1 /* 2 * Copyright 2002-2005, Instant802 Networks, Inc. 3 * Copyright 2005-2006, Devicescape Software, Inc. 4 * Copyright 2006-2007 Jiri Benc <jbenc@suse.cz> 5 * Copyright 2007 Johannes Berg <johannes@sipsolutions.net> 6 * 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License version 2 as 9 * published by the Free Software Foundation. 10 * 11 * 12 * Transmit and frame generation functions. 13 */ 14 15 #include <linux/kernel.h> 16 #include <linux/slab.h> 17 #include <linux/skbuff.h> 18 #include <linux/etherdevice.h> 19 #include <linux/bitmap.h> 20 #include <linux/rcupdate.h> 21 #include <net/net_namespace.h> 22 #include <net/ieee80211_radiotap.h> 23 #include <net/cfg80211.h> 24 #include <net/mac80211.h> 25 #include <asm/unaligned.h> 26 27 #include "ieee80211_i.h" 28 #include "driver-ops.h" 29 #include "led.h" 30 #include "mesh.h" 31 #include "wep.h" 32 #include "wpa.h" 33 #include "wme.h" 34 #include "rate.h" 35 36 #define IEEE80211_TX_OK 0 37 #define IEEE80211_TX_AGAIN 1 38 #define IEEE80211_TX_PENDING 2 39 40 /* misc utils */ 41 42 static __le16 ieee80211_duration(struct ieee80211_tx_data *tx, int group_addr, 43 int next_frag_len) 44 { 45 int rate, mrate, erp, dur, i; 46 struct ieee80211_rate *txrate; 47 struct ieee80211_local *local = tx->local; 48 struct ieee80211_supported_band *sband; 49 struct ieee80211_hdr *hdr; 50 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb); 51 52 /* assume HW handles this */ 53 if (info->control.rates[0].flags & IEEE80211_TX_RC_MCS) 54 return 0; 55 56 /* uh huh? */ 57 if (WARN_ON_ONCE(info->control.rates[0].idx < 0)) 58 return 0; 59 60 sband = local->hw.wiphy->bands[tx->channel->band]; 61 txrate = &sband->bitrates[info->control.rates[0].idx]; 62 63 erp = txrate->flags & IEEE80211_RATE_ERP_G; 64 65 /* 66 * data and mgmt (except PS Poll): 67 * - during CFP: 32768 68 * - during contention period: 69 * if addr1 is group address: 0 70 * if more fragments = 0 and addr1 is individual address: time to 71 * transmit one ACK plus SIFS 72 * if more fragments = 1 and addr1 is individual address: time to 73 * transmit next fragment plus 2 x ACK plus 3 x SIFS 74 * 75 * IEEE 802.11, 9.6: 76 * - control response frame (CTS or ACK) shall be transmitted using the 77 * same rate as the immediately previous frame in the frame exchange 78 * sequence, if this rate belongs to the PHY mandatory rates, or else 79 * at the highest possible rate belonging to the PHY rates in the 80 * BSSBasicRateSet 81 */ 82 hdr = (struct ieee80211_hdr *)tx->skb->data; 83 if (ieee80211_is_ctl(hdr->frame_control)) { 84 /* TODO: These control frames are not currently sent by 85 * mac80211, but should they be implemented, this function 86 * needs to be updated to support duration field calculation. 87 * 88 * RTS: time needed to transmit pending data/mgmt frame plus 89 * one CTS frame plus one ACK frame plus 3 x SIFS 90 * CTS: duration of immediately previous RTS minus time 91 * required to transmit CTS and its SIFS 92 * ACK: 0 if immediately previous directed data/mgmt had 93 * more=0, with more=1 duration in ACK frame is duration 94 * from previous frame minus time needed to transmit ACK 95 * and its SIFS 96 * PS Poll: BIT(15) | BIT(14) | aid 97 */ 98 return 0; 99 } 100 101 /* data/mgmt */ 102 if (0 /* FIX: data/mgmt during CFP */) 103 return cpu_to_le16(32768); 104 105 if (group_addr) /* Group address as the destination - no ACK */ 106 return 0; 107 108 /* Individual destination address: 109 * IEEE 802.11, Ch. 9.6 (after IEEE 802.11g changes) 110 * CTS and ACK frames shall be transmitted using the highest rate in 111 * basic rate set that is less than or equal to the rate of the 112 * immediately previous frame and that is using the same modulation 113 * (CCK or OFDM). If no basic rate set matches with these requirements, 114 * the highest mandatory rate of the PHY that is less than or equal to 115 * the rate of the previous frame is used. 116 * Mandatory rates for IEEE 802.11g PHY: 1, 2, 5.5, 11, 6, 12, 24 Mbps 117 */ 118 rate = -1; 119 /* use lowest available if everything fails */ 120 mrate = sband->bitrates[0].bitrate; 121 for (i = 0; i < sband->n_bitrates; i++) { 122 struct ieee80211_rate *r = &sband->bitrates[i]; 123 124 if (r->bitrate > txrate->bitrate) 125 break; 126 127 if (tx->sdata->vif.bss_conf.basic_rates & BIT(i)) 128 rate = r->bitrate; 129 130 switch (sband->band) { 131 case IEEE80211_BAND_2GHZ: { 132 u32 flag; 133 if (tx->sdata->flags & IEEE80211_SDATA_OPERATING_GMODE) 134 flag = IEEE80211_RATE_MANDATORY_G; 135 else 136 flag = IEEE80211_RATE_MANDATORY_B; 137 if (r->flags & flag) 138 mrate = r->bitrate; 139 break; 140 } 141 case IEEE80211_BAND_5GHZ: 142 if (r->flags & IEEE80211_RATE_MANDATORY_A) 143 mrate = r->bitrate; 144 break; 145 case IEEE80211_NUM_BANDS: 146 WARN_ON(1); 147 break; 148 } 149 } 150 if (rate == -1) { 151 /* No matching basic rate found; use highest suitable mandatory 152 * PHY rate */ 153 rate = mrate; 154 } 155 156 /* Time needed to transmit ACK 157 * (10 bytes + 4-byte FCS = 112 bits) plus SIFS; rounded up 158 * to closest integer */ 159 160 dur = ieee80211_frame_duration(local, 10, rate, erp, 161 tx->sdata->vif.bss_conf.use_short_preamble); 162 163 if (next_frag_len) { 164 /* Frame is fragmented: duration increases with time needed to 165 * transmit next fragment plus ACK and 2 x SIFS. */ 166 dur *= 2; /* ACK + SIFS */ 167 /* next fragment */ 168 dur += ieee80211_frame_duration(local, next_frag_len, 169 txrate->bitrate, erp, 170 tx->sdata->vif.bss_conf.use_short_preamble); 171 } 172 173 return cpu_to_le16(dur); 174 } 175 176 static int inline is_ieee80211_device(struct ieee80211_local *local, 177 struct net_device *dev) 178 { 179 return local == wdev_priv(dev->ieee80211_ptr); 180 } 181 182 /* tx handlers */ 183 static ieee80211_tx_result debug_noinline 184 ieee80211_tx_h_dynamic_ps(struct ieee80211_tx_data *tx) 185 { 186 struct ieee80211_local *local = tx->local; 187 struct ieee80211_if_managed *ifmgd; 188 189 /* driver doesn't support power save */ 190 if (!(local->hw.flags & IEEE80211_HW_SUPPORTS_PS)) 191 return TX_CONTINUE; 192 193 /* hardware does dynamic power save */ 194 if (local->hw.flags & IEEE80211_HW_SUPPORTS_DYNAMIC_PS) 195 return TX_CONTINUE; 196 197 /* dynamic power save disabled */ 198 if (local->hw.conf.dynamic_ps_timeout <= 0) 199 return TX_CONTINUE; 200 201 /* we are scanning, don't enable power save */ 202 if (local->scanning) 203 return TX_CONTINUE; 204 205 if (!local->ps_sdata) 206 return TX_CONTINUE; 207 208 /* No point if we're going to suspend */ 209 if (local->quiescing) 210 return TX_CONTINUE; 211 212 /* dynamic ps is supported only in managed mode */ 213 if (tx->sdata->vif.type != NL80211_IFTYPE_STATION) 214 return TX_CONTINUE; 215 216 ifmgd = &tx->sdata->u.mgd; 217 218 /* 219 * Don't wakeup from power save if u-apsd is enabled, voip ac has 220 * u-apsd enabled and the frame is in voip class. This effectively 221 * means that even if all access categories have u-apsd enabled, in 222 * practise u-apsd is only used with the voip ac. This is a 223 * workaround for the case when received voip class packets do not 224 * have correct qos tag for some reason, due the network or the 225 * peer application. 226 * 227 * Note: local->uapsd_queues access is racy here. If the value is 228 * changed via debugfs, user needs to reassociate manually to have 229 * everything in sync. 230 */ 231 if ((ifmgd->flags & IEEE80211_STA_UAPSD_ENABLED) 232 && (local->uapsd_queues & IEEE80211_WMM_IE_STA_QOSINFO_AC_VO) 233 && skb_get_queue_mapping(tx->skb) == 0) 234 return TX_CONTINUE; 235 236 if (local->hw.conf.flags & IEEE80211_CONF_PS) { 237 ieee80211_stop_queues_by_reason(&local->hw, 238 IEEE80211_QUEUE_STOP_REASON_PS); 239 ieee80211_queue_work(&local->hw, 240 &local->dynamic_ps_disable_work); 241 } 242 243 mod_timer(&local->dynamic_ps_timer, jiffies + 244 msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout)); 245 246 return TX_CONTINUE; 247 } 248 249 static ieee80211_tx_result debug_noinline 250 ieee80211_tx_h_check_assoc(struct ieee80211_tx_data *tx) 251 { 252 253 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data; 254 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb); 255 u32 sta_flags; 256 257 if (unlikely(info->flags & IEEE80211_TX_CTL_INJECTED)) 258 return TX_CONTINUE; 259 260 if (unlikely(test_bit(SCAN_OFF_CHANNEL, &tx->local->scanning)) && 261 !ieee80211_is_probe_req(hdr->frame_control) && 262 !ieee80211_is_nullfunc(hdr->frame_control)) 263 /* 264 * When software scanning only nullfunc frames (to notify 265 * the sleep state to the AP) and probe requests (for the 266 * active scan) are allowed, all other frames should not be 267 * sent and we should not get here, but if we do 268 * nonetheless, drop them to avoid sending them 269 * off-channel. See the link below and 270 * ieee80211_start_scan() for more. 271 * 272 * http://article.gmane.org/gmane.linux.kernel.wireless.general/30089 273 */ 274 return TX_DROP; 275 276 if (tx->sdata->vif.type == NL80211_IFTYPE_MESH_POINT) 277 return TX_CONTINUE; 278 279 if (tx->flags & IEEE80211_TX_PS_BUFFERED) 280 return TX_CONTINUE; 281 282 sta_flags = tx->sta ? get_sta_flags(tx->sta) : 0; 283 284 if (likely(tx->flags & IEEE80211_TX_UNICAST)) { 285 if (unlikely(!(sta_flags & WLAN_STA_ASSOC) && 286 tx->sdata->vif.type != NL80211_IFTYPE_ADHOC && 287 ieee80211_is_data(hdr->frame_control))) { 288 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG 289 printk(KERN_DEBUG "%s: dropped data frame to not " 290 "associated station %pM\n", 291 tx->sdata->name, hdr->addr1); 292 #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */ 293 I802_DEBUG_INC(tx->local->tx_handlers_drop_not_assoc); 294 return TX_DROP; 295 } 296 } else { 297 if (unlikely(ieee80211_is_data(hdr->frame_control) && 298 tx->local->num_sta == 0 && 299 tx->sdata->vif.type != NL80211_IFTYPE_ADHOC)) { 300 /* 301 * No associated STAs - no need to send multicast 302 * frames. 303 */ 304 return TX_DROP; 305 } 306 return TX_CONTINUE; 307 } 308 309 return TX_CONTINUE; 310 } 311 312 /* This function is called whenever the AP is about to exceed the maximum limit 313 * of buffered frames for power saving STAs. This situation should not really 314 * happen often during normal operation, so dropping the oldest buffered packet 315 * from each queue should be OK to make some room for new frames. */ 316 static void purge_old_ps_buffers(struct ieee80211_local *local) 317 { 318 int total = 0, purged = 0; 319 struct sk_buff *skb; 320 struct ieee80211_sub_if_data *sdata; 321 struct sta_info *sta; 322 323 /* 324 * virtual interfaces are protected by RCU 325 */ 326 rcu_read_lock(); 327 328 list_for_each_entry_rcu(sdata, &local->interfaces, list) { 329 struct ieee80211_if_ap *ap; 330 if (sdata->vif.type != NL80211_IFTYPE_AP) 331 continue; 332 ap = &sdata->u.ap; 333 skb = skb_dequeue(&ap->ps_bc_buf); 334 if (skb) { 335 purged++; 336 dev_kfree_skb(skb); 337 } 338 total += skb_queue_len(&ap->ps_bc_buf); 339 } 340 341 list_for_each_entry_rcu(sta, &local->sta_list, list) { 342 skb = skb_dequeue(&sta->ps_tx_buf); 343 if (skb) { 344 purged++; 345 dev_kfree_skb(skb); 346 } 347 total += skb_queue_len(&sta->ps_tx_buf); 348 } 349 350 rcu_read_unlock(); 351 352 local->total_ps_buffered = total; 353 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 354 printk(KERN_DEBUG "%s: PS buffers full - purged %d frames\n", 355 wiphy_name(local->hw.wiphy), purged); 356 #endif 357 } 358 359 static ieee80211_tx_result 360 ieee80211_tx_h_multicast_ps_buf(struct ieee80211_tx_data *tx) 361 { 362 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb); 363 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data; 364 365 /* 366 * broadcast/multicast frame 367 * 368 * If any of the associated stations is in power save mode, 369 * the frame is buffered to be sent after DTIM beacon frame. 370 * This is done either by the hardware or us. 371 */ 372 373 /* powersaving STAs only in AP/VLAN mode */ 374 if (!tx->sdata->bss) 375 return TX_CONTINUE; 376 377 /* no buffering for ordered frames */ 378 if (ieee80211_has_order(hdr->frame_control)) 379 return TX_CONTINUE; 380 381 /* no stations in PS mode */ 382 if (!atomic_read(&tx->sdata->bss->num_sta_ps)) 383 return TX_CONTINUE; 384 385 info->flags |= IEEE80211_TX_CTL_SEND_AFTER_DTIM; 386 387 /* device releases frame after DTIM beacon */ 388 if (!(tx->local->hw.flags & IEEE80211_HW_HOST_BROADCAST_PS_BUFFERING)) 389 return TX_CONTINUE; 390 391 /* buffered in mac80211 */ 392 if (tx->local->total_ps_buffered >= TOTAL_MAX_TX_BUFFER) 393 purge_old_ps_buffers(tx->local); 394 395 if (skb_queue_len(&tx->sdata->bss->ps_bc_buf) >= AP_MAX_BC_BUFFER) { 396 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 397 if (net_ratelimit()) 398 printk(KERN_DEBUG "%s: BC TX buffer full - dropping the oldest frame\n", 399 tx->sdata->name); 400 #endif 401 dev_kfree_skb(skb_dequeue(&tx->sdata->bss->ps_bc_buf)); 402 } else 403 tx->local->total_ps_buffered++; 404 405 skb_queue_tail(&tx->sdata->bss->ps_bc_buf, tx->skb); 406 407 return TX_QUEUED; 408 } 409 410 static int ieee80211_use_mfp(__le16 fc, struct sta_info *sta, 411 struct sk_buff *skb) 412 { 413 if (!ieee80211_is_mgmt(fc)) 414 return 0; 415 416 if (sta == NULL || !test_sta_flags(sta, WLAN_STA_MFP)) 417 return 0; 418 419 if (!ieee80211_is_robust_mgmt_frame((struct ieee80211_hdr *) 420 skb->data)) 421 return 0; 422 423 return 1; 424 } 425 426 static ieee80211_tx_result 427 ieee80211_tx_h_unicast_ps_buf(struct ieee80211_tx_data *tx) 428 { 429 struct sta_info *sta = tx->sta; 430 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb); 431 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data; 432 struct ieee80211_local *local = tx->local; 433 u32 staflags; 434 435 if (unlikely(!sta || 436 ieee80211_is_probe_resp(hdr->frame_control) || 437 ieee80211_is_auth(hdr->frame_control) || 438 ieee80211_is_assoc_resp(hdr->frame_control) || 439 ieee80211_is_reassoc_resp(hdr->frame_control))) 440 return TX_CONTINUE; 441 442 staflags = get_sta_flags(sta); 443 444 if (unlikely((staflags & (WLAN_STA_PS_STA | WLAN_STA_PS_DRIVER)) && 445 !(info->flags & IEEE80211_TX_CTL_PSPOLL_RESPONSE))) { 446 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 447 printk(KERN_DEBUG "STA %pM aid %d: PS buffer (entries " 448 "before %d)\n", 449 sta->sta.addr, sta->sta.aid, 450 skb_queue_len(&sta->ps_tx_buf)); 451 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 452 if (tx->local->total_ps_buffered >= TOTAL_MAX_TX_BUFFER) 453 purge_old_ps_buffers(tx->local); 454 if (skb_queue_len(&sta->ps_tx_buf) >= STA_MAX_TX_BUFFER) { 455 struct sk_buff *old = skb_dequeue(&sta->ps_tx_buf); 456 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 457 if (net_ratelimit()) { 458 printk(KERN_DEBUG "%s: STA %pM TX " 459 "buffer full - dropping oldest frame\n", 460 tx->sdata->name, sta->sta.addr); 461 } 462 #endif 463 dev_kfree_skb(old); 464 } else 465 tx->local->total_ps_buffered++; 466 467 /* 468 * Queue frame to be sent after STA wakes up/polls, 469 * but don't set the TIM bit if the driver is blocking 470 * wakeup or poll response transmissions anyway. 471 */ 472 if (skb_queue_empty(&sta->ps_tx_buf) && 473 !(staflags & WLAN_STA_PS_DRIVER)) 474 sta_info_set_tim_bit(sta); 475 476 info->control.jiffies = jiffies; 477 info->control.vif = &tx->sdata->vif; 478 info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING; 479 skb_queue_tail(&sta->ps_tx_buf, tx->skb); 480 481 if (!timer_pending(&local->sta_cleanup)) 482 mod_timer(&local->sta_cleanup, 483 round_jiffies(jiffies + 484 STA_INFO_CLEANUP_INTERVAL)); 485 486 return TX_QUEUED; 487 } 488 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 489 else if (unlikely(staflags & WLAN_STA_PS_STA)) { 490 printk(KERN_DEBUG "%s: STA %pM in PS mode, but pspoll " 491 "set -> send frame\n", tx->sdata->name, 492 sta->sta.addr); 493 } 494 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 495 496 return TX_CONTINUE; 497 } 498 499 static ieee80211_tx_result debug_noinline 500 ieee80211_tx_h_ps_buf(struct ieee80211_tx_data *tx) 501 { 502 if (unlikely(tx->flags & IEEE80211_TX_PS_BUFFERED)) 503 return TX_CONTINUE; 504 505 if (tx->flags & IEEE80211_TX_UNICAST) 506 return ieee80211_tx_h_unicast_ps_buf(tx); 507 else 508 return ieee80211_tx_h_multicast_ps_buf(tx); 509 } 510 511 static ieee80211_tx_result debug_noinline 512 ieee80211_tx_h_select_key(struct ieee80211_tx_data *tx) 513 { 514 struct ieee80211_key *key = NULL; 515 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb); 516 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data; 517 518 if (unlikely(info->flags & IEEE80211_TX_INTFL_DONT_ENCRYPT)) 519 tx->key = NULL; 520 else if (tx->sta && (key = rcu_dereference(tx->sta->key))) 521 tx->key = key; 522 else if (ieee80211_is_mgmt(hdr->frame_control) && 523 is_multicast_ether_addr(hdr->addr1) && 524 ieee80211_is_robust_mgmt_frame(hdr) && 525 (key = rcu_dereference(tx->sdata->default_mgmt_key))) 526 tx->key = key; 527 else if ((key = rcu_dereference(tx->sdata->default_key))) 528 tx->key = key; 529 else if (tx->sdata->drop_unencrypted && 530 (tx->skb->protocol != cpu_to_be16(ETH_P_PAE)) && 531 !(info->flags & IEEE80211_TX_CTL_INJECTED) && 532 (!ieee80211_is_robust_mgmt_frame(hdr) || 533 (ieee80211_is_action(hdr->frame_control) && 534 tx->sta && test_sta_flags(tx->sta, WLAN_STA_MFP)))) { 535 I802_DEBUG_INC(tx->local->tx_handlers_drop_unencrypted); 536 return TX_DROP; 537 } else 538 tx->key = NULL; 539 540 if (tx->key) { 541 bool skip_hw = false; 542 543 tx->key->tx_rx_count++; 544 /* TODO: add threshold stuff again */ 545 546 switch (tx->key->conf.alg) { 547 case ALG_WEP: 548 if (ieee80211_is_auth(hdr->frame_control)) 549 break; 550 case ALG_TKIP: 551 if (!ieee80211_is_data_present(hdr->frame_control)) 552 tx->key = NULL; 553 break; 554 case ALG_CCMP: 555 if (!ieee80211_is_data_present(hdr->frame_control) && 556 !ieee80211_use_mfp(hdr->frame_control, tx->sta, 557 tx->skb)) 558 tx->key = NULL; 559 else 560 skip_hw = (tx->key->conf.flags & 561 IEEE80211_KEY_FLAG_SW_MGMT) && 562 ieee80211_is_mgmt(hdr->frame_control); 563 break; 564 case ALG_AES_CMAC: 565 if (!ieee80211_is_mgmt(hdr->frame_control)) 566 tx->key = NULL; 567 break; 568 } 569 570 if (!skip_hw && tx->key && 571 tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) 572 info->control.hw_key = &tx->key->conf; 573 } 574 575 return TX_CONTINUE; 576 } 577 578 static ieee80211_tx_result debug_noinline 579 ieee80211_tx_h_rate_ctrl(struct ieee80211_tx_data *tx) 580 { 581 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb); 582 struct ieee80211_hdr *hdr = (void *)tx->skb->data; 583 struct ieee80211_supported_band *sband; 584 struct ieee80211_rate *rate; 585 int i; 586 u32 len; 587 bool inval = false, rts = false, short_preamble = false; 588 struct ieee80211_tx_rate_control txrc; 589 u32 sta_flags; 590 591 memset(&txrc, 0, sizeof(txrc)); 592 593 sband = tx->local->hw.wiphy->bands[tx->channel->band]; 594 595 len = min_t(u32, tx->skb->len + FCS_LEN, 596 tx->local->hw.wiphy->frag_threshold); 597 598 /* set up the tx rate control struct we give the RC algo */ 599 txrc.hw = local_to_hw(tx->local); 600 txrc.sband = sband; 601 txrc.bss_conf = &tx->sdata->vif.bss_conf; 602 txrc.skb = tx->skb; 603 txrc.reported_rate.idx = -1; 604 txrc.rate_idx_mask = tx->sdata->rc_rateidx_mask[tx->channel->band]; 605 if (txrc.rate_idx_mask == (1 << sband->n_bitrates) - 1) 606 txrc.max_rate_idx = -1; 607 else 608 txrc.max_rate_idx = fls(txrc.rate_idx_mask) - 1; 609 txrc.ap = tx->sdata->vif.type == NL80211_IFTYPE_AP; 610 611 /* set up RTS protection if desired */ 612 if (len > tx->local->hw.wiphy->rts_threshold) { 613 txrc.rts = rts = true; 614 } 615 616 /* 617 * Use short preamble if the BSS can handle it, but not for 618 * management frames unless we know the receiver can handle 619 * that -- the management frame might be to a station that 620 * just wants a probe response. 621 */ 622 if (tx->sdata->vif.bss_conf.use_short_preamble && 623 (ieee80211_is_data(hdr->frame_control) || 624 (tx->sta && test_sta_flags(tx->sta, WLAN_STA_SHORT_PREAMBLE)))) 625 txrc.short_preamble = short_preamble = true; 626 627 sta_flags = tx->sta ? get_sta_flags(tx->sta) : 0; 628 629 /* 630 * Lets not bother rate control if we're associated and cannot 631 * talk to the sta. This should not happen. 632 */ 633 if (WARN(test_bit(SCAN_SW_SCANNING, &tx->local->scanning) && 634 (sta_flags & WLAN_STA_ASSOC) && 635 !rate_usable_index_exists(sband, &tx->sta->sta), 636 "%s: Dropped data frame as no usable bitrate found while " 637 "scanning and associated. Target station: " 638 "%pM on %d GHz band\n", 639 tx->sdata->name, hdr->addr1, 640 tx->channel->band ? 5 : 2)) 641 return TX_DROP; 642 643 /* 644 * If we're associated with the sta at this point we know we can at 645 * least send the frame at the lowest bit rate. 646 */ 647 rate_control_get_rate(tx->sdata, tx->sta, &txrc); 648 649 if (unlikely(info->control.rates[0].idx < 0)) 650 return TX_DROP; 651 652 if (txrc.reported_rate.idx < 0) 653 txrc.reported_rate = info->control.rates[0]; 654 655 if (tx->sta) 656 tx->sta->last_tx_rate = txrc.reported_rate; 657 658 if (unlikely(!info->control.rates[0].count)) 659 info->control.rates[0].count = 1; 660 661 if (WARN_ON_ONCE((info->control.rates[0].count > 1) && 662 (info->flags & IEEE80211_TX_CTL_NO_ACK))) 663 info->control.rates[0].count = 1; 664 665 if (is_multicast_ether_addr(hdr->addr1)) { 666 /* 667 * XXX: verify the rate is in the basic rateset 668 */ 669 return TX_CONTINUE; 670 } 671 672 /* 673 * set up the RTS/CTS rate as the fastest basic rate 674 * that is not faster than the data rate 675 * 676 * XXX: Should this check all retry rates? 677 */ 678 if (!(info->control.rates[0].flags & IEEE80211_TX_RC_MCS)) { 679 s8 baserate = 0; 680 681 rate = &sband->bitrates[info->control.rates[0].idx]; 682 683 for (i = 0; i < sband->n_bitrates; i++) { 684 /* must be a basic rate */ 685 if (!(tx->sdata->vif.bss_conf.basic_rates & BIT(i))) 686 continue; 687 /* must not be faster than the data rate */ 688 if (sband->bitrates[i].bitrate > rate->bitrate) 689 continue; 690 /* maximum */ 691 if (sband->bitrates[baserate].bitrate < 692 sband->bitrates[i].bitrate) 693 baserate = i; 694 } 695 696 info->control.rts_cts_rate_idx = baserate; 697 } 698 699 for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) { 700 /* 701 * make sure there's no valid rate following 702 * an invalid one, just in case drivers don't 703 * take the API seriously to stop at -1. 704 */ 705 if (inval) { 706 info->control.rates[i].idx = -1; 707 continue; 708 } 709 if (info->control.rates[i].idx < 0) { 710 inval = true; 711 continue; 712 } 713 714 /* 715 * For now assume MCS is already set up correctly, this 716 * needs to be fixed. 717 */ 718 if (info->control.rates[i].flags & IEEE80211_TX_RC_MCS) { 719 WARN_ON(info->control.rates[i].idx > 76); 720 continue; 721 } 722 723 /* set up RTS protection if desired */ 724 if (rts) 725 info->control.rates[i].flags |= 726 IEEE80211_TX_RC_USE_RTS_CTS; 727 728 /* RC is busted */ 729 if (WARN_ON_ONCE(info->control.rates[i].idx >= 730 sband->n_bitrates)) { 731 info->control.rates[i].idx = -1; 732 continue; 733 } 734 735 rate = &sband->bitrates[info->control.rates[i].idx]; 736 737 /* set up short preamble */ 738 if (short_preamble && 739 rate->flags & IEEE80211_RATE_SHORT_PREAMBLE) 740 info->control.rates[i].flags |= 741 IEEE80211_TX_RC_USE_SHORT_PREAMBLE; 742 743 /* set up G protection */ 744 if (!rts && tx->sdata->vif.bss_conf.use_cts_prot && 745 rate->flags & IEEE80211_RATE_ERP_G) 746 info->control.rates[i].flags |= 747 IEEE80211_TX_RC_USE_CTS_PROTECT; 748 } 749 750 return TX_CONTINUE; 751 } 752 753 static ieee80211_tx_result debug_noinline 754 ieee80211_tx_h_sequence(struct ieee80211_tx_data *tx) 755 { 756 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb); 757 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data; 758 u16 *seq; 759 u8 *qc; 760 int tid; 761 762 /* 763 * Packet injection may want to control the sequence 764 * number, if we have no matching interface then we 765 * neither assign one ourselves nor ask the driver to. 766 */ 767 if (unlikely(info->control.vif->type == NL80211_IFTYPE_MONITOR)) 768 return TX_CONTINUE; 769 770 if (unlikely(ieee80211_is_ctl(hdr->frame_control))) 771 return TX_CONTINUE; 772 773 if (ieee80211_hdrlen(hdr->frame_control) < 24) 774 return TX_CONTINUE; 775 776 /* 777 * Anything but QoS data that has a sequence number field 778 * (is long enough) gets a sequence number from the global 779 * counter. 780 */ 781 if (!ieee80211_is_data_qos(hdr->frame_control)) { 782 /* driver should assign sequence number */ 783 info->flags |= IEEE80211_TX_CTL_ASSIGN_SEQ; 784 /* for pure STA mode without beacons, we can do it */ 785 hdr->seq_ctrl = cpu_to_le16(tx->sdata->sequence_number); 786 tx->sdata->sequence_number += 0x10; 787 return TX_CONTINUE; 788 } 789 790 /* 791 * This should be true for injected/management frames only, for 792 * management frames we have set the IEEE80211_TX_CTL_ASSIGN_SEQ 793 * above since they are not QoS-data frames. 794 */ 795 if (!tx->sta) 796 return TX_CONTINUE; 797 798 /* include per-STA, per-TID sequence counter */ 799 800 qc = ieee80211_get_qos_ctl(hdr); 801 tid = *qc & IEEE80211_QOS_CTL_TID_MASK; 802 seq = &tx->sta->tid_seq[tid]; 803 804 hdr->seq_ctrl = cpu_to_le16(*seq); 805 806 /* Increase the sequence number. */ 807 *seq = (*seq + 0x10) & IEEE80211_SCTL_SEQ; 808 809 return TX_CONTINUE; 810 } 811 812 static int ieee80211_fragment(struct ieee80211_local *local, 813 struct sk_buff *skb, int hdrlen, 814 int frag_threshold) 815 { 816 struct sk_buff *tail = skb, *tmp; 817 int per_fragm = frag_threshold - hdrlen - FCS_LEN; 818 int pos = hdrlen + per_fragm; 819 int rem = skb->len - hdrlen - per_fragm; 820 821 if (WARN_ON(rem < 0)) 822 return -EINVAL; 823 824 while (rem) { 825 int fraglen = per_fragm; 826 827 if (fraglen > rem) 828 fraglen = rem; 829 rem -= fraglen; 830 tmp = dev_alloc_skb(local->tx_headroom + 831 frag_threshold + 832 IEEE80211_ENCRYPT_HEADROOM + 833 IEEE80211_ENCRYPT_TAILROOM); 834 if (!tmp) 835 return -ENOMEM; 836 tail->next = tmp; 837 tail = tmp; 838 skb_reserve(tmp, local->tx_headroom + 839 IEEE80211_ENCRYPT_HEADROOM); 840 /* copy control information */ 841 memcpy(tmp->cb, skb->cb, sizeof(tmp->cb)); 842 skb_copy_queue_mapping(tmp, skb); 843 tmp->priority = skb->priority; 844 tmp->dev = skb->dev; 845 846 /* copy header and data */ 847 memcpy(skb_put(tmp, hdrlen), skb->data, hdrlen); 848 memcpy(skb_put(tmp, fraglen), skb->data + pos, fraglen); 849 850 pos += fraglen; 851 } 852 853 skb->len = hdrlen + per_fragm; 854 return 0; 855 } 856 857 static ieee80211_tx_result debug_noinline 858 ieee80211_tx_h_fragment(struct ieee80211_tx_data *tx) 859 { 860 struct sk_buff *skb = tx->skb; 861 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 862 struct ieee80211_hdr *hdr = (void *)skb->data; 863 int frag_threshold = tx->local->hw.wiphy->frag_threshold; 864 int hdrlen; 865 int fragnum; 866 867 if (!(tx->flags & IEEE80211_TX_FRAGMENTED)) 868 return TX_CONTINUE; 869 870 /* 871 * Warn when submitting a fragmented A-MPDU frame and drop it. 872 * This scenario is handled in ieee80211_tx_prepare but extra 873 * caution taken here as fragmented ampdu may cause Tx stop. 874 */ 875 if (WARN_ON(info->flags & IEEE80211_TX_CTL_AMPDU)) 876 return TX_DROP; 877 878 hdrlen = ieee80211_hdrlen(hdr->frame_control); 879 880 /* internal error, why is TX_FRAGMENTED set? */ 881 if (WARN_ON(skb->len + FCS_LEN <= frag_threshold)) 882 return TX_DROP; 883 884 /* 885 * Now fragment the frame. This will allocate all the fragments and 886 * chain them (using skb as the first fragment) to skb->next. 887 * During transmission, we will remove the successfully transmitted 888 * fragments from this list. When the low-level driver rejects one 889 * of the fragments then we will simply pretend to accept the skb 890 * but store it away as pending. 891 */ 892 if (ieee80211_fragment(tx->local, skb, hdrlen, frag_threshold)) 893 return TX_DROP; 894 895 /* update duration/seq/flags of fragments */ 896 fragnum = 0; 897 do { 898 int next_len; 899 const __le16 morefrags = cpu_to_le16(IEEE80211_FCTL_MOREFRAGS); 900 901 hdr = (void *)skb->data; 902 info = IEEE80211_SKB_CB(skb); 903 904 if (skb->next) { 905 hdr->frame_control |= morefrags; 906 next_len = skb->next->len; 907 /* 908 * No multi-rate retries for fragmented frames, that 909 * would completely throw off the NAV at other STAs. 910 */ 911 info->control.rates[1].idx = -1; 912 info->control.rates[2].idx = -1; 913 info->control.rates[3].idx = -1; 914 info->control.rates[4].idx = -1; 915 BUILD_BUG_ON(IEEE80211_TX_MAX_RATES != 5); 916 info->flags &= ~IEEE80211_TX_CTL_RATE_CTRL_PROBE; 917 } else { 918 hdr->frame_control &= ~morefrags; 919 next_len = 0; 920 } 921 hdr->duration_id = ieee80211_duration(tx, 0, next_len); 922 hdr->seq_ctrl |= cpu_to_le16(fragnum & IEEE80211_SCTL_FRAG); 923 fragnum++; 924 } while ((skb = skb->next)); 925 926 return TX_CONTINUE; 927 } 928 929 static ieee80211_tx_result debug_noinline 930 ieee80211_tx_h_stats(struct ieee80211_tx_data *tx) 931 { 932 struct sk_buff *skb = tx->skb; 933 934 if (!tx->sta) 935 return TX_CONTINUE; 936 937 tx->sta->tx_packets++; 938 do { 939 tx->sta->tx_fragments++; 940 tx->sta->tx_bytes += skb->len; 941 } while ((skb = skb->next)); 942 943 return TX_CONTINUE; 944 } 945 946 static ieee80211_tx_result debug_noinline 947 ieee80211_tx_h_encrypt(struct ieee80211_tx_data *tx) 948 { 949 if (!tx->key) 950 return TX_CONTINUE; 951 952 switch (tx->key->conf.alg) { 953 case ALG_WEP: 954 return ieee80211_crypto_wep_encrypt(tx); 955 case ALG_TKIP: 956 return ieee80211_crypto_tkip_encrypt(tx); 957 case ALG_CCMP: 958 return ieee80211_crypto_ccmp_encrypt(tx); 959 case ALG_AES_CMAC: 960 return ieee80211_crypto_aes_cmac_encrypt(tx); 961 } 962 963 /* not reached */ 964 WARN_ON(1); 965 return TX_DROP; 966 } 967 968 static ieee80211_tx_result debug_noinline 969 ieee80211_tx_h_calculate_duration(struct ieee80211_tx_data *tx) 970 { 971 struct sk_buff *skb = tx->skb; 972 struct ieee80211_hdr *hdr; 973 int next_len; 974 bool group_addr; 975 976 do { 977 hdr = (void *) skb->data; 978 if (unlikely(ieee80211_is_pspoll(hdr->frame_control))) 979 break; /* must not overwrite AID */ 980 next_len = skb->next ? skb->next->len : 0; 981 group_addr = is_multicast_ether_addr(hdr->addr1); 982 983 hdr->duration_id = 984 ieee80211_duration(tx, group_addr, next_len); 985 } while ((skb = skb->next)); 986 987 return TX_CONTINUE; 988 } 989 990 /* actual transmit path */ 991 992 /* 993 * deal with packet injection down monitor interface 994 * with Radiotap Header -- only called for monitor mode interface 995 */ 996 static bool __ieee80211_parse_tx_radiotap(struct ieee80211_tx_data *tx, 997 struct sk_buff *skb) 998 { 999 /* 1000 * this is the moment to interpret and discard the radiotap header that 1001 * must be at the start of the packet injected in Monitor mode 1002 * 1003 * Need to take some care with endian-ness since radiotap 1004 * args are little-endian 1005 */ 1006 1007 struct ieee80211_radiotap_iterator iterator; 1008 struct ieee80211_radiotap_header *rthdr = 1009 (struct ieee80211_radiotap_header *) skb->data; 1010 struct ieee80211_supported_band *sband; 1011 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 1012 int ret = ieee80211_radiotap_iterator_init(&iterator, rthdr, skb->len, 1013 NULL); 1014 1015 sband = tx->local->hw.wiphy->bands[tx->channel->band]; 1016 1017 info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT; 1018 tx->flags &= ~IEEE80211_TX_FRAGMENTED; 1019 1020 /* 1021 * for every radiotap entry that is present 1022 * (ieee80211_radiotap_iterator_next returns -ENOENT when no more 1023 * entries present, or -EINVAL on error) 1024 */ 1025 1026 while (!ret) { 1027 ret = ieee80211_radiotap_iterator_next(&iterator); 1028 1029 if (ret) 1030 continue; 1031 1032 /* see if this argument is something we can use */ 1033 switch (iterator.this_arg_index) { 1034 /* 1035 * You must take care when dereferencing iterator.this_arg 1036 * for multibyte types... the pointer is not aligned. Use 1037 * get_unaligned((type *)iterator.this_arg) to dereference 1038 * iterator.this_arg for type "type" safely on all arches. 1039 */ 1040 case IEEE80211_RADIOTAP_FLAGS: 1041 if (*iterator.this_arg & IEEE80211_RADIOTAP_F_FCS) { 1042 /* 1043 * this indicates that the skb we have been 1044 * handed has the 32-bit FCS CRC at the end... 1045 * we should react to that by snipping it off 1046 * because it will be recomputed and added 1047 * on transmission 1048 */ 1049 if (skb->len < (iterator._max_length + FCS_LEN)) 1050 return false; 1051 1052 skb_trim(skb, skb->len - FCS_LEN); 1053 } 1054 if (*iterator.this_arg & IEEE80211_RADIOTAP_F_WEP) 1055 info->flags &= ~IEEE80211_TX_INTFL_DONT_ENCRYPT; 1056 if (*iterator.this_arg & IEEE80211_RADIOTAP_F_FRAG) 1057 tx->flags |= IEEE80211_TX_FRAGMENTED; 1058 break; 1059 1060 /* 1061 * Please update the file 1062 * Documentation/networking/mac80211-injection.txt 1063 * when parsing new fields here. 1064 */ 1065 1066 default: 1067 break; 1068 } 1069 } 1070 1071 if (ret != -ENOENT) /* ie, if we didn't simply run out of fields */ 1072 return false; 1073 1074 /* 1075 * remove the radiotap header 1076 * iterator->_max_length was sanity-checked against 1077 * skb->len by iterator init 1078 */ 1079 skb_pull(skb, iterator._max_length); 1080 1081 return true; 1082 } 1083 1084 static bool ieee80211_tx_prep_agg(struct ieee80211_tx_data *tx, 1085 struct sk_buff *skb, 1086 struct ieee80211_tx_info *info, 1087 struct tid_ampdu_tx *tid_tx, 1088 int tid) 1089 { 1090 bool queued = false; 1091 1092 if (test_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state)) { 1093 info->flags |= IEEE80211_TX_CTL_AMPDU; 1094 } else if (test_bit(HT_AGG_STATE_WANT_START, &tid_tx->state)) { 1095 /* 1096 * nothing -- this aggregation session is being started 1097 * but that might still fail with the driver 1098 */ 1099 } else { 1100 spin_lock(&tx->sta->lock); 1101 /* 1102 * Need to re-check now, because we may get here 1103 * 1104 * 1) in the window during which the setup is actually 1105 * already done, but not marked yet because not all 1106 * packets are spliced over to the driver pending 1107 * queue yet -- if this happened we acquire the lock 1108 * either before or after the splice happens, but 1109 * need to recheck which of these cases happened. 1110 * 1111 * 2) during session teardown, if the OPERATIONAL bit 1112 * was cleared due to the teardown but the pointer 1113 * hasn't been assigned NULL yet (or we loaded it 1114 * before it was assigned) -- in this case it may 1115 * now be NULL which means we should just let the 1116 * packet pass through because splicing the frames 1117 * back is already done. 1118 */ 1119 tid_tx = tx->sta->ampdu_mlme.tid_tx[tid]; 1120 1121 if (!tid_tx) { 1122 /* do nothing, let packet pass through */ 1123 } else if (test_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state)) { 1124 info->flags |= IEEE80211_TX_CTL_AMPDU; 1125 } else { 1126 queued = true; 1127 info->control.vif = &tx->sdata->vif; 1128 info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING; 1129 __skb_queue_tail(&tid_tx->pending, skb); 1130 } 1131 spin_unlock(&tx->sta->lock); 1132 } 1133 1134 return queued; 1135 } 1136 1137 /* 1138 * initialises @tx 1139 */ 1140 static ieee80211_tx_result 1141 ieee80211_tx_prepare(struct ieee80211_sub_if_data *sdata, 1142 struct ieee80211_tx_data *tx, 1143 struct sk_buff *skb) 1144 { 1145 struct ieee80211_local *local = sdata->local; 1146 struct ieee80211_hdr *hdr; 1147 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 1148 int hdrlen, tid; 1149 u8 *qc; 1150 1151 memset(tx, 0, sizeof(*tx)); 1152 tx->skb = skb; 1153 tx->local = local; 1154 tx->sdata = sdata; 1155 tx->channel = local->hw.conf.channel; 1156 /* 1157 * Set this flag (used below to indicate "automatic fragmentation"), 1158 * it will be cleared/left by radiotap as desired. 1159 */ 1160 tx->flags |= IEEE80211_TX_FRAGMENTED; 1161 1162 /* process and remove the injection radiotap header */ 1163 if (unlikely(info->flags & IEEE80211_TX_INTFL_HAS_RADIOTAP)) { 1164 if (!__ieee80211_parse_tx_radiotap(tx, skb)) 1165 return TX_DROP; 1166 1167 /* 1168 * __ieee80211_parse_tx_radiotap has now removed 1169 * the radiotap header that was present and pre-filled 1170 * 'tx' with tx control information. 1171 */ 1172 info->flags &= ~IEEE80211_TX_INTFL_HAS_RADIOTAP; 1173 } 1174 1175 /* 1176 * If this flag is set to true anywhere, and we get here, 1177 * we are doing the needed processing, so remove the flag 1178 * now. 1179 */ 1180 info->flags &= ~IEEE80211_TX_INTFL_NEED_TXPROCESSING; 1181 1182 hdr = (struct ieee80211_hdr *) skb->data; 1183 1184 if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) { 1185 tx->sta = rcu_dereference(sdata->u.vlan.sta); 1186 if (!tx->sta && sdata->dev->ieee80211_ptr->use_4addr) 1187 return TX_DROP; 1188 } else if (info->flags & IEEE80211_TX_CTL_INJECTED) { 1189 tx->sta = sta_info_get_bss(sdata, hdr->addr1); 1190 } 1191 if (!tx->sta) 1192 tx->sta = sta_info_get(sdata, hdr->addr1); 1193 1194 if (tx->sta && ieee80211_is_data_qos(hdr->frame_control) && 1195 (local->hw.flags & IEEE80211_HW_AMPDU_AGGREGATION)) { 1196 struct tid_ampdu_tx *tid_tx; 1197 1198 qc = ieee80211_get_qos_ctl(hdr); 1199 tid = *qc & IEEE80211_QOS_CTL_TID_MASK; 1200 1201 tid_tx = rcu_dereference(tx->sta->ampdu_mlme.tid_tx[tid]); 1202 if (tid_tx) { 1203 bool queued; 1204 1205 queued = ieee80211_tx_prep_agg(tx, skb, info, 1206 tid_tx, tid); 1207 1208 if (unlikely(queued)) 1209 return TX_QUEUED; 1210 } 1211 } 1212 1213 if (is_multicast_ether_addr(hdr->addr1)) { 1214 tx->flags &= ~IEEE80211_TX_UNICAST; 1215 info->flags |= IEEE80211_TX_CTL_NO_ACK; 1216 } else { 1217 tx->flags |= IEEE80211_TX_UNICAST; 1218 if (unlikely(local->wifi_wme_noack_test)) 1219 info->flags |= IEEE80211_TX_CTL_NO_ACK; 1220 else 1221 info->flags &= ~IEEE80211_TX_CTL_NO_ACK; 1222 } 1223 1224 if (tx->flags & IEEE80211_TX_FRAGMENTED) { 1225 if ((tx->flags & IEEE80211_TX_UNICAST) && 1226 skb->len + FCS_LEN > local->hw.wiphy->frag_threshold && 1227 !(info->flags & IEEE80211_TX_CTL_AMPDU)) 1228 tx->flags |= IEEE80211_TX_FRAGMENTED; 1229 else 1230 tx->flags &= ~IEEE80211_TX_FRAGMENTED; 1231 } 1232 1233 if (!tx->sta) 1234 info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT; 1235 else if (test_and_clear_sta_flags(tx->sta, WLAN_STA_CLEAR_PS_FILT)) 1236 info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT; 1237 1238 hdrlen = ieee80211_hdrlen(hdr->frame_control); 1239 if (skb->len > hdrlen + sizeof(rfc1042_header) + 2) { 1240 u8 *pos = &skb->data[hdrlen + sizeof(rfc1042_header)]; 1241 tx->ethertype = (pos[0] << 8) | pos[1]; 1242 } 1243 info->flags |= IEEE80211_TX_CTL_FIRST_FRAGMENT; 1244 1245 return TX_CONTINUE; 1246 } 1247 1248 static int __ieee80211_tx(struct ieee80211_local *local, 1249 struct sk_buff **skbp, 1250 struct sta_info *sta, 1251 bool txpending) 1252 { 1253 struct sk_buff *skb = *skbp, *next; 1254 struct ieee80211_tx_info *info; 1255 struct ieee80211_sub_if_data *sdata; 1256 unsigned long flags; 1257 int ret, len; 1258 bool fragm = false; 1259 1260 while (skb) { 1261 int q = skb_get_queue_mapping(skb); 1262 1263 spin_lock_irqsave(&local->queue_stop_reason_lock, flags); 1264 ret = IEEE80211_TX_OK; 1265 if (local->queue_stop_reasons[q] || 1266 (!txpending && !skb_queue_empty(&local->pending[q]))) 1267 ret = IEEE80211_TX_PENDING; 1268 spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags); 1269 if (ret != IEEE80211_TX_OK) 1270 return ret; 1271 1272 info = IEEE80211_SKB_CB(skb); 1273 1274 if (fragm) 1275 info->flags &= ~(IEEE80211_TX_CTL_CLEAR_PS_FILT | 1276 IEEE80211_TX_CTL_FIRST_FRAGMENT); 1277 1278 next = skb->next; 1279 len = skb->len; 1280 1281 if (next) 1282 info->flags |= IEEE80211_TX_CTL_MORE_FRAMES; 1283 1284 sdata = vif_to_sdata(info->control.vif); 1285 1286 switch (sdata->vif.type) { 1287 case NL80211_IFTYPE_MONITOR: 1288 info->control.vif = NULL; 1289 break; 1290 case NL80211_IFTYPE_AP_VLAN: 1291 info->control.vif = &container_of(sdata->bss, 1292 struct ieee80211_sub_if_data, u.ap)->vif; 1293 break; 1294 default: 1295 /* keep */ 1296 break; 1297 } 1298 1299 if (sta && sta->uploaded) 1300 info->control.sta = &sta->sta; 1301 else 1302 info->control.sta = NULL; 1303 1304 ret = drv_tx(local, skb); 1305 if (WARN_ON(ret != NETDEV_TX_OK && skb->len != len)) { 1306 dev_kfree_skb(skb); 1307 ret = NETDEV_TX_OK; 1308 } 1309 if (ret != NETDEV_TX_OK) { 1310 info->control.vif = &sdata->vif; 1311 return IEEE80211_TX_AGAIN; 1312 } 1313 1314 *skbp = skb = next; 1315 ieee80211_led_tx(local, 1); 1316 fragm = true; 1317 } 1318 1319 return IEEE80211_TX_OK; 1320 } 1321 1322 /* 1323 * Invoke TX handlers, return 0 on success and non-zero if the 1324 * frame was dropped or queued. 1325 */ 1326 static int invoke_tx_handlers(struct ieee80211_tx_data *tx) 1327 { 1328 struct sk_buff *skb = tx->skb; 1329 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 1330 ieee80211_tx_result res = TX_DROP; 1331 1332 #define CALL_TXH(txh) \ 1333 do { \ 1334 res = txh(tx); \ 1335 if (res != TX_CONTINUE) \ 1336 goto txh_done; \ 1337 } while (0) 1338 1339 CALL_TXH(ieee80211_tx_h_dynamic_ps); 1340 CALL_TXH(ieee80211_tx_h_check_assoc); 1341 CALL_TXH(ieee80211_tx_h_ps_buf); 1342 CALL_TXH(ieee80211_tx_h_select_key); 1343 if (!(tx->local->hw.flags & IEEE80211_HW_HAS_RATE_CONTROL)) 1344 CALL_TXH(ieee80211_tx_h_rate_ctrl); 1345 1346 if (unlikely(info->flags & IEEE80211_TX_INTFL_RETRANSMISSION)) 1347 goto txh_done; 1348 1349 CALL_TXH(ieee80211_tx_h_michael_mic_add); 1350 CALL_TXH(ieee80211_tx_h_sequence); 1351 CALL_TXH(ieee80211_tx_h_fragment); 1352 /* handlers after fragment must be aware of tx info fragmentation! */ 1353 CALL_TXH(ieee80211_tx_h_stats); 1354 CALL_TXH(ieee80211_tx_h_encrypt); 1355 CALL_TXH(ieee80211_tx_h_calculate_duration); 1356 #undef CALL_TXH 1357 1358 txh_done: 1359 if (unlikely(res == TX_DROP)) { 1360 I802_DEBUG_INC(tx->local->tx_handlers_drop); 1361 while (skb) { 1362 struct sk_buff *next; 1363 1364 next = skb->next; 1365 dev_kfree_skb(skb); 1366 skb = next; 1367 } 1368 return -1; 1369 } else if (unlikely(res == TX_QUEUED)) { 1370 I802_DEBUG_INC(tx->local->tx_handlers_queued); 1371 return -1; 1372 } 1373 1374 return 0; 1375 } 1376 1377 static void ieee80211_tx(struct ieee80211_sub_if_data *sdata, 1378 struct sk_buff *skb, bool txpending) 1379 { 1380 struct ieee80211_local *local = sdata->local; 1381 struct ieee80211_tx_data tx; 1382 ieee80211_tx_result res_prepare; 1383 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 1384 struct sk_buff *next; 1385 unsigned long flags; 1386 int ret, retries; 1387 u16 queue; 1388 1389 queue = skb_get_queue_mapping(skb); 1390 1391 if (unlikely(skb->len < 10)) { 1392 dev_kfree_skb(skb); 1393 return; 1394 } 1395 1396 rcu_read_lock(); 1397 1398 /* initialises tx */ 1399 res_prepare = ieee80211_tx_prepare(sdata, &tx, skb); 1400 1401 if (unlikely(res_prepare == TX_DROP)) { 1402 dev_kfree_skb(skb); 1403 rcu_read_unlock(); 1404 return; 1405 } else if (unlikely(res_prepare == TX_QUEUED)) { 1406 rcu_read_unlock(); 1407 return; 1408 } 1409 1410 tx.channel = local->hw.conf.channel; 1411 info->band = tx.channel->band; 1412 1413 if (invoke_tx_handlers(&tx)) 1414 goto out; 1415 1416 retries = 0; 1417 retry: 1418 ret = __ieee80211_tx(local, &tx.skb, tx.sta, txpending); 1419 switch (ret) { 1420 case IEEE80211_TX_OK: 1421 break; 1422 case IEEE80211_TX_AGAIN: 1423 /* 1424 * Since there are no fragmented frames on A-MPDU 1425 * queues, there's no reason for a driver to reject 1426 * a frame there, warn and drop it. 1427 */ 1428 if (WARN_ON(info->flags & IEEE80211_TX_CTL_AMPDU)) 1429 goto drop; 1430 /* fall through */ 1431 case IEEE80211_TX_PENDING: 1432 skb = tx.skb; 1433 1434 spin_lock_irqsave(&local->queue_stop_reason_lock, flags); 1435 1436 if (local->queue_stop_reasons[queue] || 1437 !skb_queue_empty(&local->pending[queue])) { 1438 /* 1439 * if queue is stopped, queue up frames for later 1440 * transmission from the tasklet 1441 */ 1442 do { 1443 next = skb->next; 1444 skb->next = NULL; 1445 if (unlikely(txpending)) 1446 __skb_queue_head(&local->pending[queue], 1447 skb); 1448 else 1449 __skb_queue_tail(&local->pending[queue], 1450 skb); 1451 } while ((skb = next)); 1452 1453 spin_unlock_irqrestore(&local->queue_stop_reason_lock, 1454 flags); 1455 } else { 1456 /* 1457 * otherwise retry, but this is a race condition or 1458 * a driver bug (which we warn about if it persists) 1459 */ 1460 spin_unlock_irqrestore(&local->queue_stop_reason_lock, 1461 flags); 1462 1463 retries++; 1464 if (WARN(retries > 10, "tx refused but queue active\n")) 1465 goto drop; 1466 goto retry; 1467 } 1468 } 1469 out: 1470 rcu_read_unlock(); 1471 return; 1472 1473 drop: 1474 rcu_read_unlock(); 1475 1476 skb = tx.skb; 1477 while (skb) { 1478 next = skb->next; 1479 dev_kfree_skb(skb); 1480 skb = next; 1481 } 1482 } 1483 1484 /* device xmit handlers */ 1485 1486 static int ieee80211_skb_resize(struct ieee80211_local *local, 1487 struct sk_buff *skb, 1488 int head_need, bool may_encrypt) 1489 { 1490 int tail_need = 0; 1491 1492 /* 1493 * This could be optimised, devices that do full hardware 1494 * crypto (including TKIP MMIC) need no tailroom... But we 1495 * have no drivers for such devices currently. 1496 */ 1497 if (may_encrypt) { 1498 tail_need = IEEE80211_ENCRYPT_TAILROOM; 1499 tail_need -= skb_tailroom(skb); 1500 tail_need = max_t(int, tail_need, 0); 1501 } 1502 1503 if (head_need || tail_need) { 1504 /* Sorry. Can't account for this any more */ 1505 skb_orphan(skb); 1506 } 1507 1508 if (skb_header_cloned(skb)) 1509 I802_DEBUG_INC(local->tx_expand_skb_head_cloned); 1510 else 1511 I802_DEBUG_INC(local->tx_expand_skb_head); 1512 1513 if (pskb_expand_head(skb, head_need, tail_need, GFP_ATOMIC)) { 1514 printk(KERN_DEBUG "%s: failed to reallocate TX buffer\n", 1515 wiphy_name(local->hw.wiphy)); 1516 return -ENOMEM; 1517 } 1518 1519 /* update truesize too */ 1520 skb->truesize += head_need + tail_need; 1521 1522 return 0; 1523 } 1524 1525 static void ieee80211_xmit(struct ieee80211_sub_if_data *sdata, 1526 struct sk_buff *skb) 1527 { 1528 struct ieee80211_local *local = sdata->local; 1529 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 1530 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 1531 struct ieee80211_sub_if_data *tmp_sdata; 1532 int headroom; 1533 bool may_encrypt; 1534 1535 rcu_read_lock(); 1536 1537 if (unlikely(sdata->vif.type == NL80211_IFTYPE_MONITOR)) { 1538 int hdrlen; 1539 u16 len_rthdr; 1540 1541 info->flags |= IEEE80211_TX_CTL_INJECTED | 1542 IEEE80211_TX_INTFL_HAS_RADIOTAP; 1543 1544 len_rthdr = ieee80211_get_radiotap_len(skb->data); 1545 hdr = (struct ieee80211_hdr *)(skb->data + len_rthdr); 1546 hdrlen = ieee80211_hdrlen(hdr->frame_control); 1547 1548 /* check the header is complete in the frame */ 1549 if (likely(skb->len >= len_rthdr + hdrlen)) { 1550 /* 1551 * We process outgoing injected frames that have a 1552 * local address we handle as though they are our 1553 * own frames. 1554 * This code here isn't entirely correct, the local 1555 * MAC address is not necessarily enough to find 1556 * the interface to use; for that proper VLAN/WDS 1557 * support we will need a different mechanism. 1558 */ 1559 1560 list_for_each_entry_rcu(tmp_sdata, &local->interfaces, 1561 list) { 1562 if (!ieee80211_sdata_running(tmp_sdata)) 1563 continue; 1564 if (tmp_sdata->vif.type != NL80211_IFTYPE_AP) 1565 continue; 1566 if (compare_ether_addr(tmp_sdata->vif.addr, 1567 hdr->addr2) == 0) { 1568 sdata = tmp_sdata; 1569 break; 1570 } 1571 } 1572 } 1573 } 1574 1575 may_encrypt = !(info->flags & IEEE80211_TX_INTFL_DONT_ENCRYPT); 1576 1577 headroom = local->tx_headroom; 1578 if (may_encrypt) 1579 headroom += IEEE80211_ENCRYPT_HEADROOM; 1580 headroom -= skb_headroom(skb); 1581 headroom = max_t(int, 0, headroom); 1582 1583 if (ieee80211_skb_resize(local, skb, headroom, may_encrypt)) { 1584 dev_kfree_skb(skb); 1585 rcu_read_unlock(); 1586 return; 1587 } 1588 1589 info->control.vif = &sdata->vif; 1590 1591 if (ieee80211_vif_is_mesh(&sdata->vif) && 1592 ieee80211_is_data(hdr->frame_control) && 1593 !is_multicast_ether_addr(hdr->addr1)) 1594 if (mesh_nexthop_lookup(skb, sdata)) { 1595 /* skb queued: don't free */ 1596 rcu_read_unlock(); 1597 return; 1598 } 1599 1600 ieee80211_set_qos_hdr(local, skb); 1601 ieee80211_tx(sdata, skb, false); 1602 rcu_read_unlock(); 1603 } 1604 1605 netdev_tx_t ieee80211_monitor_start_xmit(struct sk_buff *skb, 1606 struct net_device *dev) 1607 { 1608 struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr); 1609 struct ieee80211_channel *chan = local->hw.conf.channel; 1610 struct ieee80211_radiotap_header *prthdr = 1611 (struct ieee80211_radiotap_header *)skb->data; 1612 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 1613 u16 len_rthdr; 1614 1615 /* 1616 * Frame injection is not allowed if beaconing is not allowed 1617 * or if we need radar detection. Beaconing is usually not allowed when 1618 * the mode or operation (Adhoc, AP, Mesh) does not support DFS. 1619 * Passive scan is also used in world regulatory domains where 1620 * your country is not known and as such it should be treated as 1621 * NO TX unless the channel is explicitly allowed in which case 1622 * your current regulatory domain would not have the passive scan 1623 * flag. 1624 * 1625 * Since AP mode uses monitor interfaces to inject/TX management 1626 * frames we can make AP mode the exception to this rule once it 1627 * supports radar detection as its implementation can deal with 1628 * radar detection by itself. We can do that later by adding a 1629 * monitor flag interfaces used for AP support. 1630 */ 1631 if ((chan->flags & (IEEE80211_CHAN_NO_IBSS | IEEE80211_CHAN_RADAR | 1632 IEEE80211_CHAN_PASSIVE_SCAN))) 1633 goto fail; 1634 1635 /* check for not even having the fixed radiotap header part */ 1636 if (unlikely(skb->len < sizeof(struct ieee80211_radiotap_header))) 1637 goto fail; /* too short to be possibly valid */ 1638 1639 /* is it a header version we can trust to find length from? */ 1640 if (unlikely(prthdr->it_version)) 1641 goto fail; /* only version 0 is supported */ 1642 1643 /* then there must be a radiotap header with a length we can use */ 1644 len_rthdr = ieee80211_get_radiotap_len(skb->data); 1645 1646 /* does the skb contain enough to deliver on the alleged length? */ 1647 if (unlikely(skb->len < len_rthdr)) 1648 goto fail; /* skb too short for claimed rt header extent */ 1649 1650 /* 1651 * fix up the pointers accounting for the radiotap 1652 * header still being in there. We are being given 1653 * a precooked IEEE80211 header so no need for 1654 * normal processing 1655 */ 1656 skb_set_mac_header(skb, len_rthdr); 1657 /* 1658 * these are just fixed to the end of the rt area since we 1659 * don't have any better information and at this point, nobody cares 1660 */ 1661 skb_set_network_header(skb, len_rthdr); 1662 skb_set_transport_header(skb, len_rthdr); 1663 1664 memset(info, 0, sizeof(*info)); 1665 1666 info->flags |= IEEE80211_TX_CTL_REQ_TX_STATUS; 1667 1668 /* pass the radiotap header up to xmit */ 1669 ieee80211_xmit(IEEE80211_DEV_TO_SUB_IF(dev), skb); 1670 return NETDEV_TX_OK; 1671 1672 fail: 1673 dev_kfree_skb(skb); 1674 return NETDEV_TX_OK; /* meaning, we dealt with the skb */ 1675 } 1676 1677 /** 1678 * ieee80211_subif_start_xmit - netif start_xmit function for Ethernet-type 1679 * subinterfaces (wlan#, WDS, and VLAN interfaces) 1680 * @skb: packet to be sent 1681 * @dev: incoming interface 1682 * 1683 * Returns: 0 on success (and frees skb in this case) or 1 on failure (skb will 1684 * not be freed, and caller is responsible for either retrying later or freeing 1685 * skb). 1686 * 1687 * This function takes in an Ethernet header and encapsulates it with suitable 1688 * IEEE 802.11 header based on which interface the packet is coming in. The 1689 * encapsulated packet will then be passed to master interface, wlan#.11, for 1690 * transmission (through low-level driver). 1691 */ 1692 netdev_tx_t ieee80211_subif_start_xmit(struct sk_buff *skb, 1693 struct net_device *dev) 1694 { 1695 struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev); 1696 struct ieee80211_local *local = sdata->local; 1697 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 1698 int ret = NETDEV_TX_BUSY, head_need; 1699 u16 ethertype, hdrlen, meshhdrlen = 0; 1700 __le16 fc; 1701 struct ieee80211_hdr hdr; 1702 struct ieee80211s_hdr mesh_hdr; 1703 const u8 *encaps_data; 1704 int encaps_len, skip_header_bytes; 1705 int nh_pos, h_pos; 1706 struct sta_info *sta = NULL; 1707 u32 sta_flags = 0; 1708 1709 if (unlikely(skb->len < ETH_HLEN)) { 1710 ret = NETDEV_TX_OK; 1711 goto fail; 1712 } 1713 1714 nh_pos = skb_network_header(skb) - skb->data; 1715 h_pos = skb_transport_header(skb) - skb->data; 1716 1717 /* convert Ethernet header to proper 802.11 header (based on 1718 * operation mode) */ 1719 ethertype = (skb->data[12] << 8) | skb->data[13]; 1720 fc = cpu_to_le16(IEEE80211_FTYPE_DATA | IEEE80211_STYPE_DATA); 1721 1722 switch (sdata->vif.type) { 1723 case NL80211_IFTYPE_AP_VLAN: 1724 rcu_read_lock(); 1725 sta = rcu_dereference(sdata->u.vlan.sta); 1726 if (sta) { 1727 fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS); 1728 /* RA TA DA SA */ 1729 memcpy(hdr.addr1, sta->sta.addr, ETH_ALEN); 1730 memcpy(hdr.addr2, sdata->vif.addr, ETH_ALEN); 1731 memcpy(hdr.addr3, skb->data, ETH_ALEN); 1732 memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN); 1733 hdrlen = 30; 1734 sta_flags = get_sta_flags(sta); 1735 } 1736 rcu_read_unlock(); 1737 if (sta) 1738 break; 1739 /* fall through */ 1740 case NL80211_IFTYPE_AP: 1741 fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS); 1742 /* DA BSSID SA */ 1743 memcpy(hdr.addr1, skb->data, ETH_ALEN); 1744 memcpy(hdr.addr2, sdata->vif.addr, ETH_ALEN); 1745 memcpy(hdr.addr3, skb->data + ETH_ALEN, ETH_ALEN); 1746 hdrlen = 24; 1747 break; 1748 case NL80211_IFTYPE_WDS: 1749 fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS); 1750 /* RA TA DA SA */ 1751 memcpy(hdr.addr1, sdata->u.wds.remote_addr, ETH_ALEN); 1752 memcpy(hdr.addr2, sdata->vif.addr, ETH_ALEN); 1753 memcpy(hdr.addr3, skb->data, ETH_ALEN); 1754 memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN); 1755 hdrlen = 30; 1756 break; 1757 #ifdef CONFIG_MAC80211_MESH 1758 case NL80211_IFTYPE_MESH_POINT: 1759 if (!sdata->u.mesh.mshcfg.dot11MeshTTL) { 1760 /* Do not send frames with mesh_ttl == 0 */ 1761 sdata->u.mesh.mshstats.dropped_frames_ttl++; 1762 ret = NETDEV_TX_OK; 1763 goto fail; 1764 } 1765 1766 if (compare_ether_addr(sdata->vif.addr, 1767 skb->data + ETH_ALEN) == 0) { 1768 hdrlen = ieee80211_fill_mesh_addresses(&hdr, &fc, 1769 skb->data, skb->data + ETH_ALEN); 1770 meshhdrlen = ieee80211_new_mesh_header(&mesh_hdr, 1771 sdata, NULL, NULL, NULL); 1772 } else { 1773 /* packet from other interface */ 1774 struct mesh_path *mppath; 1775 int is_mesh_mcast = 1; 1776 const u8 *mesh_da; 1777 1778 rcu_read_lock(); 1779 if (is_multicast_ether_addr(skb->data)) 1780 /* DA TA mSA AE:SA */ 1781 mesh_da = skb->data; 1782 else { 1783 static const u8 bcast[ETH_ALEN] = 1784 { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }; 1785 1786 mppath = mpp_path_lookup(skb->data, sdata); 1787 if (mppath) { 1788 /* RA TA mDA mSA AE:DA SA */ 1789 mesh_da = mppath->mpp; 1790 is_mesh_mcast = 0; 1791 } else { 1792 /* DA TA mSA AE:SA */ 1793 mesh_da = bcast; 1794 } 1795 } 1796 hdrlen = ieee80211_fill_mesh_addresses(&hdr, &fc, 1797 mesh_da, sdata->vif.addr); 1798 rcu_read_unlock(); 1799 if (is_mesh_mcast) 1800 meshhdrlen = 1801 ieee80211_new_mesh_header(&mesh_hdr, 1802 sdata, 1803 skb->data + ETH_ALEN, 1804 NULL, 1805 NULL); 1806 else 1807 meshhdrlen = 1808 ieee80211_new_mesh_header(&mesh_hdr, 1809 sdata, 1810 NULL, 1811 skb->data, 1812 skb->data + ETH_ALEN); 1813 1814 } 1815 break; 1816 #endif 1817 case NL80211_IFTYPE_STATION: 1818 memcpy(hdr.addr1, sdata->u.mgd.bssid, ETH_ALEN); 1819 if (sdata->u.mgd.use_4addr && ethertype != ETH_P_PAE) { 1820 fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS); 1821 /* RA TA DA SA */ 1822 memcpy(hdr.addr2, sdata->vif.addr, ETH_ALEN); 1823 memcpy(hdr.addr3, skb->data, ETH_ALEN); 1824 memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN); 1825 hdrlen = 30; 1826 } else { 1827 fc |= cpu_to_le16(IEEE80211_FCTL_TODS); 1828 /* BSSID SA DA */ 1829 memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN); 1830 memcpy(hdr.addr3, skb->data, ETH_ALEN); 1831 hdrlen = 24; 1832 } 1833 break; 1834 case NL80211_IFTYPE_ADHOC: 1835 /* DA SA BSSID */ 1836 memcpy(hdr.addr1, skb->data, ETH_ALEN); 1837 memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN); 1838 memcpy(hdr.addr3, sdata->u.ibss.bssid, ETH_ALEN); 1839 hdrlen = 24; 1840 break; 1841 default: 1842 ret = NETDEV_TX_OK; 1843 goto fail; 1844 } 1845 1846 /* 1847 * There's no need to try to look up the destination 1848 * if it is a multicast address (which can only happen 1849 * in AP mode) 1850 */ 1851 if (!is_multicast_ether_addr(hdr.addr1)) { 1852 rcu_read_lock(); 1853 sta = sta_info_get(sdata, hdr.addr1); 1854 if (sta) 1855 sta_flags = get_sta_flags(sta); 1856 rcu_read_unlock(); 1857 } 1858 1859 /* receiver and we are QoS enabled, use a QoS type frame */ 1860 if ((sta_flags & WLAN_STA_WME) && local->hw.queues >= 4) { 1861 fc |= cpu_to_le16(IEEE80211_STYPE_QOS_DATA); 1862 hdrlen += 2; 1863 } 1864 1865 /* 1866 * Drop unicast frames to unauthorised stations unless they are 1867 * EAPOL frames from the local station. 1868 */ 1869 if (!ieee80211_vif_is_mesh(&sdata->vif) && 1870 unlikely(!is_multicast_ether_addr(hdr.addr1) && 1871 !(sta_flags & WLAN_STA_AUTHORIZED) && 1872 !(ethertype == ETH_P_PAE && 1873 compare_ether_addr(sdata->vif.addr, 1874 skb->data + ETH_ALEN) == 0))) { 1875 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG 1876 if (net_ratelimit()) 1877 printk(KERN_DEBUG "%s: dropped frame to %pM" 1878 " (unauthorized port)\n", dev->name, 1879 hdr.addr1); 1880 #endif 1881 1882 I802_DEBUG_INC(local->tx_handlers_drop_unauth_port); 1883 1884 ret = NETDEV_TX_OK; 1885 goto fail; 1886 } 1887 1888 hdr.frame_control = fc; 1889 hdr.duration_id = 0; 1890 hdr.seq_ctrl = 0; 1891 1892 skip_header_bytes = ETH_HLEN; 1893 if (ethertype == ETH_P_AARP || ethertype == ETH_P_IPX) { 1894 encaps_data = bridge_tunnel_header; 1895 encaps_len = sizeof(bridge_tunnel_header); 1896 skip_header_bytes -= 2; 1897 } else if (ethertype >= 0x600) { 1898 encaps_data = rfc1042_header; 1899 encaps_len = sizeof(rfc1042_header); 1900 skip_header_bytes -= 2; 1901 } else { 1902 encaps_data = NULL; 1903 encaps_len = 0; 1904 } 1905 1906 skb_pull(skb, skip_header_bytes); 1907 nh_pos -= skip_header_bytes; 1908 h_pos -= skip_header_bytes; 1909 1910 head_need = hdrlen + encaps_len + meshhdrlen - skb_headroom(skb); 1911 1912 /* 1913 * So we need to modify the skb header and hence need a copy of 1914 * that. The head_need variable above doesn't, so far, include 1915 * the needed header space that we don't need right away. If we 1916 * can, then we don't reallocate right now but only after the 1917 * frame arrives at the master device (if it does...) 1918 * 1919 * If we cannot, however, then we will reallocate to include all 1920 * the ever needed space. Also, if we need to reallocate it anyway, 1921 * make it big enough for everything we may ever need. 1922 */ 1923 1924 if (head_need > 0 || skb_cloned(skb)) { 1925 head_need += IEEE80211_ENCRYPT_HEADROOM; 1926 head_need += local->tx_headroom; 1927 head_need = max_t(int, 0, head_need); 1928 if (ieee80211_skb_resize(local, skb, head_need, true)) 1929 goto fail; 1930 } 1931 1932 if (encaps_data) { 1933 memcpy(skb_push(skb, encaps_len), encaps_data, encaps_len); 1934 nh_pos += encaps_len; 1935 h_pos += encaps_len; 1936 } 1937 1938 #ifdef CONFIG_MAC80211_MESH 1939 if (meshhdrlen > 0) { 1940 memcpy(skb_push(skb, meshhdrlen), &mesh_hdr, meshhdrlen); 1941 nh_pos += meshhdrlen; 1942 h_pos += meshhdrlen; 1943 } 1944 #endif 1945 1946 if (ieee80211_is_data_qos(fc)) { 1947 __le16 *qos_control; 1948 1949 qos_control = (__le16*) skb_push(skb, 2); 1950 memcpy(skb_push(skb, hdrlen - 2), &hdr, hdrlen - 2); 1951 /* 1952 * Maybe we could actually set some fields here, for now just 1953 * initialise to zero to indicate no special operation. 1954 */ 1955 *qos_control = 0; 1956 } else 1957 memcpy(skb_push(skb, hdrlen), &hdr, hdrlen); 1958 1959 nh_pos += hdrlen; 1960 h_pos += hdrlen; 1961 1962 dev->stats.tx_packets++; 1963 dev->stats.tx_bytes += skb->len; 1964 1965 /* Update skb pointers to various headers since this modified frame 1966 * is going to go through Linux networking code that may potentially 1967 * need things like pointer to IP header. */ 1968 skb_set_mac_header(skb, 0); 1969 skb_set_network_header(skb, nh_pos); 1970 skb_set_transport_header(skb, h_pos); 1971 1972 memset(info, 0, sizeof(*info)); 1973 1974 dev->trans_start = jiffies; 1975 ieee80211_xmit(sdata, skb); 1976 1977 return NETDEV_TX_OK; 1978 1979 fail: 1980 if (ret == NETDEV_TX_OK) 1981 dev_kfree_skb(skb); 1982 1983 return ret; 1984 } 1985 1986 1987 /* 1988 * ieee80211_clear_tx_pending may not be called in a context where 1989 * it is possible that it packets could come in again. 1990 */ 1991 void ieee80211_clear_tx_pending(struct ieee80211_local *local) 1992 { 1993 int i; 1994 1995 for (i = 0; i < local->hw.queues; i++) 1996 skb_queue_purge(&local->pending[i]); 1997 } 1998 1999 static bool ieee80211_tx_pending_skb(struct ieee80211_local *local, 2000 struct sk_buff *skb) 2001 { 2002 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 2003 struct ieee80211_sub_if_data *sdata; 2004 struct sta_info *sta; 2005 struct ieee80211_hdr *hdr; 2006 int ret; 2007 bool result = true; 2008 2009 sdata = vif_to_sdata(info->control.vif); 2010 2011 if (info->flags & IEEE80211_TX_INTFL_NEED_TXPROCESSING) { 2012 ieee80211_tx(sdata, skb, true); 2013 } else { 2014 hdr = (struct ieee80211_hdr *)skb->data; 2015 sta = sta_info_get(sdata, hdr->addr1); 2016 2017 ret = __ieee80211_tx(local, &skb, sta, true); 2018 if (ret != IEEE80211_TX_OK) 2019 result = false; 2020 } 2021 2022 return result; 2023 } 2024 2025 /* 2026 * Transmit all pending packets. Called from tasklet. 2027 */ 2028 void ieee80211_tx_pending(unsigned long data) 2029 { 2030 struct ieee80211_local *local = (struct ieee80211_local *)data; 2031 struct ieee80211_sub_if_data *sdata; 2032 unsigned long flags; 2033 int i; 2034 bool txok; 2035 2036 rcu_read_lock(); 2037 2038 spin_lock_irqsave(&local->queue_stop_reason_lock, flags); 2039 for (i = 0; i < local->hw.queues; i++) { 2040 /* 2041 * If queue is stopped by something other than due to pending 2042 * frames, or we have no pending frames, proceed to next queue. 2043 */ 2044 if (local->queue_stop_reasons[i] || 2045 skb_queue_empty(&local->pending[i])) 2046 continue; 2047 2048 while (!skb_queue_empty(&local->pending[i])) { 2049 struct sk_buff *skb = __skb_dequeue(&local->pending[i]); 2050 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 2051 2052 if (WARN_ON(!info->control.vif)) { 2053 kfree_skb(skb); 2054 continue; 2055 } 2056 2057 spin_unlock_irqrestore(&local->queue_stop_reason_lock, 2058 flags); 2059 2060 txok = ieee80211_tx_pending_skb(local, skb); 2061 if (!txok) 2062 __skb_queue_head(&local->pending[i], skb); 2063 spin_lock_irqsave(&local->queue_stop_reason_lock, 2064 flags); 2065 if (!txok) 2066 break; 2067 } 2068 2069 if (skb_queue_empty(&local->pending[i])) 2070 list_for_each_entry_rcu(sdata, &local->interfaces, list) 2071 netif_tx_wake_queue( 2072 netdev_get_tx_queue(sdata->dev, i)); 2073 } 2074 spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags); 2075 2076 rcu_read_unlock(); 2077 } 2078 2079 /* functions for drivers to get certain frames */ 2080 2081 static void ieee80211_beacon_add_tim(struct ieee80211_if_ap *bss, 2082 struct sk_buff *skb, 2083 struct beacon_data *beacon) 2084 { 2085 u8 *pos, *tim; 2086 int aid0 = 0; 2087 int i, have_bits = 0, n1, n2; 2088 2089 /* Generate bitmap for TIM only if there are any STAs in power save 2090 * mode. */ 2091 if (atomic_read(&bss->num_sta_ps) > 0) 2092 /* in the hope that this is faster than 2093 * checking byte-for-byte */ 2094 have_bits = !bitmap_empty((unsigned long*)bss->tim, 2095 IEEE80211_MAX_AID+1); 2096 2097 if (bss->dtim_count == 0) 2098 bss->dtim_count = beacon->dtim_period - 1; 2099 else 2100 bss->dtim_count--; 2101 2102 tim = pos = (u8 *) skb_put(skb, 6); 2103 *pos++ = WLAN_EID_TIM; 2104 *pos++ = 4; 2105 *pos++ = bss->dtim_count; 2106 *pos++ = beacon->dtim_period; 2107 2108 if (bss->dtim_count == 0 && !skb_queue_empty(&bss->ps_bc_buf)) 2109 aid0 = 1; 2110 2111 if (have_bits) { 2112 /* Find largest even number N1 so that bits numbered 1 through 2113 * (N1 x 8) - 1 in the bitmap are 0 and number N2 so that bits 2114 * (N2 + 1) x 8 through 2007 are 0. */ 2115 n1 = 0; 2116 for (i = 0; i < IEEE80211_MAX_TIM_LEN; i++) { 2117 if (bss->tim[i]) { 2118 n1 = i & 0xfe; 2119 break; 2120 } 2121 } 2122 n2 = n1; 2123 for (i = IEEE80211_MAX_TIM_LEN - 1; i >= n1; i--) { 2124 if (bss->tim[i]) { 2125 n2 = i; 2126 break; 2127 } 2128 } 2129 2130 /* Bitmap control */ 2131 *pos++ = n1 | aid0; 2132 /* Part Virt Bitmap */ 2133 memcpy(pos, bss->tim + n1, n2 - n1 + 1); 2134 2135 tim[1] = n2 - n1 + 4; 2136 skb_put(skb, n2 - n1); 2137 } else { 2138 *pos++ = aid0; /* Bitmap control */ 2139 *pos++ = 0; /* Part Virt Bitmap */ 2140 } 2141 } 2142 2143 struct sk_buff *ieee80211_beacon_get_tim(struct ieee80211_hw *hw, 2144 struct ieee80211_vif *vif, 2145 u16 *tim_offset, u16 *tim_length) 2146 { 2147 struct ieee80211_local *local = hw_to_local(hw); 2148 struct sk_buff *skb = NULL; 2149 struct ieee80211_tx_info *info; 2150 struct ieee80211_sub_if_data *sdata = NULL; 2151 struct ieee80211_if_ap *ap = NULL; 2152 struct beacon_data *beacon; 2153 struct ieee80211_supported_band *sband; 2154 enum ieee80211_band band = local->hw.conf.channel->band; 2155 struct ieee80211_tx_rate_control txrc; 2156 2157 sband = local->hw.wiphy->bands[band]; 2158 2159 rcu_read_lock(); 2160 2161 sdata = vif_to_sdata(vif); 2162 2163 if (tim_offset) 2164 *tim_offset = 0; 2165 if (tim_length) 2166 *tim_length = 0; 2167 2168 if (sdata->vif.type == NL80211_IFTYPE_AP) { 2169 ap = &sdata->u.ap; 2170 beacon = rcu_dereference(ap->beacon); 2171 if (ap && beacon) { 2172 /* 2173 * headroom, head length, 2174 * tail length and maximum TIM length 2175 */ 2176 skb = dev_alloc_skb(local->tx_headroom + 2177 beacon->head_len + 2178 beacon->tail_len + 256); 2179 if (!skb) 2180 goto out; 2181 2182 skb_reserve(skb, local->tx_headroom); 2183 memcpy(skb_put(skb, beacon->head_len), beacon->head, 2184 beacon->head_len); 2185 2186 /* 2187 * Not very nice, but we want to allow the driver to call 2188 * ieee80211_beacon_get() as a response to the set_tim() 2189 * callback. That, however, is already invoked under the 2190 * sta_lock to guarantee consistent and race-free update 2191 * of the tim bitmap in mac80211 and the driver. 2192 */ 2193 if (local->tim_in_locked_section) { 2194 ieee80211_beacon_add_tim(ap, skb, beacon); 2195 } else { 2196 unsigned long flags; 2197 2198 spin_lock_irqsave(&local->sta_lock, flags); 2199 ieee80211_beacon_add_tim(ap, skb, beacon); 2200 spin_unlock_irqrestore(&local->sta_lock, flags); 2201 } 2202 2203 if (tim_offset) 2204 *tim_offset = beacon->head_len; 2205 if (tim_length) 2206 *tim_length = skb->len - beacon->head_len; 2207 2208 if (beacon->tail) 2209 memcpy(skb_put(skb, beacon->tail_len), 2210 beacon->tail, beacon->tail_len); 2211 } else 2212 goto out; 2213 } else if (sdata->vif.type == NL80211_IFTYPE_ADHOC) { 2214 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 2215 struct ieee80211_hdr *hdr; 2216 struct sk_buff *presp = rcu_dereference(ifibss->presp); 2217 2218 if (!presp) 2219 goto out; 2220 2221 skb = skb_copy(presp, GFP_ATOMIC); 2222 if (!skb) 2223 goto out; 2224 2225 hdr = (struct ieee80211_hdr *) skb->data; 2226 hdr->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 2227 IEEE80211_STYPE_BEACON); 2228 } else if (ieee80211_vif_is_mesh(&sdata->vif)) { 2229 struct ieee80211_mgmt *mgmt; 2230 u8 *pos; 2231 2232 /* headroom, head length, tail length and maximum TIM length */ 2233 skb = dev_alloc_skb(local->tx_headroom + 400); 2234 if (!skb) 2235 goto out; 2236 2237 skb_reserve(skb, local->hw.extra_tx_headroom); 2238 mgmt = (struct ieee80211_mgmt *) 2239 skb_put(skb, 24 + sizeof(mgmt->u.beacon)); 2240 memset(mgmt, 0, 24 + sizeof(mgmt->u.beacon)); 2241 mgmt->frame_control = 2242 cpu_to_le16(IEEE80211_FTYPE_MGMT | IEEE80211_STYPE_BEACON); 2243 memset(mgmt->da, 0xff, ETH_ALEN); 2244 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN); 2245 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN); 2246 mgmt->u.beacon.beacon_int = 2247 cpu_to_le16(sdata->vif.bss_conf.beacon_int); 2248 mgmt->u.beacon.capab_info = 0x0; /* 0x0 for MPs */ 2249 2250 pos = skb_put(skb, 2); 2251 *pos++ = WLAN_EID_SSID; 2252 *pos++ = 0x0; 2253 2254 mesh_mgmt_ies_add(skb, sdata); 2255 } else { 2256 WARN_ON(1); 2257 goto out; 2258 } 2259 2260 info = IEEE80211_SKB_CB(skb); 2261 2262 info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT; 2263 info->flags |= IEEE80211_TX_CTL_NO_ACK; 2264 info->band = band; 2265 2266 memset(&txrc, 0, sizeof(txrc)); 2267 txrc.hw = hw; 2268 txrc.sband = sband; 2269 txrc.bss_conf = &sdata->vif.bss_conf; 2270 txrc.skb = skb; 2271 txrc.reported_rate.idx = -1; 2272 txrc.rate_idx_mask = sdata->rc_rateidx_mask[band]; 2273 if (txrc.rate_idx_mask == (1 << sband->n_bitrates) - 1) 2274 txrc.max_rate_idx = -1; 2275 else 2276 txrc.max_rate_idx = fls(txrc.rate_idx_mask) - 1; 2277 txrc.ap = true; 2278 rate_control_get_rate(sdata, NULL, &txrc); 2279 2280 info->control.vif = vif; 2281 2282 info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT | 2283 IEEE80211_TX_CTL_ASSIGN_SEQ | 2284 IEEE80211_TX_CTL_FIRST_FRAGMENT; 2285 out: 2286 rcu_read_unlock(); 2287 return skb; 2288 } 2289 EXPORT_SYMBOL(ieee80211_beacon_get_tim); 2290 2291 struct sk_buff *ieee80211_pspoll_get(struct ieee80211_hw *hw, 2292 struct ieee80211_vif *vif) 2293 { 2294 struct ieee80211_sub_if_data *sdata; 2295 struct ieee80211_if_managed *ifmgd; 2296 struct ieee80211_pspoll *pspoll; 2297 struct ieee80211_local *local; 2298 struct sk_buff *skb; 2299 2300 if (WARN_ON(vif->type != NL80211_IFTYPE_STATION)) 2301 return NULL; 2302 2303 sdata = vif_to_sdata(vif); 2304 ifmgd = &sdata->u.mgd; 2305 local = sdata->local; 2306 2307 skb = dev_alloc_skb(local->hw.extra_tx_headroom + sizeof(*pspoll)); 2308 if (!skb) { 2309 printk(KERN_DEBUG "%s: failed to allocate buffer for " 2310 "pspoll template\n", sdata->name); 2311 return NULL; 2312 } 2313 skb_reserve(skb, local->hw.extra_tx_headroom); 2314 2315 pspoll = (struct ieee80211_pspoll *) skb_put(skb, sizeof(*pspoll)); 2316 memset(pspoll, 0, sizeof(*pspoll)); 2317 pspoll->frame_control = cpu_to_le16(IEEE80211_FTYPE_CTL | 2318 IEEE80211_STYPE_PSPOLL); 2319 pspoll->aid = cpu_to_le16(ifmgd->aid); 2320 2321 /* aid in PS-Poll has its two MSBs each set to 1 */ 2322 pspoll->aid |= cpu_to_le16(1 << 15 | 1 << 14); 2323 2324 memcpy(pspoll->bssid, ifmgd->bssid, ETH_ALEN); 2325 memcpy(pspoll->ta, vif->addr, ETH_ALEN); 2326 2327 return skb; 2328 } 2329 EXPORT_SYMBOL(ieee80211_pspoll_get); 2330 2331 struct sk_buff *ieee80211_nullfunc_get(struct ieee80211_hw *hw, 2332 struct ieee80211_vif *vif) 2333 { 2334 struct ieee80211_hdr_3addr *nullfunc; 2335 struct ieee80211_sub_if_data *sdata; 2336 struct ieee80211_if_managed *ifmgd; 2337 struct ieee80211_local *local; 2338 struct sk_buff *skb; 2339 2340 if (WARN_ON(vif->type != NL80211_IFTYPE_STATION)) 2341 return NULL; 2342 2343 sdata = vif_to_sdata(vif); 2344 ifmgd = &sdata->u.mgd; 2345 local = sdata->local; 2346 2347 skb = dev_alloc_skb(local->hw.extra_tx_headroom + sizeof(*nullfunc)); 2348 if (!skb) { 2349 printk(KERN_DEBUG "%s: failed to allocate buffer for nullfunc " 2350 "template\n", sdata->name); 2351 return NULL; 2352 } 2353 skb_reserve(skb, local->hw.extra_tx_headroom); 2354 2355 nullfunc = (struct ieee80211_hdr_3addr *) skb_put(skb, 2356 sizeof(*nullfunc)); 2357 memset(nullfunc, 0, sizeof(*nullfunc)); 2358 nullfunc->frame_control = cpu_to_le16(IEEE80211_FTYPE_DATA | 2359 IEEE80211_STYPE_NULLFUNC | 2360 IEEE80211_FCTL_TODS); 2361 memcpy(nullfunc->addr1, ifmgd->bssid, ETH_ALEN); 2362 memcpy(nullfunc->addr2, vif->addr, ETH_ALEN); 2363 memcpy(nullfunc->addr3, ifmgd->bssid, ETH_ALEN); 2364 2365 return skb; 2366 } 2367 EXPORT_SYMBOL(ieee80211_nullfunc_get); 2368 2369 struct sk_buff *ieee80211_probereq_get(struct ieee80211_hw *hw, 2370 struct ieee80211_vif *vif, 2371 const u8 *ssid, size_t ssid_len, 2372 const u8 *ie, size_t ie_len) 2373 { 2374 struct ieee80211_sub_if_data *sdata; 2375 struct ieee80211_local *local; 2376 struct ieee80211_hdr_3addr *hdr; 2377 struct sk_buff *skb; 2378 size_t ie_ssid_len; 2379 u8 *pos; 2380 2381 sdata = vif_to_sdata(vif); 2382 local = sdata->local; 2383 ie_ssid_len = 2 + ssid_len; 2384 2385 skb = dev_alloc_skb(local->hw.extra_tx_headroom + sizeof(*hdr) + 2386 ie_ssid_len + ie_len); 2387 if (!skb) { 2388 printk(KERN_DEBUG "%s: failed to allocate buffer for probe " 2389 "request template\n", sdata->name); 2390 return NULL; 2391 } 2392 2393 skb_reserve(skb, local->hw.extra_tx_headroom); 2394 2395 hdr = (struct ieee80211_hdr_3addr *) skb_put(skb, sizeof(*hdr)); 2396 memset(hdr, 0, sizeof(*hdr)); 2397 hdr->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 2398 IEEE80211_STYPE_PROBE_REQ); 2399 memset(hdr->addr1, 0xff, ETH_ALEN); 2400 memcpy(hdr->addr2, vif->addr, ETH_ALEN); 2401 memset(hdr->addr3, 0xff, ETH_ALEN); 2402 2403 pos = skb_put(skb, ie_ssid_len); 2404 *pos++ = WLAN_EID_SSID; 2405 *pos++ = ssid_len; 2406 if (ssid) 2407 memcpy(pos, ssid, ssid_len); 2408 pos += ssid_len; 2409 2410 if (ie) { 2411 pos = skb_put(skb, ie_len); 2412 memcpy(pos, ie, ie_len); 2413 } 2414 2415 return skb; 2416 } 2417 EXPORT_SYMBOL(ieee80211_probereq_get); 2418 2419 void ieee80211_rts_get(struct ieee80211_hw *hw, struct ieee80211_vif *vif, 2420 const void *frame, size_t frame_len, 2421 const struct ieee80211_tx_info *frame_txctl, 2422 struct ieee80211_rts *rts) 2423 { 2424 const struct ieee80211_hdr *hdr = frame; 2425 2426 rts->frame_control = 2427 cpu_to_le16(IEEE80211_FTYPE_CTL | IEEE80211_STYPE_RTS); 2428 rts->duration = ieee80211_rts_duration(hw, vif, frame_len, 2429 frame_txctl); 2430 memcpy(rts->ra, hdr->addr1, sizeof(rts->ra)); 2431 memcpy(rts->ta, hdr->addr2, sizeof(rts->ta)); 2432 } 2433 EXPORT_SYMBOL(ieee80211_rts_get); 2434 2435 void ieee80211_ctstoself_get(struct ieee80211_hw *hw, struct ieee80211_vif *vif, 2436 const void *frame, size_t frame_len, 2437 const struct ieee80211_tx_info *frame_txctl, 2438 struct ieee80211_cts *cts) 2439 { 2440 const struct ieee80211_hdr *hdr = frame; 2441 2442 cts->frame_control = 2443 cpu_to_le16(IEEE80211_FTYPE_CTL | IEEE80211_STYPE_CTS); 2444 cts->duration = ieee80211_ctstoself_duration(hw, vif, 2445 frame_len, frame_txctl); 2446 memcpy(cts->ra, hdr->addr1, sizeof(cts->ra)); 2447 } 2448 EXPORT_SYMBOL(ieee80211_ctstoself_get); 2449 2450 struct sk_buff * 2451 ieee80211_get_buffered_bc(struct ieee80211_hw *hw, 2452 struct ieee80211_vif *vif) 2453 { 2454 struct ieee80211_local *local = hw_to_local(hw); 2455 struct sk_buff *skb = NULL; 2456 struct sta_info *sta; 2457 struct ieee80211_tx_data tx; 2458 struct ieee80211_sub_if_data *sdata; 2459 struct ieee80211_if_ap *bss = NULL; 2460 struct beacon_data *beacon; 2461 struct ieee80211_tx_info *info; 2462 2463 sdata = vif_to_sdata(vif); 2464 bss = &sdata->u.ap; 2465 2466 rcu_read_lock(); 2467 beacon = rcu_dereference(bss->beacon); 2468 2469 if (sdata->vif.type != NL80211_IFTYPE_AP || !beacon || !beacon->head) 2470 goto out; 2471 2472 if (bss->dtim_count != 0) 2473 goto out; /* send buffered bc/mc only after DTIM beacon */ 2474 2475 while (1) { 2476 skb = skb_dequeue(&bss->ps_bc_buf); 2477 if (!skb) 2478 goto out; 2479 local->total_ps_buffered--; 2480 2481 if (!skb_queue_empty(&bss->ps_bc_buf) && skb->len >= 2) { 2482 struct ieee80211_hdr *hdr = 2483 (struct ieee80211_hdr *) skb->data; 2484 /* more buffered multicast/broadcast frames ==> set 2485 * MoreData flag in IEEE 802.11 header to inform PS 2486 * STAs */ 2487 hdr->frame_control |= 2488 cpu_to_le16(IEEE80211_FCTL_MOREDATA); 2489 } 2490 2491 if (!ieee80211_tx_prepare(sdata, &tx, skb)) 2492 break; 2493 dev_kfree_skb_any(skb); 2494 } 2495 2496 info = IEEE80211_SKB_CB(skb); 2497 2498 sta = tx.sta; 2499 tx.flags |= IEEE80211_TX_PS_BUFFERED; 2500 tx.channel = local->hw.conf.channel; 2501 info->band = tx.channel->band; 2502 2503 if (invoke_tx_handlers(&tx)) 2504 skb = NULL; 2505 out: 2506 rcu_read_unlock(); 2507 2508 return skb; 2509 } 2510 EXPORT_SYMBOL(ieee80211_get_buffered_bc); 2511 2512 void ieee80211_tx_skb(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb) 2513 { 2514 skb_set_mac_header(skb, 0); 2515 skb_set_network_header(skb, 0); 2516 skb_set_transport_header(skb, 0); 2517 2518 /* send all internal mgmt frames on VO */ 2519 skb_set_queue_mapping(skb, 0); 2520 2521 /* 2522 * The other path calling ieee80211_xmit is from the tasklet, 2523 * and while we can handle concurrent transmissions locking 2524 * requirements are that we do not come into tx with bhs on. 2525 */ 2526 local_bh_disable(); 2527 ieee80211_xmit(sdata, skb); 2528 local_bh_enable(); 2529 } 2530