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 station allocation */ 441 if (sdata->u.mesh.user_mpm || 442 sdata->u.mesh.security & IEEE80211_MESH_SEC_AUTHED) 443 cfg80211_notify_new_peer_candidate(sdata->dev, addr, 444 elems->ie_start, 445 elems->total_len, 446 GFP_KERNEL); 447 else 448 sta = __mesh_sta_info_alloc(sdata, addr); 449 450 return sta; 451 } 452 453 /* 454 * mesh_sta_info_get - return mesh sta info entry for @addr. 455 * 456 * @sdata: local meshif 457 * @addr: peer's address 458 * @elems: IEs from beacon or mesh peering frame. 459 * 460 * Return existing or newly allocated sta_info under RCU read lock. 461 * (re)initialize with given IEs. 462 */ 463 static struct sta_info * 464 mesh_sta_info_get(struct ieee80211_sub_if_data *sdata, 465 u8 *addr, struct ieee802_11_elems *elems) __acquires(RCU) 466 { 467 struct sta_info *sta = NULL; 468 469 rcu_read_lock(); 470 sta = sta_info_get(sdata, addr); 471 if (sta) { 472 mesh_sta_info_init(sdata, sta, elems, false); 473 } else { 474 rcu_read_unlock(); 475 /* can't run atomic */ 476 sta = mesh_sta_info_alloc(sdata, addr, elems); 477 if (!sta) { 478 rcu_read_lock(); 479 return NULL; 480 } 481 482 mesh_sta_info_init(sdata, sta, elems, true); 483 484 if (sta_info_insert_rcu(sta)) 485 return NULL; 486 } 487 488 return sta; 489 } 490 491 /* 492 * mesh_neighbour_update - update or initialize new mesh neighbor. 493 * 494 * @sdata: local meshif 495 * @addr: peer's address 496 * @elems: IEs from beacon or mesh peering frame 497 * 498 * Initiates peering if appropriate. 499 */ 500 void mesh_neighbour_update(struct ieee80211_sub_if_data *sdata, 501 u8 *hw_addr, 502 struct ieee802_11_elems *elems) 503 { 504 struct sta_info *sta; 505 u32 changed = 0; 506 507 sta = mesh_sta_info_get(sdata, hw_addr, elems); 508 if (!sta) 509 goto out; 510 511 if (mesh_peer_accepts_plinks(elems) && 512 sta->plink_state == NL80211_PLINK_LISTEN && 513 sdata->u.mesh.accepting_plinks && 514 sdata->u.mesh.mshcfg.auto_open_plinks && 515 rssi_threshold_check(sta, sdata)) 516 changed = mesh_plink_open(sta); 517 518 ieee80211_mps_frame_release(sta, elems); 519 out: 520 rcu_read_unlock(); 521 ieee80211_mbss_info_change_notify(sdata, changed); 522 } 523 524 static void mesh_plink_timer(unsigned long data) 525 { 526 struct sta_info *sta; 527 __le16 llid, plid, reason; 528 struct ieee80211_sub_if_data *sdata; 529 struct mesh_config *mshcfg; 530 531 /* 532 * This STA is valid because sta_info_destroy() will 533 * del_timer_sync() this timer after having made sure 534 * it cannot be readded (by deleting the plink.) 535 */ 536 sta = (struct sta_info *) data; 537 538 if (sta->sdata->local->quiescing) 539 return; 540 541 spin_lock_bh(&sta->lock); 542 if (sta->ignore_plink_timer) { 543 sta->ignore_plink_timer = false; 544 spin_unlock_bh(&sta->lock); 545 return; 546 } 547 mpl_dbg(sta->sdata, 548 "Mesh plink timer for %pM fired on state %d\n", 549 sta->sta.addr, sta->plink_state); 550 reason = 0; 551 llid = sta->llid; 552 plid = sta->plid; 553 sdata = sta->sdata; 554 mshcfg = &sdata->u.mesh.mshcfg; 555 556 switch (sta->plink_state) { 557 case NL80211_PLINK_OPN_RCVD: 558 case NL80211_PLINK_OPN_SNT: 559 /* retry timer */ 560 if (sta->plink_retries < mshcfg->dot11MeshMaxRetries) { 561 u32 rand; 562 mpl_dbg(sta->sdata, 563 "Mesh plink for %pM (retry, timeout): %d %d\n", 564 sta->sta.addr, sta->plink_retries, 565 sta->plink_timeout); 566 get_random_bytes(&rand, sizeof(u32)); 567 sta->plink_timeout = sta->plink_timeout + 568 rand % sta->plink_timeout; 569 ++sta->plink_retries; 570 mod_plink_timer(sta, sta->plink_timeout); 571 spin_unlock_bh(&sta->lock); 572 mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_OPEN, 573 sta->sta.addr, llid, 0, 0); 574 break; 575 } 576 reason = cpu_to_le16(WLAN_REASON_MESH_MAX_RETRIES); 577 /* fall through on else */ 578 case NL80211_PLINK_CNF_RCVD: 579 /* confirm timer */ 580 if (!reason) 581 reason = cpu_to_le16(WLAN_REASON_MESH_CONFIRM_TIMEOUT); 582 sta->plink_state = NL80211_PLINK_HOLDING; 583 mod_plink_timer(sta, mshcfg->dot11MeshHoldingTimeout); 584 spin_unlock_bh(&sta->lock); 585 mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_CLOSE, 586 sta->sta.addr, llid, plid, reason); 587 break; 588 case NL80211_PLINK_HOLDING: 589 /* holding timer */ 590 del_timer(&sta->plink_timer); 591 mesh_plink_fsm_restart(sta); 592 spin_unlock_bh(&sta->lock); 593 break; 594 default: 595 spin_unlock_bh(&sta->lock); 596 break; 597 } 598 } 599 600 static inline void mesh_plink_timer_set(struct sta_info *sta, int timeout) 601 { 602 sta->plink_timer.expires = jiffies + (HZ * timeout / 1000); 603 sta->plink_timer.data = (unsigned long) sta; 604 sta->plink_timer.function = mesh_plink_timer; 605 sta->plink_timeout = timeout; 606 add_timer(&sta->plink_timer); 607 } 608 609 u32 mesh_plink_open(struct sta_info *sta) 610 { 611 __le16 llid; 612 struct ieee80211_sub_if_data *sdata = sta->sdata; 613 u32 changed; 614 615 if (!test_sta_flag(sta, WLAN_STA_AUTH)) 616 return 0; 617 618 spin_lock_bh(&sta->lock); 619 get_random_bytes(&llid, 2); 620 sta->llid = llid; 621 if (sta->plink_state != NL80211_PLINK_LISTEN && 622 sta->plink_state != NL80211_PLINK_BLOCKED) { 623 spin_unlock_bh(&sta->lock); 624 return 0; 625 } 626 sta->plink_state = NL80211_PLINK_OPN_SNT; 627 mesh_plink_timer_set(sta, sdata->u.mesh.mshcfg.dot11MeshRetryTimeout); 628 spin_unlock_bh(&sta->lock); 629 mpl_dbg(sdata, 630 "Mesh plink: starting establishment with %pM\n", 631 sta->sta.addr); 632 633 /* set the non-peer mode to active during peering */ 634 changed = ieee80211_mps_local_status_update(sdata); 635 636 mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_OPEN, 637 sta->sta.addr, llid, 0, 0); 638 return changed; 639 } 640 641 u32 mesh_plink_block(struct sta_info *sta) 642 { 643 u32 changed; 644 645 spin_lock_bh(&sta->lock); 646 changed = __mesh_plink_deactivate(sta); 647 sta->plink_state = NL80211_PLINK_BLOCKED; 648 spin_unlock_bh(&sta->lock); 649 650 return changed; 651 } 652 653 654 void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata, 655 struct ieee80211_mgmt *mgmt, size_t len, 656 struct ieee80211_rx_status *rx_status) 657 { 658 struct mesh_config *mshcfg = &sdata->u.mesh.mshcfg; 659 struct ieee802_11_elems elems; 660 struct sta_info *sta; 661 enum plink_event event; 662 enum ieee80211_self_protected_actioncode ftype; 663 size_t baselen; 664 bool matches_local = true; 665 u8 ie_len; 666 u8 *baseaddr; 667 u32 changed = 0; 668 __le16 plid, llid, reason; 669 670 /* need action_code, aux */ 671 if (len < IEEE80211_MIN_ACTION_SIZE + 3) 672 return; 673 674 if (sdata->u.mesh.user_mpm) 675 /* userspace must register for these */ 676 return; 677 678 if (is_multicast_ether_addr(mgmt->da)) { 679 mpl_dbg(sdata, 680 "Mesh plink: ignore frame from multicast address\n"); 681 return; 682 } 683 684 baseaddr = mgmt->u.action.u.self_prot.variable; 685 baselen = (u8 *) mgmt->u.action.u.self_prot.variable - (u8 *) mgmt; 686 if (mgmt->u.action.u.self_prot.action_code == 687 WLAN_SP_MESH_PEERING_CONFIRM) { 688 baseaddr += 4; 689 baselen += 4; 690 } 691 ieee802_11_parse_elems(baseaddr, len - baselen, &elems); 692 693 if (!elems.peering) { 694 mpl_dbg(sdata, 695 "Mesh plink: missing necessary peer link ie\n"); 696 return; 697 } 698 699 if (elems.rsn_len && 700 sdata->u.mesh.security == IEEE80211_MESH_SEC_NONE) { 701 mpl_dbg(sdata, 702 "Mesh plink: can't establish link with secure peer\n"); 703 return; 704 } 705 706 ftype = mgmt->u.action.u.self_prot.action_code; 707 ie_len = elems.peering_len; 708 if ((ftype == WLAN_SP_MESH_PEERING_OPEN && ie_len != 4) || 709 (ftype == WLAN_SP_MESH_PEERING_CONFIRM && ie_len != 6) || 710 (ftype == WLAN_SP_MESH_PEERING_CLOSE && ie_len != 6 711 && ie_len != 8)) { 712 mpl_dbg(sdata, 713 "Mesh plink: incorrect plink ie length %d %d\n", 714 ftype, ie_len); 715 return; 716 } 717 718 if (ftype != WLAN_SP_MESH_PEERING_CLOSE && 719 (!elems.mesh_id || !elems.mesh_config)) { 720 mpl_dbg(sdata, "Mesh plink: missing necessary ie\n"); 721 return; 722 } 723 /* Note the lines below are correct, the llid in the frame is the plid 724 * from the point of view of this host. 725 */ 726 memcpy(&plid, PLINK_GET_LLID(elems.peering), 2); 727 if (ftype == WLAN_SP_MESH_PEERING_CONFIRM || 728 (ftype == WLAN_SP_MESH_PEERING_CLOSE && ie_len == 8)) 729 memcpy(&llid, PLINK_GET_PLID(elems.peering), 2); 730 731 /* WARNING: Only for sta pointer, is dropped & re-acquired */ 732 rcu_read_lock(); 733 734 sta = sta_info_get(sdata, mgmt->sa); 735 if (!sta && ftype != WLAN_SP_MESH_PEERING_OPEN) { 736 mpl_dbg(sdata, "Mesh plink: cls or cnf from unknown peer\n"); 737 rcu_read_unlock(); 738 return; 739 } 740 741 if (ftype == WLAN_SP_MESH_PEERING_OPEN && 742 !rssi_threshold_check(sta, sdata)) { 743 mpl_dbg(sdata, "Mesh plink: %pM does not meet rssi threshold\n", 744 mgmt->sa); 745 rcu_read_unlock(); 746 return; 747 } 748 749 if (sta && !test_sta_flag(sta, WLAN_STA_AUTH)) { 750 mpl_dbg(sdata, "Mesh plink: Action frame from non-authed peer\n"); 751 rcu_read_unlock(); 752 return; 753 } 754 755 if (sta && sta->plink_state == NL80211_PLINK_BLOCKED) { 756 rcu_read_unlock(); 757 return; 758 } 759 760 /* Now we will figure out the appropriate event... */ 761 event = PLINK_UNDEFINED; 762 if (ftype != WLAN_SP_MESH_PEERING_CLOSE && 763 !mesh_matches_local(sdata, &elems)) { 764 matches_local = false; 765 switch (ftype) { 766 case WLAN_SP_MESH_PEERING_OPEN: 767 event = OPN_RJCT; 768 break; 769 case WLAN_SP_MESH_PEERING_CONFIRM: 770 event = CNF_RJCT; 771 break; 772 default: 773 break; 774 } 775 } 776 777 if (!sta && !matches_local) { 778 rcu_read_unlock(); 779 reason = cpu_to_le16(WLAN_REASON_MESH_CONFIG); 780 llid = 0; 781 mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_CLOSE, 782 mgmt->sa, llid, plid, reason); 783 return; 784 } else if (!sta) { 785 /* ftype == WLAN_SP_MESH_PEERING_OPEN */ 786 if (!mesh_plink_free_count(sdata)) { 787 mpl_dbg(sdata, "Mesh plink error: no more free plinks\n"); 788 rcu_read_unlock(); 789 return; 790 } 791 event = OPN_ACPT; 792 } else if (matches_local) { 793 switch (ftype) { 794 case WLAN_SP_MESH_PEERING_OPEN: 795 if (!mesh_plink_free_count(sdata) || 796 (sta->plid && sta->plid != plid)) 797 event = OPN_IGNR; 798 else 799 event = OPN_ACPT; 800 break; 801 case WLAN_SP_MESH_PEERING_CONFIRM: 802 if (!mesh_plink_free_count(sdata) || 803 (sta->llid != llid || sta->plid != plid)) 804 event = CNF_IGNR; 805 else 806 event = CNF_ACPT; 807 break; 808 case WLAN_SP_MESH_PEERING_CLOSE: 809 if (sta->plink_state == NL80211_PLINK_ESTAB) 810 /* Do not check for llid or plid. This does not 811 * follow the standard but since multiple plinks 812 * per sta are not supported, it is necessary in 813 * order to avoid a livelock when MP A sees an 814 * establish peer link to MP B but MP B does not 815 * see it. This can be caused by a timeout in 816 * B's peer link establishment or B beign 817 * restarted. 818 */ 819 event = CLS_ACPT; 820 else if (sta->plid != plid) 821 event = CLS_IGNR; 822 else if (ie_len == 7 && sta->llid != llid) 823 event = CLS_IGNR; 824 else 825 event = CLS_ACPT; 826 break; 827 default: 828 mpl_dbg(sdata, "Mesh plink: unknown frame subtype\n"); 829 rcu_read_unlock(); 830 return; 831 } 832 } 833 834 if (event == OPN_ACPT) { 835 rcu_read_unlock(); 836 /* allocate sta entry if necessary and update info */ 837 sta = mesh_sta_info_get(sdata, mgmt->sa, &elems); 838 if (!sta) { 839 mpl_dbg(sdata, "Mesh plink: failed to init peer!\n"); 840 rcu_read_unlock(); 841 return; 842 } 843 } 844 845 mpl_dbg(sdata, "peer %pM in state %s got event %s\n", mgmt->sa, 846 mplstates[sta->plink_state], mplevents[event]); 847 reason = 0; 848 spin_lock_bh(&sta->lock); 849 switch (sta->plink_state) { 850 /* spin_unlock as soon as state is updated at each case */ 851 case NL80211_PLINK_LISTEN: 852 switch (event) { 853 case CLS_ACPT: 854 mesh_plink_fsm_restart(sta); 855 spin_unlock_bh(&sta->lock); 856 break; 857 case OPN_ACPT: 858 sta->plink_state = NL80211_PLINK_OPN_RCVD; 859 sta->plid = plid; 860 get_random_bytes(&llid, 2); 861 sta->llid = llid; 862 mesh_plink_timer_set(sta, 863 mshcfg->dot11MeshRetryTimeout); 864 865 /* set the non-peer mode to active during peering */ 866 changed |= ieee80211_mps_local_status_update(sdata); 867 868 spin_unlock_bh(&sta->lock); 869 mesh_plink_frame_tx(sdata, 870 WLAN_SP_MESH_PEERING_OPEN, 871 sta->sta.addr, llid, 0, 0); 872 mesh_plink_frame_tx(sdata, 873 WLAN_SP_MESH_PEERING_CONFIRM, 874 sta->sta.addr, llid, plid, 0); 875 break; 876 default: 877 spin_unlock_bh(&sta->lock); 878 break; 879 } 880 break; 881 882 case NL80211_PLINK_OPN_SNT: 883 switch (event) { 884 case OPN_RJCT: 885 case CNF_RJCT: 886 reason = cpu_to_le16(WLAN_REASON_MESH_CONFIG); 887 case CLS_ACPT: 888 if (!reason) 889 reason = cpu_to_le16(WLAN_REASON_MESH_CLOSE); 890 sta->reason = reason; 891 sta->plink_state = NL80211_PLINK_HOLDING; 892 if (!mod_plink_timer(sta, 893 mshcfg->dot11MeshHoldingTimeout)) 894 sta->ignore_plink_timer = true; 895 896 llid = sta->llid; 897 spin_unlock_bh(&sta->lock); 898 mesh_plink_frame_tx(sdata, 899 WLAN_SP_MESH_PEERING_CLOSE, 900 sta->sta.addr, llid, plid, reason); 901 break; 902 case OPN_ACPT: 903 /* retry timer is left untouched */ 904 sta->plink_state = NL80211_PLINK_OPN_RCVD; 905 sta->plid = plid; 906 llid = sta->llid; 907 spin_unlock_bh(&sta->lock); 908 mesh_plink_frame_tx(sdata, 909 WLAN_SP_MESH_PEERING_CONFIRM, 910 sta->sta.addr, llid, plid, 0); 911 break; 912 case CNF_ACPT: 913 sta->plink_state = NL80211_PLINK_CNF_RCVD; 914 if (!mod_plink_timer(sta, 915 mshcfg->dot11MeshConfirmTimeout)) 916 sta->ignore_plink_timer = true; 917 918 spin_unlock_bh(&sta->lock); 919 break; 920 default: 921 spin_unlock_bh(&sta->lock); 922 break; 923 } 924 break; 925 926 case NL80211_PLINK_OPN_RCVD: 927 switch (event) { 928 case OPN_RJCT: 929 case CNF_RJCT: 930 reason = cpu_to_le16(WLAN_REASON_MESH_CONFIG); 931 case CLS_ACPT: 932 if (!reason) 933 reason = cpu_to_le16(WLAN_REASON_MESH_CLOSE); 934 sta->reason = reason; 935 sta->plink_state = NL80211_PLINK_HOLDING; 936 if (!mod_plink_timer(sta, 937 mshcfg->dot11MeshHoldingTimeout)) 938 sta->ignore_plink_timer = true; 939 940 llid = sta->llid; 941 spin_unlock_bh(&sta->lock); 942 mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_CLOSE, 943 sta->sta.addr, llid, plid, reason); 944 break; 945 case OPN_ACPT: 946 llid = sta->llid; 947 spin_unlock_bh(&sta->lock); 948 mesh_plink_frame_tx(sdata, 949 WLAN_SP_MESH_PEERING_CONFIRM, 950 sta->sta.addr, llid, plid, 0); 951 break; 952 case CNF_ACPT: 953 del_timer(&sta->plink_timer); 954 sta->plink_state = NL80211_PLINK_ESTAB; 955 spin_unlock_bh(&sta->lock); 956 changed |= mesh_plink_inc_estab_count(sdata); 957 changed |= mesh_set_ht_prot_mode(sdata); 958 changed |= mesh_set_short_slot_time(sdata); 959 mpl_dbg(sdata, "Mesh plink with %pM ESTABLISHED\n", 960 sta->sta.addr); 961 ieee80211_mps_sta_status_update(sta); 962 changed |= ieee80211_mps_set_sta_local_pm(sta, 963 mshcfg->power_mode); 964 break; 965 default: 966 spin_unlock_bh(&sta->lock); 967 break; 968 } 969 break; 970 971 case NL80211_PLINK_CNF_RCVD: 972 switch (event) { 973 case OPN_RJCT: 974 case CNF_RJCT: 975 reason = cpu_to_le16(WLAN_REASON_MESH_CONFIG); 976 case CLS_ACPT: 977 if (!reason) 978 reason = cpu_to_le16(WLAN_REASON_MESH_CLOSE); 979 sta->reason = reason; 980 sta->plink_state = NL80211_PLINK_HOLDING; 981 if (!mod_plink_timer(sta, 982 mshcfg->dot11MeshHoldingTimeout)) 983 sta->ignore_plink_timer = true; 984 985 llid = sta->llid; 986 spin_unlock_bh(&sta->lock); 987 mesh_plink_frame_tx(sdata, 988 WLAN_SP_MESH_PEERING_CLOSE, 989 sta->sta.addr, llid, plid, reason); 990 break; 991 case OPN_ACPT: 992 del_timer(&sta->plink_timer); 993 sta->plink_state = NL80211_PLINK_ESTAB; 994 spin_unlock_bh(&sta->lock); 995 changed |= mesh_plink_inc_estab_count(sdata); 996 changed |= mesh_set_ht_prot_mode(sdata); 997 changed |= mesh_set_short_slot_time(sdata); 998 mpl_dbg(sdata, "Mesh plink with %pM ESTABLISHED\n", 999 sta->sta.addr); 1000 mesh_plink_frame_tx(sdata, 1001 WLAN_SP_MESH_PEERING_CONFIRM, 1002 sta->sta.addr, llid, plid, 0); 1003 ieee80211_mps_sta_status_update(sta); 1004 changed |= ieee80211_mps_set_sta_local_pm(sta, 1005 mshcfg->power_mode); 1006 break; 1007 default: 1008 spin_unlock_bh(&sta->lock); 1009 break; 1010 } 1011 break; 1012 1013 case NL80211_PLINK_ESTAB: 1014 switch (event) { 1015 case CLS_ACPT: 1016 reason = cpu_to_le16(WLAN_REASON_MESH_CLOSE); 1017 sta->reason = reason; 1018 changed |= __mesh_plink_deactivate(sta); 1019 sta->plink_state = NL80211_PLINK_HOLDING; 1020 llid = sta->llid; 1021 mod_plink_timer(sta, mshcfg->dot11MeshHoldingTimeout); 1022 spin_unlock_bh(&sta->lock); 1023 changed |= mesh_set_ht_prot_mode(sdata); 1024 changed |= mesh_set_short_slot_time(sdata); 1025 mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_CLOSE, 1026 sta->sta.addr, llid, plid, reason); 1027 break; 1028 case OPN_ACPT: 1029 llid = sta->llid; 1030 spin_unlock_bh(&sta->lock); 1031 mesh_plink_frame_tx(sdata, 1032 WLAN_SP_MESH_PEERING_CONFIRM, 1033 sta->sta.addr, llid, plid, 0); 1034 break; 1035 default: 1036 spin_unlock_bh(&sta->lock); 1037 break; 1038 } 1039 break; 1040 case NL80211_PLINK_HOLDING: 1041 switch (event) { 1042 case CLS_ACPT: 1043 if (del_timer(&sta->plink_timer)) 1044 sta->ignore_plink_timer = 1; 1045 mesh_plink_fsm_restart(sta); 1046 spin_unlock_bh(&sta->lock); 1047 break; 1048 case OPN_ACPT: 1049 case CNF_ACPT: 1050 case OPN_RJCT: 1051 case CNF_RJCT: 1052 llid = sta->llid; 1053 reason = sta->reason; 1054 spin_unlock_bh(&sta->lock); 1055 mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_CLOSE, 1056 sta->sta.addr, llid, plid, reason); 1057 break; 1058 default: 1059 spin_unlock_bh(&sta->lock); 1060 } 1061 break; 1062 default: 1063 /* should not get here, PLINK_BLOCKED is dealt with at the 1064 * beginning of the function 1065 */ 1066 spin_unlock_bh(&sta->lock); 1067 break; 1068 } 1069 1070 rcu_read_unlock(); 1071 1072 if (changed) 1073 ieee80211_mbss_info_change_notify(sdata, changed); 1074 } 1075