1 /* 2 * Copyright (c) 2008, 2009 open80211s Ltd. 3 * Author: Luis Carlos Cobo <luisca@cozybit.com> 4 * 5 * This program is free software; you can redistribute it and/or modify 6 * it under the terms of the GNU General Public License version 2 as 7 * published by the Free Software Foundation. 8 */ 9 10 #include <linux/slab.h> 11 #include <linux/etherdevice.h> 12 #include <asm/unaligned.h> 13 #include "wme.h" 14 #include "mesh.h" 15 16 #define TEST_FRAME_LEN 8192 17 #define MAX_METRIC 0xffffffff 18 #define ARITH_SHIFT 8 19 20 #define MAX_PREQ_QUEUE_LEN 64 21 22 /* Destination only */ 23 #define MP_F_DO 0x1 24 /* Reply and forward */ 25 #define MP_F_RF 0x2 26 /* Unknown Sequence Number */ 27 #define MP_F_USN 0x01 28 /* Reason code Present */ 29 #define MP_F_RCODE 0x02 30 31 static void mesh_queue_preq(struct mesh_path *, u8); 32 33 static inline u32 u32_field_get(const u8 *preq_elem, int offset, bool ae) 34 { 35 if (ae) 36 offset += 6; 37 return get_unaligned_le32(preq_elem + offset); 38 } 39 40 static inline u32 u16_field_get(const u8 *preq_elem, int offset, bool ae) 41 { 42 if (ae) 43 offset += 6; 44 return get_unaligned_le16(preq_elem + offset); 45 } 46 47 /* HWMP IE processing macros */ 48 #define AE_F (1<<6) 49 #define AE_F_SET(x) (*x & AE_F) 50 #define PREQ_IE_FLAGS(x) (*(x)) 51 #define PREQ_IE_HOPCOUNT(x) (*(x + 1)) 52 #define PREQ_IE_TTL(x) (*(x + 2)) 53 #define PREQ_IE_PREQ_ID(x) u32_field_get(x, 3, 0) 54 #define PREQ_IE_ORIG_ADDR(x) (x + 7) 55 #define PREQ_IE_ORIG_SN(x) u32_field_get(x, 13, 0) 56 #define PREQ_IE_LIFETIME(x) u32_field_get(x, 17, AE_F_SET(x)) 57 #define PREQ_IE_METRIC(x) u32_field_get(x, 21, AE_F_SET(x)) 58 #define PREQ_IE_TARGET_F(x) (*(AE_F_SET(x) ? x + 32 : x + 26)) 59 #define PREQ_IE_TARGET_ADDR(x) (AE_F_SET(x) ? x + 33 : x + 27) 60 #define PREQ_IE_TARGET_SN(x) u32_field_get(x, 33, AE_F_SET(x)) 61 62 63 #define PREP_IE_FLAGS(x) PREQ_IE_FLAGS(x) 64 #define PREP_IE_HOPCOUNT(x) PREQ_IE_HOPCOUNT(x) 65 #define PREP_IE_TTL(x) PREQ_IE_TTL(x) 66 #define PREP_IE_ORIG_ADDR(x) (AE_F_SET(x) ? x + 27 : x + 21) 67 #define PREP_IE_ORIG_SN(x) u32_field_get(x, 27, AE_F_SET(x)) 68 #define PREP_IE_LIFETIME(x) u32_field_get(x, 13, AE_F_SET(x)) 69 #define PREP_IE_METRIC(x) u32_field_get(x, 17, AE_F_SET(x)) 70 #define PREP_IE_TARGET_ADDR(x) (x + 3) 71 #define PREP_IE_TARGET_SN(x) u32_field_get(x, 9, 0) 72 73 #define PERR_IE_TTL(x) (*(x)) 74 #define PERR_IE_TARGET_FLAGS(x) (*(x + 2)) 75 #define PERR_IE_TARGET_ADDR(x) (x + 3) 76 #define PERR_IE_TARGET_SN(x) u32_field_get(x, 9, 0) 77 #define PERR_IE_TARGET_RCODE(x) u16_field_get(x, 13, 0) 78 79 #define MSEC_TO_TU(x) (x*1000/1024) 80 #define SN_GT(x, y) ((s32)(y - x) < 0) 81 #define SN_LT(x, y) ((s32)(x - y) < 0) 82 83 #define net_traversal_jiffies(s) \ 84 msecs_to_jiffies(s->u.mesh.mshcfg.dot11MeshHWMPnetDiameterTraversalTime) 85 #define default_lifetime(s) \ 86 MSEC_TO_TU(s->u.mesh.mshcfg.dot11MeshHWMPactivePathTimeout) 87 #define min_preq_int_jiff(s) \ 88 (msecs_to_jiffies(s->u.mesh.mshcfg.dot11MeshHWMPpreqMinInterval)) 89 #define max_preq_retries(s) (s->u.mesh.mshcfg.dot11MeshHWMPmaxPREQretries) 90 #define disc_timeout_jiff(s) \ 91 msecs_to_jiffies(sdata->u.mesh.mshcfg.min_discovery_timeout) 92 #define root_path_confirmation_jiffies(s) \ 93 msecs_to_jiffies(sdata->u.mesh.mshcfg.dot11MeshHWMPconfirmationInterval) 94 95 enum mpath_frame_type { 96 MPATH_PREQ = 0, 97 MPATH_PREP, 98 MPATH_PERR, 99 MPATH_RANN 100 }; 101 102 static const u8 broadcast_addr[ETH_ALEN] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff}; 103 104 static int mesh_path_sel_frame_tx(enum mpath_frame_type action, u8 flags, 105 const u8 *orig_addr, __le32 orig_sn, 106 u8 target_flags, const u8 *target, 107 __le32 target_sn, const u8 *da, 108 u8 hop_count, u8 ttl, 109 __le32 lifetime, __le32 metric, 110 __le32 preq_id, 111 struct ieee80211_sub_if_data *sdata) 112 { 113 struct ieee80211_local *local = sdata->local; 114 struct sk_buff *skb; 115 struct ieee80211_mgmt *mgmt; 116 u8 *pos, ie_len; 117 int hdr_len = offsetof(struct ieee80211_mgmt, u.action.u.mesh_action) + 118 sizeof(mgmt->u.action.u.mesh_action); 119 120 skb = dev_alloc_skb(local->tx_headroom + 121 hdr_len + 122 2 + 37); /* max HWMP IE */ 123 if (!skb) 124 return -1; 125 skb_reserve(skb, local->tx_headroom); 126 mgmt = (struct ieee80211_mgmt *) skb_put(skb, hdr_len); 127 memset(mgmt, 0, hdr_len); 128 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 129 IEEE80211_STYPE_ACTION); 130 131 memcpy(mgmt->da, da, ETH_ALEN); 132 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN); 133 /* BSSID == SA */ 134 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN); 135 mgmt->u.action.category = WLAN_CATEGORY_MESH_ACTION; 136 mgmt->u.action.u.mesh_action.action_code = 137 WLAN_MESH_ACTION_HWMP_PATH_SELECTION; 138 139 switch (action) { 140 case MPATH_PREQ: 141 mhwmp_dbg(sdata, "sending PREQ to %pM\n", target); 142 ie_len = 37; 143 pos = skb_put(skb, 2 + ie_len); 144 *pos++ = WLAN_EID_PREQ; 145 break; 146 case MPATH_PREP: 147 mhwmp_dbg(sdata, "sending PREP to %pM\n", target); 148 ie_len = 31; 149 pos = skb_put(skb, 2 + ie_len); 150 *pos++ = WLAN_EID_PREP; 151 break; 152 case MPATH_RANN: 153 mhwmp_dbg(sdata, "sending RANN from %pM\n", orig_addr); 154 ie_len = sizeof(struct ieee80211_rann_ie); 155 pos = skb_put(skb, 2 + ie_len); 156 *pos++ = WLAN_EID_RANN; 157 break; 158 default: 159 kfree_skb(skb); 160 return -ENOTSUPP; 161 break; 162 } 163 *pos++ = ie_len; 164 *pos++ = flags; 165 *pos++ = hop_count; 166 *pos++ = ttl; 167 if (action == MPATH_PREP) { 168 memcpy(pos, target, ETH_ALEN); 169 pos += ETH_ALEN; 170 memcpy(pos, &target_sn, 4); 171 pos += 4; 172 } else { 173 if (action == MPATH_PREQ) { 174 memcpy(pos, &preq_id, 4); 175 pos += 4; 176 } 177 memcpy(pos, orig_addr, ETH_ALEN); 178 pos += ETH_ALEN; 179 memcpy(pos, &orig_sn, 4); 180 pos += 4; 181 } 182 memcpy(pos, &lifetime, 4); /* interval for RANN */ 183 pos += 4; 184 memcpy(pos, &metric, 4); 185 pos += 4; 186 if (action == MPATH_PREQ) { 187 *pos++ = 1; /* destination count */ 188 *pos++ = target_flags; 189 memcpy(pos, target, ETH_ALEN); 190 pos += ETH_ALEN; 191 memcpy(pos, &target_sn, 4); 192 pos += 4; 193 } else if (action == MPATH_PREP) { 194 memcpy(pos, orig_addr, ETH_ALEN); 195 pos += ETH_ALEN; 196 memcpy(pos, &orig_sn, 4); 197 pos += 4; 198 } 199 200 ieee80211_tx_skb(sdata, skb); 201 return 0; 202 } 203 204 205 /* Headroom is not adjusted. Caller should ensure that skb has sufficient 206 * headroom in case the frame is encrypted. */ 207 static void prepare_frame_for_deferred_tx(struct ieee80211_sub_if_data *sdata, 208 struct sk_buff *skb) 209 { 210 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 211 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 212 213 skb_set_mac_header(skb, 0); 214 skb_set_network_header(skb, 0); 215 skb_set_transport_header(skb, 0); 216 217 /* Send all internal mgmt frames on VO. Accordingly set TID to 7. */ 218 skb_set_queue_mapping(skb, IEEE80211_AC_VO); 219 skb->priority = 7; 220 221 info->control.vif = &sdata->vif; 222 info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING; 223 ieee80211_set_qos_hdr(sdata, skb); 224 ieee80211_mps_set_frame_flags(sdata, NULL, hdr); 225 } 226 227 /** 228 * mesh_path_error_tx - Sends a PERR mesh management frame 229 * 230 * @ttl: allowed remaining hops 231 * @target: broken destination 232 * @target_sn: SN of the broken destination 233 * @target_rcode: reason code for this PERR 234 * @ra: node this frame is addressed to 235 * @sdata: local mesh subif 236 * 237 * Note: This function may be called with driver locks taken that the driver 238 * also acquires in the TX path. To avoid a deadlock we don't transmit the 239 * frame directly but add it to the pending queue instead. 240 */ 241 int mesh_path_error_tx(struct ieee80211_sub_if_data *sdata, 242 u8 ttl, const u8 *target, __le32 target_sn, 243 __le16 target_rcode, const u8 *ra) 244 { 245 struct ieee80211_local *local = sdata->local; 246 struct sk_buff *skb; 247 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 248 struct ieee80211_mgmt *mgmt; 249 u8 *pos, ie_len; 250 int hdr_len = offsetof(struct ieee80211_mgmt, u.action.u.mesh_action) + 251 sizeof(mgmt->u.action.u.mesh_action); 252 253 if (time_before(jiffies, ifmsh->next_perr)) 254 return -EAGAIN; 255 256 skb = dev_alloc_skb(local->tx_headroom + 257 IEEE80211_ENCRYPT_HEADROOM + 258 IEEE80211_ENCRYPT_TAILROOM + 259 hdr_len + 260 2 + 15 /* PERR IE */); 261 if (!skb) 262 return -1; 263 skb_reserve(skb, local->tx_headroom + IEEE80211_ENCRYPT_HEADROOM); 264 mgmt = (struct ieee80211_mgmt *) skb_put(skb, hdr_len); 265 memset(mgmt, 0, hdr_len); 266 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 267 IEEE80211_STYPE_ACTION); 268 269 memcpy(mgmt->da, ra, ETH_ALEN); 270 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN); 271 /* BSSID == SA */ 272 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN); 273 mgmt->u.action.category = WLAN_CATEGORY_MESH_ACTION; 274 mgmt->u.action.u.mesh_action.action_code = 275 WLAN_MESH_ACTION_HWMP_PATH_SELECTION; 276 ie_len = 15; 277 pos = skb_put(skb, 2 + ie_len); 278 *pos++ = WLAN_EID_PERR; 279 *pos++ = ie_len; 280 /* ttl */ 281 *pos++ = ttl; 282 /* number of destinations */ 283 *pos++ = 1; 284 /* 285 * flags bit, bit 1 is unset if we know the sequence number and 286 * bit 2 is set if we have a reason code 287 */ 288 *pos = 0; 289 if (!target_sn) 290 *pos |= MP_F_USN; 291 if (target_rcode) 292 *pos |= MP_F_RCODE; 293 pos++; 294 memcpy(pos, target, ETH_ALEN); 295 pos += ETH_ALEN; 296 memcpy(pos, &target_sn, 4); 297 pos += 4; 298 memcpy(pos, &target_rcode, 2); 299 300 /* see note in function header */ 301 prepare_frame_for_deferred_tx(sdata, skb); 302 ifmsh->next_perr = TU_TO_EXP_TIME( 303 ifmsh->mshcfg.dot11MeshHWMPperrMinInterval); 304 ieee80211_add_pending_skb(local, skb); 305 return 0; 306 } 307 308 void ieee80211s_update_metric(struct ieee80211_local *local, 309 struct sta_info *sta, struct sk_buff *skb) 310 { 311 struct ieee80211_tx_info *txinfo = IEEE80211_SKB_CB(skb); 312 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 313 int failed; 314 315 if (!ieee80211_is_data(hdr->frame_control)) 316 return; 317 318 failed = !(txinfo->flags & IEEE80211_TX_STAT_ACK); 319 320 /* moving average, scaled to 100 */ 321 sta->fail_avg = ((80 * sta->fail_avg + 5) / 100 + 20 * failed); 322 if (sta->fail_avg > 95) 323 mesh_plink_broken(sta); 324 } 325 326 static u32 airtime_link_metric_get(struct ieee80211_local *local, 327 struct sta_info *sta) 328 { 329 struct rate_info rinfo; 330 /* This should be adjusted for each device */ 331 int device_constant = 1 << ARITH_SHIFT; 332 int test_frame_len = TEST_FRAME_LEN << ARITH_SHIFT; 333 int s_unit = 1 << ARITH_SHIFT; 334 int rate, err; 335 u32 tx_time, estimated_retx; 336 u64 result; 337 338 if (sta->fail_avg >= 100) 339 return MAX_METRIC; 340 341 sta_set_rate_info_tx(sta, &sta->last_tx_rate, &rinfo); 342 rate = cfg80211_calculate_bitrate(&rinfo); 343 if (WARN_ON(!rate)) 344 return MAX_METRIC; 345 346 err = (sta->fail_avg << ARITH_SHIFT) / 100; 347 348 /* bitrate is in units of 100 Kbps, while we need rate in units of 349 * 1Mbps. This will be corrected on tx_time computation. 350 */ 351 tx_time = (device_constant + 10 * test_frame_len / rate); 352 estimated_retx = ((1 << (2 * ARITH_SHIFT)) / (s_unit - err)); 353 result = (tx_time * estimated_retx) >> (2 * ARITH_SHIFT) ; 354 return (u32)result; 355 } 356 357 /** 358 * hwmp_route_info_get - Update routing info to originator and transmitter 359 * 360 * @sdata: local mesh subif 361 * @mgmt: mesh management frame 362 * @hwmp_ie: hwmp information element (PREP or PREQ) 363 * @action: type of hwmp ie 364 * 365 * This function updates the path routing information to the originator and the 366 * transmitter of a HWMP PREQ or PREP frame. 367 * 368 * Returns: metric to frame originator or 0 if the frame should not be further 369 * processed 370 * 371 * Notes: this function is the only place (besides user-provided info) where 372 * path routing information is updated. 373 */ 374 static u32 hwmp_route_info_get(struct ieee80211_sub_if_data *sdata, 375 struct ieee80211_mgmt *mgmt, 376 const u8 *hwmp_ie, enum mpath_frame_type action) 377 { 378 struct ieee80211_local *local = sdata->local; 379 struct mesh_path *mpath; 380 struct sta_info *sta; 381 bool fresh_info; 382 const u8 *orig_addr, *ta; 383 u32 orig_sn, orig_metric; 384 unsigned long orig_lifetime, exp_time; 385 u32 last_hop_metric, new_metric; 386 bool process = true; 387 388 rcu_read_lock(); 389 sta = sta_info_get(sdata, mgmt->sa); 390 if (!sta) { 391 rcu_read_unlock(); 392 return 0; 393 } 394 395 last_hop_metric = airtime_link_metric_get(local, sta); 396 /* Update and check originator routing info */ 397 fresh_info = true; 398 399 switch (action) { 400 case MPATH_PREQ: 401 orig_addr = PREQ_IE_ORIG_ADDR(hwmp_ie); 402 orig_sn = PREQ_IE_ORIG_SN(hwmp_ie); 403 orig_lifetime = PREQ_IE_LIFETIME(hwmp_ie); 404 orig_metric = PREQ_IE_METRIC(hwmp_ie); 405 break; 406 case MPATH_PREP: 407 /* Originator here refers to the MP that was the target in the 408 * Path Request. We divert from the nomenclature in the draft 409 * so that we can easily use a single function to gather path 410 * information from both PREQ and PREP frames. 411 */ 412 orig_addr = PREP_IE_TARGET_ADDR(hwmp_ie); 413 orig_sn = PREP_IE_TARGET_SN(hwmp_ie); 414 orig_lifetime = PREP_IE_LIFETIME(hwmp_ie); 415 orig_metric = PREP_IE_METRIC(hwmp_ie); 416 break; 417 default: 418 rcu_read_unlock(); 419 return 0; 420 } 421 new_metric = orig_metric + last_hop_metric; 422 if (new_metric < orig_metric) 423 new_metric = MAX_METRIC; 424 exp_time = TU_TO_EXP_TIME(orig_lifetime); 425 426 if (ether_addr_equal(orig_addr, sdata->vif.addr)) { 427 /* This MP is the originator, we are not interested in this 428 * frame, except for updating transmitter's path info. 429 */ 430 process = false; 431 fresh_info = false; 432 } else { 433 mpath = mesh_path_lookup(sdata, orig_addr); 434 if (mpath) { 435 spin_lock_bh(&mpath->state_lock); 436 if (mpath->flags & MESH_PATH_FIXED) 437 fresh_info = false; 438 else if ((mpath->flags & MESH_PATH_ACTIVE) && 439 (mpath->flags & MESH_PATH_SN_VALID)) { 440 if (SN_GT(mpath->sn, orig_sn) || 441 (mpath->sn == orig_sn && 442 new_metric >= mpath->metric)) { 443 process = false; 444 fresh_info = false; 445 } 446 } 447 } else { 448 mesh_path_add(sdata, orig_addr); 449 mpath = mesh_path_lookup(sdata, orig_addr); 450 if (!mpath) { 451 rcu_read_unlock(); 452 return 0; 453 } 454 spin_lock_bh(&mpath->state_lock); 455 } 456 457 if (fresh_info) { 458 mesh_path_assign_nexthop(mpath, sta); 459 mpath->flags |= MESH_PATH_SN_VALID; 460 mpath->metric = new_metric; 461 mpath->sn = orig_sn; 462 mpath->exp_time = time_after(mpath->exp_time, exp_time) 463 ? mpath->exp_time : exp_time; 464 mesh_path_activate(mpath); 465 spin_unlock_bh(&mpath->state_lock); 466 mesh_path_tx_pending(mpath); 467 /* draft says preq_id should be saved to, but there does 468 * not seem to be any use for it, skipping by now 469 */ 470 } else 471 spin_unlock_bh(&mpath->state_lock); 472 } 473 474 /* Update and check transmitter routing info */ 475 ta = mgmt->sa; 476 if (ether_addr_equal(orig_addr, ta)) 477 fresh_info = false; 478 else { 479 fresh_info = true; 480 481 mpath = mesh_path_lookup(sdata, ta); 482 if (mpath) { 483 spin_lock_bh(&mpath->state_lock); 484 if ((mpath->flags & MESH_PATH_FIXED) || 485 ((mpath->flags & MESH_PATH_ACTIVE) && 486 (last_hop_metric > mpath->metric))) 487 fresh_info = false; 488 } else { 489 mesh_path_add(sdata, ta); 490 mpath = mesh_path_lookup(sdata, ta); 491 if (!mpath) { 492 rcu_read_unlock(); 493 return 0; 494 } 495 spin_lock_bh(&mpath->state_lock); 496 } 497 498 if (fresh_info) { 499 mesh_path_assign_nexthop(mpath, sta); 500 mpath->metric = last_hop_metric; 501 mpath->exp_time = time_after(mpath->exp_time, exp_time) 502 ? mpath->exp_time : exp_time; 503 mesh_path_activate(mpath); 504 spin_unlock_bh(&mpath->state_lock); 505 mesh_path_tx_pending(mpath); 506 } else 507 spin_unlock_bh(&mpath->state_lock); 508 } 509 510 rcu_read_unlock(); 511 512 return process ? new_metric : 0; 513 } 514 515 static void hwmp_preq_frame_process(struct ieee80211_sub_if_data *sdata, 516 struct ieee80211_mgmt *mgmt, 517 const u8 *preq_elem, u32 metric) 518 { 519 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 520 struct mesh_path *mpath = NULL; 521 const u8 *target_addr, *orig_addr; 522 const u8 *da; 523 u8 target_flags, ttl, flags; 524 u32 orig_sn, target_sn, lifetime, orig_metric; 525 bool reply = false; 526 bool forward = true; 527 bool root_is_gate; 528 529 /* Update target SN, if present */ 530 target_addr = PREQ_IE_TARGET_ADDR(preq_elem); 531 orig_addr = PREQ_IE_ORIG_ADDR(preq_elem); 532 target_sn = PREQ_IE_TARGET_SN(preq_elem); 533 orig_sn = PREQ_IE_ORIG_SN(preq_elem); 534 target_flags = PREQ_IE_TARGET_F(preq_elem); 535 orig_metric = metric; 536 /* Proactive PREQ gate announcements */ 537 flags = PREQ_IE_FLAGS(preq_elem); 538 root_is_gate = !!(flags & RANN_FLAG_IS_GATE); 539 540 mhwmp_dbg(sdata, "received PREQ from %pM\n", orig_addr); 541 542 if (ether_addr_equal(target_addr, sdata->vif.addr)) { 543 mhwmp_dbg(sdata, "PREQ is for us\n"); 544 forward = false; 545 reply = true; 546 metric = 0; 547 if (time_after(jiffies, ifmsh->last_sn_update + 548 net_traversal_jiffies(sdata)) || 549 time_before(jiffies, ifmsh->last_sn_update)) { 550 target_sn = ++ifmsh->sn; 551 ifmsh->last_sn_update = jiffies; 552 } 553 } else if (is_broadcast_ether_addr(target_addr) && 554 (target_flags & IEEE80211_PREQ_TO_FLAG)) { 555 rcu_read_lock(); 556 mpath = mesh_path_lookup(sdata, orig_addr); 557 if (mpath) { 558 if (flags & IEEE80211_PREQ_PROACTIVE_PREP_FLAG) { 559 reply = true; 560 target_addr = sdata->vif.addr; 561 target_sn = ++ifmsh->sn; 562 metric = 0; 563 ifmsh->last_sn_update = jiffies; 564 } 565 if (root_is_gate) 566 mesh_path_add_gate(mpath); 567 } 568 rcu_read_unlock(); 569 } else { 570 rcu_read_lock(); 571 mpath = mesh_path_lookup(sdata, target_addr); 572 if (mpath) { 573 if ((!(mpath->flags & MESH_PATH_SN_VALID)) || 574 SN_LT(mpath->sn, target_sn)) { 575 mpath->sn = target_sn; 576 mpath->flags |= MESH_PATH_SN_VALID; 577 } else if ((!(target_flags & MP_F_DO)) && 578 (mpath->flags & MESH_PATH_ACTIVE)) { 579 reply = true; 580 metric = mpath->metric; 581 target_sn = mpath->sn; 582 if (target_flags & MP_F_RF) 583 target_flags |= MP_F_DO; 584 else 585 forward = false; 586 } 587 } 588 rcu_read_unlock(); 589 } 590 591 if (reply) { 592 lifetime = PREQ_IE_LIFETIME(preq_elem); 593 ttl = ifmsh->mshcfg.element_ttl; 594 if (ttl != 0) { 595 mhwmp_dbg(sdata, "replying to the PREQ\n"); 596 mesh_path_sel_frame_tx(MPATH_PREP, 0, orig_addr, 597 cpu_to_le32(orig_sn), 0, target_addr, 598 cpu_to_le32(target_sn), mgmt->sa, 0, ttl, 599 cpu_to_le32(lifetime), cpu_to_le32(metric), 600 0, sdata); 601 } else { 602 ifmsh->mshstats.dropped_frames_ttl++; 603 } 604 } 605 606 if (forward && ifmsh->mshcfg.dot11MeshForwarding) { 607 u32 preq_id; 608 u8 hopcount; 609 610 ttl = PREQ_IE_TTL(preq_elem); 611 lifetime = PREQ_IE_LIFETIME(preq_elem); 612 if (ttl <= 1) { 613 ifmsh->mshstats.dropped_frames_ttl++; 614 return; 615 } 616 mhwmp_dbg(sdata, "forwarding the PREQ from %pM\n", orig_addr); 617 --ttl; 618 preq_id = PREQ_IE_PREQ_ID(preq_elem); 619 hopcount = PREQ_IE_HOPCOUNT(preq_elem) + 1; 620 da = (mpath && mpath->is_root) ? 621 mpath->rann_snd_addr : broadcast_addr; 622 623 if (flags & IEEE80211_PREQ_PROACTIVE_PREP_FLAG) { 624 target_addr = PREQ_IE_TARGET_ADDR(preq_elem); 625 target_sn = PREQ_IE_TARGET_SN(preq_elem); 626 metric = orig_metric; 627 } 628 629 mesh_path_sel_frame_tx(MPATH_PREQ, flags, orig_addr, 630 cpu_to_le32(orig_sn), target_flags, target_addr, 631 cpu_to_le32(target_sn), da, 632 hopcount, ttl, cpu_to_le32(lifetime), 633 cpu_to_le32(metric), cpu_to_le32(preq_id), 634 sdata); 635 if (!is_multicast_ether_addr(da)) 636 ifmsh->mshstats.fwded_unicast++; 637 else 638 ifmsh->mshstats.fwded_mcast++; 639 ifmsh->mshstats.fwded_frames++; 640 } 641 } 642 643 644 static inline struct sta_info * 645 next_hop_deref_protected(struct mesh_path *mpath) 646 { 647 return rcu_dereference_protected(mpath->next_hop, 648 lockdep_is_held(&mpath->state_lock)); 649 } 650 651 652 static void hwmp_prep_frame_process(struct ieee80211_sub_if_data *sdata, 653 struct ieee80211_mgmt *mgmt, 654 const u8 *prep_elem, u32 metric) 655 { 656 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 657 struct mesh_path *mpath; 658 const u8 *target_addr, *orig_addr; 659 u8 ttl, hopcount, flags; 660 u8 next_hop[ETH_ALEN]; 661 u32 target_sn, orig_sn, lifetime; 662 663 mhwmp_dbg(sdata, "received PREP from %pM\n", 664 PREP_IE_ORIG_ADDR(prep_elem)); 665 666 orig_addr = PREP_IE_ORIG_ADDR(prep_elem); 667 if (ether_addr_equal(orig_addr, sdata->vif.addr)) 668 /* destination, no forwarding required */ 669 return; 670 671 if (!ifmsh->mshcfg.dot11MeshForwarding) 672 return; 673 674 ttl = PREP_IE_TTL(prep_elem); 675 if (ttl <= 1) { 676 sdata->u.mesh.mshstats.dropped_frames_ttl++; 677 return; 678 } 679 680 rcu_read_lock(); 681 mpath = mesh_path_lookup(sdata, orig_addr); 682 if (mpath) 683 spin_lock_bh(&mpath->state_lock); 684 else 685 goto fail; 686 if (!(mpath->flags & MESH_PATH_ACTIVE)) { 687 spin_unlock_bh(&mpath->state_lock); 688 goto fail; 689 } 690 memcpy(next_hop, next_hop_deref_protected(mpath)->sta.addr, ETH_ALEN); 691 spin_unlock_bh(&mpath->state_lock); 692 --ttl; 693 flags = PREP_IE_FLAGS(prep_elem); 694 lifetime = PREP_IE_LIFETIME(prep_elem); 695 hopcount = PREP_IE_HOPCOUNT(prep_elem) + 1; 696 target_addr = PREP_IE_TARGET_ADDR(prep_elem); 697 target_sn = PREP_IE_TARGET_SN(prep_elem); 698 orig_sn = PREP_IE_ORIG_SN(prep_elem); 699 700 mesh_path_sel_frame_tx(MPATH_PREP, flags, orig_addr, 701 cpu_to_le32(orig_sn), 0, target_addr, 702 cpu_to_le32(target_sn), next_hop, hopcount, 703 ttl, cpu_to_le32(lifetime), cpu_to_le32(metric), 704 0, sdata); 705 rcu_read_unlock(); 706 707 sdata->u.mesh.mshstats.fwded_unicast++; 708 sdata->u.mesh.mshstats.fwded_frames++; 709 return; 710 711 fail: 712 rcu_read_unlock(); 713 sdata->u.mesh.mshstats.dropped_frames_no_route++; 714 } 715 716 static void hwmp_perr_frame_process(struct ieee80211_sub_if_data *sdata, 717 struct ieee80211_mgmt *mgmt, 718 const u8 *perr_elem) 719 { 720 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 721 struct mesh_path *mpath; 722 u8 ttl; 723 const u8 *ta, *target_addr; 724 u32 target_sn; 725 u16 target_rcode; 726 727 ta = mgmt->sa; 728 ttl = PERR_IE_TTL(perr_elem); 729 if (ttl <= 1) { 730 ifmsh->mshstats.dropped_frames_ttl++; 731 return; 732 } 733 ttl--; 734 target_addr = PERR_IE_TARGET_ADDR(perr_elem); 735 target_sn = PERR_IE_TARGET_SN(perr_elem); 736 target_rcode = PERR_IE_TARGET_RCODE(perr_elem); 737 738 rcu_read_lock(); 739 mpath = mesh_path_lookup(sdata, target_addr); 740 if (mpath) { 741 struct sta_info *sta; 742 743 spin_lock_bh(&mpath->state_lock); 744 sta = next_hop_deref_protected(mpath); 745 if (mpath->flags & MESH_PATH_ACTIVE && 746 ether_addr_equal(ta, sta->sta.addr) && 747 (!(mpath->flags & MESH_PATH_SN_VALID) || 748 SN_GT(target_sn, mpath->sn))) { 749 mpath->flags &= ~MESH_PATH_ACTIVE; 750 mpath->sn = target_sn; 751 spin_unlock_bh(&mpath->state_lock); 752 if (!ifmsh->mshcfg.dot11MeshForwarding) 753 goto endperr; 754 mesh_path_error_tx(sdata, ttl, target_addr, 755 cpu_to_le32(target_sn), 756 cpu_to_le16(target_rcode), 757 broadcast_addr); 758 } else 759 spin_unlock_bh(&mpath->state_lock); 760 } 761 endperr: 762 rcu_read_unlock(); 763 } 764 765 static void hwmp_rann_frame_process(struct ieee80211_sub_if_data *sdata, 766 struct ieee80211_mgmt *mgmt, 767 const struct ieee80211_rann_ie *rann) 768 { 769 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 770 struct ieee80211_local *local = sdata->local; 771 struct sta_info *sta; 772 struct mesh_path *mpath; 773 u8 ttl, flags, hopcount; 774 const u8 *orig_addr; 775 u32 orig_sn, metric, metric_txsta, interval; 776 bool root_is_gate; 777 778 ttl = rann->rann_ttl; 779 flags = rann->rann_flags; 780 root_is_gate = !!(flags & RANN_FLAG_IS_GATE); 781 orig_addr = rann->rann_addr; 782 orig_sn = le32_to_cpu(rann->rann_seq); 783 interval = le32_to_cpu(rann->rann_interval); 784 hopcount = rann->rann_hopcount; 785 hopcount++; 786 metric = le32_to_cpu(rann->rann_metric); 787 788 /* Ignore our own RANNs */ 789 if (ether_addr_equal(orig_addr, sdata->vif.addr)) 790 return; 791 792 mhwmp_dbg(sdata, 793 "received RANN from %pM via neighbour %pM (is_gate=%d)\n", 794 orig_addr, mgmt->sa, root_is_gate); 795 796 rcu_read_lock(); 797 sta = sta_info_get(sdata, mgmt->sa); 798 if (!sta) { 799 rcu_read_unlock(); 800 return; 801 } 802 803 metric_txsta = airtime_link_metric_get(local, sta); 804 805 mpath = mesh_path_lookup(sdata, orig_addr); 806 if (!mpath) { 807 mesh_path_add(sdata, orig_addr); 808 mpath = mesh_path_lookup(sdata, orig_addr); 809 if (!mpath) { 810 rcu_read_unlock(); 811 sdata->u.mesh.mshstats.dropped_frames_no_route++; 812 return; 813 } 814 } 815 816 if (!(SN_LT(mpath->sn, orig_sn)) && 817 !(mpath->sn == orig_sn && metric < mpath->rann_metric)) { 818 rcu_read_unlock(); 819 return; 820 } 821 822 if ((!(mpath->flags & (MESH_PATH_ACTIVE | MESH_PATH_RESOLVING)) || 823 (time_after(jiffies, mpath->last_preq_to_root + 824 root_path_confirmation_jiffies(sdata)) || 825 time_before(jiffies, mpath->last_preq_to_root))) && 826 !(mpath->flags & MESH_PATH_FIXED) && (ttl != 0)) { 827 mhwmp_dbg(sdata, 828 "time to refresh root mpath %pM\n", 829 orig_addr); 830 mesh_queue_preq(mpath, PREQ_Q_F_START | PREQ_Q_F_REFRESH); 831 mpath->last_preq_to_root = jiffies; 832 } 833 834 mpath->sn = orig_sn; 835 mpath->rann_metric = metric + metric_txsta; 836 mpath->is_root = true; 837 /* Recording RANNs sender address to send individually 838 * addressed PREQs destined for root mesh STA */ 839 memcpy(mpath->rann_snd_addr, mgmt->sa, ETH_ALEN); 840 841 if (root_is_gate) 842 mesh_path_add_gate(mpath); 843 844 if (ttl <= 1) { 845 ifmsh->mshstats.dropped_frames_ttl++; 846 rcu_read_unlock(); 847 return; 848 } 849 ttl--; 850 851 if (ifmsh->mshcfg.dot11MeshForwarding) { 852 mesh_path_sel_frame_tx(MPATH_RANN, flags, orig_addr, 853 cpu_to_le32(orig_sn), 854 0, NULL, 0, broadcast_addr, 855 hopcount, ttl, cpu_to_le32(interval), 856 cpu_to_le32(metric + metric_txsta), 857 0, sdata); 858 } 859 860 rcu_read_unlock(); 861 } 862 863 864 void mesh_rx_path_sel_frame(struct ieee80211_sub_if_data *sdata, 865 struct ieee80211_mgmt *mgmt, size_t len) 866 { 867 struct ieee802_11_elems elems; 868 size_t baselen; 869 u32 last_hop_metric; 870 struct sta_info *sta; 871 872 /* need action_code */ 873 if (len < IEEE80211_MIN_ACTION_SIZE + 1) 874 return; 875 876 rcu_read_lock(); 877 sta = sta_info_get(sdata, mgmt->sa); 878 if (!sta || sta->plink_state != NL80211_PLINK_ESTAB) { 879 rcu_read_unlock(); 880 return; 881 } 882 rcu_read_unlock(); 883 884 baselen = (u8 *) mgmt->u.action.u.mesh_action.variable - (u8 *) mgmt; 885 ieee802_11_parse_elems(mgmt->u.action.u.mesh_action.variable, 886 len - baselen, &elems); 887 888 if (elems.preq) { 889 if (elems.preq_len != 37) 890 /* Right now we support just 1 destination and no AE */ 891 return; 892 last_hop_metric = hwmp_route_info_get(sdata, mgmt, elems.preq, 893 MPATH_PREQ); 894 if (last_hop_metric) 895 hwmp_preq_frame_process(sdata, mgmt, elems.preq, 896 last_hop_metric); 897 } 898 if (elems.prep) { 899 if (elems.prep_len != 31) 900 /* Right now we support no AE */ 901 return; 902 last_hop_metric = hwmp_route_info_get(sdata, mgmt, elems.prep, 903 MPATH_PREP); 904 if (last_hop_metric) 905 hwmp_prep_frame_process(sdata, mgmt, elems.prep, 906 last_hop_metric); 907 } 908 if (elems.perr) { 909 if (elems.perr_len != 15) 910 /* Right now we support only one destination per PERR */ 911 return; 912 hwmp_perr_frame_process(sdata, mgmt, elems.perr); 913 } 914 if (elems.rann) 915 hwmp_rann_frame_process(sdata, mgmt, elems.rann); 916 } 917 918 /** 919 * mesh_queue_preq - queue a PREQ to a given destination 920 * 921 * @mpath: mesh path to discover 922 * @flags: special attributes of the PREQ to be sent 923 * 924 * Locking: the function must be called from within a rcu read lock block. 925 * 926 */ 927 static void mesh_queue_preq(struct mesh_path *mpath, u8 flags) 928 { 929 struct ieee80211_sub_if_data *sdata = mpath->sdata; 930 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 931 struct mesh_preq_queue *preq_node; 932 933 preq_node = kmalloc(sizeof(struct mesh_preq_queue), GFP_ATOMIC); 934 if (!preq_node) { 935 mhwmp_dbg(sdata, "could not allocate PREQ node\n"); 936 return; 937 } 938 939 spin_lock_bh(&ifmsh->mesh_preq_queue_lock); 940 if (ifmsh->preq_queue_len == MAX_PREQ_QUEUE_LEN) { 941 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock); 942 kfree(preq_node); 943 if (printk_ratelimit()) 944 mhwmp_dbg(sdata, "PREQ node queue full\n"); 945 return; 946 } 947 948 spin_lock(&mpath->state_lock); 949 if (mpath->flags & MESH_PATH_REQ_QUEUED) { 950 spin_unlock(&mpath->state_lock); 951 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock); 952 kfree(preq_node); 953 return; 954 } 955 956 memcpy(preq_node->dst, mpath->dst, ETH_ALEN); 957 preq_node->flags = flags; 958 959 mpath->flags |= MESH_PATH_REQ_QUEUED; 960 spin_unlock(&mpath->state_lock); 961 962 list_add_tail(&preq_node->list, &ifmsh->preq_queue.list); 963 ++ifmsh->preq_queue_len; 964 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock); 965 966 if (time_after(jiffies, ifmsh->last_preq + min_preq_int_jiff(sdata))) 967 ieee80211_queue_work(&sdata->local->hw, &sdata->work); 968 969 else if (time_before(jiffies, ifmsh->last_preq)) { 970 /* avoid long wait if did not send preqs for a long time 971 * and jiffies wrapped around 972 */ 973 ifmsh->last_preq = jiffies - min_preq_int_jiff(sdata) - 1; 974 ieee80211_queue_work(&sdata->local->hw, &sdata->work); 975 } else 976 mod_timer(&ifmsh->mesh_path_timer, ifmsh->last_preq + 977 min_preq_int_jiff(sdata)); 978 } 979 980 /** 981 * mesh_path_start_discovery - launch a path discovery from the PREQ queue 982 * 983 * @sdata: local mesh subif 984 */ 985 void mesh_path_start_discovery(struct ieee80211_sub_if_data *sdata) 986 { 987 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 988 struct mesh_preq_queue *preq_node; 989 struct mesh_path *mpath; 990 u8 ttl, target_flags; 991 const u8 *da; 992 u32 lifetime; 993 994 spin_lock_bh(&ifmsh->mesh_preq_queue_lock); 995 if (!ifmsh->preq_queue_len || 996 time_before(jiffies, ifmsh->last_preq + 997 min_preq_int_jiff(sdata))) { 998 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock); 999 return; 1000 } 1001 1002 preq_node = list_first_entry(&ifmsh->preq_queue.list, 1003 struct mesh_preq_queue, list); 1004 list_del(&preq_node->list); 1005 --ifmsh->preq_queue_len; 1006 spin_unlock_bh(&ifmsh->mesh_preq_queue_lock); 1007 1008 rcu_read_lock(); 1009 mpath = mesh_path_lookup(sdata, preq_node->dst); 1010 if (!mpath) 1011 goto enddiscovery; 1012 1013 spin_lock_bh(&mpath->state_lock); 1014 mpath->flags &= ~MESH_PATH_REQ_QUEUED; 1015 if (preq_node->flags & PREQ_Q_F_START) { 1016 if (mpath->flags & MESH_PATH_RESOLVING) { 1017 spin_unlock_bh(&mpath->state_lock); 1018 goto enddiscovery; 1019 } else { 1020 mpath->flags &= ~MESH_PATH_RESOLVED; 1021 mpath->flags |= MESH_PATH_RESOLVING; 1022 mpath->discovery_retries = 0; 1023 mpath->discovery_timeout = disc_timeout_jiff(sdata); 1024 } 1025 } else if (!(mpath->flags & MESH_PATH_RESOLVING) || 1026 mpath->flags & MESH_PATH_RESOLVED) { 1027 mpath->flags &= ~MESH_PATH_RESOLVING; 1028 spin_unlock_bh(&mpath->state_lock); 1029 goto enddiscovery; 1030 } 1031 1032 ifmsh->last_preq = jiffies; 1033 1034 if (time_after(jiffies, ifmsh->last_sn_update + 1035 net_traversal_jiffies(sdata)) || 1036 time_before(jiffies, ifmsh->last_sn_update)) { 1037 ++ifmsh->sn; 1038 sdata->u.mesh.last_sn_update = jiffies; 1039 } 1040 lifetime = default_lifetime(sdata); 1041 ttl = sdata->u.mesh.mshcfg.element_ttl; 1042 if (ttl == 0) { 1043 sdata->u.mesh.mshstats.dropped_frames_ttl++; 1044 spin_unlock_bh(&mpath->state_lock); 1045 goto enddiscovery; 1046 } 1047 1048 if (preq_node->flags & PREQ_Q_F_REFRESH) 1049 target_flags = MP_F_DO; 1050 else 1051 target_flags = MP_F_RF; 1052 1053 spin_unlock_bh(&mpath->state_lock); 1054 da = (mpath->is_root) ? mpath->rann_snd_addr : broadcast_addr; 1055 mesh_path_sel_frame_tx(MPATH_PREQ, 0, sdata->vif.addr, 1056 cpu_to_le32(ifmsh->sn), target_flags, mpath->dst, 1057 cpu_to_le32(mpath->sn), da, 0, 1058 ttl, cpu_to_le32(lifetime), 0, 1059 cpu_to_le32(ifmsh->preq_id++), sdata); 1060 mod_timer(&mpath->timer, jiffies + mpath->discovery_timeout); 1061 1062 enddiscovery: 1063 rcu_read_unlock(); 1064 kfree(preq_node); 1065 } 1066 1067 /** 1068 * mesh_nexthop_resolve - lookup next hop; conditionally start path discovery 1069 * 1070 * @skb: 802.11 frame to be sent 1071 * @sdata: network subif the frame will be sent through 1072 * 1073 * Lookup next hop for given skb and start path discovery if no 1074 * forwarding information is found. 1075 * 1076 * Returns: 0 if the next hop was found and -ENOENT if the frame was queued. 1077 * skb is freeed here if no mpath could be allocated. 1078 */ 1079 int mesh_nexthop_resolve(struct ieee80211_sub_if_data *sdata, 1080 struct sk_buff *skb) 1081 { 1082 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 1083 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 1084 struct mesh_path *mpath; 1085 struct sk_buff *skb_to_free = NULL; 1086 u8 *target_addr = hdr->addr3; 1087 int err = 0; 1088 1089 /* Nulls are only sent to peers for PS and should be pre-addressed */ 1090 if (ieee80211_is_qos_nullfunc(hdr->frame_control)) 1091 return 0; 1092 1093 rcu_read_lock(); 1094 err = mesh_nexthop_lookup(sdata, skb); 1095 if (!err) 1096 goto endlookup; 1097 1098 /* no nexthop found, start resolving */ 1099 mpath = mesh_path_lookup(sdata, target_addr); 1100 if (!mpath) { 1101 mesh_path_add(sdata, target_addr); 1102 mpath = mesh_path_lookup(sdata, target_addr); 1103 if (!mpath) { 1104 mesh_path_discard_frame(sdata, skb); 1105 err = -ENOSPC; 1106 goto endlookup; 1107 } 1108 } 1109 1110 if (!(mpath->flags & MESH_PATH_RESOLVING)) 1111 mesh_queue_preq(mpath, PREQ_Q_F_START); 1112 1113 if (skb_queue_len(&mpath->frame_queue) >= MESH_FRAME_QUEUE_LEN) 1114 skb_to_free = skb_dequeue(&mpath->frame_queue); 1115 1116 info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING; 1117 ieee80211_set_qos_hdr(sdata, skb); 1118 skb_queue_tail(&mpath->frame_queue, skb); 1119 err = -ENOENT; 1120 if (skb_to_free) 1121 mesh_path_discard_frame(sdata, skb_to_free); 1122 1123 endlookup: 1124 rcu_read_unlock(); 1125 return err; 1126 } 1127 1128 /** 1129 * mesh_nexthop_lookup - put the appropriate next hop on a mesh frame. Calling 1130 * this function is considered "using" the associated mpath, so preempt a path 1131 * refresh if this mpath expires soon. 1132 * 1133 * @skb: 802.11 frame to be sent 1134 * @sdata: network subif the frame will be sent through 1135 * 1136 * Returns: 0 if the next hop was found. Nonzero otherwise. 1137 */ 1138 int mesh_nexthop_lookup(struct ieee80211_sub_if_data *sdata, 1139 struct sk_buff *skb) 1140 { 1141 struct mesh_path *mpath; 1142 struct sta_info *next_hop; 1143 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 1144 u8 *target_addr = hdr->addr3; 1145 int err = -ENOENT; 1146 1147 rcu_read_lock(); 1148 mpath = mesh_path_lookup(sdata, target_addr); 1149 1150 if (!mpath || !(mpath->flags & MESH_PATH_ACTIVE)) 1151 goto endlookup; 1152 1153 if (time_after(jiffies, 1154 mpath->exp_time - 1155 msecs_to_jiffies(sdata->u.mesh.mshcfg.path_refresh_time)) && 1156 ether_addr_equal(sdata->vif.addr, hdr->addr4) && 1157 !(mpath->flags & MESH_PATH_RESOLVING) && 1158 !(mpath->flags & MESH_PATH_FIXED)) 1159 mesh_queue_preq(mpath, PREQ_Q_F_START | PREQ_Q_F_REFRESH); 1160 1161 next_hop = rcu_dereference(mpath->next_hop); 1162 if (next_hop) { 1163 memcpy(hdr->addr1, next_hop->sta.addr, ETH_ALEN); 1164 memcpy(hdr->addr2, sdata->vif.addr, ETH_ALEN); 1165 ieee80211_mps_set_frame_flags(sdata, next_hop, hdr); 1166 err = 0; 1167 } 1168 1169 endlookup: 1170 rcu_read_unlock(); 1171 return err; 1172 } 1173 1174 void mesh_path_timer(unsigned long data) 1175 { 1176 struct mesh_path *mpath = (void *) data; 1177 struct ieee80211_sub_if_data *sdata = mpath->sdata; 1178 int ret; 1179 1180 if (sdata->local->quiescing) 1181 return; 1182 1183 spin_lock_bh(&mpath->state_lock); 1184 if (mpath->flags & MESH_PATH_RESOLVED || 1185 (!(mpath->flags & MESH_PATH_RESOLVING))) { 1186 mpath->flags &= ~(MESH_PATH_RESOLVING | MESH_PATH_RESOLVED); 1187 spin_unlock_bh(&mpath->state_lock); 1188 } else if (mpath->discovery_retries < max_preq_retries(sdata)) { 1189 ++mpath->discovery_retries; 1190 mpath->discovery_timeout *= 2; 1191 mpath->flags &= ~MESH_PATH_REQ_QUEUED; 1192 spin_unlock_bh(&mpath->state_lock); 1193 mesh_queue_preq(mpath, 0); 1194 } else { 1195 mpath->flags = 0; 1196 mpath->exp_time = jiffies; 1197 spin_unlock_bh(&mpath->state_lock); 1198 if (!mpath->is_gate && mesh_gate_num(sdata) > 0) { 1199 ret = mesh_path_send_to_gates(mpath); 1200 if (ret) 1201 mhwmp_dbg(sdata, "no gate was reachable\n"); 1202 } else 1203 mesh_path_flush_pending(mpath); 1204 } 1205 } 1206 1207 void mesh_path_tx_root_frame(struct ieee80211_sub_if_data *sdata) 1208 { 1209 struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; 1210 u32 interval = ifmsh->mshcfg.dot11MeshHWMPRannInterval; 1211 u8 flags, target_flags = 0; 1212 1213 flags = (ifmsh->mshcfg.dot11MeshGateAnnouncementProtocol) 1214 ? RANN_FLAG_IS_GATE : 0; 1215 1216 switch (ifmsh->mshcfg.dot11MeshHWMPRootMode) { 1217 case IEEE80211_PROACTIVE_RANN: 1218 mesh_path_sel_frame_tx(MPATH_RANN, flags, sdata->vif.addr, 1219 cpu_to_le32(++ifmsh->sn), 1220 0, NULL, 0, broadcast_addr, 1221 0, ifmsh->mshcfg.element_ttl, 1222 cpu_to_le32(interval), 0, 0, sdata); 1223 break; 1224 case IEEE80211_PROACTIVE_PREQ_WITH_PREP: 1225 flags |= IEEE80211_PREQ_PROACTIVE_PREP_FLAG; 1226 case IEEE80211_PROACTIVE_PREQ_NO_PREP: 1227 interval = ifmsh->mshcfg.dot11MeshHWMPactivePathToRootTimeout; 1228 target_flags |= IEEE80211_PREQ_TO_FLAG | 1229 IEEE80211_PREQ_USN_FLAG; 1230 mesh_path_sel_frame_tx(MPATH_PREQ, flags, sdata->vif.addr, 1231 cpu_to_le32(++ifmsh->sn), target_flags, 1232 (u8 *) broadcast_addr, 0, broadcast_addr, 1233 0, ifmsh->mshcfg.element_ttl, 1234 cpu_to_le32(interval), 1235 0, cpu_to_le32(ifmsh->preq_id++), sdata); 1236 break; 1237 default: 1238 mhwmp_dbg(sdata, "Proactive mechanism not supported\n"); 1239 return; 1240 } 1241 } 1242