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 */ 183 184 static ieee80211_tx_result debug_noinline 185 ieee80211_tx_h_check_assoc(struct ieee80211_tx_data *tx) 186 { 187 188 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data; 189 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb); 190 u32 sta_flags; 191 192 if (unlikely(info->flags & IEEE80211_TX_CTL_INJECTED)) 193 return TX_CONTINUE; 194 195 if (unlikely(test_bit(SCAN_OFF_CHANNEL, &tx->local->scanning)) && 196 !ieee80211_is_probe_req(hdr->frame_control) && 197 !ieee80211_is_nullfunc(hdr->frame_control)) 198 /* 199 * When software scanning only nullfunc frames (to notify 200 * the sleep state to the AP) and probe requests (for the 201 * active scan) are allowed, all other frames should not be 202 * sent and we should not get here, but if we do 203 * nonetheless, drop them to avoid sending them 204 * off-channel. See the link below and 205 * ieee80211_start_scan() for more. 206 * 207 * http://article.gmane.org/gmane.linux.kernel.wireless.general/30089 208 */ 209 return TX_DROP; 210 211 if (tx->sdata->vif.type == NL80211_IFTYPE_MESH_POINT) 212 return TX_CONTINUE; 213 214 if (tx->flags & IEEE80211_TX_PS_BUFFERED) 215 return TX_CONTINUE; 216 217 sta_flags = tx->sta ? get_sta_flags(tx->sta) : 0; 218 219 if (likely(tx->flags & IEEE80211_TX_UNICAST)) { 220 if (unlikely(!(sta_flags & WLAN_STA_ASSOC) && 221 tx->sdata->vif.type != NL80211_IFTYPE_ADHOC && 222 ieee80211_is_data(hdr->frame_control))) { 223 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG 224 printk(KERN_DEBUG "%s: dropped data frame to not " 225 "associated station %pM\n", 226 tx->dev->name, hdr->addr1); 227 #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */ 228 I802_DEBUG_INC(tx->local->tx_handlers_drop_not_assoc); 229 return TX_DROP; 230 } 231 } else { 232 if (unlikely(ieee80211_is_data(hdr->frame_control) && 233 tx->local->num_sta == 0 && 234 tx->sdata->vif.type != NL80211_IFTYPE_ADHOC)) { 235 /* 236 * No associated STAs - no need to send multicast 237 * frames. 238 */ 239 return TX_DROP; 240 } 241 return TX_CONTINUE; 242 } 243 244 return TX_CONTINUE; 245 } 246 247 /* This function is called whenever the AP is about to exceed the maximum limit 248 * of buffered frames for power saving STAs. This situation should not really 249 * happen often during normal operation, so dropping the oldest buffered packet 250 * from each queue should be OK to make some room for new frames. */ 251 static void purge_old_ps_buffers(struct ieee80211_local *local) 252 { 253 int total = 0, purged = 0; 254 struct sk_buff *skb; 255 struct ieee80211_sub_if_data *sdata; 256 struct sta_info *sta; 257 258 /* 259 * virtual interfaces are protected by RCU 260 */ 261 rcu_read_lock(); 262 263 list_for_each_entry_rcu(sdata, &local->interfaces, list) { 264 struct ieee80211_if_ap *ap; 265 if (sdata->vif.type != NL80211_IFTYPE_AP) 266 continue; 267 ap = &sdata->u.ap; 268 skb = skb_dequeue(&ap->ps_bc_buf); 269 if (skb) { 270 purged++; 271 dev_kfree_skb(skb); 272 } 273 total += skb_queue_len(&ap->ps_bc_buf); 274 } 275 276 list_for_each_entry_rcu(sta, &local->sta_list, list) { 277 skb = skb_dequeue(&sta->ps_tx_buf); 278 if (skb) { 279 purged++; 280 dev_kfree_skb(skb); 281 } 282 total += skb_queue_len(&sta->ps_tx_buf); 283 } 284 285 rcu_read_unlock(); 286 287 local->total_ps_buffered = total; 288 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 289 printk(KERN_DEBUG "%s: PS buffers full - purged %d frames\n", 290 wiphy_name(local->hw.wiphy), purged); 291 #endif 292 } 293 294 static ieee80211_tx_result 295 ieee80211_tx_h_multicast_ps_buf(struct ieee80211_tx_data *tx) 296 { 297 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb); 298 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data; 299 300 /* 301 * broadcast/multicast frame 302 * 303 * If any of the associated stations is in power save mode, 304 * the frame is buffered to be sent after DTIM beacon frame. 305 * This is done either by the hardware or us. 306 */ 307 308 /* powersaving STAs only in AP/VLAN mode */ 309 if (!tx->sdata->bss) 310 return TX_CONTINUE; 311 312 /* no buffering for ordered frames */ 313 if (ieee80211_has_order(hdr->frame_control)) 314 return TX_CONTINUE; 315 316 /* no stations in PS mode */ 317 if (!atomic_read(&tx->sdata->bss->num_sta_ps)) 318 return TX_CONTINUE; 319 320 /* buffered in hardware */ 321 if (!(tx->local->hw.flags & IEEE80211_HW_HOST_BROADCAST_PS_BUFFERING)) { 322 info->flags |= IEEE80211_TX_CTL_SEND_AFTER_DTIM; 323 324 return TX_CONTINUE; 325 } 326 327 /* buffered in mac80211 */ 328 if (tx->local->total_ps_buffered >= TOTAL_MAX_TX_BUFFER) 329 purge_old_ps_buffers(tx->local); 330 331 if (skb_queue_len(&tx->sdata->bss->ps_bc_buf) >= AP_MAX_BC_BUFFER) { 332 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 333 if (net_ratelimit()) 334 printk(KERN_DEBUG "%s: BC TX buffer full - dropping the oldest frame\n", 335 tx->dev->name); 336 #endif 337 dev_kfree_skb(skb_dequeue(&tx->sdata->bss->ps_bc_buf)); 338 } else 339 tx->local->total_ps_buffered++; 340 341 skb_queue_tail(&tx->sdata->bss->ps_bc_buf, tx->skb); 342 343 return TX_QUEUED; 344 } 345 346 static int ieee80211_use_mfp(__le16 fc, struct sta_info *sta, 347 struct sk_buff *skb) 348 { 349 if (!ieee80211_is_mgmt(fc)) 350 return 0; 351 352 if (sta == NULL || !test_sta_flags(sta, WLAN_STA_MFP)) 353 return 0; 354 355 if (!ieee80211_is_robust_mgmt_frame((struct ieee80211_hdr *) 356 skb->data)) 357 return 0; 358 359 return 1; 360 } 361 362 static ieee80211_tx_result 363 ieee80211_tx_h_unicast_ps_buf(struct ieee80211_tx_data *tx) 364 { 365 struct sta_info *sta = tx->sta; 366 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb); 367 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data; 368 u32 staflags; 369 370 if (unlikely(!sta || ieee80211_is_probe_resp(hdr->frame_control))) 371 return TX_CONTINUE; 372 373 staflags = get_sta_flags(sta); 374 375 if (unlikely((staflags & WLAN_STA_PS) && 376 !(info->flags & IEEE80211_TX_CTL_PSPOLL_RESPONSE))) { 377 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 378 printk(KERN_DEBUG "STA %pM aid %d: PS buffer (entries " 379 "before %d)\n", 380 sta->sta.addr, sta->sta.aid, 381 skb_queue_len(&sta->ps_tx_buf)); 382 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 383 if (tx->local->total_ps_buffered >= TOTAL_MAX_TX_BUFFER) 384 purge_old_ps_buffers(tx->local); 385 if (skb_queue_len(&sta->ps_tx_buf) >= STA_MAX_TX_BUFFER) { 386 struct sk_buff *old = skb_dequeue(&sta->ps_tx_buf); 387 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 388 if (net_ratelimit()) { 389 printk(KERN_DEBUG "%s: STA %pM TX " 390 "buffer full - dropping oldest frame\n", 391 tx->dev->name, sta->sta.addr); 392 } 393 #endif 394 dev_kfree_skb(old); 395 } else 396 tx->local->total_ps_buffered++; 397 398 /* Queue frame to be sent after STA sends an PS Poll frame */ 399 if (skb_queue_empty(&sta->ps_tx_buf)) 400 sta_info_set_tim_bit(sta); 401 402 info->control.jiffies = jiffies; 403 info->control.vif = &tx->sdata->vif; 404 info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING; 405 skb_queue_tail(&sta->ps_tx_buf, tx->skb); 406 return TX_QUEUED; 407 } 408 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 409 else if (unlikely(test_sta_flags(sta, WLAN_STA_PS))) { 410 printk(KERN_DEBUG "%s: STA %pM in PS mode, but pspoll " 411 "set -> send frame\n", tx->dev->name, 412 sta->sta.addr); 413 } 414 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 415 416 return TX_CONTINUE; 417 } 418 419 static ieee80211_tx_result debug_noinline 420 ieee80211_tx_h_ps_buf(struct ieee80211_tx_data *tx) 421 { 422 if (unlikely(tx->flags & IEEE80211_TX_PS_BUFFERED)) 423 return TX_CONTINUE; 424 425 if (tx->flags & IEEE80211_TX_UNICAST) 426 return ieee80211_tx_h_unicast_ps_buf(tx); 427 else 428 return ieee80211_tx_h_multicast_ps_buf(tx); 429 } 430 431 static ieee80211_tx_result debug_noinline 432 ieee80211_tx_h_select_key(struct ieee80211_tx_data *tx) 433 { 434 struct ieee80211_key *key = NULL; 435 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb); 436 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data; 437 438 if (unlikely(info->flags & IEEE80211_TX_INTFL_DONT_ENCRYPT)) 439 tx->key = NULL; 440 else if (tx->sta && (key = rcu_dereference(tx->sta->key))) 441 tx->key = key; 442 else if (ieee80211_is_mgmt(hdr->frame_control) && 443 (key = rcu_dereference(tx->sdata->default_mgmt_key))) 444 tx->key = key; 445 else if ((key = rcu_dereference(tx->sdata->default_key))) 446 tx->key = key; 447 else if (tx->sdata->drop_unencrypted && 448 (tx->skb->protocol != cpu_to_be16(ETH_P_PAE)) && 449 !(info->flags & IEEE80211_TX_CTL_INJECTED) && 450 (!ieee80211_is_robust_mgmt_frame(hdr) || 451 (ieee80211_is_action(hdr->frame_control) && 452 tx->sta && test_sta_flags(tx->sta, WLAN_STA_MFP)))) { 453 I802_DEBUG_INC(tx->local->tx_handlers_drop_unencrypted); 454 return TX_DROP; 455 } else 456 tx->key = NULL; 457 458 if (tx->key) { 459 tx->key->tx_rx_count++; 460 /* TODO: add threshold stuff again */ 461 462 switch (tx->key->conf.alg) { 463 case ALG_WEP: 464 if (ieee80211_is_auth(hdr->frame_control)) 465 break; 466 case ALG_TKIP: 467 if (!ieee80211_is_data_present(hdr->frame_control)) 468 tx->key = NULL; 469 break; 470 case ALG_CCMP: 471 if (!ieee80211_is_data_present(hdr->frame_control) && 472 !ieee80211_use_mfp(hdr->frame_control, tx->sta, 473 tx->skb)) 474 tx->key = NULL; 475 break; 476 case ALG_AES_CMAC: 477 if (!ieee80211_is_mgmt(hdr->frame_control)) 478 tx->key = NULL; 479 break; 480 } 481 } 482 483 if (!tx->key || !(tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE)) 484 info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT; 485 486 return TX_CONTINUE; 487 } 488 489 static ieee80211_tx_result debug_noinline 490 ieee80211_tx_h_rate_ctrl(struct ieee80211_tx_data *tx) 491 { 492 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb); 493 struct ieee80211_hdr *hdr = (void *)tx->skb->data; 494 struct ieee80211_supported_band *sband; 495 struct ieee80211_rate *rate; 496 int i, len; 497 bool inval = false, rts = false, short_preamble = false; 498 struct ieee80211_tx_rate_control txrc; 499 u32 sta_flags; 500 501 memset(&txrc, 0, sizeof(txrc)); 502 503 sband = tx->local->hw.wiphy->bands[tx->channel->band]; 504 505 len = min_t(int, tx->skb->len + FCS_LEN, 506 tx->local->hw.wiphy->frag_threshold); 507 508 /* set up the tx rate control struct we give the RC algo */ 509 txrc.hw = local_to_hw(tx->local); 510 txrc.sband = sband; 511 txrc.bss_conf = &tx->sdata->vif.bss_conf; 512 txrc.skb = tx->skb; 513 txrc.reported_rate.idx = -1; 514 txrc.max_rate_idx = tx->sdata->max_ratectrl_rateidx; 515 516 /* set up RTS protection if desired */ 517 if (len > tx->local->hw.wiphy->rts_threshold) { 518 txrc.rts = rts = true; 519 } 520 521 /* 522 * Use short preamble if the BSS can handle it, but not for 523 * management frames unless we know the receiver can handle 524 * that -- the management frame might be to a station that 525 * just wants a probe response. 526 */ 527 if (tx->sdata->vif.bss_conf.use_short_preamble && 528 (ieee80211_is_data(hdr->frame_control) || 529 (tx->sta && test_sta_flags(tx->sta, WLAN_STA_SHORT_PREAMBLE)))) 530 txrc.short_preamble = short_preamble = true; 531 532 sta_flags = tx->sta ? get_sta_flags(tx->sta) : 0; 533 534 /* 535 * Lets not bother rate control if we're associated and cannot 536 * talk to the sta. This should not happen. 537 */ 538 if (WARN(test_bit(SCAN_SW_SCANNING, &tx->local->scanning) && 539 (sta_flags & WLAN_STA_ASSOC) && 540 !rate_usable_index_exists(sband, &tx->sta->sta), 541 "%s: Dropped data frame as no usable bitrate found while " 542 "scanning and associated. Target station: " 543 "%pM on %d GHz band\n", 544 tx->dev->name, hdr->addr1, 545 tx->channel->band ? 5 : 2)) 546 return TX_DROP; 547 548 /* 549 * If we're associated with the sta at this point we know we can at 550 * least send the frame at the lowest bit rate. 551 */ 552 rate_control_get_rate(tx->sdata, tx->sta, &txrc); 553 554 if (unlikely(info->control.rates[0].idx < 0)) 555 return TX_DROP; 556 557 if (txrc.reported_rate.idx < 0) 558 txrc.reported_rate = info->control.rates[0]; 559 560 if (tx->sta) 561 tx->sta->last_tx_rate = txrc.reported_rate; 562 563 if (unlikely(!info->control.rates[0].count)) 564 info->control.rates[0].count = 1; 565 566 if (WARN_ON_ONCE((info->control.rates[0].count > 1) && 567 (info->flags & IEEE80211_TX_CTL_NO_ACK))) 568 info->control.rates[0].count = 1; 569 570 if (is_multicast_ether_addr(hdr->addr1)) { 571 /* 572 * XXX: verify the rate is in the basic rateset 573 */ 574 return TX_CONTINUE; 575 } 576 577 /* 578 * set up the RTS/CTS rate as the fastest basic rate 579 * that is not faster than the data rate 580 * 581 * XXX: Should this check all retry rates? 582 */ 583 if (!(info->control.rates[0].flags & IEEE80211_TX_RC_MCS)) { 584 s8 baserate = 0; 585 586 rate = &sband->bitrates[info->control.rates[0].idx]; 587 588 for (i = 0; i < sband->n_bitrates; i++) { 589 /* must be a basic rate */ 590 if (!(tx->sdata->vif.bss_conf.basic_rates & BIT(i))) 591 continue; 592 /* must not be faster than the data rate */ 593 if (sband->bitrates[i].bitrate > rate->bitrate) 594 continue; 595 /* maximum */ 596 if (sband->bitrates[baserate].bitrate < 597 sband->bitrates[i].bitrate) 598 baserate = i; 599 } 600 601 info->control.rts_cts_rate_idx = baserate; 602 } 603 604 for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) { 605 /* 606 * make sure there's no valid rate following 607 * an invalid one, just in case drivers don't 608 * take the API seriously to stop at -1. 609 */ 610 if (inval) { 611 info->control.rates[i].idx = -1; 612 continue; 613 } 614 if (info->control.rates[i].idx < 0) { 615 inval = true; 616 continue; 617 } 618 619 /* 620 * For now assume MCS is already set up correctly, this 621 * needs to be fixed. 622 */ 623 if (info->control.rates[i].flags & IEEE80211_TX_RC_MCS) { 624 WARN_ON(info->control.rates[i].idx > 76); 625 continue; 626 } 627 628 /* set up RTS protection if desired */ 629 if (rts) 630 info->control.rates[i].flags |= 631 IEEE80211_TX_RC_USE_RTS_CTS; 632 633 /* RC is busted */ 634 if (WARN_ON_ONCE(info->control.rates[i].idx >= 635 sband->n_bitrates)) { 636 info->control.rates[i].idx = -1; 637 continue; 638 } 639 640 rate = &sband->bitrates[info->control.rates[i].idx]; 641 642 /* set up short preamble */ 643 if (short_preamble && 644 rate->flags & IEEE80211_RATE_SHORT_PREAMBLE) 645 info->control.rates[i].flags |= 646 IEEE80211_TX_RC_USE_SHORT_PREAMBLE; 647 648 /* set up G protection */ 649 if (!rts && tx->sdata->vif.bss_conf.use_cts_prot && 650 rate->flags & IEEE80211_RATE_ERP_G) 651 info->control.rates[i].flags |= 652 IEEE80211_TX_RC_USE_CTS_PROTECT; 653 } 654 655 return TX_CONTINUE; 656 } 657 658 static ieee80211_tx_result debug_noinline 659 ieee80211_tx_h_misc(struct ieee80211_tx_data *tx) 660 { 661 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb); 662 663 if (tx->sta) 664 info->control.sta = &tx->sta->sta; 665 666 return TX_CONTINUE; 667 } 668 669 static ieee80211_tx_result debug_noinline 670 ieee80211_tx_h_sequence(struct ieee80211_tx_data *tx) 671 { 672 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb); 673 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data; 674 u16 *seq; 675 u8 *qc; 676 int tid; 677 678 /* 679 * Packet injection may want to control the sequence 680 * number, if we have no matching interface then we 681 * neither assign one ourselves nor ask the driver to. 682 */ 683 if (unlikely(info->control.vif->type == NL80211_IFTYPE_MONITOR)) 684 return TX_CONTINUE; 685 686 if (unlikely(ieee80211_is_ctl(hdr->frame_control))) 687 return TX_CONTINUE; 688 689 if (ieee80211_hdrlen(hdr->frame_control) < 24) 690 return TX_CONTINUE; 691 692 /* 693 * Anything but QoS data that has a sequence number field 694 * (is long enough) gets a sequence number from the global 695 * counter. 696 */ 697 if (!ieee80211_is_data_qos(hdr->frame_control)) { 698 /* driver should assign sequence number */ 699 info->flags |= IEEE80211_TX_CTL_ASSIGN_SEQ; 700 /* for pure STA mode without beacons, we can do it */ 701 hdr->seq_ctrl = cpu_to_le16(tx->sdata->sequence_number); 702 tx->sdata->sequence_number += 0x10; 703 return TX_CONTINUE; 704 } 705 706 /* 707 * This should be true for injected/management frames only, for 708 * management frames we have set the IEEE80211_TX_CTL_ASSIGN_SEQ 709 * above since they are not QoS-data frames. 710 */ 711 if (!tx->sta) 712 return TX_CONTINUE; 713 714 /* include per-STA, per-TID sequence counter */ 715 716 qc = ieee80211_get_qos_ctl(hdr); 717 tid = *qc & IEEE80211_QOS_CTL_TID_MASK; 718 seq = &tx->sta->tid_seq[tid]; 719 720 hdr->seq_ctrl = cpu_to_le16(*seq); 721 722 /* Increase the sequence number. */ 723 *seq = (*seq + 0x10) & IEEE80211_SCTL_SEQ; 724 725 return TX_CONTINUE; 726 } 727 728 static int ieee80211_fragment(struct ieee80211_local *local, 729 struct sk_buff *skb, int hdrlen, 730 int frag_threshold) 731 { 732 struct sk_buff *tail = skb, *tmp; 733 int per_fragm = frag_threshold - hdrlen - FCS_LEN; 734 int pos = hdrlen + per_fragm; 735 int rem = skb->len - hdrlen - per_fragm; 736 737 if (WARN_ON(rem < 0)) 738 return -EINVAL; 739 740 while (rem) { 741 int fraglen = per_fragm; 742 743 if (fraglen > rem) 744 fraglen = rem; 745 rem -= fraglen; 746 tmp = dev_alloc_skb(local->tx_headroom + 747 frag_threshold + 748 IEEE80211_ENCRYPT_HEADROOM + 749 IEEE80211_ENCRYPT_TAILROOM); 750 if (!tmp) 751 return -ENOMEM; 752 tail->next = tmp; 753 tail = tmp; 754 skb_reserve(tmp, local->tx_headroom + 755 IEEE80211_ENCRYPT_HEADROOM); 756 /* copy control information */ 757 memcpy(tmp->cb, skb->cb, sizeof(tmp->cb)); 758 skb_copy_queue_mapping(tmp, skb); 759 tmp->priority = skb->priority; 760 tmp->dev = skb->dev; 761 762 /* copy header and data */ 763 memcpy(skb_put(tmp, hdrlen), skb->data, hdrlen); 764 memcpy(skb_put(tmp, fraglen), skb->data + pos, fraglen); 765 766 pos += fraglen; 767 } 768 769 skb->len = hdrlen + per_fragm; 770 return 0; 771 } 772 773 static ieee80211_tx_result debug_noinline 774 ieee80211_tx_h_fragment(struct ieee80211_tx_data *tx) 775 { 776 struct sk_buff *skb = tx->skb; 777 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 778 struct ieee80211_hdr *hdr = (void *)skb->data; 779 int frag_threshold = tx->local->hw.wiphy->frag_threshold; 780 int hdrlen; 781 int fragnum; 782 783 if (!(tx->flags & IEEE80211_TX_FRAGMENTED)) 784 return TX_CONTINUE; 785 786 /* 787 * Warn when submitting a fragmented A-MPDU frame and drop it. 788 * This scenario is handled in ieee80211_tx_prepare but extra 789 * caution taken here as fragmented ampdu may cause Tx stop. 790 */ 791 if (WARN_ON(info->flags & IEEE80211_TX_CTL_AMPDU)) 792 return TX_DROP; 793 794 hdrlen = ieee80211_hdrlen(hdr->frame_control); 795 796 /* internal error, why is TX_FRAGMENTED set? */ 797 if (WARN_ON(skb->len + FCS_LEN <= frag_threshold)) 798 return TX_DROP; 799 800 /* 801 * Now fragment the frame. This will allocate all the fragments and 802 * chain them (using skb as the first fragment) to skb->next. 803 * During transmission, we will remove the successfully transmitted 804 * fragments from this list. When the low-level driver rejects one 805 * of the fragments then we will simply pretend to accept the skb 806 * but store it away as pending. 807 */ 808 if (ieee80211_fragment(tx->local, skb, hdrlen, frag_threshold)) 809 return TX_DROP; 810 811 /* update duration/seq/flags of fragments */ 812 fragnum = 0; 813 do { 814 int next_len; 815 const __le16 morefrags = cpu_to_le16(IEEE80211_FCTL_MOREFRAGS); 816 817 hdr = (void *)skb->data; 818 info = IEEE80211_SKB_CB(skb); 819 820 if (skb->next) { 821 hdr->frame_control |= morefrags; 822 next_len = skb->next->len; 823 /* 824 * No multi-rate retries for fragmented frames, that 825 * would completely throw off the NAV at other STAs. 826 */ 827 info->control.rates[1].idx = -1; 828 info->control.rates[2].idx = -1; 829 info->control.rates[3].idx = -1; 830 info->control.rates[4].idx = -1; 831 BUILD_BUG_ON(IEEE80211_TX_MAX_RATES != 5); 832 info->flags &= ~IEEE80211_TX_CTL_RATE_CTRL_PROBE; 833 } else { 834 hdr->frame_control &= ~morefrags; 835 next_len = 0; 836 } 837 hdr->duration_id = ieee80211_duration(tx, 0, next_len); 838 hdr->seq_ctrl |= cpu_to_le16(fragnum & IEEE80211_SCTL_FRAG); 839 fragnum++; 840 } while ((skb = skb->next)); 841 842 return TX_CONTINUE; 843 } 844 845 static ieee80211_tx_result debug_noinline 846 ieee80211_tx_h_stats(struct ieee80211_tx_data *tx) 847 { 848 struct sk_buff *skb = tx->skb; 849 850 if (!tx->sta) 851 return TX_CONTINUE; 852 853 tx->sta->tx_packets++; 854 do { 855 tx->sta->tx_fragments++; 856 tx->sta->tx_bytes += skb->len; 857 } while ((skb = skb->next)); 858 859 return TX_CONTINUE; 860 } 861 862 static ieee80211_tx_result debug_noinline 863 ieee80211_tx_h_encrypt(struct ieee80211_tx_data *tx) 864 { 865 if (!tx->key) 866 return TX_CONTINUE; 867 868 switch (tx->key->conf.alg) { 869 case ALG_WEP: 870 return ieee80211_crypto_wep_encrypt(tx); 871 case ALG_TKIP: 872 return ieee80211_crypto_tkip_encrypt(tx); 873 case ALG_CCMP: 874 return ieee80211_crypto_ccmp_encrypt(tx); 875 case ALG_AES_CMAC: 876 return ieee80211_crypto_aes_cmac_encrypt(tx); 877 } 878 879 /* not reached */ 880 WARN_ON(1); 881 return TX_DROP; 882 } 883 884 static ieee80211_tx_result debug_noinline 885 ieee80211_tx_h_calculate_duration(struct ieee80211_tx_data *tx) 886 { 887 struct sk_buff *skb = tx->skb; 888 struct ieee80211_hdr *hdr; 889 int next_len; 890 bool group_addr; 891 892 do { 893 hdr = (void *) skb->data; 894 if (unlikely(ieee80211_is_pspoll(hdr->frame_control))) 895 break; /* must not overwrite AID */ 896 next_len = skb->next ? skb->next->len : 0; 897 group_addr = is_multicast_ether_addr(hdr->addr1); 898 899 hdr->duration_id = 900 ieee80211_duration(tx, group_addr, next_len); 901 } while ((skb = skb->next)); 902 903 return TX_CONTINUE; 904 } 905 906 /* actual transmit path */ 907 908 /* 909 * deal with packet injection down monitor interface 910 * with Radiotap Header -- only called for monitor mode interface 911 */ 912 static bool __ieee80211_parse_tx_radiotap(struct ieee80211_tx_data *tx, 913 struct sk_buff *skb) 914 { 915 /* 916 * this is the moment to interpret and discard the radiotap header that 917 * must be at the start of the packet injected in Monitor mode 918 * 919 * Need to take some care with endian-ness since radiotap 920 * args are little-endian 921 */ 922 923 struct ieee80211_radiotap_iterator iterator; 924 struct ieee80211_radiotap_header *rthdr = 925 (struct ieee80211_radiotap_header *) skb->data; 926 struct ieee80211_supported_band *sband; 927 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 928 int ret = ieee80211_radiotap_iterator_init(&iterator, rthdr, skb->len); 929 930 sband = tx->local->hw.wiphy->bands[tx->channel->band]; 931 932 info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT; 933 tx->flags &= ~IEEE80211_TX_FRAGMENTED; 934 935 /* 936 * for every radiotap entry that is present 937 * (ieee80211_radiotap_iterator_next returns -ENOENT when no more 938 * entries present, or -EINVAL on error) 939 */ 940 941 while (!ret) { 942 ret = ieee80211_radiotap_iterator_next(&iterator); 943 944 if (ret) 945 continue; 946 947 /* see if this argument is something we can use */ 948 switch (iterator.this_arg_index) { 949 /* 950 * You must take care when dereferencing iterator.this_arg 951 * for multibyte types... the pointer is not aligned. Use 952 * get_unaligned((type *)iterator.this_arg) to dereference 953 * iterator.this_arg for type "type" safely on all arches. 954 */ 955 case IEEE80211_RADIOTAP_FLAGS: 956 if (*iterator.this_arg & IEEE80211_RADIOTAP_F_FCS) { 957 /* 958 * this indicates that the skb we have been 959 * handed has the 32-bit FCS CRC at the end... 960 * we should react to that by snipping it off 961 * because it will be recomputed and added 962 * on transmission 963 */ 964 if (skb->len < (iterator.max_length + FCS_LEN)) 965 return false; 966 967 skb_trim(skb, skb->len - FCS_LEN); 968 } 969 if (*iterator.this_arg & IEEE80211_RADIOTAP_F_WEP) 970 info->flags &= ~IEEE80211_TX_INTFL_DONT_ENCRYPT; 971 if (*iterator.this_arg & IEEE80211_RADIOTAP_F_FRAG) 972 tx->flags |= IEEE80211_TX_FRAGMENTED; 973 break; 974 975 /* 976 * Please update the file 977 * Documentation/networking/mac80211-injection.txt 978 * when parsing new fields here. 979 */ 980 981 default: 982 break; 983 } 984 } 985 986 if (ret != -ENOENT) /* ie, if we didn't simply run out of fields */ 987 return false; 988 989 /* 990 * remove the radiotap header 991 * iterator->max_length was sanity-checked against 992 * skb->len by iterator init 993 */ 994 skb_pull(skb, iterator.max_length); 995 996 return true; 997 } 998 999 /* 1000 * initialises @tx 1001 */ 1002 static ieee80211_tx_result 1003 ieee80211_tx_prepare(struct ieee80211_sub_if_data *sdata, 1004 struct ieee80211_tx_data *tx, 1005 struct sk_buff *skb) 1006 { 1007 struct ieee80211_local *local = sdata->local; 1008 struct ieee80211_hdr *hdr; 1009 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 1010 int hdrlen, tid; 1011 u8 *qc, *state; 1012 bool queued = false; 1013 1014 memset(tx, 0, sizeof(*tx)); 1015 tx->skb = skb; 1016 tx->dev = sdata->dev; /* use original interface */ 1017 tx->local = local; 1018 tx->sdata = sdata; 1019 tx->channel = local->hw.conf.channel; 1020 /* 1021 * Set this flag (used below to indicate "automatic fragmentation"), 1022 * it will be cleared/left by radiotap as desired. 1023 */ 1024 tx->flags |= IEEE80211_TX_FRAGMENTED; 1025 1026 /* process and remove the injection radiotap header */ 1027 if (unlikely(info->flags & IEEE80211_TX_CTL_INJECTED)) { 1028 if (!__ieee80211_parse_tx_radiotap(tx, skb)) 1029 return TX_DROP; 1030 1031 /* 1032 * __ieee80211_parse_tx_radiotap has now removed 1033 * the radiotap header that was present and pre-filled 1034 * 'tx' with tx control information. 1035 */ 1036 } 1037 1038 /* 1039 * If this flag is set to true anywhere, and we get here, 1040 * we are doing the needed processing, so remove the flag 1041 * now. 1042 */ 1043 info->flags &= ~IEEE80211_TX_INTFL_NEED_TXPROCESSING; 1044 1045 hdr = (struct ieee80211_hdr *) skb->data; 1046 1047 tx->sta = sta_info_get(local, hdr->addr1); 1048 1049 if (tx->sta && ieee80211_is_data_qos(hdr->frame_control) && 1050 (local->hw.flags & IEEE80211_HW_AMPDU_AGGREGATION)) { 1051 unsigned long flags; 1052 struct tid_ampdu_tx *tid_tx; 1053 1054 qc = ieee80211_get_qos_ctl(hdr); 1055 tid = *qc & IEEE80211_QOS_CTL_TID_MASK; 1056 1057 spin_lock_irqsave(&tx->sta->lock, flags); 1058 /* 1059 * XXX: This spinlock could be fairly expensive, but see the 1060 * comment in agg-tx.c:ieee80211_agg_tx_operational(). 1061 * One way to solve this would be to do something RCU-like 1062 * for managing the tid_tx struct and using atomic bitops 1063 * for the actual state -- by introducing an actual 1064 * 'operational' bit that would be possible. It would 1065 * require changing ieee80211_agg_tx_operational() to 1066 * set that bit, and changing the way tid_tx is managed 1067 * everywhere, including races between that bit and 1068 * tid_tx going away (tid_tx being added can be easily 1069 * committed to memory before the 'operational' bit). 1070 */ 1071 tid_tx = tx->sta->ampdu_mlme.tid_tx[tid]; 1072 state = &tx->sta->ampdu_mlme.tid_state_tx[tid]; 1073 if (*state == HT_AGG_STATE_OPERATIONAL) { 1074 info->flags |= IEEE80211_TX_CTL_AMPDU; 1075 } else if (*state != HT_AGG_STATE_IDLE) { 1076 /* in progress */ 1077 queued = true; 1078 info->control.vif = &sdata->vif; 1079 info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING; 1080 __skb_queue_tail(&tid_tx->pending, skb); 1081 } 1082 spin_unlock_irqrestore(&tx->sta->lock, flags); 1083 1084 if (unlikely(queued)) 1085 return TX_QUEUED; 1086 } 1087 1088 if (is_multicast_ether_addr(hdr->addr1)) { 1089 tx->flags &= ~IEEE80211_TX_UNICAST; 1090 info->flags |= IEEE80211_TX_CTL_NO_ACK; 1091 } else { 1092 tx->flags |= IEEE80211_TX_UNICAST; 1093 if (unlikely(local->wifi_wme_noack_test)) 1094 info->flags |= IEEE80211_TX_CTL_NO_ACK; 1095 else 1096 info->flags &= ~IEEE80211_TX_CTL_NO_ACK; 1097 } 1098 1099 if (tx->flags & IEEE80211_TX_FRAGMENTED) { 1100 if ((tx->flags & IEEE80211_TX_UNICAST) && 1101 skb->len + FCS_LEN > local->hw.wiphy->frag_threshold && 1102 !(info->flags & IEEE80211_TX_CTL_AMPDU)) 1103 tx->flags |= IEEE80211_TX_FRAGMENTED; 1104 else 1105 tx->flags &= ~IEEE80211_TX_FRAGMENTED; 1106 } 1107 1108 if (!tx->sta) 1109 info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT; 1110 else if (test_and_clear_sta_flags(tx->sta, WLAN_STA_CLEAR_PS_FILT)) 1111 info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT; 1112 1113 hdrlen = ieee80211_hdrlen(hdr->frame_control); 1114 if (skb->len > hdrlen + sizeof(rfc1042_header) + 2) { 1115 u8 *pos = &skb->data[hdrlen + sizeof(rfc1042_header)]; 1116 tx->ethertype = (pos[0] << 8) | pos[1]; 1117 } 1118 info->flags |= IEEE80211_TX_CTL_FIRST_FRAGMENT; 1119 1120 return TX_CONTINUE; 1121 } 1122 1123 static int __ieee80211_tx(struct ieee80211_local *local, 1124 struct sk_buff **skbp, 1125 struct sta_info *sta, 1126 bool txpending) 1127 { 1128 struct sk_buff *skb = *skbp, *next; 1129 struct ieee80211_tx_info *info; 1130 struct ieee80211_sub_if_data *sdata; 1131 unsigned long flags; 1132 int ret, len; 1133 bool fragm = false; 1134 1135 while (skb) { 1136 int q = skb_get_queue_mapping(skb); 1137 1138 spin_lock_irqsave(&local->queue_stop_reason_lock, flags); 1139 ret = IEEE80211_TX_OK; 1140 if (local->queue_stop_reasons[q] || 1141 (!txpending && !skb_queue_empty(&local->pending[q]))) 1142 ret = IEEE80211_TX_PENDING; 1143 spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags); 1144 if (ret != IEEE80211_TX_OK) 1145 return ret; 1146 1147 info = IEEE80211_SKB_CB(skb); 1148 1149 if (fragm) 1150 info->flags &= ~(IEEE80211_TX_CTL_CLEAR_PS_FILT | 1151 IEEE80211_TX_CTL_FIRST_FRAGMENT); 1152 1153 next = skb->next; 1154 len = skb->len; 1155 1156 if (next) 1157 info->flags |= IEEE80211_TX_CTL_MORE_FRAMES; 1158 1159 sdata = vif_to_sdata(info->control.vif); 1160 1161 switch (sdata->vif.type) { 1162 case NL80211_IFTYPE_MONITOR: 1163 info->control.vif = NULL; 1164 break; 1165 case NL80211_IFTYPE_AP_VLAN: 1166 info->control.vif = &container_of(sdata->bss, 1167 struct ieee80211_sub_if_data, u.ap)->vif; 1168 break; 1169 default: 1170 /* keep */ 1171 break; 1172 } 1173 1174 ret = drv_tx(local, skb); 1175 if (WARN_ON(ret != NETDEV_TX_OK && skb->len != len)) { 1176 dev_kfree_skb(skb); 1177 ret = NETDEV_TX_OK; 1178 } 1179 if (ret != NETDEV_TX_OK) { 1180 info->control.vif = &sdata->vif; 1181 return IEEE80211_TX_AGAIN; 1182 } 1183 1184 *skbp = skb = next; 1185 ieee80211_led_tx(local, 1); 1186 fragm = true; 1187 } 1188 1189 return IEEE80211_TX_OK; 1190 } 1191 1192 /* 1193 * Invoke TX handlers, return 0 on success and non-zero if the 1194 * frame was dropped or queued. 1195 */ 1196 static int invoke_tx_handlers(struct ieee80211_tx_data *tx) 1197 { 1198 struct sk_buff *skb = tx->skb; 1199 ieee80211_tx_result res = TX_DROP; 1200 1201 #define CALL_TXH(txh) \ 1202 res = txh(tx); \ 1203 if (res != TX_CONTINUE) \ 1204 goto txh_done; 1205 1206 CALL_TXH(ieee80211_tx_h_check_assoc) 1207 CALL_TXH(ieee80211_tx_h_ps_buf) 1208 CALL_TXH(ieee80211_tx_h_select_key) 1209 CALL_TXH(ieee80211_tx_h_michael_mic_add) 1210 CALL_TXH(ieee80211_tx_h_rate_ctrl) 1211 CALL_TXH(ieee80211_tx_h_misc) 1212 CALL_TXH(ieee80211_tx_h_sequence) 1213 CALL_TXH(ieee80211_tx_h_fragment) 1214 /* handlers after fragment must be aware of tx info fragmentation! */ 1215 CALL_TXH(ieee80211_tx_h_stats) 1216 CALL_TXH(ieee80211_tx_h_encrypt) 1217 CALL_TXH(ieee80211_tx_h_calculate_duration) 1218 #undef CALL_TXH 1219 1220 txh_done: 1221 if (unlikely(res == TX_DROP)) { 1222 I802_DEBUG_INC(tx->local->tx_handlers_drop); 1223 while (skb) { 1224 struct sk_buff *next; 1225 1226 next = skb->next; 1227 dev_kfree_skb(skb); 1228 skb = next; 1229 } 1230 return -1; 1231 } else if (unlikely(res == TX_QUEUED)) { 1232 I802_DEBUG_INC(tx->local->tx_handlers_queued); 1233 return -1; 1234 } 1235 1236 return 0; 1237 } 1238 1239 static void ieee80211_tx(struct ieee80211_sub_if_data *sdata, 1240 struct sk_buff *skb, bool txpending) 1241 { 1242 struct ieee80211_local *local = sdata->local; 1243 struct ieee80211_tx_data tx; 1244 ieee80211_tx_result res_prepare; 1245 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 1246 struct sk_buff *next; 1247 unsigned long flags; 1248 int ret, retries; 1249 u16 queue; 1250 1251 queue = skb_get_queue_mapping(skb); 1252 1253 if (unlikely(skb->len < 10)) { 1254 dev_kfree_skb(skb); 1255 return; 1256 } 1257 1258 rcu_read_lock(); 1259 1260 /* initialises tx */ 1261 res_prepare = ieee80211_tx_prepare(sdata, &tx, skb); 1262 1263 if (unlikely(res_prepare == TX_DROP)) { 1264 dev_kfree_skb(skb); 1265 rcu_read_unlock(); 1266 return; 1267 } else if (unlikely(res_prepare == TX_QUEUED)) { 1268 rcu_read_unlock(); 1269 return; 1270 } 1271 1272 tx.channel = local->hw.conf.channel; 1273 info->band = tx.channel->band; 1274 1275 if (invoke_tx_handlers(&tx)) 1276 goto out; 1277 1278 retries = 0; 1279 retry: 1280 ret = __ieee80211_tx(local, &tx.skb, tx.sta, txpending); 1281 switch (ret) { 1282 case IEEE80211_TX_OK: 1283 break; 1284 case IEEE80211_TX_AGAIN: 1285 /* 1286 * Since there are no fragmented frames on A-MPDU 1287 * queues, there's no reason for a driver to reject 1288 * a frame there, warn and drop it. 1289 */ 1290 if (WARN_ON(info->flags & IEEE80211_TX_CTL_AMPDU)) 1291 goto drop; 1292 /* fall through */ 1293 case IEEE80211_TX_PENDING: 1294 skb = tx.skb; 1295 1296 spin_lock_irqsave(&local->queue_stop_reason_lock, flags); 1297 1298 if (local->queue_stop_reasons[queue] || 1299 !skb_queue_empty(&local->pending[queue])) { 1300 /* 1301 * if queue is stopped, queue up frames for later 1302 * transmission from the tasklet 1303 */ 1304 do { 1305 next = skb->next; 1306 skb->next = NULL; 1307 if (unlikely(txpending)) 1308 __skb_queue_head(&local->pending[queue], 1309 skb); 1310 else 1311 __skb_queue_tail(&local->pending[queue], 1312 skb); 1313 } while ((skb = next)); 1314 1315 spin_unlock_irqrestore(&local->queue_stop_reason_lock, 1316 flags); 1317 } else { 1318 /* 1319 * otherwise retry, but this is a race condition or 1320 * a driver bug (which we warn about if it persists) 1321 */ 1322 spin_unlock_irqrestore(&local->queue_stop_reason_lock, 1323 flags); 1324 1325 retries++; 1326 if (WARN(retries > 10, "tx refused but queue active\n")) 1327 goto drop; 1328 goto retry; 1329 } 1330 } 1331 out: 1332 rcu_read_unlock(); 1333 return; 1334 1335 drop: 1336 rcu_read_unlock(); 1337 1338 skb = tx.skb; 1339 while (skb) { 1340 next = skb->next; 1341 dev_kfree_skb(skb); 1342 skb = next; 1343 } 1344 } 1345 1346 /* device xmit handlers */ 1347 1348 static int ieee80211_skb_resize(struct ieee80211_local *local, 1349 struct sk_buff *skb, 1350 int head_need, bool may_encrypt) 1351 { 1352 int tail_need = 0; 1353 1354 /* 1355 * This could be optimised, devices that do full hardware 1356 * crypto (including TKIP MMIC) need no tailroom... But we 1357 * have no drivers for such devices currently. 1358 */ 1359 if (may_encrypt) { 1360 tail_need = IEEE80211_ENCRYPT_TAILROOM; 1361 tail_need -= skb_tailroom(skb); 1362 tail_need = max_t(int, tail_need, 0); 1363 } 1364 1365 if (head_need || tail_need) { 1366 /* Sorry. Can't account for this any more */ 1367 skb_orphan(skb); 1368 } 1369 1370 if (skb_header_cloned(skb)) 1371 I802_DEBUG_INC(local->tx_expand_skb_head_cloned); 1372 else 1373 I802_DEBUG_INC(local->tx_expand_skb_head); 1374 1375 if (pskb_expand_head(skb, head_need, tail_need, GFP_ATOMIC)) { 1376 printk(KERN_DEBUG "%s: failed to reallocate TX buffer\n", 1377 wiphy_name(local->hw.wiphy)); 1378 return -ENOMEM; 1379 } 1380 1381 /* update truesize too */ 1382 skb->truesize += head_need + tail_need; 1383 1384 return 0; 1385 } 1386 1387 static void ieee80211_xmit(struct ieee80211_sub_if_data *sdata, 1388 struct sk_buff *skb) 1389 { 1390 struct ieee80211_local *local = sdata->local; 1391 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 1392 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 1393 struct ieee80211_sub_if_data *tmp_sdata; 1394 int headroom; 1395 bool may_encrypt; 1396 1397 dev_hold(sdata->dev); 1398 1399 if ((local->hw.flags & IEEE80211_HW_PS_NULLFUNC_STACK) && 1400 local->hw.conf.dynamic_ps_timeout > 0 && 1401 !(local->scanning) && local->ps_sdata) { 1402 if (local->hw.conf.flags & IEEE80211_CONF_PS) { 1403 ieee80211_stop_queues_by_reason(&local->hw, 1404 IEEE80211_QUEUE_STOP_REASON_PS); 1405 ieee80211_queue_work(&local->hw, 1406 &local->dynamic_ps_disable_work); 1407 } 1408 1409 mod_timer(&local->dynamic_ps_timer, jiffies + 1410 msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout)); 1411 } 1412 1413 info->flags |= IEEE80211_TX_CTL_REQ_TX_STATUS; 1414 1415 if (unlikely(sdata->vif.type == NL80211_IFTYPE_MONITOR)) { 1416 int hdrlen; 1417 u16 len_rthdr; 1418 1419 info->flags |= IEEE80211_TX_CTL_INJECTED; 1420 1421 len_rthdr = ieee80211_get_radiotap_len(skb->data); 1422 hdr = (struct ieee80211_hdr *)(skb->data + len_rthdr); 1423 hdrlen = ieee80211_hdrlen(hdr->frame_control); 1424 1425 /* check the header is complete in the frame */ 1426 if (likely(skb->len >= len_rthdr + hdrlen)) { 1427 /* 1428 * We process outgoing injected frames that have a 1429 * local address we handle as though they are our 1430 * own frames. 1431 * This code here isn't entirely correct, the local 1432 * MAC address is not necessarily enough to find 1433 * the interface to use; for that proper VLAN/WDS 1434 * support we will need a different mechanism. 1435 */ 1436 1437 rcu_read_lock(); 1438 list_for_each_entry_rcu(tmp_sdata, &local->interfaces, 1439 list) { 1440 if (!netif_running(tmp_sdata->dev)) 1441 continue; 1442 if (tmp_sdata->vif.type != NL80211_IFTYPE_AP) 1443 continue; 1444 if (compare_ether_addr(tmp_sdata->dev->dev_addr, 1445 hdr->addr2)) { 1446 dev_hold(tmp_sdata->dev); 1447 dev_put(sdata->dev); 1448 sdata = tmp_sdata; 1449 break; 1450 } 1451 } 1452 rcu_read_unlock(); 1453 } 1454 } 1455 1456 may_encrypt = !(info->flags & IEEE80211_TX_INTFL_DONT_ENCRYPT); 1457 1458 headroom = local->tx_headroom; 1459 if (may_encrypt) 1460 headroom += IEEE80211_ENCRYPT_HEADROOM; 1461 headroom -= skb_headroom(skb); 1462 headroom = max_t(int, 0, headroom); 1463 1464 if (ieee80211_skb_resize(local, skb, headroom, may_encrypt)) { 1465 dev_kfree_skb(skb); 1466 dev_put(sdata->dev); 1467 return; 1468 } 1469 1470 info->control.vif = &sdata->vif; 1471 1472 if (ieee80211_vif_is_mesh(&sdata->vif) && 1473 ieee80211_is_data(hdr->frame_control) && 1474 !is_multicast_ether_addr(hdr->addr1)) 1475 if (mesh_nexthop_lookup(skb, sdata)) { 1476 /* skb queued: don't free */ 1477 dev_put(sdata->dev); 1478 return; 1479 } 1480 1481 ieee80211_select_queue(local, skb); 1482 ieee80211_tx(sdata, skb, false); 1483 dev_put(sdata->dev); 1484 } 1485 1486 netdev_tx_t ieee80211_monitor_start_xmit(struct sk_buff *skb, 1487 struct net_device *dev) 1488 { 1489 struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr); 1490 struct ieee80211_channel *chan = local->hw.conf.channel; 1491 struct ieee80211_radiotap_header *prthdr = 1492 (struct ieee80211_radiotap_header *)skb->data; 1493 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 1494 u16 len_rthdr; 1495 1496 /* 1497 * Frame injection is not allowed if beaconing is not allowed 1498 * or if we need radar detection. Beaconing is usually not allowed when 1499 * the mode or operation (Adhoc, AP, Mesh) does not support DFS. 1500 * Passive scan is also used in world regulatory domains where 1501 * your country is not known and as such it should be treated as 1502 * NO TX unless the channel is explicitly allowed in which case 1503 * your current regulatory domain would not have the passive scan 1504 * flag. 1505 * 1506 * Since AP mode uses monitor interfaces to inject/TX management 1507 * frames we can make AP mode the exception to this rule once it 1508 * supports radar detection as its implementation can deal with 1509 * radar detection by itself. We can do that later by adding a 1510 * monitor flag interfaces used for AP support. 1511 */ 1512 if ((chan->flags & (IEEE80211_CHAN_NO_IBSS | IEEE80211_CHAN_RADAR | 1513 IEEE80211_CHAN_PASSIVE_SCAN))) 1514 goto fail; 1515 1516 /* check for not even having the fixed radiotap header part */ 1517 if (unlikely(skb->len < sizeof(struct ieee80211_radiotap_header))) 1518 goto fail; /* too short to be possibly valid */ 1519 1520 /* is it a header version we can trust to find length from? */ 1521 if (unlikely(prthdr->it_version)) 1522 goto fail; /* only version 0 is supported */ 1523 1524 /* then there must be a radiotap header with a length we can use */ 1525 len_rthdr = ieee80211_get_radiotap_len(skb->data); 1526 1527 /* does the skb contain enough to deliver on the alleged length? */ 1528 if (unlikely(skb->len < len_rthdr)) 1529 goto fail; /* skb too short for claimed rt header extent */ 1530 1531 /* 1532 * fix up the pointers accounting for the radiotap 1533 * header still being in there. We are being given 1534 * a precooked IEEE80211 header so no need for 1535 * normal processing 1536 */ 1537 skb_set_mac_header(skb, len_rthdr); 1538 /* 1539 * these are just fixed to the end of the rt area since we 1540 * don't have any better information and at this point, nobody cares 1541 */ 1542 skb_set_network_header(skb, len_rthdr); 1543 skb_set_transport_header(skb, len_rthdr); 1544 1545 memset(info, 0, sizeof(*info)); 1546 1547 /* pass the radiotap header up to xmit */ 1548 ieee80211_xmit(IEEE80211_DEV_TO_SUB_IF(dev), skb); 1549 return NETDEV_TX_OK; 1550 1551 fail: 1552 dev_kfree_skb(skb); 1553 return NETDEV_TX_OK; /* meaning, we dealt with the skb */ 1554 } 1555 1556 /** 1557 * ieee80211_subif_start_xmit - netif start_xmit function for Ethernet-type 1558 * subinterfaces (wlan#, WDS, and VLAN interfaces) 1559 * @skb: packet to be sent 1560 * @dev: incoming interface 1561 * 1562 * Returns: 0 on success (and frees skb in this case) or 1 on failure (skb will 1563 * not be freed, and caller is responsible for either retrying later or freeing 1564 * skb). 1565 * 1566 * This function takes in an Ethernet header and encapsulates it with suitable 1567 * IEEE 802.11 header based on which interface the packet is coming in. The 1568 * encapsulated packet will then be passed to master interface, wlan#.11, for 1569 * transmission (through low-level driver). 1570 */ 1571 netdev_tx_t ieee80211_subif_start_xmit(struct sk_buff *skb, 1572 struct net_device *dev) 1573 { 1574 struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev); 1575 struct ieee80211_local *local = sdata->local; 1576 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 1577 int ret = NETDEV_TX_BUSY, head_need; 1578 u16 ethertype, hdrlen, meshhdrlen = 0; 1579 __le16 fc; 1580 struct ieee80211_hdr hdr; 1581 struct ieee80211s_hdr mesh_hdr; 1582 const u8 *encaps_data; 1583 int encaps_len, skip_header_bytes; 1584 int nh_pos, h_pos; 1585 struct sta_info *sta; 1586 u32 sta_flags = 0; 1587 1588 if (unlikely(skb->len < ETH_HLEN)) { 1589 ret = NETDEV_TX_OK; 1590 goto fail; 1591 } 1592 1593 nh_pos = skb_network_header(skb) - skb->data; 1594 h_pos = skb_transport_header(skb) - skb->data; 1595 1596 /* convert Ethernet header to proper 802.11 header (based on 1597 * operation mode) */ 1598 ethertype = (skb->data[12] << 8) | skb->data[13]; 1599 fc = cpu_to_le16(IEEE80211_FTYPE_DATA | IEEE80211_STYPE_DATA); 1600 1601 switch (sdata->vif.type) { 1602 case NL80211_IFTYPE_AP: 1603 case NL80211_IFTYPE_AP_VLAN: 1604 fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS); 1605 /* DA BSSID SA */ 1606 memcpy(hdr.addr1, skb->data, ETH_ALEN); 1607 memcpy(hdr.addr2, dev->dev_addr, ETH_ALEN); 1608 memcpy(hdr.addr3, skb->data + ETH_ALEN, ETH_ALEN); 1609 hdrlen = 24; 1610 break; 1611 case NL80211_IFTYPE_WDS: 1612 fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS); 1613 /* RA TA DA SA */ 1614 memcpy(hdr.addr1, sdata->u.wds.remote_addr, ETH_ALEN); 1615 memcpy(hdr.addr2, dev->dev_addr, ETH_ALEN); 1616 memcpy(hdr.addr3, skb->data, ETH_ALEN); 1617 memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN); 1618 hdrlen = 30; 1619 break; 1620 #ifdef CONFIG_MAC80211_MESH 1621 case NL80211_IFTYPE_MESH_POINT: 1622 if (!sdata->u.mesh.mshcfg.dot11MeshTTL) { 1623 /* Do not send frames with mesh_ttl == 0 */ 1624 sdata->u.mesh.mshstats.dropped_frames_ttl++; 1625 ret = NETDEV_TX_OK; 1626 goto fail; 1627 } 1628 1629 if (compare_ether_addr(dev->dev_addr, 1630 skb->data + ETH_ALEN) == 0) { 1631 hdrlen = ieee80211_fill_mesh_addresses(&hdr, &fc, 1632 skb->data, skb->data + ETH_ALEN); 1633 meshhdrlen = ieee80211_new_mesh_header(&mesh_hdr, 1634 sdata, NULL, NULL, NULL); 1635 } else { 1636 /* packet from other interface */ 1637 struct mesh_path *mppath; 1638 int is_mesh_mcast = 1; 1639 char *mesh_da; 1640 1641 rcu_read_lock(); 1642 if (is_multicast_ether_addr(skb->data)) 1643 /* DA TA mSA AE:SA */ 1644 mesh_da = skb->data; 1645 else { 1646 mppath = mpp_path_lookup(skb->data, sdata); 1647 if (mppath) { 1648 /* RA TA mDA mSA AE:DA SA */ 1649 mesh_da = mppath->mpp; 1650 is_mesh_mcast = 0; 1651 } else 1652 /* DA TA mSA AE:SA */ 1653 mesh_da = dev->broadcast; 1654 } 1655 hdrlen = ieee80211_fill_mesh_addresses(&hdr, &fc, 1656 mesh_da, dev->dev_addr); 1657 rcu_read_unlock(); 1658 if (is_mesh_mcast) 1659 meshhdrlen = 1660 ieee80211_new_mesh_header(&mesh_hdr, 1661 sdata, 1662 skb->data + ETH_ALEN, 1663 NULL, 1664 NULL); 1665 else 1666 meshhdrlen = 1667 ieee80211_new_mesh_header(&mesh_hdr, 1668 sdata, 1669 NULL, 1670 skb->data, 1671 skb->data + ETH_ALEN); 1672 1673 } 1674 break; 1675 #endif 1676 case NL80211_IFTYPE_STATION: 1677 fc |= cpu_to_le16(IEEE80211_FCTL_TODS); 1678 /* BSSID SA DA */ 1679 memcpy(hdr.addr1, sdata->u.mgd.bssid, ETH_ALEN); 1680 memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN); 1681 memcpy(hdr.addr3, skb->data, ETH_ALEN); 1682 hdrlen = 24; 1683 break; 1684 case NL80211_IFTYPE_ADHOC: 1685 /* DA SA BSSID */ 1686 memcpy(hdr.addr1, skb->data, ETH_ALEN); 1687 memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN); 1688 memcpy(hdr.addr3, sdata->u.ibss.bssid, ETH_ALEN); 1689 hdrlen = 24; 1690 break; 1691 default: 1692 ret = NETDEV_TX_OK; 1693 goto fail; 1694 } 1695 1696 /* 1697 * There's no need to try to look up the destination 1698 * if it is a multicast address (which can only happen 1699 * in AP mode) 1700 */ 1701 if (!is_multicast_ether_addr(hdr.addr1)) { 1702 rcu_read_lock(); 1703 sta = sta_info_get(local, hdr.addr1); 1704 if (sta) 1705 sta_flags = get_sta_flags(sta); 1706 rcu_read_unlock(); 1707 } 1708 1709 /* receiver and we are QoS enabled, use a QoS type frame */ 1710 if ((sta_flags & WLAN_STA_WME) && local->hw.queues >= 4) { 1711 fc |= cpu_to_le16(IEEE80211_STYPE_QOS_DATA); 1712 hdrlen += 2; 1713 } 1714 1715 /* 1716 * Drop unicast frames to unauthorised stations unless they are 1717 * EAPOL frames from the local station. 1718 */ 1719 if (!ieee80211_vif_is_mesh(&sdata->vif) && 1720 unlikely(!is_multicast_ether_addr(hdr.addr1) && 1721 !(sta_flags & WLAN_STA_AUTHORIZED) && 1722 !(ethertype == ETH_P_PAE && 1723 compare_ether_addr(dev->dev_addr, 1724 skb->data + ETH_ALEN) == 0))) { 1725 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG 1726 if (net_ratelimit()) 1727 printk(KERN_DEBUG "%s: dropped frame to %pM" 1728 " (unauthorized port)\n", dev->name, 1729 hdr.addr1); 1730 #endif 1731 1732 I802_DEBUG_INC(local->tx_handlers_drop_unauth_port); 1733 1734 ret = NETDEV_TX_OK; 1735 goto fail; 1736 } 1737 1738 hdr.frame_control = fc; 1739 hdr.duration_id = 0; 1740 hdr.seq_ctrl = 0; 1741 1742 skip_header_bytes = ETH_HLEN; 1743 if (ethertype == ETH_P_AARP || ethertype == ETH_P_IPX) { 1744 encaps_data = bridge_tunnel_header; 1745 encaps_len = sizeof(bridge_tunnel_header); 1746 skip_header_bytes -= 2; 1747 } else if (ethertype >= 0x600) { 1748 encaps_data = rfc1042_header; 1749 encaps_len = sizeof(rfc1042_header); 1750 skip_header_bytes -= 2; 1751 } else { 1752 encaps_data = NULL; 1753 encaps_len = 0; 1754 } 1755 1756 skb_pull(skb, skip_header_bytes); 1757 nh_pos -= skip_header_bytes; 1758 h_pos -= skip_header_bytes; 1759 1760 head_need = hdrlen + encaps_len + meshhdrlen - skb_headroom(skb); 1761 1762 /* 1763 * So we need to modify the skb header and hence need a copy of 1764 * that. The head_need variable above doesn't, so far, include 1765 * the needed header space that we don't need right away. If we 1766 * can, then we don't reallocate right now but only after the 1767 * frame arrives at the master device (if it does...) 1768 * 1769 * If we cannot, however, then we will reallocate to include all 1770 * the ever needed space. Also, if we need to reallocate it anyway, 1771 * make it big enough for everything we may ever need. 1772 */ 1773 1774 if (head_need > 0 || skb_cloned(skb)) { 1775 head_need += IEEE80211_ENCRYPT_HEADROOM; 1776 head_need += local->tx_headroom; 1777 head_need = max_t(int, 0, head_need); 1778 if (ieee80211_skb_resize(local, skb, head_need, true)) 1779 goto fail; 1780 } 1781 1782 if (encaps_data) { 1783 memcpy(skb_push(skb, encaps_len), encaps_data, encaps_len); 1784 nh_pos += encaps_len; 1785 h_pos += encaps_len; 1786 } 1787 1788 if (meshhdrlen > 0) { 1789 memcpy(skb_push(skb, meshhdrlen), &mesh_hdr, meshhdrlen); 1790 nh_pos += meshhdrlen; 1791 h_pos += meshhdrlen; 1792 } 1793 1794 if (ieee80211_is_data_qos(fc)) { 1795 __le16 *qos_control; 1796 1797 qos_control = (__le16*) skb_push(skb, 2); 1798 memcpy(skb_push(skb, hdrlen - 2), &hdr, hdrlen - 2); 1799 /* 1800 * Maybe we could actually set some fields here, for now just 1801 * initialise to zero to indicate no special operation. 1802 */ 1803 *qos_control = 0; 1804 } else 1805 memcpy(skb_push(skb, hdrlen), &hdr, hdrlen); 1806 1807 nh_pos += hdrlen; 1808 h_pos += hdrlen; 1809 1810 dev->stats.tx_packets++; 1811 dev->stats.tx_bytes += skb->len; 1812 1813 /* Update skb pointers to various headers since this modified frame 1814 * is going to go through Linux networking code that may potentially 1815 * need things like pointer to IP header. */ 1816 skb_set_mac_header(skb, 0); 1817 skb_set_network_header(skb, nh_pos); 1818 skb_set_transport_header(skb, h_pos); 1819 1820 memset(info, 0, sizeof(*info)); 1821 1822 dev->trans_start = jiffies; 1823 ieee80211_xmit(sdata, skb); 1824 1825 return NETDEV_TX_OK; 1826 1827 fail: 1828 if (ret == NETDEV_TX_OK) 1829 dev_kfree_skb(skb); 1830 1831 return ret; 1832 } 1833 1834 1835 /* 1836 * ieee80211_clear_tx_pending may not be called in a context where 1837 * it is possible that it packets could come in again. 1838 */ 1839 void ieee80211_clear_tx_pending(struct ieee80211_local *local) 1840 { 1841 int i; 1842 1843 for (i = 0; i < local->hw.queues; i++) 1844 skb_queue_purge(&local->pending[i]); 1845 } 1846 1847 static bool ieee80211_tx_pending_skb(struct ieee80211_local *local, 1848 struct sk_buff *skb) 1849 { 1850 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 1851 struct ieee80211_sub_if_data *sdata; 1852 struct sta_info *sta; 1853 struct ieee80211_hdr *hdr; 1854 int ret; 1855 bool result = true; 1856 1857 sdata = vif_to_sdata(info->control.vif); 1858 1859 if (info->flags & IEEE80211_TX_INTFL_NEED_TXPROCESSING) { 1860 ieee80211_tx(sdata, skb, true); 1861 } else { 1862 hdr = (struct ieee80211_hdr *)skb->data; 1863 sta = sta_info_get(local, hdr->addr1); 1864 1865 ret = __ieee80211_tx(local, &skb, sta, true); 1866 if (ret != IEEE80211_TX_OK) 1867 result = false; 1868 } 1869 1870 return result; 1871 } 1872 1873 /* 1874 * Transmit all pending packets. Called from tasklet. 1875 */ 1876 void ieee80211_tx_pending(unsigned long data) 1877 { 1878 struct ieee80211_local *local = (struct ieee80211_local *)data; 1879 unsigned long flags; 1880 int i; 1881 bool txok; 1882 1883 rcu_read_lock(); 1884 1885 spin_lock_irqsave(&local->queue_stop_reason_lock, flags); 1886 for (i = 0; i < local->hw.queues; i++) { 1887 /* 1888 * If queue is stopped by something other than due to pending 1889 * frames, or we have no pending frames, proceed to next queue. 1890 */ 1891 if (local->queue_stop_reasons[i] || 1892 skb_queue_empty(&local->pending[i])) 1893 continue; 1894 1895 while (!skb_queue_empty(&local->pending[i])) { 1896 struct sk_buff *skb = __skb_dequeue(&local->pending[i]); 1897 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 1898 struct ieee80211_sub_if_data *sdata; 1899 1900 if (WARN_ON(!info->control.vif)) { 1901 kfree_skb(skb); 1902 continue; 1903 } 1904 1905 sdata = vif_to_sdata(info->control.vif); 1906 dev_hold(sdata->dev); 1907 spin_unlock_irqrestore(&local->queue_stop_reason_lock, 1908 flags); 1909 1910 txok = ieee80211_tx_pending_skb(local, skb); 1911 dev_put(sdata->dev); 1912 if (!txok) 1913 __skb_queue_head(&local->pending[i], skb); 1914 spin_lock_irqsave(&local->queue_stop_reason_lock, 1915 flags); 1916 if (!txok) 1917 break; 1918 } 1919 } 1920 spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags); 1921 1922 rcu_read_unlock(); 1923 } 1924 1925 /* functions for drivers to get certain frames */ 1926 1927 static void ieee80211_beacon_add_tim(struct ieee80211_if_ap *bss, 1928 struct sk_buff *skb, 1929 struct beacon_data *beacon) 1930 { 1931 u8 *pos, *tim; 1932 int aid0 = 0; 1933 int i, have_bits = 0, n1, n2; 1934 1935 /* Generate bitmap for TIM only if there are any STAs in power save 1936 * mode. */ 1937 if (atomic_read(&bss->num_sta_ps) > 0) 1938 /* in the hope that this is faster than 1939 * checking byte-for-byte */ 1940 have_bits = !bitmap_empty((unsigned long*)bss->tim, 1941 IEEE80211_MAX_AID+1); 1942 1943 if (bss->dtim_count == 0) 1944 bss->dtim_count = beacon->dtim_period - 1; 1945 else 1946 bss->dtim_count--; 1947 1948 tim = pos = (u8 *) skb_put(skb, 6); 1949 *pos++ = WLAN_EID_TIM; 1950 *pos++ = 4; 1951 *pos++ = bss->dtim_count; 1952 *pos++ = beacon->dtim_period; 1953 1954 if (bss->dtim_count == 0 && !skb_queue_empty(&bss->ps_bc_buf)) 1955 aid0 = 1; 1956 1957 if (have_bits) { 1958 /* Find largest even number N1 so that bits numbered 1 through 1959 * (N1 x 8) - 1 in the bitmap are 0 and number N2 so that bits 1960 * (N2 + 1) x 8 through 2007 are 0. */ 1961 n1 = 0; 1962 for (i = 0; i < IEEE80211_MAX_TIM_LEN; i++) { 1963 if (bss->tim[i]) { 1964 n1 = i & 0xfe; 1965 break; 1966 } 1967 } 1968 n2 = n1; 1969 for (i = IEEE80211_MAX_TIM_LEN - 1; i >= n1; i--) { 1970 if (bss->tim[i]) { 1971 n2 = i; 1972 break; 1973 } 1974 } 1975 1976 /* Bitmap control */ 1977 *pos++ = n1 | aid0; 1978 /* Part Virt Bitmap */ 1979 memcpy(pos, bss->tim + n1, n2 - n1 + 1); 1980 1981 tim[1] = n2 - n1 + 4; 1982 skb_put(skb, n2 - n1); 1983 } else { 1984 *pos++ = aid0; /* Bitmap control */ 1985 *pos++ = 0; /* Part Virt Bitmap */ 1986 } 1987 } 1988 1989 struct sk_buff *ieee80211_beacon_get(struct ieee80211_hw *hw, 1990 struct ieee80211_vif *vif) 1991 { 1992 struct ieee80211_local *local = hw_to_local(hw); 1993 struct sk_buff *skb = NULL; 1994 struct ieee80211_tx_info *info; 1995 struct ieee80211_sub_if_data *sdata = NULL; 1996 struct ieee80211_if_ap *ap = NULL; 1997 struct beacon_data *beacon; 1998 struct ieee80211_supported_band *sband; 1999 enum ieee80211_band band = local->hw.conf.channel->band; 2000 2001 sband = local->hw.wiphy->bands[band]; 2002 2003 rcu_read_lock(); 2004 2005 sdata = vif_to_sdata(vif); 2006 2007 if (sdata->vif.type == NL80211_IFTYPE_AP) { 2008 ap = &sdata->u.ap; 2009 beacon = rcu_dereference(ap->beacon); 2010 if (ap && beacon) { 2011 /* 2012 * headroom, head length, 2013 * tail length and maximum TIM length 2014 */ 2015 skb = dev_alloc_skb(local->tx_headroom + 2016 beacon->head_len + 2017 beacon->tail_len + 256); 2018 if (!skb) 2019 goto out; 2020 2021 skb_reserve(skb, local->tx_headroom); 2022 memcpy(skb_put(skb, beacon->head_len), beacon->head, 2023 beacon->head_len); 2024 2025 /* 2026 * Not very nice, but we want to allow the driver to call 2027 * ieee80211_beacon_get() as a response to the set_tim() 2028 * callback. That, however, is already invoked under the 2029 * sta_lock to guarantee consistent and race-free update 2030 * of the tim bitmap in mac80211 and the driver. 2031 */ 2032 if (local->tim_in_locked_section) { 2033 ieee80211_beacon_add_tim(ap, skb, beacon); 2034 } else { 2035 unsigned long flags; 2036 2037 spin_lock_irqsave(&local->sta_lock, flags); 2038 ieee80211_beacon_add_tim(ap, skb, beacon); 2039 spin_unlock_irqrestore(&local->sta_lock, flags); 2040 } 2041 2042 if (beacon->tail) 2043 memcpy(skb_put(skb, beacon->tail_len), 2044 beacon->tail, beacon->tail_len); 2045 } else 2046 goto out; 2047 } else if (sdata->vif.type == NL80211_IFTYPE_ADHOC) { 2048 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 2049 struct ieee80211_hdr *hdr; 2050 struct sk_buff *presp = rcu_dereference(ifibss->presp); 2051 2052 if (!presp) 2053 goto out; 2054 2055 skb = skb_copy(presp, GFP_ATOMIC); 2056 if (!skb) 2057 goto out; 2058 2059 hdr = (struct ieee80211_hdr *) skb->data; 2060 hdr->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 2061 IEEE80211_STYPE_BEACON); 2062 } else if (ieee80211_vif_is_mesh(&sdata->vif)) { 2063 struct ieee80211_mgmt *mgmt; 2064 u8 *pos; 2065 2066 /* headroom, head length, tail length and maximum TIM length */ 2067 skb = dev_alloc_skb(local->tx_headroom + 400); 2068 if (!skb) 2069 goto out; 2070 2071 skb_reserve(skb, local->hw.extra_tx_headroom); 2072 mgmt = (struct ieee80211_mgmt *) 2073 skb_put(skb, 24 + sizeof(mgmt->u.beacon)); 2074 memset(mgmt, 0, 24 + sizeof(mgmt->u.beacon)); 2075 mgmt->frame_control = 2076 cpu_to_le16(IEEE80211_FTYPE_MGMT | IEEE80211_STYPE_BEACON); 2077 memset(mgmt->da, 0xff, ETH_ALEN); 2078 memcpy(mgmt->sa, sdata->dev->dev_addr, ETH_ALEN); 2079 /* BSSID is left zeroed, wildcard value */ 2080 mgmt->u.beacon.beacon_int = 2081 cpu_to_le16(sdata->vif.bss_conf.beacon_int); 2082 mgmt->u.beacon.capab_info = 0x0; /* 0x0 for MPs */ 2083 2084 pos = skb_put(skb, 2); 2085 *pos++ = WLAN_EID_SSID; 2086 *pos++ = 0x0; 2087 2088 mesh_mgmt_ies_add(skb, sdata); 2089 } else { 2090 WARN_ON(1); 2091 goto out; 2092 } 2093 2094 info = IEEE80211_SKB_CB(skb); 2095 2096 info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT; 2097 info->band = band; 2098 /* 2099 * XXX: For now, always use the lowest rate 2100 */ 2101 info->control.rates[0].idx = 0; 2102 info->control.rates[0].count = 1; 2103 info->control.rates[1].idx = -1; 2104 info->control.rates[2].idx = -1; 2105 info->control.rates[3].idx = -1; 2106 info->control.rates[4].idx = -1; 2107 BUILD_BUG_ON(IEEE80211_TX_MAX_RATES != 5); 2108 2109 info->control.vif = vif; 2110 2111 info->flags |= IEEE80211_TX_CTL_NO_ACK; 2112 info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT; 2113 info->flags |= IEEE80211_TX_CTL_ASSIGN_SEQ; 2114 out: 2115 rcu_read_unlock(); 2116 return skb; 2117 } 2118 EXPORT_SYMBOL(ieee80211_beacon_get); 2119 2120 void ieee80211_rts_get(struct ieee80211_hw *hw, struct ieee80211_vif *vif, 2121 const void *frame, size_t frame_len, 2122 const struct ieee80211_tx_info *frame_txctl, 2123 struct ieee80211_rts *rts) 2124 { 2125 const struct ieee80211_hdr *hdr = frame; 2126 2127 rts->frame_control = 2128 cpu_to_le16(IEEE80211_FTYPE_CTL | IEEE80211_STYPE_RTS); 2129 rts->duration = ieee80211_rts_duration(hw, vif, frame_len, 2130 frame_txctl); 2131 memcpy(rts->ra, hdr->addr1, sizeof(rts->ra)); 2132 memcpy(rts->ta, hdr->addr2, sizeof(rts->ta)); 2133 } 2134 EXPORT_SYMBOL(ieee80211_rts_get); 2135 2136 void ieee80211_ctstoself_get(struct ieee80211_hw *hw, struct ieee80211_vif *vif, 2137 const void *frame, size_t frame_len, 2138 const struct ieee80211_tx_info *frame_txctl, 2139 struct ieee80211_cts *cts) 2140 { 2141 const struct ieee80211_hdr *hdr = frame; 2142 2143 cts->frame_control = 2144 cpu_to_le16(IEEE80211_FTYPE_CTL | IEEE80211_STYPE_CTS); 2145 cts->duration = ieee80211_ctstoself_duration(hw, vif, 2146 frame_len, frame_txctl); 2147 memcpy(cts->ra, hdr->addr1, sizeof(cts->ra)); 2148 } 2149 EXPORT_SYMBOL(ieee80211_ctstoself_get); 2150 2151 struct sk_buff * 2152 ieee80211_get_buffered_bc(struct ieee80211_hw *hw, 2153 struct ieee80211_vif *vif) 2154 { 2155 struct ieee80211_local *local = hw_to_local(hw); 2156 struct sk_buff *skb = NULL; 2157 struct sta_info *sta; 2158 struct ieee80211_tx_data tx; 2159 struct ieee80211_sub_if_data *sdata; 2160 struct ieee80211_if_ap *bss = NULL; 2161 struct beacon_data *beacon; 2162 struct ieee80211_tx_info *info; 2163 2164 sdata = vif_to_sdata(vif); 2165 bss = &sdata->u.ap; 2166 2167 rcu_read_lock(); 2168 beacon = rcu_dereference(bss->beacon); 2169 2170 if (sdata->vif.type != NL80211_IFTYPE_AP || !beacon || !beacon->head) 2171 goto out; 2172 2173 if (bss->dtim_count != 0) 2174 goto out; /* send buffered bc/mc only after DTIM beacon */ 2175 2176 while (1) { 2177 skb = skb_dequeue(&bss->ps_bc_buf); 2178 if (!skb) 2179 goto out; 2180 local->total_ps_buffered--; 2181 2182 if (!skb_queue_empty(&bss->ps_bc_buf) && skb->len >= 2) { 2183 struct ieee80211_hdr *hdr = 2184 (struct ieee80211_hdr *) skb->data; 2185 /* more buffered multicast/broadcast frames ==> set 2186 * MoreData flag in IEEE 802.11 header to inform PS 2187 * STAs */ 2188 hdr->frame_control |= 2189 cpu_to_le16(IEEE80211_FCTL_MOREDATA); 2190 } 2191 2192 if (!ieee80211_tx_prepare(sdata, &tx, skb)) 2193 break; 2194 dev_kfree_skb_any(skb); 2195 } 2196 2197 info = IEEE80211_SKB_CB(skb); 2198 2199 sta = tx.sta; 2200 tx.flags |= IEEE80211_TX_PS_BUFFERED; 2201 tx.channel = local->hw.conf.channel; 2202 info->band = tx.channel->band; 2203 2204 if (invoke_tx_handlers(&tx)) 2205 skb = NULL; 2206 out: 2207 rcu_read_unlock(); 2208 2209 return skb; 2210 } 2211 EXPORT_SYMBOL(ieee80211_get_buffered_bc); 2212 2213 void ieee80211_tx_skb(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb, 2214 int encrypt) 2215 { 2216 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 2217 skb_set_mac_header(skb, 0); 2218 skb_set_network_header(skb, 0); 2219 skb_set_transport_header(skb, 0); 2220 2221 if (!encrypt) 2222 info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT; 2223 2224 /* 2225 * The other path calling ieee80211_xmit is from the tasklet, 2226 * and while we can handle concurrent transmissions locking 2227 * requirements are that we do not come into tx with bhs on. 2228 */ 2229 local_bh_disable(); 2230 ieee80211_xmit(sdata, skb); 2231 local_bh_enable(); 2232 } 2233