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 static void mesh_queue_preq(struct mesh_path *, u8); 23 24 static inline u32 u32_field_get(const u8 *preq_elem, int offset, bool ae) 25 { 26 if (ae) 27 offset += 6; 28 return get_unaligned_le32(preq_elem + offset); 29 } 30 31 static inline u16 u16_field_get(const u8 *preq_elem, int offset, bool ae) 32 { 33 if (ae) 34 offset += 6; 35 return get_unaligned_le16(preq_elem + offset); 36 } 37 38 /* HWMP IE processing macros */ 39 #define AE_F (1<<6) 40 #define AE_F_SET(x) (*x & AE_F) 41 #define PREQ_IE_FLAGS(x) (*(x)) 42 #define PREQ_IE_HOPCOUNT(x) (*(x + 1)) 43 #define PREQ_IE_TTL(x) (*(x + 2)) 44 #define PREQ_IE_PREQ_ID(x) u32_field_get(x, 3, 0) 45 #define PREQ_IE_ORIG_ADDR(x) (x + 7) 46 #define PREQ_IE_ORIG_SN(x) u32_field_get(x, 13, 0) 47 #define PREQ_IE_LIFETIME(x) u32_field_get(x, 17, AE_F_SET(x)) 48 #define PREQ_IE_METRIC(x) u32_field_get(x, 21, AE_F_SET(x)) 49 #define PREQ_IE_TARGET_F(x) (*(AE_F_SET(x) ? x + 32 : x + 26)) 50 #define PREQ_IE_TARGET_ADDR(x) (AE_F_SET(x) ? x + 33 : x + 27) 51 #define PREQ_IE_TARGET_SN(x) u32_field_get(x, 33, AE_F_SET(x)) 52 53 54 #define PREP_IE_FLAGS(x) PREQ_IE_FLAGS(x) 55 #define PREP_IE_HOPCOUNT(x) PREQ_IE_HOPCOUNT(x) 56 #define PREP_IE_TTL(x) PREQ_IE_TTL(x) 57 #define PREP_IE_ORIG_ADDR(x) (AE_F_SET(x) ? x + 27 : x + 21) 58 #define PREP_IE_ORIG_SN(x) u32_field_get(x, 27, AE_F_SET(x)) 59 #define PREP_IE_LIFETIME(x) u32_field_get(x, 13, AE_F_SET(x)) 60 #define PREP_IE_METRIC(x) u32_field_get(x, 17, AE_F_SET(x)) 61 #define PREP_IE_TARGET_ADDR(x) (x + 3) 62 #define PREP_IE_TARGET_SN(x) u32_field_get(x, 9, 0) 63 64 #define PERR_IE_TTL(x) (*(x)) 65 #define PERR_IE_TARGET_FLAGS(x) (*(x + 2)) 66 #define PERR_IE_TARGET_ADDR(x) (x + 3) 67 #define PERR_IE_TARGET_SN(x) u32_field_get(x, 9, 0) 68 #define PERR_IE_TARGET_RCODE(x) u16_field_get(x, 13, 0) 69 70 #define MSEC_TO_TU(x) (x*1000/1024) 71 #define SN_GT(x, y) ((s32)(y - x) < 0) 72 #define SN_LT(x, y) ((s32)(x - y) < 0) 73 #define MAX_SANE_SN_DELTA 32 74 75 static inline u32 SN_DELTA(u32 x, u32 y) 76 { 77 return x >= y ? x - y : y - x; 78 } 79 80 #define net_traversal_jiffies(s) \ 81 msecs_to_jiffies(s->u.mesh.mshcfg.dot11MeshHWMPnetDiameterTraversalTime) 82 #define default_lifetime(s) \ 83 MSEC_TO_TU(s->u.mesh.mshcfg.dot11MeshHWMPactivePathTimeout) 84 #define min_preq_int_jiff(s) \ 85 (msecs_to_jiffies(s->u.mesh.mshcfg.dot11MeshHWMPpreqMinInterval)) 86 #define max_preq_retries(s) (s->u.mesh.mshcfg.dot11MeshHWMPmaxPREQretries) 87 #define disc_timeout_jiff(s) \ 88 msecs_to_jiffies(sdata->u.mesh.mshcfg.min_discovery_timeout) 89 #define root_path_confirmation_jiffies(s) \ 90 msecs_to_jiffies(sdata->u.mesh.mshcfg.dot11MeshHWMPconfirmationInterval) 91 92 enum mpath_frame_type { 93 MPATH_PREQ = 0, 94 MPATH_PREP, 95 MPATH_PERR, 96 MPATH_RANN 97 }; 98 99 static const u8 broadcast_addr[ETH_ALEN] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff}; 100 101 static int mesh_path_sel_frame_tx(enum mpath_frame_type action, u8 flags, 102 const u8 *orig_addr, u32 orig_sn, 103 u8 target_flags, const u8 *target, 104 u32 target_sn, const u8 *da, 105 u8 hop_count, u8 ttl, 106 u32 lifetime, u32 metric, u32 preq_id, 107 struct ieee80211_sub_if_data *sdata) 108 { 109 struct ieee80211_local *local = sdata->local; 110 struct sk_buff *skb; 111 struct ieee80211_mgmt *mgmt; 112 u8 *pos, ie_len; 113 int hdr_len = offsetof(struct ieee80211_mgmt, u.action.u.mesh_action) + 114 sizeof(mgmt->u.action.u.mesh_action); 115 116 skb = dev_alloc_skb(local->tx_headroom + 117 hdr_len + 118 2 + 37); /* max HWMP IE */ 119 if (!skb) 120 return -1; 121 skb_reserve(skb, local->tx_headroom); 122 mgmt = (struct ieee80211_mgmt *) skb_put(skb, hdr_len); 123 memset(mgmt, 0, hdr_len); 124 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 125 IEEE80211_STYPE_ACTION); 126 127 memcpy(mgmt->da, da, ETH_ALEN); 128 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN); 129 /* BSSID == SA */ 130 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN); 131 mgmt->u.action.category = WLAN_CATEGORY_MESH_ACTION; 132 mgmt->u.action.u.mesh_action.action_code = 133 WLAN_MESH_ACTION_HWMP_PATH_SELECTION; 134 135 switch (action) { 136 case MPATH_PREQ: 137 mhwmp_dbg(sdata, "sending PREQ to %pM\n", target); 138 ie_len = 37; 139 pos = skb_put(skb, 2 + ie_len); 140 *pos++ = WLAN_EID_PREQ; 141 break; 142 case MPATH_PREP: 143 mhwmp_dbg(sdata, "sending PREP to %pM\n", orig_addr); 144 ie_len = 31; 145 pos = skb_put(skb, 2 + ie_len); 146 *pos++ = WLAN_EID_PREP; 147 break; 148 case MPATH_RANN: 149 mhwmp_dbg(sdata, "sending RANN from %pM\n", orig_addr); 150 ie_len = sizeof(struct ieee80211_rann_ie); 151 pos = skb_put(skb, 2 + ie_len); 152 *pos++ = WLAN_EID_RANN; 153 break; 154 default: 155 kfree_skb(skb); 156 return -ENOTSUPP; 157 } 158 *pos++ = ie_len; 159 *pos++ = flags; 160 *pos++ = hop_count; 161 *pos++ = ttl; 162 if (action == MPATH_PREP) { 163 memcpy(pos, target, ETH_ALEN); 164 pos += ETH_ALEN; 165 put_unaligned_le32(target_sn, pos); 166 pos += 4; 167 } else { 168 if (action == MPATH_PREQ) { 169 put_unaligned_le32(preq_id, pos); 170 pos += 4; 171 } 172 memcpy(pos, orig_addr, ETH_ALEN); 173 pos += ETH_ALEN; 174 put_unaligned_le32(orig_sn, pos); 175 pos += 4; 176 } 177 put_unaligned_le32(lifetime, pos); /* interval for RANN */ 178 pos += 4; 179 put_unaligned_le32(metric, pos); 180 pos += 4; 181 if (action == MPATH_PREQ) { 182 *pos++ = 1; /* destination count */ 183 *pos++ = target_flags; 184 memcpy(pos, target, ETH_ALEN); 185 pos += ETH_ALEN; 186 put_unaligned_le32(target_sn, pos); 187 pos += 4; 188 } else if (action == MPATH_PREP) { 189 memcpy(pos, orig_addr, ETH_ALEN); 190 pos += ETH_ALEN; 191 put_unaligned_le32(orig_sn, pos); 192 pos += 4; 193 } 194 195 ieee80211_tx_skb(sdata, skb); 196 return 0; 197 } 198 199 200 /* Headroom is not adjusted. Caller should ensure that skb has sufficient 201 * headroom in case the frame is encrypted. */ 202 static void prepare_frame_for_deferred_tx(struct ieee80211_sub_if_data *sdata, 203 struct sk_buff *skb) 204 { 205 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 206 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 207 208 skb_reset_mac_header(skb); 209 skb_reset_network_header(skb); 210 skb_reset_transport_header(skb); 211 212 /* Send all internal mgmt frames on VO. Accordingly set TID to 7. */ 213 skb_set_queue_mapping(skb, IEEE80211_AC_VO); 214 skb->priority = 7; 215 216 info->control.vif = &sdata->vif; 217 info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING; 218 ieee80211_set_qos_hdr(sdata, skb); 219 ieee80211_mps_set_frame_flags(sdata, NULL, hdr); 220 } 221 222 /** 223 * mesh_path_error_tx - Sends a PERR mesh management frame 224 * 225 * @ttl: allowed remaining hops 226 * @target: broken destination 227 * @target_sn: SN of the broken destination 228 * @target_rcode: reason code for this PERR 229 * @ra: node this frame is addressed to 230 * @sdata: local mesh subif 231 * 232 * Note: This function may be called with driver locks taken that the driver 233 * also acquires in the TX path. To avoid a deadlock we don't transmit the 234 * frame directly but add it to the pending queue instead. 235 */ 236 int mesh_path_error_tx(struct ieee80211_sub_if_data *sdata, 237 u8 ttl, const u8 *target, u32 target_sn, 238 u16 target_rcode, const u8 *ra) 239 { 240 struct ieee80211_local *local = sdata->local; 241 struct sk_buff *skb; 242 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 243 struct ieee80211_mgmt *mgmt; 244 u8 *pos, ie_len; 245 int hdr_len = offsetof(struct ieee80211_mgmt, u.action.u.mesh_action) + 246 sizeof(mgmt->u.action.u.mesh_action); 247 248 if (time_before(jiffies, ifmsh->next_perr)) 249 return -EAGAIN; 250 251 skb = dev_alloc_skb(local->tx_headroom + 252 sdata->encrypt_headroom + 253 IEEE80211_ENCRYPT_TAILROOM + 254 hdr_len + 255 2 + 15 /* PERR IE */); 256 if (!skb) 257 return -1; 258 skb_reserve(skb, local->tx_headroom + sdata->encrypt_headroom); 259 mgmt = (struct ieee80211_mgmt *) skb_put(skb, hdr_len); 260 memset(mgmt, 0, hdr_len); 261 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 262 IEEE80211_STYPE_ACTION); 263 264 memcpy(mgmt->da, ra, ETH_ALEN); 265 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN); 266 /* BSSID == SA */ 267 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN); 268 mgmt->u.action.category = WLAN_CATEGORY_MESH_ACTION; 269 mgmt->u.action.u.mesh_action.action_code = 270 WLAN_MESH_ACTION_HWMP_PATH_SELECTION; 271 ie_len = 15; 272 pos = skb_put(skb, 2 + ie_len); 273 *pos++ = WLAN_EID_PERR; 274 *pos++ = ie_len; 275 /* ttl */ 276 *pos++ = ttl; 277 /* number of destinations */ 278 *pos++ = 1; 279 /* Flags field has AE bit only as defined in 280 * sec 8.4.2.117 IEEE802.11-2012 281 */ 282 *pos = 0; 283 pos++; 284 memcpy(pos, target, ETH_ALEN); 285 pos += ETH_ALEN; 286 put_unaligned_le32(target_sn, pos); 287 pos += 4; 288 put_unaligned_le16(target_rcode, pos); 289 290 /* see note in function header */ 291 prepare_frame_for_deferred_tx(sdata, skb); 292 ifmsh->next_perr = TU_TO_EXP_TIME( 293 ifmsh->mshcfg.dot11MeshHWMPperrMinInterval); 294 ieee80211_add_pending_skb(local, skb); 295 return 0; 296 } 297 298 void ieee80211s_update_metric(struct ieee80211_local *local, 299 struct sta_info *sta, struct sk_buff *skb) 300 { 301 struct ieee80211_tx_info *txinfo = IEEE80211_SKB_CB(skb); 302 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 303 int failed; 304 305 if (!ieee80211_is_data(hdr->frame_control)) 306 return; 307 308 failed = !(txinfo->flags & IEEE80211_TX_STAT_ACK); 309 310 /* moving average, scaled to 100 */ 311 sta->mesh->fail_avg = 312 ((80 * sta->mesh->fail_avg + 5) / 100 + 20 * failed); 313 if (sta->mesh->fail_avg > 95) 314 mesh_plink_broken(sta); 315 } 316 317 static u32 airtime_link_metric_get(struct ieee80211_local *local, 318 struct sta_info *sta) 319 { 320 struct rate_info rinfo; 321 /* This should be adjusted for each device */ 322 int device_constant = 1 << ARITH_SHIFT; 323 int test_frame_len = TEST_FRAME_LEN << ARITH_SHIFT; 324 int s_unit = 1 << ARITH_SHIFT; 325 int rate, err; 326 u32 tx_time, estimated_retx; 327 u64 result; 328 329 /* Try to get rate based on HW/SW RC algorithm. 330 * Rate is returned in units of Kbps, correct this 331 * to comply with airtime calculation units 332 * Round up in case we get rate < 100Kbps 333 */ 334 rate = DIV_ROUND_UP(sta_get_expected_throughput(sta), 100); 335 336 if (rate) { 337 err = 0; 338 } else { 339 if (sta->mesh->fail_avg >= 100) 340 return MAX_METRIC; 341 342 sta_set_rate_info_tx(sta, &sta->tx_stats.last_rate, &rinfo); 343 rate = cfg80211_calculate_bitrate(&rinfo); 344 if (WARN_ON(!rate)) 345 return MAX_METRIC; 346 347 err = (sta->mesh->fail_avg << ARITH_SHIFT) / 100; 348 } 349 350 /* bitrate is in units of 100 Kbps, while we need rate in units of 351 * 1Mbps. This will be corrected on tx_time computation. 352 */ 353 tx_time = (device_constant + 10 * test_frame_len / rate); 354 estimated_retx = ((1 << (2 * ARITH_SHIFT)) / (s_unit - err)); 355 result = (tx_time * estimated_retx) >> (2 * ARITH_SHIFT); 356 return (u32)result; 357 } 358 359 /** 360 * hwmp_route_info_get - Update routing info to originator and transmitter 361 * 362 * @sdata: local mesh subif 363 * @mgmt: mesh management frame 364 * @hwmp_ie: hwmp information element (PREP or PREQ) 365 * @action: type of hwmp ie 366 * 367 * This function updates the path routing information to the originator and the 368 * transmitter of a HWMP PREQ or PREP frame. 369 * 370 * Returns: metric to frame originator or 0 if the frame should not be further 371 * processed 372 * 373 * Notes: this function is the only place (besides user-provided info) where 374 * path routing information is updated. 375 */ 376 static u32 hwmp_route_info_get(struct ieee80211_sub_if_data *sdata, 377 struct ieee80211_mgmt *mgmt, 378 const u8 *hwmp_ie, enum mpath_frame_type action) 379 { 380 struct ieee80211_local *local = sdata->local; 381 struct mesh_path *mpath; 382 struct sta_info *sta; 383 bool fresh_info; 384 const u8 *orig_addr, *ta; 385 u32 orig_sn, orig_metric; 386 unsigned long orig_lifetime, exp_time; 387 u32 last_hop_metric, new_metric; 388 bool process = true; 389 390 rcu_read_lock(); 391 sta = sta_info_get(sdata, mgmt->sa); 392 if (!sta) { 393 rcu_read_unlock(); 394 return 0; 395 } 396 397 last_hop_metric = airtime_link_metric_get(local, sta); 398 /* Update and check originator routing info */ 399 fresh_info = true; 400 401 switch (action) { 402 case MPATH_PREQ: 403 orig_addr = PREQ_IE_ORIG_ADDR(hwmp_ie); 404 orig_sn = PREQ_IE_ORIG_SN(hwmp_ie); 405 orig_lifetime = PREQ_IE_LIFETIME(hwmp_ie); 406 orig_metric = PREQ_IE_METRIC(hwmp_ie); 407 break; 408 case MPATH_PREP: 409 /* Originator here refers to the MP that was the target in the 410 * Path Request. We divert from the nomenclature in the draft 411 * so that we can easily use a single function to gather path 412 * information from both PREQ and PREP frames. 413 */ 414 orig_addr = PREP_IE_TARGET_ADDR(hwmp_ie); 415 orig_sn = PREP_IE_TARGET_SN(hwmp_ie); 416 orig_lifetime = PREP_IE_LIFETIME(hwmp_ie); 417 orig_metric = PREP_IE_METRIC(hwmp_ie); 418 break; 419 default: 420 rcu_read_unlock(); 421 return 0; 422 } 423 new_metric = orig_metric + last_hop_metric; 424 if (new_metric < orig_metric) 425 new_metric = MAX_METRIC; 426 exp_time = TU_TO_EXP_TIME(orig_lifetime); 427 428 if (ether_addr_equal(orig_addr, sdata->vif.addr)) { 429 /* This MP is the originator, we are not interested in this 430 * frame, except for updating transmitter's path info. 431 */ 432 process = false; 433 fresh_info = false; 434 } else { 435 mpath = mesh_path_lookup(sdata, orig_addr); 436 if (mpath) { 437 spin_lock_bh(&mpath->state_lock); 438 if (mpath->flags & MESH_PATH_FIXED) 439 fresh_info = false; 440 else if ((mpath->flags & MESH_PATH_ACTIVE) && 441 (mpath->flags & MESH_PATH_SN_VALID)) { 442 if (SN_GT(mpath->sn, orig_sn) || 443 (mpath->sn == orig_sn && 444 new_metric >= mpath->metric)) { 445 process = false; 446 fresh_info = false; 447 } 448 } else if (!(mpath->flags & MESH_PATH_ACTIVE)) { 449 bool have_sn, newer_sn, bounced; 450 451 have_sn = mpath->flags & MESH_PATH_SN_VALID; 452 newer_sn = have_sn && SN_GT(orig_sn, mpath->sn); 453 bounced = have_sn && 454 (SN_DELTA(orig_sn, mpath->sn) > 455 MAX_SANE_SN_DELTA); 456 457 if (!have_sn || newer_sn) { 458 /* if SN is newer than what we had 459 * then we can take it */; 460 } else if (bounced) { 461 /* if SN is way different than what 462 * we had then assume the other side 463 * rebooted or restarted */; 464 } else { 465 process = false; 466 fresh_info = false; 467 } 468 } 469 } else { 470 mpath = mesh_path_add(sdata, orig_addr); 471 if (IS_ERR(mpath)) { 472 rcu_read_unlock(); 473 return 0; 474 } 475 spin_lock_bh(&mpath->state_lock); 476 } 477 478 if (fresh_info) { 479 mesh_path_assign_nexthop(mpath, sta); 480 mpath->flags |= MESH_PATH_SN_VALID; 481 mpath->metric = new_metric; 482 mpath->sn = orig_sn; 483 mpath->exp_time = time_after(mpath->exp_time, exp_time) 484 ? mpath->exp_time : exp_time; 485 mesh_path_activate(mpath); 486 spin_unlock_bh(&mpath->state_lock); 487 mesh_path_tx_pending(mpath); 488 /* draft says preq_id should be saved to, but there does 489 * not seem to be any use for it, skipping by now 490 */ 491 } else 492 spin_unlock_bh(&mpath->state_lock); 493 } 494 495 /* Update and check transmitter routing info */ 496 ta = mgmt->sa; 497 if (ether_addr_equal(orig_addr, ta)) 498 fresh_info = false; 499 else { 500 fresh_info = true; 501 502 mpath = mesh_path_lookup(sdata, ta); 503 if (mpath) { 504 spin_lock_bh(&mpath->state_lock); 505 if ((mpath->flags & MESH_PATH_FIXED) || 506 ((mpath->flags & MESH_PATH_ACTIVE) && 507 (last_hop_metric > mpath->metric))) 508 fresh_info = false; 509 } else { 510 mpath = mesh_path_add(sdata, ta); 511 if (IS_ERR(mpath)) { 512 rcu_read_unlock(); 513 return 0; 514 } 515 spin_lock_bh(&mpath->state_lock); 516 } 517 518 if (fresh_info) { 519 mesh_path_assign_nexthop(mpath, sta); 520 mpath->metric = last_hop_metric; 521 mpath->exp_time = time_after(mpath->exp_time, exp_time) 522 ? mpath->exp_time : exp_time; 523 mesh_path_activate(mpath); 524 spin_unlock_bh(&mpath->state_lock); 525 mesh_path_tx_pending(mpath); 526 } else 527 spin_unlock_bh(&mpath->state_lock); 528 } 529 530 rcu_read_unlock(); 531 532 return process ? new_metric : 0; 533 } 534 535 static void hwmp_preq_frame_process(struct ieee80211_sub_if_data *sdata, 536 struct ieee80211_mgmt *mgmt, 537 const u8 *preq_elem, u32 orig_metric) 538 { 539 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 540 struct mesh_path *mpath = NULL; 541 const u8 *target_addr, *orig_addr; 542 const u8 *da; 543 u8 target_flags, ttl, flags; 544 u32 orig_sn, target_sn, lifetime, target_metric = 0; 545 bool reply = false; 546 bool forward = true; 547 bool root_is_gate; 548 549 /* Update target SN, if present */ 550 target_addr = PREQ_IE_TARGET_ADDR(preq_elem); 551 orig_addr = PREQ_IE_ORIG_ADDR(preq_elem); 552 target_sn = PREQ_IE_TARGET_SN(preq_elem); 553 orig_sn = PREQ_IE_ORIG_SN(preq_elem); 554 target_flags = PREQ_IE_TARGET_F(preq_elem); 555 /* Proactive PREQ gate announcements */ 556 flags = PREQ_IE_FLAGS(preq_elem); 557 root_is_gate = !!(flags & RANN_FLAG_IS_GATE); 558 559 mhwmp_dbg(sdata, "received PREQ from %pM\n", orig_addr); 560 561 if (ether_addr_equal(target_addr, sdata->vif.addr)) { 562 mhwmp_dbg(sdata, "PREQ is for us\n"); 563 forward = false; 564 reply = true; 565 target_metric = 0; 566 if (time_after(jiffies, ifmsh->last_sn_update + 567 net_traversal_jiffies(sdata)) || 568 time_before(jiffies, ifmsh->last_sn_update)) { 569 ++ifmsh->sn; 570 ifmsh->last_sn_update = jiffies; 571 } 572 target_sn = ifmsh->sn; 573 } else if (is_broadcast_ether_addr(target_addr) && 574 (target_flags & IEEE80211_PREQ_TO_FLAG)) { 575 rcu_read_lock(); 576 mpath = mesh_path_lookup(sdata, orig_addr); 577 if (mpath) { 578 if (flags & IEEE80211_PREQ_PROACTIVE_PREP_FLAG) { 579 reply = true; 580 target_addr = sdata->vif.addr; 581 target_sn = ++ifmsh->sn; 582 target_metric = 0; 583 ifmsh->last_sn_update = jiffies; 584 } 585 if (root_is_gate) 586 mesh_path_add_gate(mpath); 587 } 588 rcu_read_unlock(); 589 } else { 590 rcu_read_lock(); 591 mpath = mesh_path_lookup(sdata, target_addr); 592 if (mpath) { 593 if ((!(mpath->flags & MESH_PATH_SN_VALID)) || 594 SN_LT(mpath->sn, target_sn)) { 595 mpath->sn = target_sn; 596 mpath->flags |= MESH_PATH_SN_VALID; 597 } else if ((!(target_flags & IEEE80211_PREQ_TO_FLAG)) && 598 (mpath->flags & MESH_PATH_ACTIVE)) { 599 reply = true; 600 target_metric = mpath->metric; 601 target_sn = mpath->sn; 602 /* Case E2 of sec 13.10.9.3 IEEE 802.11-2012*/ 603 target_flags |= IEEE80211_PREQ_TO_FLAG; 604 } 605 } 606 rcu_read_unlock(); 607 } 608 609 if (reply) { 610 lifetime = PREQ_IE_LIFETIME(preq_elem); 611 ttl = ifmsh->mshcfg.element_ttl; 612 if (ttl != 0) { 613 mhwmp_dbg(sdata, "replying to the PREQ\n"); 614 mesh_path_sel_frame_tx(MPATH_PREP, 0, orig_addr, 615 orig_sn, 0, target_addr, 616 target_sn, mgmt->sa, 0, ttl, 617 lifetime, target_metric, 0, 618 sdata); 619 } else { 620 ifmsh->mshstats.dropped_frames_ttl++; 621 } 622 } 623 624 if (forward && ifmsh->mshcfg.dot11MeshForwarding) { 625 u32 preq_id; 626 u8 hopcount; 627 628 ttl = PREQ_IE_TTL(preq_elem); 629 lifetime = PREQ_IE_LIFETIME(preq_elem); 630 if (ttl <= 1) { 631 ifmsh->mshstats.dropped_frames_ttl++; 632 return; 633 } 634 mhwmp_dbg(sdata, "forwarding the PREQ from %pM\n", orig_addr); 635 --ttl; 636 preq_id = PREQ_IE_PREQ_ID(preq_elem); 637 hopcount = PREQ_IE_HOPCOUNT(preq_elem) + 1; 638 da = (mpath && mpath->is_root) ? 639 mpath->rann_snd_addr : broadcast_addr; 640 641 if (flags & IEEE80211_PREQ_PROACTIVE_PREP_FLAG) { 642 target_addr = PREQ_IE_TARGET_ADDR(preq_elem); 643 target_sn = PREQ_IE_TARGET_SN(preq_elem); 644 } 645 646 mesh_path_sel_frame_tx(MPATH_PREQ, flags, orig_addr, 647 orig_sn, target_flags, target_addr, 648 target_sn, da, hopcount, ttl, lifetime, 649 orig_metric, preq_id, sdata); 650 if (!is_multicast_ether_addr(da)) 651 ifmsh->mshstats.fwded_unicast++; 652 else 653 ifmsh->mshstats.fwded_mcast++; 654 ifmsh->mshstats.fwded_frames++; 655 } 656 } 657 658 659 static inline struct sta_info * 660 next_hop_deref_protected(struct mesh_path *mpath) 661 { 662 return rcu_dereference_protected(mpath->next_hop, 663 lockdep_is_held(&mpath->state_lock)); 664 } 665 666 667 static void hwmp_prep_frame_process(struct ieee80211_sub_if_data *sdata, 668 struct ieee80211_mgmt *mgmt, 669 const u8 *prep_elem, u32 metric) 670 { 671 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 672 struct mesh_path *mpath; 673 const u8 *target_addr, *orig_addr; 674 u8 ttl, hopcount, flags; 675 u8 next_hop[ETH_ALEN]; 676 u32 target_sn, orig_sn, lifetime; 677 678 mhwmp_dbg(sdata, "received PREP from %pM\n", 679 PREP_IE_TARGET_ADDR(prep_elem)); 680 681 orig_addr = PREP_IE_ORIG_ADDR(prep_elem); 682 if (ether_addr_equal(orig_addr, sdata->vif.addr)) 683 /* destination, no forwarding required */ 684 return; 685 686 if (!ifmsh->mshcfg.dot11MeshForwarding) 687 return; 688 689 ttl = PREP_IE_TTL(prep_elem); 690 if (ttl <= 1) { 691 sdata->u.mesh.mshstats.dropped_frames_ttl++; 692 return; 693 } 694 695 rcu_read_lock(); 696 mpath = mesh_path_lookup(sdata, orig_addr); 697 if (mpath) 698 spin_lock_bh(&mpath->state_lock); 699 else 700 goto fail; 701 if (!(mpath->flags & MESH_PATH_ACTIVE)) { 702 spin_unlock_bh(&mpath->state_lock); 703 goto fail; 704 } 705 memcpy(next_hop, next_hop_deref_protected(mpath)->sta.addr, ETH_ALEN); 706 spin_unlock_bh(&mpath->state_lock); 707 --ttl; 708 flags = PREP_IE_FLAGS(prep_elem); 709 lifetime = PREP_IE_LIFETIME(prep_elem); 710 hopcount = PREP_IE_HOPCOUNT(prep_elem) + 1; 711 target_addr = PREP_IE_TARGET_ADDR(prep_elem); 712 target_sn = PREP_IE_TARGET_SN(prep_elem); 713 orig_sn = PREP_IE_ORIG_SN(prep_elem); 714 715 mesh_path_sel_frame_tx(MPATH_PREP, flags, orig_addr, orig_sn, 0, 716 target_addr, target_sn, next_hop, hopcount, 717 ttl, lifetime, metric, 0, sdata); 718 rcu_read_unlock(); 719 720 sdata->u.mesh.mshstats.fwded_unicast++; 721 sdata->u.mesh.mshstats.fwded_frames++; 722 return; 723 724 fail: 725 rcu_read_unlock(); 726 sdata->u.mesh.mshstats.dropped_frames_no_route++; 727 } 728 729 static void hwmp_perr_frame_process(struct ieee80211_sub_if_data *sdata, 730 struct ieee80211_mgmt *mgmt, 731 const u8 *perr_elem) 732 { 733 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 734 struct mesh_path *mpath; 735 u8 ttl; 736 const u8 *ta, *target_addr; 737 u32 target_sn; 738 u16 target_rcode; 739 740 ta = mgmt->sa; 741 ttl = PERR_IE_TTL(perr_elem); 742 if (ttl <= 1) { 743 ifmsh->mshstats.dropped_frames_ttl++; 744 return; 745 } 746 ttl--; 747 target_addr = PERR_IE_TARGET_ADDR(perr_elem); 748 target_sn = PERR_IE_TARGET_SN(perr_elem); 749 target_rcode = PERR_IE_TARGET_RCODE(perr_elem); 750 751 rcu_read_lock(); 752 mpath = mesh_path_lookup(sdata, target_addr); 753 if (mpath) { 754 struct sta_info *sta; 755 756 spin_lock_bh(&mpath->state_lock); 757 sta = next_hop_deref_protected(mpath); 758 if (mpath->flags & MESH_PATH_ACTIVE && 759 ether_addr_equal(ta, sta->sta.addr) && 760 (!(mpath->flags & MESH_PATH_SN_VALID) || 761 SN_GT(target_sn, mpath->sn) || target_sn == 0)) { 762 mpath->flags &= ~MESH_PATH_ACTIVE; 763 if (target_sn != 0) 764 mpath->sn = target_sn; 765 else 766 mpath->sn += 1; 767 spin_unlock_bh(&mpath->state_lock); 768 if (!ifmsh->mshcfg.dot11MeshForwarding) 769 goto endperr; 770 mesh_path_error_tx(sdata, ttl, target_addr, 771 target_sn, target_rcode, 772 broadcast_addr); 773 } else 774 spin_unlock_bh(&mpath->state_lock); 775 } 776 endperr: 777 rcu_read_unlock(); 778 } 779 780 static void hwmp_rann_frame_process(struct ieee80211_sub_if_data *sdata, 781 struct ieee80211_mgmt *mgmt, 782 const struct ieee80211_rann_ie *rann) 783 { 784 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 785 struct ieee80211_local *local = sdata->local; 786 struct sta_info *sta; 787 struct mesh_path *mpath; 788 u8 ttl, flags, hopcount; 789 const u8 *orig_addr; 790 u32 orig_sn, metric, metric_txsta, interval; 791 bool root_is_gate; 792 793 ttl = rann->rann_ttl; 794 flags = rann->rann_flags; 795 root_is_gate = !!(flags & RANN_FLAG_IS_GATE); 796 orig_addr = rann->rann_addr; 797 orig_sn = le32_to_cpu(rann->rann_seq); 798 interval = le32_to_cpu(rann->rann_interval); 799 hopcount = rann->rann_hopcount; 800 hopcount++; 801 metric = le32_to_cpu(rann->rann_metric); 802 803 /* Ignore our own RANNs */ 804 if (ether_addr_equal(orig_addr, sdata->vif.addr)) 805 return; 806 807 mhwmp_dbg(sdata, 808 "received RANN from %pM via neighbour %pM (is_gate=%d)\n", 809 orig_addr, mgmt->sa, root_is_gate); 810 811 rcu_read_lock(); 812 sta = sta_info_get(sdata, mgmt->sa); 813 if (!sta) { 814 rcu_read_unlock(); 815 return; 816 } 817 818 metric_txsta = airtime_link_metric_get(local, sta); 819 820 mpath = mesh_path_lookup(sdata, orig_addr); 821 if (!mpath) { 822 mpath = mesh_path_add(sdata, orig_addr); 823 if (IS_ERR(mpath)) { 824 rcu_read_unlock(); 825 sdata->u.mesh.mshstats.dropped_frames_no_route++; 826 return; 827 } 828 } 829 830 if (!(SN_LT(mpath->sn, orig_sn)) && 831 !(mpath->sn == orig_sn && metric < mpath->rann_metric)) { 832 rcu_read_unlock(); 833 return; 834 } 835 836 if ((!(mpath->flags & (MESH_PATH_ACTIVE | MESH_PATH_RESOLVING)) || 837 (time_after(jiffies, mpath->last_preq_to_root + 838 root_path_confirmation_jiffies(sdata)) || 839 time_before(jiffies, mpath->last_preq_to_root))) && 840 !(mpath->flags & MESH_PATH_FIXED) && (ttl != 0)) { 841 mhwmp_dbg(sdata, 842 "time to refresh root mpath %pM\n", 843 orig_addr); 844 mesh_queue_preq(mpath, PREQ_Q_F_START | PREQ_Q_F_REFRESH); 845 mpath->last_preq_to_root = jiffies; 846 } 847 848 mpath->sn = orig_sn; 849 mpath->rann_metric = metric + metric_txsta; 850 mpath->is_root = true; 851 /* Recording RANNs sender address to send individually 852 * addressed PREQs destined for root mesh STA */ 853 memcpy(mpath->rann_snd_addr, mgmt->sa, ETH_ALEN); 854 855 if (root_is_gate) 856 mesh_path_add_gate(mpath); 857 858 if (ttl <= 1) { 859 ifmsh->mshstats.dropped_frames_ttl++; 860 rcu_read_unlock(); 861 return; 862 } 863 ttl--; 864 865 if (ifmsh->mshcfg.dot11MeshForwarding) { 866 mesh_path_sel_frame_tx(MPATH_RANN, flags, orig_addr, 867 orig_sn, 0, NULL, 0, broadcast_addr, 868 hopcount, ttl, interval, 869 metric + metric_txsta, 0, sdata); 870 } 871 872 rcu_read_unlock(); 873 } 874 875 876 void mesh_rx_path_sel_frame(struct ieee80211_sub_if_data *sdata, 877 struct ieee80211_mgmt *mgmt, size_t len) 878 { 879 struct ieee802_11_elems elems; 880 size_t baselen; 881 u32 path_metric; 882 struct sta_info *sta; 883 884 /* need action_code */ 885 if (len < IEEE80211_MIN_ACTION_SIZE + 1) 886 return; 887 888 rcu_read_lock(); 889 sta = sta_info_get(sdata, mgmt->sa); 890 if (!sta || sta->mesh->plink_state != NL80211_PLINK_ESTAB) { 891 rcu_read_unlock(); 892 return; 893 } 894 rcu_read_unlock(); 895 896 baselen = (u8 *) mgmt->u.action.u.mesh_action.variable - (u8 *) mgmt; 897 ieee802_11_parse_elems(mgmt->u.action.u.mesh_action.variable, 898 len - baselen, false, &elems); 899 900 if (elems.preq) { 901 if (elems.preq_len != 37) 902 /* Right now we support just 1 destination and no AE */ 903 return; 904 path_metric = hwmp_route_info_get(sdata, mgmt, elems.preq, 905 MPATH_PREQ); 906 if (path_metric) 907 hwmp_preq_frame_process(sdata, mgmt, elems.preq, 908 path_metric); 909 } 910 if (elems.prep) { 911 if (elems.prep_len != 31) 912 /* Right now we support no AE */ 913 return; 914 path_metric = hwmp_route_info_get(sdata, mgmt, elems.prep, 915 MPATH_PREP); 916 if (path_metric) 917 hwmp_prep_frame_process(sdata, mgmt, elems.prep, 918 path_metric); 919 } 920 if (elems.perr) { 921 if (elems.perr_len != 15) 922 /* Right now we support only one destination per PERR */ 923 return; 924 hwmp_perr_frame_process(sdata, mgmt, elems.perr); 925 } 926 if (elems.rann) 927 hwmp_rann_frame_process(sdata, mgmt, elems.rann); 928 } 929 930 /** 931 * mesh_queue_preq - queue a PREQ to a given destination 932 * 933 * @mpath: mesh path to discover 934 * @flags: special attributes of the PREQ to be sent 935 * 936 * Locking: the function must be called from within a rcu read lock block. 937 * 938 */ 939 static void mesh_queue_preq(struct mesh_path *mpath, u8 flags) 940 { 941 struct ieee80211_sub_if_data *sdata = mpath->sdata; 942 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 943 struct mesh_preq_queue *preq_node; 944 945 preq_node = kmalloc(sizeof(struct mesh_preq_queue), GFP_ATOMIC); 946 if (!preq_node) { 947 mhwmp_dbg(sdata, "could not allocate PREQ node\n"); 948 return; 949 } 950 951 spin_lock_bh(&ifmsh->mesh_preq_queue_lock); 952 if (ifmsh->preq_queue_len == MAX_PREQ_QUEUE_LEN) { 953 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock); 954 kfree(preq_node); 955 if (printk_ratelimit()) 956 mhwmp_dbg(sdata, "PREQ node queue full\n"); 957 return; 958 } 959 960 spin_lock(&mpath->state_lock); 961 if (mpath->flags & MESH_PATH_REQ_QUEUED) { 962 spin_unlock(&mpath->state_lock); 963 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock); 964 kfree(preq_node); 965 return; 966 } 967 968 memcpy(preq_node->dst, mpath->dst, ETH_ALEN); 969 preq_node->flags = flags; 970 971 mpath->flags |= MESH_PATH_REQ_QUEUED; 972 spin_unlock(&mpath->state_lock); 973 974 list_add_tail(&preq_node->list, &ifmsh->preq_queue.list); 975 ++ifmsh->preq_queue_len; 976 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock); 977 978 if (time_after(jiffies, ifmsh->last_preq + min_preq_int_jiff(sdata))) 979 ieee80211_queue_work(&sdata->local->hw, &sdata->work); 980 981 else if (time_before(jiffies, ifmsh->last_preq)) { 982 /* avoid long wait if did not send preqs for a long time 983 * and jiffies wrapped around 984 */ 985 ifmsh->last_preq = jiffies - min_preq_int_jiff(sdata) - 1; 986 ieee80211_queue_work(&sdata->local->hw, &sdata->work); 987 } else 988 mod_timer(&ifmsh->mesh_path_timer, ifmsh->last_preq + 989 min_preq_int_jiff(sdata)); 990 } 991 992 /** 993 * mesh_path_start_discovery - launch a path discovery from the PREQ queue 994 * 995 * @sdata: local mesh subif 996 */ 997 void mesh_path_start_discovery(struct ieee80211_sub_if_data *sdata) 998 { 999 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 1000 struct mesh_preq_queue *preq_node; 1001 struct mesh_path *mpath; 1002 u8 ttl, target_flags = 0; 1003 const u8 *da; 1004 u32 lifetime; 1005 1006 spin_lock_bh(&ifmsh->mesh_preq_queue_lock); 1007 if (!ifmsh->preq_queue_len || 1008 time_before(jiffies, ifmsh->last_preq + 1009 min_preq_int_jiff(sdata))) { 1010 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock); 1011 return; 1012 } 1013 1014 preq_node = list_first_entry(&ifmsh->preq_queue.list, 1015 struct mesh_preq_queue, list); 1016 list_del(&preq_node->list); 1017 --ifmsh->preq_queue_len; 1018 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock); 1019 1020 rcu_read_lock(); 1021 mpath = mesh_path_lookup(sdata, preq_node->dst); 1022 if (!mpath) 1023 goto enddiscovery; 1024 1025 spin_lock_bh(&mpath->state_lock); 1026 if (mpath->flags & MESH_PATH_DELETED) { 1027 spin_unlock_bh(&mpath->state_lock); 1028 goto enddiscovery; 1029 } 1030 mpath->flags &= ~MESH_PATH_REQ_QUEUED; 1031 if (preq_node->flags & PREQ_Q_F_START) { 1032 if (mpath->flags & MESH_PATH_RESOLVING) { 1033 spin_unlock_bh(&mpath->state_lock); 1034 goto enddiscovery; 1035 } else { 1036 mpath->flags &= ~MESH_PATH_RESOLVED; 1037 mpath->flags |= MESH_PATH_RESOLVING; 1038 mpath->discovery_retries = 0; 1039 mpath->discovery_timeout = disc_timeout_jiff(sdata); 1040 } 1041 } else if (!(mpath->flags & MESH_PATH_RESOLVING) || 1042 mpath->flags & MESH_PATH_RESOLVED) { 1043 mpath->flags &= ~MESH_PATH_RESOLVING; 1044 spin_unlock_bh(&mpath->state_lock); 1045 goto enddiscovery; 1046 } 1047 1048 ifmsh->last_preq = jiffies; 1049 1050 if (time_after(jiffies, ifmsh->last_sn_update + 1051 net_traversal_jiffies(sdata)) || 1052 time_before(jiffies, ifmsh->last_sn_update)) { 1053 ++ifmsh->sn; 1054 sdata->u.mesh.last_sn_update = jiffies; 1055 } 1056 lifetime = default_lifetime(sdata); 1057 ttl = sdata->u.mesh.mshcfg.element_ttl; 1058 if (ttl == 0) { 1059 sdata->u.mesh.mshstats.dropped_frames_ttl++; 1060 spin_unlock_bh(&mpath->state_lock); 1061 goto enddiscovery; 1062 } 1063 1064 if (preq_node->flags & PREQ_Q_F_REFRESH) 1065 target_flags |= IEEE80211_PREQ_TO_FLAG; 1066 else 1067 target_flags &= ~IEEE80211_PREQ_TO_FLAG; 1068 1069 spin_unlock_bh(&mpath->state_lock); 1070 da = (mpath->is_root) ? mpath->rann_snd_addr : broadcast_addr; 1071 mesh_path_sel_frame_tx(MPATH_PREQ, 0, sdata->vif.addr, ifmsh->sn, 1072 target_flags, mpath->dst, mpath->sn, da, 0, 1073 ttl, lifetime, 0, ifmsh->preq_id++, sdata); 1074 mod_timer(&mpath->timer, jiffies + mpath->discovery_timeout); 1075 1076 enddiscovery: 1077 rcu_read_unlock(); 1078 kfree(preq_node); 1079 } 1080 1081 /** 1082 * mesh_nexthop_resolve - lookup next hop; conditionally start path discovery 1083 * 1084 * @skb: 802.11 frame to be sent 1085 * @sdata: network subif the frame will be sent through 1086 * 1087 * Lookup next hop for given skb and start path discovery if no 1088 * forwarding information is found. 1089 * 1090 * Returns: 0 if the next hop was found and -ENOENT if the frame was queued. 1091 * skb is freeed here if no mpath could be allocated. 1092 */ 1093 int mesh_nexthop_resolve(struct ieee80211_sub_if_data *sdata, 1094 struct sk_buff *skb) 1095 { 1096 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 1097 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 1098 struct mesh_path *mpath; 1099 struct sk_buff *skb_to_free = NULL; 1100 u8 *target_addr = hdr->addr3; 1101 int err = 0; 1102 1103 /* Nulls are only sent to peers for PS and should be pre-addressed */ 1104 if (ieee80211_is_qos_nullfunc(hdr->frame_control)) 1105 return 0; 1106 1107 rcu_read_lock(); 1108 err = mesh_nexthop_lookup(sdata, skb); 1109 if (!err) 1110 goto endlookup; 1111 1112 /* no nexthop found, start resolving */ 1113 mpath = mesh_path_lookup(sdata, target_addr); 1114 if (!mpath) { 1115 mpath = mesh_path_add(sdata, target_addr); 1116 if (IS_ERR(mpath)) { 1117 mesh_path_discard_frame(sdata, skb); 1118 err = PTR_ERR(mpath); 1119 goto endlookup; 1120 } 1121 } 1122 1123 if (!(mpath->flags & MESH_PATH_RESOLVING)) 1124 mesh_queue_preq(mpath, PREQ_Q_F_START); 1125 1126 if (skb_queue_len(&mpath->frame_queue) >= MESH_FRAME_QUEUE_LEN) 1127 skb_to_free = skb_dequeue(&mpath->frame_queue); 1128 1129 info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING; 1130 ieee80211_set_qos_hdr(sdata, skb); 1131 skb_queue_tail(&mpath->frame_queue, skb); 1132 err = -ENOENT; 1133 if (skb_to_free) 1134 mesh_path_discard_frame(sdata, skb_to_free); 1135 1136 endlookup: 1137 rcu_read_unlock(); 1138 return err; 1139 } 1140 1141 /** 1142 * mesh_nexthop_lookup - put the appropriate next hop on a mesh frame. Calling 1143 * this function is considered "using" the associated mpath, so preempt a path 1144 * refresh if this mpath expires soon. 1145 * 1146 * @skb: 802.11 frame to be sent 1147 * @sdata: network subif the frame will be sent through 1148 * 1149 * Returns: 0 if the next hop was found. Nonzero otherwise. 1150 */ 1151 int mesh_nexthop_lookup(struct ieee80211_sub_if_data *sdata, 1152 struct sk_buff *skb) 1153 { 1154 struct mesh_path *mpath; 1155 struct sta_info *next_hop; 1156 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 1157 u8 *target_addr = hdr->addr3; 1158 int err = -ENOENT; 1159 1160 rcu_read_lock(); 1161 mpath = mesh_path_lookup(sdata, target_addr); 1162 1163 if (!mpath || !(mpath->flags & MESH_PATH_ACTIVE)) 1164 goto endlookup; 1165 1166 if (time_after(jiffies, 1167 mpath->exp_time - 1168 msecs_to_jiffies(sdata->u.mesh.mshcfg.path_refresh_time)) && 1169 ether_addr_equal(sdata->vif.addr, hdr->addr4) && 1170 !(mpath->flags & MESH_PATH_RESOLVING) && 1171 !(mpath->flags & MESH_PATH_FIXED)) 1172 mesh_queue_preq(mpath, PREQ_Q_F_START | PREQ_Q_F_REFRESH); 1173 1174 next_hop = rcu_dereference(mpath->next_hop); 1175 if (next_hop) { 1176 memcpy(hdr->addr1, next_hop->sta.addr, ETH_ALEN); 1177 memcpy(hdr->addr2, sdata->vif.addr, ETH_ALEN); 1178 ieee80211_mps_set_frame_flags(sdata, next_hop, hdr); 1179 err = 0; 1180 } 1181 1182 endlookup: 1183 rcu_read_unlock(); 1184 return err; 1185 } 1186 1187 void mesh_path_timer(unsigned long data) 1188 { 1189 struct mesh_path *mpath = (void *) data; 1190 struct ieee80211_sub_if_data *sdata = mpath->sdata; 1191 int ret; 1192 1193 if (sdata->local->quiescing) 1194 return; 1195 1196 spin_lock_bh(&mpath->state_lock); 1197 if (mpath->flags & MESH_PATH_RESOLVED || 1198 (!(mpath->flags & MESH_PATH_RESOLVING))) { 1199 mpath->flags &= ~(MESH_PATH_RESOLVING | MESH_PATH_RESOLVED); 1200 spin_unlock_bh(&mpath->state_lock); 1201 } else if (mpath->discovery_retries < max_preq_retries(sdata)) { 1202 ++mpath->discovery_retries; 1203 mpath->discovery_timeout *= 2; 1204 mpath->flags &= ~MESH_PATH_REQ_QUEUED; 1205 spin_unlock_bh(&mpath->state_lock); 1206 mesh_queue_preq(mpath, 0); 1207 } else { 1208 mpath->flags &= ~(MESH_PATH_RESOLVING | 1209 MESH_PATH_RESOLVED | 1210 MESH_PATH_REQ_QUEUED); 1211 mpath->exp_time = jiffies; 1212 spin_unlock_bh(&mpath->state_lock); 1213 if (!mpath->is_gate && mesh_gate_num(sdata) > 0) { 1214 ret = mesh_path_send_to_gates(mpath); 1215 if (ret) 1216 mhwmp_dbg(sdata, "no gate was reachable\n"); 1217 } else 1218 mesh_path_flush_pending(mpath); 1219 } 1220 } 1221 1222 void mesh_path_tx_root_frame(struct ieee80211_sub_if_data *sdata) 1223 { 1224 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 1225 u32 interval = ifmsh->mshcfg.dot11MeshHWMPRannInterval; 1226 u8 flags, target_flags = 0; 1227 1228 flags = (ifmsh->mshcfg.dot11MeshGateAnnouncementProtocol) 1229 ? RANN_FLAG_IS_GATE : 0; 1230 1231 switch (ifmsh->mshcfg.dot11MeshHWMPRootMode) { 1232 case IEEE80211_PROACTIVE_RANN: 1233 mesh_path_sel_frame_tx(MPATH_RANN, flags, sdata->vif.addr, 1234 ++ifmsh->sn, 0, NULL, 0, broadcast_addr, 1235 0, ifmsh->mshcfg.element_ttl, 1236 interval, 0, 0, sdata); 1237 break; 1238 case IEEE80211_PROACTIVE_PREQ_WITH_PREP: 1239 flags |= IEEE80211_PREQ_PROACTIVE_PREP_FLAG; 1240 case IEEE80211_PROACTIVE_PREQ_NO_PREP: 1241 interval = ifmsh->mshcfg.dot11MeshHWMPactivePathToRootTimeout; 1242 target_flags |= IEEE80211_PREQ_TO_FLAG | 1243 IEEE80211_PREQ_USN_FLAG; 1244 mesh_path_sel_frame_tx(MPATH_PREQ, flags, sdata->vif.addr, 1245 ++ifmsh->sn, target_flags, 1246 (u8 *) broadcast_addr, 0, broadcast_addr, 1247 0, ifmsh->mshcfg.element_ttl, interval, 1248 0, ifmsh->preq_id++, sdata); 1249 break; 1250 default: 1251 mhwmp_dbg(sdata, "Proactive mechanism not supported\n"); 1252 return; 1253 } 1254 } 1255