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 10 #include <linux/slab.h> 11 #include <linux/etherdevice.h> 12 #include <asm/unaligned.h> 13 #include "wme.h" 14 #include "mesh.h" 15 16 #define TEST_FRAME_LEN 8192 17 #define MAX_METRIC 0xffffffff 18 #define ARITH_SHIFT 8 19 20 #define MAX_PREQ_QUEUE_LEN 64 21 22 /* Destination only */ 23 #define MP_F_DO 0x1 24 /* Reply and forward */ 25 #define MP_F_RF 0x2 26 /* Unknown Sequence Number */ 27 #define MP_F_USN 0x01 28 /* Reason code Present */ 29 #define MP_F_RCODE 0x02 30 31 static void mesh_queue_preq(struct mesh_path *, u8); 32 33 static inline u32 u32_field_get(const u8 *preq_elem, int offset, bool ae) 34 { 35 if (ae) 36 offset += 6; 37 return get_unaligned_le32(preq_elem + offset); 38 } 39 40 static inline u32 u16_field_get(const u8 *preq_elem, int offset, bool ae) 41 { 42 if (ae) 43 offset += 6; 44 return get_unaligned_le16(preq_elem + offset); 45 } 46 47 /* HWMP IE processing macros */ 48 #define AE_F (1<<6) 49 #define AE_F_SET(x) (*x & AE_F) 50 #define PREQ_IE_FLAGS(x) (*(x)) 51 #define PREQ_IE_HOPCOUNT(x) (*(x + 1)) 52 #define PREQ_IE_TTL(x) (*(x + 2)) 53 #define PREQ_IE_PREQ_ID(x) u32_field_get(x, 3, 0) 54 #define PREQ_IE_ORIG_ADDR(x) (x + 7) 55 #define PREQ_IE_ORIG_SN(x) u32_field_get(x, 13, 0) 56 #define PREQ_IE_LIFETIME(x) u32_field_get(x, 17, AE_F_SET(x)) 57 #define PREQ_IE_METRIC(x) u32_field_get(x, 21, AE_F_SET(x)) 58 #define PREQ_IE_TARGET_F(x) (*(AE_F_SET(x) ? x + 32 : x + 26)) 59 #define PREQ_IE_TARGET_ADDR(x) (AE_F_SET(x) ? x + 33 : x + 27) 60 #define PREQ_IE_TARGET_SN(x) u32_field_get(x, 33, AE_F_SET(x)) 61 62 63 #define PREP_IE_FLAGS(x) PREQ_IE_FLAGS(x) 64 #define PREP_IE_HOPCOUNT(x) PREQ_IE_HOPCOUNT(x) 65 #define PREP_IE_TTL(x) PREQ_IE_TTL(x) 66 #define PREP_IE_ORIG_ADDR(x) (AE_F_SET(x) ? x + 27 : x + 21) 67 #define PREP_IE_ORIG_SN(x) u32_field_get(x, 27, AE_F_SET(x)) 68 #define PREP_IE_LIFETIME(x) u32_field_get(x, 13, AE_F_SET(x)) 69 #define PREP_IE_METRIC(x) u32_field_get(x, 17, AE_F_SET(x)) 70 #define PREP_IE_TARGET_ADDR(x) (x + 3) 71 #define PREP_IE_TARGET_SN(x) u32_field_get(x, 9, 0) 72 73 #define PERR_IE_TTL(x) (*(x)) 74 #define PERR_IE_TARGET_FLAGS(x) (*(x + 2)) 75 #define PERR_IE_TARGET_ADDR(x) (x + 3) 76 #define PERR_IE_TARGET_SN(x) u32_field_get(x, 9, 0) 77 #define PERR_IE_TARGET_RCODE(x) u16_field_get(x, 13, 0) 78 79 #define MSEC_TO_TU(x) (x*1000/1024) 80 #define SN_GT(x, y) ((s32)(y - x) < 0) 81 #define SN_LT(x, y) ((s32)(x - y) < 0) 82 83 #define net_traversal_jiffies(s) \ 84 msecs_to_jiffies(s->u.mesh.mshcfg.dot11MeshHWMPnetDiameterTraversalTime) 85 #define default_lifetime(s) \ 86 MSEC_TO_TU(s->u.mesh.mshcfg.dot11MeshHWMPactivePathTimeout) 87 #define min_preq_int_jiff(s) \ 88 (msecs_to_jiffies(s->u.mesh.mshcfg.dot11MeshHWMPpreqMinInterval)) 89 #define max_preq_retries(s) (s->u.mesh.mshcfg.dot11MeshHWMPmaxPREQretries) 90 #define disc_timeout_jiff(s) \ 91 msecs_to_jiffies(sdata->u.mesh.mshcfg.min_discovery_timeout) 92 #define root_path_confirmation_jiffies(s) \ 93 msecs_to_jiffies(sdata->u.mesh.mshcfg.dot11MeshHWMPconfirmationInterval) 94 95 enum mpath_frame_type { 96 MPATH_PREQ = 0, 97 MPATH_PREP, 98 MPATH_PERR, 99 MPATH_RANN 100 }; 101 102 static const u8 broadcast_addr[ETH_ALEN] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff}; 103 104 static int mesh_path_sel_frame_tx(enum mpath_frame_type action, u8 flags, 105 const u8 *orig_addr, __le32 orig_sn, 106 u8 target_flags, const u8 *target, 107 __le32 target_sn, const u8 *da, 108 u8 hop_count, u8 ttl, 109 __le32 lifetime, __le32 metric, 110 __le32 preq_id, 111 struct ieee80211_sub_if_data *sdata) 112 { 113 struct ieee80211_local *local = sdata->local; 114 struct sk_buff *skb; 115 struct ieee80211_mgmt *mgmt; 116 u8 *pos, ie_len; 117 int hdr_len = offsetof(struct ieee80211_mgmt, u.action.u.mesh_action) + 118 sizeof(mgmt->u.action.u.mesh_action); 119 120 skb = dev_alloc_skb(local->tx_headroom + 121 hdr_len + 122 2 + 37); /* max HWMP IE */ 123 if (!skb) 124 return -1; 125 skb_reserve(skb, local->tx_headroom); 126 mgmt = (struct ieee80211_mgmt *) skb_put(skb, hdr_len); 127 memset(mgmt, 0, hdr_len); 128 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 129 IEEE80211_STYPE_ACTION); 130 131 memcpy(mgmt->da, da, ETH_ALEN); 132 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN); 133 /* BSSID == SA */ 134 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN); 135 mgmt->u.action.category = WLAN_CATEGORY_MESH_ACTION; 136 mgmt->u.action.u.mesh_action.action_code = 137 WLAN_MESH_ACTION_HWMP_PATH_SELECTION; 138 139 switch (action) { 140 case MPATH_PREQ: 141 mhwmp_dbg(sdata, "sending PREQ to %pM\n", target); 142 ie_len = 37; 143 pos = skb_put(skb, 2 + ie_len); 144 *pos++ = WLAN_EID_PREQ; 145 break; 146 case MPATH_PREP: 147 mhwmp_dbg(sdata, "sending PREP to %pM\n", orig_addr); 148 ie_len = 31; 149 pos = skb_put(skb, 2 + ie_len); 150 *pos++ = WLAN_EID_PREP; 151 break; 152 case MPATH_RANN: 153 mhwmp_dbg(sdata, "sending RANN from %pM\n", orig_addr); 154 ie_len = sizeof(struct ieee80211_rann_ie); 155 pos = skb_put(skb, 2 + ie_len); 156 *pos++ = WLAN_EID_RANN; 157 break; 158 default: 159 kfree_skb(skb); 160 return -ENOTSUPP; 161 break; 162 } 163 *pos++ = ie_len; 164 *pos++ = flags; 165 *pos++ = hop_count; 166 *pos++ = ttl; 167 if (action == MPATH_PREP) { 168 memcpy(pos, target, ETH_ALEN); 169 pos += ETH_ALEN; 170 memcpy(pos, &target_sn, 4); 171 pos += 4; 172 } else { 173 if (action == MPATH_PREQ) { 174 memcpy(pos, &preq_id, 4); 175 pos += 4; 176 } 177 memcpy(pos, orig_addr, ETH_ALEN); 178 pos += ETH_ALEN; 179 memcpy(pos, &orig_sn, 4); 180 pos += 4; 181 } 182 memcpy(pos, &lifetime, 4); /* interval for RANN */ 183 pos += 4; 184 memcpy(pos, &metric, 4); 185 pos += 4; 186 if (action == MPATH_PREQ) { 187 *pos++ = 1; /* destination count */ 188 *pos++ = target_flags; 189 memcpy(pos, target, ETH_ALEN); 190 pos += ETH_ALEN; 191 memcpy(pos, &target_sn, 4); 192 pos += 4; 193 } else if (action == MPATH_PREP) { 194 memcpy(pos, orig_addr, ETH_ALEN); 195 pos += ETH_ALEN; 196 memcpy(pos, &orig_sn, 4); 197 pos += 4; 198 } 199 200 ieee80211_tx_skb(sdata, skb); 201 return 0; 202 } 203 204 205 /* Headroom is not adjusted. Caller should ensure that skb has sufficient 206 * headroom in case the frame is encrypted. */ 207 static void prepare_frame_for_deferred_tx(struct ieee80211_sub_if_data *sdata, 208 struct sk_buff *skb) 209 { 210 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 211 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 212 213 skb_set_mac_header(skb, 0); 214 skb_set_network_header(skb, 0); 215 skb_set_transport_header(skb, 0); 216 217 /* Send all internal mgmt frames on VO. Accordingly set TID to 7. */ 218 skb_set_queue_mapping(skb, IEEE80211_AC_VO); 219 skb->priority = 7; 220 221 info->control.vif = &sdata->vif; 222 info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING; 223 ieee80211_set_qos_hdr(sdata, skb); 224 ieee80211_mps_set_frame_flags(sdata, NULL, hdr); 225 } 226 227 /** 228 * mesh_path_error_tx - Sends a PERR mesh management frame 229 * 230 * @ttl: allowed remaining hops 231 * @target: broken destination 232 * @target_sn: SN of the broken destination 233 * @target_rcode: reason code for this PERR 234 * @ra: node this frame is addressed to 235 * @sdata: local mesh subif 236 * 237 * Note: This function may be called with driver locks taken that the driver 238 * also acquires in the TX path. To avoid a deadlock we don't transmit the 239 * frame directly but add it to the pending queue instead. 240 */ 241 int mesh_path_error_tx(struct ieee80211_sub_if_data *sdata, 242 u8 ttl, const u8 *target, __le32 target_sn, 243 __le16 target_rcode, const u8 *ra) 244 { 245 struct ieee80211_local *local = sdata->local; 246 struct sk_buff *skb; 247 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 248 struct ieee80211_mgmt *mgmt; 249 u8 *pos, ie_len; 250 int hdr_len = offsetof(struct ieee80211_mgmt, u.action.u.mesh_action) + 251 sizeof(mgmt->u.action.u.mesh_action); 252 253 if (time_before(jiffies, ifmsh->next_perr)) 254 return -EAGAIN; 255 256 skb = dev_alloc_skb(local->tx_headroom + 257 IEEE80211_ENCRYPT_HEADROOM + 258 IEEE80211_ENCRYPT_TAILROOM + 259 hdr_len + 260 2 + 15 /* PERR IE */); 261 if (!skb) 262 return -1; 263 skb_reserve(skb, local->tx_headroom + IEEE80211_ENCRYPT_HEADROOM); 264 mgmt = (struct ieee80211_mgmt *) skb_put(skb, hdr_len); 265 memset(mgmt, 0, hdr_len); 266 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 267 IEEE80211_STYPE_ACTION); 268 269 memcpy(mgmt->da, ra, ETH_ALEN); 270 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN); 271 /* BSSID == SA */ 272 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN); 273 mgmt->u.action.category = WLAN_CATEGORY_MESH_ACTION; 274 mgmt->u.action.u.mesh_action.action_code = 275 WLAN_MESH_ACTION_HWMP_PATH_SELECTION; 276 ie_len = 15; 277 pos = skb_put(skb, 2 + ie_len); 278 *pos++ = WLAN_EID_PERR; 279 *pos++ = ie_len; 280 /* ttl */ 281 *pos++ = ttl; 282 /* number of destinations */ 283 *pos++ = 1; 284 /* 285 * flags bit, bit 1 is unset if we know the sequence number and 286 * bit 2 is set if we have a reason code 287 */ 288 *pos = 0; 289 if (!target_sn) 290 *pos |= MP_F_USN; 291 if (target_rcode) 292 *pos |= MP_F_RCODE; 293 pos++; 294 memcpy(pos, target, ETH_ALEN); 295 pos += ETH_ALEN; 296 memcpy(pos, &target_sn, 4); 297 pos += 4; 298 memcpy(pos, &target_rcode, 2); 299 300 /* see note in function header */ 301 prepare_frame_for_deferred_tx(sdata, skb); 302 ifmsh->next_perr = TU_TO_EXP_TIME( 303 ifmsh->mshcfg.dot11MeshHWMPperrMinInterval); 304 ieee80211_add_pending_skb(local, skb); 305 return 0; 306 } 307 308 void ieee80211s_update_metric(struct ieee80211_local *local, 309 struct sta_info *sta, struct sk_buff *skb) 310 { 311 struct ieee80211_tx_info *txinfo = IEEE80211_SKB_CB(skb); 312 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 313 int failed; 314 315 if (!ieee80211_is_data(hdr->frame_control)) 316 return; 317 318 failed = !(txinfo->flags & IEEE80211_TX_STAT_ACK); 319 320 /* moving average, scaled to 100 */ 321 sta->fail_avg = ((80 * sta->fail_avg + 5) / 100 + 20 * failed); 322 if (sta->fail_avg > 95) 323 mesh_plink_broken(sta); 324 } 325 326 static u32 airtime_link_metric_get(struct ieee80211_local *local, 327 struct sta_info *sta) 328 { 329 struct rate_info rinfo; 330 /* This should be adjusted for each device */ 331 int device_constant = 1 << ARITH_SHIFT; 332 int test_frame_len = TEST_FRAME_LEN << ARITH_SHIFT; 333 int s_unit = 1 << ARITH_SHIFT; 334 int rate, err; 335 u32 tx_time, estimated_retx; 336 u64 result; 337 338 if (sta->fail_avg >= 100) 339 return MAX_METRIC; 340 341 sta_set_rate_info_tx(sta, &sta->last_tx_rate, &rinfo); 342 rate = cfg80211_calculate_bitrate(&rinfo); 343 if (WARN_ON(!rate)) 344 return MAX_METRIC; 345 346 err = (sta->fail_avg << ARITH_SHIFT) / 100; 347 348 /* bitrate is in units of 100 Kbps, while we need rate in units of 349 * 1Mbps. This will be corrected on tx_time computation. 350 */ 351 tx_time = (device_constant + 10 * test_frame_len / rate); 352 estimated_retx = ((1 << (2 * ARITH_SHIFT)) / (s_unit - err)); 353 result = (tx_time * estimated_retx) >> (2 * ARITH_SHIFT) ; 354 return (u32)result; 355 } 356 357 /** 358 * hwmp_route_info_get - Update routing info to originator and transmitter 359 * 360 * @sdata: local mesh subif 361 * @mgmt: mesh management frame 362 * @hwmp_ie: hwmp information element (PREP or PREQ) 363 * @action: type of hwmp ie 364 * 365 * This function updates the path routing information to the originator and the 366 * transmitter of a HWMP PREQ or PREP frame. 367 * 368 * Returns: metric to frame originator or 0 if the frame should not be further 369 * processed 370 * 371 * Notes: this function is the only place (besides user-provided info) where 372 * path routing information is updated. 373 */ 374 static u32 hwmp_route_info_get(struct ieee80211_sub_if_data *sdata, 375 struct ieee80211_mgmt *mgmt, 376 const u8 *hwmp_ie, enum mpath_frame_type action) 377 { 378 struct ieee80211_local *local = sdata->local; 379 struct mesh_path *mpath; 380 struct sta_info *sta; 381 bool fresh_info; 382 const u8 *orig_addr, *ta; 383 u32 orig_sn, orig_metric; 384 unsigned long orig_lifetime, exp_time; 385 u32 last_hop_metric, new_metric; 386 bool process = true; 387 388 rcu_read_lock(); 389 sta = sta_info_get(sdata, mgmt->sa); 390 if (!sta) { 391 rcu_read_unlock(); 392 return 0; 393 } 394 395 last_hop_metric = airtime_link_metric_get(local, sta); 396 /* Update and check originator routing info */ 397 fresh_info = true; 398 399 switch (action) { 400 case MPATH_PREQ: 401 orig_addr = PREQ_IE_ORIG_ADDR(hwmp_ie); 402 orig_sn = PREQ_IE_ORIG_SN(hwmp_ie); 403 orig_lifetime = PREQ_IE_LIFETIME(hwmp_ie); 404 orig_metric = PREQ_IE_METRIC(hwmp_ie); 405 break; 406 case MPATH_PREP: 407 /* Originator here refers to the MP that was the target in the 408 * Path Request. We divert from the nomenclature in the draft 409 * so that we can easily use a single function to gather path 410 * information from both PREQ and PREP frames. 411 */ 412 orig_addr = PREP_IE_TARGET_ADDR(hwmp_ie); 413 orig_sn = PREP_IE_TARGET_SN(hwmp_ie); 414 orig_lifetime = PREP_IE_LIFETIME(hwmp_ie); 415 orig_metric = PREP_IE_METRIC(hwmp_ie); 416 break; 417 default: 418 rcu_read_unlock(); 419 return 0; 420 } 421 new_metric = orig_metric + last_hop_metric; 422 if (new_metric < orig_metric) 423 new_metric = MAX_METRIC; 424 exp_time = TU_TO_EXP_TIME(orig_lifetime); 425 426 if (ether_addr_equal(orig_addr, sdata->vif.addr)) { 427 /* This MP is the originator, we are not interested in this 428 * frame, except for updating transmitter's path info. 429 */ 430 process = false; 431 fresh_info = false; 432 } else { 433 mpath = mesh_path_lookup(sdata, orig_addr); 434 if (mpath) { 435 spin_lock_bh(&mpath->state_lock); 436 if (mpath->flags & MESH_PATH_FIXED) 437 fresh_info = false; 438 else if ((mpath->flags & MESH_PATH_ACTIVE) && 439 (mpath->flags & MESH_PATH_SN_VALID)) { 440 if (SN_GT(mpath->sn, orig_sn) || 441 (mpath->sn == orig_sn && 442 new_metric >= mpath->metric)) { 443 process = false; 444 fresh_info = false; 445 } 446 } 447 } else { 448 mpath = mesh_path_add(sdata, orig_addr); 449 if (IS_ERR(mpath)) { 450 rcu_read_unlock(); 451 return 0; 452 } 453 spin_lock_bh(&mpath->state_lock); 454 } 455 456 if (fresh_info) { 457 mesh_path_assign_nexthop(mpath, sta); 458 mpath->flags |= MESH_PATH_SN_VALID; 459 mpath->metric = new_metric; 460 mpath->sn = orig_sn; 461 mpath->exp_time = time_after(mpath->exp_time, exp_time) 462 ? mpath->exp_time : exp_time; 463 mesh_path_activate(mpath); 464 spin_unlock_bh(&mpath->state_lock); 465 mesh_path_tx_pending(mpath); 466 /* draft says preq_id should be saved to, but there does 467 * not seem to be any use for it, skipping by now 468 */ 469 } else 470 spin_unlock_bh(&mpath->state_lock); 471 } 472 473 /* Update and check transmitter routing info */ 474 ta = mgmt->sa; 475 if (ether_addr_equal(orig_addr, ta)) 476 fresh_info = false; 477 else { 478 fresh_info = true; 479 480 mpath = mesh_path_lookup(sdata, ta); 481 if (mpath) { 482 spin_lock_bh(&mpath->state_lock); 483 if ((mpath->flags & MESH_PATH_FIXED) || 484 ((mpath->flags & MESH_PATH_ACTIVE) && 485 (last_hop_metric > mpath->metric))) 486 fresh_info = false; 487 } else { 488 mpath = mesh_path_add(sdata, ta); 489 if (IS_ERR(mpath)) { 490 rcu_read_unlock(); 491 return 0; 492 } 493 spin_lock_bh(&mpath->state_lock); 494 } 495 496 if (fresh_info) { 497 mesh_path_assign_nexthop(mpath, sta); 498 mpath->metric = last_hop_metric; 499 mpath->exp_time = time_after(mpath->exp_time, exp_time) 500 ? mpath->exp_time : exp_time; 501 mesh_path_activate(mpath); 502 spin_unlock_bh(&mpath->state_lock); 503 mesh_path_tx_pending(mpath); 504 } else 505 spin_unlock_bh(&mpath->state_lock); 506 } 507 508 rcu_read_unlock(); 509 510 return process ? new_metric : 0; 511 } 512 513 static void hwmp_preq_frame_process(struct ieee80211_sub_if_data *sdata, 514 struct ieee80211_mgmt *mgmt, 515 const u8 *preq_elem, u32 metric) 516 { 517 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 518 struct mesh_path *mpath = NULL; 519 const u8 *target_addr, *orig_addr; 520 const u8 *da; 521 u8 target_flags, ttl, flags; 522 u32 orig_sn, target_sn, lifetime, orig_metric; 523 bool reply = false; 524 bool forward = true; 525 bool root_is_gate; 526 527 /* Update target SN, if present */ 528 target_addr = PREQ_IE_TARGET_ADDR(preq_elem); 529 orig_addr = PREQ_IE_ORIG_ADDR(preq_elem); 530 target_sn = PREQ_IE_TARGET_SN(preq_elem); 531 orig_sn = PREQ_IE_ORIG_SN(preq_elem); 532 target_flags = PREQ_IE_TARGET_F(preq_elem); 533 orig_metric = metric; 534 /* Proactive PREQ gate announcements */ 535 flags = PREQ_IE_FLAGS(preq_elem); 536 root_is_gate = !!(flags & RANN_FLAG_IS_GATE); 537 538 mhwmp_dbg(sdata, "received PREQ from %pM\n", orig_addr); 539 540 if (ether_addr_equal(target_addr, sdata->vif.addr)) { 541 mhwmp_dbg(sdata, "PREQ is for us\n"); 542 forward = false; 543 reply = true; 544 metric = 0; 545 if (time_after(jiffies, ifmsh->last_sn_update + 546 net_traversal_jiffies(sdata)) || 547 time_before(jiffies, ifmsh->last_sn_update)) { 548 target_sn = ++ifmsh->sn; 549 ifmsh->last_sn_update = jiffies; 550 } 551 } else if (is_broadcast_ether_addr(target_addr) && 552 (target_flags & IEEE80211_PREQ_TO_FLAG)) { 553 rcu_read_lock(); 554 mpath = mesh_path_lookup(sdata, orig_addr); 555 if (mpath) { 556 if (flags & IEEE80211_PREQ_PROACTIVE_PREP_FLAG) { 557 reply = true; 558 target_addr = sdata->vif.addr; 559 target_sn = ++ifmsh->sn; 560 metric = 0; 561 ifmsh->last_sn_update = jiffies; 562 } 563 if (root_is_gate) 564 mesh_path_add_gate(mpath); 565 } 566 rcu_read_unlock(); 567 } else { 568 rcu_read_lock(); 569 mpath = mesh_path_lookup(sdata, target_addr); 570 if (mpath) { 571 if ((!(mpath->flags & MESH_PATH_SN_VALID)) || 572 SN_LT(mpath->sn, target_sn)) { 573 mpath->sn = target_sn; 574 mpath->flags |= MESH_PATH_SN_VALID; 575 } else if ((!(target_flags & MP_F_DO)) && 576 (mpath->flags & MESH_PATH_ACTIVE)) { 577 reply = true; 578 metric = mpath->metric; 579 target_sn = mpath->sn; 580 if (target_flags & MP_F_RF) 581 target_flags |= MP_F_DO; 582 else 583 forward = false; 584 } 585 } 586 rcu_read_unlock(); 587 } 588 589 if (reply) { 590 lifetime = PREQ_IE_LIFETIME(preq_elem); 591 ttl = ifmsh->mshcfg.element_ttl; 592 if (ttl != 0) { 593 mhwmp_dbg(sdata, "replying to the PREQ\n"); 594 mesh_path_sel_frame_tx(MPATH_PREP, 0, orig_addr, 595 cpu_to_le32(orig_sn), 0, target_addr, 596 cpu_to_le32(target_sn), mgmt->sa, 0, ttl, 597 cpu_to_le32(lifetime), cpu_to_le32(metric), 598 0, sdata); 599 } else { 600 ifmsh->mshstats.dropped_frames_ttl++; 601 } 602 } 603 604 if (forward && ifmsh->mshcfg.dot11MeshForwarding) { 605 u32 preq_id; 606 u8 hopcount; 607 608 ttl = PREQ_IE_TTL(preq_elem); 609 lifetime = PREQ_IE_LIFETIME(preq_elem); 610 if (ttl <= 1) { 611 ifmsh->mshstats.dropped_frames_ttl++; 612 return; 613 } 614 mhwmp_dbg(sdata, "forwarding the PREQ from %pM\n", orig_addr); 615 --ttl; 616 preq_id = PREQ_IE_PREQ_ID(preq_elem); 617 hopcount = PREQ_IE_HOPCOUNT(preq_elem) + 1; 618 da = (mpath && mpath->is_root) ? 619 mpath->rann_snd_addr : broadcast_addr; 620 621 if (flags & IEEE80211_PREQ_PROACTIVE_PREP_FLAG) { 622 target_addr = PREQ_IE_TARGET_ADDR(preq_elem); 623 target_sn = PREQ_IE_TARGET_SN(preq_elem); 624 metric = orig_metric; 625 } 626 627 mesh_path_sel_frame_tx(MPATH_PREQ, flags, orig_addr, 628 cpu_to_le32(orig_sn), target_flags, target_addr, 629 cpu_to_le32(target_sn), da, 630 hopcount, ttl, cpu_to_le32(lifetime), 631 cpu_to_le32(metric), cpu_to_le32(preq_id), 632 sdata); 633 if (!is_multicast_ether_addr(da)) 634 ifmsh->mshstats.fwded_unicast++; 635 else 636 ifmsh->mshstats.fwded_mcast++; 637 ifmsh->mshstats.fwded_frames++; 638 } 639 } 640 641 642 static inline struct sta_info * 643 next_hop_deref_protected(struct mesh_path *mpath) 644 { 645 return rcu_dereference_protected(mpath->next_hop, 646 lockdep_is_held(&mpath->state_lock)); 647 } 648 649 650 static void hwmp_prep_frame_process(struct ieee80211_sub_if_data *sdata, 651 struct ieee80211_mgmt *mgmt, 652 const u8 *prep_elem, u32 metric) 653 { 654 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 655 struct mesh_path *mpath; 656 const u8 *target_addr, *orig_addr; 657 u8 ttl, hopcount, flags; 658 u8 next_hop[ETH_ALEN]; 659 u32 target_sn, orig_sn, lifetime; 660 661 mhwmp_dbg(sdata, "received PREP from %pM\n", 662 PREP_IE_TARGET_ADDR(prep_elem)); 663 664 orig_addr = PREP_IE_ORIG_ADDR(prep_elem); 665 if (ether_addr_equal(orig_addr, sdata->vif.addr)) 666 /* destination, no forwarding required */ 667 return; 668 669 if (!ifmsh->mshcfg.dot11MeshForwarding) 670 return; 671 672 ttl = PREP_IE_TTL(prep_elem); 673 if (ttl <= 1) { 674 sdata->u.mesh.mshstats.dropped_frames_ttl++; 675 return; 676 } 677 678 rcu_read_lock(); 679 mpath = mesh_path_lookup(sdata, orig_addr); 680 if (mpath) 681 spin_lock_bh(&mpath->state_lock); 682 else 683 goto fail; 684 if (!(mpath->flags & MESH_PATH_ACTIVE)) { 685 spin_unlock_bh(&mpath->state_lock); 686 goto fail; 687 } 688 memcpy(next_hop, next_hop_deref_protected(mpath)->sta.addr, ETH_ALEN); 689 spin_unlock_bh(&mpath->state_lock); 690 --ttl; 691 flags = PREP_IE_FLAGS(prep_elem); 692 lifetime = PREP_IE_LIFETIME(prep_elem); 693 hopcount = PREP_IE_HOPCOUNT(prep_elem) + 1; 694 target_addr = PREP_IE_TARGET_ADDR(prep_elem); 695 target_sn = PREP_IE_TARGET_SN(prep_elem); 696 orig_sn = PREP_IE_ORIG_SN(prep_elem); 697 698 mesh_path_sel_frame_tx(MPATH_PREP, flags, orig_addr, 699 cpu_to_le32(orig_sn), 0, target_addr, 700 cpu_to_le32(target_sn), next_hop, hopcount, 701 ttl, cpu_to_le32(lifetime), cpu_to_le32(metric), 702 0, sdata); 703 rcu_read_unlock(); 704 705 sdata->u.mesh.mshstats.fwded_unicast++; 706 sdata->u.mesh.mshstats.fwded_frames++; 707 return; 708 709 fail: 710 rcu_read_unlock(); 711 sdata->u.mesh.mshstats.dropped_frames_no_route++; 712 } 713 714 static void hwmp_perr_frame_process(struct ieee80211_sub_if_data *sdata, 715 struct ieee80211_mgmt *mgmt, 716 const u8 *perr_elem) 717 { 718 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 719 struct mesh_path *mpath; 720 u8 ttl; 721 const u8 *ta, *target_addr; 722 u32 target_sn; 723 u16 target_rcode; 724 725 ta = mgmt->sa; 726 ttl = PERR_IE_TTL(perr_elem); 727 if (ttl <= 1) { 728 ifmsh->mshstats.dropped_frames_ttl++; 729 return; 730 } 731 ttl--; 732 target_addr = PERR_IE_TARGET_ADDR(perr_elem); 733 target_sn = PERR_IE_TARGET_SN(perr_elem); 734 target_rcode = PERR_IE_TARGET_RCODE(perr_elem); 735 736 rcu_read_lock(); 737 mpath = mesh_path_lookup(sdata, target_addr); 738 if (mpath) { 739 struct sta_info *sta; 740 741 spin_lock_bh(&mpath->state_lock); 742 sta = next_hop_deref_protected(mpath); 743 if (mpath->flags & MESH_PATH_ACTIVE && 744 ether_addr_equal(ta, sta->sta.addr) && 745 (!(mpath->flags & MESH_PATH_SN_VALID) || 746 SN_GT(target_sn, mpath->sn))) { 747 mpath->flags &= ~MESH_PATH_ACTIVE; 748 mpath->sn = target_sn; 749 spin_unlock_bh(&mpath->state_lock); 750 if (!ifmsh->mshcfg.dot11MeshForwarding) 751 goto endperr; 752 mesh_path_error_tx(sdata, ttl, target_addr, 753 cpu_to_le32(target_sn), 754 cpu_to_le16(target_rcode), 755 broadcast_addr); 756 } else 757 spin_unlock_bh(&mpath->state_lock); 758 } 759 endperr: 760 rcu_read_unlock(); 761 } 762 763 static void hwmp_rann_frame_process(struct ieee80211_sub_if_data *sdata, 764 struct ieee80211_mgmt *mgmt, 765 const struct ieee80211_rann_ie *rann) 766 { 767 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 768 struct ieee80211_local *local = sdata->local; 769 struct sta_info *sta; 770 struct mesh_path *mpath; 771 u8 ttl, flags, hopcount; 772 const u8 *orig_addr; 773 u32 orig_sn, metric, metric_txsta, interval; 774 bool root_is_gate; 775 776 ttl = rann->rann_ttl; 777 flags = rann->rann_flags; 778 root_is_gate = !!(flags & RANN_FLAG_IS_GATE); 779 orig_addr = rann->rann_addr; 780 orig_sn = le32_to_cpu(rann->rann_seq); 781 interval = le32_to_cpu(rann->rann_interval); 782 hopcount = rann->rann_hopcount; 783 hopcount++; 784 metric = le32_to_cpu(rann->rann_metric); 785 786 /* Ignore our own RANNs */ 787 if (ether_addr_equal(orig_addr, sdata->vif.addr)) 788 return; 789 790 mhwmp_dbg(sdata, 791 "received RANN from %pM via neighbour %pM (is_gate=%d)\n", 792 orig_addr, mgmt->sa, root_is_gate); 793 794 rcu_read_lock(); 795 sta = sta_info_get(sdata, mgmt->sa); 796 if (!sta) { 797 rcu_read_unlock(); 798 return; 799 } 800 801 metric_txsta = airtime_link_metric_get(local, sta); 802 803 mpath = mesh_path_lookup(sdata, orig_addr); 804 if (!mpath) { 805 mpath = mesh_path_add(sdata, orig_addr); 806 if (IS_ERR(mpath)) { 807 rcu_read_unlock(); 808 sdata->u.mesh.mshstats.dropped_frames_no_route++; 809 return; 810 } 811 } 812 813 if (!(SN_LT(mpath->sn, orig_sn)) && 814 !(mpath->sn == orig_sn && metric < mpath->rann_metric)) { 815 rcu_read_unlock(); 816 return; 817 } 818 819 if ((!(mpath->flags & (MESH_PATH_ACTIVE | MESH_PATH_RESOLVING)) || 820 (time_after(jiffies, mpath->last_preq_to_root + 821 root_path_confirmation_jiffies(sdata)) || 822 time_before(jiffies, mpath->last_preq_to_root))) && 823 !(mpath->flags & MESH_PATH_FIXED) && (ttl != 0)) { 824 mhwmp_dbg(sdata, 825 "time to refresh root mpath %pM\n", 826 orig_addr); 827 mesh_queue_preq(mpath, PREQ_Q_F_START | PREQ_Q_F_REFRESH); 828 mpath->last_preq_to_root = jiffies; 829 } 830 831 mpath->sn = orig_sn; 832 mpath->rann_metric = metric + metric_txsta; 833 mpath->is_root = true; 834 /* Recording RANNs sender address to send individually 835 * addressed PREQs destined for root mesh STA */ 836 memcpy(mpath->rann_snd_addr, mgmt->sa, ETH_ALEN); 837 838 if (root_is_gate) 839 mesh_path_add_gate(mpath); 840 841 if (ttl <= 1) { 842 ifmsh->mshstats.dropped_frames_ttl++; 843 rcu_read_unlock(); 844 return; 845 } 846 ttl--; 847 848 if (ifmsh->mshcfg.dot11MeshForwarding) { 849 mesh_path_sel_frame_tx(MPATH_RANN, flags, orig_addr, 850 cpu_to_le32(orig_sn), 851 0, NULL, 0, broadcast_addr, 852 hopcount, ttl, cpu_to_le32(interval), 853 cpu_to_le32(metric + metric_txsta), 854 0, sdata); 855 } 856 857 rcu_read_unlock(); 858 } 859 860 861 void mesh_rx_path_sel_frame(struct ieee80211_sub_if_data *sdata, 862 struct ieee80211_mgmt *mgmt, size_t len) 863 { 864 struct ieee802_11_elems elems; 865 size_t baselen; 866 u32 last_hop_metric; 867 struct sta_info *sta; 868 869 /* need action_code */ 870 if (len < IEEE80211_MIN_ACTION_SIZE + 1) 871 return; 872 873 rcu_read_lock(); 874 sta = sta_info_get(sdata, mgmt->sa); 875 if (!sta || sta->plink_state != NL80211_PLINK_ESTAB) { 876 rcu_read_unlock(); 877 return; 878 } 879 rcu_read_unlock(); 880 881 baselen = (u8 *) mgmt->u.action.u.mesh_action.variable - (u8 *) mgmt; 882 ieee802_11_parse_elems(mgmt->u.action.u.mesh_action.variable, 883 len - baselen, false, &elems); 884 885 if (elems.preq) { 886 if (elems.preq_len != 37) 887 /* Right now we support just 1 destination and no AE */ 888 return; 889 last_hop_metric = hwmp_route_info_get(sdata, mgmt, elems.preq, 890 MPATH_PREQ); 891 if (last_hop_metric) 892 hwmp_preq_frame_process(sdata, mgmt, elems.preq, 893 last_hop_metric); 894 } 895 if (elems.prep) { 896 if (elems.prep_len != 31) 897 /* Right now we support no AE */ 898 return; 899 last_hop_metric = hwmp_route_info_get(sdata, mgmt, elems.prep, 900 MPATH_PREP); 901 if (last_hop_metric) 902 hwmp_prep_frame_process(sdata, mgmt, elems.prep, 903 last_hop_metric); 904 } 905 if (elems.perr) { 906 if (elems.perr_len != 15) 907 /* Right now we support only one destination per PERR */ 908 return; 909 hwmp_perr_frame_process(sdata, mgmt, elems.perr); 910 } 911 if (elems.rann) 912 hwmp_rann_frame_process(sdata, mgmt, elems.rann); 913 } 914 915 /** 916 * mesh_queue_preq - queue a PREQ to a given destination 917 * 918 * @mpath: mesh path to discover 919 * @flags: special attributes of the PREQ to be sent 920 * 921 * Locking: the function must be called from within a rcu read lock block. 922 * 923 */ 924 static void mesh_queue_preq(struct mesh_path *mpath, u8 flags) 925 { 926 struct ieee80211_sub_if_data *sdata = mpath->sdata; 927 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 928 struct mesh_preq_queue *preq_node; 929 930 preq_node = kmalloc(sizeof(struct mesh_preq_queue), GFP_ATOMIC); 931 if (!preq_node) { 932 mhwmp_dbg(sdata, "could not allocate PREQ node\n"); 933 return; 934 } 935 936 spin_lock_bh(&ifmsh->mesh_preq_queue_lock); 937 if (ifmsh->preq_queue_len == MAX_PREQ_QUEUE_LEN) { 938 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock); 939 kfree(preq_node); 940 if (printk_ratelimit()) 941 mhwmp_dbg(sdata, "PREQ node queue full\n"); 942 return; 943 } 944 945 spin_lock(&mpath->state_lock); 946 if (mpath->flags & MESH_PATH_REQ_QUEUED) { 947 spin_unlock(&mpath->state_lock); 948 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock); 949 kfree(preq_node); 950 return; 951 } 952 953 memcpy(preq_node->dst, mpath->dst, ETH_ALEN); 954 preq_node->flags = flags; 955 956 mpath->flags |= MESH_PATH_REQ_QUEUED; 957 spin_unlock(&mpath->state_lock); 958 959 list_add_tail(&preq_node->list, &ifmsh->preq_queue.list); 960 ++ifmsh->preq_queue_len; 961 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock); 962 963 if (time_after(jiffies, ifmsh->last_preq + min_preq_int_jiff(sdata))) 964 ieee80211_queue_work(&sdata->local->hw, &sdata->work); 965 966 else if (time_before(jiffies, ifmsh->last_preq)) { 967 /* avoid long wait if did not send preqs for a long time 968 * and jiffies wrapped around 969 */ 970 ifmsh->last_preq = jiffies - min_preq_int_jiff(sdata) - 1; 971 ieee80211_queue_work(&sdata->local->hw, &sdata->work); 972 } else 973 mod_timer(&ifmsh->mesh_path_timer, ifmsh->last_preq + 974 min_preq_int_jiff(sdata)); 975 } 976 977 /** 978 * mesh_path_start_discovery - launch a path discovery from the PREQ queue 979 * 980 * @sdata: local mesh subif 981 */ 982 void mesh_path_start_discovery(struct ieee80211_sub_if_data *sdata) 983 { 984 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 985 struct mesh_preq_queue *preq_node; 986 struct mesh_path *mpath; 987 u8 ttl, target_flags; 988 const u8 *da; 989 u32 lifetime; 990 991 spin_lock_bh(&ifmsh->mesh_preq_queue_lock); 992 if (!ifmsh->preq_queue_len || 993 time_before(jiffies, ifmsh->last_preq + 994 min_preq_int_jiff(sdata))) { 995 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock); 996 return; 997 } 998 999 preq_node = list_first_entry(&ifmsh->preq_queue.list, 1000 struct mesh_preq_queue, list); 1001 list_del(&preq_node->list); 1002 --ifmsh->preq_queue_len; 1003 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock); 1004 1005 rcu_read_lock(); 1006 mpath = mesh_path_lookup(sdata, preq_node->dst); 1007 if (!mpath) 1008 goto enddiscovery; 1009 1010 spin_lock_bh(&mpath->state_lock); 1011 mpath->flags &= ~MESH_PATH_REQ_QUEUED; 1012 if (preq_node->flags & PREQ_Q_F_START) { 1013 if (mpath->flags & MESH_PATH_RESOLVING) { 1014 spin_unlock_bh(&mpath->state_lock); 1015 goto enddiscovery; 1016 } else { 1017 mpath->flags &= ~MESH_PATH_RESOLVED; 1018 mpath->flags |= MESH_PATH_RESOLVING; 1019 mpath->discovery_retries = 0; 1020 mpath->discovery_timeout = disc_timeout_jiff(sdata); 1021 } 1022 } else if (!(mpath->flags & MESH_PATH_RESOLVING) || 1023 mpath->flags & MESH_PATH_RESOLVED) { 1024 mpath->flags &= ~MESH_PATH_RESOLVING; 1025 spin_unlock_bh(&mpath->state_lock); 1026 goto enddiscovery; 1027 } 1028 1029 ifmsh->last_preq = jiffies; 1030 1031 if (time_after(jiffies, ifmsh->last_sn_update + 1032 net_traversal_jiffies(sdata)) || 1033 time_before(jiffies, ifmsh->last_sn_update)) { 1034 ++ifmsh->sn; 1035 sdata->u.mesh.last_sn_update = jiffies; 1036 } 1037 lifetime = default_lifetime(sdata); 1038 ttl = sdata->u.mesh.mshcfg.element_ttl; 1039 if (ttl == 0) { 1040 sdata->u.mesh.mshstats.dropped_frames_ttl++; 1041 spin_unlock_bh(&mpath->state_lock); 1042 goto enddiscovery; 1043 } 1044 1045 if (preq_node->flags & PREQ_Q_F_REFRESH) 1046 target_flags = MP_F_DO; 1047 else 1048 target_flags = MP_F_RF; 1049 1050 spin_unlock_bh(&mpath->state_lock); 1051 da = (mpath->is_root) ? mpath->rann_snd_addr : broadcast_addr; 1052 mesh_path_sel_frame_tx(MPATH_PREQ, 0, sdata->vif.addr, 1053 cpu_to_le32(ifmsh->sn), target_flags, mpath->dst, 1054 cpu_to_le32(mpath->sn), da, 0, 1055 ttl, cpu_to_le32(lifetime), 0, 1056 cpu_to_le32(ifmsh->preq_id++), sdata); 1057 mod_timer(&mpath->timer, jiffies + mpath->discovery_timeout); 1058 1059 enddiscovery: 1060 rcu_read_unlock(); 1061 kfree(preq_node); 1062 } 1063 1064 /** 1065 * mesh_nexthop_resolve - lookup next hop; conditionally start path discovery 1066 * 1067 * @skb: 802.11 frame to be sent 1068 * @sdata: network subif the frame will be sent through 1069 * 1070 * Lookup next hop for given skb and start path discovery if no 1071 * forwarding information is found. 1072 * 1073 * Returns: 0 if the next hop was found and -ENOENT if the frame was queued. 1074 * skb is freeed here if no mpath could be allocated. 1075 */ 1076 int mesh_nexthop_resolve(struct ieee80211_sub_if_data *sdata, 1077 struct sk_buff *skb) 1078 { 1079 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 1080 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 1081 struct mesh_path *mpath; 1082 struct sk_buff *skb_to_free = NULL; 1083 u8 *target_addr = hdr->addr3; 1084 int err = 0; 1085 1086 /* Nulls are only sent to peers for PS and should be pre-addressed */ 1087 if (ieee80211_is_qos_nullfunc(hdr->frame_control)) 1088 return 0; 1089 1090 rcu_read_lock(); 1091 err = mesh_nexthop_lookup(sdata, skb); 1092 if (!err) 1093 goto endlookup; 1094 1095 /* no nexthop found, start resolving */ 1096 mpath = mesh_path_lookup(sdata, target_addr); 1097 if (!mpath) { 1098 mpath = mesh_path_add(sdata, target_addr); 1099 if (IS_ERR(mpath)) { 1100 mesh_path_discard_frame(sdata, skb); 1101 err = PTR_ERR(mpath); 1102 goto endlookup; 1103 } 1104 } 1105 1106 if (!(mpath->flags & MESH_PATH_RESOLVING)) 1107 mesh_queue_preq(mpath, PREQ_Q_F_START); 1108 1109 if (skb_queue_len(&mpath->frame_queue) >= MESH_FRAME_QUEUE_LEN) 1110 skb_to_free = skb_dequeue(&mpath->frame_queue); 1111 1112 info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING; 1113 ieee80211_set_qos_hdr(sdata, skb); 1114 skb_queue_tail(&mpath->frame_queue, skb); 1115 err = -ENOENT; 1116 if (skb_to_free) 1117 mesh_path_discard_frame(sdata, skb_to_free); 1118 1119 endlookup: 1120 rcu_read_unlock(); 1121 return err; 1122 } 1123 1124 /** 1125 * mesh_nexthop_lookup - put the appropriate next hop on a mesh frame. Calling 1126 * this function is considered "using" the associated mpath, so preempt a path 1127 * refresh if this mpath expires soon. 1128 * 1129 * @skb: 802.11 frame to be sent 1130 * @sdata: network subif the frame will be sent through 1131 * 1132 * Returns: 0 if the next hop was found. Nonzero otherwise. 1133 */ 1134 int mesh_nexthop_lookup(struct ieee80211_sub_if_data *sdata, 1135 struct sk_buff *skb) 1136 { 1137 struct mesh_path *mpath; 1138 struct sta_info *next_hop; 1139 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 1140 u8 *target_addr = hdr->addr3; 1141 int err = -ENOENT; 1142 1143 rcu_read_lock(); 1144 mpath = mesh_path_lookup(sdata, target_addr); 1145 1146 if (!mpath || !(mpath->flags & MESH_PATH_ACTIVE)) 1147 goto endlookup; 1148 1149 if (time_after(jiffies, 1150 mpath->exp_time - 1151 msecs_to_jiffies(sdata->u.mesh.mshcfg.path_refresh_time)) && 1152 ether_addr_equal(sdata->vif.addr, hdr->addr4) && 1153 !(mpath->flags & MESH_PATH_RESOLVING) && 1154 !(mpath->flags & MESH_PATH_FIXED)) 1155 mesh_queue_preq(mpath, PREQ_Q_F_START | PREQ_Q_F_REFRESH); 1156 1157 next_hop = rcu_dereference(mpath->next_hop); 1158 if (next_hop) { 1159 memcpy(hdr->addr1, next_hop->sta.addr, ETH_ALEN); 1160 memcpy(hdr->addr2, sdata->vif.addr, ETH_ALEN); 1161 ieee80211_mps_set_frame_flags(sdata, next_hop, hdr); 1162 err = 0; 1163 } 1164 1165 endlookup: 1166 rcu_read_unlock(); 1167 return err; 1168 } 1169 1170 void mesh_path_timer(unsigned long data) 1171 { 1172 struct mesh_path *mpath = (void *) data; 1173 struct ieee80211_sub_if_data *sdata = mpath->sdata; 1174 int ret; 1175 1176 if (sdata->local->quiescing) 1177 return; 1178 1179 spin_lock_bh(&mpath->state_lock); 1180 if (mpath->flags & MESH_PATH_RESOLVED || 1181 (!(mpath->flags & MESH_PATH_RESOLVING))) { 1182 mpath->flags &= ~(MESH_PATH_RESOLVING | MESH_PATH_RESOLVED); 1183 spin_unlock_bh(&mpath->state_lock); 1184 } else if (mpath->discovery_retries < max_preq_retries(sdata)) { 1185 ++mpath->discovery_retries; 1186 mpath->discovery_timeout *= 2; 1187 mpath->flags &= ~MESH_PATH_REQ_QUEUED; 1188 spin_unlock_bh(&mpath->state_lock); 1189 mesh_queue_preq(mpath, 0); 1190 } else { 1191 mpath->flags = 0; 1192 mpath->exp_time = jiffies; 1193 spin_unlock_bh(&mpath->state_lock); 1194 if (!mpath->is_gate && mesh_gate_num(sdata) > 0) { 1195 ret = mesh_path_send_to_gates(mpath); 1196 if (ret) 1197 mhwmp_dbg(sdata, "no gate was reachable\n"); 1198 } else 1199 mesh_path_flush_pending(mpath); 1200 } 1201 } 1202 1203 void mesh_path_tx_root_frame(struct ieee80211_sub_if_data *sdata) 1204 { 1205 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 1206 u32 interval = ifmsh->mshcfg.dot11MeshHWMPRannInterval; 1207 u8 flags, target_flags = 0; 1208 1209 flags = (ifmsh->mshcfg.dot11MeshGateAnnouncementProtocol) 1210 ? RANN_FLAG_IS_GATE : 0; 1211 1212 switch (ifmsh->mshcfg.dot11MeshHWMPRootMode) { 1213 case IEEE80211_PROACTIVE_RANN: 1214 mesh_path_sel_frame_tx(MPATH_RANN, flags, sdata->vif.addr, 1215 cpu_to_le32(++ifmsh->sn), 1216 0, NULL, 0, broadcast_addr, 1217 0, ifmsh->mshcfg.element_ttl, 1218 cpu_to_le32(interval), 0, 0, sdata); 1219 break; 1220 case IEEE80211_PROACTIVE_PREQ_WITH_PREP: 1221 flags |= IEEE80211_PREQ_PROACTIVE_PREP_FLAG; 1222 case IEEE80211_PROACTIVE_PREQ_NO_PREP: 1223 interval = ifmsh->mshcfg.dot11MeshHWMPactivePathToRootTimeout; 1224 target_flags |= IEEE80211_PREQ_TO_FLAG | 1225 IEEE80211_PREQ_USN_FLAG; 1226 mesh_path_sel_frame_tx(MPATH_PREQ, flags, sdata->vif.addr, 1227 cpu_to_le32(++ifmsh->sn), target_flags, 1228 (u8 *) broadcast_addr, 0, broadcast_addr, 1229 0, ifmsh->mshcfg.element_ttl, 1230 cpu_to_le32(interval), 1231 0, cpu_to_le32(ifmsh->preq_id++), sdata); 1232 break; 1233 default: 1234 mhwmp_dbg(sdata, "Proactive mechanism not supported\n"); 1235 return; 1236 } 1237 } 1238