elems.rsn_len && 707 sdata->u.mesh.security == IEEE80211_MESH_SEC_NONE) { 708 mpl_dbg(sdata, 709 "Mesh plink: can't establish link with secure peer\n"); 710 return; 711 } 712 713 ftype = mgmt->u.action.u.self_prot.action_code; 714 ie_len = elems.peering_len; 715 if ((ftype == WLAN_SP_MESH_PEERING_OPEN && ie_len != 4) || 716 (ftype == WLAN_SP_MESH_PEERING_CONFIRM && ie_len != 6) || 717 (ftype == WLAN_SP_MESH_PEERING_CLOSE && ie_len != 6 718 && ie_len != 8)) { 719 mpl_dbg(sdata, 720 "Mesh plink: incorrect plink ie length %d %d\n", 721 ftype, ie_len); 722 return; 723 } 724 725 if (ftype != WLAN_SP_MESH_PEERING_CLOSE && 726 (!elems.mesh_id || !elems.mesh_config)) { 727 mpl_dbg(sdata, "Mesh plink: missing necessary ie\n"); 728 return; 729 } 730 /* Note the lines below are correct, the llid in the frame is the plid 731 * from the point of view of this host. 732 */ 733 memcpy(&plid, PLINK_GET_LLID(elems.peering), 2); 734 if (ftype == WLAN_SP_MESH_PEERING_CONFIRM || 735 (ftype == WLAN_SP_MESH_PEERING_CLOSE && ie_len == 8)) 736 memcpy(&llid, PLINK_GET_PLID(elems.peering), 2); 737 738 /* WARNING: Only for sta pointer, is dropped & re-acquired */ 739 rcu_read_lock(); 740 741 sta = sta_info_get(sdata, mgmt->sa); 742 if (!sta && ftype != WLAN_SP_MESH_PEERING_OPEN) { 743 mpl_dbg(sdata, "Mesh plink: cls or cnf from unknown peer\n"); 744 rcu_read_unlock(); 745 return; 746 } 747 748 if (ftype == WLAN_SP_MESH_PEERING_OPEN && 749 !rssi_threshold_check(sta, sdata)) { 750 mpl_dbg(sdata, "Mesh plink: %pM does not meet rssi threshold\n", 751 mgmt->sa); 752 rcu_read_unlock(); 753 return; 754 } 755 756 if (sta && !test_sta_flag(sta, WLAN_STA_AUTH)) { 757 mpl_dbg(sdata, "Mesh plink: Action frame from non-authed peer\n"); 758 rcu_read_unlock(); 759 return; 760 } 761 762 if (sta && sta->plink_state == NL80211_PLINK_BLOCKED) { 763 rcu_read_unlock(); 764 return; 765 } 766 767 /* Now we will figure out the appropriate event... */ 768 event = PLINK_UNDEFINED; 769 if (ftype != WLAN_SP_MESH_PEERING_CLOSE && 770 !mesh_matches_local(sdata, &elems)) { 771 matches_local = false; 772 switch (ftype) { 773 case WLAN_SP_MESH_PEERING_OPEN: 774 event = OPN_RJCT; 775 break; 776 case WLAN_SP_MESH_PEERING_CONFIRM: 777 event = CNF_RJCT; 778 break; 779 default: 780 break; 781 } 782 } 783 784 if (!sta && !matches_local) { 785 rcu_read_unlock(); 786 reason = cpu_to_le16(WLAN_REASON_MESH_CONFIG); 787 llid = 0; 788 mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_CLOSE, 789 mgmt->sa, llid, plid, reason); 790 return; 791 } else if (!sta) { 792 /* ftype == WLAN_SP_MESH_PEERING_OPEN */ 793 if (!mesh_plink_free_count(sdata)) { 794 mpl_dbg(sdata, "Mesh plink error: no more free plinks\n"); 795 rcu_read_unlock(); 796 return; 797 } 798 event = OPN_ACPT; 799 } else if (matches_local) { 800 switch (ftype) { 801 case WLAN_SP_MESH_PEERING_OPEN: 802 if (!mesh_plink_free_count(sdata) || 803 (sta->plid && sta->plid != plid)) 804 event = OPN_IGNR; 805 else 806 event = OPN_ACPT; 807 break; 808 case WLAN_SP_MESH_PEERING_CONFIRM: 809 if (!mesh_plink_free_count(sdata) || 810 (sta->llid != llid || sta->plid != plid)) 811 event = CNF_IGNR; 812 else 813 event = CNF_ACPT; 814 break; 815 case WLAN_SP_MESH_PEERING_CLOSE: 816 if (sta->plink_state == NL80211_PLINK_ESTAB) 817 /* Do not check for llid or plid. This does not 818 * follow the standard but since multiple plinks 819 * per sta are not supported, it is necessary in 820 * order to avoid a livelock when MP A sees an 821 * establish peer link to MP B but MP B does not 822 * see it. This can be caused by a timeout in 823 * B's peer link establishment or B beign 824 * restarted. 825 */ 826 event = CLS_ACPT; 827 else if (sta->plid != plid) 828 event = CLS_IGNR; 829 else if (ie_len == 7 && sta->llid != llid) 830 event = CLS_IGNR; 831 else 832 event = CLS_ACPT; 833 break; 834 default: 835 mpl_dbg(sdata, "Mesh plink: unknown frame subtype\n"); 836 rcu_read_unlock(); 837 return; 838 } 839 } 840 841 if (event == OPN_ACPT) { 842 rcu_read_unlock(); 843 /* allocate sta entry if necessary and update info */ 844 sta = mesh_sta_info_get(sdata, mgmt->sa, &elems); 845 if (!sta) { 846 mpl_dbg(sdata, "Mesh plink: failed to init peer!\n"); 847 rcu_read_unlock(); 848 return; 849 } 850 } 851 852 mpl_dbg(sdata, 853 "Mesh plink (peer, state, llid, plid, event): %pM %s %d %d %d\n", 854 mgmt->sa, mplstates[sta->plink_state], 855 le16_to_cpu(sta->llid), le16_to_cpu(sta->plid), 856 event); 857 reason = 0; 858 spin_lock_bh(&sta->lock); 859 switch (sta->plink_state) { 860 /* spin_unlock as soon as state is updated at each case */ 861 case NL80211_PLINK_LISTEN: 862 switch (event) { 863 case CLS_ACPT: 864 mesh_plink_fsm_restart(sta); 865 spin_unlock_bh(&sta->lock); 866 break; 867 case OPN_ACPT: 868 sta->plink_state = NL80211_PLINK_OPN_RCVD; 869 sta->plid = plid; 870 get_random_bytes(&llid, 2); 871 sta->llid = llid; 872 mesh_plink_timer_set(sta, 873 mshcfg->dot11MeshRetryTimeout); 874 875 /* set the non-peer mode to active during peering */ 876 changed |= ieee80211_mps_local_status_update(sdata); 877 878 spin_unlock_bh(&sta->lock); 879 mesh_plink_frame_tx(sdata, 880 WLAN_SP_MESH_PEERING_OPEN, 881 sta->sta.addr, llid, 0, 0); 882 mesh_plink_frame_tx(sdata, 883 WLAN_SP_MESH_PEERING_CONFIRM, 884 sta->sta.addr, llid, plid, 0); 885 break; 886 default: 887 spin_unlock_bh(&sta->lock); 888 break; 889 } 890 break; 891 892 case NL80211_PLINK_OPN_SNT: 893 switch (event) { 894 case OPN_RJCT: 895 case CNF_RJCT: 896 reason = cpu_to_le16(WLAN_REASON_MESH_CONFIG); 897 case CLS_ACPT: 898 if (!reason) 899 reason = cpu_to_le16(WLAN_REASON_MESH_CLOSE); 900 sta->reason = reason; 901 sta->plink_state = NL80211_PLINK_HOLDING; 902 if (!mod_plink_timer(sta, 903 mshcfg->dot11MeshHoldingTimeout)) 904 sta->ignore_plink_timer = true; 905 906 llid = sta->llid; 907 spin_unlock_bh(&sta->lock); 908 mesh_plink_frame_tx(sdata, 909 WLAN_SP_MESH_PEERING_CLOSE, 910 sta->sta.addr, llid, plid, reason); 911 break; 912 case OPN_ACPT: 913 /* retry timer is left untouched */ 914 sta->plink_state = NL80211_PLINK_OPN_RCVD; 915 sta->plid = plid; 916 llid = sta->llid; 917 spin_unlock_bh(&sta->lock); 918 mesh_plink_frame_tx(sdata, 919 WLAN_SP_MESH_PEERING_CONFIRM, 920 sta->sta.addr, llid, plid, 0); 921 break; 922 case CNF_ACPT: 923 sta->plink_state = NL80211_PLINK_CNF_RCVD; 924 if (!mod_plink_timer(sta, 925 mshcfg->dot11MeshConfirmTimeout)) 926 sta->ignore_plink_timer = true; 927 928 spin_unlock_bh(&sta->lock); 929 break; 930 default: 931 spin_unlock_bh(&sta->lock); 932 break; 933 } 934 break; 935 936 case NL80211_PLINK_OPN_RCVD: 937 switch (event) { 938 case OPN_RJCT: 939 case CNF_RJCT: 940 reason = cpu_to_le16(WLAN_REASON_MESH_CONFIG); 941 case CLS_ACPT: 942 if (!reason) 943 reason = cpu_to_le16(WLAN_REASON_MESH_CLOSE); 944 sta->reason = reason; 945 sta->plink_state = NL80211_PLINK_HOLDING; 946 if (!mod_plink_timer(sta, 947 mshcfg->dot11MeshHoldingTimeout)) 948 sta->ignore_plink_timer = true; 949 950 llid = sta->llid; 951 spin_unlock_bh(&sta->lock); 952 mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_CLOSE, 953 sta->sta.addr, llid, plid, reason); 954 break; 955 case OPN_ACPT: 956 llid = sta->llid; 957 spin_unlock_bh(&sta->lock); 958 mesh_plink_frame_tx(sdata, 959 WLAN_SP_MESH_PEERING_CONFIRM, 960 sta->sta.addr, llid, plid, 0); 961 break; 962 case CNF_ACPT: 963 del_timer(&sta->plink_timer); 964 sta->plink_state = NL80211_PLINK_ESTAB; 965 spin_unlock_bh(&sta->lock); 966 changed |= mesh_plink_inc_estab_count(sdata); 967 changed |= mesh_set_ht_prot_mode(sdata); 968 changed |= mesh_set_short_slot_time(sdata); 969 mpl_dbg(sdata, "Mesh plink with %pM ESTABLISHED\n", 970 sta->sta.addr); 971 ieee80211_mps_sta_status_update(sta); 972 changed |= ieee80211_mps_set_sta_local_pm(sta, 973 mshcfg->power_mode); 974 break; 975 default: 976 spin_unlock_bh(&sta->lock); 977 break; 978 } 979 break; 980 981 case NL80211_PLINK_CNF_RCVD: 982 switch (event) { 983 case OPN_RJCT: 984 case CNF_RJCT: 985 reason = cpu_to_le16(WLAN_REASON_MESH_CONFIG); 986 case CLS_ACPT: 987 if (!reason) 988 reason = cpu_to_le16(WLAN_REASON_MESH_CLOSE); 989 sta->reason = reason; 990 sta->plink_state = NL80211_PLINK_HOLDING; 991 if (!mod_plink_timer(sta, 992 mshcfg->dot11MeshHoldingTimeout)) 993 sta->ignore_plink_timer = true; 994 995 llid = sta->llid; 996 spin_unlock_bh(&sta->lock); 997 mesh_plink_frame_tx(sdata, 998 WLAN_SP_MESH_PEERING_CLOSE, 999 sta->sta.addr, llid, plid, reason); 1000 break; 1001 case OPN_ACPT: 1002 del_timer(&sta->plink_timer); 1003 sta->plink_state = NL80211_PLINK_ESTAB; 1004 spin_unlock_bh(&sta->lock); 1005 changed |= mesh_plink_inc_estab_count(sdata); 1006 changed |= mesh_set_ht_prot_mode(sdata); 1007 changed |= mesh_set_short_slot_time(sdata); 1008 mpl_dbg(sdata, "Mesh plink with %pM ESTABLISHED\n", 1009 sta->sta.addr); 1010 mesh_plink_frame_tx(sdata, 1011 WLAN_SP_MESH_PEERING_CONFIRM, 1012 sta->sta.addr, llid, plid, 0); 1013 ieee80211_mps_sta_status_update(sta); 1014 changed |= ieee80211_mps_set_sta_local_pm(sta, 1015 mshcfg->power_mode); 1016 break; 1017 default: 1018 spin_unlock_bh(&sta->lock); 1019 break; 1020 } 1021 break; 1022 1023 case NL80211_PLINK_ESTAB: 1024 switch (event) { 1025 case CLS_ACPT: 1026 reason = cpu_to_le16(WLAN_REASON_MESH_CLOSE); 1027 sta->reason = reason; 1028 changed |= __mesh_plink_deactivate(sta); 1029 sta->plink_state = NL80211_PLINK_HOLDING; 1030 llid = sta->llid; 1031 mod_plink_timer(sta, mshcfg->dot11MeshHoldingTimeout); 1032 spin_unlock_bh(&sta->lock); 1033 changed |= mesh_set_ht_prot_mode(sdata); 1034 changed |= mesh_set_short_slot_time(sdata); 1035 mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_CLOSE, 1036 sta->sta.addr, llid, plid, reason); 1037 break; 1038 case OPN_ACPT: 1039 llid = sta->llid; 1040 spin_unlock_bh(&sta->lock); 1041 mesh_plink_frame_tx(sdata, 1042 WLAN_SP_MESH_PEERING_CONFIRM, 1043 sta->sta.addr, llid, plid, 0); 1044 break; 1045 default: 1046 spin_unlock_bh(&sta->lock); 1047 break; 1048 } 1049 break; 1050 case NL80211_PLINK_HOLDING: 1051 switch (event) { 1052 case CLS_ACPT: 1053 if (del_timer(&sta->plink_timer)) 1054 sta->ignore_plink_timer = 1; 1055 mesh_plink_fsm_restart(sta); 1056 spin_unlock_bh(&sta->lock); 1057 break; 1058 case OPN_ACPT: 1059 case CNF_ACPT: 1060 case OPN_RJCT: 1061 case CNF_RJCT: 1062 llid = sta->llid; 1063 reason = sta->reason; 1064 spin_unlock_bh(&sta->lock); 1065 mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_CLOSE, 1066 sta->sta.addr, llid, plid, reason); 1067 break; 1068 default: 1069 spin_unlock_bh(&sta->lock); 1070 } 1071 break; 1072 default: 1073 /* should not get here, PLINK_BLOCKED is dealt with at the 1074 * beginning of the function 1075 */ 1076 spin_unlock_bh(&sta->lock); 1077 break; 1078 } 1079 1080 rcu_read_unlock(); 1081 1082 if (changed) 1083 ieee80211_mbss_info_change_notify(sdata, changed); 1084} 1085