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"
35 #define IEEE80211_TX_OK 0
36 #define IEEE80211_TX_AGAIN 1
37 #define IEEE80211_TX_PENDING 2
41 static __le16 ieee80211_duration(struct ieee80211_tx_data *tx, int group_addr,
44 int rate, mrate, erp, dur, i;
45 struct ieee80211_rate *txrate;
46 struct ieee80211_local *local = tx->local;
47 struct ieee80211_supported_band *sband;
48 struct ieee80211_hdr *hdr;
49 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
51 /* assume HW handles this */
52 if (info->control.rates[0].flags & IEEE80211_TX_RC_MCS)
56 if (WARN_ON_ONCE(info->control.rates[0].idx < 0))
59 sband = local->hw.wiphy->bands[tx->channel->band];
60 txrate = &sband->bitrates[info->control.rates[0].idx];
62 erp = txrate->flags & IEEE80211_RATE_ERP_G;
65 * data and mgmt (except PS Poll):
67 * - during contention period:
68 * if addr1 is group address: 0
69 * if more fragments = 0 and addr1 is individual address: time to
70 * transmit one ACK plus SIFS
71 * if more fragments = 1 and addr1 is individual address: time to
72 * transmit next fragment plus 2 x ACK plus 3 x SIFS
75 * - control response frame (CTS or ACK) shall be transmitted using the
76 * same rate as the immediately previous frame in the frame exchange
77 * sequence, if this rate belongs to the PHY mandatory rates, or else
78 * at the highest possible rate belonging to the PHY rates in the
81 hdr = (struct ieee80211_hdr *)tx->skb->data;
82 if (ieee80211_is_ctl(hdr->frame_control)) {
83 /* TODO: These control frames are not currently sent by
84 * mac80211, but should they be implemented, this function
85 * needs to be updated to support duration field calculation.
87 * RTS: time needed to transmit pending data/mgmt frame plus
88 * one CTS frame plus one ACK frame plus 3 x SIFS
89 * CTS: duration of immediately previous RTS minus time
90 * required to transmit CTS and its SIFS
91 * ACK: 0 if immediately previous directed data/mgmt had
92 * more=0, with more=1 duration in ACK frame is duration
93 * from previous frame minus time needed to transmit ACK
95 * PS Poll: BIT(15) | BIT(14) | aid
101 if (0 /* FIX: data/mgmt during CFP */)
102 return cpu_to_le16(32768);
104 if (group_addr) /* Group address as the destination - no ACK */
107 /* Individual destination address:
108 * IEEE 802.11, Ch. 9.6 (after IEEE 802.11g changes)
109 * CTS and ACK frames shall be transmitted using the highest rate in
110 * basic rate set that is less than or equal to the rate of the
111 * immediately previous frame and that is using the same modulation
112 * (CCK or OFDM). If no basic rate set matches with these requirements,
113 * the highest mandatory rate of the PHY that is less than or equal to
114 * the rate of the previous frame is used.
115 * Mandatory rates for IEEE 802.11g PHY: 1, 2, 5.5, 11, 6, 12, 24 Mbps
118 /* use lowest available if everything fails */
119 mrate = sband->bitrates[0].bitrate;
120 for (i = 0; i < sband->n_bitrates; i++) {
121 struct ieee80211_rate *r = &sband->bitrates[i];
123 if (r->bitrate > txrate->bitrate)
126 if (tx->sdata->vif.bss_conf.basic_rates & BIT(i))
129 switch (sband->band) {
130 case IEEE80211_BAND_2GHZ: {
132 if (tx->sdata->flags & IEEE80211_SDATA_OPERATING_GMODE)
133 flag = IEEE80211_RATE_MANDATORY_G;
135 flag = IEEE80211_RATE_MANDATORY_B;
140 case IEEE80211_BAND_5GHZ:
141 if (r->flags & IEEE80211_RATE_MANDATORY_A)
144 case IEEE80211_NUM_BANDS:
150 /* No matching basic rate found; use highest suitable mandatory
155 /* Time needed to transmit ACK
156 * (10 bytes + 4-byte FCS = 112 bits) plus SIFS; rounded up
157 * to closest integer */
159 dur = ieee80211_frame_duration(local, 10, rate, erp,
160 tx->sdata->vif.bss_conf.use_short_preamble);
163 /* Frame is fragmented: duration increases with time needed to
164 * transmit next fragment plus ACK and 2 x SIFS. */
165 dur *= 2; /* ACK + SIFS */
167 dur += ieee80211_frame_duration(local, next_frag_len,
168 txrate->bitrate, erp,
169 tx->sdata->vif.bss_conf.use_short_preamble);
172 return cpu_to_le16(dur);
175 static int inline is_ieee80211_device(struct ieee80211_local *local,
176 struct net_device *dev)
178 return local == wdev_priv(dev->ieee80211_ptr);
183 static ieee80211_tx_result debug_noinline
184 ieee80211_tx_h_check_assoc(struct ieee80211_tx_data *tx)
187 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
188 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
191 if (unlikely(info->flags & IEEE80211_TX_CTL_INJECTED))
194 if (unlikely(tx->local->sw_scanning) &&
195 !ieee80211_is_probe_req(hdr->frame_control) &&
196 !ieee80211_is_nullfunc(hdr->frame_control))
198 * When software scanning only nullfunc frames (to notify
199 * the sleep state to the AP) and probe requests (for the
200 * active scan) are allowed, all other frames should not be
201 * sent and we should not get here, but if we do
202 * nonetheless, drop them to avoid sending them
203 * off-channel. See the link below and
204 * ieee80211_start_scan() for more.
206 * http://article.gmane.org/gmane.linux.kernel.wireless.general/30089
210 if (tx->sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
213 if (tx->flags & IEEE80211_TX_PS_BUFFERED)
216 sta_flags = tx->sta ? get_sta_flags(tx->sta) : 0;
218 if (likely(tx->flags & IEEE80211_TX_UNICAST)) {
219 if (unlikely(!(sta_flags & WLAN_STA_ASSOC) &&
220 tx->sdata->vif.type != NL80211_IFTYPE_ADHOC &&
221 ieee80211_is_data(hdr->frame_control))) {
222 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
223 printk(KERN_DEBUG "%s: dropped data frame to not "
224 "associated station %pM\n",
225 tx->dev->name, hdr->addr1);
226 #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */
227 I802_DEBUG_INC(tx->local->tx_handlers_drop_not_assoc);
231 if (unlikely(ieee80211_is_data(hdr->frame_control) &&
232 tx->local->num_sta == 0 &&
233 tx->sdata->vif.type != NL80211_IFTYPE_ADHOC)) {
235 * No associated STAs - no need to send multicast
246 /* This function is called whenever the AP is about to exceed the maximum limit
247 * of buffered frames for power saving STAs. This situation should not really
248 * happen often during normal operation, so dropping the oldest buffered packet
249 * from each queue should be OK to make some room for new frames. */
250 static void purge_old_ps_buffers(struct ieee80211_local *local)
252 int total = 0, purged = 0;
254 struct ieee80211_sub_if_data *sdata;
255 struct sta_info *sta;
258 * virtual interfaces are protected by RCU
262 list_for_each_entry_rcu(sdata, &local->interfaces, list) {
263 struct ieee80211_if_ap *ap;
264 if (sdata->vif.type != NL80211_IFTYPE_AP)
267 skb = skb_dequeue(&ap->ps_bc_buf);
272 total += skb_queue_len(&ap->ps_bc_buf);
275 list_for_each_entry_rcu(sta, &local->sta_list, list) {
276 skb = skb_dequeue(&sta->ps_tx_buf);
281 total += skb_queue_len(&sta->ps_tx_buf);
286 local->total_ps_buffered = total;
287 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
288 printk(KERN_DEBUG "%s: PS buffers full - purged %d frames\n",
289 wiphy_name(local->hw.wiphy), purged);
293 static ieee80211_tx_result
294 ieee80211_tx_h_multicast_ps_buf(struct ieee80211_tx_data *tx)
296 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
297 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
300 * broadcast/multicast frame
302 * If any of the associated stations is in power save mode,
303 * the frame is buffered to be sent after DTIM beacon frame.
304 * This is done either by the hardware or us.
307 /* powersaving STAs only in AP/VLAN mode */
311 /* no buffering for ordered frames */
312 if (ieee80211_has_order(hdr->frame_control))
315 /* no stations in PS mode */
316 if (!atomic_read(&tx->sdata->bss->num_sta_ps))
319 /* buffered in mac80211 */
320 if (tx->local->hw.flags & IEEE80211_HW_HOST_BROADCAST_PS_BUFFERING) {
321 if (tx->local->total_ps_buffered >= TOTAL_MAX_TX_BUFFER)
322 purge_old_ps_buffers(tx->local);
323 if (skb_queue_len(&tx->sdata->bss->ps_bc_buf) >=
325 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
326 if (net_ratelimit()) {
327 printk(KERN_DEBUG "%s: BC TX buffer full - "
328 "dropping the oldest frame\n",
332 dev_kfree_skb(skb_dequeue(&tx->sdata->bss->ps_bc_buf));
334 tx->local->total_ps_buffered++;
335 skb_queue_tail(&tx->sdata->bss->ps_bc_buf, tx->skb);
339 /* buffered in hardware */
340 info->flags |= IEEE80211_TX_CTL_SEND_AFTER_DTIM;
345 static int ieee80211_use_mfp(__le16 fc, struct sta_info *sta,
348 if (!ieee80211_is_mgmt(fc))
351 if (sta == NULL || !test_sta_flags(sta, WLAN_STA_MFP))
354 if (!ieee80211_is_robust_mgmt_frame((struct ieee80211_hdr *)
361 static ieee80211_tx_result
362 ieee80211_tx_h_unicast_ps_buf(struct ieee80211_tx_data *tx)
364 struct sta_info *sta = tx->sta;
365 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
366 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
369 if (unlikely(!sta || ieee80211_is_probe_resp(hdr->frame_control)))
372 staflags = get_sta_flags(sta);
374 if (unlikely((staflags & WLAN_STA_PS) &&
375 !(staflags & WLAN_STA_PSPOLL))) {
376 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
377 printk(KERN_DEBUG "STA %pM aid %d: PS buffer (entries "
379 sta->sta.addr, sta->sta.aid,
380 skb_queue_len(&sta->ps_tx_buf));
381 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
382 if (tx->local->total_ps_buffered >= TOTAL_MAX_TX_BUFFER)
383 purge_old_ps_buffers(tx->local);
384 if (skb_queue_len(&sta->ps_tx_buf) >= STA_MAX_TX_BUFFER) {
385 struct sk_buff *old = skb_dequeue(&sta->ps_tx_buf);
386 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
387 if (net_ratelimit()) {
388 printk(KERN_DEBUG "%s: STA %pM TX "
389 "buffer full - dropping oldest frame\n",
390 tx->dev->name, sta->sta.addr);
395 tx->local->total_ps_buffered++;
397 /* Queue frame to be sent after STA sends an PS Poll frame */
398 if (skb_queue_empty(&sta->ps_tx_buf))
399 sta_info_set_tim_bit(sta);
401 info->control.jiffies = jiffies;
402 skb_queue_tail(&sta->ps_tx_buf, tx->skb);
405 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
406 else if (unlikely(test_sta_flags(sta, WLAN_STA_PS))) {
407 printk(KERN_DEBUG "%s: STA %pM in PS mode, but pspoll "
408 "set -> send frame\n", tx->dev->name,
411 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
412 clear_sta_flags(sta, WLAN_STA_PSPOLL);
417 static ieee80211_tx_result debug_noinline
418 ieee80211_tx_h_ps_buf(struct ieee80211_tx_data *tx)
420 if (unlikely(tx->flags & IEEE80211_TX_PS_BUFFERED))
423 if (tx->flags & IEEE80211_TX_UNICAST)
424 return ieee80211_tx_h_unicast_ps_buf(tx);
426 return ieee80211_tx_h_multicast_ps_buf(tx);
429 static ieee80211_tx_result debug_noinline
430 ieee80211_tx_h_select_key(struct ieee80211_tx_data *tx)
432 struct ieee80211_key *key;
433 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
434 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
436 if (unlikely(tx->skb->do_not_encrypt))
438 else if (tx->sta && (key = rcu_dereference(tx->sta->key)))
440 else if (ieee80211_is_mgmt(hdr->frame_control) &&
441 (key = rcu_dereference(tx->sdata->default_mgmt_key)))
443 else if ((key = rcu_dereference(tx->sdata->default_key)))
445 else if (tx->sdata->drop_unencrypted &&
446 (tx->skb->protocol != cpu_to_be16(ETH_P_PAE)) &&
447 !(info->flags & IEEE80211_TX_CTL_INJECTED) &&
448 (!ieee80211_is_robust_mgmt_frame(hdr) ||
449 (ieee80211_is_action(hdr->frame_control) &&
450 tx->sta && test_sta_flags(tx->sta, WLAN_STA_MFP)))) {
451 I802_DEBUG_INC(tx->local->tx_handlers_drop_unencrypted);
457 tx->key->tx_rx_count++;
458 /* TODO: add threshold stuff again */
460 switch (tx->key->conf.alg) {
462 if (ieee80211_is_auth(hdr->frame_control))
465 if (!ieee80211_is_data_present(hdr->frame_control))
469 if (!ieee80211_is_data_present(hdr->frame_control) &&
470 !ieee80211_use_mfp(hdr->frame_control, tx->sta,
475 if (!ieee80211_is_mgmt(hdr->frame_control))
481 if (!tx->key || !(tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))
482 tx->skb->do_not_encrypt = 1;
487 static ieee80211_tx_result debug_noinline
488 ieee80211_tx_h_rate_ctrl(struct ieee80211_tx_data *tx)
490 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
491 struct ieee80211_hdr *hdr = (void *)tx->skb->data;
492 struct ieee80211_supported_band *sband;
493 struct ieee80211_rate *rate;
495 bool inval = false, rts = false, short_preamble = false;
496 struct ieee80211_tx_rate_control txrc;
498 memset(&txrc, 0, sizeof(txrc));
500 sband = tx->local->hw.wiphy->bands[tx->channel->band];
502 len = min_t(int, tx->skb->len + FCS_LEN,
503 tx->local->fragmentation_threshold);
505 /* set up the tx rate control struct we give the RC algo */
506 txrc.hw = local_to_hw(tx->local);
508 txrc.bss_conf = &tx->sdata->vif.bss_conf;
510 txrc.reported_rate.idx = -1;
511 txrc.max_rate_idx = tx->sdata->max_ratectrl_rateidx;
513 /* set up RTS protection if desired */
514 if (tx->local->rts_threshold < IEEE80211_MAX_RTS_THRESHOLD &&
515 len > tx->local->rts_threshold) {
516 txrc.rts = rts = true;
520 * Use short preamble if the BSS can handle it, but not for
521 * management frames unless we know the receiver can handle
522 * that -- the management frame might be to a station that
523 * just wants a probe response.
525 if (tx->sdata->vif.bss_conf.use_short_preamble &&
526 (ieee80211_is_data(hdr->frame_control) ||
527 (tx->sta && test_sta_flags(tx->sta, WLAN_STA_SHORT_PREAMBLE))))
528 txrc.short_preamble = short_preamble = true;
531 rate_control_get_rate(tx->sdata, tx->sta, &txrc);
533 if (unlikely(info->control.rates[0].idx < 0))
536 if (txrc.reported_rate.idx < 0)
537 txrc.reported_rate = info->control.rates[0];
540 tx->sta->last_tx_rate = txrc.reported_rate;
542 if (unlikely(!info->control.rates[0].count))
543 info->control.rates[0].count = 1;
545 if (is_multicast_ether_addr(hdr->addr1)) {
547 * XXX: verify the rate is in the basic rateset
553 * set up the RTS/CTS rate as the fastest basic rate
554 * that is not faster than the data rate
556 * XXX: Should this check all retry rates?
558 if (!(info->control.rates[0].flags & IEEE80211_TX_RC_MCS)) {
561 rate = &sband->bitrates[info->control.rates[0].idx];
563 for (i = 0; i < sband->n_bitrates; i++) {
564 /* must be a basic rate */
565 if (!(tx->sdata->vif.bss_conf.basic_rates & BIT(i)))
567 /* must not be faster than the data rate */
568 if (sband->bitrates[i].bitrate > rate->bitrate)
571 if (sband->bitrates[baserate].bitrate <
572 sband->bitrates[i].bitrate)
576 info->control.rts_cts_rate_idx = baserate;
579 for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) {
581 * make sure there's no valid rate following
582 * an invalid one, just in case drivers don't
583 * take the API seriously to stop at -1.
586 info->control.rates[i].idx = -1;
589 if (info->control.rates[i].idx < 0) {
595 * For now assume MCS is already set up correctly, this
598 if (info->control.rates[i].flags & IEEE80211_TX_RC_MCS) {
599 WARN_ON(info->control.rates[i].idx > 76);
603 /* set up RTS protection if desired */
605 info->control.rates[i].flags |=
606 IEEE80211_TX_RC_USE_RTS_CTS;
609 if (WARN_ON_ONCE(info->control.rates[i].idx >=
610 sband->n_bitrates)) {
611 info->control.rates[i].idx = -1;
615 rate = &sband->bitrates[info->control.rates[i].idx];
617 /* set up short preamble */
618 if (short_preamble &&
619 rate->flags & IEEE80211_RATE_SHORT_PREAMBLE)
620 info->control.rates[i].flags |=
621 IEEE80211_TX_RC_USE_SHORT_PREAMBLE;
623 /* set up G protection */
624 if (!rts && tx->sdata->vif.bss_conf.use_cts_prot &&
625 rate->flags & IEEE80211_RATE_ERP_G)
626 info->control.rates[i].flags |=
627 IEEE80211_TX_RC_USE_CTS_PROTECT;
633 static ieee80211_tx_result debug_noinline
634 ieee80211_tx_h_misc(struct ieee80211_tx_data *tx)
636 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
639 info->control.sta = &tx->sta->sta;
644 static ieee80211_tx_result debug_noinline
645 ieee80211_tx_h_sequence(struct ieee80211_tx_data *tx)
647 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
648 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
654 * Packet injection may want to control the sequence
655 * number, if we have no matching interface then we
656 * neither assign one ourselves nor ask the driver to.
658 if (unlikely(!info->control.vif))
661 if (unlikely(ieee80211_is_ctl(hdr->frame_control)))
664 if (ieee80211_hdrlen(hdr->frame_control) < 24)
668 * Anything but QoS data that has a sequence number field
669 * (is long enough) gets a sequence number from the global
672 if (!ieee80211_is_data_qos(hdr->frame_control)) {
673 /* driver should assign sequence number */
674 info->flags |= IEEE80211_TX_CTL_ASSIGN_SEQ;
675 /* for pure STA mode without beacons, we can do it */
676 hdr->seq_ctrl = cpu_to_le16(tx->sdata->sequence_number);
677 tx->sdata->sequence_number += 0x10;
678 tx->sdata->sequence_number &= IEEE80211_SCTL_SEQ;
683 * This should be true for injected/management frames only, for
684 * management frames we have set the IEEE80211_TX_CTL_ASSIGN_SEQ
685 * above since they are not QoS-data frames.
690 /* include per-STA, per-TID sequence counter */
692 qc = ieee80211_get_qos_ctl(hdr);
693 tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
694 seq = &tx->sta->tid_seq[tid];
696 hdr->seq_ctrl = cpu_to_le16(*seq);
698 /* Increase the sequence number. */
699 *seq = (*seq + 0x10) & IEEE80211_SCTL_SEQ;
704 static int ieee80211_fragment(struct ieee80211_local *local,
705 struct sk_buff *skb, int hdrlen,
708 struct sk_buff *tail = skb, *tmp;
709 int per_fragm = frag_threshold - hdrlen - FCS_LEN;
710 int pos = hdrlen + per_fragm;
711 int rem = skb->len - hdrlen - per_fragm;
713 if (WARN_ON(rem < 0))
717 int fraglen = per_fragm;
722 tmp = dev_alloc_skb(local->tx_headroom +
724 IEEE80211_ENCRYPT_HEADROOM +
725 IEEE80211_ENCRYPT_TAILROOM);
730 skb_reserve(tmp, local->tx_headroom +
731 IEEE80211_ENCRYPT_HEADROOM);
732 /* copy control information */
733 memcpy(tmp->cb, skb->cb, sizeof(tmp->cb));
734 skb_copy_queue_mapping(tmp, skb);
735 tmp->priority = skb->priority;
736 tmp->do_not_encrypt = skb->do_not_encrypt;
740 /* copy header and data */
741 memcpy(skb_put(tmp, hdrlen), skb->data, hdrlen);
742 memcpy(skb_put(tmp, fraglen), skb->data + pos, fraglen);
747 skb->len = hdrlen + per_fragm;
751 static ieee80211_tx_result debug_noinline
752 ieee80211_tx_h_fragment(struct ieee80211_tx_data *tx)
754 struct sk_buff *skb = tx->skb;
755 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
756 struct ieee80211_hdr *hdr = (void *)skb->data;
757 int frag_threshold = tx->local->fragmentation_threshold;
761 if (!(tx->flags & IEEE80211_TX_FRAGMENTED))
765 * Warn when submitting a fragmented A-MPDU frame and drop it.
766 * This scenario is handled in __ieee80211_tx_prepare but extra
767 * caution taken here as fragmented ampdu may cause Tx stop.
769 if (WARN_ON(info->flags & IEEE80211_TX_CTL_AMPDU))
772 hdrlen = ieee80211_hdrlen(hdr->frame_control);
774 /* internal error, why is TX_FRAGMENTED set? */
775 if (WARN_ON(skb->len <= frag_threshold))
779 * Now fragment the frame. This will allocate all the fragments and
780 * chain them (using skb as the first fragment) to skb->next.
781 * During transmission, we will remove the successfully transmitted
782 * fragments from this list. When the low-level driver rejects one
783 * of the fragments then we will simply pretend to accept the skb
784 * but store it away as pending.
786 if (ieee80211_fragment(tx->local, skb, hdrlen, frag_threshold))
789 /* update duration/seq/flags of fragments */
793 const __le16 morefrags = cpu_to_le16(IEEE80211_FCTL_MOREFRAGS);
795 hdr = (void *)skb->data;
796 info = IEEE80211_SKB_CB(skb);
799 hdr->frame_control |= morefrags;
800 next_len = skb->next->len;
802 * No multi-rate retries for fragmented frames, that
803 * would completely throw off the NAV at other STAs.
805 info->control.rates[1].idx = -1;
806 info->control.rates[2].idx = -1;
807 info->control.rates[3].idx = -1;
808 info->control.rates[4].idx = -1;
809 BUILD_BUG_ON(IEEE80211_TX_MAX_RATES != 5);
810 info->flags &= ~IEEE80211_TX_CTL_RATE_CTRL_PROBE;
812 hdr->frame_control &= ~morefrags;
815 hdr->duration_id = ieee80211_duration(tx, 0, next_len);
816 hdr->seq_ctrl |= cpu_to_le16(fragnum & IEEE80211_SCTL_FRAG);
818 } while ((skb = skb->next));
823 static ieee80211_tx_result debug_noinline
824 ieee80211_tx_h_encrypt(struct ieee80211_tx_data *tx)
829 switch (tx->key->conf.alg) {
831 return ieee80211_crypto_wep_encrypt(tx);
833 return ieee80211_crypto_tkip_encrypt(tx);
835 return ieee80211_crypto_ccmp_encrypt(tx);
837 return ieee80211_crypto_aes_cmac_encrypt(tx);
845 static ieee80211_tx_result debug_noinline
846 ieee80211_tx_h_calculate_duration(struct ieee80211_tx_data *tx)
848 struct sk_buff *skb = tx->skb;
849 struct ieee80211_hdr *hdr;
854 hdr = (void *) skb->data;
855 next_len = skb->next ? skb->next->len : 0;
856 group_addr = is_multicast_ether_addr(hdr->addr1);
859 ieee80211_duration(tx, group_addr, next_len);
860 } while ((skb = skb->next));
865 static ieee80211_tx_result debug_noinline
866 ieee80211_tx_h_stats(struct ieee80211_tx_data *tx)
868 struct sk_buff *skb = tx->skb;
873 tx->sta->tx_packets++;
875 tx->sta->tx_fragments++;
876 tx->sta->tx_bytes += skb->len;
877 } while ((skb = skb->next));
882 /* actual transmit path */
885 * deal with packet injection down monitor interface
886 * with Radiotap Header -- only called for monitor mode interface
888 static ieee80211_tx_result
889 __ieee80211_parse_tx_radiotap(struct ieee80211_tx_data *tx,
893 * this is the moment to interpret and discard the radiotap header that
894 * must be at the start of the packet injected in Monitor mode
896 * Need to take some care with endian-ness since radiotap
897 * args are little-endian
900 struct ieee80211_radiotap_iterator iterator;
901 struct ieee80211_radiotap_header *rthdr =
902 (struct ieee80211_radiotap_header *) skb->data;
903 struct ieee80211_supported_band *sband;
904 int ret = ieee80211_radiotap_iterator_init(&iterator, rthdr, skb->len);
906 sband = tx->local->hw.wiphy->bands[tx->channel->band];
908 skb->do_not_encrypt = 1;
909 tx->flags &= ~IEEE80211_TX_FRAGMENTED;
912 * for every radiotap entry that is present
913 * (ieee80211_radiotap_iterator_next returns -ENOENT when no more
914 * entries present, or -EINVAL on error)
918 ret = ieee80211_radiotap_iterator_next(&iterator);
923 /* see if this argument is something we can use */
924 switch (iterator.this_arg_index) {
926 * You must take care when dereferencing iterator.this_arg
927 * for multibyte types... the pointer is not aligned. Use
928 * get_unaligned((type *)iterator.this_arg) to dereference
929 * iterator.this_arg for type "type" safely on all arches.
931 case IEEE80211_RADIOTAP_FLAGS:
932 if (*iterator.this_arg & IEEE80211_RADIOTAP_F_FCS) {
934 * this indicates that the skb we have been
935 * handed has the 32-bit FCS CRC at the end...
936 * we should react to that by snipping it off
937 * because it will be recomputed and added
940 if (skb->len < (iterator.max_length + FCS_LEN))
943 skb_trim(skb, skb->len - FCS_LEN);
945 if (*iterator.this_arg & IEEE80211_RADIOTAP_F_WEP)
946 tx->skb->do_not_encrypt = 0;
947 if (*iterator.this_arg & IEEE80211_RADIOTAP_F_FRAG)
948 tx->flags |= IEEE80211_TX_FRAGMENTED;
952 * Please update the file
953 * Documentation/networking/mac80211-injection.txt
954 * when parsing new fields here.
962 if (ret != -ENOENT) /* ie, if we didn't simply run out of fields */
966 * remove the radiotap header
967 * iterator->max_length was sanity-checked against
968 * skb->len by iterator init
970 skb_pull(skb, iterator.max_length);
978 static ieee80211_tx_result
979 __ieee80211_tx_prepare(struct ieee80211_tx_data *tx,
981 struct net_device *dev)
983 struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
984 struct ieee80211_hdr *hdr;
985 struct ieee80211_sub_if_data *sdata;
986 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
991 memset(tx, 0, sizeof(*tx));
993 tx->dev = dev; /* use original interface */
995 tx->sdata = IEEE80211_DEV_TO_SUB_IF(dev);
996 tx->channel = local->hw.conf.channel;
998 * Set this flag (used below to indicate "automatic fragmentation"),
999 * it will be cleared/left by radiotap as desired.
1001 tx->flags |= IEEE80211_TX_FRAGMENTED;
1003 /* process and remove the injection radiotap header */
1004 sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1005 if (unlikely(info->flags & IEEE80211_TX_CTL_INJECTED)) {
1006 if (__ieee80211_parse_tx_radiotap(tx, skb) == TX_DROP)
1010 * __ieee80211_parse_tx_radiotap has now removed
1011 * the radiotap header that was present and pre-filled
1012 * 'tx' with tx control information.
1017 * If this flag is set to true anywhere, and we get here,
1018 * we are doing the needed processing, so remove the flag
1021 info->flags &= ~IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1023 hdr = (struct ieee80211_hdr *) skb->data;
1025 tx->sta = sta_info_get(local, hdr->addr1);
1027 if (tx->sta && ieee80211_is_data_qos(hdr->frame_control) &&
1028 (local->hw.flags & IEEE80211_HW_AMPDU_AGGREGATION)) {
1029 unsigned long flags;
1030 struct tid_ampdu_tx *tid_tx;
1032 qc = ieee80211_get_qos_ctl(hdr);
1033 tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
1035 spin_lock_irqsave(&tx->sta->lock, flags);
1037 * XXX: This spinlock could be fairly expensive, but see the
1038 * comment in agg-tx.c:ieee80211_agg_tx_operational().
1039 * One way to solve this would be to do something RCU-like
1040 * for managing the tid_tx struct and using atomic bitops
1041 * for the actual state -- by introducing an actual
1042 * 'operational' bit that would be possible. It would
1043 * require changing ieee80211_agg_tx_operational() to
1044 * set that bit, and changing the way tid_tx is managed
1045 * everywhere, including races between that bit and
1046 * tid_tx going away (tid_tx being added can be easily
1047 * committed to memory before the 'operational' bit).
1049 tid_tx = tx->sta->ampdu_mlme.tid_tx[tid];
1050 state = &tx->sta->ampdu_mlme.tid_state_tx[tid];
1051 if (*state == HT_AGG_STATE_OPERATIONAL) {
1052 info->flags |= IEEE80211_TX_CTL_AMPDU;
1053 } else if (*state != HT_AGG_STATE_IDLE) {
1056 info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1057 __skb_queue_tail(&tid_tx->pending, skb);
1059 spin_unlock_irqrestore(&tx->sta->lock, flags);
1061 if (unlikely(queued))
1065 if (is_multicast_ether_addr(hdr->addr1)) {
1066 tx->flags &= ~IEEE80211_TX_UNICAST;
1067 info->flags |= IEEE80211_TX_CTL_NO_ACK;
1069 tx->flags |= IEEE80211_TX_UNICAST;
1070 info->flags &= ~IEEE80211_TX_CTL_NO_ACK;
1073 if (tx->flags & IEEE80211_TX_FRAGMENTED) {
1074 if ((tx->flags & IEEE80211_TX_UNICAST) &&
1075 skb->len + FCS_LEN > local->fragmentation_threshold &&
1076 !(info->flags & IEEE80211_TX_CTL_AMPDU))
1077 tx->flags |= IEEE80211_TX_FRAGMENTED;
1079 tx->flags &= ~IEEE80211_TX_FRAGMENTED;
1083 info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT;
1084 else if (test_and_clear_sta_flags(tx->sta, WLAN_STA_CLEAR_PS_FILT))
1085 info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT;
1087 hdrlen = ieee80211_hdrlen(hdr->frame_control);
1088 if (skb->len > hdrlen + sizeof(rfc1042_header) + 2) {
1089 u8 *pos = &skb->data[hdrlen + sizeof(rfc1042_header)];
1090 tx->ethertype = (pos[0] << 8) | pos[1];
1092 info->flags |= IEEE80211_TX_CTL_FIRST_FRAGMENT;
1098 * NB: @tx is uninitialised when passed in here
1100 static int ieee80211_tx_prepare(struct ieee80211_local *local,
1101 struct ieee80211_tx_data *tx,
1102 struct sk_buff *skb)
1104 struct net_device *dev;
1106 dev = dev_get_by_index(&init_net, skb->iif);
1107 if (unlikely(dev && !is_ieee80211_device(local, dev))) {
1114 * initialises tx with control
1116 * return value is safe to ignore here because this function
1117 * can only be invoked for multicast frames
1121 __ieee80211_tx_prepare(tx, skb, dev);
1126 static int __ieee80211_tx(struct ieee80211_local *local,
1127 struct sk_buff **skbp,
1128 struct sta_info *sta)
1130 struct sk_buff *skb = *skbp, *next;
1131 struct ieee80211_tx_info *info;
1135 local->mdev->trans_start = jiffies;
1138 if (ieee80211_queue_stopped(&local->hw,
1139 skb_get_queue_mapping(skb)))
1140 return IEEE80211_TX_PENDING;
1142 info = IEEE80211_SKB_CB(skb);
1145 info->flags &= ~(IEEE80211_TX_CTL_CLEAR_PS_FILT |
1146 IEEE80211_TX_CTL_FIRST_FRAGMENT);
1149 * Internally, we need to have the queue mapping point to
1150 * the real AC queue, not the virtual A-MPDU queue. This
1151 * now finally sets the queue to what the driver wants.
1152 * We will later move this down into the only driver that
1153 * needs it, iwlwifi.
1155 if (sta && local->hw.ampdu_queues &&
1156 info->flags & IEEE80211_TX_CTL_AMPDU) {
1157 unsigned long flags;
1158 u8 *qc = ieee80211_get_qos_ctl((void *) skb->data);
1159 int tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
1161 spin_lock_irqsave(&sta->lock, flags);
1162 skb_set_queue_mapping(skb, local->hw.queues +
1163 sta->tid_to_tx_q[tid]);
1164 spin_unlock_irqrestore(&sta->lock, flags);
1169 ret = local->ops->tx(local_to_hw(local), skb);
1170 if (WARN_ON(ret != NETDEV_TX_OK && skb->len != len)) {
1174 if (ret != NETDEV_TX_OK)
1175 return IEEE80211_TX_AGAIN;
1177 ieee80211_led_tx(local, 1);
1181 return IEEE80211_TX_OK;
1185 * Invoke TX handlers, return 0 on success and non-zero if the
1186 * frame was dropped or queued.
1188 static int invoke_tx_handlers(struct ieee80211_tx_data *tx)
1190 struct sk_buff *skb = tx->skb;
1191 ieee80211_tx_result res = TX_DROP;
1193 #define CALL_TXH(txh) \
1195 if (res != TX_CONTINUE) \
1198 CALL_TXH(ieee80211_tx_h_check_assoc)
1199 CALL_TXH(ieee80211_tx_h_ps_buf)
1200 CALL_TXH(ieee80211_tx_h_select_key)
1201 CALL_TXH(ieee80211_tx_h_michael_mic_add)
1202 CALL_TXH(ieee80211_tx_h_rate_ctrl)
1203 CALL_TXH(ieee80211_tx_h_misc)
1204 CALL_TXH(ieee80211_tx_h_sequence)
1205 CALL_TXH(ieee80211_tx_h_fragment)
1206 /* handlers after fragment must be aware of tx info fragmentation! */
1207 CALL_TXH(ieee80211_tx_h_encrypt)
1208 CALL_TXH(ieee80211_tx_h_calculate_duration)
1209 CALL_TXH(ieee80211_tx_h_stats)
1213 if (unlikely(res == TX_DROP)) {
1214 I802_DEBUG_INC(tx->local->tx_handlers_drop);
1216 struct sk_buff *next;
1223 } else if (unlikely(res == TX_QUEUED)) {
1224 I802_DEBUG_INC(tx->local->tx_handlers_queued);
1231 static void ieee80211_tx(struct net_device *dev, struct sk_buff *skb,
1234 struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
1235 struct sta_info *sta;
1236 struct ieee80211_tx_data tx;
1237 ieee80211_tx_result res_prepare;
1238 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1239 struct sk_buff *next;
1240 unsigned long flags;
1244 queue = skb_get_queue_mapping(skb);
1246 WARN_ON(!txpending && !skb_queue_empty(&local->pending[queue]));
1248 if (unlikely(skb->len < 10)) {
1255 /* initialises tx */
1256 res_prepare = __ieee80211_tx_prepare(&tx, skb, dev);
1258 if (unlikely(res_prepare == TX_DROP)) {
1262 } else if (unlikely(res_prepare == TX_QUEUED)) {
1268 tx.channel = local->hw.conf.channel;
1269 info->band = tx.channel->band;
1271 if (invoke_tx_handlers(&tx))
1276 ret = __ieee80211_tx(local, &tx.skb, tx.sta);
1278 case IEEE80211_TX_OK:
1280 case IEEE80211_TX_AGAIN:
1282 * Since there are no fragmented frames on A-MPDU
1283 * queues, there's no reason for a driver to reject
1284 * a frame there, warn and drop it.
1286 if (WARN_ON(info->flags & IEEE80211_TX_CTL_AMPDU))
1289 case IEEE80211_TX_PENDING:
1292 spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
1294 if (__netif_subqueue_stopped(local->mdev, queue)) {
1298 if (unlikely(txpending))
1299 skb_queue_head(&local->pending[queue],
1302 skb_queue_tail(&local->pending[queue],
1304 } while ((skb = next));
1307 * Make sure nobody will enable the queue on us
1308 * (without going through the tasklet) nor disable the
1309 * netdev queue underneath the pending handling code.
1311 __set_bit(IEEE80211_QUEUE_STOP_REASON_PENDING,
1312 &local->queue_stop_reasons[queue]);
1314 spin_unlock_irqrestore(&local->queue_stop_reason_lock,
1317 spin_unlock_irqrestore(&local->queue_stop_reason_lock,
1321 if (WARN(retries > 10, "tx refused but queue active"))
1341 /* device xmit handlers */
1343 static int ieee80211_skb_resize(struct ieee80211_local *local,
1344 struct sk_buff *skb,
1345 int head_need, bool may_encrypt)
1350 * This could be optimised, devices that do full hardware
1351 * crypto (including TKIP MMIC) need no tailroom... But we
1352 * have no drivers for such devices currently.
1355 tail_need = IEEE80211_ENCRYPT_TAILROOM;
1356 tail_need -= skb_tailroom(skb);
1357 tail_need = max_t(int, tail_need, 0);
1360 if (head_need || tail_need) {
1361 /* Sorry. Can't account for this any more */
1365 if (skb_header_cloned(skb))
1366 I802_DEBUG_INC(local->tx_expand_skb_head_cloned);
1368 I802_DEBUG_INC(local->tx_expand_skb_head);
1370 if (pskb_expand_head(skb, head_need, tail_need, GFP_ATOMIC)) {
1371 printk(KERN_DEBUG "%s: failed to reallocate TX buffer\n",
1372 wiphy_name(local->hw.wiphy));
1376 /* update truesize too */
1377 skb->truesize += head_need + tail_need;
1382 int ieee80211_master_start_xmit(struct sk_buff *skb, struct net_device *dev)
1384 struct ieee80211_master_priv *mpriv = netdev_priv(dev);
1385 struct ieee80211_local *local = mpriv->local;
1386 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1387 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1388 struct net_device *odev = NULL;
1389 struct ieee80211_sub_if_data *osdata;
1396 } monitor_iface = NOT_MONITOR;
1399 odev = dev_get_by_index(&init_net, skb->iif);
1400 if (unlikely(odev && !is_ieee80211_device(local, odev))) {
1404 if (unlikely(!odev)) {
1405 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
1406 printk(KERN_DEBUG "%s: Discarded packet with nonexistent "
1407 "originating device\n", dev->name);
1410 return NETDEV_TX_OK;
1413 if ((local->hw.flags & IEEE80211_HW_PS_NULLFUNC_STACK) &&
1414 local->hw.conf.dynamic_ps_timeout > 0) {
1415 if (local->hw.conf.flags & IEEE80211_CONF_PS) {
1416 ieee80211_stop_queues_by_reason(&local->hw,
1417 IEEE80211_QUEUE_STOP_REASON_PS);
1418 queue_work(local->hw.workqueue,
1419 &local->dynamic_ps_disable_work);
1422 mod_timer(&local->dynamic_ps_timer, jiffies +
1423 msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout));
1426 memset(info, 0, sizeof(*info));
1428 info->flags |= IEEE80211_TX_CTL_REQ_TX_STATUS;
1430 osdata = IEEE80211_DEV_TO_SUB_IF(odev);
1432 if (ieee80211_vif_is_mesh(&osdata->vif) &&
1433 ieee80211_is_data(hdr->frame_control)) {
1434 if (is_multicast_ether_addr(hdr->addr3))
1435 memcpy(hdr->addr1, hdr->addr3, ETH_ALEN);
1437 if (mesh_nexthop_lookup(skb, osdata)) {
1439 return NETDEV_TX_OK;
1441 if (memcmp(odev->dev_addr, hdr->addr4, ETH_ALEN) != 0)
1442 IEEE80211_IFSTA_MESH_CTR_INC(&osdata->u.mesh,
1444 } else if (unlikely(osdata->vif.type == NL80211_IFTYPE_MONITOR)) {
1445 struct ieee80211_sub_if_data *sdata;
1449 info->flags |= IEEE80211_TX_CTL_INJECTED;
1450 monitor_iface = UNKNOWN_ADDRESS;
1452 len_rthdr = ieee80211_get_radiotap_len(skb->data);
1453 hdr = (struct ieee80211_hdr *)skb->data + len_rthdr;
1454 hdrlen = ieee80211_hdrlen(hdr->frame_control);
1456 /* check the header is complete in the frame */
1457 if (likely(skb->len >= len_rthdr + hdrlen)) {
1459 * We process outgoing injected frames that have a
1460 * local address we handle as though they are our
1462 * This code here isn't entirely correct, the local
1463 * MAC address is not necessarily enough to find
1464 * the interface to use; for that proper VLAN/WDS
1465 * support we will need a different mechanism.
1469 list_for_each_entry_rcu(sdata, &local->interfaces,
1471 if (!netif_running(sdata->dev))
1473 if (sdata->vif.type != NL80211_IFTYPE_AP)
1475 if (compare_ether_addr(sdata->dev->dev_addr,
1477 dev_hold(sdata->dev);
1481 skb->iif = sdata->dev->ifindex;
1482 monitor_iface = FOUND_SDATA;
1490 may_encrypt = !skb->do_not_encrypt;
1492 headroom = osdata->local->tx_headroom;
1494 headroom += IEEE80211_ENCRYPT_HEADROOM;
1495 headroom -= skb_headroom(skb);
1496 headroom = max_t(int, 0, headroom);
1498 if (ieee80211_skb_resize(osdata->local, skb, headroom, may_encrypt)) {
1501 return NETDEV_TX_OK;
1504 if (osdata->vif.type == NL80211_IFTYPE_AP_VLAN)
1505 osdata = container_of(osdata->bss,
1506 struct ieee80211_sub_if_data,
1508 if (likely(monitor_iface != UNKNOWN_ADDRESS))
1509 info->control.vif = &osdata->vif;
1511 ieee80211_tx(odev, skb, false);
1514 return NETDEV_TX_OK;
1517 int ieee80211_monitor_start_xmit(struct sk_buff *skb,
1518 struct net_device *dev)
1520 struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
1521 struct ieee80211_channel *chan = local->hw.conf.channel;
1522 struct ieee80211_radiotap_header *prthdr =
1523 (struct ieee80211_radiotap_header *)skb->data;
1527 * Frame injection is not allowed if beaconing is not allowed
1528 * or if we need radar detection. Beaconing is usually not allowed when
1529 * the mode or operation (Adhoc, AP, Mesh) does not support DFS.
1530 * Passive scan is also used in world regulatory domains where
1531 * your country is not known and as such it should be treated as
1532 * NO TX unless the channel is explicitly allowed in which case
1533 * your current regulatory domain would not have the passive scan
1536 * Since AP mode uses monitor interfaces to inject/TX management
1537 * frames we can make AP mode the exception to this rule once it
1538 * supports radar detection as its implementation can deal with
1539 * radar detection by itself. We can do that later by adding a
1540 * monitor flag interfaces used for AP support.
1542 if ((chan->flags & (IEEE80211_CHAN_NO_IBSS | IEEE80211_CHAN_RADAR |
1543 IEEE80211_CHAN_PASSIVE_SCAN)))
1546 /* check for not even having the fixed radiotap header part */
1547 if (unlikely(skb->len < sizeof(struct ieee80211_radiotap_header)))
1548 goto fail; /* too short to be possibly valid */
1550 /* is it a header version we can trust to find length from? */
1551 if (unlikely(prthdr->it_version))
1552 goto fail; /* only version 0 is supported */
1554 /* then there must be a radiotap header with a length we can use */
1555 len_rthdr = ieee80211_get_radiotap_len(skb->data);
1557 /* does the skb contain enough to deliver on the alleged length? */
1558 if (unlikely(skb->len < len_rthdr))
1559 goto fail; /* skb too short for claimed rt header extent */
1561 skb->dev = local->mdev;
1563 /* needed because we set skb device to master */
1564 skb->iif = dev->ifindex;
1566 /* sometimes we do encrypt injected frames, will be fixed
1567 * up in radiotap parser if not wanted */
1568 skb->do_not_encrypt = 0;
1571 * fix up the pointers accounting for the radiotap
1572 * header still being in there. We are being given
1573 * a precooked IEEE80211 header so no need for
1576 skb_set_mac_header(skb, len_rthdr);
1578 * these are just fixed to the end of the rt area since we
1579 * don't have any better information and at this point, nobody cares
1581 skb_set_network_header(skb, len_rthdr);
1582 skb_set_transport_header(skb, len_rthdr);
1584 /* pass the radiotap header up to the next stage intact */
1585 dev_queue_xmit(skb);
1586 return NETDEV_TX_OK;
1590 return NETDEV_TX_OK; /* meaning, we dealt with the skb */
1594 * ieee80211_subif_start_xmit - netif start_xmit function for Ethernet-type
1595 * subinterfaces (wlan#, WDS, and VLAN interfaces)
1596 * @skb: packet to be sent
1597 * @dev: incoming interface
1599 * Returns: 0 on success (and frees skb in this case) or 1 on failure (skb will
1600 * not be freed, and caller is responsible for either retrying later or freeing
1603 * This function takes in an Ethernet header and encapsulates it with suitable
1604 * IEEE 802.11 header based on which interface the packet is coming in. The
1605 * encapsulated packet will then be passed to master interface, wlan#.11, for
1606 * transmission (through low-level driver).
1608 int ieee80211_subif_start_xmit(struct sk_buff *skb,
1609 struct net_device *dev)
1611 struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1612 struct ieee80211_local *local = sdata->local;
1613 int ret = 1, head_need;
1614 u16 ethertype, hdrlen, meshhdrlen = 0;
1616 struct ieee80211_hdr hdr;
1617 struct ieee80211s_hdr mesh_hdr;
1618 const u8 *encaps_data;
1619 int encaps_len, skip_header_bytes;
1621 struct sta_info *sta;
1624 if (unlikely(skb->len < ETH_HLEN)) {
1629 nh_pos = skb_network_header(skb) - skb->data;
1630 h_pos = skb_transport_header(skb) - skb->data;
1632 /* convert Ethernet header to proper 802.11 header (based on
1633 * operation mode) */
1634 ethertype = (skb->data[12] << 8) | skb->data[13];
1635 fc = cpu_to_le16(IEEE80211_FTYPE_DATA | IEEE80211_STYPE_DATA);
1637 switch (sdata->vif.type) {
1638 case NL80211_IFTYPE_AP:
1639 case NL80211_IFTYPE_AP_VLAN:
1640 fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS);
1642 memcpy(hdr.addr1, skb->data, ETH_ALEN);
1643 memcpy(hdr.addr2, dev->dev_addr, ETH_ALEN);
1644 memcpy(hdr.addr3, skb->data + ETH_ALEN, ETH_ALEN);
1647 case NL80211_IFTYPE_WDS:
1648 fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS);
1650 memcpy(hdr.addr1, sdata->u.wds.remote_addr, ETH_ALEN);
1651 memcpy(hdr.addr2, dev->dev_addr, ETH_ALEN);
1652 memcpy(hdr.addr3, skb->data, ETH_ALEN);
1653 memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN);
1656 #ifdef CONFIG_MAC80211_MESH
1657 case NL80211_IFTYPE_MESH_POINT:
1658 fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS);
1659 if (!sdata->u.mesh.mshcfg.dot11MeshTTL) {
1660 /* Do not send frames with mesh_ttl == 0 */
1661 sdata->u.mesh.mshstats.dropped_frames_ttl++;
1665 memset(&mesh_hdr, 0, sizeof(mesh_hdr));
1667 if (compare_ether_addr(dev->dev_addr,
1668 skb->data + ETH_ALEN) == 0) {
1670 memset(hdr.addr1, 0, ETH_ALEN);
1671 memcpy(hdr.addr2, dev->dev_addr, ETH_ALEN);
1672 memcpy(hdr.addr3, skb->data, ETH_ALEN);
1673 memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN);
1674 meshhdrlen = ieee80211_new_mesh_header(&mesh_hdr, sdata);
1676 /* packet from other interface */
1677 struct mesh_path *mppath;
1679 memset(hdr.addr1, 0, ETH_ALEN);
1680 memcpy(hdr.addr2, dev->dev_addr, ETH_ALEN);
1681 memcpy(hdr.addr4, dev->dev_addr, ETH_ALEN);
1683 if (is_multicast_ether_addr(skb->data))
1684 memcpy(hdr.addr3, skb->data, ETH_ALEN);
1687 mppath = mpp_path_lookup(skb->data, sdata);
1689 memcpy(hdr.addr3, mppath->mpp, ETH_ALEN);
1691 memset(hdr.addr3, 0xff, ETH_ALEN);
1695 mesh_hdr.flags |= MESH_FLAGS_AE_A5_A6;
1696 mesh_hdr.ttl = sdata->u.mesh.mshcfg.dot11MeshTTL;
1697 put_unaligned(cpu_to_le32(sdata->u.mesh.mesh_seqnum), &mesh_hdr.seqnum);
1698 memcpy(mesh_hdr.eaddr1, skb->data, ETH_ALEN);
1699 memcpy(mesh_hdr.eaddr2, skb->data + ETH_ALEN, ETH_ALEN);
1700 sdata->u.mesh.mesh_seqnum++;
1706 case NL80211_IFTYPE_STATION:
1707 fc |= cpu_to_le16(IEEE80211_FCTL_TODS);
1709 memcpy(hdr.addr1, sdata->u.mgd.bssid, ETH_ALEN);
1710 memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
1711 memcpy(hdr.addr3, skb->data, ETH_ALEN);
1714 case NL80211_IFTYPE_ADHOC:
1716 memcpy(hdr.addr1, skb->data, ETH_ALEN);
1717 memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
1718 memcpy(hdr.addr3, sdata->u.ibss.bssid, ETH_ALEN);
1727 * There's no need to try to look up the destination
1728 * if it is a multicast address (which can only happen
1731 if (!is_multicast_ether_addr(hdr.addr1)) {
1733 sta = sta_info_get(local, hdr.addr1);
1735 sta_flags = get_sta_flags(sta);
1739 /* receiver and we are QoS enabled, use a QoS type frame */
1740 if ((sta_flags & WLAN_STA_WME) && local->hw.queues >= 4) {
1741 fc |= cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
1746 * Drop unicast frames to unauthorised stations unless they are
1747 * EAPOL frames from the local station.
1749 if (!ieee80211_vif_is_mesh(&sdata->vif) &&
1750 unlikely(!is_multicast_ether_addr(hdr.addr1) &&
1751 !(sta_flags & WLAN_STA_AUTHORIZED) &&
1752 !(ethertype == ETH_P_PAE &&
1753 compare_ether_addr(dev->dev_addr,
1754 skb->data + ETH_ALEN) == 0))) {
1755 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
1756 if (net_ratelimit())
1757 printk(KERN_DEBUG "%s: dropped frame to %pM"
1758 " (unauthorized port)\n", dev->name,
1762 I802_DEBUG_INC(local->tx_handlers_drop_unauth_port);
1768 hdr.frame_control = fc;
1769 hdr.duration_id = 0;
1772 skip_header_bytes = ETH_HLEN;
1773 if (ethertype == ETH_P_AARP || ethertype == ETH_P_IPX) {
1774 encaps_data = bridge_tunnel_header;
1775 encaps_len = sizeof(bridge_tunnel_header);
1776 skip_header_bytes -= 2;
1777 } else if (ethertype >= 0x600) {
1778 encaps_data = rfc1042_header;
1779 encaps_len = sizeof(rfc1042_header);
1780 skip_header_bytes -= 2;
1786 skb_pull(skb, skip_header_bytes);
1787 nh_pos -= skip_header_bytes;
1788 h_pos -= skip_header_bytes;
1790 head_need = hdrlen + encaps_len + meshhdrlen - skb_headroom(skb);
1793 * So we need to modify the skb header and hence need a copy of
1794 * that. The head_need variable above doesn't, so far, include
1795 * the needed header space that we don't need right away. If we
1796 * can, then we don't reallocate right now but only after the
1797 * frame arrives at the master device (if it does...)
1799 * If we cannot, however, then we will reallocate to include all
1800 * the ever needed space. Also, if we need to reallocate it anyway,
1801 * make it big enough for everything we may ever need.
1804 if (head_need > 0 || skb_cloned(skb)) {
1805 head_need += IEEE80211_ENCRYPT_HEADROOM;
1806 head_need += local->tx_headroom;
1807 head_need = max_t(int, 0, head_need);
1808 if (ieee80211_skb_resize(local, skb, head_need, true))
1813 memcpy(skb_push(skb, encaps_len), encaps_data, encaps_len);
1814 nh_pos += encaps_len;
1815 h_pos += encaps_len;
1818 if (meshhdrlen > 0) {
1819 memcpy(skb_push(skb, meshhdrlen), &mesh_hdr, meshhdrlen);
1820 nh_pos += meshhdrlen;
1821 h_pos += meshhdrlen;
1824 if (ieee80211_is_data_qos(fc)) {
1825 __le16 *qos_control;
1827 qos_control = (__le16*) skb_push(skb, 2);
1828 memcpy(skb_push(skb, hdrlen - 2), &hdr, hdrlen - 2);
1830 * Maybe we could actually set some fields here, for now just
1831 * initialise to zero to indicate no special operation.
1835 memcpy(skb_push(skb, hdrlen), &hdr, hdrlen);
1840 skb->iif = dev->ifindex;
1842 skb->dev = local->mdev;
1843 dev->stats.tx_packets++;
1844 dev->stats.tx_bytes += skb->len;
1846 /* Update skb pointers to various headers since this modified frame
1847 * is going to go through Linux networking code that may potentially
1848 * need things like pointer to IP header. */
1849 skb_set_mac_header(skb, 0);
1850 skb_set_network_header(skb, nh_pos);
1851 skb_set_transport_header(skb, h_pos);
1853 dev->trans_start = jiffies;
1854 dev_queue_xmit(skb);
1867 * ieee80211_clear_tx_pending may not be called in a context where
1868 * it is possible that it packets could come in again.
1870 void ieee80211_clear_tx_pending(struct ieee80211_local *local)
1874 for (i = 0; i < local->hw.queues; i++)
1875 skb_queue_purge(&local->pending[i]);
1878 static bool ieee80211_tx_pending_skb(struct ieee80211_local *local,
1879 struct sk_buff *skb)
1881 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1882 struct ieee80211_sub_if_data *sdata;
1883 struct sta_info *sta;
1884 struct ieee80211_hdr *hdr;
1885 struct net_device *dev;
1889 /* does interface still exist? */
1890 dev = dev_get_by_index(&init_net, skb->iif);
1896 /* validate info->control.vif against skb->iif */
1897 sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1898 if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
1899 sdata = container_of(sdata->bss,
1900 struct ieee80211_sub_if_data,
1903 if (unlikely(info->control.vif && info->control.vif != &sdata->vif)) {
1909 if (info->flags & IEEE80211_TX_INTFL_NEED_TXPROCESSING) {
1910 ieee80211_tx(dev, skb, true);
1912 hdr = (struct ieee80211_hdr *)skb->data;
1913 sta = sta_info_get(local, hdr->addr1);
1915 ret = __ieee80211_tx(local, &skb, sta);
1916 if (ret != IEEE80211_TX_OK)
1927 * Transmit all pending packets. Called from tasklet, locks master device
1928 * TX lock so that no new packets can come in.
1930 void ieee80211_tx_pending(unsigned long data)
1932 struct ieee80211_local *local = (struct ieee80211_local *)data;
1933 struct net_device *dev = local->mdev;
1934 unsigned long flags;
1939 netif_tx_lock_bh(dev);
1941 for (i = 0; i < local->hw.queues; i++) {
1943 * If queue is stopped by something other than due to pending
1944 * frames, or we have no pending frames, proceed to next queue.
1946 spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
1948 if (local->queue_stop_reasons[i] !=
1949 BIT(IEEE80211_QUEUE_STOP_REASON_PENDING) ||
1950 skb_queue_empty(&local->pending[i]))
1952 spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
1958 * start the queue now to allow processing our packets,
1959 * we're under the tx lock here anyway so nothing will
1960 * happen as a result of this
1962 netif_start_subqueue(local->mdev, i);
1964 while (!skb_queue_empty(&local->pending[i])) {
1965 struct sk_buff *skb = skb_dequeue(&local->pending[i]);
1967 if (!ieee80211_tx_pending_skb(local, skb)) {
1968 skb_queue_head(&local->pending[i], skb);
1973 /* Start regular packet processing again. */
1974 if (skb_queue_empty(&local->pending[i]))
1975 ieee80211_wake_queue_by_reason(&local->hw, i,
1976 IEEE80211_QUEUE_STOP_REASON_PENDING);
1979 netif_tx_unlock_bh(dev);
1983 /* functions for drivers to get certain frames */
1985 static void ieee80211_beacon_add_tim(struct ieee80211_if_ap *bss,
1986 struct sk_buff *skb,
1987 struct beacon_data *beacon)
1991 int i, have_bits = 0, n1, n2;
1993 /* Generate bitmap for TIM only if there are any STAs in power save
1995 if (atomic_read(&bss->num_sta_ps) > 0)
1996 /* in the hope that this is faster than
1997 * checking byte-for-byte */
1998 have_bits = !bitmap_empty((unsigned long*)bss->tim,
1999 IEEE80211_MAX_AID+1);
2001 if (bss->dtim_count == 0)
2002 bss->dtim_count = beacon->dtim_period - 1;
2006 tim = pos = (u8 *) skb_put(skb, 6);
2007 *pos++ = WLAN_EID_TIM;
2009 *pos++ = bss->dtim_count;
2010 *pos++ = beacon->dtim_period;
2012 if (bss->dtim_count == 0 && !skb_queue_empty(&bss->ps_bc_buf))
2016 /* Find largest even number N1 so that bits numbered 1 through
2017 * (N1 x 8) - 1 in the bitmap are 0 and number N2 so that bits
2018 * (N2 + 1) x 8 through 2007 are 0. */
2020 for (i = 0; i < IEEE80211_MAX_TIM_LEN; i++) {
2027 for (i = IEEE80211_MAX_TIM_LEN - 1; i >= n1; i--) {
2034 /* Bitmap control */
2036 /* Part Virt Bitmap */
2037 memcpy(pos, bss->tim + n1, n2 - n1 + 1);
2039 tim[1] = n2 - n1 + 4;
2040 skb_put(skb, n2 - n1);
2042 *pos++ = aid0; /* Bitmap control */
2043 *pos++ = 0; /* Part Virt Bitmap */
2047 struct sk_buff *ieee80211_beacon_get(struct ieee80211_hw *hw,
2048 struct ieee80211_vif *vif)
2050 struct ieee80211_local *local = hw_to_local(hw);
2051 struct sk_buff *skb = NULL;
2052 struct ieee80211_tx_info *info;
2053 struct ieee80211_sub_if_data *sdata = NULL;
2054 struct ieee80211_if_ap *ap = NULL;
2055 struct beacon_data *beacon;
2056 struct ieee80211_supported_band *sband;
2057 enum ieee80211_band band = local->hw.conf.channel->band;
2059 sband = local->hw.wiphy->bands[band];
2063 sdata = vif_to_sdata(vif);
2065 if (sdata->vif.type == NL80211_IFTYPE_AP) {
2067 beacon = rcu_dereference(ap->beacon);
2070 * headroom, head length,
2071 * tail length and maximum TIM length
2073 skb = dev_alloc_skb(local->tx_headroom +
2075 beacon->tail_len + 256);
2079 skb_reserve(skb, local->tx_headroom);
2080 memcpy(skb_put(skb, beacon->head_len), beacon->head,
2084 * Not very nice, but we want to allow the driver to call
2085 * ieee80211_beacon_get() as a response to the set_tim()
2086 * callback. That, however, is already invoked under the
2087 * sta_lock to guarantee consistent and race-free update
2088 * of the tim bitmap in mac80211 and the driver.
2090 if (local->tim_in_locked_section) {
2091 ieee80211_beacon_add_tim(ap, skb, beacon);
2093 unsigned long flags;
2095 spin_lock_irqsave(&local->sta_lock, flags);
2096 ieee80211_beacon_add_tim(ap, skb, beacon);
2097 spin_unlock_irqrestore(&local->sta_lock, flags);
2101 memcpy(skb_put(skb, beacon->tail_len),
2102 beacon->tail, beacon->tail_len);
2105 } else if (sdata->vif.type == NL80211_IFTYPE_ADHOC) {
2106 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
2107 struct ieee80211_hdr *hdr;
2109 if (!ifibss->probe_resp)
2112 skb = skb_copy(ifibss->probe_resp, GFP_ATOMIC);
2116 hdr = (struct ieee80211_hdr *) skb->data;
2117 hdr->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
2118 IEEE80211_STYPE_BEACON);
2120 } else if (ieee80211_vif_is_mesh(&sdata->vif)) {
2121 struct ieee80211_mgmt *mgmt;
2124 /* headroom, head length, tail length and maximum TIM length */
2125 skb = dev_alloc_skb(local->tx_headroom + 400);
2129 skb_reserve(skb, local->hw.extra_tx_headroom);
2130 mgmt = (struct ieee80211_mgmt *)
2131 skb_put(skb, 24 + sizeof(mgmt->u.beacon));
2132 memset(mgmt, 0, 24 + sizeof(mgmt->u.beacon));
2133 mgmt->frame_control =
2134 cpu_to_le16(IEEE80211_FTYPE_MGMT | IEEE80211_STYPE_BEACON);
2135 memset(mgmt->da, 0xff, ETH_ALEN);
2136 memcpy(mgmt->sa, sdata->dev->dev_addr, ETH_ALEN);
2137 /* BSSID is left zeroed, wildcard value */
2138 mgmt->u.beacon.beacon_int =
2139 cpu_to_le16(local->hw.conf.beacon_int);
2140 mgmt->u.beacon.capab_info = 0x0; /* 0x0 for MPs */
2142 pos = skb_put(skb, 2);
2143 *pos++ = WLAN_EID_SSID;
2146 mesh_mgmt_ies_add(skb, sdata);
2152 info = IEEE80211_SKB_CB(skb);
2154 skb->do_not_encrypt = 1;
2158 * XXX: For now, always use the lowest rate
2160 info->control.rates[0].idx = 0;
2161 info->control.rates[0].count = 1;
2162 info->control.rates[1].idx = -1;
2163 info->control.rates[2].idx = -1;
2164 info->control.rates[3].idx = -1;
2165 info->control.rates[4].idx = -1;
2166 BUILD_BUG_ON(IEEE80211_TX_MAX_RATES != 5);
2168 info->control.vif = vif;
2170 info->flags |= IEEE80211_TX_CTL_NO_ACK;
2171 info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT;
2172 info->flags |= IEEE80211_TX_CTL_ASSIGN_SEQ;
2177 EXPORT_SYMBOL(ieee80211_beacon_get);
2179 void ieee80211_rts_get(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
2180 const void *frame, size_t frame_len,
2181 const struct ieee80211_tx_info *frame_txctl,
2182 struct ieee80211_rts *rts)
2184 const struct ieee80211_hdr *hdr = frame;
2186 rts->frame_control =
2187 cpu_to_le16(IEEE80211_FTYPE_CTL | IEEE80211_STYPE_RTS);
2188 rts->duration = ieee80211_rts_duration(hw, vif, frame_len,
2190 memcpy(rts->ra, hdr->addr1, sizeof(rts->ra));
2191 memcpy(rts->ta, hdr->addr2, sizeof(rts->ta));
2193 EXPORT_SYMBOL(ieee80211_rts_get);
2195 void ieee80211_ctstoself_get(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
2196 const void *frame, size_t frame_len,
2197 const struct ieee80211_tx_info *frame_txctl,
2198 struct ieee80211_cts *cts)
2200 const struct ieee80211_hdr *hdr = frame;
2202 cts->frame_control =
2203 cpu_to_le16(IEEE80211_FTYPE_CTL | IEEE80211_STYPE_CTS);
2204 cts->duration = ieee80211_ctstoself_duration(hw, vif,
2205 frame_len, frame_txctl);
2206 memcpy(cts->ra, hdr->addr1, sizeof(cts->ra));
2208 EXPORT_SYMBOL(ieee80211_ctstoself_get);
2211 ieee80211_get_buffered_bc(struct ieee80211_hw *hw,
2212 struct ieee80211_vif *vif)
2214 struct ieee80211_local *local = hw_to_local(hw);
2215 struct sk_buff *skb = NULL;
2216 struct sta_info *sta;
2217 struct ieee80211_tx_data tx;
2218 struct ieee80211_sub_if_data *sdata;
2219 struct ieee80211_if_ap *bss = NULL;
2220 struct beacon_data *beacon;
2221 struct ieee80211_tx_info *info;
2223 sdata = vif_to_sdata(vif);
2230 beacon = rcu_dereference(bss->beacon);
2232 if (sdata->vif.type != NL80211_IFTYPE_AP || !beacon || !beacon->head)
2235 if (bss->dtim_count != 0)
2236 goto out; /* send buffered bc/mc only after DTIM beacon */
2239 skb = skb_dequeue(&bss->ps_bc_buf);
2242 local->total_ps_buffered--;
2244 if (!skb_queue_empty(&bss->ps_bc_buf) && skb->len >= 2) {
2245 struct ieee80211_hdr *hdr =
2246 (struct ieee80211_hdr *) skb->data;
2247 /* more buffered multicast/broadcast frames ==> set
2248 * MoreData flag in IEEE 802.11 header to inform PS
2250 hdr->frame_control |=
2251 cpu_to_le16(IEEE80211_FCTL_MOREDATA);
2254 if (!ieee80211_tx_prepare(local, &tx, skb))
2256 dev_kfree_skb_any(skb);
2259 info = IEEE80211_SKB_CB(skb);
2262 tx.flags |= IEEE80211_TX_PS_BUFFERED;
2263 tx.channel = local->hw.conf.channel;
2264 info->band = tx.channel->band;
2266 if (invoke_tx_handlers(&tx))
2273 EXPORT_SYMBOL(ieee80211_get_buffered_bc);