linux/net/mac80211/wme.c
Thomas Pedersen 6cc00d545a mac80211: QoS multicast frames have No Ack policy
Previously QoS multicast frames had the Normal Acknowledgment QoS
control bits set. This would cause broadcast frames to be discarded by
peers with which we have a BA session, since their sequence number would
fall outside the allowed range. Set No Ack QoS control bits on multicast
QoS frames and filter these in de-aggregation code.

Signed-off-by: Thomas Pedersen <thomas@cozybit.com>

v2: Use proper QoS Ack Policy ctl field mask (Christian)

v3: Clean up conditional (Johannes)
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2011-11-09 16:05:48 -05:00

162 lines
3.7 KiB
C

/*
* Copyright 2004, Instant802 Networks, Inc.
*
* 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.
*/
#include <linux/netdevice.h>
#include <linux/skbuff.h>
#include <linux/module.h>
#include <linux/if_arp.h>
#include <linux/types.h>
#include <net/ip.h>
#include <net/pkt_sched.h>
#include <net/mac80211.h>
#include "ieee80211_i.h"
#include "wme.h"
/* Default mapping in classifier to work with default
* queue setup.
*/
const int ieee802_1d_to_ac[8] = {
IEEE80211_AC_BE,
IEEE80211_AC_BK,
IEEE80211_AC_BK,
IEEE80211_AC_BE,
IEEE80211_AC_VI,
IEEE80211_AC_VI,
IEEE80211_AC_VO,
IEEE80211_AC_VO
};
static int wme_downgrade_ac(struct sk_buff *skb)
{
switch (skb->priority) {
case 6:
case 7:
skb->priority = 5; /* VO -> VI */
return 0;
case 4:
case 5:
skb->priority = 3; /* VI -> BE */
return 0;
case 0:
case 3:
skb->priority = 2; /* BE -> BK */
return 0;
default:
return -1;
}
}
/* Indicate which queue to use. */
u16 ieee80211_select_queue(struct ieee80211_sub_if_data *sdata,
struct sk_buff *skb)
{
struct ieee80211_local *local = sdata->local;
struct sta_info *sta = NULL;
const u8 *ra = NULL;
bool qos = false;
if (local->hw.queues < 4 || skb->len < 6) {
skb->priority = 0; /* required for correct WPA/11i MIC */
return min_t(u16, local->hw.queues - 1, IEEE80211_AC_BE);
}
rcu_read_lock();
switch (sdata->vif.type) {
case NL80211_IFTYPE_AP_VLAN:
sta = rcu_dereference(sdata->u.vlan.sta);
if (sta) {
qos = test_sta_flag(sta, WLAN_STA_WME);
break;
}
case NL80211_IFTYPE_AP:
ra = skb->data;
break;
case NL80211_IFTYPE_WDS:
ra = sdata->u.wds.remote_addr;
break;
#ifdef CONFIG_MAC80211_MESH
case NL80211_IFTYPE_MESH_POINT:
ra = skb->data;
break;
#endif
case NL80211_IFTYPE_STATION:
ra = sdata->u.mgd.bssid;
break;
case NL80211_IFTYPE_ADHOC:
ra = skb->data;
break;
default:
break;
}
if (!sta && ra && !is_multicast_ether_addr(ra)) {
sta = sta_info_get(sdata, ra);
if (sta)
qos = test_sta_flag(sta, WLAN_STA_WME);
}
rcu_read_unlock();
if (!qos) {
skb->priority = 0; /* required for correct WPA/11i MIC */
return IEEE80211_AC_BE;
}
/* use the data classifier to determine what 802.1d tag the
* data frame has */
skb->priority = cfg80211_classify8021d(skb);
return ieee80211_downgrade_queue(local, skb);
}
u16 ieee80211_downgrade_queue(struct ieee80211_local *local,
struct sk_buff *skb)
{
/* in case we are a client verify acm is not set for this ac */
while (unlikely(local->wmm_acm & BIT(skb->priority))) {
if (wme_downgrade_ac(skb)) {
/*
* This should not really happen. The AP has marked all
* lower ACs to require admission control which is not
* a reasonable configuration. Allow the frame to be
* transmitted using AC_BK as a workaround.
*/
break;
}
}
/* look up which queue to use for frames with this 1d tag */
return ieee802_1d_to_ac[skb->priority];
}
void ieee80211_set_qos_hdr(struct ieee80211_sub_if_data *sdata,
struct sk_buff *skb)
{
struct ieee80211_hdr *hdr = (void *)skb->data;
/* Fill in the QoS header if there is one. */
if (ieee80211_is_data_qos(hdr->frame_control)) {
u8 *p = ieee80211_get_qos_ctl(hdr);
u8 ack_policy, tid;
tid = skb->priority & IEEE80211_QOS_CTL_TAG1D_MASK;
/* preserve EOSP bit */
ack_policy = *p & IEEE80211_QOS_CTL_EOSP;
if (unlikely(sdata->local->wifi_wme_noack_test) ||
is_multicast_ether_addr(hdr->addr1))
ack_policy |= IEEE80211_QOS_CTL_ACK_POLICY_NOACK;
/* qos header is 2 bytes */
*p++ = ack_policy | tid;
*p = ieee80211_vif_is_mesh(&sdata->vif) ?
(IEEE80211_QOS_CTL_MESH_CONTROL_PRESENT >> 8) : 0;
}
}