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linux/net/mac80211/tx.c
Johannes Berg fc8a7321d3 mac80211: don't expose ieee80211_add_srates_ie() 
This and ieee80211_add_ext_srates_ie() aren't
exported, so can't be used by drivers anyway,
but there's also no reason that they should be
so make them private to mac80211 and use sdata
instead of vif arguments.

Acked-by: Arik Nemtsov <arik@wizery.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2012-06-28 10:35:50 +02:00

2737 lines
75 KiB
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/*
* Copyright 2002-2005, Instant802 Networks, Inc.
* Copyright 2005-2006, Devicescape Software, Inc.
* Copyright 2006-2007 Jiri Benc <jbenc@suse.cz>
* Copyright 2007 Johannes Berg <johannes@sipsolutions.net>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
*
* Transmit and frame generation functions.
*/
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/skbuff.h>
#include <linux/etherdevice.h>
#include <linux/bitmap.h>
#include <linux/rcupdate.h>
#include <linux/export.h>
#include <net/net_namespace.h>
#include <net/ieee80211_radiotap.h>
#include <net/cfg80211.h>
#include <net/mac80211.h>
#include <asm/unaligned.h>
#include "ieee80211_i.h"
#include "driver-ops.h"
#include "led.h"
#include "mesh.h"
#include "wep.h"
#include "wpa.h"
#include "wme.h"
#include "rate.h"
/* misc utils */
static __le16 ieee80211_duration(struct ieee80211_tx_data *tx,
struct sk_buff *skb, int group_addr,
int next_frag_len)
{
int rate, mrate, erp, dur, i;
struct ieee80211_rate *txrate;
struct ieee80211_local *local = tx->local;
struct ieee80211_supported_band *sband;
struct ieee80211_hdr *hdr;
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
/* assume HW handles this */
if (info->control.rates[0].flags & IEEE80211_TX_RC_MCS)
return 0;
/* uh huh? */
if (WARN_ON_ONCE(info->control.rates[0].idx < 0))
return 0;
sband = local->hw.wiphy->bands[tx->channel->band];
txrate = &sband->bitrates[info->control.rates[0].idx];
erp = txrate->flags & IEEE80211_RATE_ERP_G;
/*
* data and mgmt (except PS Poll):
* - during CFP: 32768
* - during contention period:
* if addr1 is group address: 0
* if more fragments = 0 and addr1 is individual address: time to
* transmit one ACK plus SIFS
* if more fragments = 1 and addr1 is individual address: time to
* transmit next fragment plus 2 x ACK plus 3 x SIFS
*
* IEEE 802.11, 9.6:
* - control response frame (CTS or ACK) shall be transmitted using the
* same rate as the immediately previous frame in the frame exchange
* sequence, if this rate belongs to the PHY mandatory rates, or else
* at the highest possible rate belonging to the PHY rates in the
* BSSBasicRateSet
*/
hdr = (struct ieee80211_hdr *)skb->data;
if (ieee80211_is_ctl(hdr->frame_control)) {
/* TODO: These control frames are not currently sent by
* mac80211, but should they be implemented, this function
* needs to be updated to support duration field calculation.
*
* RTS: time needed to transmit pending data/mgmt frame plus
* one CTS frame plus one ACK frame plus 3 x SIFS
* CTS: duration of immediately previous RTS minus time
* required to transmit CTS and its SIFS
* ACK: 0 if immediately previous directed data/mgmt had
* more=0, with more=1 duration in ACK frame is duration
* from previous frame minus time needed to transmit ACK
* and its SIFS
* PS Poll: BIT(15) | BIT(14) | aid
*/
return 0;
}
/* data/mgmt */
if (0 /* FIX: data/mgmt during CFP */)
return cpu_to_le16(32768);
if (group_addr) /* Group address as the destination - no ACK */
return 0;
/* Individual destination address:
* IEEE 802.11, Ch. 9.6 (after IEEE 802.11g changes)
* CTS and ACK frames shall be transmitted using the highest rate in
* basic rate set that is less than or equal to the rate of the
* immediately previous frame and that is using the same modulation
* (CCK or OFDM). If no basic rate set matches with these requirements,
* the highest mandatory rate of the PHY that is less than or equal to
* the rate of the previous frame is used.
* Mandatory rates for IEEE 802.11g PHY: 1, 2, 5.5, 11, 6, 12, 24 Mbps
*/
rate = -1;
/* use lowest available if everything fails */
mrate = sband->bitrates[0].bitrate;
for (i = 0; i < sband->n_bitrates; i++) {
struct ieee80211_rate *r = &sband->bitrates[i];
if (r->bitrate > txrate->bitrate)
break;
if (tx->sdata->vif.bss_conf.basic_rates & BIT(i))
rate = r->bitrate;
switch (sband->band) {
case IEEE80211_BAND_2GHZ: {
u32 flag;
if (tx->sdata->flags & IEEE80211_SDATA_OPERATING_GMODE)
flag = IEEE80211_RATE_MANDATORY_G;
else
flag = IEEE80211_RATE_MANDATORY_B;
if (r->flags & flag)
mrate = r->bitrate;
break;
}
case IEEE80211_BAND_5GHZ:
if (r->flags & IEEE80211_RATE_MANDATORY_A)
mrate = r->bitrate;
break;
case IEEE80211_NUM_BANDS:
WARN_ON(1);
break;
}
}
if (rate == -1) {
/* No matching basic rate found; use highest suitable mandatory
* PHY rate */
rate = mrate;
}
/* Don't calculate ACKs for QoS Frames with NoAck Policy set */
if (ieee80211_is_data_qos(hdr->frame_control) &&
*(ieee80211_get_qos_ctl(hdr)) & IEEE80211_QOS_CTL_ACK_POLICY_NOACK)
dur = 0;
else
/* Time needed to transmit ACK
* (10 bytes + 4-byte FCS = 112 bits) plus SIFS; rounded up
* to closest integer */
dur = ieee80211_frame_duration(sband->band, 10, rate, erp,
tx->sdata->vif.bss_conf.use_short_preamble);
if (next_frag_len) {
/* Frame is fragmented: duration increases with time needed to
* transmit next fragment plus ACK and 2 x SIFS. */
dur *= 2; /* ACK + SIFS */
/* next fragment */
dur += ieee80211_frame_duration(sband->band, next_frag_len,
txrate->bitrate, erp,
tx->sdata->vif.bss_conf.use_short_preamble);
}
return cpu_to_le16(dur);
}
/* tx handlers */
static ieee80211_tx_result debug_noinline
ieee80211_tx_h_dynamic_ps(struct ieee80211_tx_data *tx)
{
struct ieee80211_local *local = tx->local;
struct ieee80211_if_managed *ifmgd;
/* driver doesn't support power save */
if (!(local->hw.flags & IEEE80211_HW_SUPPORTS_PS))
return TX_CONTINUE;
/* hardware does dynamic power save */
if (local->hw.flags & IEEE80211_HW_SUPPORTS_DYNAMIC_PS)
return TX_CONTINUE;
/* dynamic power save disabled */
if (local->hw.conf.dynamic_ps_timeout <= 0)
return TX_CONTINUE;
/* we are scanning, don't enable power save */
if (local->scanning)
return TX_CONTINUE;
if (!local->ps_sdata)
return TX_CONTINUE;
/* No point if we're going to suspend */
if (local->quiescing)
return TX_CONTINUE;
/* dynamic ps is supported only in managed mode */
if (tx->sdata->vif.type != NL80211_IFTYPE_STATION)
return TX_CONTINUE;
ifmgd = &tx->sdata->u.mgd;
/*
* Don't wakeup from power save if u-apsd is enabled, voip ac has
* u-apsd enabled and the frame is in voip class. This effectively
* means that even if all access categories have u-apsd enabled, in
* practise u-apsd is only used with the voip ac. This is a
* workaround for the case when received voip class packets do not
* have correct qos tag for some reason, due the network or the
* peer application.
*
* Note: ifmgd->uapsd_queues access is racy here. If the value is
* changed via debugfs, user needs to reassociate manually to have
* everything in sync.
*/
if ((ifmgd->flags & IEEE80211_STA_UAPSD_ENABLED) &&
(ifmgd->uapsd_queues & IEEE80211_WMM_IE_STA_QOSINFO_AC_VO) &&
skb_get_queue_mapping(tx->skb) == IEEE80211_AC_VO)
return TX_CONTINUE;
if (local->hw.conf.flags & IEEE80211_CONF_PS) {
ieee80211_stop_queues_by_reason(&local->hw,
IEEE80211_QUEUE_STOP_REASON_PS);
ifmgd->flags &= ~IEEE80211_STA_NULLFUNC_ACKED;
ieee80211_queue_work(&local->hw,
&local->dynamic_ps_disable_work);
}
/* Don't restart the timer if we're not disassociated */
if (!ifmgd->associated)
return TX_CONTINUE;
mod_timer(&local->dynamic_ps_timer, jiffies +
msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout));
return TX_CONTINUE;
}
static ieee80211_tx_result debug_noinline
ieee80211_tx_h_check_assoc(struct ieee80211_tx_data *tx)
{
struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
bool assoc = false;
if (unlikely(info->flags & IEEE80211_TX_CTL_INJECTED))
return TX_CONTINUE;
if (unlikely(test_bit(SCAN_SW_SCANNING, &tx->local->scanning)) &&
test_bit(SDATA_STATE_OFFCHANNEL, &tx->sdata->state) &&
!ieee80211_is_probe_req(hdr->frame_control) &&
!ieee80211_is_nullfunc(hdr->frame_control))
/*
* When software scanning only nullfunc frames (to notify
* the sleep state to the AP) and probe requests (for the
* active scan) are allowed, all other frames should not be
* sent and we should not get here, but if we do
* nonetheless, drop them to avoid sending them
* off-channel. See the link below and
* ieee80211_start_scan() for more.
*
* http://article.gmane.org/gmane.linux.kernel.wireless.general/30089
*/
return TX_DROP;
if (tx->sdata->vif.type == NL80211_IFTYPE_WDS)
return TX_CONTINUE;
if (tx->sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
return TX_CONTINUE;
if (tx->flags & IEEE80211_TX_PS_BUFFERED)
return TX_CONTINUE;
if (tx->sta)
assoc = test_sta_flag(tx->sta, WLAN_STA_ASSOC);
if (likely(tx->flags & IEEE80211_TX_UNICAST)) {
if (unlikely(!assoc &&
ieee80211_is_data(hdr->frame_control))) {
#ifdef CONFIG_MAC80211_VERBOSE_DEBUG
sdata_info(tx->sdata,
"dropped data frame to not associated station %pM\n",
hdr->addr1);
#endif
I802_DEBUG_INC(tx->local->tx_handlers_drop_not_assoc);
return TX_DROP;
}
} else if (unlikely(tx->sdata->vif.type == NL80211_IFTYPE_AP &&
ieee80211_is_data(hdr->frame_control) &&
!atomic_read(&tx->sdata->u.ap.num_mcast_sta))) {
/*
* No associated STAs - no need to send multicast
* frames.
*/
return TX_DROP;
}
return TX_CONTINUE;
}
/* This function is called whenever the AP is about to exceed the maximum limit
* of buffered frames for power saving STAs. This situation should not really
* happen often during normal operation, so dropping the oldest buffered packet
* from each queue should be OK to make some room for new frames. */
static void purge_old_ps_buffers(struct ieee80211_local *local)
{
int total = 0, purged = 0;
struct sk_buff *skb;
struct ieee80211_sub_if_data *sdata;
struct sta_info *sta;
/*
* virtual interfaces are protected by RCU
*/
rcu_read_lock();
list_for_each_entry_rcu(sdata, &local->interfaces, list) {
struct ieee80211_if_ap *ap;
if (sdata->vif.type != NL80211_IFTYPE_AP)
continue;
ap = &sdata->u.ap;
skb = skb_dequeue(&ap->ps_bc_buf);
if (skb) {
purged++;
dev_kfree_skb(skb);
}
total += skb_queue_len(&ap->ps_bc_buf);
}
/*
* Drop one frame from each station from the lowest-priority
* AC that has frames at all.
*/
list_for_each_entry_rcu(sta, &local->sta_list, list) {
int ac;
for (ac = IEEE80211_AC_BK; ac >= IEEE80211_AC_VO; ac--) {
skb = skb_dequeue(&sta->ps_tx_buf[ac]);
total += skb_queue_len(&sta->ps_tx_buf[ac]);
if (skb) {
purged++;
dev_kfree_skb(skb);
break;
}
}
}
rcu_read_unlock();
local->total_ps_buffered = total;
ps_dbg_hw(&local->hw, "PS buffers full - purged %d frames\n", purged);
}
static ieee80211_tx_result
ieee80211_tx_h_multicast_ps_buf(struct ieee80211_tx_data *tx)
{
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
/*
* broadcast/multicast frame
*
* If any of the associated stations is in power save mode,
* the frame is buffered to be sent after DTIM beacon frame.
* This is done either by the hardware or us.
*/
/* powersaving STAs only in AP/VLAN mode */
if (!tx->sdata->bss)
return TX_CONTINUE;
/* no buffering for ordered frames */
if (ieee80211_has_order(hdr->frame_control))
return TX_CONTINUE;
/* no stations in PS mode */
if (!atomic_read(&tx->sdata->bss->num_sta_ps))
return TX_CONTINUE;
info->flags |= IEEE80211_TX_CTL_SEND_AFTER_DTIM;
if (tx->local->hw.flags & IEEE80211_HW_QUEUE_CONTROL)
info->hw_queue = tx->sdata->vif.cab_queue;
/* device releases frame after DTIM beacon */
if (!(tx->local->hw.flags & IEEE80211_HW_HOST_BROADCAST_PS_BUFFERING))
return TX_CONTINUE;
/* buffered in mac80211 */
if (tx->local->total_ps_buffered >= TOTAL_MAX_TX_BUFFER)
purge_old_ps_buffers(tx->local);
if (skb_queue_len(&tx->sdata->bss->ps_bc_buf) >= AP_MAX_BC_BUFFER) {
ps_dbg(tx->sdata,
"BC TX buffer full - dropping the oldest frame\n");
dev_kfree_skb(skb_dequeue(&tx->sdata->bss->ps_bc_buf));
} else
tx->local->total_ps_buffered++;
skb_queue_tail(&tx->sdata->bss->ps_bc_buf, tx->skb);
return TX_QUEUED;
}
static int ieee80211_use_mfp(__le16 fc, struct sta_info *sta,
struct sk_buff *skb)
{
if (!ieee80211_is_mgmt(fc))
return 0;
if (sta == NULL || !test_sta_flag(sta, WLAN_STA_MFP))
return 0;
if (!ieee80211_is_robust_mgmt_frame((struct ieee80211_hdr *)
skb->data))
return 0;
return 1;
}
static ieee80211_tx_result
ieee80211_tx_h_unicast_ps_buf(struct ieee80211_tx_data *tx)
{
struct sta_info *sta = tx->sta;
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
struct ieee80211_local *local = tx->local;
if (unlikely(!sta))
return TX_CONTINUE;
if (unlikely((test_sta_flag(sta, WLAN_STA_PS_STA) ||
test_sta_flag(sta, WLAN_STA_PS_DRIVER)) &&
!(info->flags & IEEE80211_TX_CTL_NO_PS_BUFFER))) {
int ac = skb_get_queue_mapping(tx->skb);
/* only deauth, disassoc and action are bufferable MMPDUs */
if (ieee80211_is_mgmt(hdr->frame_control) &&
!ieee80211_is_deauth(hdr->frame_control) &&
!ieee80211_is_disassoc(hdr->frame_control) &&
!ieee80211_is_action(hdr->frame_control)) {
info->flags |= IEEE80211_TX_CTL_NO_PS_BUFFER;
return TX_CONTINUE;
}
ps_dbg(sta->sdata, "STA %pM aid %d: PS buffer for AC %d\n",
sta->sta.addr, sta->sta.aid, ac);
if (tx->local->total_ps_buffered >= TOTAL_MAX_TX_BUFFER)
purge_old_ps_buffers(tx->local);
if (skb_queue_len(&sta->ps_tx_buf[ac]) >= STA_MAX_TX_BUFFER) {
struct sk_buff *old = skb_dequeue(&sta->ps_tx_buf[ac]);
ps_dbg(tx->sdata,
"STA %pM TX buffer for AC %d full - dropping oldest frame\n",
sta->sta.addr, ac);
dev_kfree_skb(old);
} else
tx->local->total_ps_buffered++;
info->control.jiffies = jiffies;
info->control.vif = &tx->sdata->vif;
info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
skb_queue_tail(&sta->ps_tx_buf[ac], tx->skb);
if (!timer_pending(&local->sta_cleanup))
mod_timer(&local->sta_cleanup,
round_jiffies(jiffies +
STA_INFO_CLEANUP_INTERVAL));
/*
* We queued up some frames, so the TIM bit might
* need to be set, recalculate it.
*/
sta_info_recalc_tim(sta);
return TX_QUEUED;
} else if (unlikely(test_sta_flag(sta, WLAN_STA_PS_STA))) {
ps_dbg(tx->sdata,
"STA %pM in PS mode, but polling/in SP -> send frame\n",
sta->sta.addr);
}
return TX_CONTINUE;
}
static ieee80211_tx_result debug_noinline
ieee80211_tx_h_ps_buf(struct ieee80211_tx_data *tx)
{
if (unlikely(tx->flags & IEEE80211_TX_PS_BUFFERED))
return TX_CONTINUE;
if (tx->flags & IEEE80211_TX_UNICAST)
return ieee80211_tx_h_unicast_ps_buf(tx);
else
return ieee80211_tx_h_multicast_ps_buf(tx);
}
static ieee80211_tx_result debug_noinline
ieee80211_tx_h_check_control_port_protocol(struct ieee80211_tx_data *tx)
{
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
if (unlikely(tx->sdata->control_port_protocol == tx->skb->protocol &&
tx->sdata->control_port_no_encrypt))
info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
return TX_CONTINUE;
}
static ieee80211_tx_result debug_noinline
ieee80211_tx_h_select_key(struct ieee80211_tx_data *tx)
{
struct ieee80211_key *key = NULL;
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
if (unlikely(info->flags & IEEE80211_TX_INTFL_DONT_ENCRYPT))
tx->key = NULL;
else if (tx->sta && (key = rcu_dereference(tx->sta->ptk)))
tx->key = key;
else if (ieee80211_is_mgmt(hdr->frame_control) &&
is_multicast_ether_addr(hdr->addr1) &&
ieee80211_is_robust_mgmt_frame(hdr) &&
(key = rcu_dereference(tx->sdata->default_mgmt_key)))
tx->key = key;
else if (is_multicast_ether_addr(hdr->addr1) &&
(key = rcu_dereference(tx->sdata->default_multicast_key)))
tx->key = key;
else if (!is_multicast_ether_addr(hdr->addr1) &&
(key = rcu_dereference(tx->sdata->default_unicast_key)))
tx->key = key;
else if (tx->sdata->drop_unencrypted &&
(tx->skb->protocol != tx->sdata->control_port_protocol) &&
!(info->flags & IEEE80211_TX_CTL_INJECTED) &&
(!ieee80211_is_robust_mgmt_frame(hdr) ||
(ieee80211_is_action(hdr->frame_control) &&
tx->sta && test_sta_flag(tx->sta, WLAN_STA_MFP)))) {
I802_DEBUG_INC(tx->local->tx_handlers_drop_unencrypted);
return TX_DROP;
} else
tx->key = NULL;
if (tx->key) {
bool skip_hw = false;
tx->key->tx_rx_count++;
/* TODO: add threshold stuff again */
switch (tx->key->conf.cipher) {
case WLAN_CIPHER_SUITE_WEP40:
case WLAN_CIPHER_SUITE_WEP104:
case WLAN_CIPHER_SUITE_TKIP:
if (!ieee80211_is_data_present(hdr->frame_control))
tx->key = NULL;
break;
case WLAN_CIPHER_SUITE_CCMP:
if (!ieee80211_is_data_present(hdr->frame_control) &&
!ieee80211_use_mfp(hdr->frame_control, tx->sta,
tx->skb))
tx->key = NULL;
else
skip_hw = (tx->key->conf.flags &
IEEE80211_KEY_FLAG_SW_MGMT) &&
ieee80211_is_mgmt(hdr->frame_control);
break;
case WLAN_CIPHER_SUITE_AES_CMAC:
if (!ieee80211_is_mgmt(hdr->frame_control))
tx->key = NULL;
break;
}
if (unlikely(tx->key && tx->key->flags & KEY_FLAG_TAINTED))
return TX_DROP;
if (!skip_hw && tx->key &&
tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE)
info->control.hw_key = &tx->key->conf;
}
return TX_CONTINUE;
}
static ieee80211_tx_result debug_noinline
ieee80211_tx_h_rate_ctrl(struct ieee80211_tx_data *tx)
{
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
struct ieee80211_hdr *hdr = (void *)tx->skb->data;
struct ieee80211_supported_band *sband;
struct ieee80211_rate *rate;
int i;
u32 len;
bool inval = false, rts = false, short_preamble = false;
struct ieee80211_tx_rate_control txrc;
bool assoc = false;
memset(&txrc, 0, sizeof(txrc));
sband = tx->local->hw.wiphy->bands[tx->channel->band];
len = min_t(u32, tx->skb->len + FCS_LEN,
tx->local->hw.wiphy->frag_threshold);
/* set up the tx rate control struct we give the RC algo */
txrc.hw = &tx->local->hw;
txrc.sband = sband;
txrc.bss_conf = &tx->sdata->vif.bss_conf;
txrc.skb = tx->skb;
txrc.reported_rate.idx = -1;
txrc.rate_idx_mask = tx->sdata->rc_rateidx_mask[tx->channel->band];
if (txrc.rate_idx_mask == (1 << sband->n_bitrates) - 1)
txrc.max_rate_idx = -1;
else
txrc.max_rate_idx = fls(txrc.rate_idx_mask) - 1;
memcpy(txrc.rate_idx_mcs_mask,
tx->sdata->rc_rateidx_mcs_mask[tx->channel->band],
sizeof(txrc.rate_idx_mcs_mask));
txrc.bss = (tx->sdata->vif.type == NL80211_IFTYPE_AP ||
tx->sdata->vif.type == NL80211_IFTYPE_MESH_POINT ||
tx->sdata->vif.type == NL80211_IFTYPE_ADHOC);
/* set up RTS protection if desired */
if (len > tx->local->hw.wiphy->rts_threshold) {
txrc.rts = rts = true;
}
/*
* Use short preamble if the BSS can handle it, but not for
* management frames unless we know the receiver can handle
* that -- the management frame might be to a station that
* just wants a probe response.
*/
if (tx->sdata->vif.bss_conf.use_short_preamble &&
(ieee80211_is_data(hdr->frame_control) ||
(tx->sta && test_sta_flag(tx->sta, WLAN_STA_SHORT_PREAMBLE))))
txrc.short_preamble = short_preamble = true;
if (tx->sta)
assoc = test_sta_flag(tx->sta, WLAN_STA_ASSOC);
/*
* Lets not bother rate control if we're associated and cannot
* talk to the sta. This should not happen.
*/
if (WARN(test_bit(SCAN_SW_SCANNING, &tx->local->scanning) && assoc &&
!rate_usable_index_exists(sband, &tx->sta->sta),
"%s: Dropped data frame as no usable bitrate found while "
"scanning and associated. Target station: "
"%pM on %d GHz band\n",
tx->sdata->name, hdr->addr1,
tx->channel->band ? 5 : 2))
return TX_DROP;
/*
* If we're associated with the sta at this point we know we can at
* least send the frame at the lowest bit rate.
*/
rate_control_get_rate(tx->sdata, tx->sta, &txrc);
if (unlikely(info->control.rates[0].idx < 0))
return TX_DROP;
if (txrc.reported_rate.idx < 0) {
txrc.reported_rate = info->control.rates[0];
if (tx->sta && ieee80211_is_data(hdr->frame_control))
tx->sta->last_tx_rate = txrc.reported_rate;
} else if (tx->sta)
tx->sta->last_tx_rate = txrc.reported_rate;
if (unlikely(!info->control.rates[0].count))
info->control.rates[0].count = 1;
if (WARN_ON_ONCE((info->control.rates[0].count > 1) &&
(info->flags & IEEE80211_TX_CTL_NO_ACK)))
info->control.rates[0].count = 1;
if (is_multicast_ether_addr(hdr->addr1)) {
/*
* XXX: verify the rate is in the basic rateset
*/
return TX_CONTINUE;
}
/*
* set up the RTS/CTS rate as the fastest basic rate
* that is not faster than the data rate
*
* XXX: Should this check all retry rates?
*/
if (!(info->control.rates[0].flags & IEEE80211_TX_RC_MCS)) {
s8 baserate = 0;
rate = &sband->bitrates[info->control.rates[0].idx];
for (i = 0; i < sband->n_bitrates; i++) {
/* must be a basic rate */
if (!(tx->sdata->vif.bss_conf.basic_rates & BIT(i)))
continue;
/* must not be faster than the data rate */
if (sband->bitrates[i].bitrate > rate->bitrate)
continue;
/* maximum */
if (sband->bitrates[baserate].bitrate <
sband->bitrates[i].bitrate)
baserate = i;
}
info->control.rts_cts_rate_idx = baserate;
}
for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) {
/*
* make sure there's no valid rate following
* an invalid one, just in case drivers don't
* take the API seriously to stop at -1.
*/
if (inval) {
info->control.rates[i].idx = -1;
continue;
}
if (info->control.rates[i].idx < 0) {
inval = true;
continue;
}
/*
* For now assume MCS is already set up correctly, this
* needs to be fixed.
*/
if (info->control.rates[i].flags & IEEE80211_TX_RC_MCS) {
WARN_ON(info->control.rates[i].idx > 76);
continue;
}
/* set up RTS protection if desired */
if (rts)
info->control.rates[i].flags |=
IEEE80211_TX_RC_USE_RTS_CTS;
/* RC is busted */
if (WARN_ON_ONCE(info->control.rates[i].idx >=
sband->n_bitrates)) {
info->control.rates[i].idx = -1;
continue;
}
rate = &sband->bitrates[info->control.rates[i].idx];
/* set up short preamble */
if (short_preamble &&
rate->flags & IEEE80211_RATE_SHORT_PREAMBLE)
info->control.rates[i].flags |=
IEEE80211_TX_RC_USE_SHORT_PREAMBLE;
/* set up G protection */
if (!rts && tx->sdata->vif.bss_conf.use_cts_prot &&
rate->flags & IEEE80211_RATE_ERP_G)
info->control.rates[i].flags |=
IEEE80211_TX_RC_USE_CTS_PROTECT;
}
return TX_CONTINUE;
}
static ieee80211_tx_result debug_noinline
ieee80211_tx_h_sequence(struct ieee80211_tx_data *tx)
{
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
u16 *seq;
u8 *qc;
int tid;
/*
* Packet injection may want to control the sequence
* number, if we have no matching interface then we
* neither assign one ourselves nor ask the driver to.
*/
if (unlikely(info->control.vif->type == NL80211_IFTYPE_MONITOR))
return TX_CONTINUE;
if (unlikely(ieee80211_is_ctl(hdr->frame_control)))
return TX_CONTINUE;
if (ieee80211_hdrlen(hdr->frame_control) < 24)
return TX_CONTINUE;
if (ieee80211_is_qos_nullfunc(hdr->frame_control))
return TX_CONTINUE;
/*
* Anything but QoS data that has a sequence number field
* (is long enough) gets a sequence number from the global
* counter.
*/
if (!ieee80211_is_data_qos(hdr->frame_control)) {
/* driver should assign sequence number */
info->flags |= IEEE80211_TX_CTL_ASSIGN_SEQ;
/* for pure STA mode without beacons, we can do it */
hdr->seq_ctrl = cpu_to_le16(tx->sdata->sequence_number);
tx->sdata->sequence_number += 0x10;
return TX_CONTINUE;
}
/*
* This should be true for injected/management frames only, for
* management frames we have set the IEEE80211_TX_CTL_ASSIGN_SEQ
* above since they are not QoS-data frames.
*/
if (!tx->sta)
return TX_CONTINUE;
/* include per-STA, per-TID sequence counter */
qc = ieee80211_get_qos_ctl(hdr);
tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
seq = &tx->sta->tid_seq[tid];
hdr->seq_ctrl = cpu_to_le16(*seq);
/* Increase the sequence number. */
*seq = (*seq + 0x10) & IEEE80211_SCTL_SEQ;
return TX_CONTINUE;
}
static int ieee80211_fragment(struct ieee80211_tx_data *tx,
struct sk_buff *skb, int hdrlen,
int frag_threshold)
{
struct ieee80211_local *local = tx->local;
struct ieee80211_tx_info *info;
struct sk_buff *tmp;
int per_fragm = frag_threshold - hdrlen - FCS_LEN;
int pos = hdrlen + per_fragm;
int rem = skb->len - hdrlen - per_fragm;
if (WARN_ON(rem < 0))
return -EINVAL;
/* first fragment was already added to queue by caller */
while (rem) {
int fraglen = per_fragm;
if (fraglen > rem)
fraglen = rem;
rem -= fraglen;
tmp = dev_alloc_skb(local->tx_headroom +
frag_threshold +
IEEE80211_ENCRYPT_HEADROOM +
IEEE80211_ENCRYPT_TAILROOM);
if (!tmp)
return -ENOMEM;
__skb_queue_tail(&tx->skbs, tmp);
skb_reserve(tmp, local->tx_headroom +
IEEE80211_ENCRYPT_HEADROOM);
/* copy control information */
memcpy(tmp->cb, skb->cb, sizeof(tmp->cb));
info = IEEE80211_SKB_CB(tmp);
info->flags &= ~(IEEE80211_TX_CTL_CLEAR_PS_FILT |
IEEE80211_TX_CTL_FIRST_FRAGMENT);
if (rem)
info->flags |= IEEE80211_TX_CTL_MORE_FRAMES;
skb_copy_queue_mapping(tmp, skb);
tmp->priority = skb->priority;
tmp->dev = skb->dev;
/* copy header and data */
memcpy(skb_put(tmp, hdrlen), skb->data, hdrlen);
memcpy(skb_put(tmp, fraglen), skb->data + pos, fraglen);
pos += fraglen;
}
/* adjust first fragment's length */
skb->len = hdrlen + per_fragm;
return 0;
}
static ieee80211_tx_result debug_noinline
ieee80211_tx_h_fragment(struct ieee80211_tx_data *tx)
{
struct sk_buff *skb = tx->skb;
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
struct ieee80211_hdr *hdr = (void *)skb->data;
int frag_threshold = tx->local->hw.wiphy->frag_threshold;
int hdrlen;
int fragnum;
/* no matter what happens, tx->skb moves to tx->skbs */
__skb_queue_tail(&tx->skbs, skb);
tx->skb = NULL;
if (info->flags & IEEE80211_TX_CTL_DONTFRAG)
return TX_CONTINUE;
if (tx->local->ops->set_frag_threshold)
return TX_CONTINUE;
/*
* Warn when submitting a fragmented A-MPDU frame and drop it.
* This scenario is handled in ieee80211_tx_prepare but extra
* caution taken here as fragmented ampdu may cause Tx stop.
*/
if (WARN_ON(info->flags & IEEE80211_TX_CTL_AMPDU))
return TX_DROP;
hdrlen = ieee80211_hdrlen(hdr->frame_control);
/* internal error, why isn't DONTFRAG set? */
if (WARN_ON(skb->len + FCS_LEN <= frag_threshold))
return TX_DROP;
/*
* Now fragment the frame. This will allocate all the fragments and
* chain them (using skb as the first fragment) to skb->next.
* During transmission, we will remove the successfully transmitted
* fragments from this list. When the low-level driver rejects one
* of the fragments then we will simply pretend to accept the skb
* but store it away as pending.
*/
if (ieee80211_fragment(tx, skb, hdrlen, frag_threshold))
return TX_DROP;
/* update duration/seq/flags of fragments */
fragnum = 0;
skb_queue_walk(&tx->skbs, skb) {
int next_len;
const __le16 morefrags = cpu_to_le16(IEEE80211_FCTL_MOREFRAGS);
hdr = (void *)skb->data;
info = IEEE80211_SKB_CB(skb);
if (!skb_queue_is_last(&tx->skbs, skb)) {
hdr->frame_control |= morefrags;
/*
* No multi-rate retries for fragmented frames, that
* would completely throw off the NAV at other STAs.
*/
info->control.rates[1].idx = -1;
info->control.rates[2].idx = -1;
info->control.rates[3].idx = -1;
info->control.rates[4].idx = -1;
BUILD_BUG_ON(IEEE80211_TX_MAX_RATES != 5);
info->flags &= ~IEEE80211_TX_CTL_RATE_CTRL_PROBE;
} else {
hdr->frame_control &= ~morefrags;
next_len = 0;
}
hdr->seq_ctrl |= cpu_to_le16(fragnum & IEEE80211_SCTL_FRAG);
fragnum++;
}
return TX_CONTINUE;
}
static ieee80211_tx_result debug_noinline
ieee80211_tx_h_stats(struct ieee80211_tx_data *tx)
{
struct sk_buff *skb;
if (!tx->sta)
return TX_CONTINUE;
tx->sta->tx_packets++;
skb_queue_walk(&tx->skbs, skb) {
tx->sta->tx_fragments++;
tx->sta->tx_bytes += skb->len;
}
return TX_CONTINUE;
}
static ieee80211_tx_result debug_noinline
ieee80211_tx_h_encrypt(struct ieee80211_tx_data *tx)
{
if (!tx->key)
return TX_CONTINUE;
switch (tx->key->conf.cipher) {
case WLAN_CIPHER_SUITE_WEP40:
case WLAN_CIPHER_SUITE_WEP104:
return ieee80211_crypto_wep_encrypt(tx);
case WLAN_CIPHER_SUITE_TKIP:
return ieee80211_crypto_tkip_encrypt(tx);
case WLAN_CIPHER_SUITE_CCMP:
return ieee80211_crypto_ccmp_encrypt(tx);
case WLAN_CIPHER_SUITE_AES_CMAC:
return ieee80211_crypto_aes_cmac_encrypt(tx);
default:
return ieee80211_crypto_hw_encrypt(tx);
}
return TX_DROP;
}
static ieee80211_tx_result debug_noinline
ieee80211_tx_h_calculate_duration(struct ieee80211_tx_data *tx)
{
struct sk_buff *skb;
struct ieee80211_hdr *hdr;
int next_len;
bool group_addr;
skb_queue_walk(&tx->skbs, skb) {
hdr = (void *) skb->data;
if (unlikely(ieee80211_is_pspoll(hdr->frame_control)))
break; /* must not overwrite AID */
if (!skb_queue_is_last(&tx->skbs, skb)) {
struct sk_buff *next = skb_queue_next(&tx->skbs, skb);
next_len = next->len;
} else
next_len = 0;
group_addr = is_multicast_ether_addr(hdr->addr1);
hdr->duration_id =
ieee80211_duration(tx, skb, group_addr, next_len);
}
return TX_CONTINUE;
}
/* actual transmit path */
static bool ieee80211_tx_prep_agg(struct ieee80211_tx_data *tx,
struct sk_buff *skb,
struct ieee80211_tx_info *info,
struct tid_ampdu_tx *tid_tx,
int tid)
{
bool queued = false;
bool reset_agg_timer = false;
struct sk_buff *purge_skb = NULL;
if (test_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state)) {
info->flags |= IEEE80211_TX_CTL_AMPDU;
reset_agg_timer = true;
} else if (test_bit(HT_AGG_STATE_WANT_START, &tid_tx->state)) {
/*
* nothing -- this aggregation session is being started
* but that might still fail with the driver
*/
} else {
spin_lock(&tx->sta->lock);
/*
* Need to re-check now, because we may get here
*
* 1) in the window during which the setup is actually
* already done, but not marked yet because not all
* packets are spliced over to the driver pending
* queue yet -- if this happened we acquire the lock
* either before or after the splice happens, but
* need to recheck which of these cases happened.
*
* 2) during session teardown, if the OPERATIONAL bit
* was cleared due to the teardown but the pointer
* hasn't been assigned NULL yet (or we loaded it
* before it was assigned) -- in this case it may
* now be NULL which means we should just let the
* packet pass through because splicing the frames
* back is already done.
*/
tid_tx = rcu_dereference_protected_tid_tx(tx->sta, tid);
if (!tid_tx) {
/* do nothing, let packet pass through */
} else if (test_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state)) {
info->flags |= IEEE80211_TX_CTL_AMPDU;
reset_agg_timer = true;
} else {
queued = true;
info->control.vif = &tx->sdata->vif;
info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
__skb_queue_tail(&tid_tx->pending, skb);
if (skb_queue_len(&tid_tx->pending) > STA_MAX_TX_BUFFER)
purge_skb = __skb_dequeue(&tid_tx->pending);
}
spin_unlock(&tx->sta->lock);
if (purge_skb)
dev_kfree_skb(purge_skb);
}
/* reset session timer */
if (reset_agg_timer && tid_tx->timeout)
tid_tx->last_tx = jiffies;
return queued;
}
/*
* initialises @tx
*/
static ieee80211_tx_result
ieee80211_tx_prepare(struct ieee80211_sub_if_data *sdata,
struct ieee80211_tx_data *tx,
struct sk_buff *skb)
{
struct ieee80211_local *local = sdata->local;
struct ieee80211_hdr *hdr;
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
int tid;
u8 *qc;
memset(tx, 0, sizeof(*tx));
tx->skb = skb;
tx->local = local;
tx->sdata = sdata;
tx->channel = local->hw.conf.channel;
__skb_queue_head_init(&tx->skbs);
/*
* If this flag is set to true anywhere, and we get here,
* we are doing the needed processing, so remove the flag
* now.
*/
info->flags &= ~IEEE80211_TX_INTFL_NEED_TXPROCESSING;
hdr = (struct ieee80211_hdr *) skb->data;
if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
tx->sta = rcu_dereference(sdata->u.vlan.sta);
if (!tx->sta && sdata->dev->ieee80211_ptr->use_4addr)
return TX_DROP;
} else if (info->flags & IEEE80211_TX_CTL_INJECTED ||
tx->sdata->control_port_protocol == tx->skb->protocol) {
tx->sta = sta_info_get_bss(sdata, hdr->addr1);
}
if (!tx->sta)
tx->sta = sta_info_get(sdata, hdr->addr1);
if (tx->sta && ieee80211_is_data_qos(hdr->frame_control) &&
!ieee80211_is_qos_nullfunc(hdr->frame_control) &&
(local->hw.flags & IEEE80211_HW_AMPDU_AGGREGATION) &&
!(local->hw.flags & IEEE80211_HW_TX_AMPDU_SETUP_IN_HW)) {
struct tid_ampdu_tx *tid_tx;
qc = ieee80211_get_qos_ctl(hdr);
tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
tid_tx = rcu_dereference(tx->sta->ampdu_mlme.tid_tx[tid]);
if (tid_tx) {
bool queued;
queued = ieee80211_tx_prep_agg(tx, skb, info,
tid_tx, tid);
if (unlikely(queued))
return TX_QUEUED;
}
}
if (is_multicast_ether_addr(hdr->addr1)) {
tx->flags &= ~IEEE80211_TX_UNICAST;
info->flags |= IEEE80211_TX_CTL_NO_ACK;
} else
tx->flags |= IEEE80211_TX_UNICAST;
if (!(info->flags & IEEE80211_TX_CTL_DONTFRAG)) {
if (!(tx->flags & IEEE80211_TX_UNICAST) ||
skb->len + FCS_LEN <= local->hw.wiphy->frag_threshold ||
info->flags & IEEE80211_TX_CTL_AMPDU)
info->flags |= IEEE80211_TX_CTL_DONTFRAG;
}
if (!tx->sta)
info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT;
else if (test_and_clear_sta_flag(tx->sta, WLAN_STA_CLEAR_PS_FILT))
info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT;
info->flags |= IEEE80211_TX_CTL_FIRST_FRAGMENT;
return TX_CONTINUE;
}
static bool ieee80211_tx_frags(struct ieee80211_local *local,
struct ieee80211_vif *vif,
struct ieee80211_sta *sta,
struct sk_buff_head *skbs,
bool txpending)
{
struct sk_buff *skb, *tmp;
unsigned long flags;
skb_queue_walk_safe(skbs, skb, tmp) {
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
int q = info->hw_queue;
#ifdef CONFIG_MAC80211_VERBOSE_DEBUG
if (WARN_ON_ONCE(q >= local->hw.queues)) {
__skb_unlink(skb, skbs);
dev_kfree_skb(skb);
continue;
}
#endif
spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
if (local->queue_stop_reasons[q] ||
(!txpending && !skb_queue_empty(&local->pending[q]))) {
/*
* Since queue is stopped, queue up frames for later
* transmission from the tx-pending tasklet when the
* queue is woken again.
*/
if (txpending)
skb_queue_splice_init(skbs, &local->pending[q]);
else
skb_queue_splice_tail_init(skbs,
&local->pending[q]);
spin_unlock_irqrestore(&local->queue_stop_reason_lock,
flags);
return false;
}
spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
info->control.vif = vif;
info->control.sta = sta;
__skb_unlink(skb, skbs);
drv_tx(local, skb);
}
return true;
}
/*
* Returns false if the frame couldn't be transmitted but was queued instead.
*/
static bool __ieee80211_tx(struct ieee80211_local *local,
struct sk_buff_head *skbs, int led_len,
struct sta_info *sta, bool txpending)
{
struct ieee80211_tx_info *info;
struct ieee80211_sub_if_data *sdata;
struct ieee80211_vif *vif;
struct ieee80211_sta *pubsta;
struct sk_buff *skb;
bool result = true;
__le16 fc;
if (WARN_ON(skb_queue_empty(skbs)))
return true;
skb = skb_peek(skbs);
fc = ((struct ieee80211_hdr *)skb->data)->frame_control;
info = IEEE80211_SKB_CB(skb);
sdata = vif_to_sdata(info->control.vif);
if (sta && !sta->uploaded)
sta = NULL;
if (sta)
pubsta = &sta->sta;
else
pubsta = NULL;
switch (sdata->vif.type) {
case NL80211_IFTYPE_MONITOR:
sdata = rcu_dereference(local->monitor_sdata);
if (sdata) {
vif = &sdata->vif;
info->hw_queue =
vif->hw_queue[skb_get_queue_mapping(skb)];
} else if (local->hw.flags & IEEE80211_HW_QUEUE_CONTROL) {
dev_kfree_skb(skb);
return true;
} else
vif = NULL;
break;
case NL80211_IFTYPE_AP_VLAN:
sdata = container_of(sdata->bss,
struct ieee80211_sub_if_data, u.ap);
/* fall through */
default:
vif = &sdata->vif;
break;
}
if (local->ops->tx_frags)
drv_tx_frags(local, vif, pubsta, skbs);
else
result = ieee80211_tx_frags(local, vif, pubsta, skbs,
txpending);
ieee80211_tpt_led_trig_tx(local, fc, led_len);
ieee80211_led_tx(local, 1);
WARN_ON_ONCE(!skb_queue_empty(skbs));
return result;
}
/*
* Invoke TX handlers, return 0 on success and non-zero if the
* frame was dropped or queued.
*/
static int invoke_tx_handlers(struct ieee80211_tx_data *tx)
{
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
ieee80211_tx_result res = TX_DROP;
#define CALL_TXH(txh) \
do { \
res = txh(tx); \
if (res != TX_CONTINUE) \
goto txh_done; \
} while (0)
CALL_TXH(ieee80211_tx_h_dynamic_ps);
CALL_TXH(ieee80211_tx_h_check_assoc);
CALL_TXH(ieee80211_tx_h_ps_buf);
CALL_TXH(ieee80211_tx_h_check_control_port_protocol);
CALL_TXH(ieee80211_tx_h_select_key);
if (!(tx->local->hw.flags & IEEE80211_HW_HAS_RATE_CONTROL))
CALL_TXH(ieee80211_tx_h_rate_ctrl);
if (unlikely(info->flags & IEEE80211_TX_INTFL_RETRANSMISSION)) {
__skb_queue_tail(&tx->skbs, tx->skb);
tx->skb = NULL;
goto txh_done;
}
CALL_TXH(ieee80211_tx_h_michael_mic_add);
CALL_TXH(ieee80211_tx_h_sequence);
CALL_TXH(ieee80211_tx_h_fragment);
/* handlers after fragment must be aware of tx info fragmentation! */
CALL_TXH(ieee80211_tx_h_stats);
CALL_TXH(ieee80211_tx_h_encrypt);
if (!(tx->local->hw.flags & IEEE80211_HW_HAS_RATE_CONTROL))
CALL_TXH(ieee80211_tx_h_calculate_duration);
#undef CALL_TXH
txh_done:
if (unlikely(res == TX_DROP)) {
I802_DEBUG_INC(tx->local->tx_handlers_drop);
if (tx->skb)
dev_kfree_skb(tx->skb);
else
__skb_queue_purge(&tx->skbs);
return -1;
} else if (unlikely(res == TX_QUEUED)) {
I802_DEBUG_INC(tx->local->tx_handlers_queued);
return -1;
}
return 0;
}
/*
* Returns false if the frame couldn't be transmitted but was queued instead.
*/
static bool ieee80211_tx(struct ieee80211_sub_if_data *sdata,
struct sk_buff *skb, bool txpending)
{
struct ieee80211_local *local = sdata->local;
struct ieee80211_tx_data tx;
ieee80211_tx_result res_prepare;
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
bool result = true;
int led_len;
if (unlikely(skb->len < 10)) {
dev_kfree_skb(skb);
return true;
}
rcu_read_lock();
/* initialises tx */
led_len = skb->len;
res_prepare = ieee80211_tx_prepare(sdata, &tx, skb);
if (unlikely(res_prepare == TX_DROP)) {
dev_kfree_skb(skb);
goto out;
} else if (unlikely(res_prepare == TX_QUEUED)) {
goto out;
}
tx.channel = local->hw.conf.channel;
info->band = tx.channel->band;
/* set up hw_queue value early */
if (!(info->flags & IEEE80211_TX_CTL_TX_OFFCHAN) ||
!(local->hw.flags & IEEE80211_HW_QUEUE_CONTROL))
info->hw_queue =
sdata->vif.hw_queue[skb_get_queue_mapping(skb)];
if (!invoke_tx_handlers(&tx))
result = __ieee80211_tx(local, &tx.skbs, led_len,
tx.sta, txpending);
out:
rcu_read_unlock();
return result;
}
/* device xmit handlers */
static int ieee80211_skb_resize(struct ieee80211_sub_if_data *sdata,
struct sk_buff *skb,
int head_need, bool may_encrypt)
{
struct ieee80211_local *local = sdata->local;
int tail_need = 0;
if (may_encrypt && sdata->crypto_tx_tailroom_needed_cnt) {
tail_need = IEEE80211_ENCRYPT_TAILROOM;
tail_need -= skb_tailroom(skb);
tail_need = max_t(int, tail_need, 0);
}
if (skb_cloned(skb))
I802_DEBUG_INC(local->tx_expand_skb_head_cloned);
else if (head_need || tail_need)
I802_DEBUG_INC(local->tx_expand_skb_head);
else
return 0;
if (pskb_expand_head(skb, head_need, tail_need, GFP_ATOMIC)) {
wiphy_debug(local->hw.wiphy,
"failed to reallocate TX buffer\n");
return -ENOMEM;
}
return 0;
}
void ieee80211_xmit(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb)
{
struct ieee80211_local *local = sdata->local;
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
int headroom;
bool may_encrypt;
rcu_read_lock();
may_encrypt = !(info->flags & IEEE80211_TX_INTFL_DONT_ENCRYPT);
headroom = local->tx_headroom;
if (may_encrypt)
headroom += IEEE80211_ENCRYPT_HEADROOM;
headroom -= skb_headroom(skb);
headroom = max_t(int, 0, headroom);
if (ieee80211_skb_resize(sdata, skb, headroom, may_encrypt)) {
dev_kfree_skb(skb);
rcu_read_unlock();
return;
}
hdr = (struct ieee80211_hdr *) skb->data;
info->control.vif = &sdata->vif;
if (ieee80211_vif_is_mesh(&sdata->vif) &&
ieee80211_is_data(hdr->frame_control) &&
!is_multicast_ether_addr(hdr->addr1) &&
mesh_nexthop_resolve(skb, sdata)) {
/* skb queued: don't free */
rcu_read_unlock();
return;
}
ieee80211_set_qos_hdr(sdata, skb);
ieee80211_tx(sdata, skb, false);
rcu_read_unlock();
}
static bool ieee80211_parse_tx_radiotap(struct sk_buff *skb)
{
struct ieee80211_radiotap_iterator iterator;
struct ieee80211_radiotap_header *rthdr =
(struct ieee80211_radiotap_header *) skb->data;
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
int ret = ieee80211_radiotap_iterator_init(&iterator, rthdr, skb->len,
NULL);
u16 txflags;
info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT |
IEEE80211_TX_CTL_DONTFRAG;
/*
* for every radiotap entry that is present
* (ieee80211_radiotap_iterator_next returns -ENOENT when no more
* entries present, or -EINVAL on error)
*/
while (!ret) {
ret = ieee80211_radiotap_iterator_next(&iterator);
if (ret)
continue;
/* see if this argument is something we can use */
switch (iterator.this_arg_index) {
/*
* You must take care when dereferencing iterator.this_arg
* for multibyte types... the pointer is not aligned. Use
* get_unaligned((type *)iterator.this_arg) to dereference
* iterator.this_arg for type "type" safely on all arches.
*/
case IEEE80211_RADIOTAP_FLAGS:
if (*iterator.this_arg & IEEE80211_RADIOTAP_F_FCS) {
/*
* this indicates that the skb we have been
* handed has the 32-bit FCS CRC at the end...
* we should react to that by snipping it off
* because it will be recomputed and added
* on transmission
*/
if (skb->len < (iterator._max_length + FCS_LEN))
return false;
skb_trim(skb, skb->len - FCS_LEN);
}
if (*iterator.this_arg & IEEE80211_RADIOTAP_F_WEP)
info->flags &= ~IEEE80211_TX_INTFL_DONT_ENCRYPT;
if (*iterator.this_arg & IEEE80211_RADIOTAP_F_FRAG)
info->flags &= ~IEEE80211_TX_CTL_DONTFRAG;
break;
case IEEE80211_RADIOTAP_TX_FLAGS:
txflags = get_unaligned_le16(iterator.this_arg);
if (txflags & IEEE80211_RADIOTAP_F_TX_NOACK)
info->flags |= IEEE80211_TX_CTL_NO_ACK;
break;
/*
* Please update the file
* Documentation/networking/mac80211-injection.txt
* when parsing new fields here.
*/
default:
break;
}
}
if (ret != -ENOENT) /* ie, if we didn't simply run out of fields */
return false;
/*
* remove the radiotap header
* iterator->_max_length was sanity-checked against
* skb->len by iterator init
*/
skb_pull(skb, iterator._max_length);
return true;
}
netdev_tx_t ieee80211_monitor_start_xmit(struct sk_buff *skb,
struct net_device *dev)
{
struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
struct ieee80211_channel *chan = local->hw.conf.channel;
struct ieee80211_radiotap_header *prthdr =
(struct ieee80211_radiotap_header *)skb->data;
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
struct ieee80211_hdr *hdr;
struct ieee80211_sub_if_data *tmp_sdata, *sdata;
u16 len_rthdr;
int hdrlen;
/*
* Frame injection is not allowed if beaconing is not allowed
* or if we need radar detection. Beaconing is usually not allowed when
* the mode or operation (Adhoc, AP, Mesh) does not support DFS.
* Passive scan is also used in world regulatory domains where
* your country is not known and as such it should be treated as
* NO TX unless the channel is explicitly allowed in which case
* your current regulatory domain would not have the passive scan
* flag.
*
* Since AP mode uses monitor interfaces to inject/TX management
* frames we can make AP mode the exception to this rule once it
* supports radar detection as its implementation can deal with
* radar detection by itself. We can do that later by adding a
* monitor flag interfaces used for AP support.
*/
if ((chan->flags & (IEEE80211_CHAN_NO_IBSS | IEEE80211_CHAN_RADAR |
IEEE80211_CHAN_PASSIVE_SCAN)))
goto fail;
/* check for not even having the fixed radiotap header part */
if (unlikely(skb->len < sizeof(struct ieee80211_radiotap_header)))
goto fail; /* too short to be possibly valid */
/* is it a header version we can trust to find length from? */
if (unlikely(prthdr->it_version))
goto fail; /* only version 0 is supported */
/* then there must be a radiotap header with a length we can use */
len_rthdr = ieee80211_get_radiotap_len(skb->data);
/* does the skb contain enough to deliver on the alleged length? */
if (unlikely(skb->len < len_rthdr))
goto fail; /* skb too short for claimed rt header extent */
/*
* fix up the pointers accounting for the radiotap
* header still being in there. We are being given
* a precooked IEEE80211 header so no need for
* normal processing
*/
skb_set_mac_header(skb, len_rthdr);
/*
* these are just fixed to the end of the rt area since we
* don't have any better information and at this point, nobody cares
*/
skb_set_network_header(skb, len_rthdr);
skb_set_transport_header(skb, len_rthdr);
if (skb->len < len_rthdr + 2)
goto fail;
hdr = (struct ieee80211_hdr *)(skb->data + len_rthdr);
hdrlen = ieee80211_hdrlen(hdr->frame_control);
if (skb->len < len_rthdr + hdrlen)
goto fail;
/*
* Initialize skb->protocol if the injected frame is a data frame
* carrying a rfc1042 header
*/
if (ieee80211_is_data(hdr->frame_control) &&
skb->len >= len_rthdr + hdrlen + sizeof(rfc1042_header) + 2) {
u8 *payload = (u8 *)hdr + hdrlen;
if (ether_addr_equal(payload, rfc1042_header))
skb->protocol = cpu_to_be16((payload[6] << 8) |
payload[7]);
}
memset(info, 0, sizeof(*info));
info->flags = IEEE80211_TX_CTL_REQ_TX_STATUS |
IEEE80211_TX_CTL_INJECTED;
/* process and remove the injection radiotap header */
if (!ieee80211_parse_tx_radiotap(skb))
goto fail;
rcu_read_lock();
/*
* We process outgoing injected frames that have a local address
* we handle as though they are non-injected frames.
* This code here isn't entirely correct, the local MAC address
* isn't always enough to find the interface to use; for proper
* VLAN/WDS support we will need a different mechanism (which
* likely isn't going to be monitor interfaces).
*/
sdata = IEEE80211_DEV_TO_SUB_IF(dev);
list_for_each_entry_rcu(tmp_sdata, &local->interfaces, list) {
if (!ieee80211_sdata_running(tmp_sdata))
continue;
if (tmp_sdata->vif.type == NL80211_IFTYPE_MONITOR ||
tmp_sdata->vif.type == NL80211_IFTYPE_AP_VLAN ||
tmp_sdata->vif.type == NL80211_IFTYPE_WDS)
continue;
if (ether_addr_equal(tmp_sdata->vif.addr, hdr->addr2)) {
sdata = tmp_sdata;
break;
}
}
ieee80211_xmit(sdata, skb);
rcu_read_unlock();
return NETDEV_TX_OK;
fail:
dev_kfree_skb(skb);
return NETDEV_TX_OK; /* meaning, we dealt with the skb */
}
/**
* ieee80211_subif_start_xmit - netif start_xmit function for Ethernet-type
* subinterfaces (wlan#, WDS, and VLAN interfaces)
* @skb: packet to be sent
* @dev: incoming interface
*
* Returns: 0 on success (and frees skb in this case) or 1 on failure (skb will
* not be freed, and caller is responsible for either retrying later or freeing
* skb).
*
* This function takes in an Ethernet header and encapsulates it with suitable
* IEEE 802.11 header based on which interface the packet is coming in. The
* encapsulated packet will then be passed to master interface, wlan#.11, for
* transmission (through low-level driver).
*/
netdev_tx_t ieee80211_subif_start_xmit(struct sk_buff *skb,
struct net_device *dev)
{
struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
struct ieee80211_local *local = sdata->local;
struct ieee80211_tx_info *info;
int ret = NETDEV_TX_BUSY, head_need;
u16 ethertype, hdrlen, meshhdrlen = 0;
__le16 fc;
struct ieee80211_hdr hdr;
struct ieee80211s_hdr mesh_hdr __maybe_unused;
struct mesh_path __maybe_unused *mppath = NULL, *mpath = NULL;
const u8 *encaps_data;
int encaps_len, skip_header_bytes;
int nh_pos, h_pos;
struct sta_info *sta = NULL;
bool wme_sta = false, authorized = false, tdls_auth = false;
bool tdls_direct = false;
bool multicast;
u32 info_flags = 0;
u16 info_id = 0;
if (unlikely(skb->len < ETH_HLEN)) {
ret = NETDEV_TX_OK;
goto fail;
}
/* convert Ethernet header to proper 802.11 header (based on
* operation mode) */
ethertype = (skb->data[12] << 8) | skb->data[13];
fc = cpu_to_le16(IEEE80211_FTYPE_DATA | IEEE80211_STYPE_DATA);
switch (sdata->vif.type) {
case NL80211_IFTYPE_AP_VLAN:
rcu_read_lock();
sta = rcu_dereference(sdata->u.vlan.sta);
if (sta) {
fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS);
/* RA TA DA SA */
memcpy(hdr.addr1, sta->sta.addr, ETH_ALEN);
memcpy(hdr.addr2, sdata->vif.addr, ETH_ALEN);
memcpy(hdr.addr3, skb->data, ETH_ALEN);
memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN);
hdrlen = 30;
authorized = test_sta_flag(sta, WLAN_STA_AUTHORIZED);
wme_sta = test_sta_flag(sta, WLAN_STA_WME);
}
rcu_read_unlock();
if (sta)
break;
/* fall through */
case NL80211_IFTYPE_AP:
fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS);
/* DA BSSID SA */
memcpy(hdr.addr1, skb->data, ETH_ALEN);
memcpy(hdr.addr2, sdata->vif.addr, ETH_ALEN);
memcpy(hdr.addr3, skb->data + ETH_ALEN, ETH_ALEN);
hdrlen = 24;
break;
case NL80211_IFTYPE_WDS:
fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS);
/* RA TA DA SA */
memcpy(hdr.addr1, sdata->u.wds.remote_addr, ETH_ALEN);
memcpy(hdr.addr2, sdata->vif.addr, ETH_ALEN);
memcpy(hdr.addr3, skb->data, ETH_ALEN);
memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN);
hdrlen = 30;
break;
#ifdef CONFIG_MAC80211_MESH
case NL80211_IFTYPE_MESH_POINT:
if (!sdata->u.mesh.mshcfg.dot11MeshTTL) {
/* Do not send frames with mesh_ttl == 0 */
sdata->u.mesh.mshstats.dropped_frames_ttl++;
ret = NETDEV_TX_OK;
goto fail;
}
rcu_read_lock();
if (!is_multicast_ether_addr(skb->data)) {
mpath = mesh_path_lookup(skb->data, sdata);
if (!mpath)
mppath = mpp_path_lookup(skb->data, sdata);
}
/*
* Use address extension if it is a packet from
* another interface or if we know the destination
* is being proxied by a portal (i.e. portal address
* differs from proxied address)
*/
if (ether_addr_equal(sdata->vif.addr, skb->data + ETH_ALEN) &&
!(mppath && !ether_addr_equal(mppath->mpp, skb->data))) {
hdrlen = ieee80211_fill_mesh_addresses(&hdr, &fc,
skb->data, skb->data + ETH_ALEN);
rcu_read_unlock();
meshhdrlen = ieee80211_new_mesh_header(&mesh_hdr,
sdata, NULL, NULL);
} else {
int is_mesh_mcast = 1;
const u8 *mesh_da;
if (is_multicast_ether_addr(skb->data))
/* DA TA mSA AE:SA */
mesh_da = skb->data;
else {
static const u8 bcast[ETH_ALEN] =
{ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
if (mppath) {
/* RA TA mDA mSA AE:DA SA */
mesh_da = mppath->mpp;
is_mesh_mcast = 0;
} else {
/* DA TA mSA AE:SA */
mesh_da = bcast;
}
}
hdrlen = ieee80211_fill_mesh_addresses(&hdr, &fc,
mesh_da, sdata->vif.addr);
rcu_read_unlock();
if (is_mesh_mcast)
meshhdrlen =
ieee80211_new_mesh_header(&mesh_hdr,
sdata,
skb->data + ETH_ALEN,
NULL);
else
meshhdrlen =
ieee80211_new_mesh_header(&mesh_hdr,
sdata,
skb->data,
skb->data + ETH_ALEN);
}
break;
#endif
case NL80211_IFTYPE_STATION:
if (sdata->wdev.wiphy->flags & WIPHY_FLAG_SUPPORTS_TDLS) {
bool tdls_peer = false;
rcu_read_lock();
sta = sta_info_get(sdata, skb->data);
if (sta) {
authorized = test_sta_flag(sta,
WLAN_STA_AUTHORIZED);
wme_sta = test_sta_flag(sta, WLAN_STA_WME);
tdls_peer = test_sta_flag(sta,
WLAN_STA_TDLS_PEER);
tdls_auth = test_sta_flag(sta,
WLAN_STA_TDLS_PEER_AUTH);
}
rcu_read_unlock();
/*
* If the TDLS link is enabled, send everything
* directly. Otherwise, allow TDLS setup frames
* to be transmitted indirectly.
*/
tdls_direct = tdls_peer && (tdls_auth ||
!(ethertype == ETH_P_TDLS && skb->len > 14 &&
skb->data[14] == WLAN_TDLS_SNAP_RFTYPE));
}
if (tdls_direct) {
/* link during setup - throw out frames to peer */
if (!tdls_auth) {
ret = NETDEV_TX_OK;
goto fail;
}
/* DA SA BSSID */
memcpy(hdr.addr1, skb->data, ETH_ALEN);
memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
memcpy(hdr.addr3, sdata->u.mgd.bssid, ETH_ALEN);
hdrlen = 24;
} else if (sdata->u.mgd.use_4addr &&
cpu_to_be16(ethertype) != sdata->control_port_protocol) {
fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS |
IEEE80211_FCTL_TODS);
/* RA TA DA SA */
memcpy(hdr.addr1, sdata->u.mgd.bssid, ETH_ALEN);
memcpy(hdr.addr2, sdata->vif.addr, ETH_ALEN);
memcpy(hdr.addr3, skb->data, ETH_ALEN);
memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN);
hdrlen = 30;
} else {
fc |= cpu_to_le16(IEEE80211_FCTL_TODS);
/* BSSID SA DA */
memcpy(hdr.addr1, sdata->u.mgd.bssid, ETH_ALEN);
memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
memcpy(hdr.addr3, skb->data, ETH_ALEN);
hdrlen = 24;
}
break;
case NL80211_IFTYPE_ADHOC:
/* DA SA BSSID */
memcpy(hdr.addr1, skb->data, ETH_ALEN);
memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
memcpy(hdr.addr3, sdata->u.ibss.bssid, ETH_ALEN);
hdrlen = 24;
break;
default:
ret = NETDEV_TX_OK;
goto fail;
}
/*
* There's no need to try to look up the destination
* if it is a multicast address (which can only happen
* in AP mode)
*/
multicast = is_multicast_ether_addr(hdr.addr1);
if (!multicast) {
rcu_read_lock();
sta = sta_info_get(sdata, hdr.addr1);
if (sta) {
authorized = test_sta_flag(sta, WLAN_STA_AUTHORIZED);
wme_sta = test_sta_flag(sta, WLAN_STA_WME);
}
rcu_read_unlock();
}
/* For mesh, the use of the QoS header is mandatory */
if (ieee80211_vif_is_mesh(&sdata->vif))
wme_sta = true;
/* receiver and we are QoS enabled, use a QoS type frame */
if (wme_sta && local->hw.queues >= IEEE80211_NUM_ACS) {
fc |= cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
hdrlen += 2;
}
/*
* Drop unicast frames to unauthorised stations unless they are
* EAPOL frames from the local station.
*/
if (unlikely(!ieee80211_vif_is_mesh(&sdata->vif) &&
!is_multicast_ether_addr(hdr.addr1) && !authorized &&
(cpu_to_be16(ethertype) != sdata->control_port_protocol ||
!ether_addr_equal(sdata->vif.addr, skb->data + ETH_ALEN)))) {
#ifdef CONFIG_MAC80211_VERBOSE_DEBUG
net_info_ratelimited("%s: dropped frame to %pM (unauthorized port)\n",
dev->name, hdr.addr1);
#endif
I802_DEBUG_INC(local->tx_handlers_drop_unauth_port);
ret = NETDEV_TX_OK;
goto fail;
}
if (unlikely(!multicast && skb->sk &&
skb_shinfo(skb)->tx_flags & SKBTX_WIFI_STATUS)) {
struct sk_buff *orig_skb = skb;
skb = skb_clone(skb, GFP_ATOMIC);
if (skb) {
unsigned long flags;
int id, r;
spin_lock_irqsave(&local->ack_status_lock, flags);
r = idr_get_new_above(&local->ack_status_frames,
orig_skb, 1, &id);
if (r == -EAGAIN) {
idr_pre_get(&local->ack_status_frames,
GFP_ATOMIC);
r = idr_get_new_above(&local->ack_status_frames,
orig_skb, 1, &id);
}
if (WARN_ON(!id) || id > 0xffff) {
idr_remove(&local->ack_status_frames, id);
r = -ERANGE;
}
spin_unlock_irqrestore(&local->ack_status_lock, flags);
if (!r) {
info_id = id;
info_flags |= IEEE80211_TX_CTL_REQ_TX_STATUS;
} else if (skb_shared(skb)) {
kfree_skb(orig_skb);
} else {
kfree_skb(skb);
skb = orig_skb;
}
} else {
/* couldn't clone -- lose tx status ... */
skb = orig_skb;
}
}
/*
* If the skb is shared we need to obtain our own copy.
*/
if (skb_shared(skb)) {
struct sk_buff *tmp_skb = skb;
/* can't happen -- skb is a clone if info_id != 0 */
WARN_ON(info_id);
skb = skb_clone(skb, GFP_ATOMIC);
kfree_skb(tmp_skb);
if (!skb) {
ret = NETDEV_TX_OK;
goto fail;
}
}
hdr.frame_control = fc;
hdr.duration_id = 0;
hdr.seq_ctrl = 0;
skip_header_bytes = ETH_HLEN;
if (ethertype == ETH_P_AARP || ethertype == ETH_P_IPX) {
encaps_data = bridge_tunnel_header;
encaps_len = sizeof(bridge_tunnel_header);
skip_header_bytes -= 2;
} else if (ethertype >= 0x600) {
encaps_data = rfc1042_header;
encaps_len = sizeof(rfc1042_header);
skip_header_bytes -= 2;
} else {
encaps_data = NULL;
encaps_len = 0;
}
nh_pos = skb_network_header(skb) - skb->data;
h_pos = skb_transport_header(skb) - skb->data;
skb_pull(skb, skip_header_bytes);
nh_pos -= skip_header_bytes;
h_pos -= skip_header_bytes;
head_need = hdrlen + encaps_len + meshhdrlen - skb_headroom(skb);
/*
* So we need to modify the skb header and hence need a copy of
* that. The head_need variable above doesn't, so far, include
* the needed header space that we don't need right away. If we
* can, then we don't reallocate right now but only after the
* frame arrives at the master device (if it does...)
*
* If we cannot, however, then we will reallocate to include all
* the ever needed space. Also, if we need to reallocate it anyway,
* make it big enough for everything we may ever need.
*/
if (head_need > 0 || skb_cloned(skb)) {
head_need += IEEE80211_ENCRYPT_HEADROOM;
head_need += local->tx_headroom;
head_need = max_t(int, 0, head_need);
if (ieee80211_skb_resize(sdata, skb, head_need, true))
goto fail;
}
if (encaps_data) {
memcpy(skb_push(skb, encaps_len), encaps_data, encaps_len);
nh_pos += encaps_len;
h_pos += encaps_len;
}
#ifdef CONFIG_MAC80211_MESH
if (meshhdrlen > 0) {
memcpy(skb_push(skb, meshhdrlen), &mesh_hdr, meshhdrlen);
nh_pos += meshhdrlen;
h_pos += meshhdrlen;
}
#endif
if (ieee80211_is_data_qos(fc)) {
__le16 *qos_control;
qos_control = (__le16*) skb_push(skb, 2);
memcpy(skb_push(skb, hdrlen - 2), &hdr, hdrlen - 2);
/*
* Maybe we could actually set some fields here, for now just
* initialise to zero to indicate no special operation.
*/
*qos_control = 0;
} else
memcpy(skb_push(skb, hdrlen), &hdr, hdrlen);
nh_pos += hdrlen;
h_pos += hdrlen;
dev->stats.tx_packets++;
dev->stats.tx_bytes += skb->len;
/* Update skb pointers to various headers since this modified frame
* is going to go through Linux networking code that may potentially
* need things like pointer to IP header. */
skb_set_mac_header(skb, 0);
skb_set_network_header(skb, nh_pos);
skb_set_transport_header(skb, h_pos);
info = IEEE80211_SKB_CB(skb);
memset(info, 0, sizeof(*info));
dev->trans_start = jiffies;
info->flags = info_flags;
info->ack_frame_id = info_id;
ieee80211_xmit(sdata, skb);
return NETDEV_TX_OK;
fail:
if (ret == NETDEV_TX_OK)
dev_kfree_skb(skb);
return ret;
}
/*
* ieee80211_clear_tx_pending may not be called in a context where
* it is possible that it packets could come in again.
*/
void ieee80211_clear_tx_pending(struct ieee80211_local *local)
{
int i;
for (i = 0; i < local->hw.queues; i++)
skb_queue_purge(&local->pending[i]);
}
/*
* Returns false if the frame couldn't be transmitted but was queued instead,
* which in this case means re-queued -- take as an indication to stop sending
* more pending frames.
*/
static bool ieee80211_tx_pending_skb(struct ieee80211_local *local,
struct sk_buff *skb)
{
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
struct ieee80211_sub_if_data *sdata;
struct sta_info *sta;
struct ieee80211_hdr *hdr;
bool result;
sdata = vif_to_sdata(info->control.vif);
if (info->flags & IEEE80211_TX_INTFL_NEED_TXPROCESSING) {
result = ieee80211_tx(sdata, skb, true);
} else {
struct sk_buff_head skbs;
__skb_queue_head_init(&skbs);
__skb_queue_tail(&skbs, skb);
hdr = (struct ieee80211_hdr *)skb->data;
sta = sta_info_get(sdata, hdr->addr1);
result = __ieee80211_tx(local, &skbs, skb->len, sta, true);
}
return result;
}
/*
* Transmit all pending packets. Called from tasklet.
*/
void ieee80211_tx_pending(unsigned long data)
{
struct ieee80211_local *local = (struct ieee80211_local *)data;
unsigned long flags;
int i;
bool txok;
rcu_read_lock();
spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
for (i = 0; i < local->hw.queues; i++) {
/*
* If queue is stopped by something other than due to pending
* frames, or we have no pending frames, proceed to next queue.
*/
if (local->queue_stop_reasons[i] ||
skb_queue_empty(&local->pending[i]))
continue;
while (!skb_queue_empty(&local->pending[i])) {
struct sk_buff *skb = __skb_dequeue(&local->pending[i]);
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
if (WARN_ON(!info->control.vif)) {
kfree_skb(skb);
continue;
}
spin_unlock_irqrestore(&local->queue_stop_reason_lock,
flags);
txok = ieee80211_tx_pending_skb(local, skb);
spin_lock_irqsave(&local->queue_stop_reason_lock,
flags);
if (!txok)
break;
}
if (skb_queue_empty(&local->pending[i]))
ieee80211_propagate_queue_wake(local, i);
}
spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
rcu_read_unlock();
}
/* functions for drivers to get certain frames */
static void ieee80211_beacon_add_tim(struct ieee80211_sub_if_data *sdata,
struct ieee80211_if_ap *bss,
struct sk_buff *skb,
struct beacon_data *beacon)
{
u8 *pos, *tim;
int aid0 = 0;
int i, have_bits = 0, n1, n2;
/* Generate bitmap for TIM only if there are any STAs in power save
* mode. */
if (atomic_read(&bss->num_sta_ps) > 0)
/* in the hope that this is faster than
* checking byte-for-byte */
have_bits = !bitmap_empty((unsigned long*)bss->tim,
IEEE80211_MAX_AID+1);
if (bss->dtim_count == 0)
bss->dtim_count = sdata->vif.bss_conf.dtim_period - 1;
else
bss->dtim_count--;
tim = pos = (u8 *) skb_put(skb, 6);
*pos++ = WLAN_EID_TIM;
*pos++ = 4;
*pos++ = bss->dtim_count;
*pos++ = sdata->vif.bss_conf.dtim_period;
if (bss->dtim_count == 0 && !skb_queue_empty(&bss->ps_bc_buf))
aid0 = 1;
bss->dtim_bc_mc = aid0 == 1;
if (have_bits) {
/* Find largest even number N1 so that bits numbered 1 through
* (N1 x 8) - 1 in the bitmap are 0 and number N2 so that bits
* (N2 + 1) x 8 through 2007 are 0. */
n1 = 0;
for (i = 0; i < IEEE80211_MAX_TIM_LEN; i++) {
if (bss->tim[i]) {
n1 = i & 0xfe;
break;
}
}
n2 = n1;
for (i = IEEE80211_MAX_TIM_LEN - 1; i >= n1; i--) {
if (bss->tim[i]) {
n2 = i;
break;
}
}
/* Bitmap control */
*pos++ = n1 | aid0;
/* Part Virt Bitmap */
skb_put(skb, n2 - n1);
memcpy(pos, bss->tim + n1, n2 - n1 + 1);
tim[1] = n2 - n1 + 4;
} else {
*pos++ = aid0; /* Bitmap control */
*pos++ = 0; /* Part Virt Bitmap */
}
}
struct sk_buff *ieee80211_beacon_get_tim(struct ieee80211_hw *hw,
struct ieee80211_vif *vif,
u16 *tim_offset, u16 *tim_length)
{
struct ieee80211_local *local = hw_to_local(hw);
struct sk_buff *skb = NULL;
struct ieee80211_tx_info *info;
struct ieee80211_sub_if_data *sdata = NULL;
struct ieee80211_if_ap *ap = NULL;
struct beacon_data *beacon;
struct ieee80211_supported_band *sband;
enum ieee80211_band band = local->hw.conf.channel->band;
struct ieee80211_tx_rate_control txrc;
sband = local->hw.wiphy->bands[band];
rcu_read_lock();
sdata = vif_to_sdata(vif);
if (!ieee80211_sdata_running(sdata))
goto out;
if (tim_offset)
*tim_offset = 0;
if (tim_length)
*tim_length = 0;
if (sdata->vif.type == NL80211_IFTYPE_AP) {
ap = &sdata->u.ap;
beacon = rcu_dereference(ap->beacon);
if (beacon) {
/*
* headroom, head length,
* tail length and maximum TIM length
*/
skb = dev_alloc_skb(local->tx_headroom +
beacon->head_len +
beacon->tail_len + 256);
if (!skb)
goto out;
skb_reserve(skb, local->tx_headroom);
memcpy(skb_put(skb, beacon->head_len), beacon->head,
beacon->head_len);
/*
* Not very nice, but we want to allow the driver to call
* ieee80211_beacon_get() as a response to the set_tim()
* callback. That, however, is already invoked under the
* sta_lock to guarantee consistent and race-free update
* of the tim bitmap in mac80211 and the driver.
*/
if (local->tim_in_locked_section) {
ieee80211_beacon_add_tim(sdata, ap, skb,
beacon);
} else {
unsigned long flags;
spin_lock_irqsave(&local->tim_lock, flags);
ieee80211_beacon_add_tim(sdata, ap, skb,
beacon);
spin_unlock_irqrestore(&local->tim_lock, flags);
}
if (tim_offset)
*tim_offset = beacon->head_len;
if (tim_length)
*tim_length = skb->len - beacon->head_len;
if (beacon->tail)
memcpy(skb_put(skb, beacon->tail_len),
beacon->tail, beacon->tail_len);
} else
goto out;
} else if (sdata->vif.type == NL80211_IFTYPE_ADHOC) {
struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
struct ieee80211_hdr *hdr;
struct sk_buff *presp = rcu_dereference(ifibss->presp);
if (!presp)
goto out;
skb = skb_copy(presp, GFP_ATOMIC);
if (!skb)
goto out;
hdr = (struct ieee80211_hdr *) skb->data;
hdr->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
IEEE80211_STYPE_BEACON);
} else if (ieee80211_vif_is_mesh(&sdata->vif)) {
struct ieee80211_mgmt *mgmt;
struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
u8 *pos;
int hdr_len = offsetof(struct ieee80211_mgmt, u.beacon) +
sizeof(mgmt->u.beacon);
#ifdef CONFIG_MAC80211_MESH
if (!sdata->u.mesh.mesh_id_len)
goto out;
#endif
if (ifmsh->sync_ops)
ifmsh->sync_ops->adjust_tbtt(
sdata);
skb = dev_alloc_skb(local->tx_headroom +
hdr_len +
2 + /* NULL SSID */
2 + 8 + /* supported rates */
2 + 3 + /* DS params */
2 + (IEEE80211_MAX_SUPP_RATES - 8) +
2 + sizeof(struct ieee80211_ht_cap) +
2 + sizeof(struct ieee80211_ht_operation) +
2 + sdata->u.mesh.mesh_id_len +
2 + sizeof(struct ieee80211_meshconf_ie) +
sdata->u.mesh.ie_len);
if (!skb)
goto out;
skb_reserve(skb, local->hw.extra_tx_headroom);
mgmt = (struct ieee80211_mgmt *) skb_put(skb, hdr_len);
memset(mgmt, 0, hdr_len);
mgmt->frame_control =
cpu_to_le16(IEEE80211_FTYPE_MGMT | IEEE80211_STYPE_BEACON);
memset(mgmt->da, 0xff, ETH_ALEN);
memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
mgmt->u.beacon.beacon_int =
cpu_to_le16(sdata->vif.bss_conf.beacon_int);
mgmt->u.beacon.capab_info |= cpu_to_le16(
sdata->u.mesh.security ? WLAN_CAPABILITY_PRIVACY : 0);
pos = skb_put(skb, 2);
*pos++ = WLAN_EID_SSID;
*pos++ = 0x0;
if (ieee80211_add_srates_ie(sdata, skb, true) ||
mesh_add_ds_params_ie(skb, sdata) ||
ieee80211_add_ext_srates_ie(sdata, skb, true) ||
mesh_add_rsn_ie(skb, sdata) ||
mesh_add_ht_cap_ie(skb, sdata) ||
mesh_add_ht_oper_ie(skb, sdata) ||
mesh_add_meshid_ie(skb, sdata) ||
mesh_add_meshconf_ie(skb, sdata) ||
mesh_add_vendor_ies(skb, sdata)) {
pr_err("o11s: couldn't add ies!\n");
goto out;
}
} else {
WARN_ON(1);
goto out;
}
info = IEEE80211_SKB_CB(skb);
info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
info->flags |= IEEE80211_TX_CTL_NO_ACK;
info->band = band;
memset(&txrc, 0, sizeof(txrc));
txrc.hw = hw;
txrc.sband = sband;
txrc.bss_conf = &sdata->vif.bss_conf;
txrc.skb = skb;
txrc.reported_rate.idx = -1;
txrc.rate_idx_mask = sdata->rc_rateidx_mask[band];
if (txrc.rate_idx_mask == (1 << sband->n_bitrates) - 1)
txrc.max_rate_idx = -1;
else
txrc.max_rate_idx = fls(txrc.rate_idx_mask) - 1;
memcpy(txrc.rate_idx_mcs_mask, sdata->rc_rateidx_mcs_mask[band],
sizeof(txrc.rate_idx_mcs_mask));
txrc.bss = true;
rate_control_get_rate(sdata, NULL, &txrc);
info->control.vif = vif;
info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT |
IEEE80211_TX_CTL_ASSIGN_SEQ |
IEEE80211_TX_CTL_FIRST_FRAGMENT;
out:
rcu_read_unlock();
return skb;
}
EXPORT_SYMBOL(ieee80211_beacon_get_tim);
struct sk_buff *ieee80211_proberesp_get(struct ieee80211_hw *hw,
struct ieee80211_vif *vif)
{
struct ieee80211_if_ap *ap = NULL;
struct sk_buff *presp = NULL, *skb = NULL;
struct ieee80211_hdr *hdr;
struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
if (sdata->vif.type != NL80211_IFTYPE_AP)
return NULL;
rcu_read_lock();
ap = &sdata->u.ap;
presp = rcu_dereference(ap->probe_resp);
if (!presp)
goto out;
skb = skb_copy(presp, GFP_ATOMIC);
if (!skb)
goto out;
hdr = (struct ieee80211_hdr *) skb->data;
memset(hdr->addr1, 0, sizeof(hdr->addr1));
out:
rcu_read_unlock();
return skb;
}
EXPORT_SYMBOL(ieee80211_proberesp_get);
struct sk_buff *ieee80211_pspoll_get(struct ieee80211_hw *hw,
struct ieee80211_vif *vif)
{
struct ieee80211_sub_if_data *sdata;
struct ieee80211_if_managed *ifmgd;
struct ieee80211_pspoll *pspoll;
struct ieee80211_local *local;
struct sk_buff *skb;
if (WARN_ON(vif->type != NL80211_IFTYPE_STATION))
return NULL;
sdata = vif_to_sdata(vif);
ifmgd = &sdata->u.mgd;
local = sdata->local;
skb = dev_alloc_skb(local->hw.extra_tx_headroom + sizeof(*pspoll));
if (!skb)
return NULL;
skb_reserve(skb, local->hw.extra_tx_headroom);
pspoll = (struct ieee80211_pspoll *) skb_put(skb, sizeof(*pspoll));
memset(pspoll, 0, sizeof(*pspoll));
pspoll->frame_control = cpu_to_le16(IEEE80211_FTYPE_CTL |
IEEE80211_STYPE_PSPOLL);
pspoll->aid = cpu_to_le16(ifmgd->aid);
/* aid in PS-Poll has its two MSBs each set to 1 */
pspoll->aid |= cpu_to_le16(1 << 15 | 1 << 14);
memcpy(pspoll->bssid, ifmgd->bssid, ETH_ALEN);
memcpy(pspoll->ta, vif->addr, ETH_ALEN);
return skb;
}
EXPORT_SYMBOL(ieee80211_pspoll_get);
struct sk_buff *ieee80211_nullfunc_get(struct ieee80211_hw *hw,
struct ieee80211_vif *vif)
{
struct ieee80211_hdr_3addr *nullfunc;
struct ieee80211_sub_if_data *sdata;
struct ieee80211_if_managed *ifmgd;
struct ieee80211_local *local;
struct sk_buff *skb;
if (WARN_ON(vif->type != NL80211_IFTYPE_STATION))
return NULL;
sdata = vif_to_sdata(vif);
ifmgd = &sdata->u.mgd;
local = sdata->local;
skb = dev_alloc_skb(local->hw.extra_tx_headroom + sizeof(*nullfunc));
if (!skb)
return NULL;
skb_reserve(skb, local->hw.extra_tx_headroom);
nullfunc = (struct ieee80211_hdr_3addr *) skb_put(skb,
sizeof(*nullfunc));
memset(nullfunc, 0, sizeof(*nullfunc));
nullfunc->frame_control = cpu_to_le16(IEEE80211_FTYPE_DATA |
IEEE80211_STYPE_NULLFUNC |
IEEE80211_FCTL_TODS);
memcpy(nullfunc->addr1, ifmgd->bssid, ETH_ALEN);
memcpy(nullfunc->addr2, vif->addr, ETH_ALEN);
memcpy(nullfunc->addr3, ifmgd->bssid, ETH_ALEN);
return skb;
}
EXPORT_SYMBOL(ieee80211_nullfunc_get);
struct sk_buff *ieee80211_probereq_get(struct ieee80211_hw *hw,
struct ieee80211_vif *vif,
const u8 *ssid, size_t ssid_len,
const u8 *ie, size_t ie_len)
{
struct ieee80211_sub_if_data *sdata;
struct ieee80211_local *local;
struct ieee80211_hdr_3addr *hdr;
struct sk_buff *skb;
size_t ie_ssid_len;
u8 *pos;
sdata = vif_to_sdata(vif);
local = sdata->local;
ie_ssid_len = 2 + ssid_len;
skb = dev_alloc_skb(local->hw.extra_tx_headroom + sizeof(*hdr) +
ie_ssid_len + ie_len);
if (!skb)
return NULL;
skb_reserve(skb, local->hw.extra_tx_headroom);
hdr = (struct ieee80211_hdr_3addr *) skb_put(skb, sizeof(*hdr));
memset(hdr, 0, sizeof(*hdr));
hdr->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
IEEE80211_STYPE_PROBE_REQ);
memset(hdr->addr1, 0xff, ETH_ALEN);
memcpy(hdr->addr2, vif->addr, ETH_ALEN);
memset(hdr->addr3, 0xff, ETH_ALEN);
pos = skb_put(skb, ie_ssid_len);
*pos++ = WLAN_EID_SSID;
*pos++ = ssid_len;
if (ssid_len)
memcpy(pos, ssid, ssid_len);
pos += ssid_len;
if (ie) {
pos = skb_put(skb, ie_len);
memcpy(pos, ie, ie_len);
}
return skb;
}
EXPORT_SYMBOL(ieee80211_probereq_get);
void ieee80211_rts_get(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
const void *frame, size_t frame_len,
const struct ieee80211_tx_info *frame_txctl,
struct ieee80211_rts *rts)
{
const struct ieee80211_hdr *hdr = frame;
rts->frame_control =
cpu_to_le16(IEEE80211_FTYPE_CTL | IEEE80211_STYPE_RTS);
rts->duration = ieee80211_rts_duration(hw, vif, frame_len,
frame_txctl);
memcpy(rts->ra, hdr->addr1, sizeof(rts->ra));
memcpy(rts->ta, hdr->addr2, sizeof(rts->ta));
}
EXPORT_SYMBOL(ieee80211_rts_get);
void ieee80211_ctstoself_get(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
const void *frame, size_t frame_len,
const struct ieee80211_tx_info *frame_txctl,
struct ieee80211_cts *cts)
{
const struct ieee80211_hdr *hdr = frame;
cts->frame_control =
cpu_to_le16(IEEE80211_FTYPE_CTL | IEEE80211_STYPE_CTS);
cts->duration = ieee80211_ctstoself_duration(hw, vif,
frame_len, frame_txctl);
memcpy(cts->ra, hdr->addr1, sizeof(cts->ra));
}
EXPORT_SYMBOL(ieee80211_ctstoself_get);
struct sk_buff *
ieee80211_get_buffered_bc(struct ieee80211_hw *hw,
struct ieee80211_vif *vif)
{
struct ieee80211_local *local = hw_to_local(hw);
struct sk_buff *skb = NULL;
struct ieee80211_tx_data tx;
struct ieee80211_sub_if_data *sdata;
struct ieee80211_if_ap *bss = NULL;
struct beacon_data *beacon;
struct ieee80211_tx_info *info;
sdata = vif_to_sdata(vif);
bss = &sdata->u.ap;
rcu_read_lock();
beacon = rcu_dereference(bss->beacon);
if (sdata->vif.type != NL80211_IFTYPE_AP || !beacon || !beacon->head)
goto out;
if (bss->dtim_count != 0 || !bss->dtim_bc_mc)
goto out; /* send buffered bc/mc only after DTIM beacon */
while (1) {
skb = skb_dequeue(&bss->ps_bc_buf);
if (!skb)
goto out;
local->total_ps_buffered--;
if (!skb_queue_empty(&bss->ps_bc_buf) && skb->len >= 2) {
struct ieee80211_hdr *hdr =
(struct ieee80211_hdr *) skb->data;
/* more buffered multicast/broadcast frames ==> set
* MoreData flag in IEEE 802.11 header to inform PS
* STAs */
hdr->frame_control |=
cpu_to_le16(IEEE80211_FCTL_MOREDATA);
}
if (!ieee80211_tx_prepare(sdata, &tx, skb))
break;
dev_kfree_skb_any(skb);
}
info = IEEE80211_SKB_CB(skb);
tx.flags |= IEEE80211_TX_PS_BUFFERED;
tx.channel = local->hw.conf.channel;
info->band = tx.channel->band;
if (invoke_tx_handlers(&tx))
skb = NULL;
out:
rcu_read_unlock();
return skb;
}
EXPORT_SYMBOL(ieee80211_get_buffered_bc);
void ieee80211_tx_skb_tid(struct ieee80211_sub_if_data *sdata,
struct sk_buff *skb, int tid)
{
int ac = ieee802_1d_to_ac[tid];
skb_set_mac_header(skb, 0);
skb_set_network_header(skb, 0);
skb_set_transport_header(skb, 0);
skb_set_queue_mapping(skb, ac);
skb->priority = tid;
/*
* The other path calling ieee80211_xmit is from the tasklet,
* and while we can handle concurrent transmissions locking
* requirements are that we do not come into tx with bhs on.
*/
local_bh_disable();
ieee80211_xmit(sdata, skb);
local_bh_enable();
}
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