mesh_plink.c revision 8d61ffa5e01c5f676431d12caba17db164a48a86
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 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 50static 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 62static 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 */ 73static 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 */ 90static 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 130out: 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 */ 150static 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 */ 208static 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 */ 231u32 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 247static 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; 361free: 362 kfree_skb(skb); 363 return err; 364} 365 366static 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); 406out: 407 spin_unlock_bh(&sta->lock); 408} 409 410static 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; 423 424 sta_info_pre_move_state(sta, IEEE80211_STA_AUTH); 425 sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC); 426 sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED); 427 428 set_sta_flag(sta, WLAN_STA_WME); 429 430 return sta; 431} 432 433static struct sta_info * 434mesh_sta_info_alloc(struct ieee80211_sub_if_data *sdata, u8 *addr, 435 struct ieee802_11_elems *elems) 436{ 437 struct sta_info *sta = NULL; 438 439 /* Userspace handles station allocation */ 440 if (sdata->u.mesh.user_mpm || 441 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 */ 462static struct sta_info * 463mesh_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 */ 499void 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); 518out: 519 rcu_read_unlock(); 520 sdata_lock(sdata); 521 ieee80211_mbss_info_change_notify(sdata, changed); 522 sdata_unlock(sdata); 523} 524 525static void mesh_plink_timer(unsigned long data) 526{ 527 struct sta_info *sta; 528 __le16 llid, plid, reason; 529 struct ieee80211_sub_if_data *sdata; 530 struct mesh_config *mshcfg; 531 532 /* 533 * This STA is valid because sta_info_destroy() will 534 * del_timer_sync() this timer after having made sure 535 * it cannot be readded (by deleting the plink.) 536 */ 537 sta = (struct sta_info *) data; 538 539 if (sta->sdata->local->quiescing) 540 return; 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 %s\n", 550 sta->sta.addr, mplstates[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 601static inline void mesh_plink_timer_set(struct sta_info *sta, int timeout) 602{ 603 sta->plink_timer.expires = jiffies + (HZ * timeout / 1000); 604 sta->plink_timer.data = (unsigned long) sta; 605 sta->plink_timer.function = mesh_plink_timer; 606 sta->plink_timeout = timeout; 607 add_timer(&sta->plink_timer); 608} 609 610u32 mesh_plink_open(struct sta_info *sta) 611{ 612 __le16 llid; 613 struct ieee80211_sub_if_data *sdata = sta->sdata; 614 u32 changed; 615 616 if (!test_sta_flag(sta, WLAN_STA_AUTH)) 617 return 0; 618 619 spin_lock_bh(&sta->lock); 620 get_random_bytes(&llid, 2); 621 sta->llid = llid; 622 if (sta->plink_state != NL80211_PLINK_LISTEN && 623 sta->plink_state != NL80211_PLINK_BLOCKED) { 624 spin_unlock_bh(&sta->lock); 625 return 0; 626 } 627 sta->plink_state = NL80211_PLINK_OPN_SNT; 628 mesh_plink_timer_set(sta, sdata->u.mesh.mshcfg.dot11MeshRetryTimeout); 629 spin_unlock_bh(&sta->lock); 630 mpl_dbg(sdata, 631 "Mesh plink: starting establishment with %pM\n", 632 sta->sta.addr); 633 634 /* set the non-peer mode to active during peering */ 635 changed = ieee80211_mps_local_status_update(sdata); 636 637 mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_OPEN, 638 sta->sta.addr, llid, 0, 0); 639 return changed; 640} 641 642u32 mesh_plink_block(struct sta_info *sta) 643{ 644 u32 changed; 645 646 spin_lock_bh(&sta->lock); 647 changed = __mesh_plink_deactivate(sta); 648 sta->plink_state = NL80211_PLINK_BLOCKED; 649 spin_unlock_bh(&sta->lock); 650 651 return changed; 652} 653 654 655void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata, 656 struct ieee80211_mgmt *mgmt, size_t len, 657 struct ieee80211_rx_status *rx_status) 658{ 659 struct mesh_config *mshcfg = &sdata->u.mesh.mshcfg; 660 struct ieee802_11_elems elems; 661 struct sta_info *sta; 662 enum plink_event event; 663 enum ieee80211_self_protected_actioncode ftype; 664 size_t baselen; 665 bool matches_local = true; 666 u8 ie_len; 667 u8 *baseaddr; 668 u32 changed = 0; 669 __le16 plid, llid, reason; 670 671 /* need action_code, aux */ 672 if (len < IEEE80211_MIN_ACTION_SIZE + 3) 673 return; 674 675 if (sdata->u.mesh.user_mpm) 676 /* userspace must register for these */ 677 return; 678 679 if (is_multicast_ether_addr(mgmt->da)) { 680 mpl_dbg(sdata, 681 "Mesh plink: ignore frame from multicast address\n"); 682 return; 683 } 684 685 baseaddr = mgmt->u.action.u.self_prot.variable; 686 baselen = (u8 *) mgmt->u.action.u.self_prot.variable - (u8 *) mgmt; 687 if (mgmt->u.action.u.self_prot.action_code == 688 WLAN_SP_MESH_PEERING_CONFIRM) { 689 baseaddr += 4; 690 baselen += 4; 691 } 692 ieee802_11_parse_elems(baseaddr, len - baselen, true, &elems); 693 694 if (!elems.peering) { 695 mpl_dbg(sdata, 696 "Mesh plink: missing necessary peer link ie\n"); 697 return; 698 } 699 700 if (elems.rsn_len && 701 sdata->u.mesh.security == IEEE80211_MESH_SEC_NONE) { 702 mpl_dbg(sdata, 703 "Mesh plink: can't establish link with secure peer\n"); 704 return; 705 } 706 707 ftype = mgmt->u.action.u.self_prot.action_code; 708 ie_len = elems.peering_len; 709 if ((ftype == WLAN_SP_MESH_PEERING_OPEN && ie_len != 4) || 710 (ftype == WLAN_SP_MESH_PEERING_CONFIRM && ie_len != 6) || 711 (ftype == WLAN_SP_MESH_PEERING_CLOSE && ie_len != 6 712 && ie_len != 8)) { 713 mpl_dbg(sdata, 714 "Mesh plink: incorrect plink ie length %d %d\n", 715 ftype, ie_len); 716 return; 717 } 718 719 if (ftype != WLAN_SP_MESH_PEERING_CLOSE && 720 (!elems.mesh_id || !elems.mesh_config)) { 721 mpl_dbg(sdata, "Mesh plink: missing necessary ie\n"); 722 return; 723 } 724 /* Note the lines below are correct, the llid in the frame is the plid 725 * from the point of view of this host. 726 */ 727 memcpy(&plid, PLINK_GET_LLID(elems.peering), 2); 728 if (ftype == WLAN_SP_MESH_PEERING_CONFIRM || 729 (ftype == WLAN_SP_MESH_PEERING_CLOSE && ie_len == 8)) 730 memcpy(&llid, PLINK_GET_PLID(elems.peering), 2); 731 732 /* WARNING: Only for sta pointer, is dropped & re-acquired */ 733 rcu_read_lock(); 734 735 sta = sta_info_get(sdata, mgmt->sa); 736 if (!sta && ftype != WLAN_SP_MESH_PEERING_OPEN) { 737 mpl_dbg(sdata, "Mesh plink: cls or cnf from unknown peer\n"); 738 rcu_read_unlock(); 739 return; 740 } 741 742 if (ftype == WLAN_SP_MESH_PEERING_OPEN && 743 !rssi_threshold_check(sta, sdata)) { 744 mpl_dbg(sdata, "Mesh plink: %pM does not meet rssi threshold\n", 745 mgmt->sa); 746 rcu_read_unlock(); 747 return; 748 } 749 750 if (sta && !test_sta_flag(sta, WLAN_STA_AUTH)) { 751 mpl_dbg(sdata, "Mesh plink: Action frame from non-authed peer\n"); 752 rcu_read_unlock(); 753 return; 754 } 755 756 if (sta && sta->plink_state == NL80211_PLINK_BLOCKED) { 757 rcu_read_unlock(); 758 return; 759 } 760 761 /* Now we will figure out the appropriate event... */ 762 event = PLINK_UNDEFINED; 763 if (ftype != WLAN_SP_MESH_PEERING_CLOSE && 764 !mesh_matches_local(sdata, &elems)) { 765 matches_local = false; 766 switch (ftype) { 767 case WLAN_SP_MESH_PEERING_OPEN: 768 event = OPN_RJCT; 769 break; 770 case WLAN_SP_MESH_PEERING_CONFIRM: 771 event = CNF_RJCT; 772 break; 773 default: 774 break; 775 } 776 } 777 778 if (!sta && !matches_local) { 779 rcu_read_unlock(); 780 reason = cpu_to_le16(WLAN_REASON_MESH_CONFIG); 781 llid = 0; 782 mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_CLOSE, 783 mgmt->sa, llid, plid, reason); 784 return; 785 } else if (!sta) { 786 /* ftype == WLAN_SP_MESH_PEERING_OPEN */ 787 if (!mesh_plink_free_count(sdata)) { 788 mpl_dbg(sdata, "Mesh plink error: no more free plinks\n"); 789 rcu_read_unlock(); 790 return; 791 } 792 event = OPN_ACPT; 793 } else if (matches_local) { 794 switch (ftype) { 795 case WLAN_SP_MESH_PEERING_OPEN: 796 if (!mesh_plink_free_count(sdata) || 797 (sta->plid && sta->plid != plid)) 798 event = OPN_IGNR; 799 else 800 event = OPN_ACPT; 801 break; 802 case WLAN_SP_MESH_PEERING_CONFIRM: 803 if (!mesh_plink_free_count(sdata) || 804 (sta->llid != llid || sta->plid != plid)) 805 event = CNF_IGNR; 806 else 807 event = CNF_ACPT; 808 break; 809 case WLAN_SP_MESH_PEERING_CLOSE: 810 if (sta->plink_state == NL80211_PLINK_ESTAB) 811 /* Do not check for llid or plid. This does not 812 * follow the standard but since multiple plinks 813 * per sta are not supported, it is necessary in 814 * order to avoid a livelock when MP A sees an 815 * establish peer link to MP B but MP B does not 816 * see it. This can be caused by a timeout in 817 * B's peer link establishment or B beign 818 * restarted. 819 */ 820 event = CLS_ACPT; 821 else if (sta->plid != plid) 822 event = CLS_IGNR; 823 else if (ie_len == 7 && sta->llid != llid) 824 event = CLS_IGNR; 825 else 826 event = CLS_ACPT; 827 break; 828 default: 829 mpl_dbg(sdata, "Mesh plink: unknown frame subtype\n"); 830 rcu_read_unlock(); 831 return; 832 } 833 } 834 835 if (event == OPN_ACPT) { 836 rcu_read_unlock(); 837 /* allocate sta entry if necessary and update info */ 838 sta = mesh_sta_info_get(sdata, mgmt->sa, &elems); 839 if (!sta) { 840 mpl_dbg(sdata, "Mesh plink: failed to init peer!\n"); 841 rcu_read_unlock(); 842 return; 843 } 844 } 845 846 mpl_dbg(sdata, "peer %pM in state %s got event %s\n", mgmt->sa, 847 mplstates[sta->plink_state], mplevents[event]); 848 reason = 0; 849 spin_lock_bh(&sta->lock); 850 switch (sta->plink_state) { 851 /* spin_unlock as soon as state is updated at each case */ 852 case NL80211_PLINK_LISTEN: 853 switch (event) { 854 case CLS_ACPT: 855 mesh_plink_fsm_restart(sta); 856 spin_unlock_bh(&sta->lock); 857 break; 858 case OPN_ACPT: 859 sta->plink_state = NL80211_PLINK_OPN_RCVD; 860 sta->plid = plid; 861 get_random_bytes(&llid, 2); 862 sta->llid = llid; 863 mesh_plink_timer_set(sta, 864 mshcfg->dot11MeshRetryTimeout); 865 866 /* set the non-peer mode to active during peering */ 867 changed |= ieee80211_mps_local_status_update(sdata); 868 869 spin_unlock_bh(&sta->lock); 870 mesh_plink_frame_tx(sdata, 871 WLAN_SP_MESH_PEERING_OPEN, 872 sta->sta.addr, llid, 0, 0); 873 mesh_plink_frame_tx(sdata, 874 WLAN_SP_MESH_PEERING_CONFIRM, 875 sta->sta.addr, llid, plid, 0); 876 break; 877 default: 878 spin_unlock_bh(&sta->lock); 879 break; 880 } 881 break; 882 883 case NL80211_PLINK_OPN_SNT: 884 switch (event) { 885 case OPN_RJCT: 886 case CNF_RJCT: 887 reason = cpu_to_le16(WLAN_REASON_MESH_CONFIG); 888 case CLS_ACPT: 889 if (!reason) 890 reason = cpu_to_le16(WLAN_REASON_MESH_CLOSE); 891 sta->reason = reason; 892 sta->plink_state = NL80211_PLINK_HOLDING; 893 if (!mod_plink_timer(sta, 894 mshcfg->dot11MeshHoldingTimeout)) 895 sta->ignore_plink_timer = true; 896 897 llid = sta->llid; 898 spin_unlock_bh(&sta->lock); 899 mesh_plink_frame_tx(sdata, 900 WLAN_SP_MESH_PEERING_CLOSE, 901 sta->sta.addr, llid, plid, reason); 902 break; 903 case OPN_ACPT: 904 /* retry timer is left untouched */ 905 sta->plink_state = NL80211_PLINK_OPN_RCVD; 906 sta->plid = plid; 907 llid = sta->llid; 908 spin_unlock_bh(&sta->lock); 909 mesh_plink_frame_tx(sdata, 910 WLAN_SP_MESH_PEERING_CONFIRM, 911 sta->sta.addr, llid, plid, 0); 912 break; 913 case CNF_ACPT: 914 sta->plink_state = NL80211_PLINK_CNF_RCVD; 915 if (!mod_plink_timer(sta, 916 mshcfg->dot11MeshConfirmTimeout)) 917 sta->ignore_plink_timer = true; 918 919 spin_unlock_bh(&sta->lock); 920 break; 921 default: 922 spin_unlock_bh(&sta->lock); 923 break; 924 } 925 break; 926 927 case NL80211_PLINK_OPN_RCVD: 928 switch (event) { 929 case OPN_RJCT: 930 case CNF_RJCT: 931 reason = cpu_to_le16(WLAN_REASON_MESH_CONFIG); 932 case CLS_ACPT: 933 if (!reason) 934 reason = cpu_to_le16(WLAN_REASON_MESH_CLOSE); 935 sta->reason = reason; 936 sta->plink_state = NL80211_PLINK_HOLDING; 937 if (!mod_plink_timer(sta, 938 mshcfg->dot11MeshHoldingTimeout)) 939 sta->ignore_plink_timer = true; 940 941 llid = sta->llid; 942 spin_unlock_bh(&sta->lock); 943 mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_CLOSE, 944 sta->sta.addr, llid, plid, reason); 945 break; 946 case OPN_ACPT: 947 llid = sta->llid; 948 spin_unlock_bh(&sta->lock); 949 mesh_plink_frame_tx(sdata, 950 WLAN_SP_MESH_PEERING_CONFIRM, 951 sta->sta.addr, llid, plid, 0); 952 break; 953 case CNF_ACPT: 954 del_timer(&sta->plink_timer); 955 sta->plink_state = NL80211_PLINK_ESTAB; 956 spin_unlock_bh(&sta->lock); 957 changed |= mesh_plink_inc_estab_count(sdata); 958 changed |= mesh_set_ht_prot_mode(sdata); 959 changed |= mesh_set_short_slot_time(sdata); 960 mpl_dbg(sdata, "Mesh plink with %pM ESTABLISHED\n", 961 sta->sta.addr); 962 ieee80211_mps_sta_status_update(sta); 963 changed |= ieee80211_mps_set_sta_local_pm(sta, 964 mshcfg->power_mode); 965 break; 966 default: 967 spin_unlock_bh(&sta->lock); 968 break; 969 } 970 break; 971 972 case NL80211_PLINK_CNF_RCVD: 973 switch (event) { 974 case OPN_RJCT: 975 case CNF_RJCT: 976 reason = cpu_to_le16(WLAN_REASON_MESH_CONFIG); 977 case CLS_ACPT: 978 if (!reason) 979 reason = cpu_to_le16(WLAN_REASON_MESH_CLOSE); 980 sta->reason = reason; 981 sta->plink_state = NL80211_PLINK_HOLDING; 982 if (!mod_plink_timer(sta, 983 mshcfg->dot11MeshHoldingTimeout)) 984 sta->ignore_plink_timer = true; 985 986 llid = sta->llid; 987 spin_unlock_bh(&sta->lock); 988 mesh_plink_frame_tx(sdata, 989 WLAN_SP_MESH_PEERING_CLOSE, 990 sta->sta.addr, llid, plid, reason); 991 break; 992 case OPN_ACPT: 993 del_timer(&sta->plink_timer); 994 sta->plink_state = NL80211_PLINK_ESTAB; 995 spin_unlock_bh(&sta->lock); 996 changed |= mesh_plink_inc_estab_count(sdata); 997 changed |= mesh_set_ht_prot_mode(sdata); 998 changed |= mesh_set_short_slot_time(sdata); 999 mpl_dbg(sdata, "Mesh plink with %pM ESTABLISHED\n", 1000 sta->sta.addr); 1001 mesh_plink_frame_tx(sdata, 1002 WLAN_SP_MESH_PEERING_CONFIRM, 1003 sta->sta.addr, llid, plid, 0); 1004 ieee80211_mps_sta_status_update(sta); 1005 changed |= ieee80211_mps_set_sta_local_pm(sta, 1006 mshcfg->power_mode); 1007 break; 1008 default: 1009 spin_unlock_bh(&sta->lock); 1010 break; 1011 } 1012 break; 1013 1014 case NL80211_PLINK_ESTAB: 1015 switch (event) { 1016 case CLS_ACPT: 1017 reason = cpu_to_le16(WLAN_REASON_MESH_CLOSE); 1018 sta->reason = reason; 1019 changed |= __mesh_plink_deactivate(sta); 1020 sta->plink_state = NL80211_PLINK_HOLDING; 1021 llid = sta->llid; 1022 mod_plink_timer(sta, mshcfg->dot11MeshHoldingTimeout); 1023 spin_unlock_bh(&sta->lock); 1024 changed |= mesh_set_ht_prot_mode(sdata); 1025 changed |= mesh_set_short_slot_time(sdata); 1026 mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_CLOSE, 1027 sta->sta.addr, llid, plid, reason); 1028 break; 1029 case OPN_ACPT: 1030 llid = sta->llid; 1031 spin_unlock_bh(&sta->lock); 1032 mesh_plink_frame_tx(sdata, 1033 WLAN_SP_MESH_PEERING_CONFIRM, 1034 sta->sta.addr, llid, plid, 0); 1035 break; 1036 default: 1037 spin_unlock_bh(&sta->lock); 1038 break; 1039 } 1040 break; 1041 case NL80211_PLINK_HOLDING: 1042 switch (event) { 1043 case CLS_ACPT: 1044 if (del_timer(&sta->plink_timer)) 1045 sta->ignore_plink_timer = 1; 1046 mesh_plink_fsm_restart(sta); 1047 spin_unlock_bh(&sta->lock); 1048 break; 1049 case OPN_ACPT: 1050 case CNF_ACPT: 1051 case OPN_RJCT: 1052 case CNF_RJCT: 1053 llid = sta->llid; 1054 reason = sta->reason; 1055 spin_unlock_bh(&sta->lock); 1056 mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_CLOSE, 1057 sta->sta.addr, llid, plid, reason); 1058 break; 1059 default: 1060 spin_unlock_bh(&sta->lock); 1061 } 1062 break; 1063 default: 1064 /* should not get here, PLINK_BLOCKED is dealt with at the 1065 * beginning of the function 1066 */ 1067 spin_unlock_bh(&sta->lock); 1068 break; 1069 } 1070 1071 rcu_read_unlock(); 1072 1073 if (changed) { 1074 sdata_lock(sdata); 1075 ieee80211_mbss_info_change_notify(sdata, changed); 1076 sdata_unlock(sdata); 1077 } 1078} 1079