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>
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.
12 * Transmit and frame generation functions.
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>
27 #include "ieee80211_i.h"
28 #include "driver-ops.h"
36 #define IEEE80211_TX_OK 0
37 #define IEEE80211_TX_AGAIN 1
38 #define IEEE80211_TX_PENDING 2
42 static __le16 ieee80211_duration(struct ieee80211_tx_data *tx, int group_addr,
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);
52 /* assume HW handles this */
53 if (info->control.rates[0].flags & IEEE80211_TX_RC_MCS)
57 if (WARN_ON_ONCE(info->control.rates[0].idx < 0))
60 sband = local->hw.wiphy->bands[tx->channel->band];
61 txrate = &sband->bitrates[info->control.rates[0].idx];
63 erp = txrate->flags & IEEE80211_RATE_ERP_G;
66 * data and mgmt (except PS Poll):
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
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
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.
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
96 * PS Poll: BIT(15) | BIT(14) | aid
102 if (0 /* FIX: data/mgmt during CFP */)
103 return cpu_to_le16(32768);
105 if (group_addr) /* Group address as the destination - no ACK */
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
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];
124 if (r->bitrate > txrate->bitrate)
127 if (tx->sdata->vif.bss_conf.basic_rates & BIT(i))
130 switch (sband->band) {
131 case IEEE80211_BAND_2GHZ: {
133 if (tx->sdata->flags & IEEE80211_SDATA_OPERATING_GMODE)
134 flag = IEEE80211_RATE_MANDATORY_G;
136 flag = IEEE80211_RATE_MANDATORY_B;
141 case IEEE80211_BAND_5GHZ:
142 if (r->flags & IEEE80211_RATE_MANDATORY_A)
145 case IEEE80211_NUM_BANDS:
151 /* No matching basic rate found; use highest suitable mandatory
156 /* Time needed to transmit ACK
157 * (10 bytes + 4-byte FCS = 112 bits) plus SIFS; rounded up
158 * to closest integer */
160 dur = ieee80211_frame_duration(local, 10, rate, erp,
161 tx->sdata->vif.bss_conf.use_short_preamble);
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 */
168 dur += ieee80211_frame_duration(local, next_frag_len,
169 txrate->bitrate, erp,
170 tx->sdata->vif.bss_conf.use_short_preamble);
173 return cpu_to_le16(dur);
176 static int inline is_ieee80211_device(struct ieee80211_local *local,
177 struct net_device *dev)
179 return local == wdev_priv(dev->ieee80211_ptr);
184 static ieee80211_tx_result debug_noinline
185 ieee80211_tx_h_check_assoc(struct ieee80211_tx_data *tx)
188 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
189 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
192 if (unlikely(info->flags & IEEE80211_TX_CTL_INJECTED))
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))
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.
207 * http://article.gmane.org/gmane.linux.kernel.wireless.general/30089
211 if (tx->sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
214 if (tx->flags & IEEE80211_TX_PS_BUFFERED)
217 sta_flags = tx->sta ? get_sta_flags(tx->sta) : 0;
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);
232 if (unlikely(ieee80211_is_data(hdr->frame_control) &&
233 tx->local->num_sta == 0 &&
234 tx->sdata->vif.type != NL80211_IFTYPE_ADHOC)) {
236 * No associated STAs - no need to send multicast
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)
253 int total = 0, purged = 0;
255 struct ieee80211_sub_if_data *sdata;
256 struct sta_info *sta;
259 * virtual interfaces are protected by RCU
263 list_for_each_entry_rcu(sdata, &local->interfaces, list) {
264 struct ieee80211_if_ap *ap;
265 if (sdata->vif.type != NL80211_IFTYPE_AP)
268 skb = skb_dequeue(&ap->ps_bc_buf);
273 total += skb_queue_len(&ap->ps_bc_buf);
276 list_for_each_entry_rcu(sta, &local->sta_list, list) {
277 skb = skb_dequeue(&sta->ps_tx_buf);
282 total += skb_queue_len(&sta->ps_tx_buf);
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);
294 static ieee80211_tx_result
295 ieee80211_tx_h_multicast_ps_buf(struct ieee80211_tx_data *tx)
297 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
298 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
301 * broadcast/multicast frame
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.
308 /* powersaving STAs only in AP/VLAN mode */
312 /* no buffering for ordered frames */
313 if (ieee80211_has_order(hdr->frame_control))
316 /* no stations in PS mode */
317 if (!atomic_read(&tx->sdata->bss->num_sta_ps))
320 info->flags |= IEEE80211_TX_CTL_SEND_AFTER_DTIM;
322 /* device releases frame after DTIM beacon */
323 if (!(tx->local->hw.flags & IEEE80211_HW_HOST_BROADCAST_PS_BUFFERING))
326 /* buffered in mac80211 */
327 if (tx->local->total_ps_buffered >= TOTAL_MAX_TX_BUFFER)
328 purge_old_ps_buffers(tx->local);
330 if (skb_queue_len(&tx->sdata->bss->ps_bc_buf) >= AP_MAX_BC_BUFFER) {
331 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
333 printk(KERN_DEBUG "%s: BC TX buffer full - dropping the oldest frame\n",
336 dev_kfree_skb(skb_dequeue(&tx->sdata->bss->ps_bc_buf));
338 tx->local->total_ps_buffered++;
340 skb_queue_tail(&tx->sdata->bss->ps_bc_buf, tx->skb);
345 static int ieee80211_use_mfp(__le16 fc, struct sta_info *sta,
348 if (!ieee80211_is_mgmt(fc))
351 if (sta == NULL || !test_sta_flags(sta, WLAN_STA_MFP))
354 if (!ieee80211_is_robust_mgmt_frame((struct ieee80211_hdr *)
361 static ieee80211_tx_result
362 ieee80211_tx_h_unicast_ps_buf(struct ieee80211_tx_data *tx)
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;
369 if (unlikely(!sta || ieee80211_is_probe_resp(hdr->frame_control)
370 || ieee80211_is_auth(hdr->frame_control)
371 || ieee80211_is_assoc_resp(hdr->frame_control)
372 || ieee80211_is_reassoc_resp(hdr->frame_control)))
375 staflags = get_sta_flags(sta);
377 if (unlikely((staflags & WLAN_STA_PS) &&
378 !(info->flags & IEEE80211_TX_CTL_PSPOLL_RESPONSE))) {
379 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
380 printk(KERN_DEBUG "STA %pM aid %d: PS buffer (entries "
382 sta->sta.addr, sta->sta.aid,
383 skb_queue_len(&sta->ps_tx_buf));
384 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
385 if (tx->local->total_ps_buffered >= TOTAL_MAX_TX_BUFFER)
386 purge_old_ps_buffers(tx->local);
387 if (skb_queue_len(&sta->ps_tx_buf) >= STA_MAX_TX_BUFFER) {
388 struct sk_buff *old = skb_dequeue(&sta->ps_tx_buf);
389 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
390 if (net_ratelimit()) {
391 printk(KERN_DEBUG "%s: STA %pM TX "
392 "buffer full - dropping oldest frame\n",
393 tx->dev->name, sta->sta.addr);
398 tx->local->total_ps_buffered++;
400 /* Queue frame to be sent after STA sends an PS Poll frame */
401 if (skb_queue_empty(&sta->ps_tx_buf))
402 sta_info_set_tim_bit(sta);
404 info->control.jiffies = jiffies;
405 info->control.vif = &tx->sdata->vif;
406 info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
407 skb_queue_tail(&sta->ps_tx_buf, tx->skb);
410 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
411 else if (unlikely(test_sta_flags(sta, WLAN_STA_PS))) {
412 printk(KERN_DEBUG "%s: STA %pM in PS mode, but pspoll "
413 "set -> send frame\n", tx->dev->name,
416 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
421 static ieee80211_tx_result debug_noinline
422 ieee80211_tx_h_ps_buf(struct ieee80211_tx_data *tx)
424 if (unlikely(tx->flags & IEEE80211_TX_PS_BUFFERED))
427 if (tx->flags & IEEE80211_TX_UNICAST)
428 return ieee80211_tx_h_unicast_ps_buf(tx);
430 return ieee80211_tx_h_multicast_ps_buf(tx);
433 static ieee80211_tx_result debug_noinline
434 ieee80211_tx_h_select_key(struct ieee80211_tx_data *tx)
436 struct ieee80211_key *key = NULL;
437 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
438 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
440 if (unlikely(info->flags & IEEE80211_TX_INTFL_DONT_ENCRYPT))
442 else if (tx->sta && (key = rcu_dereference(tx->sta->key)))
444 else if (ieee80211_is_mgmt(hdr->frame_control) &&
445 (key = rcu_dereference(tx->sdata->default_mgmt_key)))
447 else if ((key = rcu_dereference(tx->sdata->default_key)))
449 else if (tx->sdata->drop_unencrypted &&
450 (tx->skb->protocol != cpu_to_be16(ETH_P_PAE)) &&
451 !(info->flags & IEEE80211_TX_CTL_INJECTED) &&
452 (!ieee80211_is_robust_mgmt_frame(hdr) ||
453 (ieee80211_is_action(hdr->frame_control) &&
454 tx->sta && test_sta_flags(tx->sta, WLAN_STA_MFP)))) {
455 I802_DEBUG_INC(tx->local->tx_handlers_drop_unencrypted);
461 tx->key->tx_rx_count++;
462 /* TODO: add threshold stuff again */
464 switch (tx->key->conf.alg) {
466 if (ieee80211_is_auth(hdr->frame_control))
469 if (!ieee80211_is_data_present(hdr->frame_control))
473 if (!ieee80211_is_data_present(hdr->frame_control) &&
474 !ieee80211_use_mfp(hdr->frame_control, tx->sta,
479 if (!ieee80211_is_mgmt(hdr->frame_control))
485 if (!tx->key || !(tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))
486 info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
491 static ieee80211_tx_result debug_noinline
492 ieee80211_tx_h_rate_ctrl(struct ieee80211_tx_data *tx)
494 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
495 struct ieee80211_hdr *hdr = (void *)tx->skb->data;
496 struct ieee80211_supported_band *sband;
497 struct ieee80211_rate *rate;
499 bool inval = false, rts = false, short_preamble = false;
500 struct ieee80211_tx_rate_control txrc;
503 memset(&txrc, 0, sizeof(txrc));
505 sband = tx->local->hw.wiphy->bands[tx->channel->band];
507 len = min_t(int, tx->skb->len + FCS_LEN,
508 tx->local->hw.wiphy->frag_threshold);
510 /* set up the tx rate control struct we give the RC algo */
511 txrc.hw = local_to_hw(tx->local);
513 txrc.bss_conf = &tx->sdata->vif.bss_conf;
515 txrc.reported_rate.idx = -1;
516 txrc.max_rate_idx = tx->sdata->max_ratectrl_rateidx;
518 /* set up RTS protection if desired */
519 if (len > tx->local->hw.wiphy->rts_threshold) {
520 txrc.rts = rts = true;
524 * Use short preamble if the BSS can handle it, but not for
525 * management frames unless we know the receiver can handle
526 * that -- the management frame might be to a station that
527 * just wants a probe response.
529 if (tx->sdata->vif.bss_conf.use_short_preamble &&
530 (ieee80211_is_data(hdr->frame_control) ||
531 (tx->sta && test_sta_flags(tx->sta, WLAN_STA_SHORT_PREAMBLE))))
532 txrc.short_preamble = short_preamble = true;
534 sta_flags = tx->sta ? get_sta_flags(tx->sta) : 0;
537 * Lets not bother rate control if we're associated and cannot
538 * talk to the sta. This should not happen.
540 if (WARN(test_bit(SCAN_SW_SCANNING, &tx->local->scanning) &&
541 (sta_flags & WLAN_STA_ASSOC) &&
542 !rate_usable_index_exists(sband, &tx->sta->sta),
543 "%s: Dropped data frame as no usable bitrate found while "
544 "scanning and associated. Target station: "
545 "%pM on %d GHz band\n",
546 tx->dev->name, hdr->addr1,
547 tx->channel->band ? 5 : 2))
551 * If we're associated with the sta at this point we know we can at
552 * least send the frame at the lowest bit rate.
554 rate_control_get_rate(tx->sdata, tx->sta, &txrc);
556 if (unlikely(info->control.rates[0].idx < 0))
559 if (txrc.reported_rate.idx < 0)
560 txrc.reported_rate = info->control.rates[0];
563 tx->sta->last_tx_rate = txrc.reported_rate;
565 if (unlikely(!info->control.rates[0].count))
566 info->control.rates[0].count = 1;
568 if (WARN_ON_ONCE((info->control.rates[0].count > 1) &&
569 (info->flags & IEEE80211_TX_CTL_NO_ACK)))
570 info->control.rates[0].count = 1;
572 if (is_multicast_ether_addr(hdr->addr1)) {
574 * XXX: verify the rate is in the basic rateset
580 * set up the RTS/CTS rate as the fastest basic rate
581 * that is not faster than the data rate
583 * XXX: Should this check all retry rates?
585 if (!(info->control.rates[0].flags & IEEE80211_TX_RC_MCS)) {
588 rate = &sband->bitrates[info->control.rates[0].idx];
590 for (i = 0; i < sband->n_bitrates; i++) {
591 /* must be a basic rate */
592 if (!(tx->sdata->vif.bss_conf.basic_rates & BIT(i)))
594 /* must not be faster than the data rate */
595 if (sband->bitrates[i].bitrate > rate->bitrate)
598 if (sband->bitrates[baserate].bitrate <
599 sband->bitrates[i].bitrate)
603 info->control.rts_cts_rate_idx = baserate;
606 for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) {
608 * make sure there's no valid rate following
609 * an invalid one, just in case drivers don't
610 * take the API seriously to stop at -1.
613 info->control.rates[i].idx = -1;
616 if (info->control.rates[i].idx < 0) {
622 * For now assume MCS is already set up correctly, this
625 if (info->control.rates[i].flags & IEEE80211_TX_RC_MCS) {
626 WARN_ON(info->control.rates[i].idx > 76);
630 /* set up RTS protection if desired */
632 info->control.rates[i].flags |=
633 IEEE80211_TX_RC_USE_RTS_CTS;
636 if (WARN_ON_ONCE(info->control.rates[i].idx >=
637 sband->n_bitrates)) {
638 info->control.rates[i].idx = -1;
642 rate = &sband->bitrates[info->control.rates[i].idx];
644 /* set up short preamble */
645 if (short_preamble &&
646 rate->flags & IEEE80211_RATE_SHORT_PREAMBLE)
647 info->control.rates[i].flags |=
648 IEEE80211_TX_RC_USE_SHORT_PREAMBLE;
650 /* set up G protection */
651 if (!rts && tx->sdata->vif.bss_conf.use_cts_prot &&
652 rate->flags & IEEE80211_RATE_ERP_G)
653 info->control.rates[i].flags |=
654 IEEE80211_TX_RC_USE_CTS_PROTECT;
660 static ieee80211_tx_result debug_noinline
661 ieee80211_tx_h_misc(struct ieee80211_tx_data *tx)
663 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
666 info->control.sta = &tx->sta->sta;
671 static ieee80211_tx_result debug_noinline
672 ieee80211_tx_h_sequence(struct ieee80211_tx_data *tx)
674 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
675 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
681 * Packet injection may want to control the sequence
682 * number, if we have no matching interface then we
683 * neither assign one ourselves nor ask the driver to.
685 if (unlikely(info->control.vif->type == NL80211_IFTYPE_MONITOR))
688 if (unlikely(ieee80211_is_ctl(hdr->frame_control)))
691 if (ieee80211_hdrlen(hdr->frame_control) < 24)
695 * Anything but QoS data that has a sequence number field
696 * (is long enough) gets a sequence number from the global
699 if (!ieee80211_is_data_qos(hdr->frame_control)) {
700 /* driver should assign sequence number */
701 info->flags |= IEEE80211_TX_CTL_ASSIGN_SEQ;
702 /* for pure STA mode without beacons, we can do it */
703 hdr->seq_ctrl = cpu_to_le16(tx->sdata->sequence_number);
704 tx->sdata->sequence_number += 0x10;
709 * This should be true for injected/management frames only, for
710 * management frames we have set the IEEE80211_TX_CTL_ASSIGN_SEQ
711 * above since they are not QoS-data frames.
716 /* include per-STA, per-TID sequence counter */
718 qc = ieee80211_get_qos_ctl(hdr);
719 tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
720 seq = &tx->sta->tid_seq[tid];
722 hdr->seq_ctrl = cpu_to_le16(*seq);
724 /* Increase the sequence number. */
725 *seq = (*seq + 0x10) & IEEE80211_SCTL_SEQ;
730 static int ieee80211_fragment(struct ieee80211_local *local,
731 struct sk_buff *skb, int hdrlen,
734 struct sk_buff *tail = skb, *tmp;
735 int per_fragm = frag_threshold - hdrlen - FCS_LEN;
736 int pos = hdrlen + per_fragm;
737 int rem = skb->len - hdrlen - per_fragm;
739 if (WARN_ON(rem < 0))
743 int fraglen = per_fragm;
748 tmp = dev_alloc_skb(local->tx_headroom +
750 IEEE80211_ENCRYPT_HEADROOM +
751 IEEE80211_ENCRYPT_TAILROOM);
756 skb_reserve(tmp, local->tx_headroom +
757 IEEE80211_ENCRYPT_HEADROOM);
758 /* copy control information */
759 memcpy(tmp->cb, skb->cb, sizeof(tmp->cb));
760 skb_copy_queue_mapping(tmp, skb);
761 tmp->priority = skb->priority;
764 /* copy header and data */
765 memcpy(skb_put(tmp, hdrlen), skb->data, hdrlen);
766 memcpy(skb_put(tmp, fraglen), skb->data + pos, fraglen);
771 skb->len = hdrlen + per_fragm;
775 static ieee80211_tx_result debug_noinline
776 ieee80211_tx_h_fragment(struct ieee80211_tx_data *tx)
778 struct sk_buff *skb = tx->skb;
779 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
780 struct ieee80211_hdr *hdr = (void *)skb->data;
781 int frag_threshold = tx->local->hw.wiphy->frag_threshold;
785 if (!(tx->flags & IEEE80211_TX_FRAGMENTED))
789 * Warn when submitting a fragmented A-MPDU frame and drop it.
790 * This scenario is handled in ieee80211_tx_prepare but extra
791 * caution taken here as fragmented ampdu may cause Tx stop.
793 if (WARN_ON(info->flags & IEEE80211_TX_CTL_AMPDU))
796 hdrlen = ieee80211_hdrlen(hdr->frame_control);
798 /* internal error, why is TX_FRAGMENTED set? */
799 if (WARN_ON(skb->len + FCS_LEN <= frag_threshold))
803 * Now fragment the frame. This will allocate all the fragments and
804 * chain them (using skb as the first fragment) to skb->next.
805 * During transmission, we will remove the successfully transmitted
806 * fragments from this list. When the low-level driver rejects one
807 * of the fragments then we will simply pretend to accept the skb
808 * but store it away as pending.
810 if (ieee80211_fragment(tx->local, skb, hdrlen, frag_threshold))
813 /* update duration/seq/flags of fragments */
817 const __le16 morefrags = cpu_to_le16(IEEE80211_FCTL_MOREFRAGS);
819 hdr = (void *)skb->data;
820 info = IEEE80211_SKB_CB(skb);
823 hdr->frame_control |= morefrags;
824 next_len = skb->next->len;
826 * No multi-rate retries for fragmented frames, that
827 * would completely throw off the NAV at other STAs.
829 info->control.rates[1].idx = -1;
830 info->control.rates[2].idx = -1;
831 info->control.rates[3].idx = -1;
832 info->control.rates[4].idx = -1;
833 BUILD_BUG_ON(IEEE80211_TX_MAX_RATES != 5);
834 info->flags &= ~IEEE80211_TX_CTL_RATE_CTRL_PROBE;
836 hdr->frame_control &= ~morefrags;
839 hdr->duration_id = ieee80211_duration(tx, 0, next_len);
840 hdr->seq_ctrl |= cpu_to_le16(fragnum & IEEE80211_SCTL_FRAG);
842 } while ((skb = skb->next));
847 static ieee80211_tx_result debug_noinline
848 ieee80211_tx_h_stats(struct ieee80211_tx_data *tx)
850 struct sk_buff *skb = tx->skb;
855 tx->sta->tx_packets++;
857 tx->sta->tx_fragments++;
858 tx->sta->tx_bytes += skb->len;
859 } while ((skb = skb->next));
864 static ieee80211_tx_result debug_noinline
865 ieee80211_tx_h_encrypt(struct ieee80211_tx_data *tx)
870 switch (tx->key->conf.alg) {
872 return ieee80211_crypto_wep_encrypt(tx);
874 return ieee80211_crypto_tkip_encrypt(tx);
876 return ieee80211_crypto_ccmp_encrypt(tx);
878 return ieee80211_crypto_aes_cmac_encrypt(tx);
886 static ieee80211_tx_result debug_noinline
887 ieee80211_tx_h_calculate_duration(struct ieee80211_tx_data *tx)
889 struct sk_buff *skb = tx->skb;
890 struct ieee80211_hdr *hdr;
895 hdr = (void *) skb->data;
896 if (unlikely(ieee80211_is_pspoll(hdr->frame_control)))
897 break; /* must not overwrite AID */
898 next_len = skb->next ? skb->next->len : 0;
899 group_addr = is_multicast_ether_addr(hdr->addr1);
902 ieee80211_duration(tx, group_addr, next_len);
903 } while ((skb = skb->next));
908 /* actual transmit path */
911 * deal with packet injection down monitor interface
912 * with Radiotap Header -- only called for monitor mode interface
914 static bool __ieee80211_parse_tx_radiotap(struct ieee80211_tx_data *tx,
918 * this is the moment to interpret and discard the radiotap header that
919 * must be at the start of the packet injected in Monitor mode
921 * Need to take some care with endian-ness since radiotap
922 * args are little-endian
925 struct ieee80211_radiotap_iterator iterator;
926 struct ieee80211_radiotap_header *rthdr =
927 (struct ieee80211_radiotap_header *) skb->data;
928 struct ieee80211_supported_band *sband;
929 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
930 int ret = ieee80211_radiotap_iterator_init(&iterator, rthdr, skb->len);
932 sband = tx->local->hw.wiphy->bands[tx->channel->band];
934 info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
935 tx->flags &= ~IEEE80211_TX_FRAGMENTED;
938 * for every radiotap entry that is present
939 * (ieee80211_radiotap_iterator_next returns -ENOENT when no more
940 * entries present, or -EINVAL on error)
944 ret = ieee80211_radiotap_iterator_next(&iterator);
949 /* see if this argument is something we can use */
950 switch (iterator.this_arg_index) {
952 * You must take care when dereferencing iterator.this_arg
953 * for multibyte types... the pointer is not aligned. Use
954 * get_unaligned((type *)iterator.this_arg) to dereference
955 * iterator.this_arg for type "type" safely on all arches.
957 case IEEE80211_RADIOTAP_FLAGS:
958 if (*iterator.this_arg & IEEE80211_RADIOTAP_F_FCS) {
960 * this indicates that the skb we have been
961 * handed has the 32-bit FCS CRC at the end...
962 * we should react to that by snipping it off
963 * because it will be recomputed and added
966 if (skb->len < (iterator.max_length + FCS_LEN))
969 skb_trim(skb, skb->len - FCS_LEN);
971 if (*iterator.this_arg & IEEE80211_RADIOTAP_F_WEP)
972 info->flags &= ~IEEE80211_TX_INTFL_DONT_ENCRYPT;
973 if (*iterator.this_arg & IEEE80211_RADIOTAP_F_FRAG)
974 tx->flags |= IEEE80211_TX_FRAGMENTED;
978 * Please update the file
979 * Documentation/networking/mac80211-injection.txt
980 * when parsing new fields here.
988 if (ret != -ENOENT) /* ie, if we didn't simply run out of fields */
992 * remove the radiotap header
993 * iterator->max_length was sanity-checked against
994 * skb->len by iterator init
996 skb_pull(skb, iterator.max_length);
1004 static ieee80211_tx_result
1005 ieee80211_tx_prepare(struct ieee80211_sub_if_data *sdata,
1006 struct ieee80211_tx_data *tx,
1007 struct sk_buff *skb)
1009 struct ieee80211_local *local = sdata->local;
1010 struct ieee80211_hdr *hdr;
1011 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1014 bool queued = false;
1016 memset(tx, 0, sizeof(*tx));
1018 tx->dev = sdata->dev; /* use original interface */
1021 tx->channel = local->hw.conf.channel;
1023 * Set this flag (used below to indicate "automatic fragmentation"),
1024 * it will be cleared/left by radiotap as desired.
1026 tx->flags |= IEEE80211_TX_FRAGMENTED;
1028 /* process and remove the injection radiotap header */
1029 if (unlikely(info->flags & IEEE80211_TX_CTL_INJECTED)) {
1030 if (!__ieee80211_parse_tx_radiotap(tx, skb))
1034 * __ieee80211_parse_tx_radiotap has now removed
1035 * the radiotap header that was present and pre-filled
1036 * 'tx' with tx control information.
1041 * If this flag is set to true anywhere, and we get here,
1042 * we are doing the needed processing, so remove the flag
1045 info->flags &= ~IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1047 hdr = (struct ieee80211_hdr *) skb->data;
1049 tx->sta = sta_info_get(local, hdr->addr1);
1051 if (tx->sta && ieee80211_is_data_qos(hdr->frame_control) &&
1052 (local->hw.flags & IEEE80211_HW_AMPDU_AGGREGATION)) {
1053 unsigned long flags;
1054 struct tid_ampdu_tx *tid_tx;
1056 qc = ieee80211_get_qos_ctl(hdr);
1057 tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
1059 spin_lock_irqsave(&tx->sta->lock, flags);
1061 * XXX: This spinlock could be fairly expensive, but see the
1062 * comment in agg-tx.c:ieee80211_agg_tx_operational().
1063 * One way to solve this would be to do something RCU-like
1064 * for managing the tid_tx struct and using atomic bitops
1065 * for the actual state -- by introducing an actual
1066 * 'operational' bit that would be possible. It would
1067 * require changing ieee80211_agg_tx_operational() to
1068 * set that bit, and changing the way tid_tx is managed
1069 * everywhere, including races between that bit and
1070 * tid_tx going away (tid_tx being added can be easily
1071 * committed to memory before the 'operational' bit).
1073 tid_tx = tx->sta->ampdu_mlme.tid_tx[tid];
1074 state = &tx->sta->ampdu_mlme.tid_state_tx[tid];
1075 if (*state == HT_AGG_STATE_OPERATIONAL) {
1076 info->flags |= IEEE80211_TX_CTL_AMPDU;
1077 } else if (*state != HT_AGG_STATE_IDLE) {
1080 info->control.vif = &sdata->vif;
1081 info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1082 __skb_queue_tail(&tid_tx->pending, skb);
1084 spin_unlock_irqrestore(&tx->sta->lock, flags);
1086 if (unlikely(queued))
1090 if (is_multicast_ether_addr(hdr->addr1)) {
1091 tx->flags &= ~IEEE80211_TX_UNICAST;
1092 info->flags |= IEEE80211_TX_CTL_NO_ACK;
1094 tx->flags |= IEEE80211_TX_UNICAST;
1095 if (unlikely(local->wifi_wme_noack_test))
1096 info->flags |= IEEE80211_TX_CTL_NO_ACK;
1098 info->flags &= ~IEEE80211_TX_CTL_NO_ACK;
1101 if (tx->flags & IEEE80211_TX_FRAGMENTED) {
1102 if ((tx->flags & IEEE80211_TX_UNICAST) &&
1103 skb->len + FCS_LEN > local->hw.wiphy->frag_threshold &&
1104 !(info->flags & IEEE80211_TX_CTL_AMPDU))
1105 tx->flags |= IEEE80211_TX_FRAGMENTED;
1107 tx->flags &= ~IEEE80211_TX_FRAGMENTED;
1111 info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT;
1112 else if (test_and_clear_sta_flags(tx->sta, WLAN_STA_CLEAR_PS_FILT))
1113 info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT;
1115 hdrlen = ieee80211_hdrlen(hdr->frame_control);
1116 if (skb->len > hdrlen + sizeof(rfc1042_header) + 2) {
1117 u8 *pos = &skb->data[hdrlen + sizeof(rfc1042_header)];
1118 tx->ethertype = (pos[0] << 8) | pos[1];
1120 info->flags |= IEEE80211_TX_CTL_FIRST_FRAGMENT;
1125 static int __ieee80211_tx(struct ieee80211_local *local,
1126 struct sk_buff **skbp,
1127 struct sta_info *sta,
1130 struct sk_buff *skb = *skbp, *next;
1131 struct ieee80211_tx_info *info;
1132 struct ieee80211_sub_if_data *sdata;
1133 unsigned long flags;
1138 int q = skb_get_queue_mapping(skb);
1140 spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
1141 ret = IEEE80211_TX_OK;
1142 if (local->queue_stop_reasons[q] ||
1143 (!txpending && !skb_queue_empty(&local->pending[q])))
1144 ret = IEEE80211_TX_PENDING;
1145 spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
1146 if (ret != IEEE80211_TX_OK)
1149 info = IEEE80211_SKB_CB(skb);
1152 info->flags &= ~(IEEE80211_TX_CTL_CLEAR_PS_FILT |
1153 IEEE80211_TX_CTL_FIRST_FRAGMENT);
1159 info->flags |= IEEE80211_TX_CTL_MORE_FRAMES;
1161 sdata = vif_to_sdata(info->control.vif);
1163 switch (sdata->vif.type) {
1164 case NL80211_IFTYPE_MONITOR:
1165 info->control.vif = NULL;
1167 case NL80211_IFTYPE_AP_VLAN:
1168 info->control.vif = &container_of(sdata->bss,
1169 struct ieee80211_sub_if_data, u.ap)->vif;
1176 ret = drv_tx(local, skb);
1177 if (WARN_ON(ret != NETDEV_TX_OK && skb->len != len)) {
1181 if (ret != NETDEV_TX_OK) {
1182 info->control.vif = &sdata->vif;
1183 return IEEE80211_TX_AGAIN;
1187 ieee80211_led_tx(local, 1);
1191 return IEEE80211_TX_OK;
1195 * Invoke TX handlers, return 0 on success and non-zero if the
1196 * frame was dropped or queued.
1198 static int invoke_tx_handlers(struct ieee80211_tx_data *tx)
1200 struct sk_buff *skb = tx->skb;
1201 ieee80211_tx_result res = TX_DROP;
1203 #define CALL_TXH(txh) \
1205 if (res != TX_CONTINUE) \
1208 CALL_TXH(ieee80211_tx_h_check_assoc)
1209 CALL_TXH(ieee80211_tx_h_ps_buf)
1210 CALL_TXH(ieee80211_tx_h_select_key)
1211 CALL_TXH(ieee80211_tx_h_michael_mic_add)
1212 CALL_TXH(ieee80211_tx_h_rate_ctrl)
1213 CALL_TXH(ieee80211_tx_h_misc)
1214 CALL_TXH(ieee80211_tx_h_sequence)
1215 CALL_TXH(ieee80211_tx_h_fragment)
1216 /* handlers after fragment must be aware of tx info fragmentation! */
1217 CALL_TXH(ieee80211_tx_h_stats)
1218 CALL_TXH(ieee80211_tx_h_encrypt)
1219 CALL_TXH(ieee80211_tx_h_calculate_duration)
1223 if (unlikely(res == TX_DROP)) {
1224 I802_DEBUG_INC(tx->local->tx_handlers_drop);
1226 struct sk_buff *next;
1233 } else if (unlikely(res == TX_QUEUED)) {
1234 I802_DEBUG_INC(tx->local->tx_handlers_queued);
1241 static void ieee80211_tx(struct ieee80211_sub_if_data *sdata,
1242 struct sk_buff *skb, bool txpending)
1244 struct ieee80211_local *local = sdata->local;
1245 struct ieee80211_tx_data tx;
1246 ieee80211_tx_result res_prepare;
1247 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1248 struct sk_buff *next;
1249 unsigned long flags;
1253 queue = skb_get_queue_mapping(skb);
1255 if (unlikely(skb->len < 10)) {
1262 /* initialises tx */
1263 res_prepare = ieee80211_tx_prepare(sdata, &tx, skb);
1265 if (unlikely(res_prepare == TX_DROP)) {
1269 } else if (unlikely(res_prepare == TX_QUEUED)) {
1274 tx.channel = local->hw.conf.channel;
1275 info->band = tx.channel->band;
1277 if (invoke_tx_handlers(&tx))
1282 ret = __ieee80211_tx(local, &tx.skb, tx.sta, txpending);
1284 case IEEE80211_TX_OK:
1286 case IEEE80211_TX_AGAIN:
1288 * Since there are no fragmented frames on A-MPDU
1289 * queues, there's no reason for a driver to reject
1290 * a frame there, warn and drop it.
1292 if (WARN_ON(info->flags & IEEE80211_TX_CTL_AMPDU))
1295 case IEEE80211_TX_PENDING:
1298 spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
1300 if (local->queue_stop_reasons[queue] ||
1301 !skb_queue_empty(&local->pending[queue])) {
1303 * if queue is stopped, queue up frames for later
1304 * transmission from the tasklet
1309 if (unlikely(txpending))
1310 __skb_queue_head(&local->pending[queue],
1313 __skb_queue_tail(&local->pending[queue],
1315 } while ((skb = next));
1317 spin_unlock_irqrestore(&local->queue_stop_reason_lock,
1321 * otherwise retry, but this is a race condition or
1322 * a driver bug (which we warn about if it persists)
1324 spin_unlock_irqrestore(&local->queue_stop_reason_lock,
1328 if (WARN(retries > 10, "tx refused but queue active\n"))
1348 /* device xmit handlers */
1350 static int ieee80211_skb_resize(struct ieee80211_local *local,
1351 struct sk_buff *skb,
1352 int head_need, bool may_encrypt)
1357 * This could be optimised, devices that do full hardware
1358 * crypto (including TKIP MMIC) need no tailroom... But we
1359 * have no drivers for such devices currently.
1362 tail_need = IEEE80211_ENCRYPT_TAILROOM;
1363 tail_need -= skb_tailroom(skb);
1364 tail_need = max_t(int, tail_need, 0);
1367 if (head_need || tail_need) {
1368 /* Sorry. Can't account for this any more */
1372 if (skb_header_cloned(skb))
1373 I802_DEBUG_INC(local->tx_expand_skb_head_cloned);
1375 I802_DEBUG_INC(local->tx_expand_skb_head);
1377 if (pskb_expand_head(skb, head_need, tail_need, GFP_ATOMIC)) {
1378 printk(KERN_DEBUG "%s: failed to reallocate TX buffer\n",
1379 wiphy_name(local->hw.wiphy));
1383 /* update truesize too */
1384 skb->truesize += head_need + tail_need;
1389 static bool need_dynamic_ps(struct ieee80211_local *local)
1391 /* driver doesn't support power save */
1392 if (!(local->hw.flags & IEEE80211_HW_SUPPORTS_PS))
1395 /* hardware does dynamic power save */
1396 if (local->hw.flags & IEEE80211_HW_SUPPORTS_DYNAMIC_PS)
1399 /* dynamic power save disabled */
1400 if (local->hw.conf.dynamic_ps_timeout <= 0)
1403 /* we are scanning, don't enable power save */
1404 if (local->scanning)
1407 if (!local->ps_sdata)
1413 static void ieee80211_xmit(struct ieee80211_sub_if_data *sdata,
1414 struct sk_buff *skb)
1416 struct ieee80211_local *local = sdata->local;
1417 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1418 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1419 struct ieee80211_sub_if_data *tmp_sdata;
1423 dev_hold(sdata->dev);
1425 if (need_dynamic_ps(local)) {
1426 if (local->hw.conf.flags & IEEE80211_CONF_PS) {
1427 ieee80211_stop_queues_by_reason(&local->hw,
1428 IEEE80211_QUEUE_STOP_REASON_PS);
1429 ieee80211_queue_work(&local->hw,
1430 &local->dynamic_ps_disable_work);
1433 mod_timer(&local->dynamic_ps_timer, jiffies +
1434 msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout));
1437 info->flags |= IEEE80211_TX_CTL_REQ_TX_STATUS;
1439 if (unlikely(sdata->vif.type == NL80211_IFTYPE_MONITOR)) {
1443 info->flags |= IEEE80211_TX_CTL_INJECTED;
1445 len_rthdr = ieee80211_get_radiotap_len(skb->data);
1446 hdr = (struct ieee80211_hdr *)(skb->data + len_rthdr);
1447 hdrlen = ieee80211_hdrlen(hdr->frame_control);
1449 /* check the header is complete in the frame */
1450 if (likely(skb->len >= len_rthdr + hdrlen)) {
1452 * We process outgoing injected frames that have a
1453 * local address we handle as though they are our
1455 * This code here isn't entirely correct, the local
1456 * MAC address is not necessarily enough to find
1457 * the interface to use; for that proper VLAN/WDS
1458 * support we will need a different mechanism.
1462 list_for_each_entry_rcu(tmp_sdata, &local->interfaces,
1464 if (!netif_running(tmp_sdata->dev))
1466 if (tmp_sdata->vif.type != NL80211_IFTYPE_AP)
1468 if (compare_ether_addr(tmp_sdata->dev->dev_addr,
1470 dev_hold(tmp_sdata->dev);
1471 dev_put(sdata->dev);
1480 may_encrypt = !(info->flags & IEEE80211_TX_INTFL_DONT_ENCRYPT);
1482 headroom = local->tx_headroom;
1484 headroom += IEEE80211_ENCRYPT_HEADROOM;
1485 headroom -= skb_headroom(skb);
1486 headroom = max_t(int, 0, headroom);
1488 if (ieee80211_skb_resize(local, skb, headroom, may_encrypt)) {
1490 dev_put(sdata->dev);
1494 info->control.vif = &sdata->vif;
1496 if (ieee80211_vif_is_mesh(&sdata->vif) &&
1497 ieee80211_is_data(hdr->frame_control) &&
1498 !is_multicast_ether_addr(hdr->addr1))
1499 if (mesh_nexthop_lookup(skb, sdata)) {
1500 /* skb queued: don't free */
1501 dev_put(sdata->dev);
1505 ieee80211_select_queue(local, skb);
1506 ieee80211_tx(sdata, skb, false);
1507 dev_put(sdata->dev);
1510 netdev_tx_t ieee80211_monitor_start_xmit(struct sk_buff *skb,
1511 struct net_device *dev)
1513 struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
1514 struct ieee80211_channel *chan = local->hw.conf.channel;
1515 struct ieee80211_radiotap_header *prthdr =
1516 (struct ieee80211_radiotap_header *)skb->data;
1517 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1521 * Frame injection is not allowed if beaconing is not allowed
1522 * or if we need radar detection. Beaconing is usually not allowed when
1523 * the mode or operation (Adhoc, AP, Mesh) does not support DFS.
1524 * Passive scan is also used in world regulatory domains where
1525 * your country is not known and as such it should be treated as
1526 * NO TX unless the channel is explicitly allowed in which case
1527 * your current regulatory domain would not have the passive scan
1530 * Since AP mode uses monitor interfaces to inject/TX management
1531 * frames we can make AP mode the exception to this rule once it
1532 * supports radar detection as its implementation can deal with
1533 * radar detection by itself. We can do that later by adding a
1534 * monitor flag interfaces used for AP support.
1536 if ((chan->flags & (IEEE80211_CHAN_NO_IBSS | IEEE80211_CHAN_RADAR |
1537 IEEE80211_CHAN_PASSIVE_SCAN)))
1540 /* check for not even having the fixed radiotap header part */
1541 if (unlikely(skb->len < sizeof(struct ieee80211_radiotap_header)))
1542 goto fail; /* too short to be possibly valid */
1544 /* is it a header version we can trust to find length from? */
1545 if (unlikely(prthdr->it_version))
1546 goto fail; /* only version 0 is supported */
1548 /* then there must be a radiotap header with a length we can use */
1549 len_rthdr = ieee80211_get_radiotap_len(skb->data);
1551 /* does the skb contain enough to deliver on the alleged length? */
1552 if (unlikely(skb->len < len_rthdr))
1553 goto fail; /* skb too short for claimed rt header extent */
1556 * fix up the pointers accounting for the radiotap
1557 * header still being in there. We are being given
1558 * a precooked IEEE80211 header so no need for
1561 skb_set_mac_header(skb, len_rthdr);
1563 * these are just fixed to the end of the rt area since we
1564 * don't have any better information and at this point, nobody cares
1566 skb_set_network_header(skb, len_rthdr);
1567 skb_set_transport_header(skb, len_rthdr);
1569 memset(info, 0, sizeof(*info));
1571 /* pass the radiotap header up to xmit */
1572 ieee80211_xmit(IEEE80211_DEV_TO_SUB_IF(dev), skb);
1573 return NETDEV_TX_OK;
1577 return NETDEV_TX_OK; /* meaning, we dealt with the skb */
1581 * ieee80211_subif_start_xmit - netif start_xmit function for Ethernet-type
1582 * subinterfaces (wlan#, WDS, and VLAN interfaces)
1583 * @skb: packet to be sent
1584 * @dev: incoming interface
1586 * Returns: 0 on success (and frees skb in this case) or 1 on failure (skb will
1587 * not be freed, and caller is responsible for either retrying later or freeing
1590 * This function takes in an Ethernet header and encapsulates it with suitable
1591 * IEEE 802.11 header based on which interface the packet is coming in. The
1592 * encapsulated packet will then be passed to master interface, wlan#.11, for
1593 * transmission (through low-level driver).
1595 netdev_tx_t ieee80211_subif_start_xmit(struct sk_buff *skb,
1596 struct net_device *dev)
1598 struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1599 struct ieee80211_local *local = sdata->local;
1600 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1601 int ret = NETDEV_TX_BUSY, head_need;
1602 u16 ethertype, hdrlen, meshhdrlen = 0;
1604 struct ieee80211_hdr hdr;
1605 struct ieee80211s_hdr mesh_hdr;
1606 const u8 *encaps_data;
1607 int encaps_len, skip_header_bytes;
1609 struct sta_info *sta;
1612 if (unlikely(skb->len < ETH_HLEN)) {
1617 nh_pos = skb_network_header(skb) - skb->data;
1618 h_pos = skb_transport_header(skb) - skb->data;
1620 /* convert Ethernet header to proper 802.11 header (based on
1621 * operation mode) */
1622 ethertype = (skb->data[12] << 8) | skb->data[13];
1623 fc = cpu_to_le16(IEEE80211_FTYPE_DATA | IEEE80211_STYPE_DATA);
1625 switch (sdata->vif.type) {
1626 case NL80211_IFTYPE_AP:
1627 case NL80211_IFTYPE_AP_VLAN:
1628 fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS);
1630 memcpy(hdr.addr1, skb->data, ETH_ALEN);
1631 memcpy(hdr.addr2, dev->dev_addr, ETH_ALEN);
1632 memcpy(hdr.addr3, skb->data + ETH_ALEN, ETH_ALEN);
1635 case NL80211_IFTYPE_WDS:
1636 fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS);
1638 memcpy(hdr.addr1, sdata->u.wds.remote_addr, ETH_ALEN);
1639 memcpy(hdr.addr2, dev->dev_addr, ETH_ALEN);
1640 memcpy(hdr.addr3, skb->data, ETH_ALEN);
1641 memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN);
1644 #ifdef CONFIG_MAC80211_MESH
1645 case NL80211_IFTYPE_MESH_POINT:
1646 if (!sdata->u.mesh.mshcfg.dot11MeshTTL) {
1647 /* Do not send frames with mesh_ttl == 0 */
1648 sdata->u.mesh.mshstats.dropped_frames_ttl++;
1653 if (compare_ether_addr(dev->dev_addr,
1654 skb->data + ETH_ALEN) == 0) {
1655 hdrlen = ieee80211_fill_mesh_addresses(&hdr, &fc,
1656 skb->data, skb->data + ETH_ALEN);
1657 meshhdrlen = ieee80211_new_mesh_header(&mesh_hdr,
1658 sdata, NULL, NULL, NULL);
1660 /* packet from other interface */
1661 struct mesh_path *mppath;
1662 int is_mesh_mcast = 1;
1666 if (is_multicast_ether_addr(skb->data))
1667 /* DA TA mSA AE:SA */
1668 mesh_da = skb->data;
1670 mppath = mpp_path_lookup(skb->data, sdata);
1672 /* RA TA mDA mSA AE:DA SA */
1673 mesh_da = mppath->mpp;
1676 /* DA TA mSA AE:SA */
1677 mesh_da = dev->broadcast;
1679 hdrlen = ieee80211_fill_mesh_addresses(&hdr, &fc,
1680 mesh_da, dev->dev_addr);
1684 ieee80211_new_mesh_header(&mesh_hdr,
1686 skb->data + ETH_ALEN,
1691 ieee80211_new_mesh_header(&mesh_hdr,
1695 skb->data + ETH_ALEN);
1700 case NL80211_IFTYPE_STATION:
1701 fc |= cpu_to_le16(IEEE80211_FCTL_TODS);
1703 memcpy(hdr.addr1, sdata->u.mgd.bssid, ETH_ALEN);
1704 memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
1705 memcpy(hdr.addr3, skb->data, ETH_ALEN);
1708 case NL80211_IFTYPE_ADHOC:
1710 memcpy(hdr.addr1, skb->data, ETH_ALEN);
1711 memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
1712 memcpy(hdr.addr3, sdata->u.ibss.bssid, ETH_ALEN);
1721 * There's no need to try to look up the destination
1722 * if it is a multicast address (which can only happen
1725 if (!is_multicast_ether_addr(hdr.addr1)) {
1727 sta = sta_info_get(local, hdr.addr1);
1728 /* XXX: in the future, use sdata to look up the sta */
1729 if (sta && sta->sdata == sdata)
1730 sta_flags = get_sta_flags(sta);
1734 /* receiver and we are QoS enabled, use a QoS type frame */
1735 if ((sta_flags & WLAN_STA_WME) && local->hw.queues >= 4) {
1736 fc |= cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
1741 * Drop unicast frames to unauthorised stations unless they are
1742 * EAPOL frames from the local station.
1744 if (!ieee80211_vif_is_mesh(&sdata->vif) &&
1745 unlikely(!is_multicast_ether_addr(hdr.addr1) &&
1746 !(sta_flags & WLAN_STA_AUTHORIZED) &&
1747 !(ethertype == ETH_P_PAE &&
1748 compare_ether_addr(dev->dev_addr,
1749 skb->data + ETH_ALEN) == 0))) {
1750 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
1751 if (net_ratelimit())
1752 printk(KERN_DEBUG "%s: dropped frame to %pM"
1753 " (unauthorized port)\n", dev->name,
1757 I802_DEBUG_INC(local->tx_handlers_drop_unauth_port);
1763 hdr.frame_control = fc;
1764 hdr.duration_id = 0;
1767 skip_header_bytes = ETH_HLEN;
1768 if (ethertype == ETH_P_AARP || ethertype == ETH_P_IPX) {
1769 encaps_data = bridge_tunnel_header;
1770 encaps_len = sizeof(bridge_tunnel_header);
1771 skip_header_bytes -= 2;
1772 } else if (ethertype >= 0x600) {
1773 encaps_data = rfc1042_header;
1774 encaps_len = sizeof(rfc1042_header);
1775 skip_header_bytes -= 2;
1781 skb_pull(skb, skip_header_bytes);
1782 nh_pos -= skip_header_bytes;
1783 h_pos -= skip_header_bytes;
1785 head_need = hdrlen + encaps_len + meshhdrlen - skb_headroom(skb);
1788 * So we need to modify the skb header and hence need a copy of
1789 * that. The head_need variable above doesn't, so far, include
1790 * the needed header space that we don't need right away. If we
1791 * can, then we don't reallocate right now but only after the
1792 * frame arrives at the master device (if it does...)
1794 * If we cannot, however, then we will reallocate to include all
1795 * the ever needed space. Also, if we need to reallocate it anyway,
1796 * make it big enough for everything we may ever need.
1799 if (head_need > 0 || skb_cloned(skb)) {
1800 head_need += IEEE80211_ENCRYPT_HEADROOM;
1801 head_need += local->tx_headroom;
1802 head_need = max_t(int, 0, head_need);
1803 if (ieee80211_skb_resize(local, skb, head_need, true))
1808 memcpy(skb_push(skb, encaps_len), encaps_data, encaps_len);
1809 nh_pos += encaps_len;
1810 h_pos += encaps_len;
1813 if (meshhdrlen > 0) {
1814 memcpy(skb_push(skb, meshhdrlen), &mesh_hdr, meshhdrlen);
1815 nh_pos += meshhdrlen;
1816 h_pos += meshhdrlen;
1819 if (ieee80211_is_data_qos(fc)) {
1820 __le16 *qos_control;
1822 qos_control = (__le16*) skb_push(skb, 2);
1823 memcpy(skb_push(skb, hdrlen - 2), &hdr, hdrlen - 2);
1825 * Maybe we could actually set some fields here, for now just
1826 * initialise to zero to indicate no special operation.
1830 memcpy(skb_push(skb, hdrlen), &hdr, hdrlen);
1835 dev->stats.tx_packets++;
1836 dev->stats.tx_bytes += skb->len;
1838 /* Update skb pointers to various headers since this modified frame
1839 * is going to go through Linux networking code that may potentially
1840 * need things like pointer to IP header. */
1841 skb_set_mac_header(skb, 0);
1842 skb_set_network_header(skb, nh_pos);
1843 skb_set_transport_header(skb, h_pos);
1845 memset(info, 0, sizeof(*info));
1847 dev->trans_start = jiffies;
1848 ieee80211_xmit(sdata, skb);
1850 return NETDEV_TX_OK;
1853 if (ret == NETDEV_TX_OK)
1861 * ieee80211_clear_tx_pending may not be called in a context where
1862 * it is possible that it packets could come in again.
1864 void ieee80211_clear_tx_pending(struct ieee80211_local *local)
1868 for (i = 0; i < local->hw.queues; i++)
1869 skb_queue_purge(&local->pending[i]);
1872 static bool ieee80211_tx_pending_skb(struct ieee80211_local *local,
1873 struct sk_buff *skb)
1875 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1876 struct ieee80211_sub_if_data *sdata;
1877 struct sta_info *sta;
1878 struct ieee80211_hdr *hdr;
1882 sdata = vif_to_sdata(info->control.vif);
1884 if (info->flags & IEEE80211_TX_INTFL_NEED_TXPROCESSING) {
1885 ieee80211_tx(sdata, skb, true);
1887 hdr = (struct ieee80211_hdr *)skb->data;
1888 sta = sta_info_get(local, hdr->addr1);
1890 ret = __ieee80211_tx(local, &skb, sta, true);
1891 if (ret != IEEE80211_TX_OK)
1899 * Transmit all pending packets. Called from tasklet.
1901 void ieee80211_tx_pending(unsigned long data)
1903 struct ieee80211_local *local = (struct ieee80211_local *)data;
1904 unsigned long flags;
1910 spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
1911 for (i = 0; i < local->hw.queues; i++) {
1913 * If queue is stopped by something other than due to pending
1914 * frames, or we have no pending frames, proceed to next queue.
1916 if (local->queue_stop_reasons[i] ||
1917 skb_queue_empty(&local->pending[i]))
1920 while (!skb_queue_empty(&local->pending[i])) {
1921 struct sk_buff *skb = __skb_dequeue(&local->pending[i]);
1922 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1923 struct ieee80211_sub_if_data *sdata;
1925 if (WARN_ON(!info->control.vif)) {
1930 sdata = vif_to_sdata(info->control.vif);
1931 dev_hold(sdata->dev);
1932 spin_unlock_irqrestore(&local->queue_stop_reason_lock,
1935 txok = ieee80211_tx_pending_skb(local, skb);
1936 dev_put(sdata->dev);
1938 __skb_queue_head(&local->pending[i], skb);
1939 spin_lock_irqsave(&local->queue_stop_reason_lock,
1945 spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
1950 /* functions for drivers to get certain frames */
1952 static void ieee80211_beacon_add_tim(struct ieee80211_if_ap *bss,
1953 struct sk_buff *skb,
1954 struct beacon_data *beacon)
1958 int i, have_bits = 0, n1, n2;
1960 /* Generate bitmap for TIM only if there are any STAs in power save
1962 if (atomic_read(&bss->num_sta_ps) > 0)
1963 /* in the hope that this is faster than
1964 * checking byte-for-byte */
1965 have_bits = !bitmap_empty((unsigned long*)bss->tim,
1966 IEEE80211_MAX_AID+1);
1968 if (bss->dtim_count == 0)
1969 bss->dtim_count = beacon->dtim_period - 1;
1973 tim = pos = (u8 *) skb_put(skb, 6);
1974 *pos++ = WLAN_EID_TIM;
1976 *pos++ = bss->dtim_count;
1977 *pos++ = beacon->dtim_period;
1979 if (bss->dtim_count == 0 && !skb_queue_empty(&bss->ps_bc_buf))
1983 /* Find largest even number N1 so that bits numbered 1 through
1984 * (N1 x 8) - 1 in the bitmap are 0 and number N2 so that bits
1985 * (N2 + 1) x 8 through 2007 are 0. */
1987 for (i = 0; i < IEEE80211_MAX_TIM_LEN; i++) {
1994 for (i = IEEE80211_MAX_TIM_LEN - 1; i >= n1; i--) {
2001 /* Bitmap control */
2003 /* Part Virt Bitmap */
2004 memcpy(pos, bss->tim + n1, n2 - n1 + 1);
2006 tim[1] = n2 - n1 + 4;
2007 skb_put(skb, n2 - n1);
2009 *pos++ = aid0; /* Bitmap control */
2010 *pos++ = 0; /* Part Virt Bitmap */
2014 struct sk_buff *ieee80211_beacon_get_tim(struct ieee80211_hw *hw,
2015 struct ieee80211_vif *vif,
2016 u16 *tim_offset, u16 *tim_length)
2018 struct ieee80211_local *local = hw_to_local(hw);
2019 struct sk_buff *skb = NULL;
2020 struct ieee80211_tx_info *info;
2021 struct ieee80211_sub_if_data *sdata = NULL;
2022 struct ieee80211_if_ap *ap = NULL;
2023 struct beacon_data *beacon;
2024 struct ieee80211_supported_band *sband;
2025 enum ieee80211_band band = local->hw.conf.channel->band;
2027 sband = local->hw.wiphy->bands[band];
2031 sdata = vif_to_sdata(vif);
2038 if (sdata->vif.type == NL80211_IFTYPE_AP) {
2040 beacon = rcu_dereference(ap->beacon);
2043 * headroom, head length,
2044 * tail length and maximum TIM length
2046 skb = dev_alloc_skb(local->tx_headroom +
2048 beacon->tail_len + 256);
2052 skb_reserve(skb, local->tx_headroom);
2053 memcpy(skb_put(skb, beacon->head_len), beacon->head,
2057 * Not very nice, but we want to allow the driver to call
2058 * ieee80211_beacon_get() as a response to the set_tim()
2059 * callback. That, however, is already invoked under the
2060 * sta_lock to guarantee consistent and race-free update
2061 * of the tim bitmap in mac80211 and the driver.
2063 if (local->tim_in_locked_section) {
2064 ieee80211_beacon_add_tim(ap, skb, beacon);
2066 unsigned long flags;
2068 spin_lock_irqsave(&local->sta_lock, flags);
2069 ieee80211_beacon_add_tim(ap, skb, beacon);
2070 spin_unlock_irqrestore(&local->sta_lock, flags);
2074 *tim_offset = beacon->head_len;
2076 *tim_length = skb->len - beacon->head_len;
2079 memcpy(skb_put(skb, beacon->tail_len),
2080 beacon->tail, beacon->tail_len);
2083 } else if (sdata->vif.type == NL80211_IFTYPE_ADHOC) {
2084 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
2085 struct ieee80211_hdr *hdr;
2086 struct sk_buff *presp = rcu_dereference(ifibss->presp);
2091 skb = skb_copy(presp, GFP_ATOMIC);
2095 hdr = (struct ieee80211_hdr *) skb->data;
2096 hdr->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
2097 IEEE80211_STYPE_BEACON);
2098 } else if (ieee80211_vif_is_mesh(&sdata->vif)) {
2099 struct ieee80211_mgmt *mgmt;
2102 /* headroom, head length, tail length and maximum TIM length */
2103 skb = dev_alloc_skb(local->tx_headroom + 400);
2107 skb_reserve(skb, local->hw.extra_tx_headroom);
2108 mgmt = (struct ieee80211_mgmt *)
2109 skb_put(skb, 24 + sizeof(mgmt->u.beacon));
2110 memset(mgmt, 0, 24 + sizeof(mgmt->u.beacon));
2111 mgmt->frame_control =
2112 cpu_to_le16(IEEE80211_FTYPE_MGMT | IEEE80211_STYPE_BEACON);
2113 memset(mgmt->da, 0xff, ETH_ALEN);
2114 memcpy(mgmt->sa, sdata->dev->dev_addr, ETH_ALEN);
2115 /* BSSID is left zeroed, wildcard value */
2116 mgmt->u.beacon.beacon_int =
2117 cpu_to_le16(sdata->vif.bss_conf.beacon_int);
2118 mgmt->u.beacon.capab_info = 0x0; /* 0x0 for MPs */
2120 pos = skb_put(skb, 2);
2121 *pos++ = WLAN_EID_SSID;
2124 mesh_mgmt_ies_add(skb, sdata);
2130 info = IEEE80211_SKB_CB(skb);
2132 info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
2135 * XXX: For now, always use the lowest rate
2137 info->control.rates[0].idx = 0;
2138 info->control.rates[0].count = 1;
2139 info->control.rates[1].idx = -1;
2140 info->control.rates[2].idx = -1;
2141 info->control.rates[3].idx = -1;
2142 info->control.rates[4].idx = -1;
2143 BUILD_BUG_ON(IEEE80211_TX_MAX_RATES != 5);
2145 info->control.vif = vif;
2147 info->flags |= IEEE80211_TX_CTL_NO_ACK;
2148 info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT;
2149 info->flags |= IEEE80211_TX_CTL_ASSIGN_SEQ;
2154 EXPORT_SYMBOL(ieee80211_beacon_get_tim);
2156 void ieee80211_rts_get(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
2157 const void *frame, size_t frame_len,
2158 const struct ieee80211_tx_info *frame_txctl,
2159 struct ieee80211_rts *rts)
2161 const struct ieee80211_hdr *hdr = frame;
2163 rts->frame_control =
2164 cpu_to_le16(IEEE80211_FTYPE_CTL | IEEE80211_STYPE_RTS);
2165 rts->duration = ieee80211_rts_duration(hw, vif, frame_len,
2167 memcpy(rts->ra, hdr->addr1, sizeof(rts->ra));
2168 memcpy(rts->ta, hdr->addr2, sizeof(rts->ta));
2170 EXPORT_SYMBOL(ieee80211_rts_get);
2172 void ieee80211_ctstoself_get(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
2173 const void *frame, size_t frame_len,
2174 const struct ieee80211_tx_info *frame_txctl,
2175 struct ieee80211_cts *cts)
2177 const struct ieee80211_hdr *hdr = frame;
2179 cts->frame_control =
2180 cpu_to_le16(IEEE80211_FTYPE_CTL | IEEE80211_STYPE_CTS);
2181 cts->duration = ieee80211_ctstoself_duration(hw, vif,
2182 frame_len, frame_txctl);
2183 memcpy(cts->ra, hdr->addr1, sizeof(cts->ra));
2185 EXPORT_SYMBOL(ieee80211_ctstoself_get);
2188 ieee80211_get_buffered_bc(struct ieee80211_hw *hw,
2189 struct ieee80211_vif *vif)
2191 struct ieee80211_local *local = hw_to_local(hw);
2192 struct sk_buff *skb = NULL;
2193 struct sta_info *sta;
2194 struct ieee80211_tx_data tx;
2195 struct ieee80211_sub_if_data *sdata;
2196 struct ieee80211_if_ap *bss = NULL;
2197 struct beacon_data *beacon;
2198 struct ieee80211_tx_info *info;
2200 sdata = vif_to_sdata(vif);
2204 beacon = rcu_dereference(bss->beacon);
2206 if (sdata->vif.type != NL80211_IFTYPE_AP || !beacon || !beacon->head)
2209 if (bss->dtim_count != 0)
2210 goto out; /* send buffered bc/mc only after DTIM beacon */
2213 skb = skb_dequeue(&bss->ps_bc_buf);
2216 local->total_ps_buffered--;
2218 if (!skb_queue_empty(&bss->ps_bc_buf) && skb->len >= 2) {
2219 struct ieee80211_hdr *hdr =
2220 (struct ieee80211_hdr *) skb->data;
2221 /* more buffered multicast/broadcast frames ==> set
2222 * MoreData flag in IEEE 802.11 header to inform PS
2224 hdr->frame_control |=
2225 cpu_to_le16(IEEE80211_FCTL_MOREDATA);
2228 if (!ieee80211_tx_prepare(sdata, &tx, skb))
2230 dev_kfree_skb_any(skb);
2233 info = IEEE80211_SKB_CB(skb);
2236 tx.flags |= IEEE80211_TX_PS_BUFFERED;
2237 tx.channel = local->hw.conf.channel;
2238 info->band = tx.channel->band;
2240 if (invoke_tx_handlers(&tx))
2247 EXPORT_SYMBOL(ieee80211_get_buffered_bc);
2249 void ieee80211_tx_skb(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb,
2252 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
2253 skb_set_mac_header(skb, 0);
2254 skb_set_network_header(skb, 0);
2255 skb_set_transport_header(skb, 0);
2258 info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
2261 * The other path calling ieee80211_xmit is from the tasklet,
2262 * and while we can handle concurrent transmissions locking
2263 * requirements are that we do not come into tx with bhs on.
2266 ieee80211_xmit(sdata, skb);