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(tx->local->sw_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 mac80211 */ 321 if (tx->local->hw.flags & IEEE80211_HW_HOST_BROADCAST_PS_BUFFERING) { 322 if (tx->local->total_ps_buffered >= TOTAL_MAX_TX_BUFFER) 323 purge_old_ps_buffers(tx->local); 324 if (skb_queue_len(&tx->sdata->bss->ps_bc_buf) >= 325 AP_MAX_BC_BUFFER) { 326 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 327 if (net_ratelimit()) { 328 printk(KERN_DEBUG "%s: BC TX buffer full - " 329 "dropping the oldest frame\n", 330 tx->dev->name); 331 } 332 #endif 333 dev_kfree_skb(skb_dequeue(&tx->sdata->bss->ps_bc_buf)); 334 } else 335 tx->local->total_ps_buffered++; 336 skb_queue_tail(&tx->sdata->bss->ps_bc_buf, tx->skb); 337 return TX_QUEUED; 338 } 339 340 /* buffered in hardware */ 341 info->flags |= IEEE80211_TX_CTL_SEND_AFTER_DTIM; 342 343 return TX_CONTINUE; 344 } 345 346 static int ieee80211_use_mfp(__le16 fc, struct sta_info *sta, 347 struct sk_buff *skb) 348 { 349 if (!ieee80211_is_mgmt(fc)) 350 return 0; 351 352 if (sta == NULL || !test_sta_flags(sta, WLAN_STA_MFP)) 353 return 0; 354 355 if (!ieee80211_is_robust_mgmt_frame((struct ieee80211_hdr *) 356 skb->data)) 357 return 0; 358 359 return 1; 360 } 361 362 static ieee80211_tx_result 363 ieee80211_tx_h_unicast_ps_buf(struct ieee80211_tx_data *tx) 364 { 365 struct sta_info *sta = tx->sta; 366 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb); 367 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data; 368 u32 staflags; 369 370 if (unlikely(!sta || ieee80211_is_probe_resp(hdr->frame_control))) 371 return TX_CONTINUE; 372 373 staflags = get_sta_flags(sta); 374 375 if (unlikely((staflags & WLAN_STA_PS) && 376 !(staflags & WLAN_STA_PSPOLL))) { 377 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 378 printk(KERN_DEBUG "STA %pM aid %d: PS buffer (entries " 379 "before %d)\n", 380 sta->sta.addr, sta->sta.aid, 381 skb_queue_len(&sta->ps_tx_buf)); 382 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 383 if (tx->local->total_ps_buffered >= TOTAL_MAX_TX_BUFFER) 384 purge_old_ps_buffers(tx->local); 385 if (skb_queue_len(&sta->ps_tx_buf) >= STA_MAX_TX_BUFFER) { 386 struct sk_buff *old = skb_dequeue(&sta->ps_tx_buf); 387 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 388 if (net_ratelimit()) { 389 printk(KERN_DEBUG "%s: STA %pM TX " 390 "buffer full - dropping oldest frame\n", 391 tx->dev->name, sta->sta.addr); 392 } 393 #endif 394 dev_kfree_skb(old); 395 } else 396 tx->local->total_ps_buffered++; 397 398 /* Queue frame to be sent after STA sends an PS Poll frame */ 399 if (skb_queue_empty(&sta->ps_tx_buf)) 400 sta_info_set_tim_bit(sta); 401 402 info->control.jiffies = jiffies; 403 info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING; 404 skb_queue_tail(&sta->ps_tx_buf, tx->skb); 405 return TX_QUEUED; 406 } 407 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 408 else if (unlikely(test_sta_flags(sta, WLAN_STA_PS))) { 409 printk(KERN_DEBUG "%s: STA %pM in PS mode, but pspoll " 410 "set -> send frame\n", tx->dev->name, 411 sta->sta.addr); 412 } 413 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 414 if (test_and_clear_sta_flags(sta, WLAN_STA_PSPOLL)) { 415 /* 416 * The sleeping station with pending data is now snoozing. 417 * It queried us for its buffered frames and will go back 418 * to deep sleep once it got everything. 419 * 420 * inform the driver, in case the hardware does powersave 421 * frame filtering and keeps a station blacklist on its own 422 * (e.g: p54), so that frames can be delivered unimpeded. 423 * 424 * Note: It should be safe to disable the filter now. 425 * As, it is really unlikely that we still have any pending 426 * frame for this station in the hw's buffers/fifos left, 427 * that is not rejected with a unsuccessful tx_status yet. 428 */ 429 430 info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT; 431 } 432 return TX_CONTINUE; 433 } 434 435 static ieee80211_tx_result debug_noinline 436 ieee80211_tx_h_ps_buf(struct ieee80211_tx_data *tx) 437 { 438 if (unlikely(tx->flags & IEEE80211_TX_PS_BUFFERED)) 439 return TX_CONTINUE; 440 441 if (tx->flags & IEEE80211_TX_UNICAST) 442 return ieee80211_tx_h_unicast_ps_buf(tx); 443 else 444 return ieee80211_tx_h_multicast_ps_buf(tx); 445 } 446 447 static ieee80211_tx_result debug_noinline 448 ieee80211_tx_h_select_key(struct ieee80211_tx_data *tx) 449 { 450 struct ieee80211_key *key = NULL; 451 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb); 452 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data; 453 454 if (unlikely(tx->skb->do_not_encrypt)) 455 tx->key = NULL; 456 else if (tx->sta && (key = rcu_dereference(tx->sta->key))) 457 tx->key = key; 458 else if (ieee80211_is_mgmt(hdr->frame_control) && 459 (key = rcu_dereference(tx->sdata->default_mgmt_key))) 460 tx->key = key; 461 else if ((key = rcu_dereference(tx->sdata->default_key))) 462 tx->key = key; 463 else if (tx->sdata->drop_unencrypted && 464 (tx->skb->protocol != cpu_to_be16(ETH_P_PAE)) && 465 !(info->flags & IEEE80211_TX_CTL_INJECTED) && 466 (!ieee80211_is_robust_mgmt_frame(hdr) || 467 (ieee80211_is_action(hdr->frame_control) && 468 tx->sta && test_sta_flags(tx->sta, WLAN_STA_MFP)))) { 469 I802_DEBUG_INC(tx->local->tx_handlers_drop_unencrypted); 470 return TX_DROP; 471 } else 472 tx->key = NULL; 473 474 if (tx->key) { 475 tx->key->tx_rx_count++; 476 /* TODO: add threshold stuff again */ 477 478 switch (tx->key->conf.alg) { 479 case ALG_WEP: 480 if (ieee80211_is_auth(hdr->frame_control)) 481 break; 482 case ALG_TKIP: 483 if (!ieee80211_is_data_present(hdr->frame_control)) 484 tx->key = NULL; 485 break; 486 case ALG_CCMP: 487 if (!ieee80211_is_data_present(hdr->frame_control) && 488 !ieee80211_use_mfp(hdr->frame_control, tx->sta, 489 tx->skb)) 490 tx->key = NULL; 491 break; 492 case ALG_AES_CMAC: 493 if (!ieee80211_is_mgmt(hdr->frame_control)) 494 tx->key = NULL; 495 break; 496 } 497 } 498 499 if (!tx->key || !(tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE)) 500 tx->skb->do_not_encrypt = 1; 501 502 return TX_CONTINUE; 503 } 504 505 static ieee80211_tx_result debug_noinline 506 ieee80211_tx_h_rate_ctrl(struct ieee80211_tx_data *tx) 507 { 508 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb); 509 struct ieee80211_hdr *hdr = (void *)tx->skb->data; 510 struct ieee80211_supported_band *sband; 511 struct ieee80211_rate *rate; 512 int i, len; 513 bool inval = false, rts = false, short_preamble = false; 514 struct ieee80211_tx_rate_control txrc; 515 516 memset(&txrc, 0, sizeof(txrc)); 517 518 sband = tx->local->hw.wiphy->bands[tx->channel->band]; 519 520 len = min_t(int, tx->skb->len + FCS_LEN, 521 tx->local->hw.wiphy->frag_threshold); 522 523 /* set up the tx rate control struct we give the RC algo */ 524 txrc.hw = local_to_hw(tx->local); 525 txrc.sband = sband; 526 txrc.bss_conf = &tx->sdata->vif.bss_conf; 527 txrc.skb = tx->skb; 528 txrc.reported_rate.idx = -1; 529 txrc.max_rate_idx = tx->sdata->max_ratectrl_rateidx; 530 531 /* set up RTS protection if desired */ 532 if (len > tx->local->hw.wiphy->rts_threshold) { 533 txrc.rts = rts = true; 534 } 535 536 /* 537 * Use short preamble if the BSS can handle it, but not for 538 * management frames unless we know the receiver can handle 539 * that -- the management frame might be to a station that 540 * just wants a probe response. 541 */ 542 if (tx->sdata->vif.bss_conf.use_short_preamble && 543 (ieee80211_is_data(hdr->frame_control) || 544 (tx->sta && test_sta_flags(tx->sta, WLAN_STA_SHORT_PREAMBLE)))) 545 txrc.short_preamble = short_preamble = true; 546 547 548 rate_control_get_rate(tx->sdata, tx->sta, &txrc); 549 550 if (unlikely(info->control.rates[0].idx < 0)) 551 return TX_DROP; 552 553 if (txrc.reported_rate.idx < 0) 554 txrc.reported_rate = info->control.rates[0]; 555 556 if (tx->sta) 557 tx->sta->last_tx_rate = txrc.reported_rate; 558 559 if (unlikely(!info->control.rates[0].count)) 560 info->control.rates[0].count = 1; 561 562 if (WARN_ON_ONCE((info->control.rates[0].count > 1) && 563 (info->flags & IEEE80211_TX_CTL_NO_ACK))) 564 info->control.rates[0].count = 1; 565 566 if (is_multicast_ether_addr(hdr->addr1)) { 567 /* 568 * XXX: verify the rate is in the basic rateset 569 */ 570 return TX_CONTINUE; 571 } 572 573 /* 574 * set up the RTS/CTS rate as the fastest basic rate 575 * that is not faster than the data rate 576 * 577 * XXX: Should this check all retry rates? 578 */ 579 if (!(info->control.rates[0].flags & IEEE80211_TX_RC_MCS)) { 580 s8 baserate = 0; 581 582 rate = &sband->bitrates[info->control.rates[0].idx]; 583 584 for (i = 0; i < sband->n_bitrates; i++) { 585 /* must be a basic rate */ 586 if (!(tx->sdata->vif.bss_conf.basic_rates & BIT(i))) 587 continue; 588 /* must not be faster than the data rate */ 589 if (sband->bitrates[i].bitrate > rate->bitrate) 590 continue; 591 /* maximum */ 592 if (sband->bitrates[baserate].bitrate < 593 sband->bitrates[i].bitrate) 594 baserate = i; 595 } 596 597 info->control.rts_cts_rate_idx = baserate; 598 } 599 600 for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) { 601 /* 602 * make sure there's no valid rate following 603 * an invalid one, just in case drivers don't 604 * take the API seriously to stop at -1. 605 */ 606 if (inval) { 607 info->control.rates[i].idx = -1; 608 continue; 609 } 610 if (info->control.rates[i].idx < 0) { 611 inval = true; 612 continue; 613 } 614 615 /* 616 * For now assume MCS is already set up correctly, this 617 * needs to be fixed. 618 */ 619 if (info->control.rates[i].flags & IEEE80211_TX_RC_MCS) { 620 WARN_ON(info->control.rates[i].idx > 76); 621 continue; 622 } 623 624 /* set up RTS protection if desired */ 625 if (rts) 626 info->control.rates[i].flags |= 627 IEEE80211_TX_RC_USE_RTS_CTS; 628 629 /* RC is busted */ 630 if (WARN_ON_ONCE(info->control.rates[i].idx >= 631 sband->n_bitrates)) { 632 info->control.rates[i].idx = -1; 633 continue; 634 } 635 636 rate = &sband->bitrates[info->control.rates[i].idx]; 637 638 /* set up short preamble */ 639 if (short_preamble && 640 rate->flags & IEEE80211_RATE_SHORT_PREAMBLE) 641 info->control.rates[i].flags |= 642 IEEE80211_TX_RC_USE_SHORT_PREAMBLE; 643 644 /* set up G protection */ 645 if (!rts && tx->sdata->vif.bss_conf.use_cts_prot && 646 rate->flags & IEEE80211_RATE_ERP_G) 647 info->control.rates[i].flags |= 648 IEEE80211_TX_RC_USE_CTS_PROTECT; 649 } 650 651 return TX_CONTINUE; 652 } 653 654 static ieee80211_tx_result debug_noinline 655 ieee80211_tx_h_misc(struct ieee80211_tx_data *tx) 656 { 657 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb); 658 659 if (tx->sta) 660 info->control.sta = &tx->sta->sta; 661 662 return TX_CONTINUE; 663 } 664 665 static ieee80211_tx_result debug_noinline 666 ieee80211_tx_h_sequence(struct ieee80211_tx_data *tx) 667 { 668 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb); 669 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data; 670 u16 *seq; 671 u8 *qc; 672 int tid; 673 674 /* 675 * Packet injection may want to control the sequence 676 * number, if we have no matching interface then we 677 * neither assign one ourselves nor ask the driver to. 678 */ 679 if (unlikely(!info->control.vif)) 680 return TX_CONTINUE; 681 682 if (unlikely(ieee80211_is_ctl(hdr->frame_control))) 683 return TX_CONTINUE; 684 685 if (ieee80211_hdrlen(hdr->frame_control) < 24) 686 return TX_CONTINUE; 687 688 /* 689 * Anything but QoS data that has a sequence number field 690 * (is long enough) gets a sequence number from the global 691 * counter. 692 */ 693 if (!ieee80211_is_data_qos(hdr->frame_control)) { 694 /* driver should assign sequence number */ 695 info->flags |= IEEE80211_TX_CTL_ASSIGN_SEQ; 696 /* for pure STA mode without beacons, we can do it */ 697 hdr->seq_ctrl = cpu_to_le16(tx->sdata->sequence_number); 698 tx->sdata->sequence_number += 0x10; 699 tx->sdata->sequence_number &= IEEE80211_SCTL_SEQ; 700 return TX_CONTINUE; 701 } 702 703 /* 704 * This should be true for injected/management frames only, for 705 * management frames we have set the IEEE80211_TX_CTL_ASSIGN_SEQ 706 * above since they are not QoS-data frames. 707 */ 708 if (!tx->sta) 709 return TX_CONTINUE; 710 711 /* include per-STA, per-TID sequence counter */ 712 713 qc = ieee80211_get_qos_ctl(hdr); 714 tid = *qc & IEEE80211_QOS_CTL_TID_MASK; 715 seq = &tx->sta->tid_seq[tid]; 716 717 hdr->seq_ctrl = cpu_to_le16(*seq); 718 719 /* Increase the sequence number. */ 720 *seq = (*seq + 0x10) & IEEE80211_SCTL_SEQ; 721 722 return TX_CONTINUE; 723 } 724 725 static int ieee80211_fragment(struct ieee80211_local *local, 726 struct sk_buff *skb, int hdrlen, 727 int frag_threshold) 728 { 729 struct sk_buff *tail = skb, *tmp; 730 int per_fragm = frag_threshold - hdrlen - FCS_LEN; 731 int pos = hdrlen + per_fragm; 732 int rem = skb->len - hdrlen - per_fragm; 733 734 if (WARN_ON(rem < 0)) 735 return -EINVAL; 736 737 while (rem) { 738 int fraglen = per_fragm; 739 740 if (fraglen > rem) 741 fraglen = rem; 742 rem -= fraglen; 743 tmp = dev_alloc_skb(local->tx_headroom + 744 frag_threshold + 745 IEEE80211_ENCRYPT_HEADROOM + 746 IEEE80211_ENCRYPT_TAILROOM); 747 if (!tmp) 748 return -ENOMEM; 749 tail->next = tmp; 750 tail = tmp; 751 skb_reserve(tmp, local->tx_headroom + 752 IEEE80211_ENCRYPT_HEADROOM); 753 /* copy control information */ 754 memcpy(tmp->cb, skb->cb, sizeof(tmp->cb)); 755 skb_copy_queue_mapping(tmp, skb); 756 tmp->priority = skb->priority; 757 tmp->do_not_encrypt = skb->do_not_encrypt; 758 tmp->dev = skb->dev; 759 tmp->iif = skb->iif; 760 761 /* copy header and data */ 762 memcpy(skb_put(tmp, hdrlen), skb->data, hdrlen); 763 memcpy(skb_put(tmp, fraglen), skb->data + pos, fraglen); 764 765 pos += fraglen; 766 } 767 768 skb->len = hdrlen + per_fragm; 769 return 0; 770 } 771 772 static ieee80211_tx_result debug_noinline 773 ieee80211_tx_h_fragment(struct ieee80211_tx_data *tx) 774 { 775 struct sk_buff *skb = tx->skb; 776 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 777 struct ieee80211_hdr *hdr = (void *)skb->data; 778 int frag_threshold = tx->local->hw.wiphy->frag_threshold; 779 int hdrlen; 780 int fragnum; 781 782 if (!(tx->flags & IEEE80211_TX_FRAGMENTED)) 783 return TX_CONTINUE; 784 785 /* 786 * Warn when submitting a fragmented A-MPDU frame and drop it. 787 * This scenario is handled in __ieee80211_tx_prepare but extra 788 * caution taken here as fragmented ampdu may cause Tx stop. 789 */ 790 if (WARN_ON(info->flags & IEEE80211_TX_CTL_AMPDU)) 791 return TX_DROP; 792 793 hdrlen = ieee80211_hdrlen(hdr->frame_control); 794 795 /* internal error, why is TX_FRAGMENTED set? */ 796 if (WARN_ON(skb->len + FCS_LEN <= frag_threshold)) 797 return TX_DROP; 798 799 /* 800 * Now fragment the frame. This will allocate all the fragments and 801 * chain them (using skb as the first fragment) to skb->next. 802 * During transmission, we will remove the successfully transmitted 803 * fragments from this list. When the low-level driver rejects one 804 * of the fragments then we will simply pretend to accept the skb 805 * but store it away as pending. 806 */ 807 if (ieee80211_fragment(tx->local, skb, hdrlen, frag_threshold)) 808 return TX_DROP; 809 810 /* update duration/seq/flags of fragments */ 811 fragnum = 0; 812 do { 813 int next_len; 814 const __le16 morefrags = cpu_to_le16(IEEE80211_FCTL_MOREFRAGS); 815 816 hdr = (void *)skb->data; 817 info = IEEE80211_SKB_CB(skb); 818 819 if (skb->next) { 820 hdr->frame_control |= morefrags; 821 next_len = skb->next->len; 822 /* 823 * No multi-rate retries for fragmented frames, that 824 * would completely throw off the NAV at other STAs. 825 */ 826 info->control.rates[1].idx = -1; 827 info->control.rates[2].idx = -1; 828 info->control.rates[3].idx = -1; 829 info->control.rates[4].idx = -1; 830 BUILD_BUG_ON(IEEE80211_TX_MAX_RATES != 5); 831 info->flags &= ~IEEE80211_TX_CTL_RATE_CTRL_PROBE; 832 } else { 833 hdr->frame_control &= ~morefrags; 834 next_len = 0; 835 } 836 hdr->duration_id = ieee80211_duration(tx, 0, next_len); 837 hdr->seq_ctrl |= cpu_to_le16(fragnum & IEEE80211_SCTL_FRAG); 838 fragnum++; 839 } while ((skb = skb->next)); 840 841 return TX_CONTINUE; 842 } 843 844 static ieee80211_tx_result debug_noinline 845 ieee80211_tx_h_encrypt(struct ieee80211_tx_data *tx) 846 { 847 if (!tx->key) 848 return TX_CONTINUE; 849 850 switch (tx->key->conf.alg) { 851 case ALG_WEP: 852 return ieee80211_crypto_wep_encrypt(tx); 853 case ALG_TKIP: 854 return ieee80211_crypto_tkip_encrypt(tx); 855 case ALG_CCMP: 856 return ieee80211_crypto_ccmp_encrypt(tx); 857 case ALG_AES_CMAC: 858 return ieee80211_crypto_aes_cmac_encrypt(tx); 859 } 860 861 /* not reached */ 862 WARN_ON(1); 863 return TX_DROP; 864 } 865 866 static ieee80211_tx_result debug_noinline 867 ieee80211_tx_h_calculate_duration(struct ieee80211_tx_data *tx) 868 { 869 struct sk_buff *skb = tx->skb; 870 struct ieee80211_hdr *hdr; 871 int next_len; 872 bool group_addr; 873 874 do { 875 hdr = (void *) skb->data; 876 if (unlikely(ieee80211_is_pspoll(hdr->frame_control))) 877 break; /* must not overwrite AID */ 878 next_len = skb->next ? skb->next->len : 0; 879 group_addr = is_multicast_ether_addr(hdr->addr1); 880 881 hdr->duration_id = 882 ieee80211_duration(tx, group_addr, next_len); 883 } while ((skb = skb->next)); 884 885 return TX_CONTINUE; 886 } 887 888 static ieee80211_tx_result debug_noinline 889 ieee80211_tx_h_stats(struct ieee80211_tx_data *tx) 890 { 891 struct sk_buff *skb = tx->skb; 892 893 if (!tx->sta) 894 return TX_CONTINUE; 895 896 tx->sta->tx_packets++; 897 do { 898 tx->sta->tx_fragments++; 899 tx->sta->tx_bytes += skb->len; 900 } while ((skb = skb->next)); 901 902 return TX_CONTINUE; 903 } 904 905 /* actual transmit path */ 906 907 /* 908 * deal with packet injection down monitor interface 909 * with Radiotap Header -- only called for monitor mode interface 910 */ 911 static bool __ieee80211_parse_tx_radiotap(struct ieee80211_tx_data *tx, 912 struct sk_buff *skb) 913 { 914 /* 915 * this is the moment to interpret and discard the radiotap header that 916 * must be at the start of the packet injected in Monitor mode 917 * 918 * Need to take some care with endian-ness since radiotap 919 * args are little-endian 920 */ 921 922 struct ieee80211_radiotap_iterator iterator; 923 struct ieee80211_radiotap_header *rthdr = 924 (struct ieee80211_radiotap_header *) skb->data; 925 struct ieee80211_supported_band *sband; 926 int ret = ieee80211_radiotap_iterator_init(&iterator, rthdr, skb->len); 927 928 sband = tx->local->hw.wiphy->bands[tx->channel->band]; 929 930 skb->do_not_encrypt = 1; 931 tx->flags &= ~IEEE80211_TX_FRAGMENTED; 932 933 /* 934 * for every radiotap entry that is present 935 * (ieee80211_radiotap_iterator_next returns -ENOENT when no more 936 * entries present, or -EINVAL on error) 937 */ 938 939 while (!ret) { 940 ret = ieee80211_radiotap_iterator_next(&iterator); 941 942 if (ret) 943 continue; 944 945 /* see if this argument is something we can use */ 946 switch (iterator.this_arg_index) { 947 /* 948 * You must take care when dereferencing iterator.this_arg 949 * for multibyte types... the pointer is not aligned. Use 950 * get_unaligned((type *)iterator.this_arg) to dereference 951 * iterator.this_arg for type "type" safely on all arches. 952 */ 953 case IEEE80211_RADIOTAP_FLAGS: 954 if (*iterator.this_arg & IEEE80211_RADIOTAP_F_FCS) { 955 /* 956 * this indicates that the skb we have been 957 * handed has the 32-bit FCS CRC at the end... 958 * we should react to that by snipping it off 959 * because it will be recomputed and added 960 * on transmission 961 */ 962 if (skb->len < (iterator.max_length + FCS_LEN)) 963 return false; 964 965 skb_trim(skb, skb->len - FCS_LEN); 966 } 967 if (*iterator.this_arg & IEEE80211_RADIOTAP_F_WEP) 968 tx->skb->do_not_encrypt = 0; 969 if (*iterator.this_arg & IEEE80211_RADIOTAP_F_FRAG) 970 tx->flags |= IEEE80211_TX_FRAGMENTED; 971 break; 972 973 /* 974 * Please update the file 975 * Documentation/networking/mac80211-injection.txt 976 * when parsing new fields here. 977 */ 978 979 default: 980 break; 981 } 982 } 983 984 if (ret != -ENOENT) /* ie, if we didn't simply run out of fields */ 985 return false; 986 987 /* 988 * remove the radiotap header 989 * iterator->max_length was sanity-checked against 990 * skb->len by iterator init 991 */ 992 skb_pull(skb, iterator.max_length); 993 994 return true; 995 } 996 997 /* 998 * initialises @tx 999 */ 1000 static ieee80211_tx_result 1001 __ieee80211_tx_prepare(struct ieee80211_tx_data *tx, 1002 struct sk_buff *skb, 1003 struct net_device *dev) 1004 { 1005 struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr); 1006 struct ieee80211_hdr *hdr; 1007 struct ieee80211_sub_if_data *sdata; 1008 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 1009 int hdrlen, tid; 1010 u8 *qc, *state; 1011 bool queued = false; 1012 1013 memset(tx, 0, sizeof(*tx)); 1014 tx->skb = skb; 1015 tx->dev = dev; /* use original interface */ 1016 tx->local = local; 1017 tx->sdata = IEEE80211_DEV_TO_SUB_IF(dev); 1018 tx->channel = local->hw.conf.channel; 1019 /* 1020 * Set this flag (used below to indicate "automatic fragmentation"), 1021 * it will be cleared/left by radiotap as desired. 1022 */ 1023 tx->flags |= IEEE80211_TX_FRAGMENTED; 1024 1025 /* process and remove the injection radiotap header */ 1026 sdata = IEEE80211_DEV_TO_SUB_IF(dev); 1027 if (unlikely(info->flags & IEEE80211_TX_CTL_INJECTED)) { 1028 if (!__ieee80211_parse_tx_radiotap(tx, skb)) 1029 return TX_DROP; 1030 1031 /* 1032 * __ieee80211_parse_tx_radiotap has now removed 1033 * the radiotap header that was present and pre-filled 1034 * 'tx' with tx control information. 1035 */ 1036 } 1037 1038 /* 1039 * If this flag is set to true anywhere, and we get here, 1040 * we are doing the needed processing, so remove the flag 1041 * now. 1042 */ 1043 info->flags &= ~IEEE80211_TX_INTFL_NEED_TXPROCESSING; 1044 1045 hdr = (struct ieee80211_hdr *) skb->data; 1046 1047 tx->sta = sta_info_get(local, hdr->addr1); 1048 1049 if (tx->sta && ieee80211_is_data_qos(hdr->frame_control) && 1050 (local->hw.flags & IEEE80211_HW_AMPDU_AGGREGATION)) { 1051 unsigned long flags; 1052 struct tid_ampdu_tx *tid_tx; 1053 1054 qc = ieee80211_get_qos_ctl(hdr); 1055 tid = *qc & IEEE80211_QOS_CTL_TID_MASK; 1056 1057 spin_lock_irqsave(&tx->sta->lock, flags); 1058 /* 1059 * XXX: This spinlock could be fairly expensive, but see the 1060 * comment in agg-tx.c:ieee80211_agg_tx_operational(). 1061 * One way to solve this would be to do something RCU-like 1062 * for managing the tid_tx struct and using atomic bitops 1063 * for the actual state -- by introducing an actual 1064 * 'operational' bit that would be possible. It would 1065 * require changing ieee80211_agg_tx_operational() to 1066 * set that bit, and changing the way tid_tx is managed 1067 * everywhere, including races between that bit and 1068 * tid_tx going away (tid_tx being added can be easily 1069 * committed to memory before the 'operational' bit). 1070 */ 1071 tid_tx = tx->sta->ampdu_mlme.tid_tx[tid]; 1072 state = &tx->sta->ampdu_mlme.tid_state_tx[tid]; 1073 if (*state == HT_AGG_STATE_OPERATIONAL) { 1074 info->flags |= IEEE80211_TX_CTL_AMPDU; 1075 } else if (*state != HT_AGG_STATE_IDLE) { 1076 /* in progress */ 1077 queued = true; 1078 info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING; 1079 __skb_queue_tail(&tid_tx->pending, skb); 1080 } 1081 spin_unlock_irqrestore(&tx->sta->lock, flags); 1082 1083 if (unlikely(queued)) 1084 return TX_QUEUED; 1085 } 1086 1087 if (is_multicast_ether_addr(hdr->addr1)) { 1088 tx->flags &= ~IEEE80211_TX_UNICAST; 1089 info->flags |= IEEE80211_TX_CTL_NO_ACK; 1090 } else { 1091 tx->flags |= IEEE80211_TX_UNICAST; 1092 if (unlikely(local->wifi_wme_noack_test)) 1093 info->flags |= IEEE80211_TX_CTL_NO_ACK; 1094 else 1095 info->flags &= ~IEEE80211_TX_CTL_NO_ACK; 1096 } 1097 1098 if (tx->flags & IEEE80211_TX_FRAGMENTED) { 1099 if ((tx->flags & IEEE80211_TX_UNICAST) && 1100 skb->len + FCS_LEN > local->hw.wiphy->frag_threshold && 1101 !(info->flags & IEEE80211_TX_CTL_AMPDU)) 1102 tx->flags |= IEEE80211_TX_FRAGMENTED; 1103 else 1104 tx->flags &= ~IEEE80211_TX_FRAGMENTED; 1105 } 1106 1107 if (!tx->sta) 1108 info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT; 1109 else if (test_and_clear_sta_flags(tx->sta, WLAN_STA_CLEAR_PS_FILT)) 1110 info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT; 1111 1112 hdrlen = ieee80211_hdrlen(hdr->frame_control); 1113 if (skb->len > hdrlen + sizeof(rfc1042_header) + 2) { 1114 u8 *pos = &skb->data[hdrlen + sizeof(rfc1042_header)]; 1115 tx->ethertype = (pos[0] << 8) | pos[1]; 1116 } 1117 info->flags |= IEEE80211_TX_CTL_FIRST_FRAGMENT; 1118 1119 return TX_CONTINUE; 1120 } 1121 1122 /* 1123 * NB: @tx is uninitialised when passed in here 1124 */ 1125 static int ieee80211_tx_prepare(struct ieee80211_local *local, 1126 struct ieee80211_tx_data *tx, 1127 struct sk_buff *skb) 1128 { 1129 struct net_device *dev; 1130 1131 dev = dev_get_by_index(&init_net, skb->iif); 1132 if (unlikely(dev && !is_ieee80211_device(local, dev))) { 1133 dev_put(dev); 1134 dev = NULL; 1135 } 1136 if (unlikely(!dev)) 1137 return -ENODEV; 1138 /* 1139 * initialises tx with control 1140 * 1141 * return value is safe to ignore here because this function 1142 * can only be invoked for multicast frames 1143 * 1144 * XXX: clean up 1145 */ 1146 __ieee80211_tx_prepare(tx, skb, dev); 1147 dev_put(dev); 1148 return 0; 1149 } 1150 1151 static int __ieee80211_tx(struct ieee80211_local *local, 1152 struct sk_buff **skbp, 1153 struct sta_info *sta) 1154 { 1155 struct sk_buff *skb = *skbp, *next; 1156 struct ieee80211_tx_info *info; 1157 int ret, len; 1158 bool fragm = false; 1159 1160 local->mdev->trans_start = jiffies; 1161 1162 while (skb) { 1163 if (ieee80211_queue_stopped(&local->hw, 1164 skb_get_queue_mapping(skb))) 1165 return IEEE80211_TX_PENDING; 1166 1167 info = IEEE80211_SKB_CB(skb); 1168 1169 if (fragm) 1170 info->flags &= ~(IEEE80211_TX_CTL_CLEAR_PS_FILT | 1171 IEEE80211_TX_CTL_FIRST_FRAGMENT); 1172 1173 next = skb->next; 1174 len = skb->len; 1175 ret = drv_tx(local, skb); 1176 if (WARN_ON(ret != NETDEV_TX_OK && skb->len != len)) { 1177 dev_kfree_skb(skb); 1178 ret = NETDEV_TX_OK; 1179 } 1180 if (ret != NETDEV_TX_OK) 1181 return IEEE80211_TX_AGAIN; 1182 *skbp = skb = next; 1183 ieee80211_led_tx(local, 1); 1184 fragm = true; 1185 } 1186 1187 return IEEE80211_TX_OK; 1188 } 1189 1190 /* 1191 * Invoke TX handlers, return 0 on success and non-zero if the 1192 * frame was dropped or queued. 1193 */ 1194 static int invoke_tx_handlers(struct ieee80211_tx_data *tx) 1195 { 1196 struct sk_buff *skb = tx->skb; 1197 ieee80211_tx_result res = TX_DROP; 1198 1199 #define CALL_TXH(txh) \ 1200 res = txh(tx); \ 1201 if (res != TX_CONTINUE) \ 1202 goto txh_done; 1203 1204 CALL_TXH(ieee80211_tx_h_check_assoc) 1205 CALL_TXH(ieee80211_tx_h_ps_buf) 1206 CALL_TXH(ieee80211_tx_h_select_key) 1207 CALL_TXH(ieee80211_tx_h_michael_mic_add) 1208 CALL_TXH(ieee80211_tx_h_rate_ctrl) 1209 CALL_TXH(ieee80211_tx_h_misc) 1210 CALL_TXH(ieee80211_tx_h_sequence) 1211 CALL_TXH(ieee80211_tx_h_fragment) 1212 /* handlers after fragment must be aware of tx info fragmentation! */ 1213 CALL_TXH(ieee80211_tx_h_encrypt) 1214 CALL_TXH(ieee80211_tx_h_calculate_duration) 1215 CALL_TXH(ieee80211_tx_h_stats) 1216 #undef CALL_TXH 1217 1218 txh_done: 1219 if (unlikely(res == TX_DROP)) { 1220 I802_DEBUG_INC(tx->local->tx_handlers_drop); 1221 while (skb) { 1222 struct sk_buff *next; 1223 1224 next = skb->next; 1225 dev_kfree_skb(skb); 1226 skb = next; 1227 } 1228 return -1; 1229 } else if (unlikely(res == TX_QUEUED)) { 1230 I802_DEBUG_INC(tx->local->tx_handlers_queued); 1231 return -1; 1232 } 1233 1234 return 0; 1235 } 1236 1237 static void ieee80211_tx(struct net_device *dev, struct sk_buff *skb, 1238 bool txpending) 1239 { 1240 struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr); 1241 struct ieee80211_tx_data tx; 1242 ieee80211_tx_result res_prepare; 1243 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 1244 struct sk_buff *next; 1245 unsigned long flags; 1246 int ret, retries; 1247 u16 queue; 1248 1249 queue = skb_get_queue_mapping(skb); 1250 1251 WARN_ON(!txpending && !skb_queue_empty(&local->pending[queue])); 1252 1253 if (unlikely(skb->len < 10)) { 1254 dev_kfree_skb(skb); 1255 return; 1256 } 1257 1258 rcu_read_lock(); 1259 1260 /* initialises tx */ 1261 res_prepare = __ieee80211_tx_prepare(&tx, skb, dev); 1262 1263 if (unlikely(res_prepare == TX_DROP)) { 1264 dev_kfree_skb(skb); 1265 rcu_read_unlock(); 1266 return; 1267 } else if (unlikely(res_prepare == TX_QUEUED)) { 1268 rcu_read_unlock(); 1269 return; 1270 } 1271 1272 tx.channel = local->hw.conf.channel; 1273 info->band = tx.channel->band; 1274 1275 if (invoke_tx_handlers(&tx)) 1276 goto out; 1277 1278 retries = 0; 1279 retry: 1280 ret = __ieee80211_tx(local, &tx.skb, tx.sta); 1281 switch (ret) { 1282 case IEEE80211_TX_OK: 1283 break; 1284 case IEEE80211_TX_AGAIN: 1285 /* 1286 * Since there are no fragmented frames on A-MPDU 1287 * queues, there's no reason for a driver to reject 1288 * a frame there, warn and drop it. 1289 */ 1290 if (WARN_ON(info->flags & IEEE80211_TX_CTL_AMPDU)) 1291 goto drop; 1292 /* fall through */ 1293 case IEEE80211_TX_PENDING: 1294 skb = tx.skb; 1295 1296 spin_lock_irqsave(&local->queue_stop_reason_lock, flags); 1297 1298 if (__netif_subqueue_stopped(local->mdev, queue)) { 1299 do { 1300 next = skb->next; 1301 skb->next = NULL; 1302 if (unlikely(txpending)) 1303 skb_queue_head(&local->pending[queue], 1304 skb); 1305 else 1306 skb_queue_tail(&local->pending[queue], 1307 skb); 1308 } while ((skb = next)); 1309 1310 /* 1311 * Make sure nobody will enable the queue on us 1312 * (without going through the tasklet) nor disable the 1313 * netdev queue underneath the pending handling code. 1314 */ 1315 __set_bit(IEEE80211_QUEUE_STOP_REASON_PENDING, 1316 &local->queue_stop_reasons[queue]); 1317 1318 spin_unlock_irqrestore(&local->queue_stop_reason_lock, 1319 flags); 1320 } else { 1321 spin_unlock_irqrestore(&local->queue_stop_reason_lock, 1322 flags); 1323 1324 retries++; 1325 if (WARN(retries > 10, "tx refused but queue active")) 1326 goto drop; 1327 goto retry; 1328 } 1329 } 1330 out: 1331 rcu_read_unlock(); 1332 return; 1333 1334 drop: 1335 rcu_read_unlock(); 1336 1337 skb = tx.skb; 1338 while (skb) { 1339 next = skb->next; 1340 dev_kfree_skb(skb); 1341 skb = next; 1342 } 1343 } 1344 1345 /* device xmit handlers */ 1346 1347 static int ieee80211_skb_resize(struct ieee80211_local *local, 1348 struct sk_buff *skb, 1349 int head_need, bool may_encrypt) 1350 { 1351 int tail_need = 0; 1352 1353 /* 1354 * This could be optimised, devices that do full hardware 1355 * crypto (including TKIP MMIC) need no tailroom... But we 1356 * have no drivers for such devices currently. 1357 */ 1358 if (may_encrypt) { 1359 tail_need = IEEE80211_ENCRYPT_TAILROOM; 1360 tail_need -= skb_tailroom(skb); 1361 tail_need = max_t(int, tail_need, 0); 1362 } 1363 1364 if (head_need || tail_need) { 1365 /* Sorry. Can't account for this any more */ 1366 skb_orphan(skb); 1367 } 1368 1369 if (skb_header_cloned(skb)) 1370 I802_DEBUG_INC(local->tx_expand_skb_head_cloned); 1371 else 1372 I802_DEBUG_INC(local->tx_expand_skb_head); 1373 1374 if (pskb_expand_head(skb, head_need, tail_need, GFP_ATOMIC)) { 1375 printk(KERN_DEBUG "%s: failed to reallocate TX buffer\n", 1376 wiphy_name(local->hw.wiphy)); 1377 return -ENOMEM; 1378 } 1379 1380 /* update truesize too */ 1381 skb->truesize += head_need + tail_need; 1382 1383 return 0; 1384 } 1385 1386 int ieee80211_master_start_xmit(struct sk_buff *skb, struct net_device *dev) 1387 { 1388 struct ieee80211_master_priv *mpriv = netdev_priv(dev); 1389 struct ieee80211_local *local = mpriv->local; 1390 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 1391 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 1392 struct net_device *odev = NULL; 1393 struct ieee80211_sub_if_data *osdata; 1394 int headroom; 1395 bool may_encrypt; 1396 enum { 1397 NOT_MONITOR, 1398 FOUND_SDATA, 1399 UNKNOWN_ADDRESS, 1400 } monitor_iface = NOT_MONITOR; 1401 1402 if (skb->iif) 1403 odev = dev_get_by_index(&init_net, skb->iif); 1404 if (unlikely(odev && !is_ieee80211_device(local, odev))) { 1405 dev_put(odev); 1406 odev = NULL; 1407 } 1408 if (unlikely(!odev)) { 1409 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG 1410 printk(KERN_DEBUG "%s: Discarded packet with nonexistent " 1411 "originating device\n", dev->name); 1412 #endif 1413 dev_kfree_skb(skb); 1414 return NETDEV_TX_OK; 1415 } 1416 1417 if ((local->hw.flags & IEEE80211_HW_PS_NULLFUNC_STACK) && 1418 local->hw.conf.dynamic_ps_timeout > 0 && 1419 !local->sw_scanning && !local->hw_scanning && local->ps_sdata) { 1420 if (local->hw.conf.flags & IEEE80211_CONF_PS) { 1421 ieee80211_stop_queues_by_reason(&local->hw, 1422 IEEE80211_QUEUE_STOP_REASON_PS); 1423 queue_work(local->hw.workqueue, 1424 &local->dynamic_ps_disable_work); 1425 } 1426 1427 mod_timer(&local->dynamic_ps_timer, jiffies + 1428 msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout)); 1429 } 1430 1431 memset(info, 0, sizeof(*info)); 1432 1433 info->flags |= IEEE80211_TX_CTL_REQ_TX_STATUS; 1434 1435 osdata = IEEE80211_DEV_TO_SUB_IF(odev); 1436 1437 if (ieee80211_vif_is_mesh(&osdata->vif) && 1438 ieee80211_is_data(hdr->frame_control)) { 1439 if (is_multicast_ether_addr(hdr->addr3)) 1440 memcpy(hdr->addr1, hdr->addr3, ETH_ALEN); 1441 else 1442 if (mesh_nexthop_lookup(skb, osdata)) { 1443 dev_put(odev); 1444 return NETDEV_TX_OK; 1445 } 1446 if (memcmp(odev->dev_addr, hdr->addr4, ETH_ALEN) != 0) 1447 IEEE80211_IFSTA_MESH_CTR_INC(&osdata->u.mesh, 1448 fwded_frames); 1449 } else if (unlikely(osdata->vif.type == NL80211_IFTYPE_MONITOR)) { 1450 struct ieee80211_sub_if_data *sdata; 1451 int hdrlen; 1452 u16 len_rthdr; 1453 1454 info->flags |= IEEE80211_TX_CTL_INJECTED; 1455 monitor_iface = UNKNOWN_ADDRESS; 1456 1457 len_rthdr = ieee80211_get_radiotap_len(skb->data); 1458 hdr = (struct ieee80211_hdr *)skb->data + len_rthdr; 1459 hdrlen = ieee80211_hdrlen(hdr->frame_control); 1460 1461 /* check the header is complete in the frame */ 1462 if (likely(skb->len >= len_rthdr + hdrlen)) { 1463 /* 1464 * We process outgoing injected frames that have a 1465 * local address we handle as though they are our 1466 * own frames. 1467 * This code here isn't entirely correct, the local 1468 * MAC address is not necessarily enough to find 1469 * the interface to use; for that proper VLAN/WDS 1470 * support we will need a different mechanism. 1471 */ 1472 1473 rcu_read_lock(); 1474 list_for_each_entry_rcu(sdata, &local->interfaces, 1475 list) { 1476 if (!netif_running(sdata->dev)) 1477 continue; 1478 if (sdata->vif.type != NL80211_IFTYPE_AP) 1479 continue; 1480 if (compare_ether_addr(sdata->dev->dev_addr, 1481 hdr->addr2)) { 1482 dev_hold(sdata->dev); 1483 dev_put(odev); 1484 osdata = sdata; 1485 odev = osdata->dev; 1486 skb->iif = sdata->dev->ifindex; 1487 monitor_iface = FOUND_SDATA; 1488 break; 1489 } 1490 } 1491 rcu_read_unlock(); 1492 } 1493 } 1494 1495 may_encrypt = !skb->do_not_encrypt; 1496 1497 headroom = osdata->local->tx_headroom; 1498 if (may_encrypt) 1499 headroom += IEEE80211_ENCRYPT_HEADROOM; 1500 headroom -= skb_headroom(skb); 1501 headroom = max_t(int, 0, headroom); 1502 1503 if (ieee80211_skb_resize(osdata->local, skb, headroom, may_encrypt)) { 1504 dev_kfree_skb(skb); 1505 dev_put(odev); 1506 return NETDEV_TX_OK; 1507 } 1508 1509 if (osdata->vif.type == NL80211_IFTYPE_AP_VLAN) 1510 osdata = container_of(osdata->bss, 1511 struct ieee80211_sub_if_data, 1512 u.ap); 1513 if (likely(monitor_iface != UNKNOWN_ADDRESS)) 1514 info->control.vif = &osdata->vif; 1515 1516 ieee80211_tx(odev, skb, false); 1517 dev_put(odev); 1518 1519 return NETDEV_TX_OK; 1520 } 1521 1522 int ieee80211_monitor_start_xmit(struct sk_buff *skb, 1523 struct net_device *dev) 1524 { 1525 struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr); 1526 struct ieee80211_channel *chan = local->hw.conf.channel; 1527 struct ieee80211_radiotap_header *prthdr = 1528 (struct ieee80211_radiotap_header *)skb->data; 1529 u16 len_rthdr; 1530 1531 /* 1532 * Frame injection is not allowed if beaconing is not allowed 1533 * or if we need radar detection. Beaconing is usually not allowed when 1534 * the mode or operation (Adhoc, AP, Mesh) does not support DFS. 1535 * Passive scan is also used in world regulatory domains where 1536 * your country is not known and as such it should be treated as 1537 * NO TX unless the channel is explicitly allowed in which case 1538 * your current regulatory domain would not have the passive scan 1539 * flag. 1540 * 1541 * Since AP mode uses monitor interfaces to inject/TX management 1542 * frames we can make AP mode the exception to this rule once it 1543 * supports radar detection as its implementation can deal with 1544 * radar detection by itself. We can do that later by adding a 1545 * monitor flag interfaces used for AP support. 1546 */ 1547 if ((chan->flags & (IEEE80211_CHAN_NO_IBSS | IEEE80211_CHAN_RADAR | 1548 IEEE80211_CHAN_PASSIVE_SCAN))) 1549 goto fail; 1550 1551 /* check for not even having the fixed radiotap header part */ 1552 if (unlikely(skb->len < sizeof(struct ieee80211_radiotap_header))) 1553 goto fail; /* too short to be possibly valid */ 1554 1555 /* is it a header version we can trust to find length from? */ 1556 if (unlikely(prthdr->it_version)) 1557 goto fail; /* only version 0 is supported */ 1558 1559 /* then there must be a radiotap header with a length we can use */ 1560 len_rthdr = ieee80211_get_radiotap_len(skb->data); 1561 1562 /* does the skb contain enough to deliver on the alleged length? */ 1563 if (unlikely(skb->len < len_rthdr)) 1564 goto fail; /* skb too short for claimed rt header extent */ 1565 1566 skb->dev = local->mdev; 1567 1568 /* needed because we set skb device to master */ 1569 skb->iif = dev->ifindex; 1570 1571 /* sometimes we do encrypt injected frames, will be fixed 1572 * up in radiotap parser if not wanted */ 1573 skb->do_not_encrypt = 0; 1574 1575 /* 1576 * fix up the pointers accounting for the radiotap 1577 * header still being in there. We are being given 1578 * a precooked IEEE80211 header so no need for 1579 * normal processing 1580 */ 1581 skb_set_mac_header(skb, len_rthdr); 1582 /* 1583 * these are just fixed to the end of the rt area since we 1584 * don't have any better information and at this point, nobody cares 1585 */ 1586 skb_set_network_header(skb, len_rthdr); 1587 skb_set_transport_header(skb, len_rthdr); 1588 1589 /* pass the radiotap header up to the next stage intact */ 1590 dev_queue_xmit(skb); 1591 return NETDEV_TX_OK; 1592 1593 fail: 1594 dev_kfree_skb(skb); 1595 return NETDEV_TX_OK; /* meaning, we dealt with the skb */ 1596 } 1597 1598 /** 1599 * ieee80211_subif_start_xmit - netif start_xmit function for Ethernet-type 1600 * subinterfaces (wlan#, WDS, and VLAN interfaces) 1601 * @skb: packet to be sent 1602 * @dev: incoming interface 1603 * 1604 * Returns: 0 on success (and frees skb in this case) or 1 on failure (skb will 1605 * not be freed, and caller is responsible for either retrying later or freeing 1606 * skb). 1607 * 1608 * This function takes in an Ethernet header and encapsulates it with suitable 1609 * IEEE 802.11 header based on which interface the packet is coming in. The 1610 * encapsulated packet will then be passed to master interface, wlan#.11, for 1611 * transmission (through low-level driver). 1612 */ 1613 int ieee80211_subif_start_xmit(struct sk_buff *skb, 1614 struct net_device *dev) 1615 { 1616 struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev); 1617 struct ieee80211_local *local = sdata->local; 1618 int ret = NETDEV_TX_BUSY, head_need; 1619 u16 ethertype, hdrlen, meshhdrlen = 0; 1620 __le16 fc; 1621 struct ieee80211_hdr hdr; 1622 struct ieee80211s_hdr mesh_hdr; 1623 const u8 *encaps_data; 1624 int encaps_len, skip_header_bytes; 1625 int nh_pos, h_pos; 1626 struct sta_info *sta; 1627 u32 sta_flags = 0; 1628 1629 if (unlikely(skb->len < ETH_HLEN)) { 1630 ret = 0; 1631 goto fail; 1632 } 1633 1634 nh_pos = skb_network_header(skb) - skb->data; 1635 h_pos = skb_transport_header(skb) - skb->data; 1636 1637 /* convert Ethernet header to proper 802.11 header (based on 1638 * operation mode) */ 1639 ethertype = (skb->data[12] << 8) | skb->data[13]; 1640 fc = cpu_to_le16(IEEE80211_FTYPE_DATA | IEEE80211_STYPE_DATA); 1641 1642 switch (sdata->vif.type) { 1643 case NL80211_IFTYPE_AP: 1644 case NL80211_IFTYPE_AP_VLAN: 1645 fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS); 1646 /* DA BSSID SA */ 1647 memcpy(hdr.addr1, skb->data, ETH_ALEN); 1648 memcpy(hdr.addr2, dev->dev_addr, ETH_ALEN); 1649 memcpy(hdr.addr3, skb->data + ETH_ALEN, ETH_ALEN); 1650 hdrlen = 24; 1651 break; 1652 case NL80211_IFTYPE_WDS: 1653 fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS); 1654 /* RA TA DA SA */ 1655 memcpy(hdr.addr1, sdata->u.wds.remote_addr, ETH_ALEN); 1656 memcpy(hdr.addr2, dev->dev_addr, ETH_ALEN); 1657 memcpy(hdr.addr3, skb->data, ETH_ALEN); 1658 memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN); 1659 hdrlen = 30; 1660 break; 1661 #ifdef CONFIG_MAC80211_MESH 1662 case NL80211_IFTYPE_MESH_POINT: 1663 fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS); 1664 if (!sdata->u.mesh.mshcfg.dot11MeshTTL) { 1665 /* Do not send frames with mesh_ttl == 0 */ 1666 sdata->u.mesh.mshstats.dropped_frames_ttl++; 1667 ret = 0; 1668 goto fail; 1669 } 1670 memset(&mesh_hdr, 0, sizeof(mesh_hdr)); 1671 1672 if (compare_ether_addr(dev->dev_addr, 1673 skb->data + ETH_ALEN) == 0) { 1674 /* RA TA DA SA */ 1675 memset(hdr.addr1, 0, ETH_ALEN); 1676 memcpy(hdr.addr2, dev->dev_addr, ETH_ALEN); 1677 memcpy(hdr.addr3, skb->data, ETH_ALEN); 1678 memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN); 1679 meshhdrlen = ieee80211_new_mesh_header(&mesh_hdr, sdata); 1680 } else { 1681 /* packet from other interface */ 1682 struct mesh_path *mppath; 1683 1684 memset(hdr.addr1, 0, ETH_ALEN); 1685 memcpy(hdr.addr2, dev->dev_addr, ETH_ALEN); 1686 memcpy(hdr.addr4, dev->dev_addr, ETH_ALEN); 1687 1688 if (is_multicast_ether_addr(skb->data)) 1689 memcpy(hdr.addr3, skb->data, ETH_ALEN); 1690 else { 1691 rcu_read_lock(); 1692 mppath = mpp_path_lookup(skb->data, sdata); 1693 if (mppath) 1694 memcpy(hdr.addr3, mppath->mpp, ETH_ALEN); 1695 else 1696 memset(hdr.addr3, 0xff, ETH_ALEN); 1697 rcu_read_unlock(); 1698 } 1699 1700 mesh_hdr.flags |= MESH_FLAGS_AE_A5_A6; 1701 mesh_hdr.ttl = sdata->u.mesh.mshcfg.dot11MeshTTL; 1702 put_unaligned(cpu_to_le32(sdata->u.mesh.mesh_seqnum), &mesh_hdr.seqnum); 1703 memcpy(mesh_hdr.eaddr1, skb->data, ETH_ALEN); 1704 memcpy(mesh_hdr.eaddr2, skb->data + ETH_ALEN, ETH_ALEN); 1705 sdata->u.mesh.mesh_seqnum++; 1706 meshhdrlen = 18; 1707 } 1708 hdrlen = 30; 1709 break; 1710 #endif 1711 case NL80211_IFTYPE_STATION: 1712 fc |= cpu_to_le16(IEEE80211_FCTL_TODS); 1713 /* BSSID SA DA */ 1714 memcpy(hdr.addr1, sdata->u.mgd.bssid, ETH_ALEN); 1715 memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN); 1716 memcpy(hdr.addr3, skb->data, ETH_ALEN); 1717 hdrlen = 24; 1718 break; 1719 case NL80211_IFTYPE_ADHOC: 1720 /* DA SA BSSID */ 1721 memcpy(hdr.addr1, skb->data, ETH_ALEN); 1722 memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN); 1723 memcpy(hdr.addr3, sdata->u.ibss.bssid, ETH_ALEN); 1724 hdrlen = 24; 1725 break; 1726 default: 1727 ret = 0; 1728 goto fail; 1729 } 1730 1731 /* 1732 * There's no need to try to look up the destination 1733 * if it is a multicast address (which can only happen 1734 * in AP mode) 1735 */ 1736 if (!is_multicast_ether_addr(hdr.addr1)) { 1737 rcu_read_lock(); 1738 sta = sta_info_get(local, hdr.addr1); 1739 if (sta) 1740 sta_flags = get_sta_flags(sta); 1741 rcu_read_unlock(); 1742 } 1743 1744 /* receiver and we are QoS enabled, use a QoS type frame */ 1745 if ((sta_flags & WLAN_STA_WME) && local->hw.queues >= 4) { 1746 fc |= cpu_to_le16(IEEE80211_STYPE_QOS_DATA); 1747 hdrlen += 2; 1748 } 1749 1750 /* 1751 * Drop unicast frames to unauthorised stations unless they are 1752 * EAPOL frames from the local station. 1753 */ 1754 if (!ieee80211_vif_is_mesh(&sdata->vif) && 1755 unlikely(!is_multicast_ether_addr(hdr.addr1) && 1756 !(sta_flags & WLAN_STA_AUTHORIZED) && 1757 !(ethertype == ETH_P_PAE && 1758 compare_ether_addr(dev->dev_addr, 1759 skb->data + ETH_ALEN) == 0))) { 1760 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG 1761 if (net_ratelimit()) 1762 printk(KERN_DEBUG "%s: dropped frame to %pM" 1763 " (unauthorized port)\n", dev->name, 1764 hdr.addr1); 1765 #endif 1766 1767 I802_DEBUG_INC(local->tx_handlers_drop_unauth_port); 1768 1769 ret = 0; 1770 goto fail; 1771 } 1772 1773 hdr.frame_control = fc; 1774 hdr.duration_id = 0; 1775 hdr.seq_ctrl = 0; 1776 1777 skip_header_bytes = ETH_HLEN; 1778 if (ethertype == ETH_P_AARP || ethertype == ETH_P_IPX) { 1779 encaps_data = bridge_tunnel_header; 1780 encaps_len = sizeof(bridge_tunnel_header); 1781 skip_header_bytes -= 2; 1782 } else if (ethertype >= 0x600) { 1783 encaps_data = rfc1042_header; 1784 encaps_len = sizeof(rfc1042_header); 1785 skip_header_bytes -= 2; 1786 } else { 1787 encaps_data = NULL; 1788 encaps_len = 0; 1789 } 1790 1791 skb_pull(skb, skip_header_bytes); 1792 nh_pos -= skip_header_bytes; 1793 h_pos -= skip_header_bytes; 1794 1795 head_need = hdrlen + encaps_len + meshhdrlen - skb_headroom(skb); 1796 1797 /* 1798 * So we need to modify the skb header and hence need a copy of 1799 * that. The head_need variable above doesn't, so far, include 1800 * the needed header space that we don't need right away. If we 1801 * can, then we don't reallocate right now but only after the 1802 * frame arrives at the master device (if it does...) 1803 * 1804 * If we cannot, however, then we will reallocate to include all 1805 * the ever needed space. Also, if we need to reallocate it anyway, 1806 * make it big enough for everything we may ever need. 1807 */ 1808 1809 if (head_need > 0 || skb_cloned(skb)) { 1810 head_need += IEEE80211_ENCRYPT_HEADROOM; 1811 head_need += local->tx_headroom; 1812 head_need = max_t(int, 0, head_need); 1813 if (ieee80211_skb_resize(local, skb, head_need, true)) 1814 goto fail; 1815 } 1816 1817 if (encaps_data) { 1818 memcpy(skb_push(skb, encaps_len), encaps_data, encaps_len); 1819 nh_pos += encaps_len; 1820 h_pos += encaps_len; 1821 } 1822 1823 if (meshhdrlen > 0) { 1824 memcpy(skb_push(skb, meshhdrlen), &mesh_hdr, meshhdrlen); 1825 nh_pos += meshhdrlen; 1826 h_pos += meshhdrlen; 1827 } 1828 1829 if (ieee80211_is_data_qos(fc)) { 1830 __le16 *qos_control; 1831 1832 qos_control = (__le16*) skb_push(skb, 2); 1833 memcpy(skb_push(skb, hdrlen - 2), &hdr, hdrlen - 2); 1834 /* 1835 * Maybe we could actually set some fields here, for now just 1836 * initialise to zero to indicate no special operation. 1837 */ 1838 *qos_control = 0; 1839 } else 1840 memcpy(skb_push(skb, hdrlen), &hdr, hdrlen); 1841 1842 nh_pos += hdrlen; 1843 h_pos += hdrlen; 1844 1845 skb->iif = dev->ifindex; 1846 1847 skb->dev = local->mdev; 1848 dev->stats.tx_packets++; 1849 dev->stats.tx_bytes += skb->len; 1850 1851 /* Update skb pointers to various headers since this modified frame 1852 * is going to go through Linux networking code that may potentially 1853 * need things like pointer to IP header. */ 1854 skb_set_mac_header(skb, 0); 1855 skb_set_network_header(skb, nh_pos); 1856 skb_set_transport_header(skb, h_pos); 1857 1858 dev->trans_start = jiffies; 1859 dev_queue_xmit(skb); 1860 1861 return 0; 1862 1863 fail: 1864 if (!ret) 1865 dev_kfree_skb(skb); 1866 1867 return ret; 1868 } 1869 1870 1871 /* 1872 * ieee80211_clear_tx_pending may not be called in a context where 1873 * it is possible that it packets could come in again. 1874 */ 1875 void ieee80211_clear_tx_pending(struct ieee80211_local *local) 1876 { 1877 int i; 1878 1879 for (i = 0; i < local->hw.queues; i++) 1880 skb_queue_purge(&local->pending[i]); 1881 } 1882 1883 static bool ieee80211_tx_pending_skb(struct ieee80211_local *local, 1884 struct sk_buff *skb) 1885 { 1886 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 1887 struct ieee80211_sub_if_data *sdata; 1888 struct sta_info *sta; 1889 struct ieee80211_hdr *hdr; 1890 struct net_device *dev; 1891 int ret; 1892 bool result = true; 1893 1894 /* does interface still exist? */ 1895 dev = dev_get_by_index(&init_net, skb->iif); 1896 if (!dev) { 1897 dev_kfree_skb(skb); 1898 return true; 1899 } 1900 1901 /* validate info->control.vif against skb->iif */ 1902 sdata = IEEE80211_DEV_TO_SUB_IF(dev); 1903 if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) 1904 sdata = container_of(sdata->bss, 1905 struct ieee80211_sub_if_data, 1906 u.ap); 1907 1908 if (unlikely(info->control.vif && info->control.vif != &sdata->vif)) { 1909 dev_kfree_skb(skb); 1910 result = true; 1911 goto out; 1912 } 1913 1914 if (info->flags & IEEE80211_TX_INTFL_NEED_TXPROCESSING) { 1915 ieee80211_tx(dev, skb, true); 1916 } else { 1917 hdr = (struct ieee80211_hdr *)skb->data; 1918 sta = sta_info_get(local, hdr->addr1); 1919 1920 ret = __ieee80211_tx(local, &skb, sta); 1921 if (ret != IEEE80211_TX_OK) 1922 result = false; 1923 } 1924 1925 out: 1926 dev_put(dev); 1927 1928 return result; 1929 } 1930 1931 /* 1932 * Transmit all pending packets. Called from tasklet, locks master device 1933 * TX lock so that no new packets can come in. 1934 */ 1935 void ieee80211_tx_pending(unsigned long data) 1936 { 1937 struct ieee80211_local *local = (struct ieee80211_local *)data; 1938 struct net_device *dev = local->mdev; 1939 unsigned long flags; 1940 int i; 1941 bool next; 1942 1943 rcu_read_lock(); 1944 netif_tx_lock_bh(dev); 1945 1946 for (i = 0; i < local->hw.queues; i++) { 1947 /* 1948 * If queue is stopped by something other than due to pending 1949 * frames, or we have no pending frames, proceed to next queue. 1950 */ 1951 spin_lock_irqsave(&local->queue_stop_reason_lock, flags); 1952 next = false; 1953 if (local->queue_stop_reasons[i] != 1954 BIT(IEEE80211_QUEUE_STOP_REASON_PENDING) || 1955 skb_queue_empty(&local->pending[i])) 1956 next = true; 1957 spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags); 1958 1959 if (next) 1960 continue; 1961 1962 /* 1963 * start the queue now to allow processing our packets, 1964 * we're under the tx lock here anyway so nothing will 1965 * happen as a result of this 1966 */ 1967 netif_start_subqueue(local->mdev, i); 1968 1969 while (!skb_queue_empty(&local->pending[i])) { 1970 struct sk_buff *skb = skb_dequeue(&local->pending[i]); 1971 1972 if (!ieee80211_tx_pending_skb(local, skb)) { 1973 skb_queue_head(&local->pending[i], skb); 1974 break; 1975 } 1976 } 1977 1978 /* Start regular packet processing again. */ 1979 if (skb_queue_empty(&local->pending[i])) 1980 ieee80211_wake_queue_by_reason(&local->hw, i, 1981 IEEE80211_QUEUE_STOP_REASON_PENDING); 1982 } 1983 1984 netif_tx_unlock_bh(dev); 1985 rcu_read_unlock(); 1986 } 1987 1988 /* functions for drivers to get certain frames */ 1989 1990 static void ieee80211_beacon_add_tim(struct ieee80211_if_ap *bss, 1991 struct sk_buff *skb, 1992 struct beacon_data *beacon) 1993 { 1994 u8 *pos, *tim; 1995 int aid0 = 0; 1996 int i, have_bits = 0, n1, n2; 1997 1998 /* Generate bitmap for TIM only if there are any STAs in power save 1999 * mode. */ 2000 if (atomic_read(&bss->num_sta_ps) > 0) 2001 /* in the hope that this is faster than 2002 * checking byte-for-byte */ 2003 have_bits = !bitmap_empty((unsigned long*)bss->tim, 2004 IEEE80211_MAX_AID+1); 2005 2006 if (bss->dtim_count == 0) 2007 bss->dtim_count = beacon->dtim_period - 1; 2008 else 2009 bss->dtim_count--; 2010 2011 tim = pos = (u8 *) skb_put(skb, 6); 2012 *pos++ = WLAN_EID_TIM; 2013 *pos++ = 4; 2014 *pos++ = bss->dtim_count; 2015 *pos++ = beacon->dtim_period; 2016 2017 if (bss->dtim_count == 0 && !skb_queue_empty(&bss->ps_bc_buf)) 2018 aid0 = 1; 2019 2020 if (have_bits) { 2021 /* Find largest even number N1 so that bits numbered 1 through 2022 * (N1 x 8) - 1 in the bitmap are 0 and number N2 so that bits 2023 * (N2 + 1) x 8 through 2007 are 0. */ 2024 n1 = 0; 2025 for (i = 0; i < IEEE80211_MAX_TIM_LEN; i++) { 2026 if (bss->tim[i]) { 2027 n1 = i & 0xfe; 2028 break; 2029 } 2030 } 2031 n2 = n1; 2032 for (i = IEEE80211_MAX_TIM_LEN - 1; i >= n1; i--) { 2033 if (bss->tim[i]) { 2034 n2 = i; 2035 break; 2036 } 2037 } 2038 2039 /* Bitmap control */ 2040 *pos++ = n1 | aid0; 2041 /* Part Virt Bitmap */ 2042 memcpy(pos, bss->tim + n1, n2 - n1 + 1); 2043 2044 tim[1] = n2 - n1 + 4; 2045 skb_put(skb, n2 - n1); 2046 } else { 2047 *pos++ = aid0; /* Bitmap control */ 2048 *pos++ = 0; /* Part Virt Bitmap */ 2049 } 2050 } 2051 2052 struct sk_buff *ieee80211_beacon_get(struct ieee80211_hw *hw, 2053 struct ieee80211_vif *vif) 2054 { 2055 struct ieee80211_local *local = hw_to_local(hw); 2056 struct sk_buff *skb = NULL; 2057 struct ieee80211_tx_info *info; 2058 struct ieee80211_sub_if_data *sdata = NULL; 2059 struct ieee80211_if_ap *ap = NULL; 2060 struct beacon_data *beacon; 2061 struct ieee80211_supported_band *sband; 2062 enum ieee80211_band band = local->hw.conf.channel->band; 2063 2064 sband = local->hw.wiphy->bands[band]; 2065 2066 rcu_read_lock(); 2067 2068 sdata = vif_to_sdata(vif); 2069 2070 if (sdata->vif.type == NL80211_IFTYPE_AP) { 2071 ap = &sdata->u.ap; 2072 beacon = rcu_dereference(ap->beacon); 2073 if (ap && beacon) { 2074 /* 2075 * headroom, head length, 2076 * tail length and maximum TIM length 2077 */ 2078 skb = dev_alloc_skb(local->tx_headroom + 2079 beacon->head_len + 2080 beacon->tail_len + 256); 2081 if (!skb) 2082 goto out; 2083 2084 skb_reserve(skb, local->tx_headroom); 2085 memcpy(skb_put(skb, beacon->head_len), beacon->head, 2086 beacon->head_len); 2087 2088 /* 2089 * Not very nice, but we want to allow the driver to call 2090 * ieee80211_beacon_get() as a response to the set_tim() 2091 * callback. That, however, is already invoked under the 2092 * sta_lock to guarantee consistent and race-free update 2093 * of the tim bitmap in mac80211 and the driver. 2094 */ 2095 if (local->tim_in_locked_section) { 2096 ieee80211_beacon_add_tim(ap, skb, beacon); 2097 } else { 2098 unsigned long flags; 2099 2100 spin_lock_irqsave(&local->sta_lock, flags); 2101 ieee80211_beacon_add_tim(ap, skb, beacon); 2102 spin_unlock_irqrestore(&local->sta_lock, flags); 2103 } 2104 2105 if (beacon->tail) 2106 memcpy(skb_put(skb, beacon->tail_len), 2107 beacon->tail, beacon->tail_len); 2108 } else 2109 goto out; 2110 } else if (sdata->vif.type == NL80211_IFTYPE_ADHOC) { 2111 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 2112 struct ieee80211_hdr *hdr; 2113 struct sk_buff *presp = rcu_dereference(ifibss->presp); 2114 2115 if (!presp) 2116 goto out; 2117 2118 skb = skb_copy(presp, GFP_ATOMIC); 2119 if (!skb) 2120 goto out; 2121 2122 hdr = (struct ieee80211_hdr *) skb->data; 2123 hdr->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 2124 IEEE80211_STYPE_BEACON); 2125 } else if (ieee80211_vif_is_mesh(&sdata->vif)) { 2126 struct ieee80211_mgmt *mgmt; 2127 u8 *pos; 2128 2129 /* headroom, head length, tail length and maximum TIM length */ 2130 skb = dev_alloc_skb(local->tx_headroom + 400); 2131 if (!skb) 2132 goto out; 2133 2134 skb_reserve(skb, local->hw.extra_tx_headroom); 2135 mgmt = (struct ieee80211_mgmt *) 2136 skb_put(skb, 24 + sizeof(mgmt->u.beacon)); 2137 memset(mgmt, 0, 24 + sizeof(mgmt->u.beacon)); 2138 mgmt->frame_control = 2139 cpu_to_le16(IEEE80211_FTYPE_MGMT | IEEE80211_STYPE_BEACON); 2140 memset(mgmt->da, 0xff, ETH_ALEN); 2141 memcpy(mgmt->sa, sdata->dev->dev_addr, ETH_ALEN); 2142 /* BSSID is left zeroed, wildcard value */ 2143 mgmt->u.beacon.beacon_int = 2144 cpu_to_le16(sdata->vif.bss_conf.beacon_int); 2145 mgmt->u.beacon.capab_info = 0x0; /* 0x0 for MPs */ 2146 2147 pos = skb_put(skb, 2); 2148 *pos++ = WLAN_EID_SSID; 2149 *pos++ = 0x0; 2150 2151 mesh_mgmt_ies_add(skb, sdata); 2152 } else { 2153 WARN_ON(1); 2154 goto out; 2155 } 2156 2157 info = IEEE80211_SKB_CB(skb); 2158 2159 skb->do_not_encrypt = 1; 2160 2161 info->band = band; 2162 /* 2163 * XXX: For now, always use the lowest rate 2164 */ 2165 info->control.rates[0].idx = 0; 2166 info->control.rates[0].count = 1; 2167 info->control.rates[1].idx = -1; 2168 info->control.rates[2].idx = -1; 2169 info->control.rates[3].idx = -1; 2170 info->control.rates[4].idx = -1; 2171 BUILD_BUG_ON(IEEE80211_TX_MAX_RATES != 5); 2172 2173 info->control.vif = vif; 2174 2175 info->flags |= IEEE80211_TX_CTL_NO_ACK; 2176 info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT; 2177 info->flags |= IEEE80211_TX_CTL_ASSIGN_SEQ; 2178 out: 2179 rcu_read_unlock(); 2180 return skb; 2181 } 2182 EXPORT_SYMBOL(ieee80211_beacon_get); 2183 2184 void ieee80211_rts_get(struct ieee80211_hw *hw, struct ieee80211_vif *vif, 2185 const void *frame, size_t frame_len, 2186 const struct ieee80211_tx_info *frame_txctl, 2187 struct ieee80211_rts *rts) 2188 { 2189 const struct ieee80211_hdr *hdr = frame; 2190 2191 rts->frame_control = 2192 cpu_to_le16(IEEE80211_FTYPE_CTL | IEEE80211_STYPE_RTS); 2193 rts->duration = ieee80211_rts_duration(hw, vif, frame_len, 2194 frame_txctl); 2195 memcpy(rts->ra, hdr->addr1, sizeof(rts->ra)); 2196 memcpy(rts->ta, hdr->addr2, sizeof(rts->ta)); 2197 } 2198 EXPORT_SYMBOL(ieee80211_rts_get); 2199 2200 void ieee80211_ctstoself_get(struct ieee80211_hw *hw, struct ieee80211_vif *vif, 2201 const void *frame, size_t frame_len, 2202 const struct ieee80211_tx_info *frame_txctl, 2203 struct ieee80211_cts *cts) 2204 { 2205 const struct ieee80211_hdr *hdr = frame; 2206 2207 cts->frame_control = 2208 cpu_to_le16(IEEE80211_FTYPE_CTL | IEEE80211_STYPE_CTS); 2209 cts->duration = ieee80211_ctstoself_duration(hw, vif, 2210 frame_len, frame_txctl); 2211 memcpy(cts->ra, hdr->addr1, sizeof(cts->ra)); 2212 } 2213 EXPORT_SYMBOL(ieee80211_ctstoself_get); 2214 2215 struct sk_buff * 2216 ieee80211_get_buffered_bc(struct ieee80211_hw *hw, 2217 struct ieee80211_vif *vif) 2218 { 2219 struct ieee80211_local *local = hw_to_local(hw); 2220 struct sk_buff *skb = NULL; 2221 struct sta_info *sta; 2222 struct ieee80211_tx_data tx; 2223 struct ieee80211_sub_if_data *sdata; 2224 struct ieee80211_if_ap *bss = NULL; 2225 struct beacon_data *beacon; 2226 struct ieee80211_tx_info *info; 2227 2228 sdata = vif_to_sdata(vif); 2229 bss = &sdata->u.ap; 2230 2231 if (!bss) 2232 return NULL; 2233 2234 rcu_read_lock(); 2235 beacon = rcu_dereference(bss->beacon); 2236 2237 if (sdata->vif.type != NL80211_IFTYPE_AP || !beacon || !beacon->head) 2238 goto out; 2239 2240 if (bss->dtim_count != 0) 2241 goto out; /* send buffered bc/mc only after DTIM beacon */ 2242 2243 while (1) { 2244 skb = skb_dequeue(&bss->ps_bc_buf); 2245 if (!skb) 2246 goto out; 2247 local->total_ps_buffered--; 2248 2249 if (!skb_queue_empty(&bss->ps_bc_buf) && skb->len >= 2) { 2250 struct ieee80211_hdr *hdr = 2251 (struct ieee80211_hdr *) skb->data; 2252 /* more buffered multicast/broadcast frames ==> set 2253 * MoreData flag in IEEE 802.11 header to inform PS 2254 * STAs */ 2255 hdr->frame_control |= 2256 cpu_to_le16(IEEE80211_FCTL_MOREDATA); 2257 } 2258 2259 if (!ieee80211_tx_prepare(local, &tx, skb)) 2260 break; 2261 dev_kfree_skb_any(skb); 2262 } 2263 2264 info = IEEE80211_SKB_CB(skb); 2265 2266 sta = tx.sta; 2267 tx.flags |= IEEE80211_TX_PS_BUFFERED; 2268 tx.channel = local->hw.conf.channel; 2269 info->band = tx.channel->band; 2270 2271 if (invoke_tx_handlers(&tx)) 2272 skb = NULL; 2273 out: 2274 rcu_read_unlock(); 2275 2276 return skb; 2277 } 2278 EXPORT_SYMBOL(ieee80211_get_buffered_bc); 2279