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 #define LINK_FAIL_THRESH 95 20 21 #define MAX_PREQ_QUEUE_LEN 64 22 23 static void mesh_queue_preq(struct mesh_path *, u8); 24 25 static inline u32 u32_field_get(const u8 *preq_elem, int offset, bool ae) 26 { 27 if (ae) 28 offset += 6; 29 return get_unaligned_le32(preq_elem + offset); 30 } 31 32 static inline u16 u16_field_get(const u8 *preq_elem, int offset, bool ae) 33 { 34 if (ae) 35 offset += 6; 36 return get_unaligned_le16(preq_elem + offset); 37 } 38 39 /* HWMP IE processing macros */ 40 #define AE_F (1<<6) 41 #define AE_F_SET(x) (*x & AE_F) 42 #define PREQ_IE_FLAGS(x) (*(x)) 43 #define PREQ_IE_HOPCOUNT(x) (*(x + 1)) 44 #define PREQ_IE_TTL(x) (*(x + 2)) 45 #define PREQ_IE_PREQ_ID(x) u32_field_get(x, 3, 0) 46 #define PREQ_IE_ORIG_ADDR(x) (x + 7) 47 #define PREQ_IE_ORIG_SN(x) u32_field_get(x, 13, 0) 48 #define PREQ_IE_LIFETIME(x) u32_field_get(x, 17, AE_F_SET(x)) 49 #define PREQ_IE_METRIC(x) u32_field_get(x, 21, AE_F_SET(x)) 50 #define PREQ_IE_TARGET_F(x) (*(AE_F_SET(x) ? x + 32 : x + 26)) 51 #define PREQ_IE_TARGET_ADDR(x) (AE_F_SET(x) ? x + 33 : x + 27) 52 #define PREQ_IE_TARGET_SN(x) u32_field_get(x, 33, AE_F_SET(x)) 53 54 55 #define PREP_IE_FLAGS(x) PREQ_IE_FLAGS(x) 56 #define PREP_IE_HOPCOUNT(x) PREQ_IE_HOPCOUNT(x) 57 #define PREP_IE_TTL(x) PREQ_IE_TTL(x) 58 #define PREP_IE_ORIG_ADDR(x) (AE_F_SET(x) ? x + 27 : x + 21) 59 #define PREP_IE_ORIG_SN(x) u32_field_get(x, 27, AE_F_SET(x)) 60 #define PREP_IE_LIFETIME(x) u32_field_get(x, 13, AE_F_SET(x)) 61 #define PREP_IE_METRIC(x) u32_field_get(x, 17, AE_F_SET(x)) 62 #define PREP_IE_TARGET_ADDR(x) (x + 3) 63 #define PREP_IE_TARGET_SN(x) u32_field_get(x, 9, 0) 64 65 #define PERR_IE_TTL(x) (*(x)) 66 #define PERR_IE_TARGET_FLAGS(x) (*(x + 2)) 67 #define PERR_IE_TARGET_ADDR(x) (x + 3) 68 #define PERR_IE_TARGET_SN(x) u32_field_get(x, 9, 0) 69 #define PERR_IE_TARGET_RCODE(x) u16_field_get(x, 13, 0) 70 71 #define MSEC_TO_TU(x) (x*1000/1024) 72 #define SN_GT(x, y) ((s32)(y - x) < 0) 73 #define SN_LT(x, y) ((s32)(x - y) < 0) 74 #define MAX_SANE_SN_DELTA 32 75 76 static inline u32 SN_DELTA(u32 x, u32 y) 77 { 78 return x >= y ? x - y : y - x; 79 } 80 81 #define net_traversal_jiffies(s) \ 82 msecs_to_jiffies(s->u.mesh.mshcfg.dot11MeshHWMPnetDiameterTraversalTime) 83 #define default_lifetime(s) \ 84 MSEC_TO_TU(s->u.mesh.mshcfg.dot11MeshHWMPactivePathTimeout) 85 #define min_preq_int_jiff(s) \ 86 (msecs_to_jiffies(s->u.mesh.mshcfg.dot11MeshHWMPpreqMinInterval)) 87 #define max_preq_retries(s) (s->u.mesh.mshcfg.dot11MeshHWMPmaxPREQretries) 88 #define disc_timeout_jiff(s) \ 89 msecs_to_jiffies(sdata->u.mesh.mshcfg.min_discovery_timeout) 90 #define root_path_confirmation_jiffies(s) \ 91 msecs_to_jiffies(sdata->u.mesh.mshcfg.dot11MeshHWMPconfirmationInterval) 92 93 enum mpath_frame_type { 94 MPATH_PREQ = 0, 95 MPATH_PREP, 96 MPATH_PERR, 97 MPATH_RANN 98 }; 99 100 static const u8 broadcast_addr[ETH_ALEN] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff}; 101 102 static int mesh_path_sel_frame_tx(enum mpath_frame_type action, u8 flags, 103 const u8 *orig_addr, u32 orig_sn, 104 u8 target_flags, const u8 *target, 105 u32 target_sn, const u8 *da, 106 u8 hop_count, u8 ttl, 107 u32 lifetime, u32 metric, u32 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", orig_addr); 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 } 159 *pos++ = ie_len; 160 *pos++ = flags; 161 *pos++ = hop_count; 162 *pos++ = ttl; 163 if (action == MPATH_PREP) { 164 memcpy(pos, target, ETH_ALEN); 165 pos += ETH_ALEN; 166 put_unaligned_le32(target_sn, pos); 167 pos += 4; 168 } else { 169 if (action == MPATH_PREQ) { 170 put_unaligned_le32(preq_id, pos); 171 pos += 4; 172 } 173 memcpy(pos, orig_addr, ETH_ALEN); 174 pos += ETH_ALEN; 175 put_unaligned_le32(orig_sn, pos); 176 pos += 4; 177 } 178 put_unaligned_le32(lifetime, pos); /* interval for RANN */ 179 pos += 4; 180 put_unaligned_le32(metric, pos); 181 pos += 4; 182 if (action == MPATH_PREQ) { 183 *pos++ = 1; /* destination count */ 184 *pos++ = target_flags; 185 memcpy(pos, target, ETH_ALEN); 186 pos += ETH_ALEN; 187 put_unaligned_le32(target_sn, pos); 188 pos += 4; 189 } else if (action == MPATH_PREP) { 190 memcpy(pos, orig_addr, ETH_ALEN); 191 pos += ETH_ALEN; 192 put_unaligned_le32(orig_sn, pos); 193 pos += 4; 194 } 195 196 ieee80211_tx_skb(sdata, skb); 197 return 0; 198 } 199 200 201 /* Headroom is not adjusted. Caller should ensure that skb has sufficient 202 * headroom in case the frame is encrypted. */ 203 static void prepare_frame_for_deferred_tx(struct ieee80211_sub_if_data *sdata, 204 struct sk_buff *skb) 205 { 206 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 207 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 208 209 skb_reset_mac_header(skb); 210 skb_reset_network_header(skb); 211 skb_reset_transport_header(skb); 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 ieee80211_mps_set_frame_flags(sdata, NULL, hdr); 221 } 222 223 /** 224 * mesh_path_error_tx - Sends a PERR mesh management frame 225 * 226 * @ttl: allowed remaining hops 227 * @target: broken destination 228 * @target_sn: SN of the broken destination 229 * @target_rcode: reason code for this PERR 230 * @ra: node this frame is addressed to 231 * @sdata: local mesh subif 232 * 233 * Note: This function may be called with driver locks taken that the driver 234 * also acquires in the TX path. To avoid a deadlock we don't transmit the 235 * frame directly but add it to the pending queue instead. 236 */ 237 int mesh_path_error_tx(struct ieee80211_sub_if_data *sdata, 238 u8 ttl, const u8 *target, u32 target_sn, 239 u16 target_rcode, const u8 *ra) 240 { 241 struct ieee80211_local *local = sdata->local; 242 struct sk_buff *skb; 243 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 244 struct ieee80211_mgmt *mgmt; 245 u8 *pos, ie_len; 246 int hdr_len = offsetof(struct ieee80211_mgmt, u.action.u.mesh_action) + 247 sizeof(mgmt->u.action.u.mesh_action); 248 249 if (time_before(jiffies, ifmsh->next_perr)) 250 return -EAGAIN; 251 252 skb = dev_alloc_skb(local->tx_headroom + 253 sdata->encrypt_headroom + 254 IEEE80211_ENCRYPT_TAILROOM + 255 hdr_len + 256 2 + 15 /* PERR IE */); 257 if (!skb) 258 return -1; 259 skb_reserve(skb, local->tx_headroom + sdata->encrypt_headroom); 260 mgmt = (struct ieee80211_mgmt *) skb_put(skb, hdr_len); 261 memset(mgmt, 0, hdr_len); 262 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 263 IEEE80211_STYPE_ACTION); 264 265 memcpy(mgmt->da, ra, ETH_ALEN); 266 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN); 267 /* BSSID == SA */ 268 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN); 269 mgmt->u.action.category = WLAN_CATEGORY_MESH_ACTION; 270 mgmt->u.action.u.mesh_action.action_code = 271 WLAN_MESH_ACTION_HWMP_PATH_SELECTION; 272 ie_len = 15; 273 pos = skb_put(skb, 2 + ie_len); 274 *pos++ = WLAN_EID_PERR; 275 *pos++ = ie_len; 276 /* ttl */ 277 *pos++ = ttl; 278 /* number of destinations */ 279 *pos++ = 1; 280 /* Flags field has AE bit only as defined in 281 * sec 8.4.2.117 IEEE802.11-2012 282 */ 283 *pos = 0; 284 pos++; 285 memcpy(pos, target, ETH_ALEN); 286 pos += ETH_ALEN; 287 put_unaligned_le32(target_sn, pos); 288 pos += 4; 289 put_unaligned_le16(target_rcode, pos); 290 291 /* see note in function header */ 292 prepare_frame_for_deferred_tx(sdata, skb); 293 ifmsh->next_perr = TU_TO_EXP_TIME( 294 ifmsh->mshcfg.dot11MeshHWMPperrMinInterval); 295 ieee80211_add_pending_skb(local, skb); 296 return 0; 297 } 298 299 void ieee80211s_update_metric(struct ieee80211_local *local, 300 struct sta_info *sta, struct sk_buff *skb) 301 { 302 struct ieee80211_tx_info *txinfo = IEEE80211_SKB_CB(skb); 303 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 304 int failed; 305 306 if (!ieee80211_is_data(hdr->frame_control)) 307 return; 308 309 failed = !(txinfo->flags & IEEE80211_TX_STAT_ACK); 310 311 /* moving average, scaled to 100. 312 * feed failure as 100 and success as 0 313 */ 314 ewma_mesh_fail_avg_add(&sta->mesh->fail_avg, failed * 100); 315 if (ewma_mesh_fail_avg_read(&sta->mesh->fail_avg) > 316 LINK_FAIL_THRESH) 317 mesh_plink_broken(sta); 318 } 319 320 static u32 airtime_link_metric_get(struct ieee80211_local *local, 321 struct sta_info *sta) 322 { 323 struct rate_info rinfo; 324 /* This should be adjusted for each device */ 325 int device_constant = 1 << ARITH_SHIFT; 326 int test_frame_len = TEST_FRAME_LEN << ARITH_SHIFT; 327 int s_unit = 1 << ARITH_SHIFT; 328 int rate, err; 329 u32 tx_time, estimated_retx; 330 u64 result; 331 unsigned long fail_avg = 332 ewma_mesh_fail_avg_read(&sta->mesh->fail_avg); 333 334 /* Try to get rate based on HW/SW RC algorithm. 335 * Rate is returned in units of Kbps, correct this 336 * to comply with airtime calculation units 337 * Round up in case we get rate < 100Kbps 338 */ 339 rate = DIV_ROUND_UP(sta_get_expected_throughput(sta), 100); 340 341 if (rate) { 342 err = 0; 343 } else { 344 if (fail_avg > LINK_FAIL_THRESH) 345 return MAX_METRIC; 346 347 sta_set_rate_info_tx(sta, &sta->tx_stats.last_rate, &rinfo); 348 rate = cfg80211_calculate_bitrate(&rinfo); 349 if (WARN_ON(!rate)) 350 return MAX_METRIC; 351 352 err = (fail_avg << ARITH_SHIFT) / 100; 353 } 354 355 /* bitrate is in units of 100 Kbps, while we need rate in units of 356 * 1Mbps. This will be corrected on tx_time computation. 357 */ 358 tx_time = (device_constant + 10 * test_frame_len / rate); 359 estimated_retx = ((1 << (2 * ARITH_SHIFT)) / (s_unit - err)); 360 result = (tx_time * estimated_retx) >> (2 * ARITH_SHIFT); 361 return (u32)result; 362 } 363 364 /** 365 * hwmp_route_info_get - Update routing info to originator and transmitter 366 * 367 * @sdata: local mesh subif 368 * @mgmt: mesh management frame 369 * @hwmp_ie: hwmp information element (PREP or PREQ) 370 * @action: type of hwmp ie 371 * 372 * This function updates the path routing information to the originator and the 373 * transmitter of a HWMP PREQ or PREP frame. 374 * 375 * Returns: metric to frame originator or 0 if the frame should not be further 376 * processed 377 * 378 * Notes: this function is the only place (besides user-provided info) where 379 * path routing information is updated. 380 */ 381 static u32 hwmp_route_info_get(struct ieee80211_sub_if_data *sdata, 382 struct ieee80211_mgmt *mgmt, 383 const u8 *hwmp_ie, enum mpath_frame_type action) 384 { 385 struct ieee80211_local *local = sdata->local; 386 struct mesh_path *mpath; 387 struct sta_info *sta; 388 bool fresh_info; 389 const u8 *orig_addr, *ta; 390 u32 orig_sn, orig_metric; 391 unsigned long orig_lifetime, exp_time; 392 u32 last_hop_metric, new_metric; 393 bool process = true; 394 395 rcu_read_lock(); 396 sta = sta_info_get(sdata, mgmt->sa); 397 if (!sta) { 398 rcu_read_unlock(); 399 return 0; 400 } 401 402 last_hop_metric = airtime_link_metric_get(local, sta); 403 /* Update and check originator routing info */ 404 fresh_info = true; 405 406 switch (action) { 407 case MPATH_PREQ: 408 orig_addr = PREQ_IE_ORIG_ADDR(hwmp_ie); 409 orig_sn = PREQ_IE_ORIG_SN(hwmp_ie); 410 orig_lifetime = PREQ_IE_LIFETIME(hwmp_ie); 411 orig_metric = PREQ_IE_METRIC(hwmp_ie); 412 break; 413 case MPATH_PREP: 414 /* Originator here refers to the MP that was the target in the 415 * Path Request. We divert from the nomenclature in the draft 416 * so that we can easily use a single function to gather path 417 * information from both PREQ and PREP frames. 418 */ 419 orig_addr = PREP_IE_TARGET_ADDR(hwmp_ie); 420 orig_sn = PREP_IE_TARGET_SN(hwmp_ie); 421 orig_lifetime = PREP_IE_LIFETIME(hwmp_ie); 422 orig_metric = PREP_IE_METRIC(hwmp_ie); 423 break; 424 default: 425 rcu_read_unlock(); 426 return 0; 427 } 428 new_metric = orig_metric + last_hop_metric; 429 if (new_metric < orig_metric) 430 new_metric = MAX_METRIC; 431 exp_time = TU_TO_EXP_TIME(orig_lifetime); 432 433 if (ether_addr_equal(orig_addr, sdata->vif.addr)) { 434 /* This MP is the originator, we are not interested in this 435 * frame, except for updating transmitter's path info. 436 */ 437 process = false; 438 fresh_info = false; 439 } else { 440 mpath = mesh_path_lookup(sdata, orig_addr); 441 if (mpath) { 442 spin_lock_bh(&mpath->state_lock); 443 if (mpath->flags & MESH_PATH_FIXED) 444 fresh_info = false; 445 else if ((mpath->flags & MESH_PATH_ACTIVE) && 446 (mpath->flags & MESH_PATH_SN_VALID)) { 447 if (SN_GT(mpath->sn, orig_sn) || 448 (mpath->sn == orig_sn && 449 new_metric >= mpath->metric)) { 450 process = false; 451 fresh_info = false; 452 } 453 } else if (!(mpath->flags & MESH_PATH_ACTIVE)) { 454 bool have_sn, newer_sn, bounced; 455 456 have_sn = mpath->flags & MESH_PATH_SN_VALID; 457 newer_sn = have_sn && SN_GT(orig_sn, mpath->sn); 458 bounced = have_sn && 459 (SN_DELTA(orig_sn, mpath->sn) > 460 MAX_SANE_SN_DELTA); 461 462 if (!have_sn || newer_sn) { 463 /* if SN is newer than what we had 464 * then we can take it */; 465 } else if (bounced) { 466 /* if SN is way different than what 467 * we had then assume the other side 468 * rebooted or restarted */; 469 } else { 470 process = false; 471 fresh_info = false; 472 } 473 } 474 } else { 475 mpath = mesh_path_add(sdata, orig_addr); 476 if (IS_ERR(mpath)) { 477 rcu_read_unlock(); 478 return 0; 479 } 480 spin_lock_bh(&mpath->state_lock); 481 } 482 483 if (fresh_info) { 484 mesh_path_assign_nexthop(mpath, sta); 485 mpath->flags |= MESH_PATH_SN_VALID; 486 mpath->metric = new_metric; 487 mpath->sn = orig_sn; 488 mpath->exp_time = time_after(mpath->exp_time, exp_time) 489 ? mpath->exp_time : exp_time; 490 mesh_path_activate(mpath); 491 spin_unlock_bh(&mpath->state_lock); 492 ewma_mesh_fail_avg_init(&sta->mesh->fail_avg); 493 /* init it at a low value - 0 start is tricky */ 494 ewma_mesh_fail_avg_add(&sta->mesh->fail_avg, 1); 495 mesh_path_tx_pending(mpath); 496 /* draft says preq_id should be saved to, but there does 497 * not seem to be any use for it, skipping by now 498 */ 499 } else 500 spin_unlock_bh(&mpath->state_lock); 501 } 502 503 /* Update and check transmitter routing info */ 504 ta = mgmt->sa; 505 if (ether_addr_equal(orig_addr, ta)) 506 fresh_info = false; 507 else { 508 fresh_info = true; 509 510 mpath = mesh_path_lookup(sdata, ta); 511 if (mpath) { 512 spin_lock_bh(&mpath->state_lock); 513 if ((mpath->flags & MESH_PATH_FIXED) || 514 ((mpath->flags & MESH_PATH_ACTIVE) && 515 (last_hop_metric > mpath->metric))) 516 fresh_info = false; 517 } else { 518 mpath = mesh_path_add(sdata, ta); 519 if (IS_ERR(mpath)) { 520 rcu_read_unlock(); 521 return 0; 522 } 523 spin_lock_bh(&mpath->state_lock); 524 } 525 526 if (fresh_info) { 527 mesh_path_assign_nexthop(mpath, sta); 528 mpath->metric = last_hop_metric; 529 mpath->exp_time = time_after(mpath->exp_time, exp_time) 530 ? mpath->exp_time : exp_time; 531 mesh_path_activate(mpath); 532 spin_unlock_bh(&mpath->state_lock); 533 ewma_mesh_fail_avg_init(&sta->mesh->fail_avg); 534 /* init it at a low value - 0 start is tricky */ 535 ewma_mesh_fail_avg_add(&sta->mesh->fail_avg, 1); 536 mesh_path_tx_pending(mpath); 537 } else 538 spin_unlock_bh(&mpath->state_lock); 539 } 540 541 rcu_read_unlock(); 542 543 return process ? new_metric : 0; 544 } 545 546 static void hwmp_preq_frame_process(struct ieee80211_sub_if_data *sdata, 547 struct ieee80211_mgmt *mgmt, 548 const u8 *preq_elem, u32 orig_metric) 549 { 550 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 551 struct mesh_path *mpath = NULL; 552 const u8 *target_addr, *orig_addr; 553 const u8 *da; 554 u8 target_flags, ttl, flags; 555 u32 orig_sn, target_sn, lifetime, target_metric = 0; 556 bool reply = false; 557 bool forward = true; 558 bool root_is_gate; 559 560 /* Update target SN, if present */ 561 target_addr = PREQ_IE_TARGET_ADDR(preq_elem); 562 orig_addr = PREQ_IE_ORIG_ADDR(preq_elem); 563 target_sn = PREQ_IE_TARGET_SN(preq_elem); 564 orig_sn = PREQ_IE_ORIG_SN(preq_elem); 565 target_flags = PREQ_IE_TARGET_F(preq_elem); 566 /* Proactive PREQ gate announcements */ 567 flags = PREQ_IE_FLAGS(preq_elem); 568 root_is_gate = !!(flags & RANN_FLAG_IS_GATE); 569 570 mhwmp_dbg(sdata, "received PREQ from %pM\n", orig_addr); 571 572 if (ether_addr_equal(target_addr, sdata->vif.addr)) { 573 mhwmp_dbg(sdata, "PREQ is for us\n"); 574 forward = false; 575 reply = true; 576 target_metric = 0; 577 if (time_after(jiffies, ifmsh->last_sn_update + 578 net_traversal_jiffies(sdata)) || 579 time_before(jiffies, ifmsh->last_sn_update)) { 580 ++ifmsh->sn; 581 ifmsh->last_sn_update = jiffies; 582 } 583 target_sn = ifmsh->sn; 584 } else if (is_broadcast_ether_addr(target_addr) && 585 (target_flags & IEEE80211_PREQ_TO_FLAG)) { 586 rcu_read_lock(); 587 mpath = mesh_path_lookup(sdata, orig_addr); 588 if (mpath) { 589 if (flags & IEEE80211_PREQ_PROACTIVE_PREP_FLAG) { 590 reply = true; 591 target_addr = sdata->vif.addr; 592 target_sn = ++ifmsh->sn; 593 target_metric = 0; 594 ifmsh->last_sn_update = jiffies; 595 } 596 if (root_is_gate) 597 mesh_path_add_gate(mpath); 598 } 599 rcu_read_unlock(); 600 } else { 601 rcu_read_lock(); 602 mpath = mesh_path_lookup(sdata, target_addr); 603 if (mpath) { 604 if ((!(mpath->flags & MESH_PATH_SN_VALID)) || 605 SN_LT(mpath->sn, target_sn)) { 606 mpath->sn = target_sn; 607 mpath->flags |= MESH_PATH_SN_VALID; 608 } else if ((!(target_flags & IEEE80211_PREQ_TO_FLAG)) && 609 (mpath->flags & MESH_PATH_ACTIVE)) { 610 reply = true; 611 target_metric = mpath->metric; 612 target_sn = mpath->sn; 613 /* Case E2 of sec 13.10.9.3 IEEE 802.11-2012*/ 614 target_flags |= IEEE80211_PREQ_TO_FLAG; 615 } 616 } 617 rcu_read_unlock(); 618 } 619 620 if (reply) { 621 lifetime = PREQ_IE_LIFETIME(preq_elem); 622 ttl = ifmsh->mshcfg.element_ttl; 623 if (ttl != 0) { 624 mhwmp_dbg(sdata, "replying to the PREQ\n"); 625 mesh_path_sel_frame_tx(MPATH_PREP, 0, orig_addr, 626 orig_sn, 0, target_addr, 627 target_sn, mgmt->sa, 0, ttl, 628 lifetime, target_metric, 0, 629 sdata); 630 } else { 631 ifmsh->mshstats.dropped_frames_ttl++; 632 } 633 } 634 635 if (forward && ifmsh->mshcfg.dot11MeshForwarding) { 636 u32 preq_id; 637 u8 hopcount; 638 639 ttl = PREQ_IE_TTL(preq_elem); 640 lifetime = PREQ_IE_LIFETIME(preq_elem); 641 if (ttl <= 1) { 642 ifmsh->mshstats.dropped_frames_ttl++; 643 return; 644 } 645 mhwmp_dbg(sdata, "forwarding the PREQ from %pM\n", orig_addr); 646 --ttl; 647 preq_id = PREQ_IE_PREQ_ID(preq_elem); 648 hopcount = PREQ_IE_HOPCOUNT(preq_elem) + 1; 649 da = (mpath && mpath->is_root) ? 650 mpath->rann_snd_addr : broadcast_addr; 651 652 if (flags & IEEE80211_PREQ_PROACTIVE_PREP_FLAG) { 653 target_addr = PREQ_IE_TARGET_ADDR(preq_elem); 654 target_sn = PREQ_IE_TARGET_SN(preq_elem); 655 } 656 657 mesh_path_sel_frame_tx(MPATH_PREQ, flags, orig_addr, 658 orig_sn, target_flags, target_addr, 659 target_sn, da, hopcount, ttl, lifetime, 660 orig_metric, preq_id, sdata); 661 if (!is_multicast_ether_addr(da)) 662 ifmsh->mshstats.fwded_unicast++; 663 else 664 ifmsh->mshstats.fwded_mcast++; 665 ifmsh->mshstats.fwded_frames++; 666 } 667 } 668 669 670 static inline struct sta_info * 671 next_hop_deref_protected(struct mesh_path *mpath) 672 { 673 return rcu_dereference_protected(mpath->next_hop, 674 lockdep_is_held(&mpath->state_lock)); 675 } 676 677 678 static void hwmp_prep_frame_process(struct ieee80211_sub_if_data *sdata, 679 struct ieee80211_mgmt *mgmt, 680 const u8 *prep_elem, u32 metric) 681 { 682 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 683 struct mesh_path *mpath; 684 const u8 *target_addr, *orig_addr; 685 u8 ttl, hopcount, flags; 686 u8 next_hop[ETH_ALEN]; 687 u32 target_sn, orig_sn, lifetime; 688 689 mhwmp_dbg(sdata, "received PREP from %pM\n", 690 PREP_IE_TARGET_ADDR(prep_elem)); 691 692 orig_addr = PREP_IE_ORIG_ADDR(prep_elem); 693 if (ether_addr_equal(orig_addr, sdata->vif.addr)) 694 /* destination, no forwarding required */ 695 return; 696 697 if (!ifmsh->mshcfg.dot11MeshForwarding) 698 return; 699 700 ttl = PREP_IE_TTL(prep_elem); 701 if (ttl <= 1) { 702 sdata->u.mesh.mshstats.dropped_frames_ttl++; 703 return; 704 } 705 706 rcu_read_lock(); 707 mpath = mesh_path_lookup(sdata, orig_addr); 708 if (mpath) 709 spin_lock_bh(&mpath->state_lock); 710 else 711 goto fail; 712 if (!(mpath->flags & MESH_PATH_ACTIVE)) { 713 spin_unlock_bh(&mpath->state_lock); 714 goto fail; 715 } 716 memcpy(next_hop, next_hop_deref_protected(mpath)->sta.addr, ETH_ALEN); 717 spin_unlock_bh(&mpath->state_lock); 718 --ttl; 719 flags = PREP_IE_FLAGS(prep_elem); 720 lifetime = PREP_IE_LIFETIME(prep_elem); 721 hopcount = PREP_IE_HOPCOUNT(prep_elem) + 1; 722 target_addr = PREP_IE_TARGET_ADDR(prep_elem); 723 target_sn = PREP_IE_TARGET_SN(prep_elem); 724 orig_sn = PREP_IE_ORIG_SN(prep_elem); 725 726 mesh_path_sel_frame_tx(MPATH_PREP, flags, orig_addr, orig_sn, 0, 727 target_addr, target_sn, next_hop, hopcount, 728 ttl, lifetime, metric, 0, sdata); 729 rcu_read_unlock(); 730 731 sdata->u.mesh.mshstats.fwded_unicast++; 732 sdata->u.mesh.mshstats.fwded_frames++; 733 return; 734 735 fail: 736 rcu_read_unlock(); 737 sdata->u.mesh.mshstats.dropped_frames_no_route++; 738 } 739 740 static void hwmp_perr_frame_process(struct ieee80211_sub_if_data *sdata, 741 struct ieee80211_mgmt *mgmt, 742 const u8 *perr_elem) 743 { 744 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 745 struct mesh_path *mpath; 746 u8 ttl; 747 const u8 *ta, *target_addr; 748 u32 target_sn; 749 u16 target_rcode; 750 751 ta = mgmt->sa; 752 ttl = PERR_IE_TTL(perr_elem); 753 if (ttl <= 1) { 754 ifmsh->mshstats.dropped_frames_ttl++; 755 return; 756 } 757 ttl--; 758 target_addr = PERR_IE_TARGET_ADDR(perr_elem); 759 target_sn = PERR_IE_TARGET_SN(perr_elem); 760 target_rcode = PERR_IE_TARGET_RCODE(perr_elem); 761 762 rcu_read_lock(); 763 mpath = mesh_path_lookup(sdata, target_addr); 764 if (mpath) { 765 struct sta_info *sta; 766 767 spin_lock_bh(&mpath->state_lock); 768 sta = next_hop_deref_protected(mpath); 769 if (mpath->flags & MESH_PATH_ACTIVE && 770 ether_addr_equal(ta, sta->sta.addr) && 771 !(mpath->flags & MESH_PATH_FIXED) && 772 (!(mpath->flags & MESH_PATH_SN_VALID) || 773 SN_GT(target_sn, mpath->sn) || target_sn == 0)) { 774 mpath->flags &= ~MESH_PATH_ACTIVE; 775 if (target_sn != 0) 776 mpath->sn = target_sn; 777 else 778 mpath->sn += 1; 779 spin_unlock_bh(&mpath->state_lock); 780 if (!ifmsh->mshcfg.dot11MeshForwarding) 781 goto endperr; 782 mesh_path_error_tx(sdata, ttl, target_addr, 783 target_sn, target_rcode, 784 broadcast_addr); 785 } else 786 spin_unlock_bh(&mpath->state_lock); 787 } 788 endperr: 789 rcu_read_unlock(); 790 } 791 792 static void hwmp_rann_frame_process(struct ieee80211_sub_if_data *sdata, 793 struct ieee80211_mgmt *mgmt, 794 const struct ieee80211_rann_ie *rann) 795 { 796 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 797 struct ieee80211_local *local = sdata->local; 798 struct sta_info *sta; 799 struct mesh_path *mpath; 800 u8 ttl, flags, hopcount; 801 const u8 *orig_addr; 802 u32 orig_sn, metric, metric_txsta, interval; 803 bool root_is_gate; 804 805 ttl = rann->rann_ttl; 806 flags = rann->rann_flags; 807 root_is_gate = !!(flags & RANN_FLAG_IS_GATE); 808 orig_addr = rann->rann_addr; 809 orig_sn = le32_to_cpu(rann->rann_seq); 810 interval = le32_to_cpu(rann->rann_interval); 811 hopcount = rann->rann_hopcount; 812 hopcount++; 813 metric = le32_to_cpu(rann->rann_metric); 814 815 /* Ignore our own RANNs */ 816 if (ether_addr_equal(orig_addr, sdata->vif.addr)) 817 return; 818 819 mhwmp_dbg(sdata, 820 "received RANN from %pM via neighbour %pM (is_gate=%d)\n", 821 orig_addr, mgmt->sa, root_is_gate); 822 823 rcu_read_lock(); 824 sta = sta_info_get(sdata, mgmt->sa); 825 if (!sta) { 826 rcu_read_unlock(); 827 return; 828 } 829 830 metric_txsta = airtime_link_metric_get(local, sta); 831 832 mpath = mesh_path_lookup(sdata, orig_addr); 833 if (!mpath) { 834 mpath = mesh_path_add(sdata, orig_addr); 835 if (IS_ERR(mpath)) { 836 rcu_read_unlock(); 837 sdata->u.mesh.mshstats.dropped_frames_no_route++; 838 return; 839 } 840 } 841 842 if (!(SN_LT(mpath->sn, orig_sn)) && 843 !(mpath->sn == orig_sn && metric < mpath->rann_metric)) { 844 rcu_read_unlock(); 845 return; 846 } 847 848 if ((!(mpath->flags & (MESH_PATH_ACTIVE | MESH_PATH_RESOLVING)) || 849 (time_after(jiffies, mpath->last_preq_to_root + 850 root_path_confirmation_jiffies(sdata)) || 851 time_before(jiffies, mpath->last_preq_to_root))) && 852 !(mpath->flags & MESH_PATH_FIXED) && (ttl != 0)) { 853 mhwmp_dbg(sdata, 854 "time to refresh root mpath %pM\n", 855 orig_addr); 856 mesh_queue_preq(mpath, PREQ_Q_F_START | PREQ_Q_F_REFRESH); 857 mpath->last_preq_to_root = jiffies; 858 } 859 860 mpath->sn = orig_sn; 861 mpath->rann_metric = metric + metric_txsta; 862 mpath->is_root = true; 863 /* Recording RANNs sender address to send individually 864 * addressed PREQs destined for root mesh STA */ 865 memcpy(mpath->rann_snd_addr, mgmt->sa, ETH_ALEN); 866 867 if (root_is_gate) 868 mesh_path_add_gate(mpath); 869 870 if (ttl <= 1) { 871 ifmsh->mshstats.dropped_frames_ttl++; 872 rcu_read_unlock(); 873 return; 874 } 875 ttl--; 876 877 if (ifmsh->mshcfg.dot11MeshForwarding) { 878 mesh_path_sel_frame_tx(MPATH_RANN, flags, orig_addr, 879 orig_sn, 0, NULL, 0, broadcast_addr, 880 hopcount, ttl, interval, 881 metric + metric_txsta, 0, sdata); 882 } 883 884 rcu_read_unlock(); 885 } 886 887 888 void mesh_rx_path_sel_frame(struct ieee80211_sub_if_data *sdata, 889 struct ieee80211_mgmt *mgmt, size_t len) 890 { 891 struct ieee802_11_elems elems; 892 size_t baselen; 893 u32 path_metric; 894 struct sta_info *sta; 895 896 /* need action_code */ 897 if (len < IEEE80211_MIN_ACTION_SIZE + 1) 898 return; 899 900 rcu_read_lock(); 901 sta = sta_info_get(sdata, mgmt->sa); 902 if (!sta || sta->mesh->plink_state != NL80211_PLINK_ESTAB) { 903 rcu_read_unlock(); 904 return; 905 } 906 rcu_read_unlock(); 907 908 baselen = (u8 *) mgmt->u.action.u.mesh_action.variable - (u8 *) mgmt; 909 ieee802_11_parse_elems(mgmt->u.action.u.mesh_action.variable, 910 len - baselen, false, &elems); 911 912 if (elems.preq) { 913 if (elems.preq_len != 37) 914 /* Right now we support just 1 destination and no AE */ 915 return; 916 path_metric = hwmp_route_info_get(sdata, mgmt, elems.preq, 917 MPATH_PREQ); 918 if (path_metric) 919 hwmp_preq_frame_process(sdata, mgmt, elems.preq, 920 path_metric); 921 } 922 if (elems.prep) { 923 if (elems.prep_len != 31) 924 /* Right now we support no AE */ 925 return; 926 path_metric = hwmp_route_info_get(sdata, mgmt, elems.prep, 927 MPATH_PREP); 928 if (path_metric) 929 hwmp_prep_frame_process(sdata, mgmt, elems.prep, 930 path_metric); 931 } 932 if (elems.perr) { 933 if (elems.perr_len != 15) 934 /* Right now we support only one destination per PERR */ 935 return; 936 hwmp_perr_frame_process(sdata, mgmt, elems.perr); 937 } 938 if (elems.rann) 939 hwmp_rann_frame_process(sdata, mgmt, elems.rann); 940 } 941 942 /** 943 * mesh_queue_preq - queue a PREQ to a given destination 944 * 945 * @mpath: mesh path to discover 946 * @flags: special attributes of the PREQ to be sent 947 * 948 * Locking: the function must be called from within a rcu read lock block. 949 * 950 */ 951 static void mesh_queue_preq(struct mesh_path *mpath, u8 flags) 952 { 953 struct ieee80211_sub_if_data *sdata = mpath->sdata; 954 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 955 struct mesh_preq_queue *preq_node; 956 957 preq_node = kmalloc(sizeof(struct mesh_preq_queue), GFP_ATOMIC); 958 if (!preq_node) { 959 mhwmp_dbg(sdata, "could not allocate PREQ node\n"); 960 return; 961 } 962 963 spin_lock_bh(&ifmsh->mesh_preq_queue_lock); 964 if (ifmsh->preq_queue_len == MAX_PREQ_QUEUE_LEN) { 965 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock); 966 kfree(preq_node); 967 if (printk_ratelimit()) 968 mhwmp_dbg(sdata, "PREQ node queue full\n"); 969 return; 970 } 971 972 spin_lock(&mpath->state_lock); 973 if (mpath->flags & MESH_PATH_REQ_QUEUED) { 974 spin_unlock(&mpath->state_lock); 975 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock); 976 kfree(preq_node); 977 return; 978 } 979 980 memcpy(preq_node->dst, mpath->dst, ETH_ALEN); 981 preq_node->flags = flags; 982 983 mpath->flags |= MESH_PATH_REQ_QUEUED; 984 spin_unlock(&mpath->state_lock); 985 986 list_add_tail(&preq_node->list, &ifmsh->preq_queue.list); 987 ++ifmsh->preq_queue_len; 988 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock); 989 990 if (time_after(jiffies, ifmsh->last_preq + min_preq_int_jiff(sdata))) 991 ieee80211_queue_work(&sdata->local->hw, &sdata->work); 992 993 else if (time_before(jiffies, ifmsh->last_preq)) { 994 /* avoid long wait if did not send preqs for a long time 995 * and jiffies wrapped around 996 */ 997 ifmsh->last_preq = jiffies - min_preq_int_jiff(sdata) - 1; 998 ieee80211_queue_work(&sdata->local->hw, &sdata->work); 999 } else 1000 mod_timer(&ifmsh->mesh_path_timer, ifmsh->last_preq + 1001 min_preq_int_jiff(sdata)); 1002 } 1003 1004 /** 1005 * mesh_path_start_discovery - launch a path discovery from the PREQ queue 1006 * 1007 * @sdata: local mesh subif 1008 */ 1009 void mesh_path_start_discovery(struct ieee80211_sub_if_data *sdata) 1010 { 1011 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 1012 struct mesh_preq_queue *preq_node; 1013 struct mesh_path *mpath; 1014 u8 ttl, target_flags = 0; 1015 const u8 *da; 1016 u32 lifetime; 1017 1018 spin_lock_bh(&ifmsh->mesh_preq_queue_lock); 1019 if (!ifmsh->preq_queue_len || 1020 time_before(jiffies, ifmsh->last_preq + 1021 min_preq_int_jiff(sdata))) { 1022 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock); 1023 return; 1024 } 1025 1026 preq_node = list_first_entry(&ifmsh->preq_queue.list, 1027 struct mesh_preq_queue, list); 1028 list_del(&preq_node->list); 1029 --ifmsh->preq_queue_len; 1030 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock); 1031 1032 rcu_read_lock(); 1033 mpath = mesh_path_lookup(sdata, preq_node->dst); 1034 if (!mpath) 1035 goto enddiscovery; 1036 1037 spin_lock_bh(&mpath->state_lock); 1038 if (mpath->flags & (MESH_PATH_DELETED | MESH_PATH_FIXED)) { 1039 spin_unlock_bh(&mpath->state_lock); 1040 goto enddiscovery; 1041 } 1042 mpath->flags &= ~MESH_PATH_REQ_QUEUED; 1043 if (preq_node->flags & PREQ_Q_F_START) { 1044 if (mpath->flags & MESH_PATH_RESOLVING) { 1045 spin_unlock_bh(&mpath->state_lock); 1046 goto enddiscovery; 1047 } else { 1048 mpath->flags &= ~MESH_PATH_RESOLVED; 1049 mpath->flags |= MESH_PATH_RESOLVING; 1050 mpath->discovery_retries = 0; 1051 mpath->discovery_timeout = disc_timeout_jiff(sdata); 1052 } 1053 } else if (!(mpath->flags & MESH_PATH_RESOLVING) || 1054 mpath->flags & MESH_PATH_RESOLVED) { 1055 mpath->flags &= ~MESH_PATH_RESOLVING; 1056 spin_unlock_bh(&mpath->state_lock); 1057 goto enddiscovery; 1058 } 1059 1060 ifmsh->last_preq = jiffies; 1061 1062 if (time_after(jiffies, ifmsh->last_sn_update + 1063 net_traversal_jiffies(sdata)) || 1064 time_before(jiffies, ifmsh->last_sn_update)) { 1065 ++ifmsh->sn; 1066 sdata->u.mesh.last_sn_update = jiffies; 1067 } 1068 lifetime = default_lifetime(sdata); 1069 ttl = sdata->u.mesh.mshcfg.element_ttl; 1070 if (ttl == 0) { 1071 sdata->u.mesh.mshstats.dropped_frames_ttl++; 1072 spin_unlock_bh(&mpath->state_lock); 1073 goto enddiscovery; 1074 } 1075 1076 if (preq_node->flags & PREQ_Q_F_REFRESH) 1077 target_flags |= IEEE80211_PREQ_TO_FLAG; 1078 else 1079 target_flags &= ~IEEE80211_PREQ_TO_FLAG; 1080 1081 spin_unlock_bh(&mpath->state_lock); 1082 da = (mpath->is_root) ? mpath->rann_snd_addr : broadcast_addr; 1083 mesh_path_sel_frame_tx(MPATH_PREQ, 0, sdata->vif.addr, ifmsh->sn, 1084 target_flags, mpath->dst, mpath->sn, da, 0, 1085 ttl, lifetime, 0, ifmsh->preq_id++, sdata); 1086 mod_timer(&mpath->timer, jiffies + mpath->discovery_timeout); 1087 1088 enddiscovery: 1089 rcu_read_unlock(); 1090 kfree(preq_node); 1091 } 1092 1093 /** 1094 * mesh_nexthop_resolve - lookup next hop; conditionally start path discovery 1095 * 1096 * @skb: 802.11 frame to be sent 1097 * @sdata: network subif the frame will be sent through 1098 * 1099 * Lookup next hop for given skb and start path discovery if no 1100 * forwarding information is found. 1101 * 1102 * Returns: 0 if the next hop was found and -ENOENT if the frame was queued. 1103 * skb is freeed here if no mpath could be allocated. 1104 */ 1105 int mesh_nexthop_resolve(struct ieee80211_sub_if_data *sdata, 1106 struct sk_buff *skb) 1107 { 1108 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 1109 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 1110 struct mesh_path *mpath; 1111 struct sk_buff *skb_to_free = NULL; 1112 u8 *target_addr = hdr->addr3; 1113 int err = 0; 1114 1115 /* Nulls are only sent to peers for PS and should be pre-addressed */ 1116 if (ieee80211_is_qos_nullfunc(hdr->frame_control)) 1117 return 0; 1118 1119 rcu_read_lock(); 1120 err = mesh_nexthop_lookup(sdata, skb); 1121 if (!err) 1122 goto endlookup; 1123 1124 /* no nexthop found, start resolving */ 1125 mpath = mesh_path_lookup(sdata, target_addr); 1126 if (!mpath) { 1127 mpath = mesh_path_add(sdata, target_addr); 1128 if (IS_ERR(mpath)) { 1129 mesh_path_discard_frame(sdata, skb); 1130 err = PTR_ERR(mpath); 1131 goto endlookup; 1132 } 1133 } 1134 1135 if (!(mpath->flags & MESH_PATH_RESOLVING)) 1136 mesh_queue_preq(mpath, PREQ_Q_F_START); 1137 1138 if (skb_queue_len(&mpath->frame_queue) >= MESH_FRAME_QUEUE_LEN) 1139 skb_to_free = skb_dequeue(&mpath->frame_queue); 1140 1141 info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING; 1142 ieee80211_set_qos_hdr(sdata, skb); 1143 skb_queue_tail(&mpath->frame_queue, skb); 1144 err = -ENOENT; 1145 if (skb_to_free) 1146 mesh_path_discard_frame(sdata, skb_to_free); 1147 1148 endlookup: 1149 rcu_read_unlock(); 1150 return err; 1151 } 1152 1153 /** 1154 * mesh_nexthop_lookup - put the appropriate next hop on a mesh frame. Calling 1155 * this function is considered "using" the associated mpath, so preempt a path 1156 * refresh if this mpath expires soon. 1157 * 1158 * @skb: 802.11 frame to be sent 1159 * @sdata: network subif the frame will be sent through 1160 * 1161 * Returns: 0 if the next hop was found. Nonzero otherwise. 1162 */ 1163 int mesh_nexthop_lookup(struct ieee80211_sub_if_data *sdata, 1164 struct sk_buff *skb) 1165 { 1166 struct mesh_path *mpath; 1167 struct sta_info *next_hop; 1168 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 1169 u8 *target_addr = hdr->addr3; 1170 int err = -ENOENT; 1171 1172 rcu_read_lock(); 1173 mpath = mesh_path_lookup(sdata, target_addr); 1174 1175 if (!mpath || !(mpath->flags & MESH_PATH_ACTIVE)) 1176 goto endlookup; 1177 1178 if (time_after(jiffies, 1179 mpath->exp_time - 1180 msecs_to_jiffies(sdata->u.mesh.mshcfg.path_refresh_time)) && 1181 ether_addr_equal(sdata->vif.addr, hdr->addr4) && 1182 !(mpath->flags & MESH_PATH_RESOLVING) && 1183 !(mpath->flags & MESH_PATH_FIXED)) 1184 mesh_queue_preq(mpath, PREQ_Q_F_START | PREQ_Q_F_REFRESH); 1185 1186 next_hop = rcu_dereference(mpath->next_hop); 1187 if (next_hop) { 1188 memcpy(hdr->addr1, next_hop->sta.addr, ETH_ALEN); 1189 memcpy(hdr->addr2, sdata->vif.addr, ETH_ALEN); 1190 ieee80211_mps_set_frame_flags(sdata, next_hop, hdr); 1191 err = 0; 1192 } 1193 1194 endlookup: 1195 rcu_read_unlock(); 1196 return err; 1197 } 1198 1199 void mesh_path_timer(unsigned long data) 1200 { 1201 struct mesh_path *mpath = (void *) data; 1202 struct ieee80211_sub_if_data *sdata = mpath->sdata; 1203 int ret; 1204 1205 if (sdata->local->quiescing) 1206 return; 1207 1208 spin_lock_bh(&mpath->state_lock); 1209 if (mpath->flags & MESH_PATH_RESOLVED || 1210 (!(mpath->flags & MESH_PATH_RESOLVING))) { 1211 mpath->flags &= ~(MESH_PATH_RESOLVING | MESH_PATH_RESOLVED); 1212 spin_unlock_bh(&mpath->state_lock); 1213 } else if (mpath->discovery_retries < max_preq_retries(sdata)) { 1214 ++mpath->discovery_retries; 1215 mpath->discovery_timeout *= 2; 1216 mpath->flags &= ~MESH_PATH_REQ_QUEUED; 1217 spin_unlock_bh(&mpath->state_lock); 1218 mesh_queue_preq(mpath, 0); 1219 } else { 1220 mpath->flags &= ~(MESH_PATH_RESOLVING | 1221 MESH_PATH_RESOLVED | 1222 MESH_PATH_REQ_QUEUED); 1223 mpath->exp_time = jiffies; 1224 spin_unlock_bh(&mpath->state_lock); 1225 if (!mpath->is_gate && mesh_gate_num(sdata) > 0) { 1226 ret = mesh_path_send_to_gates(mpath); 1227 if (ret) 1228 mhwmp_dbg(sdata, "no gate was reachable\n"); 1229 } else 1230 mesh_path_flush_pending(mpath); 1231 } 1232 } 1233 1234 void mesh_path_tx_root_frame(struct ieee80211_sub_if_data *sdata) 1235 { 1236 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 1237 u32 interval = ifmsh->mshcfg.dot11MeshHWMPRannInterval; 1238 u8 flags, target_flags = 0; 1239 1240 flags = (ifmsh->mshcfg.dot11MeshGateAnnouncementProtocol) 1241 ? RANN_FLAG_IS_GATE : 0; 1242 1243 switch (ifmsh->mshcfg.dot11MeshHWMPRootMode) { 1244 case IEEE80211_PROACTIVE_RANN: 1245 mesh_path_sel_frame_tx(MPATH_RANN, flags, sdata->vif.addr, 1246 ++ifmsh->sn, 0, NULL, 0, broadcast_addr, 1247 0, ifmsh->mshcfg.element_ttl, 1248 interval, 0, 0, sdata); 1249 break; 1250 case IEEE80211_PROACTIVE_PREQ_WITH_PREP: 1251 flags |= IEEE80211_PREQ_PROACTIVE_PREP_FLAG; 1252 case IEEE80211_PROACTIVE_PREQ_NO_PREP: 1253 interval = ifmsh->mshcfg.dot11MeshHWMPactivePathToRootTimeout; 1254 target_flags |= IEEE80211_PREQ_TO_FLAG | 1255 IEEE80211_PREQ_USN_FLAG; 1256 mesh_path_sel_frame_tx(MPATH_PREQ, flags, sdata->vif.addr, 1257 ++ifmsh->sn, target_flags, 1258 (u8 *) broadcast_addr, 0, broadcast_addr, 1259 0, ifmsh->mshcfg.element_ttl, interval, 1260 0, ifmsh->preq_id++, sdata); 1261 break; 1262 default: 1263 mhwmp_dbg(sdata, "Proactive mechanism not supported\n"); 1264 return; 1265 } 1266 } 1267