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 "ieee80211_led.h"
32 #include "ieee80211_rate.h"
34 #define IEEE80211_TX_OK 0
35 #define IEEE80211_TX_AGAIN 1
36 #define IEEE80211_TX_FRAG_AGAIN 2
40 static inline void ieee80211_include_sequence(struct ieee80211_sub_if_data *sdata,
41 struct ieee80211_hdr *hdr)
43 /* Set the sequence number for this frame. */
44 hdr->seq_ctrl = cpu_to_le16(sdata->sequence);
46 /* Increase the sequence number. */
47 sdata->sequence = (sdata->sequence + 0x10) & IEEE80211_SCTL_SEQ;
50 #ifdef CONFIG_MAC80211_LOWTX_FRAME_DUMP
51 static void ieee80211_dump_frame(const char *ifname, const char *title,
52 const struct sk_buff *skb)
54 const struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
58 printk(KERN_DEBUG "%s: %s (len=%d)", ifname, title, skb->len);
64 fc = le16_to_cpu(hdr->frame_control);
65 hdrlen = ieee80211_get_hdrlen(fc);
66 if (hdrlen > skb->len)
69 printk(" FC=0x%04x DUR=0x%04x",
70 fc, le16_to_cpu(hdr->duration_id));
72 printk(" A1=" MAC_FMT, MAC_ARG(hdr->addr1));
74 printk(" A2=" MAC_FMT, MAC_ARG(hdr->addr2));
76 printk(" A3=" MAC_FMT, MAC_ARG(hdr->addr3));
78 printk(" A4=" MAC_FMT, MAC_ARG(hdr->addr4));
81 #else /* CONFIG_MAC80211_LOWTX_FRAME_DUMP */
82 static inline void ieee80211_dump_frame(const char *ifname, const char *title,
86 #endif /* CONFIG_MAC80211_LOWTX_FRAME_DUMP */
88 static u16 ieee80211_duration(struct ieee80211_txrx_data *tx, int group_addr,
91 int rate, mrate, erp, dur, i;
92 struct ieee80211_rate *txrate = tx->u.tx.rate;
93 struct ieee80211_local *local = tx->local;
94 struct ieee80211_hw_mode *mode = tx->u.tx.mode;
96 erp = txrate->flags & IEEE80211_RATE_ERP;
99 * data and mgmt (except PS Poll):
100 * - during CFP: 32768
101 * - during contention period:
102 * if addr1 is group address: 0
103 * if more fragments = 0 and addr1 is individual address: time to
104 * transmit one ACK plus SIFS
105 * if more fragments = 1 and addr1 is individual address: time to
106 * transmit next fragment plus 2 x ACK plus 3 x SIFS
109 * - control response frame (CTS or ACK) shall be transmitted using the
110 * same rate as the immediately previous frame in the frame exchange
111 * sequence, if this rate belongs to the PHY mandatory rates, or else
112 * at the highest possible rate belonging to the PHY rates in the
116 if ((tx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_CTL) {
117 /* TODO: These control frames are not currently sent by
118 * 80211.o, but should they be implemented, this function
119 * needs to be updated to support duration field calculation.
121 * RTS: time needed to transmit pending data/mgmt frame plus
122 * one CTS frame plus one ACK frame plus 3 x SIFS
123 * CTS: duration of immediately previous RTS minus time
124 * required to transmit CTS and its SIFS
125 * ACK: 0 if immediately previous directed data/mgmt had
126 * more=0, with more=1 duration in ACK frame is duration
127 * from previous frame minus time needed to transmit ACK
129 * PS Poll: BIT(15) | BIT(14) | aid
135 if (0 /* FIX: data/mgmt during CFP */)
138 if (group_addr) /* Group address as the destination - no ACK */
141 /* Individual destination address:
142 * IEEE 802.11, Ch. 9.6 (after IEEE 802.11g changes)
143 * CTS and ACK frames shall be transmitted using the highest rate in
144 * basic rate set that is less than or equal to the rate of the
145 * immediately previous frame and that is using the same modulation
146 * (CCK or OFDM). If no basic rate set matches with these requirements,
147 * the highest mandatory rate of the PHY that is less than or equal to
148 * the rate of the previous frame is used.
149 * Mandatory rates for IEEE 802.11g PHY: 1, 2, 5.5, 11, 6, 12, 24 Mbps
152 mrate = 10; /* use 1 Mbps if everything fails */
153 for (i = 0; i < mode->num_rates; i++) {
154 struct ieee80211_rate *r = &mode->rates[i];
155 if (r->rate > txrate->rate)
158 if (IEEE80211_RATE_MODULATION(txrate->flags) !=
159 IEEE80211_RATE_MODULATION(r->flags))
162 if (r->flags & IEEE80211_RATE_BASIC)
164 else if (r->flags & IEEE80211_RATE_MANDATORY)
168 /* No matching basic rate found; use highest suitable mandatory
173 /* Time needed to transmit ACK
174 * (10 bytes + 4-byte FCS = 112 bits) plus SIFS; rounded up
175 * to closest integer */
177 dur = ieee80211_frame_duration(local, 10, rate, erp,
178 tx->sdata->flags & IEEE80211_SDATA_SHORT_PREAMBLE);
181 /* Frame is fragmented: duration increases with time needed to
182 * transmit next fragment plus ACK and 2 x SIFS. */
183 dur *= 2; /* ACK + SIFS */
185 dur += ieee80211_frame_duration(local, next_frag_len,
188 IEEE80211_SDATA_SHORT_PREAMBLE);
194 static inline int __ieee80211_queue_stopped(const struct ieee80211_local *local,
197 return test_bit(IEEE80211_LINK_STATE_XOFF, &local->state[queue]);
200 static inline int __ieee80211_queue_pending(const struct ieee80211_local *local,
203 return test_bit(IEEE80211_LINK_STATE_PENDING, &local->state[queue]);
206 static int inline is_ieee80211_device(struct net_device *dev,
207 struct net_device *master)
209 return (wdev_priv(dev->ieee80211_ptr) ==
210 wdev_priv(master->ieee80211_ptr));
215 static ieee80211_txrx_result
216 ieee80211_tx_h_check_assoc(struct ieee80211_txrx_data *tx)
218 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
219 struct sk_buff *skb = tx->skb;
220 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
221 #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */
224 if (unlikely(tx->local->sta_scanning != 0) &&
225 ((tx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_MGMT ||
226 (tx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_PROBE_REQ))
229 if (tx->flags & IEEE80211_TXRXD_TXPS_BUFFERED)
230 return TXRX_CONTINUE;
232 sta_flags = tx->sta ? tx->sta->flags : 0;
234 if (likely(tx->flags & IEEE80211_TXRXD_TXUNICAST)) {
235 if (unlikely(!(sta_flags & WLAN_STA_ASSOC) &&
236 tx->sdata->type != IEEE80211_IF_TYPE_IBSS &&
237 (tx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA)) {
238 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
239 printk(KERN_DEBUG "%s: dropped data frame to not "
240 "associated station " MAC_FMT "\n",
241 tx->dev->name, MAC_ARG(hdr->addr1));
242 #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */
243 I802_DEBUG_INC(tx->local->tx_handlers_drop_not_assoc);
247 if (unlikely((tx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA &&
248 tx->local->num_sta == 0 &&
249 tx->sdata->type != IEEE80211_IF_TYPE_IBSS)) {
251 * No associated STAs - no need to send multicast
256 return TXRX_CONTINUE;
259 if (unlikely(!tx->u.tx.mgmt_interface && tx->sdata->ieee802_1x &&
260 !(sta_flags & WLAN_STA_AUTHORIZED))) {
261 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
262 printk(KERN_DEBUG "%s: dropped frame to " MAC_FMT
263 " (unauthorized port)\n", tx->dev->name,
264 MAC_ARG(hdr->addr1));
266 I802_DEBUG_INC(tx->local->tx_handlers_drop_unauth_port);
270 return TXRX_CONTINUE;
273 static ieee80211_txrx_result
274 ieee80211_tx_h_sequence(struct ieee80211_txrx_data *tx)
276 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
278 if (ieee80211_get_hdrlen(le16_to_cpu(hdr->frame_control)) >= 24)
279 ieee80211_include_sequence(tx->sdata, hdr);
281 return TXRX_CONTINUE;
284 /* This function is called whenever the AP is about to exceed the maximum limit
285 * of buffered frames for power saving STAs. This situation should not really
286 * happen often during normal operation, so dropping the oldest buffered packet
287 * from each queue should be OK to make some room for new frames. */
288 static void purge_old_ps_buffers(struct ieee80211_local *local)
290 int total = 0, purged = 0;
292 struct ieee80211_sub_if_data *sdata;
293 struct sta_info *sta;
295 read_lock(&local->sub_if_lock);
296 list_for_each_entry(sdata, &local->sub_if_list, list) {
297 struct ieee80211_if_ap *ap;
298 if (sdata->dev == local->mdev ||
299 sdata->type != IEEE80211_IF_TYPE_AP)
302 skb = skb_dequeue(&ap->ps_bc_buf);
307 total += skb_queue_len(&ap->ps_bc_buf);
309 read_unlock(&local->sub_if_lock);
311 read_lock_bh(&local->sta_lock);
312 list_for_each_entry(sta, &local->sta_list, list) {
313 skb = skb_dequeue(&sta->ps_tx_buf);
318 total += skb_queue_len(&sta->ps_tx_buf);
320 read_unlock_bh(&local->sta_lock);
322 local->total_ps_buffered = total;
323 printk(KERN_DEBUG "%s: PS buffers full - purged %d frames\n",
324 local->mdev->name, purged);
327 static inline ieee80211_txrx_result
328 ieee80211_tx_h_multicast_ps_buf(struct ieee80211_txrx_data *tx)
330 /* broadcast/multicast frame */
331 /* If any of the associated stations is in power save mode,
332 * the frame is buffered to be sent after DTIM beacon frame */
333 if ((tx->local->hw.flags & IEEE80211_HW_HOST_BROADCAST_PS_BUFFERING) &&
334 tx->sdata->type != IEEE80211_IF_TYPE_WDS &&
335 tx->sdata->bss && atomic_read(&tx->sdata->bss->num_sta_ps) &&
336 !(tx->fc & IEEE80211_FCTL_ORDER)) {
337 if (tx->local->total_ps_buffered >= TOTAL_MAX_TX_BUFFER)
338 purge_old_ps_buffers(tx->local);
339 if (skb_queue_len(&tx->sdata->bss->ps_bc_buf) >=
341 if (net_ratelimit()) {
342 printk(KERN_DEBUG "%s: BC TX buffer full - "
343 "dropping the oldest frame\n",
346 dev_kfree_skb(skb_dequeue(&tx->sdata->bss->ps_bc_buf));
348 tx->local->total_ps_buffered++;
349 skb_queue_tail(&tx->sdata->bss->ps_bc_buf, tx->skb);
353 return TXRX_CONTINUE;
356 static inline ieee80211_txrx_result
357 ieee80211_tx_h_unicast_ps_buf(struct ieee80211_txrx_data *tx)
359 struct sta_info *sta = tx->sta;
362 ((tx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_MGMT &&
363 (tx->fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_PROBE_RESP)))
364 return TXRX_CONTINUE;
366 if (unlikely((sta->flags & WLAN_STA_PS) && !sta->pspoll)) {
367 struct ieee80211_tx_packet_data *pkt_data;
368 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
369 printk(KERN_DEBUG "STA " MAC_FMT " aid %d: PS buffer (entries "
371 MAC_ARG(sta->addr), sta->aid,
372 skb_queue_len(&sta->ps_tx_buf));
373 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
374 sta->flags |= WLAN_STA_TIM;
375 if (tx->local->total_ps_buffered >= TOTAL_MAX_TX_BUFFER)
376 purge_old_ps_buffers(tx->local);
377 if (skb_queue_len(&sta->ps_tx_buf) >= STA_MAX_TX_BUFFER) {
378 struct sk_buff *old = skb_dequeue(&sta->ps_tx_buf);
379 if (net_ratelimit()) {
380 printk(KERN_DEBUG "%s: STA " MAC_FMT " TX "
381 "buffer full - dropping oldest frame\n",
382 tx->dev->name, MAC_ARG(sta->addr));
386 tx->local->total_ps_buffered++;
387 /* Queue frame to be sent after STA sends an PS Poll frame */
388 if (skb_queue_empty(&sta->ps_tx_buf)) {
389 if (tx->local->ops->set_tim)
390 tx->local->ops->set_tim(local_to_hw(tx->local),
393 bss_tim_set(tx->local, tx->sdata->bss, sta->aid);
395 pkt_data = (struct ieee80211_tx_packet_data *)tx->skb->cb;
396 pkt_data->jiffies = jiffies;
397 skb_queue_tail(&sta->ps_tx_buf, tx->skb);
400 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
401 else if (unlikely(sta->flags & WLAN_STA_PS)) {
402 printk(KERN_DEBUG "%s: STA " MAC_FMT " in PS mode, but pspoll "
403 "set -> send frame\n", tx->dev->name,
406 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
409 return TXRX_CONTINUE;
413 static ieee80211_txrx_result
414 ieee80211_tx_h_ps_buf(struct ieee80211_txrx_data *tx)
416 if (unlikely(tx->flags & IEEE80211_TXRXD_TXPS_BUFFERED))
417 return TXRX_CONTINUE;
419 if (tx->flags & IEEE80211_TXRXD_TXUNICAST)
420 return ieee80211_tx_h_unicast_ps_buf(tx);
422 return ieee80211_tx_h_multicast_ps_buf(tx);
428 static ieee80211_txrx_result
429 ieee80211_tx_h_select_key(struct ieee80211_txrx_data *tx)
431 struct ieee80211_key *key;
433 if (unlikely(tx->u.tx.control->flags & IEEE80211_TXCTL_DO_NOT_ENCRYPT))
435 else if (tx->sta && (key = rcu_dereference(tx->sta->key)))
437 else if ((key = rcu_dereference(tx->sdata->default_key)))
439 else if (tx->sdata->drop_unencrypted &&
440 !(tx->sdata->eapol && ieee80211_is_eapol(tx->skb))) {
441 I802_DEBUG_INC(tx->local->tx_handlers_drop_unencrypted);
445 tx->u.tx.control->flags |= IEEE80211_TXCTL_DO_NOT_ENCRYPT;
449 tx->key->tx_rx_count++;
450 if (unlikely(tx->local->key_tx_rx_threshold &&
451 tx->key->tx_rx_count >
452 tx->local->key_tx_rx_threshold)) {
453 ieee80211_key_threshold_notify(tx->dev, tx->key,
458 return TXRX_CONTINUE;
461 static ieee80211_txrx_result
462 ieee80211_tx_h_fragment(struct ieee80211_txrx_data *tx)
464 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) tx->skb->data;
465 size_t hdrlen, per_fragm, num_fragm, payload_len, left;
466 struct sk_buff **frags, *first, *frag;
470 int frag_threshold = tx->local->fragmentation_threshold;
472 if (!(tx->flags & IEEE80211_TXRXD_FRAGMENTED))
473 return TXRX_CONTINUE;
477 hdrlen = ieee80211_get_hdrlen(tx->fc);
478 payload_len = first->len - hdrlen;
479 per_fragm = frag_threshold - hdrlen - FCS_LEN;
480 num_fragm = DIV_ROUND_UP(payload_len, per_fragm);
482 frags = kzalloc(num_fragm * sizeof(struct sk_buff *), GFP_ATOMIC);
486 hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREFRAGS);
487 seq = le16_to_cpu(hdr->seq_ctrl) & IEEE80211_SCTL_SEQ;
488 pos = first->data + hdrlen + per_fragm;
489 left = payload_len - per_fragm;
490 for (i = 0; i < num_fragm - 1; i++) {
491 struct ieee80211_hdr *fhdr;
497 /* reserve enough extra head and tail room for possible
500 dev_alloc_skb(tx->local->tx_headroom +
502 IEEE80211_ENCRYPT_HEADROOM +
503 IEEE80211_ENCRYPT_TAILROOM);
506 /* Make sure that all fragments use the same priority so
507 * that they end up using the same TX queue */
508 frag->priority = first->priority;
509 skb_reserve(frag, tx->local->tx_headroom +
510 IEEE80211_ENCRYPT_HEADROOM);
511 fhdr = (struct ieee80211_hdr *) skb_put(frag, hdrlen);
512 memcpy(fhdr, first->data, hdrlen);
513 if (i == num_fragm - 2)
514 fhdr->frame_control &= cpu_to_le16(~IEEE80211_FCTL_MOREFRAGS);
515 fhdr->seq_ctrl = cpu_to_le16(seq | ((i + 1) & IEEE80211_SCTL_FRAG));
516 copylen = left > per_fragm ? per_fragm : left;
517 memcpy(skb_put(frag, copylen), pos, copylen);
522 skb_trim(first, hdrlen + per_fragm);
524 tx->u.tx.num_extra_frag = num_fragm - 1;
525 tx->u.tx.extra_frag = frags;
527 return TXRX_CONTINUE;
530 printk(KERN_DEBUG "%s: failed to fragment frame\n", tx->dev->name);
532 for (i = 0; i < num_fragm - 1; i++)
534 dev_kfree_skb(frags[i]);
537 I802_DEBUG_INC(tx->local->tx_handlers_drop_fragment);
541 static int wep_encrypt_skb(struct ieee80211_txrx_data *tx, struct sk_buff *skb)
543 if (!(tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE)) {
544 if (ieee80211_wep_encrypt(tx->local, skb, tx->key))
547 tx->u.tx.control->key_idx = tx->key->conf.hw_key_idx;
548 if (tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV) {
549 if (!ieee80211_wep_add_iv(tx->local, skb, tx->key))
556 static ieee80211_txrx_result
557 ieee80211_tx_h_wep_encrypt(struct ieee80211_txrx_data *tx)
559 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) tx->skb->data;
562 fc = le16_to_cpu(hdr->frame_control);
564 if (!tx->key || tx->key->conf.alg != ALG_WEP ||
565 ((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA &&
566 ((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_MGMT ||
567 (fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_AUTH)))
568 return TXRX_CONTINUE;
570 tx->u.tx.control->iv_len = WEP_IV_LEN;
571 tx->u.tx.control->icv_len = WEP_ICV_LEN;
572 ieee80211_tx_set_iswep(tx);
574 if (wep_encrypt_skb(tx, tx->skb) < 0) {
575 I802_DEBUG_INC(tx->local->tx_handlers_drop_wep);
579 if (tx->u.tx.extra_frag) {
581 for (i = 0; i < tx->u.tx.num_extra_frag; i++) {
582 if (wep_encrypt_skb(tx, tx->u.tx.extra_frag[i]) < 0) {
583 I802_DEBUG_INC(tx->local->
584 tx_handlers_drop_wep);
590 return TXRX_CONTINUE;
593 static ieee80211_txrx_result
594 ieee80211_tx_h_rate_ctrl(struct ieee80211_txrx_data *tx)
596 struct rate_control_extra extra;
598 memset(&extra, 0, sizeof(extra));
599 extra.mode = tx->u.tx.mode;
600 extra.mgmt_data = tx->sdata &&
601 tx->sdata->type == IEEE80211_IF_TYPE_MGMT;
602 extra.ethertype = tx->ethertype;
604 tx->u.tx.rate = rate_control_get_rate(tx->local, tx->dev, tx->skb,
606 if (unlikely(extra.probe != NULL)) {
607 tx->u.tx.control->flags |= IEEE80211_TXCTL_RATE_CTRL_PROBE;
608 tx->flags |= IEEE80211_TXRXD_TXPROBE_LAST_FRAG;
609 tx->u.tx.control->alt_retry_rate = tx->u.tx.rate->val;
610 tx->u.tx.rate = extra.probe;
612 tx->u.tx.control->alt_retry_rate = -1;
616 if (tx->u.tx.mode->mode == MODE_IEEE80211G &&
617 (tx->sdata->flags & IEEE80211_SDATA_USE_PROTECTION) &&
618 (tx->flags & IEEE80211_TXRXD_FRAGMENTED) && extra.nonerp) {
619 tx->u.tx.last_frag_rate = tx->u.tx.rate;
621 tx->flags &= ~IEEE80211_TXRXD_TXPROBE_LAST_FRAG;
623 tx->flags |= IEEE80211_TXRXD_TXPROBE_LAST_FRAG;
624 tx->u.tx.rate = extra.nonerp;
625 tx->u.tx.control->rate = extra.nonerp;
626 tx->u.tx.control->flags &= ~IEEE80211_TXCTL_RATE_CTRL_PROBE;
628 tx->u.tx.last_frag_rate = tx->u.tx.rate;
629 tx->u.tx.control->rate = tx->u.tx.rate;
631 tx->u.tx.control->tx_rate = tx->u.tx.rate->val;
633 return TXRX_CONTINUE;
636 static ieee80211_txrx_result
637 ieee80211_tx_h_misc(struct ieee80211_txrx_data *tx)
639 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) tx->skb->data;
640 u16 fc = le16_to_cpu(hdr->frame_control);
642 struct ieee80211_tx_control *control = tx->u.tx.control;
643 struct ieee80211_hw_mode *mode = tx->u.tx.mode;
645 if (!is_multicast_ether_addr(hdr->addr1)) {
646 if (tx->skb->len + FCS_LEN > tx->local->rts_threshold &&
647 tx->local->rts_threshold < IEEE80211_MAX_RTS_THRESHOLD) {
648 control->flags |= IEEE80211_TXCTL_USE_RTS_CTS;
649 control->flags |= IEEE80211_TXCTL_LONG_RETRY_LIMIT;
650 control->retry_limit =
651 tx->local->long_retry_limit;
653 control->retry_limit =
654 tx->local->short_retry_limit;
657 control->retry_limit = 1;
660 if (tx->flags & IEEE80211_TXRXD_FRAGMENTED) {
661 /* Do not use multiple retry rates when sending fragmented
663 * TODO: The last fragment could still use multiple retry
665 control->alt_retry_rate = -1;
668 /* Use CTS protection for unicast frames sent using extended rates if
669 * there are associated non-ERP stations and RTS/CTS is not configured
671 if (mode->mode == MODE_IEEE80211G &&
672 (tx->u.tx.rate->flags & IEEE80211_RATE_ERP) &&
673 (tx->flags & IEEE80211_TXRXD_TXUNICAST) &&
674 (tx->sdata->flags & IEEE80211_SDATA_USE_PROTECTION) &&
675 !(control->flags & IEEE80211_TXCTL_USE_RTS_CTS))
676 control->flags |= IEEE80211_TXCTL_USE_CTS_PROTECT;
678 /* Transmit data frames using short preambles if the driver supports
679 * short preambles at the selected rate and short preambles are
680 * available on the network at the current point in time. */
681 if (((fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA) &&
682 (tx->u.tx.rate->flags & IEEE80211_RATE_PREAMBLE2) &&
683 (tx->sdata->flags & IEEE80211_SDATA_SHORT_PREAMBLE) &&
684 (!tx->sta || (tx->sta->flags & WLAN_STA_SHORT_PREAMBLE))) {
685 tx->u.tx.control->tx_rate = tx->u.tx.rate->val2;
688 /* Setup duration field for the first fragment of the frame. Duration
689 * for remaining fragments will be updated when they are being sent
690 * to low-level driver in ieee80211_tx(). */
691 dur = ieee80211_duration(tx, is_multicast_ether_addr(hdr->addr1),
692 (tx->flags & IEEE80211_TXRXD_FRAGMENTED) ?
693 tx->u.tx.extra_frag[0]->len : 0);
694 hdr->duration_id = cpu_to_le16(dur);
696 if ((control->flags & IEEE80211_TXCTL_USE_RTS_CTS) ||
697 (control->flags & IEEE80211_TXCTL_USE_CTS_PROTECT)) {
698 struct ieee80211_rate *rate;
700 /* Do not use multiple retry rates when using RTS/CTS */
701 control->alt_retry_rate = -1;
703 /* Use min(data rate, max base rate) as CTS/RTS rate */
704 rate = tx->u.tx.rate;
705 while (rate > mode->rates &&
706 !(rate->flags & IEEE80211_RATE_BASIC))
709 control->rts_cts_rate = rate->val;
710 control->rts_rate = rate;
714 tx->sta->tx_packets++;
715 tx->sta->tx_fragments++;
716 tx->sta->tx_bytes += tx->skb->len;
717 if (tx->u.tx.extra_frag) {
719 tx->sta->tx_fragments += tx->u.tx.num_extra_frag;
720 for (i = 0; i < tx->u.tx.num_extra_frag; i++) {
722 tx->u.tx.extra_frag[i]->len;
728 * Tell hardware to not encrypt when we had sw crypto.
729 * Because we use the same flag to internally indicate that
730 * no (software) encryption should be done, we have to set it
731 * after all crypto handlers.
733 if (tx->key && !(tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))
734 tx->u.tx.control->flags |= IEEE80211_TXCTL_DO_NOT_ENCRYPT;
736 return TXRX_CONTINUE;
739 static ieee80211_txrx_result
740 ieee80211_tx_h_load_stats(struct ieee80211_txrx_data *tx)
742 struct ieee80211_local *local = tx->local;
743 struct ieee80211_hw_mode *mode = tx->u.tx.mode;
744 struct sk_buff *skb = tx->skb;
745 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
746 u32 load = 0, hdrtime;
748 /* TODO: this could be part of tx_status handling, so that the number
749 * of retries would be known; TX rate should in that case be stored
750 * somewhere with the packet */
752 /* Estimate total channel use caused by this frame */
754 /* 1 bit at 1 Mbit/s takes 1 usec; in channel_use values,
755 * 1 usec = 1/8 * (1080 / 10) = 13.5 */
757 if (mode->mode == MODE_IEEE80211A ||
758 (mode->mode == MODE_IEEE80211G &&
759 tx->u.tx.rate->flags & IEEE80211_RATE_ERP))
760 hdrtime = CHAN_UTIL_HDR_SHORT;
762 hdrtime = CHAN_UTIL_HDR_LONG;
765 if (!is_multicast_ether_addr(hdr->addr1))
768 if (tx->u.tx.control->flags & IEEE80211_TXCTL_USE_RTS_CTS)
770 else if (tx->u.tx.control->flags & IEEE80211_TXCTL_USE_CTS_PROTECT)
773 load += skb->len * tx->u.tx.rate->rate_inv;
775 if (tx->u.tx.extra_frag) {
777 for (i = 0; i < tx->u.tx.num_extra_frag; i++) {
779 load += tx->u.tx.extra_frag[i]->len *
784 /* Divide channel_use by 8 to avoid wrapping around the counter */
785 load >>= CHAN_UTIL_SHIFT;
786 local->channel_use_raw += load;
788 tx->sta->channel_use_raw += load;
789 tx->sdata->channel_use_raw += load;
791 return TXRX_CONTINUE;
794 /* TODO: implement register/unregister functions for adding TX/RX handlers
795 * into ordered list */
797 ieee80211_tx_handler ieee80211_tx_handlers[] =
799 ieee80211_tx_h_check_assoc,
800 ieee80211_tx_h_sequence,
801 ieee80211_tx_h_ps_buf,
802 ieee80211_tx_h_select_key,
803 ieee80211_tx_h_michael_mic_add,
804 ieee80211_tx_h_fragment,
805 ieee80211_tx_h_tkip_encrypt,
806 ieee80211_tx_h_ccmp_encrypt,
807 ieee80211_tx_h_wep_encrypt,
808 ieee80211_tx_h_rate_ctrl,
810 ieee80211_tx_h_load_stats,
814 /* actual transmit path */
817 * deal with packet injection down monitor interface
818 * with Radiotap Header -- only called for monitor mode interface
820 static ieee80211_txrx_result
821 __ieee80211_parse_tx_radiotap(
822 struct ieee80211_txrx_data *tx,
823 struct sk_buff *skb, struct ieee80211_tx_control *control)
826 * this is the moment to interpret and discard the radiotap header that
827 * must be at the start of the packet injected in Monitor mode
829 * Need to take some care with endian-ness since radiotap
830 * args are little-endian
833 struct ieee80211_radiotap_iterator iterator;
834 struct ieee80211_radiotap_header *rthdr =
835 (struct ieee80211_radiotap_header *) skb->data;
836 struct ieee80211_hw_mode *mode = tx->local->hw.conf.mode;
837 int ret = ieee80211_radiotap_iterator_init(&iterator, rthdr, skb->len);
840 * default control situation for all injected packets
841 * FIXME: this does not suit all usage cases, expand to allow control
844 control->retry_limit = 1; /* no retry */
845 control->flags &= ~(IEEE80211_TXCTL_USE_RTS_CTS |
846 IEEE80211_TXCTL_USE_CTS_PROTECT);
847 control->flags |= IEEE80211_TXCTL_DO_NOT_ENCRYPT |
848 IEEE80211_TXCTL_NO_ACK;
849 control->antenna_sel_tx = 0; /* default to default antenna */
852 * for every radiotap entry that is present
853 * (ieee80211_radiotap_iterator_next returns -ENOENT when no more
854 * entries present, or -EINVAL on error)
860 ret = ieee80211_radiotap_iterator_next(&iterator);
865 /* see if this argument is something we can use */
866 switch (iterator.this_arg_index) {
868 * You must take care when dereferencing iterator.this_arg
869 * for multibyte types... the pointer is not aligned. Use
870 * get_unaligned((type *)iterator.this_arg) to dereference
871 * iterator.this_arg for type "type" safely on all arches.
873 case IEEE80211_RADIOTAP_RATE:
875 * radiotap rate u8 is in 500kbps units eg, 0x02=1Mbps
876 * ieee80211 rate int is in 100kbps units eg, 0x0a=1Mbps
878 target_rate = (*iterator.this_arg) * 5;
879 for (i = 0; i < mode->num_rates; i++) {
880 struct ieee80211_rate *r = &mode->rates[i];
882 if (r->rate > target_rate)
887 if (r->flags & IEEE80211_RATE_PREAMBLE2)
888 control->tx_rate = r->val2;
890 control->tx_rate = r->val;
892 /* end on exact match */
893 if (r->rate == target_rate)
898 case IEEE80211_RADIOTAP_ANTENNA:
900 * radiotap uses 0 for 1st ant, mac80211 is 1 for
903 control->antenna_sel_tx = (*iterator.this_arg) + 1;
906 case IEEE80211_RADIOTAP_DBM_TX_POWER:
907 control->power_level = *iterator.this_arg;
910 case IEEE80211_RADIOTAP_FLAGS:
911 if (*iterator.this_arg & IEEE80211_RADIOTAP_F_FCS) {
913 * this indicates that the skb we have been
914 * handed has the 32-bit FCS CRC at the end...
915 * we should react to that by snipping it off
916 * because it will be recomputed and added
919 if (skb->len < (iterator.max_length + FCS_LEN))
922 skb_trim(skb, skb->len - FCS_LEN);
931 if (ret != -ENOENT) /* ie, if we didn't simply run out of fields */
935 * remove the radiotap header
936 * iterator->max_length was sanity-checked against
937 * skb->len by iterator init
939 skb_pull(skb, iterator.max_length);
941 return TXRX_CONTINUE;
944 static ieee80211_txrx_result inline
945 __ieee80211_tx_prepare(struct ieee80211_txrx_data *tx,
947 struct net_device *dev,
948 struct ieee80211_tx_control *control)
950 struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
951 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
952 struct ieee80211_sub_if_data *sdata;
953 ieee80211_txrx_result res = TXRX_CONTINUE;
957 memset(tx, 0, sizeof(*tx));
959 tx->dev = dev; /* use original interface */
961 tx->sdata = IEEE80211_DEV_TO_SUB_IF(dev);
962 tx->sta = sta_info_get(local, hdr->addr1);
963 tx->fc = le16_to_cpu(hdr->frame_control);
966 * set defaults for things that can be set by
967 * injected radiotap headers
969 control->power_level = local->hw.conf.power_level;
970 control->antenna_sel_tx = local->hw.conf.antenna_sel_tx;
972 /* process and remove the injection radiotap header */
973 sdata = IEEE80211_DEV_TO_SUB_IF(dev);
974 if (unlikely(sdata->type == IEEE80211_IF_TYPE_MNTR)) {
975 if (__ieee80211_parse_tx_radiotap(tx, skb, control) ==
980 * we removed the radiotap header after this point,
981 * we filled control with what we could use
982 * set to the actual ieee header now
984 hdr = (struct ieee80211_hdr *) skb->data;
985 res = TXRX_QUEUED; /* indication it was monitor packet */
988 tx->u.tx.control = control;
989 if (is_multicast_ether_addr(hdr->addr1)) {
990 tx->flags &= ~IEEE80211_TXRXD_TXUNICAST;
991 control->flags |= IEEE80211_TXCTL_NO_ACK;
993 tx->flags |= IEEE80211_TXRXD_TXUNICAST;
994 control->flags &= ~IEEE80211_TXCTL_NO_ACK;
996 if (local->fragmentation_threshold < IEEE80211_MAX_FRAG_THRESHOLD &&
997 (tx->flags & IEEE80211_TXRXD_TXUNICAST) &&
998 skb->len + FCS_LEN > local->fragmentation_threshold &&
999 !local->ops->set_frag_threshold)
1000 tx->flags |= IEEE80211_TXRXD_FRAGMENTED;
1002 tx->flags &= ~IEEE80211_TXRXD_FRAGMENTED;
1004 control->flags |= IEEE80211_TXCTL_CLEAR_DST_MASK;
1005 else if (tx->sta->clear_dst_mask) {
1006 control->flags |= IEEE80211_TXCTL_CLEAR_DST_MASK;
1007 tx->sta->clear_dst_mask = 0;
1009 hdrlen = ieee80211_get_hdrlen(tx->fc);
1010 if (skb->len > hdrlen + sizeof(rfc1042_header) + 2) {
1011 u8 *pos = &skb->data[hdrlen + sizeof(rfc1042_header)];
1012 tx->ethertype = (pos[0] << 8) | pos[1];
1014 control->flags |= IEEE80211_TXCTL_FIRST_FRAGMENT;
1019 /* Device in tx->dev has a reference added; use dev_put(tx->dev) when
1020 * finished with it. */
1021 static int inline ieee80211_tx_prepare(struct ieee80211_txrx_data *tx,
1022 struct sk_buff *skb,
1023 struct net_device *mdev,
1024 struct ieee80211_tx_control *control)
1026 struct ieee80211_tx_packet_data *pkt_data;
1027 struct net_device *dev;
1029 pkt_data = (struct ieee80211_tx_packet_data *)skb->cb;
1030 dev = dev_get_by_index(&init_net, pkt_data->ifindex);
1031 if (unlikely(dev && !is_ieee80211_device(dev, mdev))) {
1037 __ieee80211_tx_prepare(tx, skb, dev, control);
1041 static int __ieee80211_tx(struct ieee80211_local *local, struct sk_buff *skb,
1042 struct ieee80211_txrx_data *tx)
1044 struct ieee80211_tx_control *control = tx->u.tx.control;
1047 if (!ieee80211_qdisc_installed(local->mdev) &&
1048 __ieee80211_queue_stopped(local, 0)) {
1049 netif_stop_queue(local->mdev);
1050 return IEEE80211_TX_AGAIN;
1053 ieee80211_dump_frame(local->mdev->name, "TX to low-level driver", skb);
1054 ret = local->ops->tx(local_to_hw(local), skb, control);
1056 return IEEE80211_TX_AGAIN;
1057 local->mdev->trans_start = jiffies;
1058 ieee80211_led_tx(local, 1);
1060 if (tx->u.tx.extra_frag) {
1061 control->flags &= ~(IEEE80211_TXCTL_USE_RTS_CTS |
1062 IEEE80211_TXCTL_USE_CTS_PROTECT |
1063 IEEE80211_TXCTL_CLEAR_DST_MASK |
1064 IEEE80211_TXCTL_FIRST_FRAGMENT);
1065 for (i = 0; i < tx->u.tx.num_extra_frag; i++) {
1066 if (!tx->u.tx.extra_frag[i])
1068 if (__ieee80211_queue_stopped(local, control->queue))
1069 return IEEE80211_TX_FRAG_AGAIN;
1070 if (i == tx->u.tx.num_extra_frag) {
1071 control->tx_rate = tx->u.tx.last_frag_hwrate;
1072 control->rate = tx->u.tx.last_frag_rate;
1073 if (tx->flags & IEEE80211_TXRXD_TXPROBE_LAST_FRAG)
1075 IEEE80211_TXCTL_RATE_CTRL_PROBE;
1078 ~IEEE80211_TXCTL_RATE_CTRL_PROBE;
1081 ieee80211_dump_frame(local->mdev->name,
1082 "TX to low-level driver",
1083 tx->u.tx.extra_frag[i]);
1084 ret = local->ops->tx(local_to_hw(local),
1085 tx->u.tx.extra_frag[i],
1088 return IEEE80211_TX_FRAG_AGAIN;
1089 local->mdev->trans_start = jiffies;
1090 ieee80211_led_tx(local, 1);
1091 tx->u.tx.extra_frag[i] = NULL;
1093 kfree(tx->u.tx.extra_frag);
1094 tx->u.tx.extra_frag = NULL;
1096 return IEEE80211_TX_OK;
1099 static int ieee80211_tx(struct net_device *dev, struct sk_buff *skb,
1100 struct ieee80211_tx_control *control, int mgmt)
1102 struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
1103 struct sta_info *sta;
1104 ieee80211_tx_handler *handler;
1105 struct ieee80211_txrx_data tx;
1106 ieee80211_txrx_result res = TXRX_DROP, res_prepare;
1109 WARN_ON(__ieee80211_queue_pending(local, control->queue));
1111 if (unlikely(skb->len < 10)) {
1116 res_prepare = __ieee80211_tx_prepare(&tx, skb, dev, control);
1118 if (res_prepare == TXRX_DROP) {
1124 * key references are protected using RCU and this requires that
1125 * we are in a read-site RCU section during receive processing
1130 tx.u.tx.mgmt_interface = mgmt;
1131 tx.u.tx.mode = local->hw.conf.mode;
1133 if (res_prepare == TXRX_QUEUED) { /* if it was an injected packet */
1134 res = TXRX_CONTINUE;
1136 for (handler = local->tx_handlers; *handler != NULL;
1138 res = (*handler)(&tx);
1139 if (res != TXRX_CONTINUE)
1144 skb = tx.skb; /* handlers are allowed to change skb */
1149 if (unlikely(res == TXRX_DROP)) {
1150 I802_DEBUG_INC(local->tx_handlers_drop);
1154 if (unlikely(res == TXRX_QUEUED)) {
1155 I802_DEBUG_INC(local->tx_handlers_queued);
1160 if (tx.u.tx.extra_frag) {
1161 for (i = 0; i < tx.u.tx.num_extra_frag; i++) {
1163 struct ieee80211_hdr *hdr =
1164 (struct ieee80211_hdr *)
1165 tx.u.tx.extra_frag[i]->data;
1167 if (i + 1 < tx.u.tx.num_extra_frag) {
1168 next_len = tx.u.tx.extra_frag[i + 1]->len;
1171 tx.u.tx.rate = tx.u.tx.last_frag_rate;
1172 tx.u.tx.last_frag_hwrate = tx.u.tx.rate->val;
1174 dur = ieee80211_duration(&tx, 0, next_len);
1175 hdr->duration_id = cpu_to_le16(dur);
1180 ret = __ieee80211_tx(local, skb, &tx);
1182 struct ieee80211_tx_stored_packet *store =
1183 &local->pending_packet[control->queue];
1185 if (ret == IEEE80211_TX_FRAG_AGAIN)
1187 set_bit(IEEE80211_LINK_STATE_PENDING,
1188 &local->state[control->queue]);
1190 /* When the driver gets out of buffers during sending of
1191 * fragments and calls ieee80211_stop_queue, there is
1192 * a small window between IEEE80211_LINK_STATE_XOFF and
1193 * IEEE80211_LINK_STATE_PENDING flags are set. If a buffer
1194 * gets available in that window (i.e. driver calls
1195 * ieee80211_wake_queue), we would end up with ieee80211_tx
1196 * called with IEEE80211_LINK_STATE_PENDING. Prevent this by
1197 * continuing transmitting here when that situation is
1198 * possible to have happened. */
1199 if (!__ieee80211_queue_stopped(local, control->queue)) {
1200 clear_bit(IEEE80211_LINK_STATE_PENDING,
1201 &local->state[control->queue]);
1204 memcpy(&store->control, control,
1205 sizeof(struct ieee80211_tx_control));
1207 store->extra_frag = tx.u.tx.extra_frag;
1208 store->num_extra_frag = tx.u.tx.num_extra_frag;
1209 store->last_frag_hwrate = tx.u.tx.last_frag_hwrate;
1210 store->last_frag_rate = tx.u.tx.last_frag_rate;
1211 store->last_frag_rate_ctrl_probe =
1212 !!(tx.flags & IEEE80211_TXRXD_TXPROBE_LAST_FRAG);
1220 for (i = 0; i < tx.u.tx.num_extra_frag; i++)
1221 if (tx.u.tx.extra_frag[i])
1222 dev_kfree_skb(tx.u.tx.extra_frag[i]);
1223 kfree(tx.u.tx.extra_frag);
1228 /* device xmit handlers */
1230 int ieee80211_master_start_xmit(struct sk_buff *skb,
1231 struct net_device *dev)
1233 struct ieee80211_tx_control control;
1234 struct ieee80211_tx_packet_data *pkt_data;
1235 struct net_device *odev = NULL;
1236 struct ieee80211_sub_if_data *osdata;
1241 * copy control out of the skb so other people can use skb->cb
1243 pkt_data = (struct ieee80211_tx_packet_data *)skb->cb;
1244 memset(&control, 0, sizeof(struct ieee80211_tx_control));
1246 if (pkt_data->ifindex)
1247 odev = dev_get_by_index(&init_net, pkt_data->ifindex);
1248 if (unlikely(odev && !is_ieee80211_device(odev, dev))) {
1252 if (unlikely(!odev)) {
1253 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
1254 printk(KERN_DEBUG "%s: Discarded packet with nonexistent "
1255 "originating device\n", dev->name);
1260 osdata = IEEE80211_DEV_TO_SUB_IF(odev);
1262 headroom = osdata->local->tx_headroom + IEEE80211_ENCRYPT_HEADROOM;
1263 if (skb_headroom(skb) < headroom) {
1264 if (pskb_expand_head(skb, headroom, 0, GFP_ATOMIC)) {
1271 control.ifindex = odev->ifindex;
1272 control.type = osdata->type;
1273 if (pkt_data->flags & IEEE80211_TXPD_REQ_TX_STATUS)
1274 control.flags |= IEEE80211_TXCTL_REQ_TX_STATUS;
1275 if (pkt_data->flags & IEEE80211_TXPD_DO_NOT_ENCRYPT)
1276 control.flags |= IEEE80211_TXCTL_DO_NOT_ENCRYPT;
1277 if (pkt_data->flags & IEEE80211_TXPD_REQUEUE)
1278 control.flags |= IEEE80211_TXCTL_REQUEUE;
1279 control.queue = pkt_data->queue;
1281 ret = ieee80211_tx(odev, skb, &control,
1282 control.type == IEEE80211_IF_TYPE_MGMT);
1288 int ieee80211_monitor_start_xmit(struct sk_buff *skb,
1289 struct net_device *dev)
1291 struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
1292 struct ieee80211_tx_packet_data *pkt_data;
1293 struct ieee80211_radiotap_header *prthdr =
1294 (struct ieee80211_radiotap_header *)skb->data;
1297 /* check for not even having the fixed radiotap header part */
1298 if (unlikely(skb->len < sizeof(struct ieee80211_radiotap_header)))
1299 goto fail; /* too short to be possibly valid */
1301 /* is it a header version we can trust to find length from? */
1302 if (unlikely(prthdr->it_version))
1303 goto fail; /* only version 0 is supported */
1305 /* then there must be a radiotap header with a length we can use */
1306 len_rthdr = ieee80211_get_radiotap_len(skb->data);
1308 /* does the skb contain enough to deliver on the alleged length? */
1309 if (unlikely(skb->len < len_rthdr))
1310 goto fail; /* skb too short for claimed rt header extent */
1312 skb->dev = local->mdev;
1314 pkt_data = (struct ieee80211_tx_packet_data *)skb->cb;
1315 memset(pkt_data, 0, sizeof(*pkt_data));
1316 /* needed because we set skb device to master */
1317 pkt_data->ifindex = dev->ifindex;
1319 pkt_data->flags |= IEEE80211_TXPD_DO_NOT_ENCRYPT;
1322 * fix up the pointers accounting for the radiotap
1323 * header still being in there. We are being given
1324 * a precooked IEEE80211 header so no need for
1327 skb_set_mac_header(skb, len_rthdr);
1329 * these are just fixed to the end of the rt area since we
1330 * don't have any better information and at this point, nobody cares
1332 skb_set_network_header(skb, len_rthdr);
1333 skb_set_transport_header(skb, len_rthdr);
1335 /* pass the radiotap header up to the next stage intact */
1336 dev_queue_xmit(skb);
1337 return NETDEV_TX_OK;
1341 return NETDEV_TX_OK; /* meaning, we dealt with the skb */
1345 * ieee80211_subif_start_xmit - netif start_xmit function for Ethernet-type
1346 * subinterfaces (wlan#, WDS, and VLAN interfaces)
1347 * @skb: packet to be sent
1348 * @dev: incoming interface
1350 * Returns: 0 on success (and frees skb in this case) or 1 on failure (skb will
1351 * not be freed, and caller is responsible for either retrying later or freeing
1354 * This function takes in an Ethernet header and encapsulates it with suitable
1355 * IEEE 802.11 header based on which interface the packet is coming in. The
1356 * encapsulated packet will then be passed to master interface, wlan#.11, for
1357 * transmission (through low-level driver).
1359 int ieee80211_subif_start_xmit(struct sk_buff *skb,
1360 struct net_device *dev)
1362 struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
1363 struct ieee80211_tx_packet_data *pkt_data;
1364 struct ieee80211_sub_if_data *sdata;
1365 int ret = 1, head_need;
1366 u16 ethertype, hdrlen, fc;
1367 struct ieee80211_hdr hdr;
1368 const u8 *encaps_data;
1369 int encaps_len, skip_header_bytes;
1371 struct sta_info *sta;
1373 sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1374 if (unlikely(skb->len < ETH_HLEN)) {
1375 printk(KERN_DEBUG "%s: short skb (len=%d)\n",
1376 dev->name, skb->len);
1381 nh_pos = skb_network_header(skb) - skb->data;
1382 h_pos = skb_transport_header(skb) - skb->data;
1384 /* convert Ethernet header to proper 802.11 header (based on
1385 * operation mode) */
1386 ethertype = (skb->data[12] << 8) | skb->data[13];
1387 /* TODO: handling for 802.1x authorized/unauthorized port */
1388 fc = IEEE80211_FTYPE_DATA | IEEE80211_STYPE_DATA;
1390 switch (sdata->type) {
1391 case IEEE80211_IF_TYPE_AP:
1392 case IEEE80211_IF_TYPE_VLAN:
1393 fc |= IEEE80211_FCTL_FROMDS;
1395 memcpy(hdr.addr1, skb->data, ETH_ALEN);
1396 memcpy(hdr.addr2, dev->dev_addr, ETH_ALEN);
1397 memcpy(hdr.addr3, skb->data + ETH_ALEN, ETH_ALEN);
1400 case IEEE80211_IF_TYPE_WDS:
1401 fc |= IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS;
1403 memcpy(hdr.addr1, sdata->u.wds.remote_addr, ETH_ALEN);
1404 memcpy(hdr.addr2, dev->dev_addr, ETH_ALEN);
1405 memcpy(hdr.addr3, skb->data, ETH_ALEN);
1406 memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN);
1409 case IEEE80211_IF_TYPE_STA:
1410 fc |= IEEE80211_FCTL_TODS;
1412 memcpy(hdr.addr1, sdata->u.sta.bssid, ETH_ALEN);
1413 memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
1414 memcpy(hdr.addr3, skb->data, ETH_ALEN);
1417 case IEEE80211_IF_TYPE_IBSS:
1419 memcpy(hdr.addr1, skb->data, ETH_ALEN);
1420 memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
1421 memcpy(hdr.addr3, sdata->u.sta.bssid, ETH_ALEN);
1429 /* receiver is QoS enabled, use a QoS type frame */
1430 sta = sta_info_get(local, hdr.addr1);
1432 if (sta->flags & WLAN_STA_WME) {
1433 fc |= IEEE80211_STYPE_QOS_DATA;
1439 hdr.frame_control = cpu_to_le16(fc);
1440 hdr.duration_id = 0;
1443 skip_header_bytes = ETH_HLEN;
1444 if (ethertype == ETH_P_AARP || ethertype == ETH_P_IPX) {
1445 encaps_data = bridge_tunnel_header;
1446 encaps_len = sizeof(bridge_tunnel_header);
1447 skip_header_bytes -= 2;
1448 } else if (ethertype >= 0x600) {
1449 encaps_data = rfc1042_header;
1450 encaps_len = sizeof(rfc1042_header);
1451 skip_header_bytes -= 2;
1457 skb_pull(skb, skip_header_bytes);
1458 nh_pos -= skip_header_bytes;
1459 h_pos -= skip_header_bytes;
1461 /* TODO: implement support for fragments so that there is no need to
1462 * reallocate and copy payload; it might be enough to support one
1463 * extra fragment that would be copied in the beginning of the frame
1464 * data.. anyway, it would be nice to include this into skb structure
1467 * There are few options for this:
1468 * use skb->cb as an extra space for 802.11 header
1469 * allocate new buffer if not enough headroom
1470 * make sure that there is enough headroom in every skb by increasing
1471 * build in headroom in __dev_alloc_skb() (linux/skbuff.h) and
1472 * alloc_skb() (net/core/skbuff.c)
1474 head_need = hdrlen + encaps_len + local->tx_headroom;
1475 head_need -= skb_headroom(skb);
1477 /* We are going to modify skb data, so make a copy of it if happens to
1478 * be cloned. This could happen, e.g., with Linux bridge code passing
1479 * us broadcast frames. */
1481 if (head_need > 0 || skb_cloned(skb)) {
1483 printk(KERN_DEBUG "%s: need to reallocate buffer for %d bytes "
1484 "of headroom\n", dev->name, head_need);
1487 if (skb_cloned(skb))
1488 I802_DEBUG_INC(local->tx_expand_skb_head_cloned);
1490 I802_DEBUG_INC(local->tx_expand_skb_head);
1491 /* Since we have to reallocate the buffer, make sure that there
1492 * is enough room for possible WEP IV/ICV and TKIP (8 bytes
1493 * before payload and 12 after). */
1494 if (pskb_expand_head(skb, (head_need > 0 ? head_need + 8 : 8),
1496 printk(KERN_DEBUG "%s: failed to reallocate TX buffer"
1503 memcpy(skb_push(skb, encaps_len), encaps_data, encaps_len);
1504 nh_pos += encaps_len;
1505 h_pos += encaps_len;
1508 if (fc & IEEE80211_STYPE_QOS_DATA) {
1509 __le16 *qos_control;
1511 qos_control = (__le16*) skb_push(skb, 2);
1512 memcpy(skb_push(skb, hdrlen - 2), &hdr, hdrlen - 2);
1514 * Maybe we could actually set some fields here, for now just
1515 * initialise to zero to indicate no special operation.
1519 memcpy(skb_push(skb, hdrlen), &hdr, hdrlen);
1524 pkt_data = (struct ieee80211_tx_packet_data *)skb->cb;
1525 memset(pkt_data, 0, sizeof(struct ieee80211_tx_packet_data));
1526 pkt_data->ifindex = dev->ifindex;
1527 if (sdata->type == IEEE80211_IF_TYPE_MGMT)
1528 pkt_data->flags |= IEEE80211_TXPD_MGMT_IFACE;
1530 skb->dev = local->mdev;
1531 sdata->stats.tx_packets++;
1532 sdata->stats.tx_bytes += skb->len;
1534 /* Update skb pointers to various headers since this modified frame
1535 * is going to go through Linux networking code that may potentially
1536 * need things like pointer to IP header. */
1537 skb_set_mac_header(skb, 0);
1538 skb_set_network_header(skb, nh_pos);
1539 skb_set_transport_header(skb, h_pos);
1541 dev->trans_start = jiffies;
1542 dev_queue_xmit(skb);
1554 * This is the transmit routine for the 802.11 type interfaces
1555 * called by upper layers of the linux networking
1556 * stack when it has a frame to transmit
1558 int ieee80211_mgmt_start_xmit(struct sk_buff *skb, struct net_device *dev)
1560 struct ieee80211_sub_if_data *sdata;
1561 struct ieee80211_tx_packet_data *pkt_data;
1562 struct ieee80211_hdr *hdr;
1565 sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1567 if (skb->len < 10) {
1572 if (skb_headroom(skb) < sdata->local->tx_headroom) {
1573 if (pskb_expand_head(skb, sdata->local->tx_headroom,
1580 hdr = (struct ieee80211_hdr *) skb->data;
1581 fc = le16_to_cpu(hdr->frame_control);
1583 pkt_data = (struct ieee80211_tx_packet_data *) skb->cb;
1584 memset(pkt_data, 0, sizeof(struct ieee80211_tx_packet_data));
1585 pkt_data->ifindex = sdata->dev->ifindex;
1586 if (sdata->type == IEEE80211_IF_TYPE_MGMT)
1587 pkt_data->flags |= IEEE80211_TXPD_MGMT_IFACE;
1589 skb->priority = 20; /* use hardcoded priority for mgmt TX queue */
1590 skb->dev = sdata->local->mdev;
1593 * We're using the protocol field of the the frame control header
1594 * to request TX callback for hostapd. BIT(1) is checked.
1596 if ((fc & BIT(1)) == BIT(1)) {
1597 pkt_data->flags |= IEEE80211_TXPD_REQ_TX_STATUS;
1599 hdr->frame_control = cpu_to_le16(fc);
1602 if (!(fc & IEEE80211_FCTL_PROTECTED))
1603 pkt_data->flags |= IEEE80211_TXPD_DO_NOT_ENCRYPT;
1605 sdata->stats.tx_packets++;
1606 sdata->stats.tx_bytes += skb->len;
1608 dev_queue_xmit(skb);
1613 /* helper functions for pending packets for when queues are stopped */
1615 void ieee80211_clear_tx_pending(struct ieee80211_local *local)
1618 struct ieee80211_tx_stored_packet *store;
1620 for (i = 0; i < local->hw.queues; i++) {
1621 if (!__ieee80211_queue_pending(local, i))
1623 store = &local->pending_packet[i];
1624 kfree_skb(store->skb);
1625 for (j = 0; j < store->num_extra_frag; j++)
1626 kfree_skb(store->extra_frag[j]);
1627 kfree(store->extra_frag);
1628 clear_bit(IEEE80211_LINK_STATE_PENDING, &local->state[i]);
1632 void ieee80211_tx_pending(unsigned long data)
1634 struct ieee80211_local *local = (struct ieee80211_local *)data;
1635 struct net_device *dev = local->mdev;
1636 struct ieee80211_tx_stored_packet *store;
1637 struct ieee80211_txrx_data tx;
1638 int i, ret, reschedule = 0;
1640 netif_tx_lock_bh(dev);
1641 for (i = 0; i < local->hw.queues; i++) {
1642 if (__ieee80211_queue_stopped(local, i))
1644 if (!__ieee80211_queue_pending(local, i)) {
1648 store = &local->pending_packet[i];
1649 tx.u.tx.control = &store->control;
1650 tx.u.tx.extra_frag = store->extra_frag;
1651 tx.u.tx.num_extra_frag = store->num_extra_frag;
1652 tx.u.tx.last_frag_hwrate = store->last_frag_hwrate;
1653 tx.u.tx.last_frag_rate = store->last_frag_rate;
1655 if (store->last_frag_rate_ctrl_probe)
1656 tx.flags |= IEEE80211_TXRXD_TXPROBE_LAST_FRAG;
1657 ret = __ieee80211_tx(local, store->skb, &tx);
1659 if (ret == IEEE80211_TX_FRAG_AGAIN)
1662 clear_bit(IEEE80211_LINK_STATE_PENDING,
1667 netif_tx_unlock_bh(dev);
1669 if (!ieee80211_qdisc_installed(dev)) {
1670 if (!__ieee80211_queue_stopped(local, 0))
1671 netif_wake_queue(dev);
1673 netif_schedule(dev);
1677 /* functions for drivers to get certain frames */
1679 static void ieee80211_beacon_add_tim(struct ieee80211_local *local,
1680 struct ieee80211_if_ap *bss,
1681 struct sk_buff *skb)
1685 int i, have_bits = 0, n1, n2;
1687 /* Generate bitmap for TIM only if there are any STAs in power save
1689 read_lock_bh(&local->sta_lock);
1690 if (atomic_read(&bss->num_sta_ps) > 0)
1691 /* in the hope that this is faster than
1692 * checking byte-for-byte */
1693 have_bits = !bitmap_empty((unsigned long*)bss->tim,
1694 IEEE80211_MAX_AID+1);
1696 if (bss->dtim_count == 0)
1697 bss->dtim_count = bss->dtim_period - 1;
1701 tim = pos = (u8 *) skb_put(skb, 6);
1702 *pos++ = WLAN_EID_TIM;
1704 *pos++ = bss->dtim_count;
1705 *pos++ = bss->dtim_period;
1707 if (bss->dtim_count == 0 && !skb_queue_empty(&bss->ps_bc_buf))
1711 /* Find largest even number N1 so that bits numbered 1 through
1712 * (N1 x 8) - 1 in the bitmap are 0 and number N2 so that bits
1713 * (N2 + 1) x 8 through 2007 are 0. */
1715 for (i = 0; i < IEEE80211_MAX_TIM_LEN; i++) {
1722 for (i = IEEE80211_MAX_TIM_LEN - 1; i >= n1; i--) {
1729 /* Bitmap control */
1731 /* Part Virt Bitmap */
1732 memcpy(pos, bss->tim + n1, n2 - n1 + 1);
1734 tim[1] = n2 - n1 + 4;
1735 skb_put(skb, n2 - n1);
1737 *pos++ = aid0; /* Bitmap control */
1738 *pos++ = 0; /* Part Virt Bitmap */
1740 read_unlock_bh(&local->sta_lock);
1743 struct sk_buff *ieee80211_beacon_get(struct ieee80211_hw *hw, int if_id,
1744 struct ieee80211_tx_control *control)
1746 struct ieee80211_local *local = hw_to_local(hw);
1747 struct sk_buff *skb;
1748 struct net_device *bdev;
1749 struct ieee80211_sub_if_data *sdata = NULL;
1750 struct ieee80211_if_ap *ap = NULL;
1751 struct ieee80211_rate *rate;
1752 struct rate_control_extra extra;
1753 u8 *b_head, *b_tail;
1756 bdev = dev_get_by_index(&init_net, if_id);
1758 sdata = IEEE80211_DEV_TO_SUB_IF(bdev);
1763 if (!ap || sdata->type != IEEE80211_IF_TYPE_AP ||
1765 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
1766 if (net_ratelimit())
1767 printk(KERN_DEBUG "no beacon data avail for idx=%d "
1768 "(%s)\n", if_id, bdev ? bdev->name : "N/A");
1769 #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */
1773 /* Assume we are generating the normal beacon locally */
1774 b_head = ap->beacon_head;
1775 b_tail = ap->beacon_tail;
1776 bh_len = ap->beacon_head_len;
1777 bt_len = ap->beacon_tail_len;
1779 skb = dev_alloc_skb(local->tx_headroom +
1780 bh_len + bt_len + 256 /* maximum TIM len */);
1784 skb_reserve(skb, local->tx_headroom);
1785 memcpy(skb_put(skb, bh_len), b_head, bh_len);
1787 ieee80211_include_sequence(sdata, (struct ieee80211_hdr *)skb->data);
1789 ieee80211_beacon_add_tim(local, ap, skb);
1792 memcpy(skb_put(skb, bt_len), b_tail, bt_len);
1796 memset(&extra, 0, sizeof(extra));
1797 extra.mode = local->oper_hw_mode;
1799 rate = rate_control_get_rate(local, local->mdev, skb, &extra);
1801 if (net_ratelimit()) {
1802 printk(KERN_DEBUG "%s: ieee80211_beacon_get: no rate "
1803 "found\n", local->mdev->name);
1810 ((sdata->flags & IEEE80211_SDATA_SHORT_PREAMBLE) &&
1811 (rate->flags & IEEE80211_RATE_PREAMBLE2)) ?
1812 rate->val2 : rate->val;
1813 control->antenna_sel_tx = local->hw.conf.antenna_sel_tx;
1814 control->power_level = local->hw.conf.power_level;
1815 control->flags |= IEEE80211_TXCTL_NO_ACK;
1816 control->retry_limit = 1;
1817 control->flags |= IEEE80211_TXCTL_CLEAR_DST_MASK;
1823 EXPORT_SYMBOL(ieee80211_beacon_get);
1825 void ieee80211_rts_get(struct ieee80211_hw *hw, int if_id,
1826 const void *frame, size_t frame_len,
1827 const struct ieee80211_tx_control *frame_txctl,
1828 struct ieee80211_rts *rts)
1830 const struct ieee80211_hdr *hdr = frame;
1833 fctl = IEEE80211_FTYPE_CTL | IEEE80211_STYPE_RTS;
1834 rts->frame_control = cpu_to_le16(fctl);
1835 rts->duration = ieee80211_rts_duration(hw, if_id, frame_len, frame_txctl);
1836 memcpy(rts->ra, hdr->addr1, sizeof(rts->ra));
1837 memcpy(rts->ta, hdr->addr2, sizeof(rts->ta));
1839 EXPORT_SYMBOL(ieee80211_rts_get);
1841 void ieee80211_ctstoself_get(struct ieee80211_hw *hw, int if_id,
1842 const void *frame, size_t frame_len,
1843 const struct ieee80211_tx_control *frame_txctl,
1844 struct ieee80211_cts *cts)
1846 const struct ieee80211_hdr *hdr = frame;
1849 fctl = IEEE80211_FTYPE_CTL | IEEE80211_STYPE_CTS;
1850 cts->frame_control = cpu_to_le16(fctl);
1851 cts->duration = ieee80211_ctstoself_duration(hw, if_id, frame_len, frame_txctl);
1852 memcpy(cts->ra, hdr->addr1, sizeof(cts->ra));
1854 EXPORT_SYMBOL(ieee80211_ctstoself_get);
1857 ieee80211_get_buffered_bc(struct ieee80211_hw *hw, int if_id,
1858 struct ieee80211_tx_control *control)
1860 struct ieee80211_local *local = hw_to_local(hw);
1861 struct sk_buff *skb;
1862 struct sta_info *sta;
1863 ieee80211_tx_handler *handler;
1864 struct ieee80211_txrx_data tx;
1865 ieee80211_txrx_result res = TXRX_DROP;
1866 struct net_device *bdev;
1867 struct ieee80211_sub_if_data *sdata;
1868 struct ieee80211_if_ap *bss = NULL;
1870 bdev = dev_get_by_index(&init_net, if_id);
1872 sdata = IEEE80211_DEV_TO_SUB_IF(bdev);
1876 if (!bss || sdata->type != IEEE80211_IF_TYPE_AP || !bss->beacon_head)
1879 if (bss->dtim_count != 0)
1880 return NULL; /* send buffered bc/mc only after DTIM beacon */
1881 memset(control, 0, sizeof(*control));
1883 skb = skb_dequeue(&bss->ps_bc_buf);
1886 local->total_ps_buffered--;
1888 if (!skb_queue_empty(&bss->ps_bc_buf) && skb->len >= 2) {
1889 struct ieee80211_hdr *hdr =
1890 (struct ieee80211_hdr *) skb->data;
1891 /* more buffered multicast/broadcast frames ==> set
1892 * MoreData flag in IEEE 802.11 header to inform PS
1894 hdr->frame_control |=
1895 cpu_to_le16(IEEE80211_FCTL_MOREDATA);
1898 if (ieee80211_tx_prepare(&tx, skb, local->mdev, control) == 0)
1900 dev_kfree_skb_any(skb);
1903 tx.flags |= IEEE80211_TXRXD_TXPS_BUFFERED;
1905 for (handler = local->tx_handlers; *handler != NULL; handler++) {
1906 res = (*handler)(&tx);
1907 if (res == TXRX_DROP || res == TXRX_QUEUED)
1911 skb = tx.skb; /* handlers are allowed to change skb */
1913 if (res == TXRX_DROP) {
1914 I802_DEBUG_INC(local->tx_handlers_drop);
1917 } else if (res == TXRX_QUEUED) {
1918 I802_DEBUG_INC(local->tx_handlers_queued);
1927 EXPORT_SYMBOL(ieee80211_get_buffered_bc);