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 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 !(info->flags & IEEE80211_TX_CTL_PSPOLL_RESPONSE))) {
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->control.vif = &tx->sdata->vif;
404 info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
405 skb_queue_tail(&sta->ps_tx_buf, tx->skb);
408 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
409 else if (unlikely(test_sta_flags(sta, WLAN_STA_PS))) {
410 printk(KERN_DEBUG "%s: STA %pM in PS mode, but pspoll "
411 "set -> send frame\n", tx->dev->name,
414 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
419 static ieee80211_tx_result debug_noinline
420 ieee80211_tx_h_ps_buf(struct ieee80211_tx_data *tx)
422 if (unlikely(tx->flags & IEEE80211_TX_PS_BUFFERED))
425 if (tx->flags & IEEE80211_TX_UNICAST)
426 return ieee80211_tx_h_unicast_ps_buf(tx);
428 return ieee80211_tx_h_multicast_ps_buf(tx);
431 static ieee80211_tx_result debug_noinline
432 ieee80211_tx_h_select_key(struct ieee80211_tx_data *tx)
434 struct ieee80211_key *key = NULL;
435 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
436 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
438 if (unlikely(info->flags & IEEE80211_TX_INTFL_DONT_ENCRYPT))
440 else if (tx->sta && (key = rcu_dereference(tx->sta->key)))
442 else if (ieee80211_is_mgmt(hdr->frame_control) &&
443 (key = rcu_dereference(tx->sdata->default_mgmt_key)))
445 else if ((key = rcu_dereference(tx->sdata->default_key)))
447 else if (tx->sdata->drop_unencrypted &&
448 (tx->skb->protocol != cpu_to_be16(ETH_P_PAE)) &&
449 !(info->flags & IEEE80211_TX_CTL_INJECTED) &&
450 (!ieee80211_is_robust_mgmt_frame(hdr) ||
451 (ieee80211_is_action(hdr->frame_control) &&
452 tx->sta && test_sta_flags(tx->sta, WLAN_STA_MFP)))) {
453 I802_DEBUG_INC(tx->local->tx_handlers_drop_unencrypted);
459 tx->key->tx_rx_count++;
460 /* TODO: add threshold stuff again */
462 switch (tx->key->conf.alg) {
464 if (ieee80211_is_auth(hdr->frame_control))
467 if (!ieee80211_is_data_present(hdr->frame_control))
471 if (!ieee80211_is_data_present(hdr->frame_control) &&
472 !ieee80211_use_mfp(hdr->frame_control, tx->sta,
477 if (!ieee80211_is_mgmt(hdr->frame_control))
483 if (!tx->key || !(tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))
484 info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
489 static ieee80211_tx_result debug_noinline
490 ieee80211_tx_h_rate_ctrl(struct ieee80211_tx_data *tx)
492 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
493 struct ieee80211_hdr *hdr = (void *)tx->skb->data;
494 struct ieee80211_supported_band *sband;
495 struct ieee80211_rate *rate;
497 bool inval = false, rts = false, short_preamble = false;
498 struct ieee80211_tx_rate_control txrc;
501 memset(&txrc, 0, sizeof(txrc));
503 sband = tx->local->hw.wiphy->bands[tx->channel->band];
505 len = min_t(int, tx->skb->len + FCS_LEN,
506 tx->local->hw.wiphy->frag_threshold);
508 /* set up the tx rate control struct we give the RC algo */
509 txrc.hw = local_to_hw(tx->local);
511 txrc.bss_conf = &tx->sdata->vif.bss_conf;
513 txrc.reported_rate.idx = -1;
514 txrc.max_rate_idx = tx->sdata->max_ratectrl_rateidx;
516 /* set up RTS protection if desired */
517 if (len > tx->local->hw.wiphy->rts_threshold) {
518 txrc.rts = rts = true;
522 * Use short preamble if the BSS can handle it, but not for
523 * management frames unless we know the receiver can handle
524 * that -- the management frame might be to a station that
525 * just wants a probe response.
527 if (tx->sdata->vif.bss_conf.use_short_preamble &&
528 (ieee80211_is_data(hdr->frame_control) ||
529 (tx->sta && test_sta_flags(tx->sta, WLAN_STA_SHORT_PREAMBLE))))
530 txrc.short_preamble = short_preamble = true;
532 sta_flags = tx->sta ? get_sta_flags(tx->sta) : 0;
535 * Lets not bother rate control if we're associated and cannot
536 * talk to the sta. This should not happen.
538 if (WARN(test_bit(SCAN_SW_SCANNING, &tx->local->scanning) &&
539 (sta_flags & WLAN_STA_ASSOC) &&
540 !rate_usable_index_exists(sband, &tx->sta->sta),
541 "%s: Dropped data frame as no usable bitrate found while "
542 "scanning and associated. Target station: "
543 "%pM on %d GHz band\n",
544 tx->dev->name, hdr->addr1,
545 tx->channel->band ? 5 : 2))
549 * If we're associated with the sta at this point we know we can at
550 * least send the frame at the lowest bit rate.
552 rate_control_get_rate(tx->sdata, tx->sta, &txrc);
554 if (unlikely(info->control.rates[0].idx < 0))
557 if (txrc.reported_rate.idx < 0)
558 txrc.reported_rate = info->control.rates[0];
561 tx->sta->last_tx_rate = txrc.reported_rate;
563 if (unlikely(!info->control.rates[0].count))
564 info->control.rates[0].count = 1;
566 if (WARN_ON_ONCE((info->control.rates[0].count > 1) &&
567 (info->flags & IEEE80211_TX_CTL_NO_ACK)))
568 info->control.rates[0].count = 1;
570 if (is_multicast_ether_addr(hdr->addr1)) {
572 * XXX: verify the rate is in the basic rateset
578 * set up the RTS/CTS rate as the fastest basic rate
579 * that is not faster than the data rate
581 * XXX: Should this check all retry rates?
583 if (!(info->control.rates[0].flags & IEEE80211_TX_RC_MCS)) {
586 rate = &sband->bitrates[info->control.rates[0].idx];
588 for (i = 0; i < sband->n_bitrates; i++) {
589 /* must be a basic rate */
590 if (!(tx->sdata->vif.bss_conf.basic_rates & BIT(i)))
592 /* must not be faster than the data rate */
593 if (sband->bitrates[i].bitrate > rate->bitrate)
596 if (sband->bitrates[baserate].bitrate <
597 sband->bitrates[i].bitrate)
601 info->control.rts_cts_rate_idx = baserate;
604 for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) {
606 * make sure there's no valid rate following
607 * an invalid one, just in case drivers don't
608 * take the API seriously to stop at -1.
611 info->control.rates[i].idx = -1;
614 if (info->control.rates[i].idx < 0) {
620 * For now assume MCS is already set up correctly, this
623 if (info->control.rates[i].flags & IEEE80211_TX_RC_MCS) {
624 WARN_ON(info->control.rates[i].idx > 76);
628 /* set up RTS protection if desired */
630 info->control.rates[i].flags |=
631 IEEE80211_TX_RC_USE_RTS_CTS;
634 if (WARN_ON_ONCE(info->control.rates[i].idx >=
635 sband->n_bitrates)) {
636 info->control.rates[i].idx = -1;
640 rate = &sband->bitrates[info->control.rates[i].idx];
642 /* set up short preamble */
643 if (short_preamble &&
644 rate->flags & IEEE80211_RATE_SHORT_PREAMBLE)
645 info->control.rates[i].flags |=
646 IEEE80211_TX_RC_USE_SHORT_PREAMBLE;
648 /* set up G protection */
649 if (!rts && tx->sdata->vif.bss_conf.use_cts_prot &&
650 rate->flags & IEEE80211_RATE_ERP_G)
651 info->control.rates[i].flags |=
652 IEEE80211_TX_RC_USE_CTS_PROTECT;
658 static ieee80211_tx_result debug_noinline
659 ieee80211_tx_h_misc(struct ieee80211_tx_data *tx)
661 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
664 info->control.sta = &tx->sta->sta;
669 static ieee80211_tx_result debug_noinline
670 ieee80211_tx_h_sequence(struct ieee80211_tx_data *tx)
672 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
673 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
679 * Packet injection may want to control the sequence
680 * number, if we have no matching interface then we
681 * neither assign one ourselves nor ask the driver to.
683 if (unlikely(info->control.vif->type == NL80211_IFTYPE_MONITOR))
686 if (unlikely(ieee80211_is_ctl(hdr->frame_control)))
689 if (ieee80211_hdrlen(hdr->frame_control) < 24)
693 * Anything but QoS data that has a sequence number field
694 * (is long enough) gets a sequence number from the global
697 if (!ieee80211_is_data_qos(hdr->frame_control)) {
698 /* driver should assign sequence number */
699 info->flags |= IEEE80211_TX_CTL_ASSIGN_SEQ;
700 /* for pure STA mode without beacons, we can do it */
701 hdr->seq_ctrl = cpu_to_le16(tx->sdata->sequence_number);
702 tx->sdata->sequence_number += 0x10;
703 tx->sdata->sequence_number &= IEEE80211_SCTL_SEQ;
708 * This should be true for injected/management frames only, for
709 * management frames we have set the IEEE80211_TX_CTL_ASSIGN_SEQ
710 * above since they are not QoS-data frames.
715 /* include per-STA, per-TID sequence counter */
717 qc = ieee80211_get_qos_ctl(hdr);
718 tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
719 seq = &tx->sta->tid_seq[tid];
721 hdr->seq_ctrl = cpu_to_le16(*seq);
723 /* Increase the sequence number. */
724 *seq = (*seq + 0x10) & IEEE80211_SCTL_SEQ;
729 static int ieee80211_fragment(struct ieee80211_local *local,
730 struct sk_buff *skb, int hdrlen,
733 struct sk_buff *tail = skb, *tmp;
734 int per_fragm = frag_threshold - hdrlen - FCS_LEN;
735 int pos = hdrlen + per_fragm;
736 int rem = skb->len - hdrlen - per_fragm;
738 if (WARN_ON(rem < 0))
742 int fraglen = per_fragm;
747 tmp = dev_alloc_skb(local->tx_headroom +
749 IEEE80211_ENCRYPT_HEADROOM +
750 IEEE80211_ENCRYPT_TAILROOM);
755 skb_reserve(tmp, local->tx_headroom +
756 IEEE80211_ENCRYPT_HEADROOM);
757 /* copy control information */
758 memcpy(tmp->cb, skb->cb, sizeof(tmp->cb));
759 skb_copy_queue_mapping(tmp, skb);
760 tmp->priority = skb->priority;
763 /* copy header and data */
764 memcpy(skb_put(tmp, hdrlen), skb->data, hdrlen);
765 memcpy(skb_put(tmp, fraglen), skb->data + pos, fraglen);
770 skb->len = hdrlen + per_fragm;
774 static ieee80211_tx_result debug_noinline
775 ieee80211_tx_h_fragment(struct ieee80211_tx_data *tx)
777 struct sk_buff *skb = tx->skb;
778 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
779 struct ieee80211_hdr *hdr = (void *)skb->data;
780 int frag_threshold = tx->local->hw.wiphy->frag_threshold;
784 if (!(tx->flags & IEEE80211_TX_FRAGMENTED))
788 * Warn when submitting a fragmented A-MPDU frame and drop it.
789 * This scenario is handled in ieee80211_tx_prepare but extra
790 * caution taken here as fragmented ampdu may cause Tx stop.
792 if (WARN_ON(info->flags & IEEE80211_TX_CTL_AMPDU))
795 hdrlen = ieee80211_hdrlen(hdr->frame_control);
797 /* internal error, why is TX_FRAGMENTED set? */
798 if (WARN_ON(skb->len + FCS_LEN <= frag_threshold))
802 * Now fragment the frame. This will allocate all the fragments and
803 * chain them (using skb as the first fragment) to skb->next.
804 * During transmission, we will remove the successfully transmitted
805 * fragments from this list. When the low-level driver rejects one
806 * of the fragments then we will simply pretend to accept the skb
807 * but store it away as pending.
809 if (ieee80211_fragment(tx->local, skb, hdrlen, frag_threshold))
812 /* update duration/seq/flags of fragments */
816 const __le16 morefrags = cpu_to_le16(IEEE80211_FCTL_MOREFRAGS);
818 hdr = (void *)skb->data;
819 info = IEEE80211_SKB_CB(skb);
822 hdr->frame_control |= morefrags;
823 next_len = skb->next->len;
825 * No multi-rate retries for fragmented frames, that
826 * would completely throw off the NAV at other STAs.
828 info->control.rates[1].idx = -1;
829 info->control.rates[2].idx = -1;
830 info->control.rates[3].idx = -1;
831 info->control.rates[4].idx = -1;
832 BUILD_BUG_ON(IEEE80211_TX_MAX_RATES != 5);
833 info->flags &= ~IEEE80211_TX_CTL_RATE_CTRL_PROBE;
835 hdr->frame_control &= ~morefrags;
838 hdr->duration_id = ieee80211_duration(tx, 0, next_len);
839 hdr->seq_ctrl |= cpu_to_le16(fragnum & IEEE80211_SCTL_FRAG);
841 } while ((skb = skb->next));
846 static ieee80211_tx_result debug_noinline
847 ieee80211_tx_h_stats(struct ieee80211_tx_data *tx)
849 struct sk_buff *skb = tx->skb;
854 tx->sta->tx_packets++;
856 tx->sta->tx_fragments++;
857 tx->sta->tx_bytes += skb->len;
858 } while ((skb = skb->next));
863 static ieee80211_tx_result debug_noinline
864 ieee80211_tx_h_encrypt(struct ieee80211_tx_data *tx)
869 switch (tx->key->conf.alg) {
871 return ieee80211_crypto_wep_encrypt(tx);
873 return ieee80211_crypto_tkip_encrypt(tx);
875 return ieee80211_crypto_ccmp_encrypt(tx);
877 return ieee80211_crypto_aes_cmac_encrypt(tx);
885 static ieee80211_tx_result debug_noinline
886 ieee80211_tx_h_calculate_duration(struct ieee80211_tx_data *tx)
888 struct sk_buff *skb = tx->skb;
889 struct ieee80211_hdr *hdr;
894 hdr = (void *) skb->data;
895 if (unlikely(ieee80211_is_pspoll(hdr->frame_control)))
896 break; /* must not overwrite AID */
897 next_len = skb->next ? skb->next->len : 0;
898 group_addr = is_multicast_ether_addr(hdr->addr1);
901 ieee80211_duration(tx, group_addr, next_len);
902 } while ((skb = skb->next));
907 /* actual transmit path */
910 * deal with packet injection down monitor interface
911 * with Radiotap Header -- only called for monitor mode interface
913 static bool __ieee80211_parse_tx_radiotap(struct ieee80211_tx_data *tx,
917 * this is the moment to interpret and discard the radiotap header that
918 * must be at the start of the packet injected in Monitor mode
920 * Need to take some care with endian-ness since radiotap
921 * args are little-endian
924 struct ieee80211_radiotap_iterator iterator;
925 struct ieee80211_radiotap_header *rthdr =
926 (struct ieee80211_radiotap_header *) skb->data;
927 struct ieee80211_supported_band *sband;
928 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
929 int ret = ieee80211_radiotap_iterator_init(&iterator, rthdr, skb->len);
931 sband = tx->local->hw.wiphy->bands[tx->channel->band];
933 info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
934 tx->flags &= ~IEEE80211_TX_FRAGMENTED;
937 * for every radiotap entry that is present
938 * (ieee80211_radiotap_iterator_next returns -ENOENT when no more
939 * entries present, or -EINVAL on error)
943 ret = ieee80211_radiotap_iterator_next(&iterator);
948 /* see if this argument is something we can use */
949 switch (iterator.this_arg_index) {
951 * You must take care when dereferencing iterator.this_arg
952 * for multibyte types... the pointer is not aligned. Use
953 * get_unaligned((type *)iterator.this_arg) to dereference
954 * iterator.this_arg for type "type" safely on all arches.
956 case IEEE80211_RADIOTAP_FLAGS:
957 if (*iterator.this_arg & IEEE80211_RADIOTAP_F_FCS) {
959 * this indicates that the skb we have been
960 * handed has the 32-bit FCS CRC at the end...
961 * we should react to that by snipping it off
962 * because it will be recomputed and added
965 if (skb->len < (iterator.max_length + FCS_LEN))
968 skb_trim(skb, skb->len - FCS_LEN);
970 if (*iterator.this_arg & IEEE80211_RADIOTAP_F_WEP)
971 info->flags &= ~IEEE80211_TX_INTFL_DONT_ENCRYPT;
972 if (*iterator.this_arg & IEEE80211_RADIOTAP_F_FRAG)
973 tx->flags |= IEEE80211_TX_FRAGMENTED;
977 * Please update the file
978 * Documentation/networking/mac80211-injection.txt
979 * when parsing new fields here.
987 if (ret != -ENOENT) /* ie, if we didn't simply run out of fields */
991 * remove the radiotap header
992 * iterator->max_length was sanity-checked against
993 * skb->len by iterator init
995 skb_pull(skb, iterator.max_length);
1003 static ieee80211_tx_result
1004 ieee80211_tx_prepare(struct ieee80211_sub_if_data *sdata,
1005 struct ieee80211_tx_data *tx,
1006 struct sk_buff *skb)
1008 struct ieee80211_local *local = sdata->local;
1009 struct ieee80211_hdr *hdr;
1010 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1013 bool queued = false;
1015 memset(tx, 0, sizeof(*tx));
1017 tx->dev = sdata->dev; /* use original interface */
1020 tx->channel = local->hw.conf.channel;
1022 * Set this flag (used below to indicate "automatic fragmentation"),
1023 * it will be cleared/left by radiotap as desired.
1025 tx->flags |= IEEE80211_TX_FRAGMENTED;
1027 /* process and remove the injection radiotap header */
1028 if (unlikely(info->flags & IEEE80211_TX_CTL_INJECTED)) {
1029 if (!__ieee80211_parse_tx_radiotap(tx, skb))
1033 * __ieee80211_parse_tx_radiotap has now removed
1034 * the radiotap header that was present and pre-filled
1035 * 'tx' with tx control information.
1040 * If this flag is set to true anywhere, and we get here,
1041 * we are doing the needed processing, so remove the flag
1044 info->flags &= ~IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1046 hdr = (struct ieee80211_hdr *) skb->data;
1048 tx->sta = sta_info_get(local, hdr->addr1);
1050 if (tx->sta && ieee80211_is_data_qos(hdr->frame_control) &&
1051 (local->hw.flags & IEEE80211_HW_AMPDU_AGGREGATION)) {
1052 unsigned long flags;
1053 struct tid_ampdu_tx *tid_tx;
1055 qc = ieee80211_get_qos_ctl(hdr);
1056 tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
1058 spin_lock_irqsave(&tx->sta->lock, flags);
1060 * XXX: This spinlock could be fairly expensive, but see the
1061 * comment in agg-tx.c:ieee80211_agg_tx_operational().
1062 * One way to solve this would be to do something RCU-like
1063 * for managing the tid_tx struct and using atomic bitops
1064 * for the actual state -- by introducing an actual
1065 * 'operational' bit that would be possible. It would
1066 * require changing ieee80211_agg_tx_operational() to
1067 * set that bit, and changing the way tid_tx is managed
1068 * everywhere, including races between that bit and
1069 * tid_tx going away (tid_tx being added can be easily
1070 * committed to memory before the 'operational' bit).
1072 tid_tx = tx->sta->ampdu_mlme.tid_tx[tid];
1073 state = &tx->sta->ampdu_mlme.tid_state_tx[tid];
1074 if (*state == HT_AGG_STATE_OPERATIONAL) {
1075 info->flags |= IEEE80211_TX_CTL_AMPDU;
1076 } else if (*state != HT_AGG_STATE_IDLE) {
1079 info->control.vif = &sdata->vif;
1080 info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1081 __skb_queue_tail(&tid_tx->pending, skb);
1083 spin_unlock_irqrestore(&tx->sta->lock, flags);
1085 if (unlikely(queued))
1089 if (is_multicast_ether_addr(hdr->addr1)) {
1090 tx->flags &= ~IEEE80211_TX_UNICAST;
1091 info->flags |= IEEE80211_TX_CTL_NO_ACK;
1093 tx->flags |= IEEE80211_TX_UNICAST;
1094 if (unlikely(local->wifi_wme_noack_test))
1095 info->flags |= IEEE80211_TX_CTL_NO_ACK;
1097 info->flags &= ~IEEE80211_TX_CTL_NO_ACK;
1100 if (tx->flags & IEEE80211_TX_FRAGMENTED) {
1101 if ((tx->flags & IEEE80211_TX_UNICAST) &&
1102 skb->len + FCS_LEN > local->hw.wiphy->frag_threshold &&
1103 !(info->flags & IEEE80211_TX_CTL_AMPDU))
1104 tx->flags |= IEEE80211_TX_FRAGMENTED;
1106 tx->flags &= ~IEEE80211_TX_FRAGMENTED;
1110 info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT;
1111 else if (test_and_clear_sta_flags(tx->sta, WLAN_STA_CLEAR_PS_FILT))
1112 info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT;
1114 hdrlen = ieee80211_hdrlen(hdr->frame_control);
1115 if (skb->len > hdrlen + sizeof(rfc1042_header) + 2) {
1116 u8 *pos = &skb->data[hdrlen + sizeof(rfc1042_header)];
1117 tx->ethertype = (pos[0] << 8) | pos[1];
1119 info->flags |= IEEE80211_TX_CTL_FIRST_FRAGMENT;
1124 static int __ieee80211_tx(struct ieee80211_local *local,
1125 struct sk_buff **skbp,
1126 struct sta_info *sta,
1129 struct sk_buff *skb = *skbp, *next;
1130 struct ieee80211_tx_info *info;
1131 struct ieee80211_sub_if_data *sdata;
1132 unsigned long flags;
1137 int q = skb_get_queue_mapping(skb);
1139 spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
1140 ret = IEEE80211_TX_OK;
1141 if (local->queue_stop_reasons[q] ||
1142 (!txpending && !skb_queue_empty(&local->pending[q])))
1143 ret = IEEE80211_TX_PENDING;
1144 spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
1145 if (ret != IEEE80211_TX_OK)
1148 info = IEEE80211_SKB_CB(skb);
1151 info->flags &= ~(IEEE80211_TX_CTL_CLEAR_PS_FILT |
1152 IEEE80211_TX_CTL_FIRST_FRAGMENT);
1158 info->flags |= IEEE80211_TX_CTL_MORE_FRAMES;
1160 sdata = vif_to_sdata(info->control.vif);
1162 switch (sdata->vif.type) {
1163 case NL80211_IFTYPE_MONITOR:
1164 info->control.vif = NULL;
1166 case NL80211_IFTYPE_AP_VLAN:
1167 info->control.vif = &container_of(sdata->bss,
1168 struct ieee80211_sub_if_data, u.ap)->vif;
1175 ret = drv_tx(local, skb);
1176 if (WARN_ON(ret != NETDEV_TX_OK && skb->len != len)) {
1180 if (ret != NETDEV_TX_OK) {
1181 info->control.vif = &sdata->vif;
1182 return IEEE80211_TX_AGAIN;
1186 ieee80211_led_tx(local, 1);
1190 return IEEE80211_TX_OK;
1194 * Invoke TX handlers, return 0 on success and non-zero if the
1195 * frame was dropped or queued.
1197 static int invoke_tx_handlers(struct ieee80211_tx_data *tx)
1199 struct sk_buff *skb = tx->skb;
1200 ieee80211_tx_result res = TX_DROP;
1202 #define CALL_TXH(txh) \
1204 if (res != TX_CONTINUE) \
1207 CALL_TXH(ieee80211_tx_h_check_assoc)
1208 CALL_TXH(ieee80211_tx_h_ps_buf)
1209 CALL_TXH(ieee80211_tx_h_select_key)
1210 CALL_TXH(ieee80211_tx_h_michael_mic_add)
1211 CALL_TXH(ieee80211_tx_h_rate_ctrl)
1212 CALL_TXH(ieee80211_tx_h_misc)
1213 CALL_TXH(ieee80211_tx_h_sequence)
1214 CALL_TXH(ieee80211_tx_h_fragment)
1215 /* handlers after fragment must be aware of tx info fragmentation! */
1216 CALL_TXH(ieee80211_tx_h_stats)
1217 CALL_TXH(ieee80211_tx_h_encrypt)
1218 CALL_TXH(ieee80211_tx_h_calculate_duration)
1222 if (unlikely(res == TX_DROP)) {
1223 I802_DEBUG_INC(tx->local->tx_handlers_drop);
1225 struct sk_buff *next;
1232 } else if (unlikely(res == TX_QUEUED)) {
1233 I802_DEBUG_INC(tx->local->tx_handlers_queued);
1240 static void ieee80211_tx(struct ieee80211_sub_if_data *sdata,
1241 struct sk_buff *skb, bool txpending)
1243 struct ieee80211_local *local = sdata->local;
1244 struct ieee80211_tx_data tx;
1245 ieee80211_tx_result res_prepare;
1246 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1247 struct sk_buff *next;
1248 unsigned long flags;
1252 queue = skb_get_queue_mapping(skb);
1254 if (unlikely(skb->len < 10)) {
1261 /* initialises tx */
1262 res_prepare = ieee80211_tx_prepare(sdata, &tx, skb);
1264 if (unlikely(res_prepare == TX_DROP)) {
1268 } else if (unlikely(res_prepare == TX_QUEUED)) {
1273 tx.channel = local->hw.conf.channel;
1274 info->band = tx.channel->band;
1276 if (invoke_tx_handlers(&tx))
1281 ret = __ieee80211_tx(local, &tx.skb, tx.sta, txpending);
1283 case IEEE80211_TX_OK:
1285 case IEEE80211_TX_AGAIN:
1287 * Since there are no fragmented frames on A-MPDU
1288 * queues, there's no reason for a driver to reject
1289 * a frame there, warn and drop it.
1291 if (WARN_ON(info->flags & IEEE80211_TX_CTL_AMPDU))
1294 case IEEE80211_TX_PENDING:
1297 spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
1299 if (local->queue_stop_reasons[queue] ||
1300 !skb_queue_empty(&local->pending[queue])) {
1302 * if queue is stopped, queue up frames for later
1303 * transmission from the tasklet
1308 if (unlikely(txpending))
1309 __skb_queue_head(&local->pending[queue],
1312 __skb_queue_tail(&local->pending[queue],
1314 } while ((skb = next));
1316 spin_unlock_irqrestore(&local->queue_stop_reason_lock,
1320 * otherwise retry, but this is a race condition or
1321 * a driver bug (which we warn about if it persists)
1323 spin_unlock_irqrestore(&local->queue_stop_reason_lock,
1327 if (WARN(retries > 10, "tx refused but queue active\n"))
1347 /* device xmit handlers */
1349 static int ieee80211_skb_resize(struct ieee80211_local *local,
1350 struct sk_buff *skb,
1351 int head_need, bool may_encrypt)
1356 * This could be optimised, devices that do full hardware
1357 * crypto (including TKIP MMIC) need no tailroom... But we
1358 * have no drivers for such devices currently.
1361 tail_need = IEEE80211_ENCRYPT_TAILROOM;
1362 tail_need -= skb_tailroom(skb);
1363 tail_need = max_t(int, tail_need, 0);
1366 if (head_need || tail_need) {
1367 /* Sorry. Can't account for this any more */
1371 if (skb_header_cloned(skb))
1372 I802_DEBUG_INC(local->tx_expand_skb_head_cloned);
1374 I802_DEBUG_INC(local->tx_expand_skb_head);
1376 if (pskb_expand_head(skb, head_need, tail_need, GFP_ATOMIC)) {
1377 printk(KERN_DEBUG "%s: failed to reallocate TX buffer\n",
1378 wiphy_name(local->hw.wiphy));
1382 /* update truesize too */
1383 skb->truesize += head_need + tail_need;
1388 static void ieee80211_xmit(struct ieee80211_sub_if_data *sdata,
1389 struct sk_buff *skb)
1391 struct ieee80211_local *local = sdata->local;
1392 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1393 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1394 struct ieee80211_sub_if_data *tmp_sdata;
1398 dev_hold(sdata->dev);
1400 if ((local->hw.flags & IEEE80211_HW_PS_NULLFUNC_STACK) &&
1401 local->hw.conf.dynamic_ps_timeout > 0 &&
1402 !(local->scanning) && local->ps_sdata) {
1403 if (local->hw.conf.flags & IEEE80211_CONF_PS) {
1404 ieee80211_stop_queues_by_reason(&local->hw,
1405 IEEE80211_QUEUE_STOP_REASON_PS);
1406 ieee80211_queue_work(&local->hw,
1407 &local->dynamic_ps_disable_work);
1410 mod_timer(&local->dynamic_ps_timer, jiffies +
1411 msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout));
1414 info->flags |= IEEE80211_TX_CTL_REQ_TX_STATUS;
1416 if (ieee80211_vif_is_mesh(&sdata->vif) &&
1417 ieee80211_is_data(hdr->frame_control)) {
1418 if (is_multicast_ether_addr(hdr->addr3))
1419 memcpy(hdr->addr1, hdr->addr3, ETH_ALEN);
1421 if (mesh_nexthop_lookup(skb, sdata)) {
1422 dev_put(sdata->dev);
1425 } else if (unlikely(sdata->vif.type == NL80211_IFTYPE_MONITOR)) {
1429 info->flags |= IEEE80211_TX_CTL_INJECTED;
1431 len_rthdr = ieee80211_get_radiotap_len(skb->data);
1432 hdr = (struct ieee80211_hdr *)(skb->data + len_rthdr);
1433 hdrlen = ieee80211_hdrlen(hdr->frame_control);
1435 /* check the header is complete in the frame */
1436 if (likely(skb->len >= len_rthdr + hdrlen)) {
1438 * We process outgoing injected frames that have a
1439 * local address we handle as though they are our
1441 * This code here isn't entirely correct, the local
1442 * MAC address is not necessarily enough to find
1443 * the interface to use; for that proper VLAN/WDS
1444 * support we will need a different mechanism.
1448 list_for_each_entry_rcu(tmp_sdata, &local->interfaces,
1450 if (!netif_running(tmp_sdata->dev))
1452 if (tmp_sdata->vif.type != NL80211_IFTYPE_AP)
1454 if (compare_ether_addr(tmp_sdata->dev->dev_addr,
1456 dev_hold(tmp_sdata->dev);
1457 dev_put(sdata->dev);
1466 may_encrypt = !(info->flags & IEEE80211_TX_INTFL_DONT_ENCRYPT);
1468 headroom = local->tx_headroom;
1470 headroom += IEEE80211_ENCRYPT_HEADROOM;
1471 headroom -= skb_headroom(skb);
1472 headroom = max_t(int, 0, headroom);
1474 if (ieee80211_skb_resize(local, skb, headroom, may_encrypt)) {
1476 dev_put(sdata->dev);
1480 info->control.vif = &sdata->vif;
1482 ieee80211_select_queue(local, skb);
1483 ieee80211_tx(sdata, skb, false);
1484 dev_put(sdata->dev);
1487 int ieee80211_monitor_start_xmit(struct sk_buff *skb,
1488 struct net_device *dev)
1490 struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
1491 struct ieee80211_channel *chan = local->hw.conf.channel;
1492 struct ieee80211_radiotap_header *prthdr =
1493 (struct ieee80211_radiotap_header *)skb->data;
1494 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1498 * Frame injection is not allowed if beaconing is not allowed
1499 * or if we need radar detection. Beaconing is usually not allowed when
1500 * the mode or operation (Adhoc, AP, Mesh) does not support DFS.
1501 * Passive scan is also used in world regulatory domains where
1502 * your country is not known and as such it should be treated as
1503 * NO TX unless the channel is explicitly allowed in which case
1504 * your current regulatory domain would not have the passive scan
1507 * Since AP mode uses monitor interfaces to inject/TX management
1508 * frames we can make AP mode the exception to this rule once it
1509 * supports radar detection as its implementation can deal with
1510 * radar detection by itself. We can do that later by adding a
1511 * monitor flag interfaces used for AP support.
1513 if ((chan->flags & (IEEE80211_CHAN_NO_IBSS | IEEE80211_CHAN_RADAR |
1514 IEEE80211_CHAN_PASSIVE_SCAN)))
1517 /* check for not even having the fixed radiotap header part */
1518 if (unlikely(skb->len < sizeof(struct ieee80211_radiotap_header)))
1519 goto fail; /* too short to be possibly valid */
1521 /* is it a header version we can trust to find length from? */
1522 if (unlikely(prthdr->it_version))
1523 goto fail; /* only version 0 is supported */
1525 /* then there must be a radiotap header with a length we can use */
1526 len_rthdr = ieee80211_get_radiotap_len(skb->data);
1528 /* does the skb contain enough to deliver on the alleged length? */
1529 if (unlikely(skb->len < len_rthdr))
1530 goto fail; /* skb too short for claimed rt header extent */
1533 * fix up the pointers accounting for the radiotap
1534 * header still being in there. We are being given
1535 * a precooked IEEE80211 header so no need for
1538 skb_set_mac_header(skb, len_rthdr);
1540 * these are just fixed to the end of the rt area since we
1541 * don't have any better information and at this point, nobody cares
1543 skb_set_network_header(skb, len_rthdr);
1544 skb_set_transport_header(skb, len_rthdr);
1546 memset(info, 0, sizeof(*info));
1548 /* pass the radiotap header up to xmit */
1549 ieee80211_xmit(IEEE80211_DEV_TO_SUB_IF(dev), skb);
1550 return NETDEV_TX_OK;
1554 return NETDEV_TX_OK; /* meaning, we dealt with the skb */
1558 * ieee80211_subif_start_xmit - netif start_xmit function for Ethernet-type
1559 * subinterfaces (wlan#, WDS, and VLAN interfaces)
1560 * @skb: packet to be sent
1561 * @dev: incoming interface
1563 * Returns: 0 on success (and frees skb in this case) or 1 on failure (skb will
1564 * not be freed, and caller is responsible for either retrying later or freeing
1567 * This function takes in an Ethernet header and encapsulates it with suitable
1568 * IEEE 802.11 header based on which interface the packet is coming in. The
1569 * encapsulated packet will then be passed to master interface, wlan#.11, for
1570 * transmission (through low-level driver).
1572 int ieee80211_subif_start_xmit(struct sk_buff *skb,
1573 struct net_device *dev)
1575 struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1576 struct ieee80211_local *local = sdata->local;
1577 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1578 int ret = NETDEV_TX_BUSY, head_need;
1579 u16 ethertype, hdrlen, meshhdrlen = 0;
1581 struct ieee80211_hdr hdr;
1582 struct ieee80211s_hdr mesh_hdr;
1583 const u8 *encaps_data;
1584 int encaps_len, skip_header_bytes;
1586 struct sta_info *sta;
1589 if (unlikely(skb->len < ETH_HLEN)) {
1594 nh_pos = skb_network_header(skb) - skb->data;
1595 h_pos = skb_transport_header(skb) - skb->data;
1597 /* convert Ethernet header to proper 802.11 header (based on
1598 * operation mode) */
1599 ethertype = (skb->data[12] << 8) | skb->data[13];
1600 fc = cpu_to_le16(IEEE80211_FTYPE_DATA | IEEE80211_STYPE_DATA);
1602 switch (sdata->vif.type) {
1603 case NL80211_IFTYPE_AP:
1604 case NL80211_IFTYPE_AP_VLAN:
1605 fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS);
1607 memcpy(hdr.addr1, skb->data, ETH_ALEN);
1608 memcpy(hdr.addr2, dev->dev_addr, ETH_ALEN);
1609 memcpy(hdr.addr3, skb->data + ETH_ALEN, ETH_ALEN);
1612 case NL80211_IFTYPE_WDS:
1613 fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS);
1615 memcpy(hdr.addr1, sdata->u.wds.remote_addr, ETH_ALEN);
1616 memcpy(hdr.addr2, dev->dev_addr, ETH_ALEN);
1617 memcpy(hdr.addr3, skb->data, ETH_ALEN);
1618 memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN);
1621 #ifdef CONFIG_MAC80211_MESH
1622 case NL80211_IFTYPE_MESH_POINT:
1623 fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS);
1624 if (!sdata->u.mesh.mshcfg.dot11MeshTTL) {
1625 /* Do not send frames with mesh_ttl == 0 */
1626 sdata->u.mesh.mshstats.dropped_frames_ttl++;
1630 memset(&mesh_hdr, 0, sizeof(mesh_hdr));
1632 if (compare_ether_addr(dev->dev_addr,
1633 skb->data + ETH_ALEN) == 0) {
1635 memset(hdr.addr1, 0, ETH_ALEN);
1636 memcpy(hdr.addr2, dev->dev_addr, ETH_ALEN);
1637 memcpy(hdr.addr3, skb->data, ETH_ALEN);
1638 memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN);
1639 meshhdrlen = ieee80211_new_mesh_header(&mesh_hdr, sdata);
1641 /* packet from other interface */
1642 struct mesh_path *mppath;
1644 memset(hdr.addr1, 0, ETH_ALEN);
1645 memcpy(hdr.addr2, dev->dev_addr, ETH_ALEN);
1646 memcpy(hdr.addr4, dev->dev_addr, ETH_ALEN);
1648 if (is_multicast_ether_addr(skb->data))
1649 memcpy(hdr.addr3, skb->data, ETH_ALEN);
1652 mppath = mpp_path_lookup(skb->data, sdata);
1654 memcpy(hdr.addr3, mppath->mpp, ETH_ALEN);
1656 memset(hdr.addr3, 0xff, ETH_ALEN);
1660 mesh_hdr.flags |= MESH_FLAGS_AE_A5_A6;
1661 mesh_hdr.ttl = sdata->u.mesh.mshcfg.dot11MeshTTL;
1662 put_unaligned(cpu_to_le32(sdata->u.mesh.mesh_seqnum), &mesh_hdr.seqnum);
1663 memcpy(mesh_hdr.eaddr1, skb->data, ETH_ALEN);
1664 memcpy(mesh_hdr.eaddr2, skb->data + ETH_ALEN, ETH_ALEN);
1665 sdata->u.mesh.mesh_seqnum++;
1671 case NL80211_IFTYPE_STATION:
1672 fc |= cpu_to_le16(IEEE80211_FCTL_TODS);
1674 memcpy(hdr.addr1, sdata->u.mgd.bssid, ETH_ALEN);
1675 memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
1676 memcpy(hdr.addr3, skb->data, ETH_ALEN);
1679 case NL80211_IFTYPE_ADHOC:
1681 memcpy(hdr.addr1, skb->data, ETH_ALEN);
1682 memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
1683 memcpy(hdr.addr3, sdata->u.ibss.bssid, ETH_ALEN);
1692 * There's no need to try to look up the destination
1693 * if it is a multicast address (which can only happen
1696 if (!is_multicast_ether_addr(hdr.addr1)) {
1698 sta = sta_info_get(local, hdr.addr1);
1700 sta_flags = get_sta_flags(sta);
1704 /* receiver and we are QoS enabled, use a QoS type frame */
1705 if ((sta_flags & WLAN_STA_WME) && local->hw.queues >= 4) {
1706 fc |= cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
1711 * Drop unicast frames to unauthorised stations unless they are
1712 * EAPOL frames from the local station.
1714 if (!ieee80211_vif_is_mesh(&sdata->vif) &&
1715 unlikely(!is_multicast_ether_addr(hdr.addr1) &&
1716 !(sta_flags & WLAN_STA_AUTHORIZED) &&
1717 !(ethertype == ETH_P_PAE &&
1718 compare_ether_addr(dev->dev_addr,
1719 skb->data + ETH_ALEN) == 0))) {
1720 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
1721 if (net_ratelimit())
1722 printk(KERN_DEBUG "%s: dropped frame to %pM"
1723 " (unauthorized port)\n", dev->name,
1727 I802_DEBUG_INC(local->tx_handlers_drop_unauth_port);
1733 hdr.frame_control = fc;
1734 hdr.duration_id = 0;
1737 skip_header_bytes = ETH_HLEN;
1738 if (ethertype == ETH_P_AARP || ethertype == ETH_P_IPX) {
1739 encaps_data = bridge_tunnel_header;
1740 encaps_len = sizeof(bridge_tunnel_header);
1741 skip_header_bytes -= 2;
1742 } else if (ethertype >= 0x600) {
1743 encaps_data = rfc1042_header;
1744 encaps_len = sizeof(rfc1042_header);
1745 skip_header_bytes -= 2;
1751 skb_pull(skb, skip_header_bytes);
1752 nh_pos -= skip_header_bytes;
1753 h_pos -= skip_header_bytes;
1755 head_need = hdrlen + encaps_len + meshhdrlen - skb_headroom(skb);
1758 * So we need to modify the skb header and hence need a copy of
1759 * that. The head_need variable above doesn't, so far, include
1760 * the needed header space that we don't need right away. If we
1761 * can, then we don't reallocate right now but only after the
1762 * frame arrives at the master device (if it does...)
1764 * If we cannot, however, then we will reallocate to include all
1765 * the ever needed space. Also, if we need to reallocate it anyway,
1766 * make it big enough for everything we may ever need.
1769 if (head_need > 0 || skb_cloned(skb)) {
1770 head_need += IEEE80211_ENCRYPT_HEADROOM;
1771 head_need += local->tx_headroom;
1772 head_need = max_t(int, 0, head_need);
1773 if (ieee80211_skb_resize(local, skb, head_need, true))
1778 memcpy(skb_push(skb, encaps_len), encaps_data, encaps_len);
1779 nh_pos += encaps_len;
1780 h_pos += encaps_len;
1783 if (meshhdrlen > 0) {
1784 memcpy(skb_push(skb, meshhdrlen), &mesh_hdr, meshhdrlen);
1785 nh_pos += meshhdrlen;
1786 h_pos += meshhdrlen;
1789 if (ieee80211_is_data_qos(fc)) {
1790 __le16 *qos_control;
1792 qos_control = (__le16*) skb_push(skb, 2);
1793 memcpy(skb_push(skb, hdrlen - 2), &hdr, hdrlen - 2);
1795 * Maybe we could actually set some fields here, for now just
1796 * initialise to zero to indicate no special operation.
1800 memcpy(skb_push(skb, hdrlen), &hdr, hdrlen);
1805 dev->stats.tx_packets++;
1806 dev->stats.tx_bytes += skb->len;
1808 /* Update skb pointers to various headers since this modified frame
1809 * is going to go through Linux networking code that may potentially
1810 * need things like pointer to IP header. */
1811 skb_set_mac_header(skb, 0);
1812 skb_set_network_header(skb, nh_pos);
1813 skb_set_transport_header(skb, h_pos);
1815 memset(info, 0, sizeof(*info));
1817 dev->trans_start = jiffies;
1818 ieee80211_xmit(sdata, skb);
1820 return NETDEV_TX_OK;
1823 if (ret == NETDEV_TX_OK)
1831 * ieee80211_clear_tx_pending may not be called in a context where
1832 * it is possible that it packets could come in again.
1834 void ieee80211_clear_tx_pending(struct ieee80211_local *local)
1838 for (i = 0; i < local->hw.queues; i++)
1839 skb_queue_purge(&local->pending[i]);
1842 static bool ieee80211_tx_pending_skb(struct ieee80211_local *local,
1843 struct sk_buff *skb)
1845 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1846 struct ieee80211_sub_if_data *sdata;
1847 struct sta_info *sta;
1848 struct ieee80211_hdr *hdr;
1852 sdata = vif_to_sdata(info->control.vif);
1854 if (info->flags & IEEE80211_TX_INTFL_NEED_TXPROCESSING) {
1855 ieee80211_tx(sdata, skb, true);
1857 hdr = (struct ieee80211_hdr *)skb->data;
1858 sta = sta_info_get(local, hdr->addr1);
1860 ret = __ieee80211_tx(local, &skb, sta, true);
1861 if (ret != IEEE80211_TX_OK)
1869 * Transmit all pending packets. Called from tasklet.
1871 void ieee80211_tx_pending(unsigned long data)
1873 struct ieee80211_local *local = (struct ieee80211_local *)data;
1874 unsigned long flags;
1880 spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
1881 for (i = 0; i < local->hw.queues; i++) {
1883 * If queue is stopped by something other than due to pending
1884 * frames, or we have no pending frames, proceed to next queue.
1886 if (local->queue_stop_reasons[i] ||
1887 skb_queue_empty(&local->pending[i]))
1890 while (!skb_queue_empty(&local->pending[i])) {
1891 struct sk_buff *skb = __skb_dequeue(&local->pending[i]);
1892 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1893 struct ieee80211_sub_if_data *sdata;
1895 if (WARN_ON(!info->control.vif)) {
1900 sdata = vif_to_sdata(info->control.vif);
1901 dev_hold(sdata->dev);
1902 spin_unlock_irqrestore(&local->queue_stop_reason_lock,
1905 txok = ieee80211_tx_pending_skb(local, skb);
1906 dev_put(sdata->dev);
1908 __skb_queue_head(&local->pending[i], skb);
1909 spin_lock_irqsave(&local->queue_stop_reason_lock,
1915 spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
1920 /* functions for drivers to get certain frames */
1922 static void ieee80211_beacon_add_tim(struct ieee80211_if_ap *bss,
1923 struct sk_buff *skb,
1924 struct beacon_data *beacon)
1928 int i, have_bits = 0, n1, n2;
1930 /* Generate bitmap for TIM only if there are any STAs in power save
1932 if (atomic_read(&bss->num_sta_ps) > 0)
1933 /* in the hope that this is faster than
1934 * checking byte-for-byte */
1935 have_bits = !bitmap_empty((unsigned long*)bss->tim,
1936 IEEE80211_MAX_AID+1);
1938 if (bss->dtim_count == 0)
1939 bss->dtim_count = beacon->dtim_period - 1;
1943 tim = pos = (u8 *) skb_put(skb, 6);
1944 *pos++ = WLAN_EID_TIM;
1946 *pos++ = bss->dtim_count;
1947 *pos++ = beacon->dtim_period;
1949 if (bss->dtim_count == 0 && !skb_queue_empty(&bss->ps_bc_buf))
1953 /* Find largest even number N1 so that bits numbered 1 through
1954 * (N1 x 8) - 1 in the bitmap are 0 and number N2 so that bits
1955 * (N2 + 1) x 8 through 2007 are 0. */
1957 for (i = 0; i < IEEE80211_MAX_TIM_LEN; i++) {
1964 for (i = IEEE80211_MAX_TIM_LEN - 1; i >= n1; i--) {
1971 /* Bitmap control */
1973 /* Part Virt Bitmap */
1974 memcpy(pos, bss->tim + n1, n2 - n1 + 1);
1976 tim[1] = n2 - n1 + 4;
1977 skb_put(skb, n2 - n1);
1979 *pos++ = aid0; /* Bitmap control */
1980 *pos++ = 0; /* Part Virt Bitmap */
1984 struct sk_buff *ieee80211_beacon_get(struct ieee80211_hw *hw,
1985 struct ieee80211_vif *vif)
1987 struct ieee80211_local *local = hw_to_local(hw);
1988 struct sk_buff *skb = NULL;
1989 struct ieee80211_tx_info *info;
1990 struct ieee80211_sub_if_data *sdata = NULL;
1991 struct ieee80211_if_ap *ap = NULL;
1992 struct beacon_data *beacon;
1993 struct ieee80211_supported_band *sband;
1994 enum ieee80211_band band = local->hw.conf.channel->band;
1996 sband = local->hw.wiphy->bands[band];
2000 sdata = vif_to_sdata(vif);
2002 if (sdata->vif.type == NL80211_IFTYPE_AP) {
2004 beacon = rcu_dereference(ap->beacon);
2007 * headroom, head length,
2008 * tail length and maximum TIM length
2010 skb = dev_alloc_skb(local->tx_headroom +
2012 beacon->tail_len + 256);
2016 skb_reserve(skb, local->tx_headroom);
2017 memcpy(skb_put(skb, beacon->head_len), beacon->head,
2021 * Not very nice, but we want to allow the driver to call
2022 * ieee80211_beacon_get() as a response to the set_tim()
2023 * callback. That, however, is already invoked under the
2024 * sta_lock to guarantee consistent and race-free update
2025 * of the tim bitmap in mac80211 and the driver.
2027 if (local->tim_in_locked_section) {
2028 ieee80211_beacon_add_tim(ap, skb, beacon);
2030 unsigned long flags;
2032 spin_lock_irqsave(&local->sta_lock, flags);
2033 ieee80211_beacon_add_tim(ap, skb, beacon);
2034 spin_unlock_irqrestore(&local->sta_lock, flags);
2038 memcpy(skb_put(skb, beacon->tail_len),
2039 beacon->tail, beacon->tail_len);
2042 } else if (sdata->vif.type == NL80211_IFTYPE_ADHOC) {
2043 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
2044 struct ieee80211_hdr *hdr;
2045 struct sk_buff *presp = rcu_dereference(ifibss->presp);
2050 skb = skb_copy(presp, GFP_ATOMIC);
2054 hdr = (struct ieee80211_hdr *) skb->data;
2055 hdr->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
2056 IEEE80211_STYPE_BEACON);
2057 } else if (ieee80211_vif_is_mesh(&sdata->vif)) {
2058 struct ieee80211_mgmt *mgmt;
2061 /* headroom, head length, tail length and maximum TIM length */
2062 skb = dev_alloc_skb(local->tx_headroom + 400);
2066 skb_reserve(skb, local->hw.extra_tx_headroom);
2067 mgmt = (struct ieee80211_mgmt *)
2068 skb_put(skb, 24 + sizeof(mgmt->u.beacon));
2069 memset(mgmt, 0, 24 + sizeof(mgmt->u.beacon));
2070 mgmt->frame_control =
2071 cpu_to_le16(IEEE80211_FTYPE_MGMT | IEEE80211_STYPE_BEACON);
2072 memset(mgmt->da, 0xff, ETH_ALEN);
2073 memcpy(mgmt->sa, sdata->dev->dev_addr, ETH_ALEN);
2074 /* BSSID is left zeroed, wildcard value */
2075 mgmt->u.beacon.beacon_int =
2076 cpu_to_le16(sdata->vif.bss_conf.beacon_int);
2077 mgmt->u.beacon.capab_info = 0x0; /* 0x0 for MPs */
2079 pos = skb_put(skb, 2);
2080 *pos++ = WLAN_EID_SSID;
2083 mesh_mgmt_ies_add(skb, sdata);
2089 info = IEEE80211_SKB_CB(skb);
2091 info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
2094 * XXX: For now, always use the lowest rate
2096 info->control.rates[0].idx = 0;
2097 info->control.rates[0].count = 1;
2098 info->control.rates[1].idx = -1;
2099 info->control.rates[2].idx = -1;
2100 info->control.rates[3].idx = -1;
2101 info->control.rates[4].idx = -1;
2102 BUILD_BUG_ON(IEEE80211_TX_MAX_RATES != 5);
2104 info->control.vif = vif;
2106 info->flags |= IEEE80211_TX_CTL_NO_ACK;
2107 info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT;
2108 info->flags |= IEEE80211_TX_CTL_ASSIGN_SEQ;
2113 EXPORT_SYMBOL(ieee80211_beacon_get);
2115 void ieee80211_rts_get(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
2116 const void *frame, size_t frame_len,
2117 const struct ieee80211_tx_info *frame_txctl,
2118 struct ieee80211_rts *rts)
2120 const struct ieee80211_hdr *hdr = frame;
2122 rts->frame_control =
2123 cpu_to_le16(IEEE80211_FTYPE_CTL | IEEE80211_STYPE_RTS);
2124 rts->duration = ieee80211_rts_duration(hw, vif, frame_len,
2126 memcpy(rts->ra, hdr->addr1, sizeof(rts->ra));
2127 memcpy(rts->ta, hdr->addr2, sizeof(rts->ta));
2129 EXPORT_SYMBOL(ieee80211_rts_get);
2131 void ieee80211_ctstoself_get(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
2132 const void *frame, size_t frame_len,
2133 const struct ieee80211_tx_info *frame_txctl,
2134 struct ieee80211_cts *cts)
2136 const struct ieee80211_hdr *hdr = frame;
2138 cts->frame_control =
2139 cpu_to_le16(IEEE80211_FTYPE_CTL | IEEE80211_STYPE_CTS);
2140 cts->duration = ieee80211_ctstoself_duration(hw, vif,
2141 frame_len, frame_txctl);
2142 memcpy(cts->ra, hdr->addr1, sizeof(cts->ra));
2144 EXPORT_SYMBOL(ieee80211_ctstoself_get);
2147 ieee80211_get_buffered_bc(struct ieee80211_hw *hw,
2148 struct ieee80211_vif *vif)
2150 struct ieee80211_local *local = hw_to_local(hw);
2151 struct sk_buff *skb = NULL;
2152 struct sta_info *sta;
2153 struct ieee80211_tx_data tx;
2154 struct ieee80211_sub_if_data *sdata;
2155 struct ieee80211_if_ap *bss = NULL;
2156 struct beacon_data *beacon;
2157 struct ieee80211_tx_info *info;
2159 sdata = vif_to_sdata(vif);
2163 beacon = rcu_dereference(bss->beacon);
2165 if (sdata->vif.type != NL80211_IFTYPE_AP || !beacon || !beacon->head)
2168 if (bss->dtim_count != 0)
2169 goto out; /* send buffered bc/mc only after DTIM beacon */
2172 skb = skb_dequeue(&bss->ps_bc_buf);
2175 local->total_ps_buffered--;
2177 if (!skb_queue_empty(&bss->ps_bc_buf) && skb->len >= 2) {
2178 struct ieee80211_hdr *hdr =
2179 (struct ieee80211_hdr *) skb->data;
2180 /* more buffered multicast/broadcast frames ==> set
2181 * MoreData flag in IEEE 802.11 header to inform PS
2183 hdr->frame_control |=
2184 cpu_to_le16(IEEE80211_FCTL_MOREDATA);
2187 if (!ieee80211_tx_prepare(sdata, &tx, skb))
2189 dev_kfree_skb_any(skb);
2192 info = IEEE80211_SKB_CB(skb);
2195 tx.flags |= IEEE80211_TX_PS_BUFFERED;
2196 tx.channel = local->hw.conf.channel;
2197 info->band = tx.channel->band;
2199 if (invoke_tx_handlers(&tx))
2206 EXPORT_SYMBOL(ieee80211_get_buffered_bc);
2208 void ieee80211_tx_skb(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb,
2211 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
2212 skb_set_mac_header(skb, 0);
2213 skb_set_network_header(skb, 0);
2214 skb_set_transport_header(skb, 0);
2217 info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
2220 * The other path calling ieee80211_xmit is from the tasklet,
2221 * and while we can handle concurrent transmissions locking
2222 * requirements are that we do not come into tx with bhs on.
2225 ieee80211_xmit(sdata, skb);