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