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 info->flags |= IEEE80211_TX_CTL_SEND_AFTER_DTIM; 321 322 /* device releases frame after DTIM beacon */ 323 if (!(tx->local->hw.flags & IEEE80211_HW_HOST_BROADCAST_PS_BUFFERING)) 324 return TX_CONTINUE; 325 326 /* buffered in mac80211 */ 327 if (tx->local->total_ps_buffered >= TOTAL_MAX_TX_BUFFER) 328 purge_old_ps_buffers(tx->local); 329 330 if (skb_queue_len(&tx->sdata->bss->ps_bc_buf) >= AP_MAX_BC_BUFFER) { 331 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 332 if (net_ratelimit()) 333 printk(KERN_DEBUG "%s: BC TX buffer full - dropping the oldest frame\n", 334 tx->dev->name); 335 #endif 336 dev_kfree_skb(skb_dequeue(&tx->sdata->bss->ps_bc_buf)); 337 } else 338 tx->local->total_ps_buffered++; 339 340 skb_queue_tail(&tx->sdata->bss->ps_bc_buf, tx->skb); 341 342 return TX_QUEUED; 343 } 344 345 static int ieee80211_use_mfp(__le16 fc, struct sta_info *sta, 346 struct sk_buff *skb) 347 { 348 if (!ieee80211_is_mgmt(fc)) 349 return 0; 350 351 if (sta == NULL || !test_sta_flags(sta, WLAN_STA_MFP)) 352 return 0; 353 354 if (!ieee80211_is_robust_mgmt_frame((struct ieee80211_hdr *) 355 skb->data)) 356 return 0; 357 358 return 1; 359 } 360 361 static ieee80211_tx_result 362 ieee80211_tx_h_unicast_ps_buf(struct ieee80211_tx_data *tx) 363 { 364 struct sta_info *sta = tx->sta; 365 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb); 366 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data; 367 u32 staflags; 368 369 if (unlikely(!sta || 370 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_STA | WLAN_STA_PS_DRIVER)) && 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 /* 402 * Queue frame to be sent after STA wakes up/polls, 403 * but don't set the TIM bit if the driver is blocking 404 * wakeup or poll response transmissions anyway. 405 */ 406 if (skb_queue_empty(&sta->ps_tx_buf) && 407 !(staflags & WLAN_STA_PS_DRIVER)) 408 sta_info_set_tim_bit(sta); 409 410 info->control.jiffies = jiffies; 411 info->control.vif = &tx->sdata->vif; 412 info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING; 413 skb_queue_tail(&sta->ps_tx_buf, tx->skb); 414 return TX_QUEUED; 415 } 416 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 417 else if (unlikely(staflags & WLAN_STA_PS_STA)) { 418 printk(KERN_DEBUG "%s: STA %pM in PS mode, but pspoll " 419 "set -> send frame\n", tx->dev->name, 420 sta->sta.addr); 421 } 422 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 423 424 return TX_CONTINUE; 425 } 426 427 static ieee80211_tx_result debug_noinline 428 ieee80211_tx_h_ps_buf(struct ieee80211_tx_data *tx) 429 { 430 if (unlikely(tx->flags & IEEE80211_TX_PS_BUFFERED)) 431 return TX_CONTINUE; 432 433 if (tx->flags & IEEE80211_TX_UNICAST) 434 return ieee80211_tx_h_unicast_ps_buf(tx); 435 else 436 return ieee80211_tx_h_multicast_ps_buf(tx); 437 } 438 439 static ieee80211_tx_result debug_noinline 440 ieee80211_tx_h_select_key(struct ieee80211_tx_data *tx) 441 { 442 struct ieee80211_key *key = NULL; 443 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb); 444 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data; 445 446 if (unlikely(info->flags & IEEE80211_TX_INTFL_DONT_ENCRYPT)) 447 tx->key = NULL; 448 else if (tx->sta && (key = rcu_dereference(tx->sta->key))) 449 tx->key = key; 450 else if (ieee80211_is_mgmt(hdr->frame_control) && 451 (key = rcu_dereference(tx->sdata->default_mgmt_key))) 452 tx->key = key; 453 else if ((key = rcu_dereference(tx->sdata->default_key))) 454 tx->key = key; 455 else if (tx->sdata->drop_unencrypted && 456 (tx->skb->protocol != cpu_to_be16(ETH_P_PAE)) && 457 !(info->flags & IEEE80211_TX_CTL_INJECTED) && 458 (!ieee80211_is_robust_mgmt_frame(hdr) || 459 (ieee80211_is_action(hdr->frame_control) && 460 tx->sta && test_sta_flags(tx->sta, WLAN_STA_MFP)))) { 461 I802_DEBUG_INC(tx->local->tx_handlers_drop_unencrypted); 462 return TX_DROP; 463 } else 464 tx->key = NULL; 465 466 if (tx->key) { 467 tx->key->tx_rx_count++; 468 /* TODO: add threshold stuff again */ 469 470 switch (tx->key->conf.alg) { 471 case ALG_WEP: 472 if (ieee80211_is_auth(hdr->frame_control)) 473 break; 474 case ALG_TKIP: 475 if (!ieee80211_is_data_present(hdr->frame_control)) 476 tx->key = NULL; 477 break; 478 case ALG_CCMP: 479 if (!ieee80211_is_data_present(hdr->frame_control) && 480 !ieee80211_use_mfp(hdr->frame_control, tx->sta, 481 tx->skb)) 482 tx->key = NULL; 483 break; 484 case ALG_AES_CMAC: 485 if (!ieee80211_is_mgmt(hdr->frame_control)) 486 tx->key = NULL; 487 break; 488 } 489 } 490 491 if (!tx->key || !(tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE)) 492 info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT; 493 494 return TX_CONTINUE; 495 } 496 497 static ieee80211_tx_result debug_noinline 498 ieee80211_tx_h_rate_ctrl(struct ieee80211_tx_data *tx) 499 { 500 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb); 501 struct ieee80211_hdr *hdr = (void *)tx->skb->data; 502 struct ieee80211_supported_band *sband; 503 struct ieee80211_rate *rate; 504 int i, len; 505 bool inval = false, rts = false, short_preamble = false; 506 struct ieee80211_tx_rate_control txrc; 507 u32 sta_flags; 508 509 memset(&txrc, 0, sizeof(txrc)); 510 511 sband = tx->local->hw.wiphy->bands[tx->channel->band]; 512 513 len = min_t(int, tx->skb->len + FCS_LEN, 514 tx->local->hw.wiphy->frag_threshold); 515 516 /* set up the tx rate control struct we give the RC algo */ 517 txrc.hw = local_to_hw(tx->local); 518 txrc.sband = sband; 519 txrc.bss_conf = &tx->sdata->vif.bss_conf; 520 txrc.skb = tx->skb; 521 txrc.reported_rate.idx = -1; 522 txrc.max_rate_idx = tx->sdata->max_ratectrl_rateidx; 523 524 /* set up RTS protection if desired */ 525 if (len > tx->local->hw.wiphy->rts_threshold) { 526 txrc.rts = rts = true; 527 } 528 529 /* 530 * Use short preamble if the BSS can handle it, but not for 531 * management frames unless we know the receiver can handle 532 * that -- the management frame might be to a station that 533 * just wants a probe response. 534 */ 535 if (tx->sdata->vif.bss_conf.use_short_preamble && 536 (ieee80211_is_data(hdr->frame_control) || 537 (tx->sta && test_sta_flags(tx->sta, WLAN_STA_SHORT_PREAMBLE)))) 538 txrc.short_preamble = short_preamble = true; 539 540 sta_flags = tx->sta ? get_sta_flags(tx->sta) : 0; 541 542 /* 543 * Lets not bother rate control if we're associated and cannot 544 * talk to the sta. This should not happen. 545 */ 546 if (WARN(test_bit(SCAN_SW_SCANNING, &tx->local->scanning) && 547 (sta_flags & WLAN_STA_ASSOC) && 548 !rate_usable_index_exists(sband, &tx->sta->sta), 549 "%s: Dropped data frame as no usable bitrate found while " 550 "scanning and associated. Target station: " 551 "%pM on %d GHz band\n", 552 tx->dev->name, hdr->addr1, 553 tx->channel->band ? 5 : 2)) 554 return TX_DROP; 555 556 /* 557 * If we're associated with the sta at this point we know we can at 558 * least send the frame at the lowest bit rate. 559 */ 560 rate_control_get_rate(tx->sdata, tx->sta, &txrc); 561 562 if (unlikely(info->control.rates[0].idx < 0)) 563 return TX_DROP; 564 565 if (txrc.reported_rate.idx < 0) 566 txrc.reported_rate = info->control.rates[0]; 567 568 if (tx->sta) 569 tx->sta->last_tx_rate = txrc.reported_rate; 570 571 if (unlikely(!info->control.rates[0].count)) 572 info->control.rates[0].count = 1; 573 574 if (WARN_ON_ONCE((info->control.rates[0].count > 1) && 575 (info->flags & IEEE80211_TX_CTL_NO_ACK))) 576 info->control.rates[0].count = 1; 577 578 if (is_multicast_ether_addr(hdr->addr1)) { 579 /* 580 * XXX: verify the rate is in the basic rateset 581 */ 582 return TX_CONTINUE; 583 } 584 585 /* 586 * set up the RTS/CTS rate as the fastest basic rate 587 * that is not faster than the data rate 588 * 589 * XXX: Should this check all retry rates? 590 */ 591 if (!(info->control.rates[0].flags & IEEE80211_TX_RC_MCS)) { 592 s8 baserate = 0; 593 594 rate = &sband->bitrates[info->control.rates[0].idx]; 595 596 for (i = 0; i < sband->n_bitrates; i++) { 597 /* must be a basic rate */ 598 if (!(tx->sdata->vif.bss_conf.basic_rates & BIT(i))) 599 continue; 600 /* must not be faster than the data rate */ 601 if (sband->bitrates[i].bitrate > rate->bitrate) 602 continue; 603 /* maximum */ 604 if (sband->bitrates[baserate].bitrate < 605 sband->bitrates[i].bitrate) 606 baserate = i; 607 } 608 609 info->control.rts_cts_rate_idx = baserate; 610 } 611 612 for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) { 613 /* 614 * make sure there's no valid rate following 615 * an invalid one, just in case drivers don't 616 * take the API seriously to stop at -1. 617 */ 618 if (inval) { 619 info->control.rates[i].idx = -1; 620 continue; 621 } 622 if (info->control.rates[i].idx < 0) { 623 inval = true; 624 continue; 625 } 626 627 /* 628 * For now assume MCS is already set up correctly, this 629 * needs to be fixed. 630 */ 631 if (info->control.rates[i].flags & IEEE80211_TX_RC_MCS) { 632 WARN_ON(info->control.rates[i].idx > 76); 633 continue; 634 } 635 636 /* set up RTS protection if desired */ 637 if (rts) 638 info->control.rates[i].flags |= 639 IEEE80211_TX_RC_USE_RTS_CTS; 640 641 /* RC is busted */ 642 if (WARN_ON_ONCE(info->control.rates[i].idx >= 643 sband->n_bitrates)) { 644 info->control.rates[i].idx = -1; 645 continue; 646 } 647 648 rate = &sband->bitrates[info->control.rates[i].idx]; 649 650 /* set up short preamble */ 651 if (short_preamble && 652 rate->flags & IEEE80211_RATE_SHORT_PREAMBLE) 653 info->control.rates[i].flags |= 654 IEEE80211_TX_RC_USE_SHORT_PREAMBLE; 655 656 /* set up G protection */ 657 if (!rts && tx->sdata->vif.bss_conf.use_cts_prot && 658 rate->flags & IEEE80211_RATE_ERP_G) 659 info->control.rates[i].flags |= 660 IEEE80211_TX_RC_USE_CTS_PROTECT; 661 } 662 663 return TX_CONTINUE; 664 } 665 666 static ieee80211_tx_result debug_noinline 667 ieee80211_tx_h_misc(struct ieee80211_tx_data *tx) 668 { 669 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb); 670 671 if (tx->sta) 672 info->control.sta = &tx->sta->sta; 673 674 return TX_CONTINUE; 675 } 676 677 static ieee80211_tx_result debug_noinline 678 ieee80211_tx_h_sequence(struct ieee80211_tx_data *tx) 679 { 680 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb); 681 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data; 682 u16 *seq; 683 u8 *qc; 684 int tid; 685 686 /* 687 * Packet injection may want to control the sequence 688 * number, if we have no matching interface then we 689 * neither assign one ourselves nor ask the driver to. 690 */ 691 if (unlikely(info->control.vif->type == NL80211_IFTYPE_MONITOR)) 692 return TX_CONTINUE; 693 694 if (unlikely(ieee80211_is_ctl(hdr->frame_control))) 695 return TX_CONTINUE; 696 697 if (ieee80211_hdrlen(hdr->frame_control) < 24) 698 return TX_CONTINUE; 699 700 /* 701 * Anything but QoS data that has a sequence number field 702 * (is long enough) gets a sequence number from the global 703 * counter. 704 */ 705 if (!ieee80211_is_data_qos(hdr->frame_control)) { 706 /* driver should assign sequence number */ 707 info->flags |= IEEE80211_TX_CTL_ASSIGN_SEQ; 708 /* for pure STA mode without beacons, we can do it */ 709 hdr->seq_ctrl = cpu_to_le16(tx->sdata->sequence_number); 710 tx->sdata->sequence_number += 0x10; 711 return TX_CONTINUE; 712 } 713 714 /* 715 * This should be true for injected/management frames only, for 716 * management frames we have set the IEEE80211_TX_CTL_ASSIGN_SEQ 717 * above since they are not QoS-data frames. 718 */ 719 if (!tx->sta) 720 return TX_CONTINUE; 721 722 /* include per-STA, per-TID sequence counter */ 723 724 qc = ieee80211_get_qos_ctl(hdr); 725 tid = *qc & IEEE80211_QOS_CTL_TID_MASK; 726 seq = &tx->sta->tid_seq[tid]; 727 728 hdr->seq_ctrl = cpu_to_le16(*seq); 729 730 /* Increase the sequence number. */ 731 *seq = (*seq + 0x10) & IEEE80211_SCTL_SEQ; 732 733 return TX_CONTINUE; 734 } 735 736 static int ieee80211_fragment(struct ieee80211_local *local, 737 struct sk_buff *skb, int hdrlen, 738 int frag_threshold) 739 { 740 struct sk_buff *tail = skb, *tmp; 741 int per_fragm = frag_threshold - hdrlen - FCS_LEN; 742 int pos = hdrlen + per_fragm; 743 int rem = skb->len - hdrlen - per_fragm; 744 745 if (WARN_ON(rem < 0)) 746 return -EINVAL; 747 748 while (rem) { 749 int fraglen = per_fragm; 750 751 if (fraglen > rem) 752 fraglen = rem; 753 rem -= fraglen; 754 tmp = dev_alloc_skb(local->tx_headroom + 755 frag_threshold + 756 IEEE80211_ENCRYPT_HEADROOM + 757 IEEE80211_ENCRYPT_TAILROOM); 758 if (!tmp) 759 return -ENOMEM; 760 tail->next = tmp; 761 tail = tmp; 762 skb_reserve(tmp, local->tx_headroom + 763 IEEE80211_ENCRYPT_HEADROOM); 764 /* copy control information */ 765 memcpy(tmp->cb, skb->cb, sizeof(tmp->cb)); 766 skb_copy_queue_mapping(tmp, skb); 767 tmp->priority = skb->priority; 768 tmp->dev = skb->dev; 769 770 /* copy header and data */ 771 memcpy(skb_put(tmp, hdrlen), skb->data, hdrlen); 772 memcpy(skb_put(tmp, fraglen), skb->data + pos, fraglen); 773 774 pos += fraglen; 775 } 776 777 skb->len = hdrlen + per_fragm; 778 return 0; 779 } 780 781 static ieee80211_tx_result debug_noinline 782 ieee80211_tx_h_fragment(struct ieee80211_tx_data *tx) 783 { 784 struct sk_buff *skb = tx->skb; 785 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 786 struct ieee80211_hdr *hdr = (void *)skb->data; 787 int frag_threshold = tx->local->hw.wiphy->frag_threshold; 788 int hdrlen; 789 int fragnum; 790 791 if (!(tx->flags & IEEE80211_TX_FRAGMENTED)) 792 return TX_CONTINUE; 793 794 /* 795 * Warn when submitting a fragmented A-MPDU frame and drop it. 796 * This scenario is handled in ieee80211_tx_prepare but extra 797 * caution taken here as fragmented ampdu may cause Tx stop. 798 */ 799 if (WARN_ON(info->flags & IEEE80211_TX_CTL_AMPDU)) 800 return TX_DROP; 801 802 hdrlen = ieee80211_hdrlen(hdr->frame_control); 803 804 /* internal error, why is TX_FRAGMENTED set? */ 805 if (WARN_ON(skb->len + FCS_LEN <= frag_threshold)) 806 return TX_DROP; 807 808 /* 809 * Now fragment the frame. This will allocate all the fragments and 810 * chain them (using skb as the first fragment) to skb->next. 811 * During transmission, we will remove the successfully transmitted 812 * fragments from this list. When the low-level driver rejects one 813 * of the fragments then we will simply pretend to accept the skb 814 * but store it away as pending. 815 */ 816 if (ieee80211_fragment(tx->local, skb, hdrlen, frag_threshold)) 817 return TX_DROP; 818 819 /* update duration/seq/flags of fragments */ 820 fragnum = 0; 821 do { 822 int next_len; 823 const __le16 morefrags = cpu_to_le16(IEEE80211_FCTL_MOREFRAGS); 824 825 hdr = (void *)skb->data; 826 info = IEEE80211_SKB_CB(skb); 827 828 if (skb->next) { 829 hdr->frame_control |= morefrags; 830 next_len = skb->next->len; 831 /* 832 * No multi-rate retries for fragmented frames, that 833 * would completely throw off the NAV at other STAs. 834 */ 835 info->control.rates[1].idx = -1; 836 info->control.rates[2].idx = -1; 837 info->control.rates[3].idx = -1; 838 info->control.rates[4].idx = -1; 839 BUILD_BUG_ON(IEEE80211_TX_MAX_RATES != 5); 840 info->flags &= ~IEEE80211_TX_CTL_RATE_CTRL_PROBE; 841 } else { 842 hdr->frame_control &= ~morefrags; 843 next_len = 0; 844 } 845 hdr->duration_id = ieee80211_duration(tx, 0, next_len); 846 hdr->seq_ctrl |= cpu_to_le16(fragnum & IEEE80211_SCTL_FRAG); 847 fragnum++; 848 } while ((skb = skb->next)); 849 850 return TX_CONTINUE; 851 } 852 853 static ieee80211_tx_result debug_noinline 854 ieee80211_tx_h_stats(struct ieee80211_tx_data *tx) 855 { 856 struct sk_buff *skb = tx->skb; 857 858 if (!tx->sta) 859 return TX_CONTINUE; 860 861 tx->sta->tx_packets++; 862 do { 863 tx->sta->tx_fragments++; 864 tx->sta->tx_bytes += skb->len; 865 } while ((skb = skb->next)); 866 867 return TX_CONTINUE; 868 } 869 870 static ieee80211_tx_result debug_noinline 871 ieee80211_tx_h_encrypt(struct ieee80211_tx_data *tx) 872 { 873 if (!tx->key) 874 return TX_CONTINUE; 875 876 switch (tx->key->conf.alg) { 877 case ALG_WEP: 878 return ieee80211_crypto_wep_encrypt(tx); 879 case ALG_TKIP: 880 return ieee80211_crypto_tkip_encrypt(tx); 881 case ALG_CCMP: 882 return ieee80211_crypto_ccmp_encrypt(tx); 883 case ALG_AES_CMAC: 884 return ieee80211_crypto_aes_cmac_encrypt(tx); 885 } 886 887 /* not reached */ 888 WARN_ON(1); 889 return TX_DROP; 890 } 891 892 static ieee80211_tx_result debug_noinline 893 ieee80211_tx_h_calculate_duration(struct ieee80211_tx_data *tx) 894 { 895 struct sk_buff *skb = tx->skb; 896 struct ieee80211_hdr *hdr; 897 int next_len; 898 bool group_addr; 899 900 do { 901 hdr = (void *) skb->data; 902 if (unlikely(ieee80211_is_pspoll(hdr->frame_control))) 903 break; /* must not overwrite AID */ 904 next_len = skb->next ? skb->next->len : 0; 905 group_addr = is_multicast_ether_addr(hdr->addr1); 906 907 hdr->duration_id = 908 ieee80211_duration(tx, group_addr, next_len); 909 } while ((skb = skb->next)); 910 911 return TX_CONTINUE; 912 } 913 914 /* actual transmit path */ 915 916 /* 917 * deal with packet injection down monitor interface 918 * with Radiotap Header -- only called for monitor mode interface 919 */ 920 static bool __ieee80211_parse_tx_radiotap(struct ieee80211_tx_data *tx, 921 struct sk_buff *skb) 922 { 923 /* 924 * this is the moment to interpret and discard the radiotap header that 925 * must be at the start of the packet injected in Monitor mode 926 * 927 * Need to take some care with endian-ness since radiotap 928 * args are little-endian 929 */ 930 931 struct ieee80211_radiotap_iterator iterator; 932 struct ieee80211_radiotap_header *rthdr = 933 (struct ieee80211_radiotap_header *) skb->data; 934 struct ieee80211_supported_band *sband; 935 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 936 int ret = ieee80211_radiotap_iterator_init(&iterator, rthdr, skb->len); 937 938 sband = tx->local->hw.wiphy->bands[tx->channel->band]; 939 940 info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT; 941 tx->flags &= ~IEEE80211_TX_FRAGMENTED; 942 943 /* 944 * for every radiotap entry that is present 945 * (ieee80211_radiotap_iterator_next returns -ENOENT when no more 946 * entries present, or -EINVAL on error) 947 */ 948 949 while (!ret) { 950 ret = ieee80211_radiotap_iterator_next(&iterator); 951 952 if (ret) 953 continue; 954 955 /* see if this argument is something we can use */ 956 switch (iterator.this_arg_index) { 957 /* 958 * You must take care when dereferencing iterator.this_arg 959 * for multibyte types... the pointer is not aligned. Use 960 * get_unaligned((type *)iterator.this_arg) to dereference 961 * iterator.this_arg for type "type" safely on all arches. 962 */ 963 case IEEE80211_RADIOTAP_FLAGS: 964 if (*iterator.this_arg & IEEE80211_RADIOTAP_F_FCS) { 965 /* 966 * this indicates that the skb we have been 967 * handed has the 32-bit FCS CRC at the end... 968 * we should react to that by snipping it off 969 * because it will be recomputed and added 970 * on transmission 971 */ 972 if (skb->len < (iterator.max_length + FCS_LEN)) 973 return false; 974 975 skb_trim(skb, skb->len - FCS_LEN); 976 } 977 if (*iterator.this_arg & IEEE80211_RADIOTAP_F_WEP) 978 info->flags &= ~IEEE80211_TX_INTFL_DONT_ENCRYPT; 979 if (*iterator.this_arg & IEEE80211_RADIOTAP_F_FRAG) 980 tx->flags |= IEEE80211_TX_FRAGMENTED; 981 break; 982 983 /* 984 * Please update the file 985 * Documentation/networking/mac80211-injection.txt 986 * when parsing new fields here. 987 */ 988 989 default: 990 break; 991 } 992 } 993 994 if (ret != -ENOENT) /* ie, if we didn't simply run out of fields */ 995 return false; 996 997 /* 998 * remove the radiotap header 999 * iterator->max_length was sanity-checked against 1000 * skb->len by iterator init 1001 */ 1002 skb_pull(skb, iterator.max_length); 1003 1004 return true; 1005 } 1006 1007 /* 1008 * initialises @tx 1009 */ 1010 static ieee80211_tx_result 1011 ieee80211_tx_prepare(struct ieee80211_sub_if_data *sdata, 1012 struct ieee80211_tx_data *tx, 1013 struct sk_buff *skb) 1014 { 1015 struct ieee80211_local *local = sdata->local; 1016 struct ieee80211_hdr *hdr; 1017 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 1018 int hdrlen, tid; 1019 u8 *qc, *state; 1020 bool queued = false; 1021 1022 memset(tx, 0, sizeof(*tx)); 1023 tx->skb = skb; 1024 tx->dev = sdata->dev; /* use original interface */ 1025 tx->local = local; 1026 tx->sdata = sdata; 1027 tx->channel = local->hw.conf.channel; 1028 /* 1029 * Set this flag (used below to indicate "automatic fragmentation"), 1030 * it will be cleared/left by radiotap as desired. 1031 */ 1032 tx->flags |= IEEE80211_TX_FRAGMENTED; 1033 1034 /* process and remove the injection radiotap header */ 1035 if (unlikely(info->flags & IEEE80211_TX_CTL_INJECTED)) { 1036 if (!__ieee80211_parse_tx_radiotap(tx, skb)) 1037 return TX_DROP; 1038 1039 /* 1040 * __ieee80211_parse_tx_radiotap has now removed 1041 * the radiotap header that was present and pre-filled 1042 * 'tx' with tx control information. 1043 */ 1044 } 1045 1046 /* 1047 * If this flag is set to true anywhere, and we get here, 1048 * we are doing the needed processing, so remove the flag 1049 * now. 1050 */ 1051 info->flags &= ~IEEE80211_TX_INTFL_NEED_TXPROCESSING; 1052 1053 hdr = (struct ieee80211_hdr *) skb->data; 1054 1055 if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) 1056 tx->sta = rcu_dereference(sdata->u.vlan.sta); 1057 if (!tx->sta) 1058 tx->sta = sta_info_get(local, hdr->addr1); 1059 1060 if (tx->sta && ieee80211_is_data_qos(hdr->frame_control) && 1061 (local->hw.flags & IEEE80211_HW_AMPDU_AGGREGATION)) { 1062 unsigned long flags; 1063 struct tid_ampdu_tx *tid_tx; 1064 1065 qc = ieee80211_get_qos_ctl(hdr); 1066 tid = *qc & IEEE80211_QOS_CTL_TID_MASK; 1067 1068 spin_lock_irqsave(&tx->sta->lock, flags); 1069 /* 1070 * XXX: This spinlock could be fairly expensive, but see the 1071 * comment in agg-tx.c:ieee80211_agg_tx_operational(). 1072 * One way to solve this would be to do something RCU-like 1073 * for managing the tid_tx struct and using atomic bitops 1074 * for the actual state -- by introducing an actual 1075 * 'operational' bit that would be possible. It would 1076 * require changing ieee80211_agg_tx_operational() to 1077 * set that bit, and changing the way tid_tx is managed 1078 * everywhere, including races between that bit and 1079 * tid_tx going away (tid_tx being added can be easily 1080 * committed to memory before the 'operational' bit). 1081 */ 1082 tid_tx = tx->sta->ampdu_mlme.tid_tx[tid]; 1083 state = &tx->sta->ampdu_mlme.tid_state_tx[tid]; 1084 if (*state == HT_AGG_STATE_OPERATIONAL) { 1085 info->flags |= IEEE80211_TX_CTL_AMPDU; 1086 } else if (*state != HT_AGG_STATE_IDLE) { 1087 /* in progress */ 1088 queued = true; 1089 info->control.vif = &sdata->vif; 1090 info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING; 1091 __skb_queue_tail(&tid_tx->pending, skb); 1092 } 1093 spin_unlock_irqrestore(&tx->sta->lock, flags); 1094 1095 if (unlikely(queued)) 1096 return TX_QUEUED; 1097 } 1098 1099 if (is_multicast_ether_addr(hdr->addr1)) { 1100 tx->flags &= ~IEEE80211_TX_UNICAST; 1101 info->flags |= IEEE80211_TX_CTL_NO_ACK; 1102 } else { 1103 tx->flags |= IEEE80211_TX_UNICAST; 1104 if (unlikely(local->wifi_wme_noack_test)) 1105 info->flags |= IEEE80211_TX_CTL_NO_ACK; 1106 else 1107 info->flags &= ~IEEE80211_TX_CTL_NO_ACK; 1108 } 1109 1110 if (tx->flags & IEEE80211_TX_FRAGMENTED) { 1111 if ((tx->flags & IEEE80211_TX_UNICAST) && 1112 skb->len + FCS_LEN > local->hw.wiphy->frag_threshold && 1113 !(info->flags & IEEE80211_TX_CTL_AMPDU)) 1114 tx->flags |= IEEE80211_TX_FRAGMENTED; 1115 else 1116 tx->flags &= ~IEEE80211_TX_FRAGMENTED; 1117 } 1118 1119 if (!tx->sta) 1120 info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT; 1121 else if (test_and_clear_sta_flags(tx->sta, WLAN_STA_CLEAR_PS_FILT)) 1122 info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT; 1123 1124 hdrlen = ieee80211_hdrlen(hdr->frame_control); 1125 if (skb->len > hdrlen + sizeof(rfc1042_header) + 2) { 1126 u8 *pos = &skb->data[hdrlen + sizeof(rfc1042_header)]; 1127 tx->ethertype = (pos[0] << 8) | pos[1]; 1128 } 1129 info->flags |= IEEE80211_TX_CTL_FIRST_FRAGMENT; 1130 1131 return TX_CONTINUE; 1132 } 1133 1134 static int __ieee80211_tx(struct ieee80211_local *local, 1135 struct sk_buff **skbp, 1136 struct sta_info *sta, 1137 bool txpending) 1138 { 1139 struct sk_buff *skb = *skbp, *next; 1140 struct ieee80211_tx_info *info; 1141 struct ieee80211_sub_if_data *sdata; 1142 unsigned long flags; 1143 int ret, len; 1144 bool fragm = false; 1145 1146 while (skb) { 1147 int q = skb_get_queue_mapping(skb); 1148 1149 spin_lock_irqsave(&local->queue_stop_reason_lock, flags); 1150 ret = IEEE80211_TX_OK; 1151 if (local->queue_stop_reasons[q] || 1152 (!txpending && !skb_queue_empty(&local->pending[q]))) 1153 ret = IEEE80211_TX_PENDING; 1154 spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags); 1155 if (ret != IEEE80211_TX_OK) 1156 return ret; 1157 1158 info = IEEE80211_SKB_CB(skb); 1159 1160 if (fragm) 1161 info->flags &= ~(IEEE80211_TX_CTL_CLEAR_PS_FILT | 1162 IEEE80211_TX_CTL_FIRST_FRAGMENT); 1163 1164 next = skb->next; 1165 len = skb->len; 1166 1167 if (next) 1168 info->flags |= IEEE80211_TX_CTL_MORE_FRAMES; 1169 1170 sdata = vif_to_sdata(info->control.vif); 1171 1172 switch (sdata->vif.type) { 1173 case NL80211_IFTYPE_MONITOR: 1174 info->control.vif = NULL; 1175 break; 1176 case NL80211_IFTYPE_AP_VLAN: 1177 info->control.vif = &container_of(sdata->bss, 1178 struct ieee80211_sub_if_data, u.ap)->vif; 1179 break; 1180 default: 1181 /* keep */ 1182 break; 1183 } 1184 1185 ret = drv_tx(local, skb); 1186 if (WARN_ON(ret != NETDEV_TX_OK && skb->len != len)) { 1187 dev_kfree_skb(skb); 1188 ret = NETDEV_TX_OK; 1189 } 1190 if (ret != NETDEV_TX_OK) { 1191 info->control.vif = &sdata->vif; 1192 return IEEE80211_TX_AGAIN; 1193 } 1194 1195 *skbp = skb = next; 1196 ieee80211_led_tx(local, 1); 1197 fragm = true; 1198 } 1199 1200 return IEEE80211_TX_OK; 1201 } 1202 1203 /* 1204 * Invoke TX handlers, return 0 on success and non-zero if the 1205 * frame was dropped or queued. 1206 */ 1207 static int invoke_tx_handlers(struct ieee80211_tx_data *tx) 1208 { 1209 struct sk_buff *skb = tx->skb; 1210 ieee80211_tx_result res = TX_DROP; 1211 1212 #define CALL_TXH(txh) \ 1213 do { \ 1214 res = txh(tx); \ 1215 if (res != TX_CONTINUE) \ 1216 goto txh_done; \ 1217 } while (0) 1218 1219 CALL_TXH(ieee80211_tx_h_check_assoc); 1220 CALL_TXH(ieee80211_tx_h_ps_buf); 1221 CALL_TXH(ieee80211_tx_h_select_key); 1222 CALL_TXH(ieee80211_tx_h_michael_mic_add); 1223 if (!(tx->local->hw.flags & IEEE80211_HW_HAS_RATE_CONTROL)) 1224 CALL_TXH(ieee80211_tx_h_rate_ctrl); 1225 CALL_TXH(ieee80211_tx_h_misc); 1226 CALL_TXH(ieee80211_tx_h_sequence); 1227 CALL_TXH(ieee80211_tx_h_fragment); 1228 /* handlers after fragment must be aware of tx info fragmentation! */ 1229 CALL_TXH(ieee80211_tx_h_stats); 1230 CALL_TXH(ieee80211_tx_h_encrypt); 1231 CALL_TXH(ieee80211_tx_h_calculate_duration); 1232 #undef CALL_TXH 1233 1234 txh_done: 1235 if (unlikely(res == TX_DROP)) { 1236 I802_DEBUG_INC(tx->local->tx_handlers_drop); 1237 while (skb) { 1238 struct sk_buff *next; 1239 1240 next = skb->next; 1241 dev_kfree_skb(skb); 1242 skb = next; 1243 } 1244 return -1; 1245 } else if (unlikely(res == TX_QUEUED)) { 1246 I802_DEBUG_INC(tx->local->tx_handlers_queued); 1247 return -1; 1248 } 1249 1250 return 0; 1251 } 1252 1253 static void ieee80211_tx(struct ieee80211_sub_if_data *sdata, 1254 struct sk_buff *skb, bool txpending) 1255 { 1256 struct ieee80211_local *local = sdata->local; 1257 struct ieee80211_tx_data tx; 1258 ieee80211_tx_result res_prepare; 1259 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 1260 struct sk_buff *next; 1261 unsigned long flags; 1262 int ret, retries; 1263 u16 queue; 1264 1265 queue = skb_get_queue_mapping(skb); 1266 1267 if (unlikely(skb->len < 10)) { 1268 dev_kfree_skb(skb); 1269 return; 1270 } 1271 1272 rcu_read_lock(); 1273 1274 /* initialises tx */ 1275 res_prepare = ieee80211_tx_prepare(sdata, &tx, skb); 1276 1277 if (unlikely(res_prepare == TX_DROP)) { 1278 dev_kfree_skb(skb); 1279 rcu_read_unlock(); 1280 return; 1281 } else if (unlikely(res_prepare == TX_QUEUED)) { 1282 rcu_read_unlock(); 1283 return; 1284 } 1285 1286 tx.channel = local->hw.conf.channel; 1287 info->band = tx.channel->band; 1288 1289 if (invoke_tx_handlers(&tx)) 1290 goto out; 1291 1292 retries = 0; 1293 retry: 1294 ret = __ieee80211_tx(local, &tx.skb, tx.sta, txpending); 1295 switch (ret) { 1296 case IEEE80211_TX_OK: 1297 break; 1298 case IEEE80211_TX_AGAIN: 1299 /* 1300 * Since there are no fragmented frames on A-MPDU 1301 * queues, there's no reason for a driver to reject 1302 * a frame there, warn and drop it. 1303 */ 1304 if (WARN_ON(info->flags & IEEE80211_TX_CTL_AMPDU)) 1305 goto drop; 1306 /* fall through */ 1307 case IEEE80211_TX_PENDING: 1308 skb = tx.skb; 1309 1310 spin_lock_irqsave(&local->queue_stop_reason_lock, flags); 1311 1312 if (local->queue_stop_reasons[queue] || 1313 !skb_queue_empty(&local->pending[queue])) { 1314 /* 1315 * if queue is stopped, queue up frames for later 1316 * transmission from the tasklet 1317 */ 1318 do { 1319 next = skb->next; 1320 skb->next = NULL; 1321 if (unlikely(txpending)) 1322 __skb_queue_head(&local->pending[queue], 1323 skb); 1324 else 1325 __skb_queue_tail(&local->pending[queue], 1326 skb); 1327 } while ((skb = next)); 1328 1329 spin_unlock_irqrestore(&local->queue_stop_reason_lock, 1330 flags); 1331 } else { 1332 /* 1333 * otherwise retry, but this is a race condition or 1334 * a driver bug (which we warn about if it persists) 1335 */ 1336 spin_unlock_irqrestore(&local->queue_stop_reason_lock, 1337 flags); 1338 1339 retries++; 1340 if (WARN(retries > 10, "tx refused but queue active\n")) 1341 goto drop; 1342 goto retry; 1343 } 1344 } 1345 out: 1346 rcu_read_unlock(); 1347 return; 1348 1349 drop: 1350 rcu_read_unlock(); 1351 1352 skb = tx.skb; 1353 while (skb) { 1354 next = skb->next; 1355 dev_kfree_skb(skb); 1356 skb = next; 1357 } 1358 } 1359 1360 /* device xmit handlers */ 1361 1362 static int ieee80211_skb_resize(struct ieee80211_local *local, 1363 struct sk_buff *skb, 1364 int head_need, bool may_encrypt) 1365 { 1366 int tail_need = 0; 1367 1368 /* 1369 * This could be optimised, devices that do full hardware 1370 * crypto (including TKIP MMIC) need no tailroom... But we 1371 * have no drivers for such devices currently. 1372 */ 1373 if (may_encrypt) { 1374 tail_need = IEEE80211_ENCRYPT_TAILROOM; 1375 tail_need -= skb_tailroom(skb); 1376 tail_need = max_t(int, tail_need, 0); 1377 } 1378 1379 if (head_need || tail_need) { 1380 /* Sorry. Can't account for this any more */ 1381 skb_orphan(skb); 1382 } 1383 1384 if (skb_header_cloned(skb)) 1385 I802_DEBUG_INC(local->tx_expand_skb_head_cloned); 1386 else 1387 I802_DEBUG_INC(local->tx_expand_skb_head); 1388 1389 if (pskb_expand_head(skb, head_need, tail_need, GFP_ATOMIC)) { 1390 printk(KERN_DEBUG "%s: failed to reallocate TX buffer\n", 1391 wiphy_name(local->hw.wiphy)); 1392 return -ENOMEM; 1393 } 1394 1395 /* update truesize too */ 1396 skb->truesize += head_need + tail_need; 1397 1398 return 0; 1399 } 1400 1401 static bool need_dynamic_ps(struct ieee80211_local *local) 1402 { 1403 /* driver doesn't support power save */ 1404 if (!(local->hw.flags & IEEE80211_HW_SUPPORTS_PS)) 1405 return false; 1406 1407 /* hardware does dynamic power save */ 1408 if (local->hw.flags & IEEE80211_HW_SUPPORTS_DYNAMIC_PS) 1409 return false; 1410 1411 /* dynamic power save disabled */ 1412 if (local->hw.conf.dynamic_ps_timeout <= 0) 1413 return false; 1414 1415 /* we are scanning, don't enable power save */ 1416 if (local->scanning) 1417 return false; 1418 1419 if (!local->ps_sdata) 1420 return false; 1421 1422 return true; 1423 } 1424 1425 static void ieee80211_xmit(struct ieee80211_sub_if_data *sdata, 1426 struct sk_buff *skb) 1427 { 1428 struct ieee80211_local *local = sdata->local; 1429 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 1430 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 1431 struct ieee80211_sub_if_data *tmp_sdata; 1432 int headroom; 1433 bool may_encrypt; 1434 1435 if (need_dynamic_ps(local)) { 1436 if (local->hw.conf.flags & IEEE80211_CONF_PS) { 1437 ieee80211_stop_queues_by_reason(&local->hw, 1438 IEEE80211_QUEUE_STOP_REASON_PS); 1439 ieee80211_queue_work(&local->hw, 1440 &local->dynamic_ps_disable_work); 1441 } 1442 1443 mod_timer(&local->dynamic_ps_timer, jiffies + 1444 msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout)); 1445 } 1446 1447 rcu_read_lock(); 1448 1449 if (unlikely(sdata->vif.type == NL80211_IFTYPE_MONITOR)) { 1450 int hdrlen; 1451 u16 len_rthdr; 1452 1453 info->flags |= IEEE80211_TX_CTL_INJECTED; 1454 1455 len_rthdr = ieee80211_get_radiotap_len(skb->data); 1456 hdr = (struct ieee80211_hdr *)(skb->data + len_rthdr); 1457 hdrlen = ieee80211_hdrlen(hdr->frame_control); 1458 1459 /* check the header is complete in the frame */ 1460 if (likely(skb->len >= len_rthdr + hdrlen)) { 1461 /* 1462 * We process outgoing injected frames that have a 1463 * local address we handle as though they are our 1464 * own frames. 1465 * This code here isn't entirely correct, the local 1466 * MAC address is not necessarily enough to find 1467 * the interface to use; for that proper VLAN/WDS 1468 * support we will need a different mechanism. 1469 */ 1470 1471 list_for_each_entry_rcu(tmp_sdata, &local->interfaces, 1472 list) { 1473 if (!netif_running(tmp_sdata->dev)) 1474 continue; 1475 if (tmp_sdata->vif.type != NL80211_IFTYPE_AP) 1476 continue; 1477 if (compare_ether_addr(tmp_sdata->dev->dev_addr, 1478 hdr->addr2) == 0) { 1479 sdata = tmp_sdata; 1480 break; 1481 } 1482 } 1483 } 1484 } 1485 1486 may_encrypt = !(info->flags & IEEE80211_TX_INTFL_DONT_ENCRYPT); 1487 1488 headroom = local->tx_headroom; 1489 if (may_encrypt) 1490 headroom += IEEE80211_ENCRYPT_HEADROOM; 1491 headroom -= skb_headroom(skb); 1492 headroom = max_t(int, 0, headroom); 1493 1494 if (ieee80211_skb_resize(local, skb, headroom, may_encrypt)) { 1495 dev_kfree_skb(skb); 1496 rcu_read_unlock(); 1497 return; 1498 } 1499 1500 info->control.vif = &sdata->vif; 1501 1502 if (ieee80211_vif_is_mesh(&sdata->vif) && 1503 ieee80211_is_data(hdr->frame_control) && 1504 !is_multicast_ether_addr(hdr->addr1)) 1505 if (mesh_nexthop_lookup(skb, sdata)) { 1506 /* skb queued: don't free */ 1507 rcu_read_unlock(); 1508 return; 1509 } 1510 1511 ieee80211_select_queue(local, skb); 1512 ieee80211_tx(sdata, skb, false); 1513 rcu_read_unlock(); 1514 } 1515 1516 netdev_tx_t ieee80211_monitor_start_xmit(struct sk_buff *skb, 1517 struct net_device *dev) 1518 { 1519 struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr); 1520 struct ieee80211_channel *chan = local->hw.conf.channel; 1521 struct ieee80211_radiotap_header *prthdr = 1522 (struct ieee80211_radiotap_header *)skb->data; 1523 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 1524 u16 len_rthdr; 1525 1526 /* 1527 * Frame injection is not allowed if beaconing is not allowed 1528 * or if we need radar detection. Beaconing is usually not allowed when 1529 * the mode or operation (Adhoc, AP, Mesh) does not support DFS. 1530 * Passive scan is also used in world regulatory domains where 1531 * your country is not known and as such it should be treated as 1532 * NO TX unless the channel is explicitly allowed in which case 1533 * your current regulatory domain would not have the passive scan 1534 * flag. 1535 * 1536 * Since AP mode uses monitor interfaces to inject/TX management 1537 * frames we can make AP mode the exception to this rule once it 1538 * supports radar detection as its implementation can deal with 1539 * radar detection by itself. We can do that later by adding a 1540 * monitor flag interfaces used for AP support. 1541 */ 1542 if ((chan->flags & (IEEE80211_CHAN_NO_IBSS | IEEE80211_CHAN_RADAR | 1543 IEEE80211_CHAN_PASSIVE_SCAN))) 1544 goto fail; 1545 1546 /* check for not even having the fixed radiotap header part */ 1547 if (unlikely(skb->len < sizeof(struct ieee80211_radiotap_header))) 1548 goto fail; /* too short to be possibly valid */ 1549 1550 /* is it a header version we can trust to find length from? */ 1551 if (unlikely(prthdr->it_version)) 1552 goto fail; /* only version 0 is supported */ 1553 1554 /* then there must be a radiotap header with a length we can use */ 1555 len_rthdr = ieee80211_get_radiotap_len(skb->data); 1556 1557 /* does the skb contain enough to deliver on the alleged length? */ 1558 if (unlikely(skb->len < len_rthdr)) 1559 goto fail; /* skb too short for claimed rt header extent */ 1560 1561 /* 1562 * fix up the pointers accounting for the radiotap 1563 * header still being in there. We are being given 1564 * a precooked IEEE80211 header so no need for 1565 * normal processing 1566 */ 1567 skb_set_mac_header(skb, len_rthdr); 1568 /* 1569 * these are just fixed to the end of the rt area since we 1570 * don't have any better information and at this point, nobody cares 1571 */ 1572 skb_set_network_header(skb, len_rthdr); 1573 skb_set_transport_header(skb, len_rthdr); 1574 1575 memset(info, 0, sizeof(*info)); 1576 1577 info->flags |= IEEE80211_TX_CTL_REQ_TX_STATUS; 1578 1579 /* pass the radiotap header up to xmit */ 1580 ieee80211_xmit(IEEE80211_DEV_TO_SUB_IF(dev), skb); 1581 return NETDEV_TX_OK; 1582 1583 fail: 1584 dev_kfree_skb(skb); 1585 return NETDEV_TX_OK; /* meaning, we dealt with the skb */ 1586 } 1587 1588 /** 1589 * ieee80211_subif_start_xmit - netif start_xmit function for Ethernet-type 1590 * subinterfaces (wlan#, WDS, and VLAN interfaces) 1591 * @skb: packet to be sent 1592 * @dev: incoming interface 1593 * 1594 * Returns: 0 on success (and frees skb in this case) or 1 on failure (skb will 1595 * not be freed, and caller is responsible for either retrying later or freeing 1596 * skb). 1597 * 1598 * This function takes in an Ethernet header and encapsulates it with suitable 1599 * IEEE 802.11 header based on which interface the packet is coming in. The 1600 * encapsulated packet will then be passed to master interface, wlan#.11, for 1601 * transmission (through low-level driver). 1602 */ 1603 netdev_tx_t ieee80211_subif_start_xmit(struct sk_buff *skb, 1604 struct net_device *dev) 1605 { 1606 struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev); 1607 struct ieee80211_local *local = sdata->local; 1608 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 1609 int ret = NETDEV_TX_BUSY, head_need; 1610 u16 ethertype, hdrlen, meshhdrlen = 0; 1611 __le16 fc; 1612 struct ieee80211_hdr hdr; 1613 struct ieee80211s_hdr mesh_hdr; 1614 const u8 *encaps_data; 1615 int encaps_len, skip_header_bytes; 1616 int nh_pos, h_pos; 1617 struct sta_info *sta = NULL; 1618 u32 sta_flags = 0; 1619 1620 if (unlikely(skb->len < ETH_HLEN)) { 1621 ret = NETDEV_TX_OK; 1622 goto fail; 1623 } 1624 1625 nh_pos = skb_network_header(skb) - skb->data; 1626 h_pos = skb_transport_header(skb) - skb->data; 1627 1628 /* convert Ethernet header to proper 802.11 header (based on 1629 * operation mode) */ 1630 ethertype = (skb->data[12] << 8) | skb->data[13]; 1631 fc = cpu_to_le16(IEEE80211_FTYPE_DATA | IEEE80211_STYPE_DATA); 1632 1633 switch (sdata->vif.type) { 1634 case NL80211_IFTYPE_AP_VLAN: 1635 rcu_read_lock(); 1636 sta = rcu_dereference(sdata->u.vlan.sta); 1637 if (sta) { 1638 fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS); 1639 /* RA TA DA SA */ 1640 memcpy(hdr.addr1, sta->sta.addr, ETH_ALEN); 1641 memcpy(hdr.addr2, dev->dev_addr, ETH_ALEN); 1642 memcpy(hdr.addr3, skb->data, ETH_ALEN); 1643 memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN); 1644 hdrlen = 30; 1645 sta_flags = get_sta_flags(sta); 1646 } 1647 rcu_read_unlock(); 1648 if (sta) 1649 break; 1650 /* fall through */ 1651 case NL80211_IFTYPE_AP: 1652 fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS); 1653 /* DA BSSID SA */ 1654 memcpy(hdr.addr1, skb->data, ETH_ALEN); 1655 memcpy(hdr.addr2, dev->dev_addr, ETH_ALEN); 1656 memcpy(hdr.addr3, skb->data + ETH_ALEN, ETH_ALEN); 1657 hdrlen = 24; 1658 break; 1659 case NL80211_IFTYPE_WDS: 1660 fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS); 1661 /* RA TA DA SA */ 1662 memcpy(hdr.addr1, sdata->u.wds.remote_addr, ETH_ALEN); 1663 memcpy(hdr.addr2, dev->dev_addr, ETH_ALEN); 1664 memcpy(hdr.addr3, skb->data, ETH_ALEN); 1665 memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN); 1666 hdrlen = 30; 1667 break; 1668 #ifdef CONFIG_MAC80211_MESH 1669 case NL80211_IFTYPE_MESH_POINT: 1670 if (!sdata->u.mesh.mshcfg.dot11MeshTTL) { 1671 /* Do not send frames with mesh_ttl == 0 */ 1672 sdata->u.mesh.mshstats.dropped_frames_ttl++; 1673 ret = NETDEV_TX_OK; 1674 goto fail; 1675 } 1676 1677 if (compare_ether_addr(dev->dev_addr, 1678 skb->data + ETH_ALEN) == 0) { 1679 hdrlen = ieee80211_fill_mesh_addresses(&hdr, &fc, 1680 skb->data, skb->data + ETH_ALEN); 1681 meshhdrlen = ieee80211_new_mesh_header(&mesh_hdr, 1682 sdata, NULL, NULL, NULL); 1683 } else { 1684 /* packet from other interface */ 1685 struct mesh_path *mppath; 1686 int is_mesh_mcast = 1; 1687 const u8 *mesh_da; 1688 1689 rcu_read_lock(); 1690 if (is_multicast_ether_addr(skb->data)) 1691 /* DA TA mSA AE:SA */ 1692 mesh_da = skb->data; 1693 else { 1694 static const u8 bcast[ETH_ALEN] = 1695 { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }; 1696 1697 mppath = mpp_path_lookup(skb->data, sdata); 1698 if (mppath) { 1699 /* RA TA mDA mSA AE:DA SA */ 1700 mesh_da = mppath->mpp; 1701 is_mesh_mcast = 0; 1702 } else { 1703 /* DA TA mSA AE:SA */ 1704 mesh_da = bcast; 1705 } 1706 } 1707 hdrlen = ieee80211_fill_mesh_addresses(&hdr, &fc, 1708 mesh_da, dev->dev_addr); 1709 rcu_read_unlock(); 1710 if (is_mesh_mcast) 1711 meshhdrlen = 1712 ieee80211_new_mesh_header(&mesh_hdr, 1713 sdata, 1714 skb->data + ETH_ALEN, 1715 NULL, 1716 NULL); 1717 else 1718 meshhdrlen = 1719 ieee80211_new_mesh_header(&mesh_hdr, 1720 sdata, 1721 NULL, 1722 skb->data, 1723 skb->data + ETH_ALEN); 1724 1725 } 1726 break; 1727 #endif 1728 case NL80211_IFTYPE_STATION: 1729 memcpy(hdr.addr1, sdata->u.mgd.bssid, ETH_ALEN); 1730 if (sdata->u.mgd.use_4addr && ethertype != ETH_P_PAE) { 1731 fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS); 1732 /* RA TA DA SA */ 1733 memcpy(hdr.addr2, dev->dev_addr, ETH_ALEN); 1734 memcpy(hdr.addr3, skb->data, ETH_ALEN); 1735 memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN); 1736 hdrlen = 30; 1737 } else { 1738 fc |= cpu_to_le16(IEEE80211_FCTL_TODS); 1739 /* BSSID SA DA */ 1740 memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN); 1741 memcpy(hdr.addr3, skb->data, ETH_ALEN); 1742 hdrlen = 24; 1743 } 1744 break; 1745 case NL80211_IFTYPE_ADHOC: 1746 /* DA SA BSSID */ 1747 memcpy(hdr.addr1, skb->data, ETH_ALEN); 1748 memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN); 1749 memcpy(hdr.addr3, sdata->u.ibss.bssid, ETH_ALEN); 1750 hdrlen = 24; 1751 break; 1752 default: 1753 ret = NETDEV_TX_OK; 1754 goto fail; 1755 } 1756 1757 /* 1758 * There's no need to try to look up the destination 1759 * if it is a multicast address (which can only happen 1760 * in AP mode) 1761 */ 1762 if (!is_multicast_ether_addr(hdr.addr1)) { 1763 rcu_read_lock(); 1764 sta = sta_info_get(local, hdr.addr1); 1765 /* XXX: in the future, use sdata to look up the sta */ 1766 if (sta && sta->sdata == sdata) 1767 sta_flags = get_sta_flags(sta); 1768 rcu_read_unlock(); 1769 } 1770 1771 /* receiver and we are QoS enabled, use a QoS type frame */ 1772 if ((sta_flags & WLAN_STA_WME) && local->hw.queues >= 4) { 1773 fc |= cpu_to_le16(IEEE80211_STYPE_QOS_DATA); 1774 hdrlen += 2; 1775 } 1776 1777 /* 1778 * Drop unicast frames to unauthorised stations unless they are 1779 * EAPOL frames from the local station. 1780 */ 1781 if (!ieee80211_vif_is_mesh(&sdata->vif) && 1782 unlikely(!is_multicast_ether_addr(hdr.addr1) && 1783 !(sta_flags & WLAN_STA_AUTHORIZED) && 1784 !(ethertype == ETH_P_PAE && 1785 compare_ether_addr(dev->dev_addr, 1786 skb->data + ETH_ALEN) == 0))) { 1787 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG 1788 if (net_ratelimit()) 1789 printk(KERN_DEBUG "%s: dropped frame to %pM" 1790 " (unauthorized port)\n", dev->name, 1791 hdr.addr1); 1792 #endif 1793 1794 I802_DEBUG_INC(local->tx_handlers_drop_unauth_port); 1795 1796 ret = NETDEV_TX_OK; 1797 goto fail; 1798 } 1799 1800 hdr.frame_control = fc; 1801 hdr.duration_id = 0; 1802 hdr.seq_ctrl = 0; 1803 1804 skip_header_bytes = ETH_HLEN; 1805 if (ethertype == ETH_P_AARP || ethertype == ETH_P_IPX) { 1806 encaps_data = bridge_tunnel_header; 1807 encaps_len = sizeof(bridge_tunnel_header); 1808 skip_header_bytes -= 2; 1809 } else if (ethertype >= 0x600) { 1810 encaps_data = rfc1042_header; 1811 encaps_len = sizeof(rfc1042_header); 1812 skip_header_bytes -= 2; 1813 } else { 1814 encaps_data = NULL; 1815 encaps_len = 0; 1816 } 1817 1818 skb_pull(skb, skip_header_bytes); 1819 nh_pos -= skip_header_bytes; 1820 h_pos -= skip_header_bytes; 1821 1822 head_need = hdrlen + encaps_len + meshhdrlen - skb_headroom(skb); 1823 1824 /* 1825 * So we need to modify the skb header and hence need a copy of 1826 * that. The head_need variable above doesn't, so far, include 1827 * the needed header space that we don't need right away. If we 1828 * can, then we don't reallocate right now but only after the 1829 * frame arrives at the master device (if it does...) 1830 * 1831 * If we cannot, however, then we will reallocate to include all 1832 * the ever needed space. Also, if we need to reallocate it anyway, 1833 * make it big enough for everything we may ever need. 1834 */ 1835 1836 if (head_need > 0 || skb_cloned(skb)) { 1837 head_need += IEEE80211_ENCRYPT_HEADROOM; 1838 head_need += local->tx_headroom; 1839 head_need = max_t(int, 0, head_need); 1840 if (ieee80211_skb_resize(local, skb, head_need, true)) 1841 goto fail; 1842 } 1843 1844 if (encaps_data) { 1845 memcpy(skb_push(skb, encaps_len), encaps_data, encaps_len); 1846 nh_pos += encaps_len; 1847 h_pos += encaps_len; 1848 } 1849 1850 if (meshhdrlen > 0) { 1851 memcpy(skb_push(skb, meshhdrlen), &mesh_hdr, meshhdrlen); 1852 nh_pos += meshhdrlen; 1853 h_pos += meshhdrlen; 1854 } 1855 1856 if (ieee80211_is_data_qos(fc)) { 1857 __le16 *qos_control; 1858 1859 qos_control = (__le16*) skb_push(skb, 2); 1860 memcpy(skb_push(skb, hdrlen - 2), &hdr, hdrlen - 2); 1861 /* 1862 * Maybe we could actually set some fields here, for now just 1863 * initialise to zero to indicate no special operation. 1864 */ 1865 *qos_control = 0; 1866 } else 1867 memcpy(skb_push(skb, hdrlen), &hdr, hdrlen); 1868 1869 nh_pos += hdrlen; 1870 h_pos += hdrlen; 1871 1872 dev->stats.tx_packets++; 1873 dev->stats.tx_bytes += skb->len; 1874 1875 /* Update skb pointers to various headers since this modified frame 1876 * is going to go through Linux networking code that may potentially 1877 * need things like pointer to IP header. */ 1878 skb_set_mac_header(skb, 0); 1879 skb_set_network_header(skb, nh_pos); 1880 skb_set_transport_header(skb, h_pos); 1881 1882 memset(info, 0, sizeof(*info)); 1883 1884 dev->trans_start = jiffies; 1885 ieee80211_xmit(sdata, skb); 1886 1887 return NETDEV_TX_OK; 1888 1889 fail: 1890 if (ret == NETDEV_TX_OK) 1891 dev_kfree_skb(skb); 1892 1893 return ret; 1894 } 1895 1896 1897 /* 1898 * ieee80211_clear_tx_pending may not be called in a context where 1899 * it is possible that it packets could come in again. 1900 */ 1901 void ieee80211_clear_tx_pending(struct ieee80211_local *local) 1902 { 1903 int i; 1904 1905 for (i = 0; i < local->hw.queues; i++) 1906 skb_queue_purge(&local->pending[i]); 1907 } 1908 1909 static bool ieee80211_tx_pending_skb(struct ieee80211_local *local, 1910 struct sk_buff *skb) 1911 { 1912 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 1913 struct ieee80211_sub_if_data *sdata; 1914 struct sta_info *sta; 1915 struct ieee80211_hdr *hdr; 1916 int ret; 1917 bool result = true; 1918 1919 sdata = vif_to_sdata(info->control.vif); 1920 1921 if (info->flags & IEEE80211_TX_INTFL_NEED_TXPROCESSING) { 1922 ieee80211_tx(sdata, skb, true); 1923 } else { 1924 hdr = (struct ieee80211_hdr *)skb->data; 1925 sta = sta_info_get(local, hdr->addr1); 1926 1927 ret = __ieee80211_tx(local, &skb, sta, true); 1928 if (ret != IEEE80211_TX_OK) 1929 result = false; 1930 } 1931 1932 return result; 1933 } 1934 1935 /* 1936 * Transmit all pending packets. Called from tasklet. 1937 */ 1938 void ieee80211_tx_pending(unsigned long data) 1939 { 1940 struct ieee80211_local *local = (struct ieee80211_local *)data; 1941 unsigned long flags; 1942 int i; 1943 bool txok; 1944 1945 rcu_read_lock(); 1946 1947 spin_lock_irqsave(&local->queue_stop_reason_lock, flags); 1948 for (i = 0; i < local->hw.queues; i++) { 1949 /* 1950 * If queue is stopped by something other than due to pending 1951 * frames, or we have no pending frames, proceed to next queue. 1952 */ 1953 if (local->queue_stop_reasons[i] || 1954 skb_queue_empty(&local->pending[i])) 1955 continue; 1956 1957 while (!skb_queue_empty(&local->pending[i])) { 1958 struct sk_buff *skb = __skb_dequeue(&local->pending[i]); 1959 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 1960 struct ieee80211_sub_if_data *sdata; 1961 1962 if (WARN_ON(!info->control.vif)) { 1963 kfree_skb(skb); 1964 continue; 1965 } 1966 1967 sdata = vif_to_sdata(info->control.vif); 1968 spin_unlock_irqrestore(&local->queue_stop_reason_lock, 1969 flags); 1970 1971 txok = ieee80211_tx_pending_skb(local, skb); 1972 if (!txok) 1973 __skb_queue_head(&local->pending[i], skb); 1974 spin_lock_irqsave(&local->queue_stop_reason_lock, 1975 flags); 1976 if (!txok) 1977 break; 1978 } 1979 } 1980 spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags); 1981 1982 rcu_read_unlock(); 1983 } 1984 1985 /* functions for drivers to get certain frames */ 1986 1987 static void ieee80211_beacon_add_tim(struct ieee80211_if_ap *bss, 1988 struct sk_buff *skb, 1989 struct beacon_data *beacon) 1990 { 1991 u8 *pos, *tim; 1992 int aid0 = 0; 1993 int i, have_bits = 0, n1, n2; 1994 1995 /* Generate bitmap for TIM only if there are any STAs in power save 1996 * mode. */ 1997 if (atomic_read(&bss->num_sta_ps) > 0) 1998 /* in the hope that this is faster than 1999 * checking byte-for-byte */ 2000 have_bits = !bitmap_empty((unsigned long*)bss->tim, 2001 IEEE80211_MAX_AID+1); 2002 2003 if (bss->dtim_count == 0) 2004 bss->dtim_count = beacon->dtim_period - 1; 2005 else 2006 bss->dtim_count--; 2007 2008 tim = pos = (u8 *) skb_put(skb, 6); 2009 *pos++ = WLAN_EID_TIM; 2010 *pos++ = 4; 2011 *pos++ = bss->dtim_count; 2012 *pos++ = beacon->dtim_period; 2013 2014 if (bss->dtim_count == 0 && !skb_queue_empty(&bss->ps_bc_buf)) 2015 aid0 = 1; 2016 2017 if (have_bits) { 2018 /* Find largest even number N1 so that bits numbered 1 through 2019 * (N1 x 8) - 1 in the bitmap are 0 and number N2 so that bits 2020 * (N2 + 1) x 8 through 2007 are 0. */ 2021 n1 = 0; 2022 for (i = 0; i < IEEE80211_MAX_TIM_LEN; i++) { 2023 if (bss->tim[i]) { 2024 n1 = i & 0xfe; 2025 break; 2026 } 2027 } 2028 n2 = n1; 2029 for (i = IEEE80211_MAX_TIM_LEN - 1; i >= n1; i--) { 2030 if (bss->tim[i]) { 2031 n2 = i; 2032 break; 2033 } 2034 } 2035 2036 /* Bitmap control */ 2037 *pos++ = n1 | aid0; 2038 /* Part Virt Bitmap */ 2039 memcpy(pos, bss->tim + n1, n2 - n1 + 1); 2040 2041 tim[1] = n2 - n1 + 4; 2042 skb_put(skb, n2 - n1); 2043 } else { 2044 *pos++ = aid0; /* Bitmap control */ 2045 *pos++ = 0; /* Part Virt Bitmap */ 2046 } 2047 } 2048 2049 struct sk_buff *ieee80211_beacon_get_tim(struct ieee80211_hw *hw, 2050 struct ieee80211_vif *vif, 2051 u16 *tim_offset, u16 *tim_length) 2052 { 2053 struct ieee80211_local *local = hw_to_local(hw); 2054 struct sk_buff *skb = NULL; 2055 struct ieee80211_tx_info *info; 2056 struct ieee80211_sub_if_data *sdata = NULL; 2057 struct ieee80211_if_ap *ap = NULL; 2058 struct beacon_data *beacon; 2059 struct ieee80211_supported_band *sband; 2060 enum ieee80211_band band = local->hw.conf.channel->band; 2061 2062 sband = local->hw.wiphy->bands[band]; 2063 2064 rcu_read_lock(); 2065 2066 sdata = vif_to_sdata(vif); 2067 2068 if (tim_offset) 2069 *tim_offset = 0; 2070 if (tim_length) 2071 *tim_length = 0; 2072 2073 if (sdata->vif.type == NL80211_IFTYPE_AP) { 2074 ap = &sdata->u.ap; 2075 beacon = rcu_dereference(ap->beacon); 2076 if (ap && beacon) { 2077 /* 2078 * headroom, head length, 2079 * tail length and maximum TIM length 2080 */ 2081 skb = dev_alloc_skb(local->tx_headroom + 2082 beacon->head_len + 2083 beacon->tail_len + 256); 2084 if (!skb) 2085 goto out; 2086 2087 skb_reserve(skb, local->tx_headroom); 2088 memcpy(skb_put(skb, beacon->head_len), beacon->head, 2089 beacon->head_len); 2090 2091 /* 2092 * Not very nice, but we want to allow the driver to call 2093 * ieee80211_beacon_get() as a response to the set_tim() 2094 * callback. That, however, is already invoked under the 2095 * sta_lock to guarantee consistent and race-free update 2096 * of the tim bitmap in mac80211 and the driver. 2097 */ 2098 if (local->tim_in_locked_section) { 2099 ieee80211_beacon_add_tim(ap, skb, beacon); 2100 } else { 2101 unsigned long flags; 2102 2103 spin_lock_irqsave(&local->sta_lock, flags); 2104 ieee80211_beacon_add_tim(ap, skb, beacon); 2105 spin_unlock_irqrestore(&local->sta_lock, flags); 2106 } 2107 2108 if (tim_offset) 2109 *tim_offset = beacon->head_len; 2110 if (tim_length) 2111 *tim_length = skb->len - beacon->head_len; 2112 2113 if (beacon->tail) 2114 memcpy(skb_put(skb, beacon->tail_len), 2115 beacon->tail, beacon->tail_len); 2116 } else 2117 goto out; 2118 } else if (sdata->vif.type == NL80211_IFTYPE_ADHOC) { 2119 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 2120 struct ieee80211_hdr *hdr; 2121 struct sk_buff *presp = rcu_dereference(ifibss->presp); 2122 2123 if (!presp) 2124 goto out; 2125 2126 skb = skb_copy(presp, GFP_ATOMIC); 2127 if (!skb) 2128 goto out; 2129 2130 hdr = (struct ieee80211_hdr *) skb->data; 2131 hdr->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 2132 IEEE80211_STYPE_BEACON); 2133 } else if (ieee80211_vif_is_mesh(&sdata->vif)) { 2134 struct ieee80211_mgmt *mgmt; 2135 u8 *pos; 2136 2137 /* headroom, head length, tail length and maximum TIM length */ 2138 skb = dev_alloc_skb(local->tx_headroom + 400); 2139 if (!skb) 2140 goto out; 2141 2142 skb_reserve(skb, local->hw.extra_tx_headroom); 2143 mgmt = (struct ieee80211_mgmt *) 2144 skb_put(skb, 24 + sizeof(mgmt->u.beacon)); 2145 memset(mgmt, 0, 24 + sizeof(mgmt->u.beacon)); 2146 mgmt->frame_control = 2147 cpu_to_le16(IEEE80211_FTYPE_MGMT | IEEE80211_STYPE_BEACON); 2148 memset(mgmt->da, 0xff, ETH_ALEN); 2149 memcpy(mgmt->sa, sdata->dev->dev_addr, ETH_ALEN); 2150 memcpy(mgmt->bssid, sdata->dev->dev_addr, ETH_ALEN); 2151 mgmt->u.beacon.beacon_int = 2152 cpu_to_le16(sdata->vif.bss_conf.beacon_int); 2153 mgmt->u.beacon.capab_info = 0x0; /* 0x0 for MPs */ 2154 2155 pos = skb_put(skb, 2); 2156 *pos++ = WLAN_EID_SSID; 2157 *pos++ = 0x0; 2158 2159 mesh_mgmt_ies_add(skb, sdata); 2160 } else { 2161 WARN_ON(1); 2162 goto out; 2163 } 2164 2165 info = IEEE80211_SKB_CB(skb); 2166 2167 info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT; 2168 info->band = band; 2169 /* 2170 * XXX: For now, always use the lowest rate 2171 */ 2172 info->control.rates[0].idx = 0; 2173 info->control.rates[0].count = 1; 2174 info->control.rates[1].idx = -1; 2175 info->control.rates[2].idx = -1; 2176 info->control.rates[3].idx = -1; 2177 info->control.rates[4].idx = -1; 2178 BUILD_BUG_ON(IEEE80211_TX_MAX_RATES != 5); 2179 2180 info->control.vif = vif; 2181 2182 info->flags |= IEEE80211_TX_CTL_NO_ACK; 2183 info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT; 2184 info->flags |= IEEE80211_TX_CTL_ASSIGN_SEQ; 2185 out: 2186 rcu_read_unlock(); 2187 return skb; 2188 } 2189 EXPORT_SYMBOL(ieee80211_beacon_get_tim); 2190 2191 void ieee80211_rts_get(struct ieee80211_hw *hw, struct ieee80211_vif *vif, 2192 const void *frame, size_t frame_len, 2193 const struct ieee80211_tx_info *frame_txctl, 2194 struct ieee80211_rts *rts) 2195 { 2196 const struct ieee80211_hdr *hdr = frame; 2197 2198 rts->frame_control = 2199 cpu_to_le16(IEEE80211_FTYPE_CTL | IEEE80211_STYPE_RTS); 2200 rts->duration = ieee80211_rts_duration(hw, vif, frame_len, 2201 frame_txctl); 2202 memcpy(rts->ra, hdr->addr1, sizeof(rts->ra)); 2203 memcpy(rts->ta, hdr->addr2, sizeof(rts->ta)); 2204 } 2205 EXPORT_SYMBOL(ieee80211_rts_get); 2206 2207 void ieee80211_ctstoself_get(struct ieee80211_hw *hw, struct ieee80211_vif *vif, 2208 const void *frame, size_t frame_len, 2209 const struct ieee80211_tx_info *frame_txctl, 2210 struct ieee80211_cts *cts) 2211 { 2212 const struct ieee80211_hdr *hdr = frame; 2213 2214 cts->frame_control = 2215 cpu_to_le16(IEEE80211_FTYPE_CTL | IEEE80211_STYPE_CTS); 2216 cts->duration = ieee80211_ctstoself_duration(hw, vif, 2217 frame_len, frame_txctl); 2218 memcpy(cts->ra, hdr->addr1, sizeof(cts->ra)); 2219 } 2220 EXPORT_SYMBOL(ieee80211_ctstoself_get); 2221 2222 struct sk_buff * 2223 ieee80211_get_buffered_bc(struct ieee80211_hw *hw, 2224 struct ieee80211_vif *vif) 2225 { 2226 struct ieee80211_local *local = hw_to_local(hw); 2227 struct sk_buff *skb = NULL; 2228 struct sta_info *sta; 2229 struct ieee80211_tx_data tx; 2230 struct ieee80211_sub_if_data *sdata; 2231 struct ieee80211_if_ap *bss = NULL; 2232 struct beacon_data *beacon; 2233 struct ieee80211_tx_info *info; 2234 2235 sdata = vif_to_sdata(vif); 2236 bss = &sdata->u.ap; 2237 2238 rcu_read_lock(); 2239 beacon = rcu_dereference(bss->beacon); 2240 2241 if (sdata->vif.type != NL80211_IFTYPE_AP || !beacon || !beacon->head) 2242 goto out; 2243 2244 if (bss->dtim_count != 0) 2245 goto out; /* send buffered bc/mc only after DTIM beacon */ 2246 2247 while (1) { 2248 skb = skb_dequeue(&bss->ps_bc_buf); 2249 if (!skb) 2250 goto out; 2251 local->total_ps_buffered--; 2252 2253 if (!skb_queue_empty(&bss->ps_bc_buf) && skb->len >= 2) { 2254 struct ieee80211_hdr *hdr = 2255 (struct ieee80211_hdr *) skb->data; 2256 /* more buffered multicast/broadcast frames ==> set 2257 * MoreData flag in IEEE 802.11 header to inform PS 2258 * STAs */ 2259 hdr->frame_control |= 2260 cpu_to_le16(IEEE80211_FCTL_MOREDATA); 2261 } 2262 2263 if (!ieee80211_tx_prepare(sdata, &tx, skb)) 2264 break; 2265 dev_kfree_skb_any(skb); 2266 } 2267 2268 info = IEEE80211_SKB_CB(skb); 2269 2270 sta = tx.sta; 2271 tx.flags |= IEEE80211_TX_PS_BUFFERED; 2272 tx.channel = local->hw.conf.channel; 2273 info->band = tx.channel->band; 2274 2275 if (invoke_tx_handlers(&tx)) 2276 skb = NULL; 2277 out: 2278 rcu_read_unlock(); 2279 2280 return skb; 2281 } 2282 EXPORT_SYMBOL(ieee80211_get_buffered_bc); 2283 2284 void ieee80211_tx_skb(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb) 2285 { 2286 skb_set_mac_header(skb, 0); 2287 skb_set_network_header(skb, 0); 2288 skb_set_transport_header(skb, 0); 2289 2290 /* 2291 * The other path calling ieee80211_xmit is from the tasklet, 2292 * and while we can handle concurrent transmissions locking 2293 * requirements are that we do not come into tx with bhs on. 2294 */ 2295 local_bh_disable(); 2296 ieee80211_xmit(sdata, skb); 2297 local_bh_enable(); 2298 } 2299