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(tx->local->sw_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 /* 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) >=
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",
333 dev_kfree_skb(skb_dequeue(&tx->sdata->bss->ps_bc_buf));
335 tx->local->total_ps_buffered++;
336 skb_queue_tail(&tx->sdata->bss->ps_bc_buf, tx->skb);
340 /* buffered in hardware */
341 info->flags |= IEEE80211_TX_CTL_SEND_AFTER_DTIM;
346 static int ieee80211_use_mfp(__le16 fc, struct sta_info *sta,
349 if (!ieee80211_is_mgmt(fc))
352 if (sta == NULL || !test_sta_flags(sta, WLAN_STA_MFP))
355 if (!ieee80211_is_robust_mgmt_frame((struct ieee80211_hdr *)
362 static ieee80211_tx_result
363 ieee80211_tx_h_unicast_ps_buf(struct ieee80211_tx_data *tx)
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;
370 if (unlikely(!sta || ieee80211_is_probe_resp(hdr->frame_control)))
373 staflags = get_sta_flags(sta);
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 "
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);
396 tx->local->total_ps_buffered++;
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);
402 info->control.jiffies = jiffies;
403 info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
404 skb_queue_tail(&sta->ps_tx_buf, tx->skb);
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,
413 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
414 if (test_and_clear_sta_flags(sta, WLAN_STA_PSPOLL)) {
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.
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.
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.
430 info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT;
435 static ieee80211_tx_result debug_noinline
436 ieee80211_tx_h_ps_buf(struct ieee80211_tx_data *tx)
438 if (unlikely(tx->flags & IEEE80211_TX_PS_BUFFERED))
441 if (tx->flags & IEEE80211_TX_UNICAST)
442 return ieee80211_tx_h_unicast_ps_buf(tx);
444 return ieee80211_tx_h_multicast_ps_buf(tx);
447 static ieee80211_tx_result debug_noinline
448 ieee80211_tx_h_select_key(struct ieee80211_tx_data *tx)
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;
454 if (unlikely(info->flags & IEEE80211_TX_INTFL_DONT_ENCRYPT))
456 else if (tx->sta && (key = rcu_dereference(tx->sta->key)))
458 else if (ieee80211_is_mgmt(hdr->frame_control) &&
459 (key = rcu_dereference(tx->sdata->default_mgmt_key)))
461 else if ((key = rcu_dereference(tx->sdata->default_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);
475 tx->key->tx_rx_count++;
476 /* TODO: add threshold stuff again */
478 switch (tx->key->conf.alg) {
480 if (ieee80211_is_auth(hdr->frame_control))
483 if (!ieee80211_is_data_present(hdr->frame_control))
487 if (!ieee80211_is_data_present(hdr->frame_control) &&
488 !ieee80211_use_mfp(hdr->frame_control, tx->sta,
493 if (!ieee80211_is_mgmt(hdr->frame_control))
499 if (!tx->key || !(tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))
500 info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
505 static ieee80211_tx_result debug_noinline
506 ieee80211_tx_h_rate_ctrl(struct ieee80211_tx_data *tx)
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;
513 bool inval = false, rts = false, short_preamble = false;
514 struct ieee80211_tx_rate_control txrc;
517 memset(&txrc, 0, sizeof(txrc));
519 sband = tx->local->hw.wiphy->bands[tx->channel->band];
521 len = min_t(int, tx->skb->len + FCS_LEN,
522 tx->local->hw.wiphy->frag_threshold);
524 /* set up the tx rate control struct we give the RC algo */
525 txrc.hw = local_to_hw(tx->local);
527 txrc.bss_conf = &tx->sdata->vif.bss_conf;
529 txrc.reported_rate.idx = -1;
530 txrc.max_rate_idx = tx->sdata->max_ratectrl_rateidx;
532 /* set up RTS protection if desired */
533 if (len > tx->local->hw.wiphy->rts_threshold) {
534 txrc.rts = rts = true;
538 * Use short preamble if the BSS can handle it, but not for
539 * management frames unless we know the receiver can handle
540 * that -- the management frame might be to a station that
541 * just wants a probe response.
543 if (tx->sdata->vif.bss_conf.use_short_preamble &&
544 (ieee80211_is_data(hdr->frame_control) ||
545 (tx->sta && test_sta_flags(tx->sta, WLAN_STA_SHORT_PREAMBLE))))
546 txrc.short_preamble = short_preamble = true;
548 sta_flags = tx->sta ? get_sta_flags(tx->sta) : 0;
551 * Lets not bother rate control if we're associated and cannot
552 * talk to the sta. This should not happen.
554 if (WARN((tx->local->sw_scanning) &&
555 (sta_flags & WLAN_STA_ASSOC) &&
556 !rate_usable_index_exists(sband, &tx->sta->sta),
557 "%s: Dropped data frame as no usable bitrate found while "
558 "scanning and associated. Target station: "
559 "%pM on %d GHz band\n",
560 tx->dev->name, hdr->addr1,
561 tx->channel->band ? 5 : 2))
565 * If we're associated with the sta at this point we know we can at
566 * least send the frame at the lowest bit rate.
568 rate_control_get_rate(tx->sdata, tx->sta, &txrc);
570 if (unlikely(info->control.rates[0].idx < 0))
573 if (txrc.reported_rate.idx < 0)
574 txrc.reported_rate = info->control.rates[0];
577 tx->sta->last_tx_rate = txrc.reported_rate;
579 if (unlikely(!info->control.rates[0].count))
580 info->control.rates[0].count = 1;
582 if (WARN_ON_ONCE((info->control.rates[0].count > 1) &&
583 (info->flags & IEEE80211_TX_CTL_NO_ACK)))
584 info->control.rates[0].count = 1;
586 if (is_multicast_ether_addr(hdr->addr1)) {
588 * XXX: verify the rate is in the basic rateset
594 * set up the RTS/CTS rate as the fastest basic rate
595 * that is not faster than the data rate
597 * XXX: Should this check all retry rates?
599 if (!(info->control.rates[0].flags & IEEE80211_TX_RC_MCS)) {
602 rate = &sband->bitrates[info->control.rates[0].idx];
604 for (i = 0; i < sband->n_bitrates; i++) {
605 /* must be a basic rate */
606 if (!(tx->sdata->vif.bss_conf.basic_rates & BIT(i)))
608 /* must not be faster than the data rate */
609 if (sband->bitrates[i].bitrate > rate->bitrate)
612 if (sband->bitrates[baserate].bitrate <
613 sband->bitrates[i].bitrate)
617 info->control.rts_cts_rate_idx = baserate;
620 for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) {
622 * make sure there's no valid rate following
623 * an invalid one, just in case drivers don't
624 * take the API seriously to stop at -1.
627 info->control.rates[i].idx = -1;
630 if (info->control.rates[i].idx < 0) {
636 * For now assume MCS is already set up correctly, this
639 if (info->control.rates[i].flags & IEEE80211_TX_RC_MCS) {
640 WARN_ON(info->control.rates[i].idx > 76);
644 /* set up RTS protection if desired */
646 info->control.rates[i].flags |=
647 IEEE80211_TX_RC_USE_RTS_CTS;
650 if (WARN_ON_ONCE(info->control.rates[i].idx >=
651 sband->n_bitrates)) {
652 info->control.rates[i].idx = -1;
656 rate = &sband->bitrates[info->control.rates[i].idx];
658 /* set up short preamble */
659 if (short_preamble &&
660 rate->flags & IEEE80211_RATE_SHORT_PREAMBLE)
661 info->control.rates[i].flags |=
662 IEEE80211_TX_RC_USE_SHORT_PREAMBLE;
664 /* set up G protection */
665 if (!rts && tx->sdata->vif.bss_conf.use_cts_prot &&
666 rate->flags & IEEE80211_RATE_ERP_G)
667 info->control.rates[i].flags |=
668 IEEE80211_TX_RC_USE_CTS_PROTECT;
674 static ieee80211_tx_result debug_noinline
675 ieee80211_tx_h_misc(struct ieee80211_tx_data *tx)
677 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
680 info->control.sta = &tx->sta->sta;
685 static ieee80211_tx_result debug_noinline
686 ieee80211_tx_h_sequence(struct ieee80211_tx_data *tx)
688 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
689 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
695 * Packet injection may want to control the sequence
696 * number, if we have no matching interface then we
697 * neither assign one ourselves nor ask the driver to.
699 if (unlikely(!info->control.vif))
702 if (unlikely(ieee80211_is_ctl(hdr->frame_control)))
705 if (ieee80211_hdrlen(hdr->frame_control) < 24)
709 * Anything but QoS data that has a sequence number field
710 * (is long enough) gets a sequence number from the global
713 if (!ieee80211_is_data_qos(hdr->frame_control)) {
714 /* driver should assign sequence number */
715 info->flags |= IEEE80211_TX_CTL_ASSIGN_SEQ;
716 /* for pure STA mode without beacons, we can do it */
717 hdr->seq_ctrl = cpu_to_le16(tx->sdata->sequence_number);
718 tx->sdata->sequence_number += 0x10;
719 tx->sdata->sequence_number &= IEEE80211_SCTL_SEQ;
724 * This should be true for injected/management frames only, for
725 * management frames we have set the IEEE80211_TX_CTL_ASSIGN_SEQ
726 * above since they are not QoS-data frames.
731 /* include per-STA, per-TID sequence counter */
733 qc = ieee80211_get_qos_ctl(hdr);
734 tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
735 seq = &tx->sta->tid_seq[tid];
737 hdr->seq_ctrl = cpu_to_le16(*seq);
739 /* Increase the sequence number. */
740 *seq = (*seq + 0x10) & IEEE80211_SCTL_SEQ;
745 static int ieee80211_fragment(struct ieee80211_local *local,
746 struct sk_buff *skb, int hdrlen,
749 struct sk_buff *tail = skb, *tmp;
750 int per_fragm = frag_threshold - hdrlen - FCS_LEN;
751 int pos = hdrlen + per_fragm;
752 int rem = skb->len - hdrlen - per_fragm;
754 if (WARN_ON(rem < 0))
758 int fraglen = per_fragm;
763 tmp = dev_alloc_skb(local->tx_headroom +
765 IEEE80211_ENCRYPT_HEADROOM +
766 IEEE80211_ENCRYPT_TAILROOM);
771 skb_reserve(tmp, local->tx_headroom +
772 IEEE80211_ENCRYPT_HEADROOM);
773 /* copy control information */
774 memcpy(tmp->cb, skb->cb, sizeof(tmp->cb));
775 skb_copy_queue_mapping(tmp, skb);
776 tmp->priority = skb->priority;
779 /* copy header and data */
780 memcpy(skb_put(tmp, hdrlen), skb->data, hdrlen);
781 memcpy(skb_put(tmp, fraglen), skb->data + pos, fraglen);
786 skb->len = hdrlen + per_fragm;
790 static ieee80211_tx_result debug_noinline
791 ieee80211_tx_h_fragment(struct ieee80211_tx_data *tx)
793 struct sk_buff *skb = tx->skb;
794 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
795 struct ieee80211_hdr *hdr = (void *)skb->data;
796 int frag_threshold = tx->local->hw.wiphy->frag_threshold;
800 if (!(tx->flags & IEEE80211_TX_FRAGMENTED))
804 * Warn when submitting a fragmented A-MPDU frame and drop it.
805 * This scenario is handled in ieee80211_tx_prepare but extra
806 * caution taken here as fragmented ampdu may cause Tx stop.
808 if (WARN_ON(info->flags & IEEE80211_TX_CTL_AMPDU))
811 hdrlen = ieee80211_hdrlen(hdr->frame_control);
813 /* internal error, why is TX_FRAGMENTED set? */
814 if (WARN_ON(skb->len + FCS_LEN <= frag_threshold))
818 * Now fragment the frame. This will allocate all the fragments and
819 * chain them (using skb as the first fragment) to skb->next.
820 * During transmission, we will remove the successfully transmitted
821 * fragments from this list. When the low-level driver rejects one
822 * of the fragments then we will simply pretend to accept the skb
823 * but store it away as pending.
825 if (ieee80211_fragment(tx->local, skb, hdrlen, frag_threshold))
828 /* update duration/seq/flags of fragments */
832 const __le16 morefrags = cpu_to_le16(IEEE80211_FCTL_MOREFRAGS);
834 hdr = (void *)skb->data;
835 info = IEEE80211_SKB_CB(skb);
838 hdr->frame_control |= morefrags;
839 next_len = skb->next->len;
841 * No multi-rate retries for fragmented frames, that
842 * would completely throw off the NAV at other STAs.
844 info->control.rates[1].idx = -1;
845 info->control.rates[2].idx = -1;
846 info->control.rates[3].idx = -1;
847 info->control.rates[4].idx = -1;
848 BUILD_BUG_ON(IEEE80211_TX_MAX_RATES != 5);
849 info->flags &= ~IEEE80211_TX_CTL_RATE_CTRL_PROBE;
851 hdr->frame_control &= ~morefrags;
854 hdr->duration_id = ieee80211_duration(tx, 0, next_len);
855 hdr->seq_ctrl |= cpu_to_le16(fragnum & IEEE80211_SCTL_FRAG);
857 } while ((skb = skb->next));
862 static ieee80211_tx_result debug_noinline
863 ieee80211_tx_h_encrypt(struct ieee80211_tx_data *tx)
868 switch (tx->key->conf.alg) {
870 return ieee80211_crypto_wep_encrypt(tx);
872 return ieee80211_crypto_tkip_encrypt(tx);
874 return ieee80211_crypto_ccmp_encrypt(tx);
876 return ieee80211_crypto_aes_cmac_encrypt(tx);
884 static ieee80211_tx_result debug_noinline
885 ieee80211_tx_h_calculate_duration(struct ieee80211_tx_data *tx)
887 struct sk_buff *skb = tx->skb;
888 struct ieee80211_hdr *hdr;
893 hdr = (void *) skb->data;
894 if (unlikely(ieee80211_is_pspoll(hdr->frame_control)))
895 break; /* must not overwrite AID */
896 next_len = skb->next ? skb->next->len : 0;
897 group_addr = is_multicast_ether_addr(hdr->addr1);
900 ieee80211_duration(tx, group_addr, next_len);
901 } while ((skb = skb->next));
906 static ieee80211_tx_result debug_noinline
907 ieee80211_tx_h_stats(struct ieee80211_tx_data *tx)
909 struct sk_buff *skb = tx->skb;
914 tx->sta->tx_packets++;
916 tx->sta->tx_fragments++;
917 tx->sta->tx_bytes += skb->len;
918 } while ((skb = skb->next));
923 /* actual transmit path */
926 * deal with packet injection down monitor interface
927 * with Radiotap Header -- only called for monitor mode interface
929 static bool __ieee80211_parse_tx_radiotap(struct ieee80211_tx_data *tx,
933 * this is the moment to interpret and discard the radiotap header that
934 * must be at the start of the packet injected in Monitor mode
936 * Need to take some care with endian-ness since radiotap
937 * args are little-endian
940 struct ieee80211_radiotap_iterator iterator;
941 struct ieee80211_radiotap_header *rthdr =
942 (struct ieee80211_radiotap_header *) skb->data;
943 struct ieee80211_supported_band *sband;
944 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
945 int ret = ieee80211_radiotap_iterator_init(&iterator, rthdr, skb->len);
947 sband = tx->local->hw.wiphy->bands[tx->channel->band];
949 info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
950 tx->flags &= ~IEEE80211_TX_FRAGMENTED;
953 * for every radiotap entry that is present
954 * (ieee80211_radiotap_iterator_next returns -ENOENT when no more
955 * entries present, or -EINVAL on error)
959 ret = ieee80211_radiotap_iterator_next(&iterator);
964 /* see if this argument is something we can use */
965 switch (iterator.this_arg_index) {
967 * You must take care when dereferencing iterator.this_arg
968 * for multibyte types... the pointer is not aligned. Use
969 * get_unaligned((type *)iterator.this_arg) to dereference
970 * iterator.this_arg for type "type" safely on all arches.
972 case IEEE80211_RADIOTAP_FLAGS:
973 if (*iterator.this_arg & IEEE80211_RADIOTAP_F_FCS) {
975 * this indicates that the skb we have been
976 * handed has the 32-bit FCS CRC at the end...
977 * we should react to that by snipping it off
978 * because it will be recomputed and added
981 if (skb->len < (iterator.max_length + FCS_LEN))
984 skb_trim(skb, skb->len - FCS_LEN);
986 if (*iterator.this_arg & IEEE80211_RADIOTAP_F_WEP)
987 info->flags &= ~IEEE80211_TX_INTFL_DONT_ENCRYPT;
988 if (*iterator.this_arg & IEEE80211_RADIOTAP_F_FRAG)
989 tx->flags |= IEEE80211_TX_FRAGMENTED;
993 * Please update the file
994 * Documentation/networking/mac80211-injection.txt
995 * when parsing new fields here.
1003 if (ret != -ENOENT) /* ie, if we didn't simply run out of fields */
1007 * remove the radiotap header
1008 * iterator->max_length was sanity-checked against
1009 * skb->len by iterator init
1011 skb_pull(skb, iterator.max_length);
1019 static ieee80211_tx_result
1020 ieee80211_tx_prepare(struct ieee80211_sub_if_data *sdata,
1021 struct ieee80211_tx_data *tx,
1022 struct sk_buff *skb)
1024 struct ieee80211_local *local = sdata->local;
1025 struct ieee80211_hdr *hdr;
1026 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1029 bool queued = false;
1031 memset(tx, 0, sizeof(*tx));
1033 tx->dev = sdata->dev; /* use original interface */
1036 tx->channel = local->hw.conf.channel;
1038 * Set this flag (used below to indicate "automatic fragmentation"),
1039 * it will be cleared/left by radiotap as desired.
1041 tx->flags |= IEEE80211_TX_FRAGMENTED;
1043 /* process and remove the injection radiotap header */
1044 if (unlikely(info->flags & IEEE80211_TX_CTL_INJECTED)) {
1045 if (!__ieee80211_parse_tx_radiotap(tx, skb))
1049 * __ieee80211_parse_tx_radiotap has now removed
1050 * the radiotap header that was present and pre-filled
1051 * 'tx' with tx control information.
1056 * If this flag is set to true anywhere, and we get here,
1057 * we are doing the needed processing, so remove the flag
1060 info->flags &= ~IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1062 hdr = (struct ieee80211_hdr *) skb->data;
1064 tx->sta = sta_info_get(local, hdr->addr1);
1066 if (tx->sta && ieee80211_is_data_qos(hdr->frame_control) &&
1067 (local->hw.flags & IEEE80211_HW_AMPDU_AGGREGATION)) {
1068 unsigned long flags;
1069 struct tid_ampdu_tx *tid_tx;
1071 qc = ieee80211_get_qos_ctl(hdr);
1072 tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
1074 spin_lock_irqsave(&tx->sta->lock, flags);
1076 * XXX: This spinlock could be fairly expensive, but see the
1077 * comment in agg-tx.c:ieee80211_agg_tx_operational().
1078 * One way to solve this would be to do something RCU-like
1079 * for managing the tid_tx struct and using atomic bitops
1080 * for the actual state -- by introducing an actual
1081 * 'operational' bit that would be possible. It would
1082 * require changing ieee80211_agg_tx_operational() to
1083 * set that bit, and changing the way tid_tx is managed
1084 * everywhere, including races between that bit and
1085 * tid_tx going away (tid_tx being added can be easily
1086 * committed to memory before the 'operational' bit).
1088 tid_tx = tx->sta->ampdu_mlme.tid_tx[tid];
1089 state = &tx->sta->ampdu_mlme.tid_state_tx[tid];
1090 if (*state == HT_AGG_STATE_OPERATIONAL) {
1091 info->flags |= IEEE80211_TX_CTL_AMPDU;
1092 } else if (*state != HT_AGG_STATE_IDLE) {
1095 info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1096 __skb_queue_tail(&tid_tx->pending, skb);
1098 spin_unlock_irqrestore(&tx->sta->lock, flags);
1100 if (unlikely(queued))
1104 if (is_multicast_ether_addr(hdr->addr1)) {
1105 tx->flags &= ~IEEE80211_TX_UNICAST;
1106 info->flags |= IEEE80211_TX_CTL_NO_ACK;
1108 tx->flags |= IEEE80211_TX_UNICAST;
1109 if (unlikely(local->wifi_wme_noack_test))
1110 info->flags |= IEEE80211_TX_CTL_NO_ACK;
1112 info->flags &= ~IEEE80211_TX_CTL_NO_ACK;
1115 if (tx->flags & IEEE80211_TX_FRAGMENTED) {
1116 if ((tx->flags & IEEE80211_TX_UNICAST) &&
1117 skb->len + FCS_LEN > local->hw.wiphy->frag_threshold &&
1118 !(info->flags & IEEE80211_TX_CTL_AMPDU))
1119 tx->flags |= IEEE80211_TX_FRAGMENTED;
1121 tx->flags &= ~IEEE80211_TX_FRAGMENTED;
1125 info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT;
1126 else if (test_and_clear_sta_flags(tx->sta, WLAN_STA_CLEAR_PS_FILT))
1127 info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT;
1129 hdrlen = ieee80211_hdrlen(hdr->frame_control);
1130 if (skb->len > hdrlen + sizeof(rfc1042_header) + 2) {
1131 u8 *pos = &skb->data[hdrlen + sizeof(rfc1042_header)];
1132 tx->ethertype = (pos[0] << 8) | pos[1];
1134 info->flags |= IEEE80211_TX_CTL_FIRST_FRAGMENT;
1139 static int __ieee80211_tx(struct ieee80211_local *local,
1140 struct sk_buff **skbp,
1141 struct sta_info *sta,
1144 struct sk_buff *skb = *skbp, *next;
1145 struct ieee80211_tx_info *info;
1146 unsigned long flags;
1151 int q = skb_get_queue_mapping(skb);
1153 spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
1154 ret = IEEE80211_TX_OK;
1155 if (local->queue_stop_reasons[q] ||
1156 (!txpending && !skb_queue_empty(&local->pending[q])))
1157 ret = IEEE80211_TX_PENDING;
1158 spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
1159 if (ret != IEEE80211_TX_OK)
1162 info = IEEE80211_SKB_CB(skb);
1165 info->flags &= ~(IEEE80211_TX_CTL_CLEAR_PS_FILT |
1166 IEEE80211_TX_CTL_FIRST_FRAGMENT);
1170 ret = drv_tx(local, skb);
1171 if (WARN_ON(ret != NETDEV_TX_OK && skb->len != len)) {
1175 if (ret != NETDEV_TX_OK)
1176 return IEEE80211_TX_AGAIN;
1178 ieee80211_led_tx(local, 1);
1182 return IEEE80211_TX_OK;
1186 * Invoke TX handlers, return 0 on success and non-zero if the
1187 * frame was dropped or queued.
1189 static int invoke_tx_handlers(struct ieee80211_tx_data *tx)
1191 struct sk_buff *skb = tx->skb;
1192 ieee80211_tx_result res = TX_DROP;
1194 #define CALL_TXH(txh) \
1196 if (res != TX_CONTINUE) \
1199 CALL_TXH(ieee80211_tx_h_check_assoc)
1200 CALL_TXH(ieee80211_tx_h_ps_buf)
1201 CALL_TXH(ieee80211_tx_h_select_key)
1202 CALL_TXH(ieee80211_tx_h_michael_mic_add)
1203 CALL_TXH(ieee80211_tx_h_rate_ctrl)
1204 CALL_TXH(ieee80211_tx_h_misc)
1205 CALL_TXH(ieee80211_tx_h_sequence)
1206 CALL_TXH(ieee80211_tx_h_fragment)
1207 /* handlers after fragment must be aware of tx info fragmentation! */
1208 CALL_TXH(ieee80211_tx_h_encrypt)
1209 CALL_TXH(ieee80211_tx_h_calculate_duration)
1210 CALL_TXH(ieee80211_tx_h_stats)
1214 if (unlikely(res == TX_DROP)) {
1215 I802_DEBUG_INC(tx->local->tx_handlers_drop);
1217 struct sk_buff *next;
1224 } else if (unlikely(res == TX_QUEUED)) {
1225 I802_DEBUG_INC(tx->local->tx_handlers_queued);
1232 static void ieee80211_tx(struct ieee80211_sub_if_data *sdata,
1233 struct sk_buff *skb, bool txpending)
1235 struct ieee80211_local *local = sdata->local;
1236 struct ieee80211_tx_data tx;
1237 ieee80211_tx_result res_prepare;
1238 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1239 struct sk_buff *next;
1240 unsigned long flags;
1244 queue = skb_get_queue_mapping(skb);
1246 if (unlikely(skb->len < 10)) {
1253 /* initialises tx */
1254 res_prepare = ieee80211_tx_prepare(sdata, &tx, skb);
1256 if (unlikely(res_prepare == TX_DROP)) {
1260 } else if (unlikely(res_prepare == TX_QUEUED)) {
1265 tx.channel = local->hw.conf.channel;
1266 info->band = tx.channel->band;
1268 if (invoke_tx_handlers(&tx))
1273 ret = __ieee80211_tx(local, &tx.skb, tx.sta, txpending);
1275 case IEEE80211_TX_OK:
1277 case IEEE80211_TX_AGAIN:
1279 * Since there are no fragmented frames on A-MPDU
1280 * queues, there's no reason for a driver to reject
1281 * a frame there, warn and drop it.
1283 if (WARN_ON(info->flags & IEEE80211_TX_CTL_AMPDU))
1286 case IEEE80211_TX_PENDING:
1289 spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
1291 if (local->queue_stop_reasons[queue] ||
1292 !skb_queue_empty(&local->pending[queue])) {
1294 * if queue is stopped, queue up frames for later
1295 * transmission from the tasklet
1300 if (unlikely(txpending))
1301 __skb_queue_head(&local->pending[queue],
1304 __skb_queue_tail(&local->pending[queue],
1306 } while ((skb = next));
1308 spin_unlock_irqrestore(&local->queue_stop_reason_lock,
1312 * otherwise retry, but this is a race condition or
1313 * a driver bug (which we warn about if it persists)
1315 spin_unlock_irqrestore(&local->queue_stop_reason_lock,
1319 if (WARN(retries > 10, "tx refused but queue active\n"))
1339 /* device xmit handlers */
1341 static int ieee80211_skb_resize(struct ieee80211_local *local,
1342 struct sk_buff *skb,
1343 int head_need, bool may_encrypt)
1348 * This could be optimised, devices that do full hardware
1349 * crypto (including TKIP MMIC) need no tailroom... But we
1350 * have no drivers for such devices currently.
1353 tail_need = IEEE80211_ENCRYPT_TAILROOM;
1354 tail_need -= skb_tailroom(skb);
1355 tail_need = max_t(int, tail_need, 0);
1358 if (head_need || tail_need) {
1359 /* Sorry. Can't account for this any more */
1363 if (skb_header_cloned(skb))
1364 I802_DEBUG_INC(local->tx_expand_skb_head_cloned);
1366 I802_DEBUG_INC(local->tx_expand_skb_head);
1368 if (pskb_expand_head(skb, head_need, tail_need, GFP_ATOMIC)) {
1369 printk(KERN_DEBUG "%s: failed to reallocate TX buffer\n",
1370 wiphy_name(local->hw.wiphy));
1374 /* update truesize too */
1375 skb->truesize += head_need + tail_need;
1380 static void ieee80211_xmit(struct ieee80211_sub_if_data *sdata,
1381 struct sk_buff *skb)
1383 struct ieee80211_local *local = sdata->local;
1384 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1385 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1386 struct ieee80211_sub_if_data *tmp_sdata;
1393 } monitor_iface = NOT_MONITOR;
1395 dev_hold(sdata->dev);
1397 if ((local->hw.flags & IEEE80211_HW_PS_NULLFUNC_STACK) &&
1398 local->hw.conf.dynamic_ps_timeout > 0 &&
1399 !local->sw_scanning && !local->hw_scanning && local->ps_sdata) {
1400 if (local->hw.conf.flags & IEEE80211_CONF_PS) {
1401 ieee80211_stop_queues_by_reason(&local->hw,
1402 IEEE80211_QUEUE_STOP_REASON_PS);
1403 queue_work(local->hw.workqueue,
1404 &local->dynamic_ps_disable_work);
1407 mod_timer(&local->dynamic_ps_timer, jiffies +
1408 msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout));
1411 info->flags |= IEEE80211_TX_CTL_REQ_TX_STATUS;
1413 if (ieee80211_vif_is_mesh(&sdata->vif) &&
1414 ieee80211_is_data(hdr->frame_control)) {
1415 if (is_multicast_ether_addr(hdr->addr3))
1416 memcpy(hdr->addr1, hdr->addr3, ETH_ALEN);
1418 if (mesh_nexthop_lookup(skb, sdata)) {
1419 dev_put(sdata->dev);
1422 } else if (unlikely(sdata->vif.type == NL80211_IFTYPE_MONITOR)) {
1426 info->flags |= IEEE80211_TX_CTL_INJECTED;
1427 monitor_iface = UNKNOWN_ADDRESS;
1429 len_rthdr = ieee80211_get_radiotap_len(skb->data);
1430 hdr = (struct ieee80211_hdr *)(skb->data + len_rthdr);
1431 hdrlen = ieee80211_hdrlen(hdr->frame_control);
1433 /* check the header is complete in the frame */
1434 if (likely(skb->len >= len_rthdr + hdrlen)) {
1436 * We process outgoing injected frames that have a
1437 * local address we handle as though they are our
1439 * This code here isn't entirely correct, the local
1440 * MAC address is not necessarily enough to find
1441 * the interface to use; for that proper VLAN/WDS
1442 * support we will need a different mechanism.
1446 list_for_each_entry_rcu(tmp_sdata, &local->interfaces,
1448 if (!netif_running(tmp_sdata->dev))
1450 if (tmp_sdata->vif.type != NL80211_IFTYPE_AP)
1452 if (compare_ether_addr(tmp_sdata->dev->dev_addr,
1454 dev_hold(tmp_sdata->dev);
1455 dev_put(sdata->dev);
1457 monitor_iface = FOUND_SDATA;
1465 may_encrypt = !(info->flags & IEEE80211_TX_INTFL_DONT_ENCRYPT);
1467 headroom = local->tx_headroom;
1469 headroom += IEEE80211_ENCRYPT_HEADROOM;
1470 headroom -= skb_headroom(skb);
1471 headroom = max_t(int, 0, headroom);
1473 if (ieee80211_skb_resize(local, skb, headroom, may_encrypt)) {
1475 dev_put(sdata->dev);
1480 if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
1481 tmp_sdata = container_of(sdata->bss,
1482 struct ieee80211_sub_if_data,
1484 if (likely(monitor_iface != UNKNOWN_ADDRESS))
1485 info->control.vif = &tmp_sdata->vif;
1487 ieee80211_select_queue(local, skb);
1488 ieee80211_tx(sdata, skb, false);
1489 dev_put(sdata->dev);
1492 int ieee80211_monitor_start_xmit(struct sk_buff *skb,
1493 struct net_device *dev)
1495 struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
1496 struct ieee80211_channel *chan = local->hw.conf.channel;
1497 struct ieee80211_radiotap_header *prthdr =
1498 (struct ieee80211_radiotap_header *)skb->data;
1499 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1503 * Frame injection is not allowed if beaconing is not allowed
1504 * or if we need radar detection. Beaconing is usually not allowed when
1505 * the mode or operation (Adhoc, AP, Mesh) does not support DFS.
1506 * Passive scan is also used in world regulatory domains where
1507 * your country is not known and as such it should be treated as
1508 * NO TX unless the channel is explicitly allowed in which case
1509 * your current regulatory domain would not have the passive scan
1512 * Since AP mode uses monitor interfaces to inject/TX management
1513 * frames we can make AP mode the exception to this rule once it
1514 * supports radar detection as its implementation can deal with
1515 * radar detection by itself. We can do that later by adding a
1516 * monitor flag interfaces used for AP support.
1518 if ((chan->flags & (IEEE80211_CHAN_NO_IBSS | IEEE80211_CHAN_RADAR |
1519 IEEE80211_CHAN_PASSIVE_SCAN)))
1522 /* check for not even having the fixed radiotap header part */
1523 if (unlikely(skb->len < sizeof(struct ieee80211_radiotap_header)))
1524 goto fail; /* too short to be possibly valid */
1526 /* is it a header version we can trust to find length from? */
1527 if (unlikely(prthdr->it_version))
1528 goto fail; /* only version 0 is supported */
1530 /* then there must be a radiotap header with a length we can use */
1531 len_rthdr = ieee80211_get_radiotap_len(skb->data);
1533 /* does the skb contain enough to deliver on the alleged length? */
1534 if (unlikely(skb->len < len_rthdr))
1535 goto fail; /* skb too short for claimed rt header extent */
1537 /* needed because we set skb device to master */
1538 skb->iif = dev->ifindex;
1541 * fix up the pointers accounting for the radiotap
1542 * header still being in there. We are being given
1543 * a precooked IEEE80211 header so no need for
1546 skb_set_mac_header(skb, len_rthdr);
1548 * these are just fixed to the end of the rt area since we
1549 * don't have any better information and at this point, nobody cares
1551 skb_set_network_header(skb, len_rthdr);
1552 skb_set_transport_header(skb, len_rthdr);
1554 memset(info, 0, sizeof(*info));
1556 /* pass the radiotap header up to xmit */
1557 ieee80211_xmit(IEEE80211_DEV_TO_SUB_IF(dev), skb);
1558 return NETDEV_TX_OK;
1562 return NETDEV_TX_OK; /* meaning, we dealt with the skb */
1566 * ieee80211_subif_start_xmit - netif start_xmit function for Ethernet-type
1567 * subinterfaces (wlan#, WDS, and VLAN interfaces)
1568 * @skb: packet to be sent
1569 * @dev: incoming interface
1571 * Returns: 0 on success (and frees skb in this case) or 1 on failure (skb will
1572 * not be freed, and caller is responsible for either retrying later or freeing
1575 * This function takes in an Ethernet header and encapsulates it with suitable
1576 * IEEE 802.11 header based on which interface the packet is coming in. The
1577 * encapsulated packet will then be passed to master interface, wlan#.11, for
1578 * transmission (through low-level driver).
1580 int ieee80211_subif_start_xmit(struct sk_buff *skb,
1581 struct net_device *dev)
1583 struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1584 struct ieee80211_local *local = sdata->local;
1585 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1586 int ret = NETDEV_TX_BUSY, head_need;
1587 u16 ethertype, hdrlen, meshhdrlen = 0;
1589 struct ieee80211_hdr hdr;
1590 struct ieee80211s_hdr mesh_hdr;
1591 const u8 *encaps_data;
1592 int encaps_len, skip_header_bytes;
1594 struct sta_info *sta;
1597 if (unlikely(skb->len < ETH_HLEN)) {
1602 nh_pos = skb_network_header(skb) - skb->data;
1603 h_pos = skb_transport_header(skb) - skb->data;
1605 /* convert Ethernet header to proper 802.11 header (based on
1606 * operation mode) */
1607 ethertype = (skb->data[12] << 8) | skb->data[13];
1608 fc = cpu_to_le16(IEEE80211_FTYPE_DATA | IEEE80211_STYPE_DATA);
1610 switch (sdata->vif.type) {
1611 case NL80211_IFTYPE_AP:
1612 case NL80211_IFTYPE_AP_VLAN:
1613 fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS);
1615 memcpy(hdr.addr1, skb->data, ETH_ALEN);
1616 memcpy(hdr.addr2, dev->dev_addr, ETH_ALEN);
1617 memcpy(hdr.addr3, skb->data + ETH_ALEN, ETH_ALEN);
1620 case NL80211_IFTYPE_WDS:
1621 fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS);
1623 memcpy(hdr.addr1, sdata->u.wds.remote_addr, ETH_ALEN);
1624 memcpy(hdr.addr2, dev->dev_addr, ETH_ALEN);
1625 memcpy(hdr.addr3, skb->data, ETH_ALEN);
1626 memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN);
1629 #ifdef CONFIG_MAC80211_MESH
1630 case NL80211_IFTYPE_MESH_POINT:
1631 fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS);
1632 if (!sdata->u.mesh.mshcfg.dot11MeshTTL) {
1633 /* Do not send frames with mesh_ttl == 0 */
1634 sdata->u.mesh.mshstats.dropped_frames_ttl++;
1638 memset(&mesh_hdr, 0, sizeof(mesh_hdr));
1640 if (compare_ether_addr(dev->dev_addr,
1641 skb->data + ETH_ALEN) == 0) {
1643 memset(hdr.addr1, 0, ETH_ALEN);
1644 memcpy(hdr.addr2, dev->dev_addr, ETH_ALEN);
1645 memcpy(hdr.addr3, skb->data, ETH_ALEN);
1646 memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN);
1647 meshhdrlen = ieee80211_new_mesh_header(&mesh_hdr, sdata);
1649 /* packet from other interface */
1650 struct mesh_path *mppath;
1652 memset(hdr.addr1, 0, ETH_ALEN);
1653 memcpy(hdr.addr2, dev->dev_addr, ETH_ALEN);
1654 memcpy(hdr.addr4, dev->dev_addr, ETH_ALEN);
1656 if (is_multicast_ether_addr(skb->data))
1657 memcpy(hdr.addr3, skb->data, ETH_ALEN);
1660 mppath = mpp_path_lookup(skb->data, sdata);
1662 memcpy(hdr.addr3, mppath->mpp, ETH_ALEN);
1664 memset(hdr.addr3, 0xff, ETH_ALEN);
1668 mesh_hdr.flags |= MESH_FLAGS_AE_A5_A6;
1669 mesh_hdr.ttl = sdata->u.mesh.mshcfg.dot11MeshTTL;
1670 put_unaligned(cpu_to_le32(sdata->u.mesh.mesh_seqnum), &mesh_hdr.seqnum);
1671 memcpy(mesh_hdr.eaddr1, skb->data, ETH_ALEN);
1672 memcpy(mesh_hdr.eaddr2, skb->data + ETH_ALEN, ETH_ALEN);
1673 sdata->u.mesh.mesh_seqnum++;
1679 case NL80211_IFTYPE_STATION:
1680 fc |= cpu_to_le16(IEEE80211_FCTL_TODS);
1682 memcpy(hdr.addr1, sdata->u.mgd.bssid, ETH_ALEN);
1683 memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
1684 memcpy(hdr.addr3, skb->data, ETH_ALEN);
1687 case NL80211_IFTYPE_ADHOC:
1689 memcpy(hdr.addr1, skb->data, ETH_ALEN);
1690 memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
1691 memcpy(hdr.addr3, sdata->u.ibss.bssid, ETH_ALEN);
1700 * There's no need to try to look up the destination
1701 * if it is a multicast address (which can only happen
1704 if (!is_multicast_ether_addr(hdr.addr1)) {
1706 sta = sta_info_get(local, hdr.addr1);
1708 sta_flags = get_sta_flags(sta);
1712 /* receiver and we are QoS enabled, use a QoS type frame */
1713 if ((sta_flags & WLAN_STA_WME) && local->hw.queues >= 4) {
1714 fc |= cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
1719 * Drop unicast frames to unauthorised stations unless they are
1720 * EAPOL frames from the local station.
1722 if (!ieee80211_vif_is_mesh(&sdata->vif) &&
1723 unlikely(!is_multicast_ether_addr(hdr.addr1) &&
1724 !(sta_flags & WLAN_STA_AUTHORIZED) &&
1725 !(ethertype == ETH_P_PAE &&
1726 compare_ether_addr(dev->dev_addr,
1727 skb->data + ETH_ALEN) == 0))) {
1728 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
1729 if (net_ratelimit())
1730 printk(KERN_DEBUG "%s: dropped frame to %pM"
1731 " (unauthorized port)\n", dev->name,
1735 I802_DEBUG_INC(local->tx_handlers_drop_unauth_port);
1741 hdr.frame_control = fc;
1742 hdr.duration_id = 0;
1745 skip_header_bytes = ETH_HLEN;
1746 if (ethertype == ETH_P_AARP || ethertype == ETH_P_IPX) {
1747 encaps_data = bridge_tunnel_header;
1748 encaps_len = sizeof(bridge_tunnel_header);
1749 skip_header_bytes -= 2;
1750 } else if (ethertype >= 0x600) {
1751 encaps_data = rfc1042_header;
1752 encaps_len = sizeof(rfc1042_header);
1753 skip_header_bytes -= 2;
1759 skb_pull(skb, skip_header_bytes);
1760 nh_pos -= skip_header_bytes;
1761 h_pos -= skip_header_bytes;
1763 head_need = hdrlen + encaps_len + meshhdrlen - skb_headroom(skb);
1766 * So we need to modify the skb header and hence need a copy of
1767 * that. The head_need variable above doesn't, so far, include
1768 * the needed header space that we don't need right away. If we
1769 * can, then we don't reallocate right now but only after the
1770 * frame arrives at the master device (if it does...)
1772 * If we cannot, however, then we will reallocate to include all
1773 * the ever needed space. Also, if we need to reallocate it anyway,
1774 * make it big enough for everything we may ever need.
1777 if (head_need > 0 || skb_cloned(skb)) {
1778 head_need += IEEE80211_ENCRYPT_HEADROOM;
1779 head_need += local->tx_headroom;
1780 head_need = max_t(int, 0, head_need);
1781 if (ieee80211_skb_resize(local, skb, head_need, true))
1786 memcpy(skb_push(skb, encaps_len), encaps_data, encaps_len);
1787 nh_pos += encaps_len;
1788 h_pos += encaps_len;
1791 if (meshhdrlen > 0) {
1792 memcpy(skb_push(skb, meshhdrlen), &mesh_hdr, meshhdrlen);
1793 nh_pos += meshhdrlen;
1794 h_pos += meshhdrlen;
1797 if (ieee80211_is_data_qos(fc)) {
1798 __le16 *qos_control;
1800 qos_control = (__le16*) skb_push(skb, 2);
1801 memcpy(skb_push(skb, hdrlen - 2), &hdr, hdrlen - 2);
1803 * Maybe we could actually set some fields here, for now just
1804 * initialise to zero to indicate no special operation.
1808 memcpy(skb_push(skb, hdrlen), &hdr, hdrlen);
1813 skb->iif = dev->ifindex;
1815 dev->stats.tx_packets++;
1816 dev->stats.tx_bytes += skb->len;
1818 /* Update skb pointers to various headers since this modified frame
1819 * is going to go through Linux networking code that may potentially
1820 * need things like pointer to IP header. */
1821 skb_set_mac_header(skb, 0);
1822 skb_set_network_header(skb, nh_pos);
1823 skb_set_transport_header(skb, h_pos);
1825 memset(info, 0, sizeof(*info));
1827 dev->trans_start = jiffies;
1828 ieee80211_xmit(sdata, skb);
1830 return NETDEV_TX_OK;
1833 if (ret == NETDEV_TX_OK)
1841 * ieee80211_clear_tx_pending may not be called in a context where
1842 * it is possible that it packets could come in again.
1844 void ieee80211_clear_tx_pending(struct ieee80211_local *local)
1848 for (i = 0; i < local->hw.queues; i++)
1849 skb_queue_purge(&local->pending[i]);
1852 static bool ieee80211_tx_pending_skb(struct ieee80211_local *local,
1853 struct sk_buff *skb)
1855 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1856 struct ieee80211_sub_if_data *sdata;
1857 struct sta_info *sta;
1858 struct ieee80211_hdr *hdr;
1859 struct net_device *dev;
1863 /* does interface still exist? */
1864 dev = dev_get_by_index(&init_net, skb->iif);
1870 sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1871 if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
1872 sdata = container_of(sdata->bss,
1873 struct ieee80211_sub_if_data,
1876 if (unlikely(info->control.vif && info->control.vif != &sdata->vif)) {
1882 if (info->flags & IEEE80211_TX_INTFL_NEED_TXPROCESSING) {
1883 /* do not use sdata, it may have been changed above */
1884 ieee80211_tx(IEEE80211_DEV_TO_SUB_IF(dev), skb, true);
1886 hdr = (struct ieee80211_hdr *)skb->data;
1887 sta = sta_info_get(local, hdr->addr1);
1889 ret = __ieee80211_tx(local, &skb, sta, true);
1890 if (ret != IEEE80211_TX_OK)
1901 * Transmit all pending packets. Called from tasklet.
1903 void ieee80211_tx_pending(unsigned long data)
1905 struct ieee80211_local *local = (struct ieee80211_local *)data;
1906 unsigned long flags;
1912 spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
1913 for (i = 0; i < local->hw.queues; i++) {
1915 * If queue is stopped by something other than due to pending
1916 * frames, or we have no pending frames, proceed to next queue.
1918 if (local->queue_stop_reasons[i] ||
1919 skb_queue_empty(&local->pending[i]))
1922 while (!skb_queue_empty(&local->pending[i])) {
1923 struct sk_buff *skb = __skb_dequeue(&local->pending[i]);
1924 spin_unlock_irqrestore(&local->queue_stop_reason_lock,
1927 txok = ieee80211_tx_pending_skb(local, skb);
1929 __skb_queue_head(&local->pending[i], skb);
1930 spin_lock_irqsave(&local->queue_stop_reason_lock,
1936 spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
1941 /* functions for drivers to get certain frames */
1943 static void ieee80211_beacon_add_tim(struct ieee80211_if_ap *bss,
1944 struct sk_buff *skb,
1945 struct beacon_data *beacon)
1949 int i, have_bits = 0, n1, n2;
1951 /* Generate bitmap for TIM only if there are any STAs in power save
1953 if (atomic_read(&bss->num_sta_ps) > 0)
1954 /* in the hope that this is faster than
1955 * checking byte-for-byte */
1956 have_bits = !bitmap_empty((unsigned long*)bss->tim,
1957 IEEE80211_MAX_AID+1);
1959 if (bss->dtim_count == 0)
1960 bss->dtim_count = beacon->dtim_period - 1;
1964 tim = pos = (u8 *) skb_put(skb, 6);
1965 *pos++ = WLAN_EID_TIM;
1967 *pos++ = bss->dtim_count;
1968 *pos++ = beacon->dtim_period;
1970 if (bss->dtim_count == 0 && !skb_queue_empty(&bss->ps_bc_buf))
1974 /* Find largest even number N1 so that bits numbered 1 through
1975 * (N1 x 8) - 1 in the bitmap are 0 and number N2 so that bits
1976 * (N2 + 1) x 8 through 2007 are 0. */
1978 for (i = 0; i < IEEE80211_MAX_TIM_LEN; i++) {
1985 for (i = IEEE80211_MAX_TIM_LEN - 1; i >= n1; i--) {
1992 /* Bitmap control */
1994 /* Part Virt Bitmap */
1995 memcpy(pos, bss->tim + n1, n2 - n1 + 1);
1997 tim[1] = n2 - n1 + 4;
1998 skb_put(skb, n2 - n1);
2000 *pos++ = aid0; /* Bitmap control */
2001 *pos++ = 0; /* Part Virt Bitmap */
2005 struct sk_buff *ieee80211_beacon_get(struct ieee80211_hw *hw,
2006 struct ieee80211_vif *vif)
2008 struct ieee80211_local *local = hw_to_local(hw);
2009 struct sk_buff *skb = NULL;
2010 struct ieee80211_tx_info *info;
2011 struct ieee80211_sub_if_data *sdata = NULL;
2012 struct ieee80211_if_ap *ap = NULL;
2013 struct beacon_data *beacon;
2014 struct ieee80211_supported_band *sband;
2015 enum ieee80211_band band = local->hw.conf.channel->band;
2017 sband = local->hw.wiphy->bands[band];
2021 sdata = vif_to_sdata(vif);
2023 if (sdata->vif.type == NL80211_IFTYPE_AP) {
2025 beacon = rcu_dereference(ap->beacon);
2028 * headroom, head length,
2029 * tail length and maximum TIM length
2031 skb = dev_alloc_skb(local->tx_headroom +
2033 beacon->tail_len + 256);
2037 skb_reserve(skb, local->tx_headroom);
2038 memcpy(skb_put(skb, beacon->head_len), beacon->head,
2042 * Not very nice, but we want to allow the driver to call
2043 * ieee80211_beacon_get() as a response to the set_tim()
2044 * callback. That, however, is already invoked under the
2045 * sta_lock to guarantee consistent and race-free update
2046 * of the tim bitmap in mac80211 and the driver.
2048 if (local->tim_in_locked_section) {
2049 ieee80211_beacon_add_tim(ap, skb, beacon);
2051 unsigned long flags;
2053 spin_lock_irqsave(&local->sta_lock, flags);
2054 ieee80211_beacon_add_tim(ap, skb, beacon);
2055 spin_unlock_irqrestore(&local->sta_lock, flags);
2059 memcpy(skb_put(skb, beacon->tail_len),
2060 beacon->tail, beacon->tail_len);
2063 } else if (sdata->vif.type == NL80211_IFTYPE_ADHOC) {
2064 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
2065 struct ieee80211_hdr *hdr;
2066 struct sk_buff *presp = rcu_dereference(ifibss->presp);
2071 skb = skb_copy(presp, GFP_ATOMIC);
2075 hdr = (struct ieee80211_hdr *) skb->data;
2076 hdr->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
2077 IEEE80211_STYPE_BEACON);
2078 } else if (ieee80211_vif_is_mesh(&sdata->vif)) {
2079 struct ieee80211_mgmt *mgmt;
2082 /* headroom, head length, tail length and maximum TIM length */
2083 skb = dev_alloc_skb(local->tx_headroom + 400);
2087 skb_reserve(skb, local->hw.extra_tx_headroom);
2088 mgmt = (struct ieee80211_mgmt *)
2089 skb_put(skb, 24 + sizeof(mgmt->u.beacon));
2090 memset(mgmt, 0, 24 + sizeof(mgmt->u.beacon));
2091 mgmt->frame_control =
2092 cpu_to_le16(IEEE80211_FTYPE_MGMT | IEEE80211_STYPE_BEACON);
2093 memset(mgmt->da, 0xff, ETH_ALEN);
2094 memcpy(mgmt->sa, sdata->dev->dev_addr, ETH_ALEN);
2095 /* BSSID is left zeroed, wildcard value */
2096 mgmt->u.beacon.beacon_int =
2097 cpu_to_le16(sdata->vif.bss_conf.beacon_int);
2098 mgmt->u.beacon.capab_info = 0x0; /* 0x0 for MPs */
2100 pos = skb_put(skb, 2);
2101 *pos++ = WLAN_EID_SSID;
2104 mesh_mgmt_ies_add(skb, sdata);
2110 info = IEEE80211_SKB_CB(skb);
2112 info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
2115 * XXX: For now, always use the lowest rate
2117 info->control.rates[0].idx = 0;
2118 info->control.rates[0].count = 1;
2119 info->control.rates[1].idx = -1;
2120 info->control.rates[2].idx = -1;
2121 info->control.rates[3].idx = -1;
2122 info->control.rates[4].idx = -1;
2123 BUILD_BUG_ON(IEEE80211_TX_MAX_RATES != 5);
2125 info->control.vif = vif;
2127 info->flags |= IEEE80211_TX_CTL_NO_ACK;
2128 info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT;
2129 info->flags |= IEEE80211_TX_CTL_ASSIGN_SEQ;
2134 EXPORT_SYMBOL(ieee80211_beacon_get);
2136 void ieee80211_rts_get(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
2137 const void *frame, size_t frame_len,
2138 const struct ieee80211_tx_info *frame_txctl,
2139 struct ieee80211_rts *rts)
2141 const struct ieee80211_hdr *hdr = frame;
2143 rts->frame_control =
2144 cpu_to_le16(IEEE80211_FTYPE_CTL | IEEE80211_STYPE_RTS);
2145 rts->duration = ieee80211_rts_duration(hw, vif, frame_len,
2147 memcpy(rts->ra, hdr->addr1, sizeof(rts->ra));
2148 memcpy(rts->ta, hdr->addr2, sizeof(rts->ta));
2150 EXPORT_SYMBOL(ieee80211_rts_get);
2152 void ieee80211_ctstoself_get(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
2153 const void *frame, size_t frame_len,
2154 const struct ieee80211_tx_info *frame_txctl,
2155 struct ieee80211_cts *cts)
2157 const struct ieee80211_hdr *hdr = frame;
2159 cts->frame_control =
2160 cpu_to_le16(IEEE80211_FTYPE_CTL | IEEE80211_STYPE_CTS);
2161 cts->duration = ieee80211_ctstoself_duration(hw, vif,
2162 frame_len, frame_txctl);
2163 memcpy(cts->ra, hdr->addr1, sizeof(cts->ra));
2165 EXPORT_SYMBOL(ieee80211_ctstoself_get);
2168 ieee80211_get_buffered_bc(struct ieee80211_hw *hw,
2169 struct ieee80211_vif *vif)
2171 struct ieee80211_local *local = hw_to_local(hw);
2172 struct sk_buff *skb = NULL;
2173 struct sta_info *sta;
2174 struct ieee80211_tx_data tx;
2175 struct ieee80211_sub_if_data *sdata;
2176 struct ieee80211_if_ap *bss = NULL;
2177 struct beacon_data *beacon;
2178 struct ieee80211_tx_info *info;
2180 sdata = vif_to_sdata(vif);
2184 beacon = rcu_dereference(bss->beacon);
2186 if (sdata->vif.type != NL80211_IFTYPE_AP || !beacon || !beacon->head)
2189 if (bss->dtim_count != 0)
2190 goto out; /* send buffered bc/mc only after DTIM beacon */
2193 skb = skb_dequeue(&bss->ps_bc_buf);
2196 local->total_ps_buffered--;
2198 if (!skb_queue_empty(&bss->ps_bc_buf) && skb->len >= 2) {
2199 struct ieee80211_hdr *hdr =
2200 (struct ieee80211_hdr *) skb->data;
2201 /* more buffered multicast/broadcast frames ==> set
2202 * MoreData flag in IEEE 802.11 header to inform PS
2204 hdr->frame_control |=
2205 cpu_to_le16(IEEE80211_FCTL_MOREDATA);
2208 if (!ieee80211_tx_prepare(sdata, &tx, skb))
2210 dev_kfree_skb_any(skb);
2213 info = IEEE80211_SKB_CB(skb);
2216 tx.flags |= IEEE80211_TX_PS_BUFFERED;
2217 tx.channel = local->hw.conf.channel;
2218 info->band = tx.channel->band;
2220 if (invoke_tx_handlers(&tx))
2227 EXPORT_SYMBOL(ieee80211_get_buffered_bc);
2229 void ieee80211_tx_skb(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb,
2232 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
2233 skb_set_mac_header(skb, 0);
2234 skb_set_network_header(skb, 0);
2235 skb_set_transport_header(skb, 0);
2237 skb->iif = sdata->dev->ifindex;
2239 info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
2242 * The other path calling ieee80211_xmit is from the tasklet,
2243 * and while we can handle concurrent transmissions locking
2244 * requirements are that we do not come into tx with bhs on.
2247 ieee80211_xmit(sdata, skb);