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 || ieee80211_is_auth(hdr->frame_control) 372 || ieee80211_is_assoc_resp(hdr->frame_control) 373 || ieee80211_is_reassoc_resp(hdr->frame_control))) 374 return TX_CONTINUE; 375 376 staflags = get_sta_flags(sta); 377 378 if (unlikely((staflags & WLAN_STA_PS) && 379 !(info->flags & IEEE80211_TX_CTL_PSPOLL_RESPONSE))) { 380 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 381 printk(KERN_DEBUG "STA %pM aid %d: PS buffer (entries " 382 "before %d)\n", 383 sta->sta.addr, sta->sta.aid, 384 skb_queue_len(&sta->ps_tx_buf)); 385 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 386 if (tx->local->total_ps_buffered >= TOTAL_MAX_TX_BUFFER) 387 purge_old_ps_buffers(tx->local); 388 if (skb_queue_len(&sta->ps_tx_buf) >= STA_MAX_TX_BUFFER) { 389 struct sk_buff *old = skb_dequeue(&sta->ps_tx_buf); 390 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 391 if (net_ratelimit()) { 392 printk(KERN_DEBUG "%s: STA %pM TX " 393 "buffer full - dropping oldest frame\n", 394 tx->dev->name, sta->sta.addr); 395 } 396 #endif 397 dev_kfree_skb(old); 398 } else 399 tx->local->total_ps_buffered++; 400 401 /* Queue frame to be sent after STA sends an PS Poll frame */ 402 if (skb_queue_empty(&sta->ps_tx_buf)) 403 sta_info_set_tim_bit(sta); 404 405 info->control.jiffies = jiffies; 406 info->control.vif = &tx->sdata->vif; 407 info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING; 408 skb_queue_tail(&sta->ps_tx_buf, tx->skb); 409 return TX_QUEUED; 410 } 411 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 412 else if (unlikely(test_sta_flags(sta, WLAN_STA_PS))) { 413 printk(KERN_DEBUG "%s: STA %pM in PS mode, but pspoll " 414 "set -> send frame\n", tx->dev->name, 415 sta->sta.addr); 416 } 417 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 418 419 return TX_CONTINUE; 420 } 421 422 static ieee80211_tx_result debug_noinline 423 ieee80211_tx_h_ps_buf(struct ieee80211_tx_data *tx) 424 { 425 if (unlikely(tx->flags & IEEE80211_TX_PS_BUFFERED)) 426 return TX_CONTINUE; 427 428 if (tx->flags & IEEE80211_TX_UNICAST) 429 return ieee80211_tx_h_unicast_ps_buf(tx); 430 else 431 return ieee80211_tx_h_multicast_ps_buf(tx); 432 } 433 434 static ieee80211_tx_result debug_noinline 435 ieee80211_tx_h_select_key(struct ieee80211_tx_data *tx) 436 { 437 struct ieee80211_key *key = NULL; 438 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb); 439 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data; 440 441 if (unlikely(info->flags & IEEE80211_TX_INTFL_DONT_ENCRYPT)) 442 tx->key = NULL; 443 else if (tx->sta && (key = rcu_dereference(tx->sta->key))) 444 tx->key = key; 445 else if (ieee80211_is_mgmt(hdr->frame_control) && 446 (key = rcu_dereference(tx->sdata->default_mgmt_key))) 447 tx->key = key; 448 else if ((key = rcu_dereference(tx->sdata->default_key))) 449 tx->key = key; 450 else if (tx->sdata->drop_unencrypted && 451 (tx->skb->protocol != cpu_to_be16(ETH_P_PAE)) && 452 !(info->flags & IEEE80211_TX_CTL_INJECTED) && 453 (!ieee80211_is_robust_mgmt_frame(hdr) || 454 (ieee80211_is_action(hdr->frame_control) && 455 tx->sta && test_sta_flags(tx->sta, WLAN_STA_MFP)))) { 456 I802_DEBUG_INC(tx->local->tx_handlers_drop_unencrypted); 457 return TX_DROP; 458 } else 459 tx->key = NULL; 460 461 if (tx->key) { 462 tx->key->tx_rx_count++; 463 /* TODO: add threshold stuff again */ 464 465 switch (tx->key->conf.alg) { 466 case ALG_WEP: 467 if (ieee80211_is_auth(hdr->frame_control)) 468 break; 469 case ALG_TKIP: 470 if (!ieee80211_is_data_present(hdr->frame_control)) 471 tx->key = NULL; 472 break; 473 case ALG_CCMP: 474 if (!ieee80211_is_data_present(hdr->frame_control) && 475 !ieee80211_use_mfp(hdr->frame_control, tx->sta, 476 tx->skb)) 477 tx->key = NULL; 478 break; 479 case ALG_AES_CMAC: 480 if (!ieee80211_is_mgmt(hdr->frame_control)) 481 tx->key = NULL; 482 break; 483 } 484 } 485 486 if (!tx->key || !(tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE)) 487 info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT; 488 489 return TX_CONTINUE; 490 } 491 492 static ieee80211_tx_result debug_noinline 493 ieee80211_tx_h_rate_ctrl(struct ieee80211_tx_data *tx) 494 { 495 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb); 496 struct ieee80211_hdr *hdr = (void *)tx->skb->data; 497 struct ieee80211_supported_band *sband; 498 struct ieee80211_rate *rate; 499 int i, len; 500 bool inval = false, rts = false, short_preamble = false; 501 struct ieee80211_tx_rate_control txrc; 502 u32 sta_flags; 503 504 memset(&txrc, 0, sizeof(txrc)); 505 506 sband = tx->local->hw.wiphy->bands[tx->channel->band]; 507 508 len = min_t(int, tx->skb->len + FCS_LEN, 509 tx->local->hw.wiphy->frag_threshold); 510 511 /* set up the tx rate control struct we give the RC algo */ 512 txrc.hw = local_to_hw(tx->local); 513 txrc.sband = sband; 514 txrc.bss_conf = &tx->sdata->vif.bss_conf; 515 txrc.skb = tx->skb; 516 txrc.reported_rate.idx = -1; 517 txrc.max_rate_idx = tx->sdata->max_ratectrl_rateidx; 518 519 /* set up RTS protection if desired */ 520 if (len > tx->local->hw.wiphy->rts_threshold) { 521 txrc.rts = rts = true; 522 } 523 524 /* 525 * Use short preamble if the BSS can handle it, but not for 526 * management frames unless we know the receiver can handle 527 * that -- the management frame might be to a station that 528 * just wants a probe response. 529 */ 530 if (tx->sdata->vif.bss_conf.use_short_preamble && 531 (ieee80211_is_data(hdr->frame_control) || 532 (tx->sta && test_sta_flags(tx->sta, WLAN_STA_SHORT_PREAMBLE)))) 533 txrc.short_preamble = short_preamble = true; 534 535 sta_flags = tx->sta ? get_sta_flags(tx->sta) : 0; 536 537 /* 538 * Lets not bother rate control if we're associated and cannot 539 * talk to the sta. This should not happen. 540 */ 541 if (WARN(test_bit(SCAN_SW_SCANNING, &tx->local->scanning) && 542 (sta_flags & WLAN_STA_ASSOC) && 543 !rate_usable_index_exists(sband, &tx->sta->sta), 544 "%s: Dropped data frame as no usable bitrate found while " 545 "scanning and associated. Target station: " 546 "%pM on %d GHz band\n", 547 tx->dev->name, hdr->addr1, 548 tx->channel->band ? 5 : 2)) 549 return TX_DROP; 550 551 /* 552 * If we're associated with the sta at this point we know we can at 553 * least send the frame at the lowest bit rate. 554 */ 555 rate_control_get_rate(tx->sdata, tx->sta, &txrc); 556 557 if (unlikely(info->control.rates[0].idx < 0)) 558 return TX_DROP; 559 560 if (txrc.reported_rate.idx < 0) 561 txrc.reported_rate = info->control.rates[0]; 562 563 if (tx->sta) 564 tx->sta->last_tx_rate = txrc.reported_rate; 565 566 if (unlikely(!info->control.rates[0].count)) 567 info->control.rates[0].count = 1; 568 569 if (WARN_ON_ONCE((info->control.rates[0].count > 1) && 570 (info->flags & IEEE80211_TX_CTL_NO_ACK))) 571 info->control.rates[0].count = 1; 572 573 if (is_multicast_ether_addr(hdr->addr1)) { 574 /* 575 * XXX: verify the rate is in the basic rateset 576 */ 577 return TX_CONTINUE; 578 } 579 580 /* 581 * set up the RTS/CTS rate as the fastest basic rate 582 * that is not faster than the data rate 583 * 584 * XXX: Should this check all retry rates? 585 */ 586 if (!(info->control.rates[0].flags & IEEE80211_TX_RC_MCS)) { 587 s8 baserate = 0; 588 589 rate = &sband->bitrates[info->control.rates[0].idx]; 590 591 for (i = 0; i < sband->n_bitrates; i++) { 592 /* must be a basic rate */ 593 if (!(tx->sdata->vif.bss_conf.basic_rates & BIT(i))) 594 continue; 595 /* must not be faster than the data rate */ 596 if (sband->bitrates[i].bitrate > rate->bitrate) 597 continue; 598 /* maximum */ 599 if (sband->bitrates[baserate].bitrate < 600 sband->bitrates[i].bitrate) 601 baserate = i; 602 } 603 604 info->control.rts_cts_rate_idx = baserate; 605 } 606 607 for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) { 608 /* 609 * make sure there's no valid rate following 610 * an invalid one, just in case drivers don't 611 * take the API seriously to stop at -1. 612 */ 613 if (inval) { 614 info->control.rates[i].idx = -1; 615 continue; 616 } 617 if (info->control.rates[i].idx < 0) { 618 inval = true; 619 continue; 620 } 621 622 /* 623 * For now assume MCS is already set up correctly, this 624 * needs to be fixed. 625 */ 626 if (info->control.rates[i].flags & IEEE80211_TX_RC_MCS) { 627 WARN_ON(info->control.rates[i].idx > 76); 628 continue; 629 } 630 631 /* set up RTS protection if desired */ 632 if (rts) 633 info->control.rates[i].flags |= 634 IEEE80211_TX_RC_USE_RTS_CTS; 635 636 /* RC is busted */ 637 if (WARN_ON_ONCE(info->control.rates[i].idx >= 638 sband->n_bitrates)) { 639 info->control.rates[i].idx = -1; 640 continue; 641 } 642 643 rate = &sband->bitrates[info->control.rates[i].idx]; 644 645 /* set up short preamble */ 646 if (short_preamble && 647 rate->flags & IEEE80211_RATE_SHORT_PREAMBLE) 648 info->control.rates[i].flags |= 649 IEEE80211_TX_RC_USE_SHORT_PREAMBLE; 650 651 /* set up G protection */ 652 if (!rts && tx->sdata->vif.bss_conf.use_cts_prot && 653 rate->flags & IEEE80211_RATE_ERP_G) 654 info->control.rates[i].flags |= 655 IEEE80211_TX_RC_USE_CTS_PROTECT; 656 } 657 658 return TX_CONTINUE; 659 } 660 661 static ieee80211_tx_result debug_noinline 662 ieee80211_tx_h_misc(struct ieee80211_tx_data *tx) 663 { 664 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb); 665 666 if (tx->sta) 667 info->control.sta = &tx->sta->sta; 668 669 return TX_CONTINUE; 670 } 671 672 static ieee80211_tx_result debug_noinline 673 ieee80211_tx_h_sequence(struct ieee80211_tx_data *tx) 674 { 675 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb); 676 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data; 677 u16 *seq; 678 u8 *qc; 679 int tid; 680 681 /* 682 * Packet injection may want to control the sequence 683 * number, if we have no matching interface then we 684 * neither assign one ourselves nor ask the driver to. 685 */ 686 if (unlikely(info->control.vif->type == NL80211_IFTYPE_MONITOR)) 687 return TX_CONTINUE; 688 689 if (unlikely(ieee80211_is_ctl(hdr->frame_control))) 690 return TX_CONTINUE; 691 692 if (ieee80211_hdrlen(hdr->frame_control) < 24) 693 return TX_CONTINUE; 694 695 /* 696 * Anything but QoS data that has a sequence number field 697 * (is long enough) gets a sequence number from the global 698 * counter. 699 */ 700 if (!ieee80211_is_data_qos(hdr->frame_control)) { 701 /* driver should assign sequence number */ 702 info->flags |= IEEE80211_TX_CTL_ASSIGN_SEQ; 703 /* for pure STA mode without beacons, we can do it */ 704 hdr->seq_ctrl = cpu_to_le16(tx->sdata->sequence_number); 705 tx->sdata->sequence_number += 0x10; 706 return TX_CONTINUE; 707 } 708 709 /* 710 * This should be true for injected/management frames only, for 711 * management frames we have set the IEEE80211_TX_CTL_ASSIGN_SEQ 712 * above since they are not QoS-data frames. 713 */ 714 if (!tx->sta) 715 return TX_CONTINUE; 716 717 /* include per-STA, per-TID sequence counter */ 718 719 qc = ieee80211_get_qos_ctl(hdr); 720 tid = *qc & IEEE80211_QOS_CTL_TID_MASK; 721 seq = &tx->sta->tid_seq[tid]; 722 723 hdr->seq_ctrl = cpu_to_le16(*seq); 724 725 /* Increase the sequence number. */ 726 *seq = (*seq + 0x10) & IEEE80211_SCTL_SEQ; 727 728 return TX_CONTINUE; 729 } 730 731 static int ieee80211_fragment(struct ieee80211_local *local, 732 struct sk_buff *skb, int hdrlen, 733 int frag_threshold) 734 { 735 struct sk_buff *tail = skb, *tmp; 736 int per_fragm = frag_threshold - hdrlen - FCS_LEN; 737 int pos = hdrlen + per_fragm; 738 int rem = skb->len - hdrlen - per_fragm; 739 740 if (WARN_ON(rem < 0)) 741 return -EINVAL; 742 743 while (rem) { 744 int fraglen = per_fragm; 745 746 if (fraglen > rem) 747 fraglen = rem; 748 rem -= fraglen; 749 tmp = dev_alloc_skb(local->tx_headroom + 750 frag_threshold + 751 IEEE80211_ENCRYPT_HEADROOM + 752 IEEE80211_ENCRYPT_TAILROOM); 753 if (!tmp) 754 return -ENOMEM; 755 tail->next = tmp; 756 tail = tmp; 757 skb_reserve(tmp, local->tx_headroom + 758 IEEE80211_ENCRYPT_HEADROOM); 759 /* copy control information */ 760 memcpy(tmp->cb, skb->cb, sizeof(tmp->cb)); 761 skb_copy_queue_mapping(tmp, skb); 762 tmp->priority = skb->priority; 763 tmp->dev = skb->dev; 764 765 /* copy header and data */ 766 memcpy(skb_put(tmp, hdrlen), skb->data, hdrlen); 767 memcpy(skb_put(tmp, fraglen), skb->data + pos, fraglen); 768 769 pos += fraglen; 770 } 771 772 skb->len = hdrlen + per_fragm; 773 return 0; 774 } 775 776 static ieee80211_tx_result debug_noinline 777 ieee80211_tx_h_fragment(struct ieee80211_tx_data *tx) 778 { 779 struct sk_buff *skb = tx->skb; 780 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 781 struct ieee80211_hdr *hdr = (void *)skb->data; 782 int frag_threshold = tx->local->hw.wiphy->frag_threshold; 783 int hdrlen; 784 int fragnum; 785 786 if (!(tx->flags & IEEE80211_TX_FRAGMENTED)) 787 return TX_CONTINUE; 788 789 /* 790 * Warn when submitting a fragmented A-MPDU frame and drop it. 791 * This scenario is handled in ieee80211_tx_prepare but extra 792 * caution taken here as fragmented ampdu may cause Tx stop. 793 */ 794 if (WARN_ON(info->flags & IEEE80211_TX_CTL_AMPDU)) 795 return TX_DROP; 796 797 hdrlen = ieee80211_hdrlen(hdr->frame_control); 798 799 /* internal error, why is TX_FRAGMENTED set? */ 800 if (WARN_ON(skb->len + FCS_LEN <= frag_threshold)) 801 return TX_DROP; 802 803 /* 804 * Now fragment the frame. This will allocate all the fragments and 805 * chain them (using skb as the first fragment) to skb->next. 806 * During transmission, we will remove the successfully transmitted 807 * fragments from this list. When the low-level driver rejects one 808 * of the fragments then we will simply pretend to accept the skb 809 * but store it away as pending. 810 */ 811 if (ieee80211_fragment(tx->local, skb, hdrlen, frag_threshold)) 812 return TX_DROP; 813 814 /* update duration/seq/flags of fragments */ 815 fragnum = 0; 816 do { 817 int next_len; 818 const __le16 morefrags = cpu_to_le16(IEEE80211_FCTL_MOREFRAGS); 819 820 hdr = (void *)skb->data; 821 info = IEEE80211_SKB_CB(skb); 822 823 if (skb->next) { 824 hdr->frame_control |= morefrags; 825 next_len = skb->next->len; 826 /* 827 * No multi-rate retries for fragmented frames, that 828 * would completely throw off the NAV at other STAs. 829 */ 830 info->control.rates[1].idx = -1; 831 info->control.rates[2].idx = -1; 832 info->control.rates[3].idx = -1; 833 info->control.rates[4].idx = -1; 834 BUILD_BUG_ON(IEEE80211_TX_MAX_RATES != 5); 835 info->flags &= ~IEEE80211_TX_CTL_RATE_CTRL_PROBE; 836 } else { 837 hdr->frame_control &= ~morefrags; 838 next_len = 0; 839 } 840 hdr->duration_id = ieee80211_duration(tx, 0, next_len); 841 hdr->seq_ctrl |= cpu_to_le16(fragnum & IEEE80211_SCTL_FRAG); 842 fragnum++; 843 } while ((skb = skb->next)); 844 845 return TX_CONTINUE; 846 } 847 848 static ieee80211_tx_result debug_noinline 849 ieee80211_tx_h_stats(struct ieee80211_tx_data *tx) 850 { 851 struct sk_buff *skb = tx->skb; 852 853 if (!tx->sta) 854 return TX_CONTINUE; 855 856 tx->sta->tx_packets++; 857 do { 858 tx->sta->tx_fragments++; 859 tx->sta->tx_bytes += skb->len; 860 } while ((skb = skb->next)); 861 862 return TX_CONTINUE; 863 } 864 865 static ieee80211_tx_result debug_noinline 866 ieee80211_tx_h_encrypt(struct ieee80211_tx_data *tx) 867 { 868 if (!tx->key) 869 return TX_CONTINUE; 870 871 switch (tx->key->conf.alg) { 872 case ALG_WEP: 873 return ieee80211_crypto_wep_encrypt(tx); 874 case ALG_TKIP: 875 return ieee80211_crypto_tkip_encrypt(tx); 876 case ALG_CCMP: 877 return ieee80211_crypto_ccmp_encrypt(tx); 878 case ALG_AES_CMAC: 879 return ieee80211_crypto_aes_cmac_encrypt(tx); 880 } 881 882 /* not reached */ 883 WARN_ON(1); 884 return TX_DROP; 885 } 886 887 static ieee80211_tx_result debug_noinline 888 ieee80211_tx_h_calculate_duration(struct ieee80211_tx_data *tx) 889 { 890 struct sk_buff *skb = tx->skb; 891 struct ieee80211_hdr *hdr; 892 int next_len; 893 bool group_addr; 894 895 do { 896 hdr = (void *) skb->data; 897 if (unlikely(ieee80211_is_pspoll(hdr->frame_control))) 898 break; /* must not overwrite AID */ 899 next_len = skb->next ? skb->next->len : 0; 900 group_addr = is_multicast_ether_addr(hdr->addr1); 901 902 hdr->duration_id = 903 ieee80211_duration(tx, group_addr, next_len); 904 } while ((skb = skb->next)); 905 906 return TX_CONTINUE; 907 } 908 909 /* actual transmit path */ 910 911 /* 912 * deal with packet injection down monitor interface 913 * with Radiotap Header -- only called for monitor mode interface 914 */ 915 static bool __ieee80211_parse_tx_radiotap(struct ieee80211_tx_data *tx, 916 struct sk_buff *skb) 917 { 918 /* 919 * this is the moment to interpret and discard the radiotap header that 920 * must be at the start of the packet injected in Monitor mode 921 * 922 * Need to take some care with endian-ness since radiotap 923 * args are little-endian 924 */ 925 926 struct ieee80211_radiotap_iterator iterator; 927 struct ieee80211_radiotap_header *rthdr = 928 (struct ieee80211_radiotap_header *) skb->data; 929 struct ieee80211_supported_band *sband; 930 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 931 int ret = ieee80211_radiotap_iterator_init(&iterator, rthdr, skb->len); 932 933 sband = tx->local->hw.wiphy->bands[tx->channel->band]; 934 935 info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT; 936 tx->flags &= ~IEEE80211_TX_FRAGMENTED; 937 938 /* 939 * for every radiotap entry that is present 940 * (ieee80211_radiotap_iterator_next returns -ENOENT when no more 941 * entries present, or -EINVAL on error) 942 */ 943 944 while (!ret) { 945 ret = ieee80211_radiotap_iterator_next(&iterator); 946 947 if (ret) 948 continue; 949 950 /* see if this argument is something we can use */ 951 switch (iterator.this_arg_index) { 952 /* 953 * You must take care when dereferencing iterator.this_arg 954 * for multibyte types... the pointer is not aligned. Use 955 * get_unaligned((type *)iterator.this_arg) to dereference 956 * iterator.this_arg for type "type" safely on all arches. 957 */ 958 case IEEE80211_RADIOTAP_FLAGS: 959 if (*iterator.this_arg & IEEE80211_RADIOTAP_F_FCS) { 960 /* 961 * this indicates that the skb we have been 962 * handed has the 32-bit FCS CRC at the end... 963 * we should react to that by snipping it off 964 * because it will be recomputed and added 965 * on transmission 966 */ 967 if (skb->len < (iterator.max_length + FCS_LEN)) 968 return false; 969 970 skb_trim(skb, skb->len - FCS_LEN); 971 } 972 if (*iterator.this_arg & IEEE80211_RADIOTAP_F_WEP) 973 info->flags &= ~IEEE80211_TX_INTFL_DONT_ENCRYPT; 974 if (*iterator.this_arg & IEEE80211_RADIOTAP_F_FRAG) 975 tx->flags |= IEEE80211_TX_FRAGMENTED; 976 break; 977 978 /* 979 * Please update the file 980 * Documentation/networking/mac80211-injection.txt 981 * when parsing new fields here. 982 */ 983 984 default: 985 break; 986 } 987 } 988 989 if (ret != -ENOENT) /* ie, if we didn't simply run out of fields */ 990 return false; 991 992 /* 993 * remove the radiotap header 994 * iterator->max_length was sanity-checked against 995 * skb->len by iterator init 996 */ 997 skb_pull(skb, iterator.max_length); 998 999 return true; 1000 } 1001 1002 /* 1003 * initialises @tx 1004 */ 1005 static ieee80211_tx_result 1006 ieee80211_tx_prepare(struct ieee80211_sub_if_data *sdata, 1007 struct ieee80211_tx_data *tx, 1008 struct sk_buff *skb) 1009 { 1010 struct ieee80211_local *local = sdata->local; 1011 struct ieee80211_hdr *hdr; 1012 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 1013 int hdrlen, tid; 1014 u8 *qc, *state; 1015 bool queued = false; 1016 1017 memset(tx, 0, sizeof(*tx)); 1018 tx->skb = skb; 1019 tx->dev = sdata->dev; /* use original interface */ 1020 tx->local = local; 1021 tx->sdata = sdata; 1022 tx->channel = local->hw.conf.channel; 1023 /* 1024 * Set this flag (used below to indicate "automatic fragmentation"), 1025 * it will be cleared/left by radiotap as desired. 1026 */ 1027 tx->flags |= IEEE80211_TX_FRAGMENTED; 1028 1029 /* process and remove the injection radiotap header */ 1030 if (unlikely(info->flags & IEEE80211_TX_CTL_INJECTED)) { 1031 if (!__ieee80211_parse_tx_radiotap(tx, skb)) 1032 return TX_DROP; 1033 1034 /* 1035 * __ieee80211_parse_tx_radiotap has now removed 1036 * the radiotap header that was present and pre-filled 1037 * 'tx' with tx control information. 1038 */ 1039 } 1040 1041 /* 1042 * If this flag is set to true anywhere, and we get here, 1043 * we are doing the needed processing, so remove the flag 1044 * now. 1045 */ 1046 info->flags &= ~IEEE80211_TX_INTFL_NEED_TXPROCESSING; 1047 1048 hdr = (struct ieee80211_hdr *) skb->data; 1049 1050 tx->sta = sta_info_get(local, hdr->addr1); 1051 1052 if (tx->sta && ieee80211_is_data_qos(hdr->frame_control) && 1053 (local->hw.flags & IEEE80211_HW_AMPDU_AGGREGATION)) { 1054 unsigned long flags; 1055 struct tid_ampdu_tx *tid_tx; 1056 1057 qc = ieee80211_get_qos_ctl(hdr); 1058 tid = *qc & IEEE80211_QOS_CTL_TID_MASK; 1059 1060 spin_lock_irqsave(&tx->sta->lock, flags); 1061 /* 1062 * XXX: This spinlock could be fairly expensive, but see the 1063 * comment in agg-tx.c:ieee80211_agg_tx_operational(). 1064 * One way to solve this would be to do something RCU-like 1065 * for managing the tid_tx struct and using atomic bitops 1066 * for the actual state -- by introducing an actual 1067 * 'operational' bit that would be possible. It would 1068 * require changing ieee80211_agg_tx_operational() to 1069 * set that bit, and changing the way tid_tx is managed 1070 * everywhere, including races between that bit and 1071 * tid_tx going away (tid_tx being added can be easily 1072 * committed to memory before the 'operational' bit). 1073 */ 1074 tid_tx = tx->sta->ampdu_mlme.tid_tx[tid]; 1075 state = &tx->sta->ampdu_mlme.tid_state_tx[tid]; 1076 if (*state == HT_AGG_STATE_OPERATIONAL) { 1077 info->flags |= IEEE80211_TX_CTL_AMPDU; 1078 } else if (*state != HT_AGG_STATE_IDLE) { 1079 /* in progress */ 1080 queued = true; 1081 info->control.vif = &sdata->vif; 1082 info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING; 1083 __skb_queue_tail(&tid_tx->pending, skb); 1084 } 1085 spin_unlock_irqrestore(&tx->sta->lock, flags); 1086 1087 if (unlikely(queued)) 1088 return TX_QUEUED; 1089 } 1090 1091 if (is_multicast_ether_addr(hdr->addr1)) { 1092 tx->flags &= ~IEEE80211_TX_UNICAST; 1093 info->flags |= IEEE80211_TX_CTL_NO_ACK; 1094 } else { 1095 tx->flags |= IEEE80211_TX_UNICAST; 1096 if (unlikely(local->wifi_wme_noack_test)) 1097 info->flags |= IEEE80211_TX_CTL_NO_ACK; 1098 else 1099 info->flags &= ~IEEE80211_TX_CTL_NO_ACK; 1100 } 1101 1102 if (tx->flags & IEEE80211_TX_FRAGMENTED) { 1103 if ((tx->flags & IEEE80211_TX_UNICAST) && 1104 skb->len + FCS_LEN > local->hw.wiphy->frag_threshold && 1105 !(info->flags & IEEE80211_TX_CTL_AMPDU)) 1106 tx->flags |= IEEE80211_TX_FRAGMENTED; 1107 else 1108 tx->flags &= ~IEEE80211_TX_FRAGMENTED; 1109 } 1110 1111 if (!tx->sta) 1112 info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT; 1113 else if (test_and_clear_sta_flags(tx->sta, WLAN_STA_CLEAR_PS_FILT)) 1114 info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT; 1115 1116 hdrlen = ieee80211_hdrlen(hdr->frame_control); 1117 if (skb->len > hdrlen + sizeof(rfc1042_header) + 2) { 1118 u8 *pos = &skb->data[hdrlen + sizeof(rfc1042_header)]; 1119 tx->ethertype = (pos[0] << 8) | pos[1]; 1120 } 1121 info->flags |= IEEE80211_TX_CTL_FIRST_FRAGMENT; 1122 1123 return TX_CONTINUE; 1124 } 1125 1126 static int __ieee80211_tx(struct ieee80211_local *local, 1127 struct sk_buff **skbp, 1128 struct sta_info *sta, 1129 bool txpending) 1130 { 1131 struct sk_buff *skb = *skbp, *next; 1132 struct ieee80211_tx_info *info; 1133 struct ieee80211_sub_if_data *sdata; 1134 unsigned long flags; 1135 int ret, len; 1136 bool fragm = false; 1137 1138 while (skb) { 1139 int q = skb_get_queue_mapping(skb); 1140 1141 spin_lock_irqsave(&local->queue_stop_reason_lock, flags); 1142 ret = IEEE80211_TX_OK; 1143 if (local->queue_stop_reasons[q] || 1144 (!txpending && !skb_queue_empty(&local->pending[q]))) 1145 ret = IEEE80211_TX_PENDING; 1146 spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags); 1147 if (ret != IEEE80211_TX_OK) 1148 return ret; 1149 1150 info = IEEE80211_SKB_CB(skb); 1151 1152 if (fragm) 1153 info->flags &= ~(IEEE80211_TX_CTL_CLEAR_PS_FILT | 1154 IEEE80211_TX_CTL_FIRST_FRAGMENT); 1155 1156 next = skb->next; 1157 len = skb->len; 1158 1159 if (next) 1160 info->flags |= IEEE80211_TX_CTL_MORE_FRAMES; 1161 1162 sdata = vif_to_sdata(info->control.vif); 1163 1164 switch (sdata->vif.type) { 1165 case NL80211_IFTYPE_MONITOR: 1166 info->control.vif = NULL; 1167 break; 1168 case NL80211_IFTYPE_AP_VLAN: 1169 info->control.vif = &container_of(sdata->bss, 1170 struct ieee80211_sub_if_data, u.ap)->vif; 1171 break; 1172 default: 1173 /* keep */ 1174 break; 1175 } 1176 1177 ret = drv_tx(local, skb); 1178 if (WARN_ON(ret != NETDEV_TX_OK && skb->len != len)) { 1179 dev_kfree_skb(skb); 1180 ret = NETDEV_TX_OK; 1181 } 1182 if (ret != NETDEV_TX_OK) { 1183 info->control.vif = &sdata->vif; 1184 return IEEE80211_TX_AGAIN; 1185 } 1186 1187 *skbp = skb = next; 1188 ieee80211_led_tx(local, 1); 1189 fragm = true; 1190 } 1191 1192 return IEEE80211_TX_OK; 1193 } 1194 1195 /* 1196 * Invoke TX handlers, return 0 on success and non-zero if the 1197 * frame was dropped or queued. 1198 */ 1199 static int invoke_tx_handlers(struct ieee80211_tx_data *tx) 1200 { 1201 struct sk_buff *skb = tx->skb; 1202 ieee80211_tx_result res = TX_DROP; 1203 1204 #define CALL_TXH(txh) \ 1205 res = txh(tx); \ 1206 if (res != TX_CONTINUE) \ 1207 goto txh_done; 1208 1209 CALL_TXH(ieee80211_tx_h_check_assoc) 1210 CALL_TXH(ieee80211_tx_h_ps_buf) 1211 CALL_TXH(ieee80211_tx_h_select_key) 1212 CALL_TXH(ieee80211_tx_h_michael_mic_add) 1213 CALL_TXH(ieee80211_tx_h_rate_ctrl) 1214 CALL_TXH(ieee80211_tx_h_misc) 1215 CALL_TXH(ieee80211_tx_h_sequence) 1216 CALL_TXH(ieee80211_tx_h_fragment) 1217 /* handlers after fragment must be aware of tx info fragmentation! */ 1218 CALL_TXH(ieee80211_tx_h_stats) 1219 CALL_TXH(ieee80211_tx_h_encrypt) 1220 CALL_TXH(ieee80211_tx_h_calculate_duration) 1221 #undef CALL_TXH 1222 1223 txh_done: 1224 if (unlikely(res == TX_DROP)) { 1225 I802_DEBUG_INC(tx->local->tx_handlers_drop); 1226 while (skb) { 1227 struct sk_buff *next; 1228 1229 next = skb->next; 1230 dev_kfree_skb(skb); 1231 skb = next; 1232 } 1233 return -1; 1234 } else if (unlikely(res == TX_QUEUED)) { 1235 I802_DEBUG_INC(tx->local->tx_handlers_queued); 1236 return -1; 1237 } 1238 1239 return 0; 1240 } 1241 1242 static void ieee80211_tx(struct ieee80211_sub_if_data *sdata, 1243 struct sk_buff *skb, bool txpending) 1244 { 1245 struct ieee80211_local *local = sdata->local; 1246 struct ieee80211_tx_data tx; 1247 ieee80211_tx_result res_prepare; 1248 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 1249 struct sk_buff *next; 1250 unsigned long flags; 1251 int ret, retries; 1252 u16 queue; 1253 1254 queue = skb_get_queue_mapping(skb); 1255 1256 if (unlikely(skb->len < 10)) { 1257 dev_kfree_skb(skb); 1258 return; 1259 } 1260 1261 rcu_read_lock(); 1262 1263 /* initialises tx */ 1264 res_prepare = ieee80211_tx_prepare(sdata, &tx, skb); 1265 1266 if (unlikely(res_prepare == TX_DROP)) { 1267 dev_kfree_skb(skb); 1268 rcu_read_unlock(); 1269 return; 1270 } else if (unlikely(res_prepare == TX_QUEUED)) { 1271 rcu_read_unlock(); 1272 return; 1273 } 1274 1275 tx.channel = local->hw.conf.channel; 1276 info->band = tx.channel->band; 1277 1278 if (invoke_tx_handlers(&tx)) 1279 goto out; 1280 1281 retries = 0; 1282 retry: 1283 ret = __ieee80211_tx(local, &tx.skb, tx.sta, txpending); 1284 switch (ret) { 1285 case IEEE80211_TX_OK: 1286 break; 1287 case IEEE80211_TX_AGAIN: 1288 /* 1289 * Since there are no fragmented frames on A-MPDU 1290 * queues, there's no reason for a driver to reject 1291 * a frame there, warn and drop it. 1292 */ 1293 if (WARN_ON(info->flags & IEEE80211_TX_CTL_AMPDU)) 1294 goto drop; 1295 /* fall through */ 1296 case IEEE80211_TX_PENDING: 1297 skb = tx.skb; 1298 1299 spin_lock_irqsave(&local->queue_stop_reason_lock, flags); 1300 1301 if (local->queue_stop_reasons[queue] || 1302 !skb_queue_empty(&local->pending[queue])) { 1303 /* 1304 * if queue is stopped, queue up frames for later 1305 * transmission from the tasklet 1306 */ 1307 do { 1308 next = skb->next; 1309 skb->next = NULL; 1310 if (unlikely(txpending)) 1311 __skb_queue_head(&local->pending[queue], 1312 skb); 1313 else 1314 __skb_queue_tail(&local->pending[queue], 1315 skb); 1316 } while ((skb = next)); 1317 1318 spin_unlock_irqrestore(&local->queue_stop_reason_lock, 1319 flags); 1320 } else { 1321 /* 1322 * otherwise retry, but this is a race condition or 1323 * a driver bug (which we warn about if it persists) 1324 */ 1325 spin_unlock_irqrestore(&local->queue_stop_reason_lock, 1326 flags); 1327 1328 retries++; 1329 if (WARN(retries > 10, "tx refused but queue active\n")) 1330 goto drop; 1331 goto retry; 1332 } 1333 } 1334 out: 1335 rcu_read_unlock(); 1336 return; 1337 1338 drop: 1339 rcu_read_unlock(); 1340 1341 skb = tx.skb; 1342 while (skb) { 1343 next = skb->next; 1344 dev_kfree_skb(skb); 1345 skb = next; 1346 } 1347 } 1348 1349 /* device xmit handlers */ 1350 1351 static int ieee80211_skb_resize(struct ieee80211_local *local, 1352 struct sk_buff *skb, 1353 int head_need, bool may_encrypt) 1354 { 1355 int tail_need = 0; 1356 1357 /* 1358 * This could be optimised, devices that do full hardware 1359 * crypto (including TKIP MMIC) need no tailroom... But we 1360 * have no drivers for such devices currently. 1361 */ 1362 if (may_encrypt) { 1363 tail_need = IEEE80211_ENCRYPT_TAILROOM; 1364 tail_need -= skb_tailroom(skb); 1365 tail_need = max_t(int, tail_need, 0); 1366 } 1367 1368 if (head_need || tail_need) { 1369 /* Sorry. Can't account for this any more */ 1370 skb_orphan(skb); 1371 } 1372 1373 if (skb_header_cloned(skb)) 1374 I802_DEBUG_INC(local->tx_expand_skb_head_cloned); 1375 else 1376 I802_DEBUG_INC(local->tx_expand_skb_head); 1377 1378 if (pskb_expand_head(skb, head_need, tail_need, GFP_ATOMIC)) { 1379 printk(KERN_DEBUG "%s: failed to reallocate TX buffer\n", 1380 wiphy_name(local->hw.wiphy)); 1381 return -ENOMEM; 1382 } 1383 1384 /* update truesize too */ 1385 skb->truesize += head_need + tail_need; 1386 1387 return 0; 1388 } 1389 1390 static void ieee80211_xmit(struct ieee80211_sub_if_data *sdata, 1391 struct sk_buff *skb) 1392 { 1393 struct ieee80211_local *local = sdata->local; 1394 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 1395 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 1396 struct ieee80211_sub_if_data *tmp_sdata; 1397 int headroom; 1398 bool may_encrypt; 1399 1400 dev_hold(sdata->dev); 1401 1402 if ((local->hw.flags & IEEE80211_HW_PS_NULLFUNC_STACK) && 1403 local->hw.conf.dynamic_ps_timeout > 0 && 1404 !(local->scanning) && local->ps_sdata) { 1405 if (local->hw.conf.flags & IEEE80211_CONF_PS) { 1406 ieee80211_stop_queues_by_reason(&local->hw, 1407 IEEE80211_QUEUE_STOP_REASON_PS); 1408 ieee80211_queue_work(&local->hw, 1409 &local->dynamic_ps_disable_work); 1410 } 1411 1412 mod_timer(&local->dynamic_ps_timer, jiffies + 1413 msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout)); 1414 } 1415 1416 info->flags |= IEEE80211_TX_CTL_REQ_TX_STATUS; 1417 1418 if (unlikely(sdata->vif.type == NL80211_IFTYPE_MONITOR)) { 1419 int hdrlen; 1420 u16 len_rthdr; 1421 1422 info->flags |= IEEE80211_TX_CTL_INJECTED; 1423 1424 len_rthdr = ieee80211_get_radiotap_len(skb->data); 1425 hdr = (struct ieee80211_hdr *)(skb->data + len_rthdr); 1426 hdrlen = ieee80211_hdrlen(hdr->frame_control); 1427 1428 /* check the header is complete in the frame */ 1429 if (likely(skb->len >= len_rthdr + hdrlen)) { 1430 /* 1431 * We process outgoing injected frames that have a 1432 * local address we handle as though they are our 1433 * own frames. 1434 * This code here isn't entirely correct, the local 1435 * MAC address is not necessarily enough to find 1436 * the interface to use; for that proper VLAN/WDS 1437 * support we will need a different mechanism. 1438 */ 1439 1440 rcu_read_lock(); 1441 list_for_each_entry_rcu(tmp_sdata, &local->interfaces, 1442 list) { 1443 if (!netif_running(tmp_sdata->dev)) 1444 continue; 1445 if (tmp_sdata->vif.type != NL80211_IFTYPE_AP) 1446 continue; 1447 if (compare_ether_addr(tmp_sdata->dev->dev_addr, 1448 hdr->addr2)) { 1449 dev_hold(tmp_sdata->dev); 1450 dev_put(sdata->dev); 1451 sdata = tmp_sdata; 1452 break; 1453 } 1454 } 1455 rcu_read_unlock(); 1456 } 1457 } 1458 1459 may_encrypt = !(info->flags & IEEE80211_TX_INTFL_DONT_ENCRYPT); 1460 1461 headroom = local->tx_headroom; 1462 if (may_encrypt) 1463 headroom += IEEE80211_ENCRYPT_HEADROOM; 1464 headroom -= skb_headroom(skb); 1465 headroom = max_t(int, 0, headroom); 1466 1467 if (ieee80211_skb_resize(local, skb, headroom, may_encrypt)) { 1468 dev_kfree_skb(skb); 1469 dev_put(sdata->dev); 1470 return; 1471 } 1472 1473 info->control.vif = &sdata->vif; 1474 1475 if (ieee80211_vif_is_mesh(&sdata->vif) && 1476 ieee80211_is_data(hdr->frame_control) && 1477 !is_multicast_ether_addr(hdr->addr1)) 1478 if (mesh_nexthop_lookup(skb, sdata)) { 1479 /* skb queued: don't free */ 1480 dev_put(sdata->dev); 1481 return; 1482 } 1483 1484 ieee80211_select_queue(local, skb); 1485 ieee80211_tx(sdata, skb, false); 1486 dev_put(sdata->dev); 1487 } 1488 1489 netdev_tx_t ieee80211_monitor_start_xmit(struct sk_buff *skb, 1490 struct net_device *dev) 1491 { 1492 struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr); 1493 struct ieee80211_channel *chan = local->hw.conf.channel; 1494 struct ieee80211_radiotap_header *prthdr = 1495 (struct ieee80211_radiotap_header *)skb->data; 1496 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 1497 u16 len_rthdr; 1498 1499 /* 1500 * Frame injection is not allowed if beaconing is not allowed 1501 * or if we need radar detection. Beaconing is usually not allowed when 1502 * the mode or operation (Adhoc, AP, Mesh) does not support DFS. 1503 * Passive scan is also used in world regulatory domains where 1504 * your country is not known and as such it should be treated as 1505 * NO TX unless the channel is explicitly allowed in which case 1506 * your current regulatory domain would not have the passive scan 1507 * flag. 1508 * 1509 * Since AP mode uses monitor interfaces to inject/TX management 1510 * frames we can make AP mode the exception to this rule once it 1511 * supports radar detection as its implementation can deal with 1512 * radar detection by itself. We can do that later by adding a 1513 * monitor flag interfaces used for AP support. 1514 */ 1515 if ((chan->flags & (IEEE80211_CHAN_NO_IBSS | IEEE80211_CHAN_RADAR | 1516 IEEE80211_CHAN_PASSIVE_SCAN))) 1517 goto fail; 1518 1519 /* check for not even having the fixed radiotap header part */ 1520 if (unlikely(skb->len < sizeof(struct ieee80211_radiotap_header))) 1521 goto fail; /* too short to be possibly valid */ 1522 1523 /* is it a header version we can trust to find length from? */ 1524 if (unlikely(prthdr->it_version)) 1525 goto fail; /* only version 0 is supported */ 1526 1527 /* then there must be a radiotap header with a length we can use */ 1528 len_rthdr = ieee80211_get_radiotap_len(skb->data); 1529 1530 /* does the skb contain enough to deliver on the alleged length? */ 1531 if (unlikely(skb->len < len_rthdr)) 1532 goto fail; /* skb too short for claimed rt header extent */ 1533 1534 /* 1535 * fix up the pointers accounting for the radiotap 1536 * header still being in there. We are being given 1537 * a precooked IEEE80211 header so no need for 1538 * normal processing 1539 */ 1540 skb_set_mac_header(skb, len_rthdr); 1541 /* 1542 * these are just fixed to the end of the rt area since we 1543 * don't have any better information and at this point, nobody cares 1544 */ 1545 skb_set_network_header(skb, len_rthdr); 1546 skb_set_transport_header(skb, len_rthdr); 1547 1548 memset(info, 0, sizeof(*info)); 1549 1550 /* pass the radiotap header up to xmit */ 1551 ieee80211_xmit(IEEE80211_DEV_TO_SUB_IF(dev), skb); 1552 return NETDEV_TX_OK; 1553 1554 fail: 1555 dev_kfree_skb(skb); 1556 return NETDEV_TX_OK; /* meaning, we dealt with the skb */ 1557 } 1558 1559 /** 1560 * ieee80211_subif_start_xmit - netif start_xmit function for Ethernet-type 1561 * subinterfaces (wlan#, WDS, and VLAN interfaces) 1562 * @skb: packet to be sent 1563 * @dev: incoming interface 1564 * 1565 * Returns: 0 on success (and frees skb in this case) or 1 on failure (skb will 1566 * not be freed, and caller is responsible for either retrying later or freeing 1567 * skb). 1568 * 1569 * This function takes in an Ethernet header and encapsulates it with suitable 1570 * IEEE 802.11 header based on which interface the packet is coming in. The 1571 * encapsulated packet will then be passed to master interface, wlan#.11, for 1572 * transmission (through low-level driver). 1573 */ 1574 netdev_tx_t ieee80211_subif_start_xmit(struct sk_buff *skb, 1575 struct net_device *dev) 1576 { 1577 struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev); 1578 struct ieee80211_local *local = sdata->local; 1579 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 1580 int ret = NETDEV_TX_BUSY, head_need; 1581 u16 ethertype, hdrlen, meshhdrlen = 0; 1582 __le16 fc; 1583 struct ieee80211_hdr hdr; 1584 struct ieee80211s_hdr mesh_hdr; 1585 const u8 *encaps_data; 1586 int encaps_len, skip_header_bytes; 1587 int nh_pos, h_pos; 1588 struct sta_info *sta; 1589 u32 sta_flags = 0; 1590 1591 if (unlikely(skb->len < ETH_HLEN)) { 1592 ret = NETDEV_TX_OK; 1593 goto fail; 1594 } 1595 1596 nh_pos = skb_network_header(skb) - skb->data; 1597 h_pos = skb_transport_header(skb) - skb->data; 1598 1599 /* convert Ethernet header to proper 802.11 header (based on 1600 * operation mode) */ 1601 ethertype = (skb->data[12] << 8) | skb->data[13]; 1602 fc = cpu_to_le16(IEEE80211_FTYPE_DATA | IEEE80211_STYPE_DATA); 1603 1604 switch (sdata->vif.type) { 1605 case NL80211_IFTYPE_AP: 1606 case NL80211_IFTYPE_AP_VLAN: 1607 fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS); 1608 /* DA BSSID SA */ 1609 memcpy(hdr.addr1, skb->data, ETH_ALEN); 1610 memcpy(hdr.addr2, dev->dev_addr, ETH_ALEN); 1611 memcpy(hdr.addr3, skb->data + ETH_ALEN, ETH_ALEN); 1612 hdrlen = 24; 1613 break; 1614 case NL80211_IFTYPE_WDS: 1615 fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS); 1616 /* RA TA DA SA */ 1617 memcpy(hdr.addr1, sdata->u.wds.remote_addr, ETH_ALEN); 1618 memcpy(hdr.addr2, dev->dev_addr, ETH_ALEN); 1619 memcpy(hdr.addr3, skb->data, ETH_ALEN); 1620 memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN); 1621 hdrlen = 30; 1622 break; 1623 #ifdef CONFIG_MAC80211_MESH 1624 case NL80211_IFTYPE_MESH_POINT: 1625 if (!sdata->u.mesh.mshcfg.dot11MeshTTL) { 1626 /* Do not send frames with mesh_ttl == 0 */ 1627 sdata->u.mesh.mshstats.dropped_frames_ttl++; 1628 ret = NETDEV_TX_OK; 1629 goto fail; 1630 } 1631 1632 if (compare_ether_addr(dev->dev_addr, 1633 skb->data + ETH_ALEN) == 0) { 1634 hdrlen = ieee80211_fill_mesh_addresses(&hdr, &fc, 1635 skb->data, skb->data + ETH_ALEN); 1636 meshhdrlen = ieee80211_new_mesh_header(&mesh_hdr, 1637 sdata, NULL, NULL, NULL); 1638 } else { 1639 /* packet from other interface */ 1640 struct mesh_path *mppath; 1641 int is_mesh_mcast = 1; 1642 char *mesh_da; 1643 1644 rcu_read_lock(); 1645 if (is_multicast_ether_addr(skb->data)) 1646 /* DA TA mSA AE:SA */ 1647 mesh_da = skb->data; 1648 else { 1649 mppath = mpp_path_lookup(skb->data, sdata); 1650 if (mppath) { 1651 /* RA TA mDA mSA AE:DA SA */ 1652 mesh_da = mppath->mpp; 1653 is_mesh_mcast = 0; 1654 } else 1655 /* DA TA mSA AE:SA */ 1656 mesh_da = dev->broadcast; 1657 } 1658 hdrlen = ieee80211_fill_mesh_addresses(&hdr, &fc, 1659 mesh_da, dev->dev_addr); 1660 rcu_read_unlock(); 1661 if (is_mesh_mcast) 1662 meshhdrlen = 1663 ieee80211_new_mesh_header(&mesh_hdr, 1664 sdata, 1665 skb->data + ETH_ALEN, 1666 NULL, 1667 NULL); 1668 else 1669 meshhdrlen = 1670 ieee80211_new_mesh_header(&mesh_hdr, 1671 sdata, 1672 NULL, 1673 skb->data, 1674 skb->data + ETH_ALEN); 1675 1676 } 1677 break; 1678 #endif 1679 case NL80211_IFTYPE_STATION: 1680 fc |= cpu_to_le16(IEEE80211_FCTL_TODS); 1681 /* BSSID SA DA */ 1682 memcpy(hdr.addr1, sdata->u.mgd.bssid, ETH_ALEN); 1683 memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN); 1684 memcpy(hdr.addr3, skb->data, ETH_ALEN); 1685 hdrlen = 24; 1686 break; 1687 case NL80211_IFTYPE_ADHOC: 1688 /* DA SA BSSID */ 1689 memcpy(hdr.addr1, skb->data, ETH_ALEN); 1690 memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN); 1691 memcpy(hdr.addr3, sdata->u.ibss.bssid, ETH_ALEN); 1692 hdrlen = 24; 1693 break; 1694 default: 1695 ret = NETDEV_TX_OK; 1696 goto fail; 1697 } 1698 1699 /* 1700 * There's no need to try to look up the destination 1701 * if it is a multicast address (which can only happen 1702 * in AP mode) 1703 */ 1704 if (!is_multicast_ether_addr(hdr.addr1)) { 1705 rcu_read_lock(); 1706 sta = sta_info_get(local, hdr.addr1); 1707 if (sta) 1708 sta_flags = get_sta_flags(sta); 1709 rcu_read_unlock(); 1710 } 1711 1712 /* receiver and we are QoS enabled, use a QoS type frame */ 1713 if ((sta_flags & WLAN_STA_WME) && local->hw.queues >= 4) { 1714 fc |= cpu_to_le16(IEEE80211_STYPE_QOS_DATA); 1715 hdrlen += 2; 1716 } 1717 1718 /* 1719 * Drop unicast frames to unauthorised stations unless they are 1720 * EAPOL frames from the local station. 1721 */ 1722 if (!ieee80211_vif_is_mesh(&sdata->vif) && 1723 unlikely(!is_multicast_ether_addr(hdr.addr1) && 1724 !(sta_flags & WLAN_STA_AUTHORIZED) && 1725 !(ethertype == ETH_P_PAE && 1726 compare_ether_addr(dev->dev_addr, 1727 skb->data + ETH_ALEN) == 0))) { 1728 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG 1729 if (net_ratelimit()) 1730 printk(KERN_DEBUG "%s: dropped frame to %pM" 1731 " (unauthorized port)\n", dev->name, 1732 hdr.addr1); 1733 #endif 1734 1735 I802_DEBUG_INC(local->tx_handlers_drop_unauth_port); 1736 1737 ret = NETDEV_TX_OK; 1738 goto fail; 1739 } 1740 1741 hdr.frame_control = fc; 1742 hdr.duration_id = 0; 1743 hdr.seq_ctrl = 0; 1744 1745 skip_header_bytes = ETH_HLEN; 1746 if (ethertype == ETH_P_AARP || ethertype == ETH_P_IPX) { 1747 encaps_data = bridge_tunnel_header; 1748 encaps_len = sizeof(bridge_tunnel_header); 1749 skip_header_bytes -= 2; 1750 } else if (ethertype >= 0x600) { 1751 encaps_data = rfc1042_header; 1752 encaps_len = sizeof(rfc1042_header); 1753 skip_header_bytes -= 2; 1754 } else { 1755 encaps_data = NULL; 1756 encaps_len = 0; 1757 } 1758 1759 skb_pull(skb, skip_header_bytes); 1760 nh_pos -= skip_header_bytes; 1761 h_pos -= skip_header_bytes; 1762 1763 head_need = hdrlen + encaps_len + meshhdrlen - skb_headroom(skb); 1764 1765 /* 1766 * So we need to modify the skb header and hence need a copy of 1767 * that. The head_need variable above doesn't, so far, include 1768 * the needed header space that we don't need right away. If we 1769 * can, then we don't reallocate right now but only after the 1770 * frame arrives at the master device (if it does...) 1771 * 1772 * If we cannot, however, then we will reallocate to include all 1773 * the ever needed space. Also, if we need to reallocate it anyway, 1774 * make it big enough for everything we may ever need. 1775 */ 1776 1777 if (head_need > 0 || skb_cloned(skb)) { 1778 head_need += IEEE80211_ENCRYPT_HEADROOM; 1779 head_need += local->tx_headroom; 1780 head_need = max_t(int, 0, head_need); 1781 if (ieee80211_skb_resize(local, skb, head_need, true)) 1782 goto fail; 1783 } 1784 1785 if (encaps_data) { 1786 memcpy(skb_push(skb, encaps_len), encaps_data, encaps_len); 1787 nh_pos += encaps_len; 1788 h_pos += encaps_len; 1789 } 1790 1791 if (meshhdrlen > 0) { 1792 memcpy(skb_push(skb, meshhdrlen), &mesh_hdr, meshhdrlen); 1793 nh_pos += meshhdrlen; 1794 h_pos += meshhdrlen; 1795 } 1796 1797 if (ieee80211_is_data_qos(fc)) { 1798 __le16 *qos_control; 1799 1800 qos_control = (__le16*) skb_push(skb, 2); 1801 memcpy(skb_push(skb, hdrlen - 2), &hdr, hdrlen - 2); 1802 /* 1803 * Maybe we could actually set some fields here, for now just 1804 * initialise to zero to indicate no special operation. 1805 */ 1806 *qos_control = 0; 1807 } else 1808 memcpy(skb_push(skb, hdrlen), &hdr, hdrlen); 1809 1810 nh_pos += hdrlen; 1811 h_pos += hdrlen; 1812 1813 dev->stats.tx_packets++; 1814 dev->stats.tx_bytes += skb->len; 1815 1816 /* Update skb pointers to various headers since this modified frame 1817 * is going to go through Linux networking code that may potentially 1818 * need things like pointer to IP header. */ 1819 skb_set_mac_header(skb, 0); 1820 skb_set_network_header(skb, nh_pos); 1821 skb_set_transport_header(skb, h_pos); 1822 1823 memset(info, 0, sizeof(*info)); 1824 1825 dev->trans_start = jiffies; 1826 ieee80211_xmit(sdata, skb); 1827 1828 return NETDEV_TX_OK; 1829 1830 fail: 1831 if (ret == NETDEV_TX_OK) 1832 dev_kfree_skb(skb); 1833 1834 return ret; 1835 } 1836 1837 1838 /* 1839 * ieee80211_clear_tx_pending may not be called in a context where 1840 * it is possible that it packets could come in again. 1841 */ 1842 void ieee80211_clear_tx_pending(struct ieee80211_local *local) 1843 { 1844 int i; 1845 1846 for (i = 0; i < local->hw.queues; i++) 1847 skb_queue_purge(&local->pending[i]); 1848 } 1849 1850 static bool ieee80211_tx_pending_skb(struct ieee80211_local *local, 1851 struct sk_buff *skb) 1852 { 1853 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 1854 struct ieee80211_sub_if_data *sdata; 1855 struct sta_info *sta; 1856 struct ieee80211_hdr *hdr; 1857 int ret; 1858 bool result = true; 1859 1860 sdata = vif_to_sdata(info->control.vif); 1861 1862 if (info->flags & IEEE80211_TX_INTFL_NEED_TXPROCESSING) { 1863 ieee80211_tx(sdata, skb, true); 1864 } else { 1865 hdr = (struct ieee80211_hdr *)skb->data; 1866 sta = sta_info_get(local, hdr->addr1); 1867 1868 ret = __ieee80211_tx(local, &skb, sta, true); 1869 if (ret != IEEE80211_TX_OK) 1870 result = false; 1871 } 1872 1873 return result; 1874 } 1875 1876 /* 1877 * Transmit all pending packets. Called from tasklet. 1878 */ 1879 void ieee80211_tx_pending(unsigned long data) 1880 { 1881 struct ieee80211_local *local = (struct ieee80211_local *)data; 1882 unsigned long flags; 1883 int i; 1884 bool txok; 1885 1886 rcu_read_lock(); 1887 1888 spin_lock_irqsave(&local->queue_stop_reason_lock, flags); 1889 for (i = 0; i < local->hw.queues; i++) { 1890 /* 1891 * If queue is stopped by something other than due to pending 1892 * frames, or we have no pending frames, proceed to next queue. 1893 */ 1894 if (local->queue_stop_reasons[i] || 1895 skb_queue_empty(&local->pending[i])) 1896 continue; 1897 1898 while (!skb_queue_empty(&local->pending[i])) { 1899 struct sk_buff *skb = __skb_dequeue(&local->pending[i]); 1900 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 1901 struct ieee80211_sub_if_data *sdata; 1902 1903 if (WARN_ON(!info->control.vif)) { 1904 kfree_skb(skb); 1905 continue; 1906 } 1907 1908 sdata = vif_to_sdata(info->control.vif); 1909 dev_hold(sdata->dev); 1910 spin_unlock_irqrestore(&local->queue_stop_reason_lock, 1911 flags); 1912 1913 txok = ieee80211_tx_pending_skb(local, skb); 1914 dev_put(sdata->dev); 1915 if (!txok) 1916 __skb_queue_head(&local->pending[i], skb); 1917 spin_lock_irqsave(&local->queue_stop_reason_lock, 1918 flags); 1919 if (!txok) 1920 break; 1921 } 1922 } 1923 spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags); 1924 1925 rcu_read_unlock(); 1926 } 1927 1928 /* functions for drivers to get certain frames */ 1929 1930 static void ieee80211_beacon_add_tim(struct ieee80211_if_ap *bss, 1931 struct sk_buff *skb, 1932 struct beacon_data *beacon) 1933 { 1934 u8 *pos, *tim; 1935 int aid0 = 0; 1936 int i, have_bits = 0, n1, n2; 1937 1938 /* Generate bitmap for TIM only if there are any STAs in power save 1939 * mode. */ 1940 if (atomic_read(&bss->num_sta_ps) > 0) 1941 /* in the hope that this is faster than 1942 * checking byte-for-byte */ 1943 have_bits = !bitmap_empty((unsigned long*)bss->tim, 1944 IEEE80211_MAX_AID+1); 1945 1946 if (bss->dtim_count == 0) 1947 bss->dtim_count = beacon->dtim_period - 1; 1948 else 1949 bss->dtim_count--; 1950 1951 tim = pos = (u8 *) skb_put(skb, 6); 1952 *pos++ = WLAN_EID_TIM; 1953 *pos++ = 4; 1954 *pos++ = bss->dtim_count; 1955 *pos++ = beacon->dtim_period; 1956 1957 if (bss->dtim_count == 0 && !skb_queue_empty(&bss->ps_bc_buf)) 1958 aid0 = 1; 1959 1960 if (have_bits) { 1961 /* Find largest even number N1 so that bits numbered 1 through 1962 * (N1 x 8) - 1 in the bitmap are 0 and number N2 so that bits 1963 * (N2 + 1) x 8 through 2007 are 0. */ 1964 n1 = 0; 1965 for (i = 0; i < IEEE80211_MAX_TIM_LEN; i++) { 1966 if (bss->tim[i]) { 1967 n1 = i & 0xfe; 1968 break; 1969 } 1970 } 1971 n2 = n1; 1972 for (i = IEEE80211_MAX_TIM_LEN - 1; i >= n1; i--) { 1973 if (bss->tim[i]) { 1974 n2 = i; 1975 break; 1976 } 1977 } 1978 1979 /* Bitmap control */ 1980 *pos++ = n1 | aid0; 1981 /* Part Virt Bitmap */ 1982 memcpy(pos, bss->tim + n1, n2 - n1 + 1); 1983 1984 tim[1] = n2 - n1 + 4; 1985 skb_put(skb, n2 - n1); 1986 } else { 1987 *pos++ = aid0; /* Bitmap control */ 1988 *pos++ = 0; /* Part Virt Bitmap */ 1989 } 1990 } 1991 1992 struct sk_buff *ieee80211_beacon_get(struct ieee80211_hw *hw, 1993 struct ieee80211_vif *vif) 1994 { 1995 struct ieee80211_local *local = hw_to_local(hw); 1996 struct sk_buff *skb = NULL; 1997 struct ieee80211_tx_info *info; 1998 struct ieee80211_sub_if_data *sdata = NULL; 1999 struct ieee80211_if_ap *ap = NULL; 2000 struct beacon_data *beacon; 2001 struct ieee80211_supported_band *sband; 2002 enum ieee80211_band band = local->hw.conf.channel->band; 2003 2004 sband = local->hw.wiphy->bands[band]; 2005 2006 rcu_read_lock(); 2007 2008 sdata = vif_to_sdata(vif); 2009 2010 if (sdata->vif.type == NL80211_IFTYPE_AP) { 2011 ap = &sdata->u.ap; 2012 beacon = rcu_dereference(ap->beacon); 2013 if (ap && beacon) { 2014 /* 2015 * headroom, head length, 2016 * tail length and maximum TIM length 2017 */ 2018 skb = dev_alloc_skb(local->tx_headroom + 2019 beacon->head_len + 2020 beacon->tail_len + 256); 2021 if (!skb) 2022 goto out; 2023 2024 skb_reserve(skb, local->tx_headroom); 2025 memcpy(skb_put(skb, beacon->head_len), beacon->head, 2026 beacon->head_len); 2027 2028 /* 2029 * Not very nice, but we want to allow the driver to call 2030 * ieee80211_beacon_get() as a response to the set_tim() 2031 * callback. That, however, is already invoked under the 2032 * sta_lock to guarantee consistent and race-free update 2033 * of the tim bitmap in mac80211 and the driver. 2034 */ 2035 if (local->tim_in_locked_section) { 2036 ieee80211_beacon_add_tim(ap, skb, beacon); 2037 } else { 2038 unsigned long flags; 2039 2040 spin_lock_irqsave(&local->sta_lock, flags); 2041 ieee80211_beacon_add_tim(ap, skb, beacon); 2042 spin_unlock_irqrestore(&local->sta_lock, flags); 2043 } 2044 2045 if (beacon->tail) 2046 memcpy(skb_put(skb, beacon->tail_len), 2047 beacon->tail, beacon->tail_len); 2048 } else 2049 goto out; 2050 } else if (sdata->vif.type == NL80211_IFTYPE_ADHOC) { 2051 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 2052 struct ieee80211_hdr *hdr; 2053 struct sk_buff *presp = rcu_dereference(ifibss->presp); 2054 2055 if (!presp) 2056 goto out; 2057 2058 skb = skb_copy(presp, GFP_ATOMIC); 2059 if (!skb) 2060 goto out; 2061 2062 hdr = (struct ieee80211_hdr *) skb->data; 2063 hdr->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 2064 IEEE80211_STYPE_BEACON); 2065 } else if (ieee80211_vif_is_mesh(&sdata->vif)) { 2066 struct ieee80211_mgmt *mgmt; 2067 u8 *pos; 2068 2069 /* headroom, head length, tail length and maximum TIM length */ 2070 skb = dev_alloc_skb(local->tx_headroom + 400); 2071 if (!skb) 2072 goto out; 2073 2074 skb_reserve(skb, local->hw.extra_tx_headroom); 2075 mgmt = (struct ieee80211_mgmt *) 2076 skb_put(skb, 24 + sizeof(mgmt->u.beacon)); 2077 memset(mgmt, 0, 24 + sizeof(mgmt->u.beacon)); 2078 mgmt->frame_control = 2079 cpu_to_le16(IEEE80211_FTYPE_MGMT | IEEE80211_STYPE_BEACON); 2080 memset(mgmt->da, 0xff, ETH_ALEN); 2081 memcpy(mgmt->sa, sdata->dev->dev_addr, ETH_ALEN); 2082 /* BSSID is left zeroed, wildcard value */ 2083 mgmt->u.beacon.beacon_int = 2084 cpu_to_le16(sdata->vif.bss_conf.beacon_int); 2085 mgmt->u.beacon.capab_info = 0x0; /* 0x0 for MPs */ 2086 2087 pos = skb_put(skb, 2); 2088 *pos++ = WLAN_EID_SSID; 2089 *pos++ = 0x0; 2090 2091 mesh_mgmt_ies_add(skb, sdata); 2092 } else { 2093 WARN_ON(1); 2094 goto out; 2095 } 2096 2097 info = IEEE80211_SKB_CB(skb); 2098 2099 info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT; 2100 info->band = band; 2101 /* 2102 * XXX: For now, always use the lowest rate 2103 */ 2104 info->control.rates[0].idx = 0; 2105 info->control.rates[0].count = 1; 2106 info->control.rates[1].idx = -1; 2107 info->control.rates[2].idx = -1; 2108 info->control.rates[3].idx = -1; 2109 info->control.rates[4].idx = -1; 2110 BUILD_BUG_ON(IEEE80211_TX_MAX_RATES != 5); 2111 2112 info->control.vif = vif; 2113 2114 info->flags |= IEEE80211_TX_CTL_NO_ACK; 2115 info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT; 2116 info->flags |= IEEE80211_TX_CTL_ASSIGN_SEQ; 2117 out: 2118 rcu_read_unlock(); 2119 return skb; 2120 } 2121 EXPORT_SYMBOL(ieee80211_beacon_get); 2122 2123 void ieee80211_rts_get(struct ieee80211_hw *hw, struct ieee80211_vif *vif, 2124 const void *frame, size_t frame_len, 2125 const struct ieee80211_tx_info *frame_txctl, 2126 struct ieee80211_rts *rts) 2127 { 2128 const struct ieee80211_hdr *hdr = frame; 2129 2130 rts->frame_control = 2131 cpu_to_le16(IEEE80211_FTYPE_CTL | IEEE80211_STYPE_RTS); 2132 rts->duration = ieee80211_rts_duration(hw, vif, frame_len, 2133 frame_txctl); 2134 memcpy(rts->ra, hdr->addr1, sizeof(rts->ra)); 2135 memcpy(rts->ta, hdr->addr2, sizeof(rts->ta)); 2136 } 2137 EXPORT_SYMBOL(ieee80211_rts_get); 2138 2139 void ieee80211_ctstoself_get(struct ieee80211_hw *hw, struct ieee80211_vif *vif, 2140 const void *frame, size_t frame_len, 2141 const struct ieee80211_tx_info *frame_txctl, 2142 struct ieee80211_cts *cts) 2143 { 2144 const struct ieee80211_hdr *hdr = frame; 2145 2146 cts->frame_control = 2147 cpu_to_le16(IEEE80211_FTYPE_CTL | IEEE80211_STYPE_CTS); 2148 cts->duration = ieee80211_ctstoself_duration(hw, vif, 2149 frame_len, frame_txctl); 2150 memcpy(cts->ra, hdr->addr1, sizeof(cts->ra)); 2151 } 2152 EXPORT_SYMBOL(ieee80211_ctstoself_get); 2153 2154 struct sk_buff * 2155 ieee80211_get_buffered_bc(struct ieee80211_hw *hw, 2156 struct ieee80211_vif *vif) 2157 { 2158 struct ieee80211_local *local = hw_to_local(hw); 2159 struct sk_buff *skb = NULL; 2160 struct sta_info *sta; 2161 struct ieee80211_tx_data tx; 2162 struct ieee80211_sub_if_data *sdata; 2163 struct ieee80211_if_ap *bss = NULL; 2164 struct beacon_data *beacon; 2165 struct ieee80211_tx_info *info; 2166 2167 sdata = vif_to_sdata(vif); 2168 bss = &sdata->u.ap; 2169 2170 rcu_read_lock(); 2171 beacon = rcu_dereference(bss->beacon); 2172 2173 if (sdata->vif.type != NL80211_IFTYPE_AP || !beacon || !beacon->head) 2174 goto out; 2175 2176 if (bss->dtim_count != 0) 2177 goto out; /* send buffered bc/mc only after DTIM beacon */ 2178 2179 while (1) { 2180 skb = skb_dequeue(&bss->ps_bc_buf); 2181 if (!skb) 2182 goto out; 2183 local->total_ps_buffered--; 2184 2185 if (!skb_queue_empty(&bss->ps_bc_buf) && skb->len >= 2) { 2186 struct ieee80211_hdr *hdr = 2187 (struct ieee80211_hdr *) skb->data; 2188 /* more buffered multicast/broadcast frames ==> set 2189 * MoreData flag in IEEE 802.11 header to inform PS 2190 * STAs */ 2191 hdr->frame_control |= 2192 cpu_to_le16(IEEE80211_FCTL_MOREDATA); 2193 } 2194 2195 if (!ieee80211_tx_prepare(sdata, &tx, skb)) 2196 break; 2197 dev_kfree_skb_any(skb); 2198 } 2199 2200 info = IEEE80211_SKB_CB(skb); 2201 2202 sta = tx.sta; 2203 tx.flags |= IEEE80211_TX_PS_BUFFERED; 2204 tx.channel = local->hw.conf.channel; 2205 info->band = tx.channel->band; 2206 2207 if (invoke_tx_handlers(&tx)) 2208 skb = NULL; 2209 out: 2210 rcu_read_unlock(); 2211 2212 return skb; 2213 } 2214 EXPORT_SYMBOL(ieee80211_get_buffered_bc); 2215 2216 void ieee80211_tx_skb(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb, 2217 int encrypt) 2218 { 2219 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 2220 skb_set_mac_header(skb, 0); 2221 skb_set_network_header(skb, 0); 2222 skb_set_transport_header(skb, 0); 2223 2224 if (!encrypt) 2225 info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT; 2226 2227 /* 2228 * The other path calling ieee80211_xmit is from the tasklet, 2229 * and while we can handle concurrent transmissions locking 2230 * requirements are that we do not come into tx with bhs on. 2231 */ 2232 local_bh_disable(); 2233 ieee80211_xmit(sdata, skb); 2234 local_bh_enable(); 2235 } 2236