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 /* buffered in hardware */
321 if (!(tx->local->hw.flags & IEEE80211_HW_HOST_BROADCAST_PS_BUFFERING)) {
322 info->flags |= IEEE80211_TX_CTL_SEND_AFTER_DTIM;
327 /* buffered in mac80211 */
328 if (tx->local->total_ps_buffered >= TOTAL_MAX_TX_BUFFER)
329 purge_old_ps_buffers(tx->local);
331 if (skb_queue_len(&tx->sdata->bss->ps_bc_buf) >= AP_MAX_BC_BUFFER) {
332 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
334 printk(KERN_DEBUG "%s: BC TX buffer full - dropping the oldest frame\n",
337 dev_kfree_skb(skb_dequeue(&tx->sdata->bss->ps_bc_buf));
339 tx->local->total_ps_buffered++;
341 skb_queue_tail(&tx->sdata->bss->ps_bc_buf, tx->skb);
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)
371 || ieee80211_is_auth(hdr->frame_control)
372 || ieee80211_is_assoc_resp(hdr->frame_control)
373 || ieee80211_is_reassoc_resp(hdr->frame_control)))
376 staflags = get_sta_flags(sta);
378 if (unlikely((staflags & WLAN_STA_PS) &&
379 !(info->flags & IEEE80211_TX_CTL_PSPOLL_RESPONSE))) {
380 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
381 printk(KERN_DEBUG "STA %pM aid %d: PS buffer (entries "
383 sta->sta.addr, sta->sta.aid,
384 skb_queue_len(&sta->ps_tx_buf));
385 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
386 if (tx->local->total_ps_buffered >= TOTAL_MAX_TX_BUFFER)
387 purge_old_ps_buffers(tx->local);
388 if (skb_queue_len(&sta->ps_tx_buf) >= STA_MAX_TX_BUFFER) {
389 struct sk_buff *old = skb_dequeue(&sta->ps_tx_buf);
390 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
391 if (net_ratelimit()) {
392 printk(KERN_DEBUG "%s: STA %pM TX "
393 "buffer full - dropping oldest frame\n",
394 tx->dev->name, sta->sta.addr);
399 tx->local->total_ps_buffered++;
401 /* Queue frame to be sent after STA sends an PS Poll frame */
402 if (skb_queue_empty(&sta->ps_tx_buf))
403 sta_info_set_tim_bit(sta);
405 info->control.jiffies = jiffies;
406 info->control.vif = &tx->sdata->vif;
407 info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
408 skb_queue_tail(&sta->ps_tx_buf, tx->skb);
411 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
412 else if (unlikely(test_sta_flags(sta, WLAN_STA_PS))) {
413 printk(KERN_DEBUG "%s: STA %pM in PS mode, but pspoll "
414 "set -> send frame\n", tx->dev->name,
417 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
422 static ieee80211_tx_result debug_noinline
423 ieee80211_tx_h_ps_buf(struct ieee80211_tx_data *tx)
425 if (unlikely(tx->flags & IEEE80211_TX_PS_BUFFERED))
428 if (tx->flags & IEEE80211_TX_UNICAST)
429 return ieee80211_tx_h_unicast_ps_buf(tx);
431 return ieee80211_tx_h_multicast_ps_buf(tx);
434 static ieee80211_tx_result debug_noinline
435 ieee80211_tx_h_select_key(struct ieee80211_tx_data *tx)
437 struct ieee80211_key *key = NULL;
438 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
439 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
441 if (unlikely(info->flags & IEEE80211_TX_INTFL_DONT_ENCRYPT))
443 else if (tx->sta && (key = rcu_dereference(tx->sta->key)))
445 else if (ieee80211_is_mgmt(hdr->frame_control) &&
446 (key = rcu_dereference(tx->sdata->default_mgmt_key)))
448 else if ((key = rcu_dereference(tx->sdata->default_key)))
450 else if (tx->sdata->drop_unencrypted &&
451 (tx->skb->protocol != cpu_to_be16(ETH_P_PAE)) &&
452 !(info->flags & IEEE80211_TX_CTL_INJECTED) &&
453 (!ieee80211_is_robust_mgmt_frame(hdr) ||
454 (ieee80211_is_action(hdr->frame_control) &&
455 tx->sta && test_sta_flags(tx->sta, WLAN_STA_MFP)))) {
456 I802_DEBUG_INC(tx->local->tx_handlers_drop_unencrypted);
462 tx->key->tx_rx_count++;
463 /* TODO: add threshold stuff again */
465 switch (tx->key->conf.alg) {
467 if (ieee80211_is_auth(hdr->frame_control))
470 if (!ieee80211_is_data_present(hdr->frame_control))
474 if (!ieee80211_is_data_present(hdr->frame_control) &&
475 !ieee80211_use_mfp(hdr->frame_control, tx->sta,
480 if (!ieee80211_is_mgmt(hdr->frame_control))
486 if (!tx->key || !(tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))
487 info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
492 static ieee80211_tx_result debug_noinline
493 ieee80211_tx_h_rate_ctrl(struct ieee80211_tx_data *tx)
495 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
496 struct ieee80211_hdr *hdr = (void *)tx->skb->data;
497 struct ieee80211_supported_band *sband;
498 struct ieee80211_rate *rate;
501 bool inval = false, rts = false, short_preamble = false;
502 struct ieee80211_tx_rate_control txrc;
505 memset(&txrc, 0, sizeof(txrc));
507 sband = tx->local->hw.wiphy->bands[tx->channel->band];
509 len = min_t(u32, tx->skb->len + FCS_LEN,
510 tx->local->hw.wiphy->frag_threshold);
512 /* set up the tx rate control struct we give the RC algo */
513 txrc.hw = local_to_hw(tx->local);
515 txrc.bss_conf = &tx->sdata->vif.bss_conf;
517 txrc.reported_rate.idx = -1;
518 txrc.max_rate_idx = tx->sdata->max_ratectrl_rateidx;
520 /* set up RTS protection if desired */
521 if (len > tx->local->hw.wiphy->rts_threshold) {
522 txrc.rts = rts = true;
526 * Use short preamble if the BSS can handle it, but not for
527 * management frames unless we know the receiver can handle
528 * that -- the management frame might be to a station that
529 * just wants a probe response.
531 if (tx->sdata->vif.bss_conf.use_short_preamble &&
532 (ieee80211_is_data(hdr->frame_control) ||
533 (tx->sta && test_sta_flags(tx->sta, WLAN_STA_SHORT_PREAMBLE))))
534 txrc.short_preamble = short_preamble = true;
536 sta_flags = tx->sta ? get_sta_flags(tx->sta) : 0;
539 * Lets not bother rate control if we're associated and cannot
540 * talk to the sta. This should not happen.
542 if (WARN(test_bit(SCAN_SW_SCANNING, &tx->local->scanning) &&
543 (sta_flags & WLAN_STA_ASSOC) &&
544 !rate_usable_index_exists(sband, &tx->sta->sta),
545 "%s: Dropped data frame as no usable bitrate found while "
546 "scanning and associated. Target station: "
547 "%pM on %d GHz band\n",
548 tx->dev->name, hdr->addr1,
549 tx->channel->band ? 5 : 2))
553 * If we're associated with the sta at this point we know we can at
554 * least send the frame at the lowest bit rate.
556 rate_control_get_rate(tx->sdata, tx->sta, &txrc);
558 if (unlikely(info->control.rates[0].idx < 0))
561 if (txrc.reported_rate.idx < 0)
562 txrc.reported_rate = info->control.rates[0];
565 tx->sta->last_tx_rate = txrc.reported_rate;
567 if (unlikely(!info->control.rates[0].count))
568 info->control.rates[0].count = 1;
570 if (WARN_ON_ONCE((info->control.rates[0].count > 1) &&
571 (info->flags & IEEE80211_TX_CTL_NO_ACK)))
572 info->control.rates[0].count = 1;
574 if (is_multicast_ether_addr(hdr->addr1)) {
576 * XXX: verify the rate is in the basic rateset
582 * set up the RTS/CTS rate as the fastest basic rate
583 * that is not faster than the data rate
585 * XXX: Should this check all retry rates?
587 if (!(info->control.rates[0].flags & IEEE80211_TX_RC_MCS)) {
590 rate = &sband->bitrates[info->control.rates[0].idx];
592 for (i = 0; i < sband->n_bitrates; i++) {
593 /* must be a basic rate */
594 if (!(tx->sdata->vif.bss_conf.basic_rates & BIT(i)))
596 /* must not be faster than the data rate */
597 if (sband->bitrates[i].bitrate > rate->bitrate)
600 if (sband->bitrates[baserate].bitrate <
601 sband->bitrates[i].bitrate)
605 info->control.rts_cts_rate_idx = baserate;
608 for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) {
610 * make sure there's no valid rate following
611 * an invalid one, just in case drivers don't
612 * take the API seriously to stop at -1.
615 info->control.rates[i].idx = -1;
618 if (info->control.rates[i].idx < 0) {
624 * For now assume MCS is already set up correctly, this
627 if (info->control.rates[i].flags & IEEE80211_TX_RC_MCS) {
628 WARN_ON(info->control.rates[i].idx > 76);
632 /* set up RTS protection if desired */
634 info->control.rates[i].flags |=
635 IEEE80211_TX_RC_USE_RTS_CTS;
638 if (WARN_ON_ONCE(info->control.rates[i].idx >=
639 sband->n_bitrates)) {
640 info->control.rates[i].idx = -1;
644 rate = &sband->bitrates[info->control.rates[i].idx];
646 /* set up short preamble */
647 if (short_preamble &&
648 rate->flags & IEEE80211_RATE_SHORT_PREAMBLE)
649 info->control.rates[i].flags |=
650 IEEE80211_TX_RC_USE_SHORT_PREAMBLE;
652 /* set up G protection */
653 if (!rts && tx->sdata->vif.bss_conf.use_cts_prot &&
654 rate->flags & IEEE80211_RATE_ERP_G)
655 info->control.rates[i].flags |=
656 IEEE80211_TX_RC_USE_CTS_PROTECT;
662 static ieee80211_tx_result debug_noinline
663 ieee80211_tx_h_misc(struct ieee80211_tx_data *tx)
665 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
668 info->control.sta = &tx->sta->sta;
673 static ieee80211_tx_result debug_noinline
674 ieee80211_tx_h_sequence(struct ieee80211_tx_data *tx)
676 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
677 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
683 * Packet injection may want to control the sequence
684 * number, if we have no matching interface then we
685 * neither assign one ourselves nor ask the driver to.
687 if (unlikely(info->control.vif->type == NL80211_IFTYPE_MONITOR))
690 if (unlikely(ieee80211_is_ctl(hdr->frame_control)))
693 if (ieee80211_hdrlen(hdr->frame_control) < 24)
697 * Anything but QoS data that has a sequence number field
698 * (is long enough) gets a sequence number from the global
701 if (!ieee80211_is_data_qos(hdr->frame_control)) {
702 /* driver should assign sequence number */
703 info->flags |= IEEE80211_TX_CTL_ASSIGN_SEQ;
704 /* for pure STA mode without beacons, we can do it */
705 hdr->seq_ctrl = cpu_to_le16(tx->sdata->sequence_number);
706 tx->sdata->sequence_number += 0x10;
711 * This should be true for injected/management frames only, for
712 * management frames we have set the IEEE80211_TX_CTL_ASSIGN_SEQ
713 * above since they are not QoS-data frames.
718 /* include per-STA, per-TID sequence counter */
720 qc = ieee80211_get_qos_ctl(hdr);
721 tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
722 seq = &tx->sta->tid_seq[tid];
724 hdr->seq_ctrl = cpu_to_le16(*seq);
726 /* Increase the sequence number. */
727 *seq = (*seq + 0x10) & IEEE80211_SCTL_SEQ;
732 static int ieee80211_fragment(struct ieee80211_local *local,
733 struct sk_buff *skb, int hdrlen,
736 struct sk_buff *tail = skb, *tmp;
737 int per_fragm = frag_threshold - hdrlen - FCS_LEN;
738 int pos = hdrlen + per_fragm;
739 int rem = skb->len - hdrlen - per_fragm;
741 if (WARN_ON(rem < 0))
745 int fraglen = per_fragm;
750 tmp = dev_alloc_skb(local->tx_headroom +
752 IEEE80211_ENCRYPT_HEADROOM +
753 IEEE80211_ENCRYPT_TAILROOM);
758 skb_reserve(tmp, local->tx_headroom +
759 IEEE80211_ENCRYPT_HEADROOM);
760 /* copy control information */
761 memcpy(tmp->cb, skb->cb, sizeof(tmp->cb));
762 skb_copy_queue_mapping(tmp, skb);
763 tmp->priority = skb->priority;
766 /* copy header and data */
767 memcpy(skb_put(tmp, hdrlen), skb->data, hdrlen);
768 memcpy(skb_put(tmp, fraglen), skb->data + pos, fraglen);
773 skb->len = hdrlen + per_fragm;
777 static ieee80211_tx_result debug_noinline
778 ieee80211_tx_h_fragment(struct ieee80211_tx_data *tx)
780 struct sk_buff *skb = tx->skb;
781 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
782 struct ieee80211_hdr *hdr = (void *)skb->data;
783 int frag_threshold = tx->local->hw.wiphy->frag_threshold;
787 if (!(tx->flags & IEEE80211_TX_FRAGMENTED))
791 * Warn when submitting a fragmented A-MPDU frame and drop it.
792 * This scenario is handled in ieee80211_tx_prepare but extra
793 * caution taken here as fragmented ampdu may cause Tx stop.
795 if (WARN_ON(info->flags & IEEE80211_TX_CTL_AMPDU))
798 hdrlen = ieee80211_hdrlen(hdr->frame_control);
800 /* internal error, why is TX_FRAGMENTED set? */
801 if (WARN_ON(skb->len + FCS_LEN <= frag_threshold))
805 * Now fragment the frame. This will allocate all the fragments and
806 * chain them (using skb as the first fragment) to skb->next.
807 * During transmission, we will remove the successfully transmitted
808 * fragments from this list. When the low-level driver rejects one
809 * of the fragments then we will simply pretend to accept the skb
810 * but store it away as pending.
812 if (ieee80211_fragment(tx->local, skb, hdrlen, frag_threshold))
815 /* update duration/seq/flags of fragments */
819 const __le16 morefrags = cpu_to_le16(IEEE80211_FCTL_MOREFRAGS);
821 hdr = (void *)skb->data;
822 info = IEEE80211_SKB_CB(skb);
825 hdr->frame_control |= morefrags;
826 next_len = skb->next->len;
828 * No multi-rate retries for fragmented frames, that
829 * would completely throw off the NAV at other STAs.
831 info->control.rates[1].idx = -1;
832 info->control.rates[2].idx = -1;
833 info->control.rates[3].idx = -1;
834 info->control.rates[4].idx = -1;
835 BUILD_BUG_ON(IEEE80211_TX_MAX_RATES != 5);
836 info->flags &= ~IEEE80211_TX_CTL_RATE_CTRL_PROBE;
838 hdr->frame_control &= ~morefrags;
841 hdr->duration_id = ieee80211_duration(tx, 0, next_len);
842 hdr->seq_ctrl |= cpu_to_le16(fragnum & IEEE80211_SCTL_FRAG);
844 } while ((skb = skb->next));
849 static ieee80211_tx_result debug_noinline
850 ieee80211_tx_h_stats(struct ieee80211_tx_data *tx)
852 struct sk_buff *skb = tx->skb;
857 tx->sta->tx_packets++;
859 tx->sta->tx_fragments++;
860 tx->sta->tx_bytes += skb->len;
861 } while ((skb = skb->next));
866 static ieee80211_tx_result debug_noinline
867 ieee80211_tx_h_encrypt(struct ieee80211_tx_data *tx)
872 switch (tx->key->conf.alg) {
874 return ieee80211_crypto_wep_encrypt(tx);
876 return ieee80211_crypto_tkip_encrypt(tx);
878 return ieee80211_crypto_ccmp_encrypt(tx);
880 return ieee80211_crypto_aes_cmac_encrypt(tx);
888 static ieee80211_tx_result debug_noinline
889 ieee80211_tx_h_calculate_duration(struct ieee80211_tx_data *tx)
891 struct sk_buff *skb = tx->skb;
892 struct ieee80211_hdr *hdr;
897 hdr = (void *) skb->data;
898 if (unlikely(ieee80211_is_pspoll(hdr->frame_control)))
899 break; /* must not overwrite AID */
900 next_len = skb->next ? skb->next->len : 0;
901 group_addr = is_multicast_ether_addr(hdr->addr1);
904 ieee80211_duration(tx, group_addr, next_len);
905 } while ((skb = skb->next));
910 /* actual transmit path */
913 * deal with packet injection down monitor interface
914 * with Radiotap Header -- only called for monitor mode interface
916 static bool __ieee80211_parse_tx_radiotap(struct ieee80211_tx_data *tx,
920 * this is the moment to interpret and discard the radiotap header that
921 * must be at the start of the packet injected in Monitor mode
923 * Need to take some care with endian-ness since radiotap
924 * args are little-endian
927 struct ieee80211_radiotap_iterator iterator;
928 struct ieee80211_radiotap_header *rthdr =
929 (struct ieee80211_radiotap_header *) skb->data;
930 struct ieee80211_supported_band *sband;
931 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
932 int ret = ieee80211_radiotap_iterator_init(&iterator, rthdr, skb->len);
934 sband = tx->local->hw.wiphy->bands[tx->channel->band];
936 info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
937 tx->flags &= ~IEEE80211_TX_FRAGMENTED;
940 * for every radiotap entry that is present
941 * (ieee80211_radiotap_iterator_next returns -ENOENT when no more
942 * entries present, or -EINVAL on error)
946 ret = ieee80211_radiotap_iterator_next(&iterator);
951 /* see if this argument is something we can use */
952 switch (iterator.this_arg_index) {
954 * You must take care when dereferencing iterator.this_arg
955 * for multibyte types... the pointer is not aligned. Use
956 * get_unaligned((type *)iterator.this_arg) to dereference
957 * iterator.this_arg for type "type" safely on all arches.
959 case IEEE80211_RADIOTAP_FLAGS:
960 if (*iterator.this_arg & IEEE80211_RADIOTAP_F_FCS) {
962 * this indicates that the skb we have been
963 * handed has the 32-bit FCS CRC at the end...
964 * we should react to that by snipping it off
965 * because it will be recomputed and added
968 if (skb->len < (iterator.max_length + FCS_LEN))
971 skb_trim(skb, skb->len - FCS_LEN);
973 if (*iterator.this_arg & IEEE80211_RADIOTAP_F_WEP)
974 info->flags &= ~IEEE80211_TX_INTFL_DONT_ENCRYPT;
975 if (*iterator.this_arg & IEEE80211_RADIOTAP_F_FRAG)
976 tx->flags |= IEEE80211_TX_FRAGMENTED;
980 * Please update the file
981 * Documentation/networking/mac80211-injection.txt
982 * when parsing new fields here.
990 if (ret != -ENOENT) /* ie, if we didn't simply run out of fields */
994 * remove the radiotap header
995 * iterator->max_length was sanity-checked against
996 * skb->len by iterator init
998 skb_pull(skb, iterator.max_length);
1006 static ieee80211_tx_result
1007 ieee80211_tx_prepare(struct ieee80211_sub_if_data *sdata,
1008 struct ieee80211_tx_data *tx,
1009 struct sk_buff *skb)
1011 struct ieee80211_local *local = sdata->local;
1012 struct ieee80211_hdr *hdr;
1013 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1016 bool queued = false;
1018 memset(tx, 0, sizeof(*tx));
1020 tx->dev = sdata->dev; /* use original interface */
1023 tx->channel = local->hw.conf.channel;
1025 * Set this flag (used below to indicate "automatic fragmentation"),
1026 * it will be cleared/left by radiotap as desired.
1028 tx->flags |= IEEE80211_TX_FRAGMENTED;
1030 /* process and remove the injection radiotap header */
1031 if (unlikely(info->flags & IEEE80211_TX_CTL_INJECTED)) {
1032 if (!__ieee80211_parse_tx_radiotap(tx, skb))
1036 * __ieee80211_parse_tx_radiotap has now removed
1037 * the radiotap header that was present and pre-filled
1038 * 'tx' with tx control information.
1043 * If this flag is set to true anywhere, and we get here,
1044 * we are doing the needed processing, so remove the flag
1047 info->flags &= ~IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1049 hdr = (struct ieee80211_hdr *) skb->data;
1051 tx->sta = sta_info_get(local, hdr->addr1);
1053 if (tx->sta && ieee80211_is_data_qos(hdr->frame_control) &&
1054 (local->hw.flags & IEEE80211_HW_AMPDU_AGGREGATION)) {
1055 unsigned long flags;
1056 struct tid_ampdu_tx *tid_tx;
1058 qc = ieee80211_get_qos_ctl(hdr);
1059 tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
1061 spin_lock_irqsave(&tx->sta->lock, flags);
1063 * XXX: This spinlock could be fairly expensive, but see the
1064 * comment in agg-tx.c:ieee80211_agg_tx_operational().
1065 * One way to solve this would be to do something RCU-like
1066 * for managing the tid_tx struct and using atomic bitops
1067 * for the actual state -- by introducing an actual
1068 * 'operational' bit that would be possible. It would
1069 * require changing ieee80211_agg_tx_operational() to
1070 * set that bit, and changing the way tid_tx is managed
1071 * everywhere, including races between that bit and
1072 * tid_tx going away (tid_tx being added can be easily
1073 * committed to memory before the 'operational' bit).
1075 tid_tx = tx->sta->ampdu_mlme.tid_tx[tid];
1076 state = &tx->sta->ampdu_mlme.tid_state_tx[tid];
1077 if (*state == HT_AGG_STATE_OPERATIONAL) {
1078 info->flags |= IEEE80211_TX_CTL_AMPDU;
1079 } else if (*state != HT_AGG_STATE_IDLE) {
1082 info->control.vif = &sdata->vif;
1083 info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1084 __skb_queue_tail(&tid_tx->pending, skb);
1086 spin_unlock_irqrestore(&tx->sta->lock, flags);
1088 if (unlikely(queued))
1092 if (is_multicast_ether_addr(hdr->addr1)) {
1093 tx->flags &= ~IEEE80211_TX_UNICAST;
1094 info->flags |= IEEE80211_TX_CTL_NO_ACK;
1096 tx->flags |= IEEE80211_TX_UNICAST;
1097 if (unlikely(local->wifi_wme_noack_test))
1098 info->flags |= IEEE80211_TX_CTL_NO_ACK;
1100 info->flags &= ~IEEE80211_TX_CTL_NO_ACK;
1103 if (tx->flags & IEEE80211_TX_FRAGMENTED) {
1104 if ((tx->flags & IEEE80211_TX_UNICAST) &&
1105 skb->len + FCS_LEN > local->hw.wiphy->frag_threshold &&
1106 !(info->flags & IEEE80211_TX_CTL_AMPDU))
1107 tx->flags |= IEEE80211_TX_FRAGMENTED;
1109 tx->flags &= ~IEEE80211_TX_FRAGMENTED;
1113 info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT;
1114 else if (test_and_clear_sta_flags(tx->sta, WLAN_STA_CLEAR_PS_FILT))
1115 info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT;
1117 hdrlen = ieee80211_hdrlen(hdr->frame_control);
1118 if (skb->len > hdrlen + sizeof(rfc1042_header) + 2) {
1119 u8 *pos = &skb->data[hdrlen + sizeof(rfc1042_header)];
1120 tx->ethertype = (pos[0] << 8) | pos[1];
1122 info->flags |= IEEE80211_TX_CTL_FIRST_FRAGMENT;
1127 static int __ieee80211_tx(struct ieee80211_local *local,
1128 struct sk_buff **skbp,
1129 struct sta_info *sta,
1132 struct sk_buff *skb = *skbp, *next;
1133 struct ieee80211_tx_info *info;
1134 struct ieee80211_sub_if_data *sdata;
1135 unsigned long flags;
1140 int q = skb_get_queue_mapping(skb);
1142 spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
1143 ret = IEEE80211_TX_OK;
1144 if (local->queue_stop_reasons[q] ||
1145 (!txpending && !skb_queue_empty(&local->pending[q])))
1146 ret = IEEE80211_TX_PENDING;
1147 spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
1148 if (ret != IEEE80211_TX_OK)
1151 info = IEEE80211_SKB_CB(skb);
1154 info->flags &= ~(IEEE80211_TX_CTL_CLEAR_PS_FILT |
1155 IEEE80211_TX_CTL_FIRST_FRAGMENT);
1161 info->flags |= IEEE80211_TX_CTL_MORE_FRAMES;
1163 sdata = vif_to_sdata(info->control.vif);
1165 switch (sdata->vif.type) {
1166 case NL80211_IFTYPE_MONITOR:
1167 info->control.vif = NULL;
1169 case NL80211_IFTYPE_AP_VLAN:
1170 info->control.vif = &container_of(sdata->bss,
1171 struct ieee80211_sub_if_data, u.ap)->vif;
1178 ret = drv_tx(local, skb);
1179 if (WARN_ON(ret != NETDEV_TX_OK && skb->len != len)) {
1183 if (ret != NETDEV_TX_OK) {
1184 info->control.vif = &sdata->vif;
1185 return IEEE80211_TX_AGAIN;
1189 ieee80211_led_tx(local, 1);
1193 return IEEE80211_TX_OK;
1197 * Invoke TX handlers, return 0 on success and non-zero if the
1198 * frame was dropped or queued.
1200 static int invoke_tx_handlers(struct ieee80211_tx_data *tx)
1202 struct sk_buff *skb = tx->skb;
1203 ieee80211_tx_result res = TX_DROP;
1205 #define CALL_TXH(txh) \
1207 if (res != TX_CONTINUE) \
1210 CALL_TXH(ieee80211_tx_h_check_assoc)
1211 CALL_TXH(ieee80211_tx_h_ps_buf)
1212 CALL_TXH(ieee80211_tx_h_select_key)
1213 CALL_TXH(ieee80211_tx_h_michael_mic_add)
1214 CALL_TXH(ieee80211_tx_h_rate_ctrl)
1215 CALL_TXH(ieee80211_tx_h_misc)
1216 CALL_TXH(ieee80211_tx_h_sequence)
1217 CALL_TXH(ieee80211_tx_h_fragment)
1218 /* handlers after fragment must be aware of tx info fragmentation! */
1219 CALL_TXH(ieee80211_tx_h_stats)
1220 CALL_TXH(ieee80211_tx_h_encrypt)
1221 CALL_TXH(ieee80211_tx_h_calculate_duration)
1225 if (unlikely(res == TX_DROP)) {
1226 I802_DEBUG_INC(tx->local->tx_handlers_drop);
1228 struct sk_buff *next;
1235 } else if (unlikely(res == TX_QUEUED)) {
1236 I802_DEBUG_INC(tx->local->tx_handlers_queued);
1243 static void ieee80211_tx(struct ieee80211_sub_if_data *sdata,
1244 struct sk_buff *skb, bool txpending)
1246 struct ieee80211_local *local = sdata->local;
1247 struct ieee80211_tx_data tx;
1248 ieee80211_tx_result res_prepare;
1249 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1250 struct sk_buff *next;
1251 unsigned long flags;
1255 queue = skb_get_queue_mapping(skb);
1257 if (unlikely(skb->len < 10)) {
1264 /* initialises tx */
1265 res_prepare = ieee80211_tx_prepare(sdata, &tx, skb);
1267 if (unlikely(res_prepare == TX_DROP)) {
1271 } else if (unlikely(res_prepare == TX_QUEUED)) {
1276 tx.channel = local->hw.conf.channel;
1277 info->band = tx.channel->band;
1279 if (invoke_tx_handlers(&tx))
1284 ret = __ieee80211_tx(local, &tx.skb, tx.sta, txpending);
1286 case IEEE80211_TX_OK:
1288 case IEEE80211_TX_AGAIN:
1290 * Since there are no fragmented frames on A-MPDU
1291 * queues, there's no reason for a driver to reject
1292 * a frame there, warn and drop it.
1294 if (WARN_ON(info->flags & IEEE80211_TX_CTL_AMPDU))
1297 case IEEE80211_TX_PENDING:
1300 spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
1302 if (local->queue_stop_reasons[queue] ||
1303 !skb_queue_empty(&local->pending[queue])) {
1305 * if queue is stopped, queue up frames for later
1306 * transmission from the tasklet
1311 if (unlikely(txpending))
1312 __skb_queue_head(&local->pending[queue],
1315 __skb_queue_tail(&local->pending[queue],
1317 } while ((skb = next));
1319 spin_unlock_irqrestore(&local->queue_stop_reason_lock,
1323 * otherwise retry, but this is a race condition or
1324 * a driver bug (which we warn about if it persists)
1326 spin_unlock_irqrestore(&local->queue_stop_reason_lock,
1330 if (WARN(retries > 10, "tx refused but queue active\n"))
1350 /* device xmit handlers */
1352 static int ieee80211_skb_resize(struct ieee80211_local *local,
1353 struct sk_buff *skb,
1354 int head_need, bool may_encrypt)
1359 * This could be optimised, devices that do full hardware
1360 * crypto (including TKIP MMIC) need no tailroom... But we
1361 * have no drivers for such devices currently.
1364 tail_need = IEEE80211_ENCRYPT_TAILROOM;
1365 tail_need -= skb_tailroom(skb);
1366 tail_need = max_t(int, tail_need, 0);
1369 if (head_need || tail_need) {
1370 /* Sorry. Can't account for this any more */
1374 if (skb_header_cloned(skb))
1375 I802_DEBUG_INC(local->tx_expand_skb_head_cloned);
1377 I802_DEBUG_INC(local->tx_expand_skb_head);
1379 if (pskb_expand_head(skb, head_need, tail_need, GFP_ATOMIC)) {
1380 printk(KERN_DEBUG "%s: failed to reallocate TX buffer\n",
1381 wiphy_name(local->hw.wiphy));
1385 /* update truesize too */
1386 skb->truesize += head_need + tail_need;
1391 static void ieee80211_xmit(struct ieee80211_sub_if_data *sdata,
1392 struct sk_buff *skb)
1394 struct ieee80211_local *local = sdata->local;
1395 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1396 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1397 struct ieee80211_sub_if_data *tmp_sdata;
1401 dev_hold(sdata->dev);
1403 if ((local->hw.flags & IEEE80211_HW_PS_NULLFUNC_STACK) &&
1404 local->hw.conf.dynamic_ps_timeout > 0 &&
1405 !local->quiescing &&
1406 !(local->scanning) && local->ps_sdata) {
1407 if (local->hw.conf.flags & IEEE80211_CONF_PS) {
1408 ieee80211_stop_queues_by_reason(&local->hw,
1409 IEEE80211_QUEUE_STOP_REASON_PS);
1410 ieee80211_queue_work(&local->hw,
1411 &local->dynamic_ps_disable_work);
1414 mod_timer(&local->dynamic_ps_timer, jiffies +
1415 msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout));
1418 info->flags |= IEEE80211_TX_CTL_REQ_TX_STATUS;
1420 if (unlikely(sdata->vif.type == NL80211_IFTYPE_MONITOR)) {
1424 info->flags |= IEEE80211_TX_CTL_INJECTED;
1426 len_rthdr = ieee80211_get_radiotap_len(skb->data);
1427 hdr = (struct ieee80211_hdr *)(skb->data + len_rthdr);
1428 hdrlen = ieee80211_hdrlen(hdr->frame_control);
1430 /* check the header is complete in the frame */
1431 if (likely(skb->len >= len_rthdr + hdrlen)) {
1433 * We process outgoing injected frames that have a
1434 * local address we handle as though they are our
1436 * This code here isn't entirely correct, the local
1437 * MAC address is not necessarily enough to find
1438 * the interface to use; for that proper VLAN/WDS
1439 * support we will need a different mechanism.
1443 list_for_each_entry_rcu(tmp_sdata, &local->interfaces,
1445 if (!netif_running(tmp_sdata->dev))
1447 if (tmp_sdata->vif.type != NL80211_IFTYPE_AP)
1449 if (compare_ether_addr(tmp_sdata->dev->dev_addr,
1451 dev_hold(tmp_sdata->dev);
1452 dev_put(sdata->dev);
1461 may_encrypt = !(info->flags & IEEE80211_TX_INTFL_DONT_ENCRYPT);
1463 headroom = local->tx_headroom;
1465 headroom += IEEE80211_ENCRYPT_HEADROOM;
1466 headroom -= skb_headroom(skb);
1467 headroom = max_t(int, 0, headroom);
1469 if (ieee80211_skb_resize(local, skb, headroom, may_encrypt)) {
1471 dev_put(sdata->dev);
1475 info->control.vif = &sdata->vif;
1477 if (ieee80211_vif_is_mesh(&sdata->vif) &&
1478 ieee80211_is_data(hdr->frame_control) &&
1479 !is_multicast_ether_addr(hdr->addr1))
1480 if (mesh_nexthop_lookup(skb, sdata)) {
1481 /* skb queued: don't free */
1482 dev_put(sdata->dev);
1486 ieee80211_set_qos_hdr(local, skb);
1487 ieee80211_tx(sdata, skb, false);
1488 dev_put(sdata->dev);
1491 netdev_tx_t ieee80211_monitor_start_xmit(struct sk_buff *skb,
1492 struct net_device *dev)
1494 struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
1495 struct ieee80211_channel *chan = local->hw.conf.channel;
1496 struct ieee80211_radiotap_header *prthdr =
1497 (struct ieee80211_radiotap_header *)skb->data;
1498 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1502 * Frame injection is not allowed if beaconing is not allowed
1503 * or if we need radar detection. Beaconing is usually not allowed when
1504 * the mode or operation (Adhoc, AP, Mesh) does not support DFS.
1505 * Passive scan is also used in world regulatory domains where
1506 * your country is not known and as such it should be treated as
1507 * NO TX unless the channel is explicitly allowed in which case
1508 * your current regulatory domain would not have the passive scan
1511 * Since AP mode uses monitor interfaces to inject/TX management
1512 * frames we can make AP mode the exception to this rule once it
1513 * supports radar detection as its implementation can deal with
1514 * radar detection by itself. We can do that later by adding a
1515 * monitor flag interfaces used for AP support.
1517 if ((chan->flags & (IEEE80211_CHAN_NO_IBSS | IEEE80211_CHAN_RADAR |
1518 IEEE80211_CHAN_PASSIVE_SCAN)))
1521 /* check for not even having the fixed radiotap header part */
1522 if (unlikely(skb->len < sizeof(struct ieee80211_radiotap_header)))
1523 goto fail; /* too short to be possibly valid */
1525 /* is it a header version we can trust to find length from? */
1526 if (unlikely(prthdr->it_version))
1527 goto fail; /* only version 0 is supported */
1529 /* then there must be a radiotap header with a length we can use */
1530 len_rthdr = ieee80211_get_radiotap_len(skb->data);
1532 /* does the skb contain enough to deliver on the alleged length? */
1533 if (unlikely(skb->len < len_rthdr))
1534 goto fail; /* skb too short for claimed rt header extent */
1537 * fix up the pointers accounting for the radiotap
1538 * header still being in there. We are being given
1539 * a precooked IEEE80211 header so no need for
1542 skb_set_mac_header(skb, len_rthdr);
1544 * these are just fixed to the end of the rt area since we
1545 * don't have any better information and at this point, nobody cares
1547 skb_set_network_header(skb, len_rthdr);
1548 skb_set_transport_header(skb, len_rthdr);
1550 memset(info, 0, sizeof(*info));
1552 /* pass the radiotap header up to xmit */
1553 ieee80211_xmit(IEEE80211_DEV_TO_SUB_IF(dev), skb);
1554 return NETDEV_TX_OK;
1558 return NETDEV_TX_OK; /* meaning, we dealt with the skb */
1562 * ieee80211_subif_start_xmit - netif start_xmit function for Ethernet-type
1563 * subinterfaces (wlan#, WDS, and VLAN interfaces)
1564 * @skb: packet to be sent
1565 * @dev: incoming interface
1567 * Returns: 0 on success (and frees skb in this case) or 1 on failure (skb will
1568 * not be freed, and caller is responsible for either retrying later or freeing
1571 * This function takes in an Ethernet header and encapsulates it with suitable
1572 * IEEE 802.11 header based on which interface the packet is coming in. The
1573 * encapsulated packet will then be passed to master interface, wlan#.11, for
1574 * transmission (through low-level driver).
1576 netdev_tx_t ieee80211_subif_start_xmit(struct sk_buff *skb,
1577 struct net_device *dev)
1579 struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1580 struct ieee80211_local *local = sdata->local;
1581 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1582 int ret = NETDEV_TX_BUSY, head_need;
1583 u16 ethertype, hdrlen, meshhdrlen = 0;
1585 struct ieee80211_hdr hdr;
1586 struct ieee80211s_hdr mesh_hdr;
1587 const u8 *encaps_data;
1588 int encaps_len, skip_header_bytes;
1590 struct sta_info *sta;
1593 if (unlikely(skb->len < ETH_HLEN)) {
1598 nh_pos = skb_network_header(skb) - skb->data;
1599 h_pos = skb_transport_header(skb) - skb->data;
1601 /* convert Ethernet header to proper 802.11 header (based on
1602 * operation mode) */
1603 ethertype = (skb->data[12] << 8) | skb->data[13];
1604 fc = cpu_to_le16(IEEE80211_FTYPE_DATA | IEEE80211_STYPE_DATA);
1606 switch (sdata->vif.type) {
1607 case NL80211_IFTYPE_AP:
1608 case NL80211_IFTYPE_AP_VLAN:
1609 fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS);
1611 memcpy(hdr.addr1, skb->data, ETH_ALEN);
1612 memcpy(hdr.addr2, dev->dev_addr, ETH_ALEN);
1613 memcpy(hdr.addr3, skb->data + ETH_ALEN, ETH_ALEN);
1616 case NL80211_IFTYPE_WDS:
1617 fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS);
1619 memcpy(hdr.addr1, sdata->u.wds.remote_addr, ETH_ALEN);
1620 memcpy(hdr.addr2, dev->dev_addr, ETH_ALEN);
1621 memcpy(hdr.addr3, skb->data, ETH_ALEN);
1622 memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN);
1625 #ifdef CONFIG_MAC80211_MESH
1626 case NL80211_IFTYPE_MESH_POINT:
1627 if (!sdata->u.mesh.mshcfg.dot11MeshTTL) {
1628 /* Do not send frames with mesh_ttl == 0 */
1629 sdata->u.mesh.mshstats.dropped_frames_ttl++;
1634 if (compare_ether_addr(dev->dev_addr,
1635 skb->data + ETH_ALEN) == 0) {
1636 hdrlen = ieee80211_fill_mesh_addresses(&hdr, &fc,
1637 skb->data, skb->data + ETH_ALEN);
1638 meshhdrlen = ieee80211_new_mesh_header(&mesh_hdr,
1639 sdata, NULL, NULL, NULL);
1641 /* packet from other interface */
1642 struct mesh_path *mppath;
1643 int is_mesh_mcast = 1;
1647 if (is_multicast_ether_addr(skb->data))
1648 /* DA TA mSA AE:SA */
1649 mesh_da = skb->data;
1651 mppath = mpp_path_lookup(skb->data, sdata);
1653 /* RA TA mDA mSA AE:DA SA */
1654 mesh_da = mppath->mpp;
1657 /* DA TA mSA AE:SA */
1658 mesh_da = dev->broadcast;
1660 hdrlen = ieee80211_fill_mesh_addresses(&hdr, &fc,
1661 mesh_da, dev->dev_addr);
1665 ieee80211_new_mesh_header(&mesh_hdr,
1667 skb->data + ETH_ALEN,
1672 ieee80211_new_mesh_header(&mesh_hdr,
1676 skb->data + ETH_ALEN);
1681 case NL80211_IFTYPE_STATION:
1682 fc |= cpu_to_le16(IEEE80211_FCTL_TODS);
1684 memcpy(hdr.addr1, sdata->u.mgd.bssid, ETH_ALEN);
1685 memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
1686 memcpy(hdr.addr3, skb->data, ETH_ALEN);
1689 case NL80211_IFTYPE_ADHOC:
1691 memcpy(hdr.addr1, skb->data, ETH_ALEN);
1692 memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
1693 memcpy(hdr.addr3, sdata->u.ibss.bssid, ETH_ALEN);
1702 * There's no need to try to look up the destination
1703 * if it is a multicast address (which can only happen
1706 if (!is_multicast_ether_addr(hdr.addr1)) {
1708 sta = sta_info_get(local, hdr.addr1);
1709 /* XXX: in the future, use sdata to look up the sta */
1710 if (sta && sta->sdata == sdata)
1711 sta_flags = get_sta_flags(sta);
1715 /* receiver and we are QoS enabled, use a QoS type frame */
1716 if ((sta_flags & WLAN_STA_WME) && local->hw.queues >= 4) {
1717 fc |= cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
1722 * Drop unicast frames to unauthorised stations unless they are
1723 * EAPOL frames from the local station.
1725 if (!ieee80211_vif_is_mesh(&sdata->vif) &&
1726 unlikely(!is_multicast_ether_addr(hdr.addr1) &&
1727 !(sta_flags & WLAN_STA_AUTHORIZED) &&
1728 !(ethertype == ETH_P_PAE &&
1729 compare_ether_addr(dev->dev_addr,
1730 skb->data + ETH_ALEN) == 0))) {
1731 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
1732 if (net_ratelimit())
1733 printk(KERN_DEBUG "%s: dropped frame to %pM"
1734 " (unauthorized port)\n", dev->name,
1738 I802_DEBUG_INC(local->tx_handlers_drop_unauth_port);
1744 hdr.frame_control = fc;
1745 hdr.duration_id = 0;
1748 skip_header_bytes = ETH_HLEN;
1749 if (ethertype == ETH_P_AARP || ethertype == ETH_P_IPX) {
1750 encaps_data = bridge_tunnel_header;
1751 encaps_len = sizeof(bridge_tunnel_header);
1752 skip_header_bytes -= 2;
1753 } else if (ethertype >= 0x600) {
1754 encaps_data = rfc1042_header;
1755 encaps_len = sizeof(rfc1042_header);
1756 skip_header_bytes -= 2;
1762 skb_pull(skb, skip_header_bytes);
1763 nh_pos -= skip_header_bytes;
1764 h_pos -= skip_header_bytes;
1766 head_need = hdrlen + encaps_len + meshhdrlen - skb_headroom(skb);
1769 * So we need to modify the skb header and hence need a copy of
1770 * that. The head_need variable above doesn't, so far, include
1771 * the needed header space that we don't need right away. If we
1772 * can, then we don't reallocate right now but only after the
1773 * frame arrives at the master device (if it does...)
1775 * If we cannot, however, then we will reallocate to include all
1776 * the ever needed space. Also, if we need to reallocate it anyway,
1777 * make it big enough for everything we may ever need.
1780 if (head_need > 0 || skb_cloned(skb)) {
1781 head_need += IEEE80211_ENCRYPT_HEADROOM;
1782 head_need += local->tx_headroom;
1783 head_need = max_t(int, 0, head_need);
1784 if (ieee80211_skb_resize(local, skb, head_need, true))
1789 memcpy(skb_push(skb, encaps_len), encaps_data, encaps_len);
1790 nh_pos += encaps_len;
1791 h_pos += encaps_len;
1794 if (meshhdrlen > 0) {
1795 memcpy(skb_push(skb, meshhdrlen), &mesh_hdr, meshhdrlen);
1796 nh_pos += meshhdrlen;
1797 h_pos += meshhdrlen;
1800 if (ieee80211_is_data_qos(fc)) {
1801 __le16 *qos_control;
1803 qos_control = (__le16*) skb_push(skb, 2);
1804 memcpy(skb_push(skb, hdrlen - 2), &hdr, hdrlen - 2);
1806 * Maybe we could actually set some fields here, for now just
1807 * initialise to zero to indicate no special operation.
1811 memcpy(skb_push(skb, hdrlen), &hdr, hdrlen);
1816 dev->stats.tx_packets++;
1817 dev->stats.tx_bytes += skb->len;
1819 /* Update skb pointers to various headers since this modified frame
1820 * is going to go through Linux networking code that may potentially
1821 * need things like pointer to IP header. */
1822 skb_set_mac_header(skb, 0);
1823 skb_set_network_header(skb, nh_pos);
1824 skb_set_transport_header(skb, h_pos);
1826 memset(info, 0, sizeof(*info));
1828 dev->trans_start = jiffies;
1829 ieee80211_xmit(sdata, skb);
1831 return NETDEV_TX_OK;
1834 if (ret == NETDEV_TX_OK)
1842 * ieee80211_clear_tx_pending may not be called in a context where
1843 * it is possible that it packets could come in again.
1845 void ieee80211_clear_tx_pending(struct ieee80211_local *local)
1849 for (i = 0; i < local->hw.queues; i++)
1850 skb_queue_purge(&local->pending[i]);
1853 static bool ieee80211_tx_pending_skb(struct ieee80211_local *local,
1854 struct sk_buff *skb)
1856 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1857 struct ieee80211_sub_if_data *sdata;
1858 struct sta_info *sta;
1859 struct ieee80211_hdr *hdr;
1863 sdata = vif_to_sdata(info->control.vif);
1865 if (info->flags & IEEE80211_TX_INTFL_NEED_TXPROCESSING) {
1866 ieee80211_tx(sdata, skb, true);
1868 hdr = (struct ieee80211_hdr *)skb->data;
1869 sta = sta_info_get(local, hdr->addr1);
1871 ret = __ieee80211_tx(local, &skb, sta, true);
1872 if (ret != IEEE80211_TX_OK)
1880 * Transmit all pending packets. Called from tasklet.
1882 void ieee80211_tx_pending(unsigned long data)
1884 struct ieee80211_local *local = (struct ieee80211_local *)data;
1885 struct ieee80211_sub_if_data *sdata;
1886 unsigned long flags;
1892 spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
1893 for (i = 0; i < local->hw.queues; i++) {
1895 * If queue is stopped by something other than due to pending
1896 * frames, or we have no pending frames, proceed to next queue.
1898 if (local->queue_stop_reasons[i] ||
1899 skb_queue_empty(&local->pending[i]))
1902 while (!skb_queue_empty(&local->pending[i])) {
1903 struct sk_buff *skb = __skb_dequeue(&local->pending[i]);
1904 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1905 struct ieee80211_sub_if_data *sdata;
1907 if (WARN_ON(!info->control.vif)) {
1912 sdata = vif_to_sdata(info->control.vif);
1913 dev_hold(sdata->dev);
1914 spin_unlock_irqrestore(&local->queue_stop_reason_lock,
1917 txok = ieee80211_tx_pending_skb(local, skb);
1918 dev_put(sdata->dev);
1920 __skb_queue_head(&local->pending[i], skb);
1921 spin_lock_irqsave(&local->queue_stop_reason_lock,
1927 if (skb_queue_empty(&local->pending[i]))
1928 list_for_each_entry_rcu(sdata, &local->interfaces, list)
1929 netif_tx_wake_queue(
1930 netdev_get_tx_queue(sdata->dev, i));
1932 spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
1937 /* functions for drivers to get certain frames */
1939 static void ieee80211_beacon_add_tim(struct ieee80211_if_ap *bss,
1940 struct sk_buff *skb,
1941 struct beacon_data *beacon)
1945 int i, have_bits = 0, n1, n2;
1947 /* Generate bitmap for TIM only if there are any STAs in power save
1949 if (atomic_read(&bss->num_sta_ps) > 0)
1950 /* in the hope that this is faster than
1951 * checking byte-for-byte */
1952 have_bits = !bitmap_empty((unsigned long*)bss->tim,
1953 IEEE80211_MAX_AID+1);
1955 if (bss->dtim_count == 0)
1956 bss->dtim_count = beacon->dtim_period - 1;
1960 tim = pos = (u8 *) skb_put(skb, 6);
1961 *pos++ = WLAN_EID_TIM;
1963 *pos++ = bss->dtim_count;
1964 *pos++ = beacon->dtim_period;
1966 if (bss->dtim_count == 0 && !skb_queue_empty(&bss->ps_bc_buf))
1970 /* Find largest even number N1 so that bits numbered 1 through
1971 * (N1 x 8) - 1 in the bitmap are 0 and number N2 so that bits
1972 * (N2 + 1) x 8 through 2007 are 0. */
1974 for (i = 0; i < IEEE80211_MAX_TIM_LEN; i++) {
1981 for (i = IEEE80211_MAX_TIM_LEN - 1; i >= n1; i--) {
1988 /* Bitmap control */
1990 /* Part Virt Bitmap */
1991 memcpy(pos, bss->tim + n1, n2 - n1 + 1);
1993 tim[1] = n2 - n1 + 4;
1994 skb_put(skb, n2 - n1);
1996 *pos++ = aid0; /* Bitmap control */
1997 *pos++ = 0; /* Part Virt Bitmap */
2001 struct sk_buff *ieee80211_beacon_get(struct ieee80211_hw *hw,
2002 struct ieee80211_vif *vif)
2004 struct ieee80211_local *local = hw_to_local(hw);
2005 struct sk_buff *skb = NULL;
2006 struct ieee80211_tx_info *info;
2007 struct ieee80211_sub_if_data *sdata = NULL;
2008 struct ieee80211_if_ap *ap = NULL;
2009 struct beacon_data *beacon;
2010 struct ieee80211_supported_band *sband;
2011 enum ieee80211_band band = local->hw.conf.channel->band;
2013 sband = local->hw.wiphy->bands[band];
2017 sdata = vif_to_sdata(vif);
2019 if (sdata->vif.type == NL80211_IFTYPE_AP) {
2021 beacon = rcu_dereference(ap->beacon);
2024 * headroom, head length,
2025 * tail length and maximum TIM length
2027 skb = dev_alloc_skb(local->tx_headroom +
2029 beacon->tail_len + 256);
2033 skb_reserve(skb, local->tx_headroom);
2034 memcpy(skb_put(skb, beacon->head_len), beacon->head,
2038 * Not very nice, but we want to allow the driver to call
2039 * ieee80211_beacon_get() as a response to the set_tim()
2040 * callback. That, however, is already invoked under the
2041 * sta_lock to guarantee consistent and race-free update
2042 * of the tim bitmap in mac80211 and the driver.
2044 if (local->tim_in_locked_section) {
2045 ieee80211_beacon_add_tim(ap, skb, beacon);
2047 unsigned long flags;
2049 spin_lock_irqsave(&local->sta_lock, flags);
2050 ieee80211_beacon_add_tim(ap, skb, beacon);
2051 spin_unlock_irqrestore(&local->sta_lock, flags);
2055 memcpy(skb_put(skb, beacon->tail_len),
2056 beacon->tail, beacon->tail_len);
2059 } else if (sdata->vif.type == NL80211_IFTYPE_ADHOC) {
2060 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
2061 struct ieee80211_hdr *hdr;
2062 struct sk_buff *presp = rcu_dereference(ifibss->presp);
2067 skb = skb_copy(presp, GFP_ATOMIC);
2071 hdr = (struct ieee80211_hdr *) skb->data;
2072 hdr->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
2073 IEEE80211_STYPE_BEACON);
2074 } else if (ieee80211_vif_is_mesh(&sdata->vif)) {
2075 struct ieee80211_mgmt *mgmt;
2078 /* headroom, head length, tail length and maximum TIM length */
2079 skb = dev_alloc_skb(local->tx_headroom + 400);
2083 skb_reserve(skb, local->hw.extra_tx_headroom);
2084 mgmt = (struct ieee80211_mgmt *)
2085 skb_put(skb, 24 + sizeof(mgmt->u.beacon));
2086 memset(mgmt, 0, 24 + sizeof(mgmt->u.beacon));
2087 mgmt->frame_control =
2088 cpu_to_le16(IEEE80211_FTYPE_MGMT | IEEE80211_STYPE_BEACON);
2089 memset(mgmt->da, 0xff, ETH_ALEN);
2090 memcpy(mgmt->sa, sdata->dev->dev_addr, ETH_ALEN);
2091 /* BSSID is left zeroed, wildcard value */
2092 mgmt->u.beacon.beacon_int =
2093 cpu_to_le16(sdata->vif.bss_conf.beacon_int);
2094 mgmt->u.beacon.capab_info = 0x0; /* 0x0 for MPs */
2096 pos = skb_put(skb, 2);
2097 *pos++ = WLAN_EID_SSID;
2100 mesh_mgmt_ies_add(skb, sdata);
2106 info = IEEE80211_SKB_CB(skb);
2108 info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
2111 * XXX: For now, always use the lowest rate
2113 info->control.rates[0].idx = 0;
2114 info->control.rates[0].count = 1;
2115 info->control.rates[1].idx = -1;
2116 info->control.rates[2].idx = -1;
2117 info->control.rates[3].idx = -1;
2118 info->control.rates[4].idx = -1;
2119 BUILD_BUG_ON(IEEE80211_TX_MAX_RATES != 5);
2121 info->control.vif = vif;
2123 info->flags |= IEEE80211_TX_CTL_NO_ACK;
2124 info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT;
2125 info->flags |= IEEE80211_TX_CTL_ASSIGN_SEQ;
2130 EXPORT_SYMBOL(ieee80211_beacon_get);
2132 void ieee80211_rts_get(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
2133 const void *frame, size_t frame_len,
2134 const struct ieee80211_tx_info *frame_txctl,
2135 struct ieee80211_rts *rts)
2137 const struct ieee80211_hdr *hdr = frame;
2139 rts->frame_control =
2140 cpu_to_le16(IEEE80211_FTYPE_CTL | IEEE80211_STYPE_RTS);
2141 rts->duration = ieee80211_rts_duration(hw, vif, frame_len,
2143 memcpy(rts->ra, hdr->addr1, sizeof(rts->ra));
2144 memcpy(rts->ta, hdr->addr2, sizeof(rts->ta));
2146 EXPORT_SYMBOL(ieee80211_rts_get);
2148 void ieee80211_ctstoself_get(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
2149 const void *frame, size_t frame_len,
2150 const struct ieee80211_tx_info *frame_txctl,
2151 struct ieee80211_cts *cts)
2153 const struct ieee80211_hdr *hdr = frame;
2155 cts->frame_control =
2156 cpu_to_le16(IEEE80211_FTYPE_CTL | IEEE80211_STYPE_CTS);
2157 cts->duration = ieee80211_ctstoself_duration(hw, vif,
2158 frame_len, frame_txctl);
2159 memcpy(cts->ra, hdr->addr1, sizeof(cts->ra));
2161 EXPORT_SYMBOL(ieee80211_ctstoself_get);
2164 ieee80211_get_buffered_bc(struct ieee80211_hw *hw,
2165 struct ieee80211_vif *vif)
2167 struct ieee80211_local *local = hw_to_local(hw);
2168 struct sk_buff *skb = NULL;
2169 struct sta_info *sta;
2170 struct ieee80211_tx_data tx;
2171 struct ieee80211_sub_if_data *sdata;
2172 struct ieee80211_if_ap *bss = NULL;
2173 struct beacon_data *beacon;
2174 struct ieee80211_tx_info *info;
2176 sdata = vif_to_sdata(vif);
2180 beacon = rcu_dereference(bss->beacon);
2182 if (sdata->vif.type != NL80211_IFTYPE_AP || !beacon || !beacon->head)
2185 if (bss->dtim_count != 0)
2186 goto out; /* send buffered bc/mc only after DTIM beacon */
2189 skb = skb_dequeue(&bss->ps_bc_buf);
2192 local->total_ps_buffered--;
2194 if (!skb_queue_empty(&bss->ps_bc_buf) && skb->len >= 2) {
2195 struct ieee80211_hdr *hdr =
2196 (struct ieee80211_hdr *) skb->data;
2197 /* more buffered multicast/broadcast frames ==> set
2198 * MoreData flag in IEEE 802.11 header to inform PS
2200 hdr->frame_control |=
2201 cpu_to_le16(IEEE80211_FCTL_MOREDATA);
2204 if (!ieee80211_tx_prepare(sdata, &tx, skb))
2206 dev_kfree_skb_any(skb);
2209 info = IEEE80211_SKB_CB(skb);
2212 tx.flags |= IEEE80211_TX_PS_BUFFERED;
2213 tx.channel = local->hw.conf.channel;
2214 info->band = tx.channel->band;
2216 if (invoke_tx_handlers(&tx))
2223 EXPORT_SYMBOL(ieee80211_get_buffered_bc);
2225 void ieee80211_tx_skb(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb,
2228 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
2229 skb_set_mac_header(skb, 0);
2230 skb_set_network_header(skb, 0);
2231 skb_set_transport_header(skb, 0);
2234 info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
2236 /* send all internal mgmt frames on VO */
2237 skb_set_queue_mapping(skb, 0);
2240 * The other path calling ieee80211_xmit is from the tasklet,
2241 * and while we can handle concurrent transmissions locking
2242 * requirements are that we do not come into tx with bhs on.
2245 ieee80211_xmit(sdata, skb);