linux/net/mac80211/agg-rx.c
Ilan Peer 21b7022f13 mac80211: agg-rx: Accept ADDBA request update if timeout did not change
As there is no support for updating an existing ADDBA session with
a peer, we decline the request (while keeping the session active).
However, in case that the timeout did not change, there is no need
to decline the request, so modify the code to reply with status success
in such a case (this is useful for interoperability with APs that send an
ADDBA request update without changing the timeout value).

Signed-off-by: Ilan Peer <ilan.peer@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2018-02-27 11:06:04 +01:00

490 lines
15 KiB
C

/*
* HT handling
*
* Copyright 2003, Jouni Malinen <jkmaline@cc.hut.fi>
* Copyright 2002-2005, Instant802 Networks, Inc.
* Copyright 2005-2006, Devicescape Software, Inc.
* Copyright 2006-2007 Jiri Benc <jbenc@suse.cz>
* Copyright 2007, Michael Wu <flamingice@sourmilk.net>
* Copyright 2007-2010, Intel Corporation
* Copyright(c) 2015-2017 Intel Deutschland GmbH
* Copyright (C) 2018 Intel Corporation
*
* 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.
*/
/**
* DOC: RX A-MPDU aggregation
*
* Aggregation on the RX side requires only implementing the
* @ampdu_action callback that is invoked to start/stop any
* block-ack sessions for RX aggregation.
*
* When RX aggregation is started by the peer, the driver is
* notified via @ampdu_action function, with the
* %IEEE80211_AMPDU_RX_START action, and may reject the request
* in which case a negative response is sent to the peer, if it
* accepts it a positive response is sent.
*
* While the session is active, the device/driver are required
* to de-aggregate frames and pass them up one by one to mac80211,
* which will handle the reorder buffer.
*
* When the aggregation session is stopped again by the peer or
* ourselves, the driver's @ampdu_action function will be called
* with the action %IEEE80211_AMPDU_RX_STOP. In this case, the
* call must not fail.
*/
#include <linux/ieee80211.h>
#include <linux/slab.h>
#include <linux/export.h>
#include <net/mac80211.h>
#include "ieee80211_i.h"
#include "driver-ops.h"
static void ieee80211_free_tid_rx(struct rcu_head *h)
{
struct tid_ampdu_rx *tid_rx =
container_of(h, struct tid_ampdu_rx, rcu_head);
int i;
for (i = 0; i < tid_rx->buf_size; i++)
__skb_queue_purge(&tid_rx->reorder_buf[i]);
kfree(tid_rx->reorder_buf);
kfree(tid_rx->reorder_time);
kfree(tid_rx);
}
void ___ieee80211_stop_rx_ba_session(struct sta_info *sta, u16 tid,
u16 initiator, u16 reason, bool tx)
{
struct ieee80211_local *local = sta->local;
struct tid_ampdu_rx *tid_rx;
struct ieee80211_ampdu_params params = {
.sta = &sta->sta,
.action = IEEE80211_AMPDU_RX_STOP,
.tid = tid,
.amsdu = false,
.timeout = 0,
.ssn = 0,
};
lockdep_assert_held(&sta->ampdu_mlme.mtx);
tid_rx = rcu_dereference_protected(sta->ampdu_mlme.tid_rx[tid],
lockdep_is_held(&sta->ampdu_mlme.mtx));
if (!test_bit(tid, sta->ampdu_mlme.agg_session_valid))
return;
RCU_INIT_POINTER(sta->ampdu_mlme.tid_rx[tid], NULL);
__clear_bit(tid, sta->ampdu_mlme.agg_session_valid);
ht_dbg(sta->sdata,
"Rx BA session stop requested for %pM tid %u %s reason: %d\n",
sta->sta.addr, tid,
initiator == WLAN_BACK_RECIPIENT ? "recipient" : "initiator",
(int)reason);
if (drv_ampdu_action(local, sta->sdata, &params))
sdata_info(sta->sdata,
"HW problem - can not stop rx aggregation for %pM tid %d\n",
sta->sta.addr, tid);
/* check if this is a self generated aggregation halt */
if (initiator == WLAN_BACK_RECIPIENT && tx)
ieee80211_send_delba(sta->sdata, sta->sta.addr,
tid, WLAN_BACK_RECIPIENT, reason);
/*
* return here in case tid_rx is not assigned - which will happen if
* IEEE80211_HW_SUPPORTS_REORDERING_BUFFER is set.
*/
if (!tid_rx)
return;
del_timer_sync(&tid_rx->session_timer);
/* make sure ieee80211_sta_reorder_release() doesn't re-arm the timer */
spin_lock_bh(&tid_rx->reorder_lock);
tid_rx->removed = true;
spin_unlock_bh(&tid_rx->reorder_lock);
del_timer_sync(&tid_rx->reorder_timer);
call_rcu(&tid_rx->rcu_head, ieee80211_free_tid_rx);
}
void __ieee80211_stop_rx_ba_session(struct sta_info *sta, u16 tid,
u16 initiator, u16 reason, bool tx)
{
mutex_lock(&sta->ampdu_mlme.mtx);
___ieee80211_stop_rx_ba_session(sta, tid, initiator, reason, tx);
mutex_unlock(&sta->ampdu_mlme.mtx);
}
void ieee80211_stop_rx_ba_session(struct ieee80211_vif *vif, u16 ba_rx_bitmap,
const u8 *addr)
{
struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
struct sta_info *sta;
int i;
rcu_read_lock();
sta = sta_info_get_bss(sdata, addr);
if (!sta) {
rcu_read_unlock();
return;
}
for (i = 0; i < IEEE80211_NUM_TIDS; i++)
if (ba_rx_bitmap & BIT(i))
set_bit(i, sta->ampdu_mlme.tid_rx_stop_requested);
ieee80211_queue_work(&sta->local->hw, &sta->ampdu_mlme.work);
rcu_read_unlock();
}
EXPORT_SYMBOL(ieee80211_stop_rx_ba_session);
/*
* After accepting the AddBA Request we activated a timer,
* resetting it after each frame that arrives from the originator.
*/
static void sta_rx_agg_session_timer_expired(struct timer_list *t)
{
struct tid_ampdu_rx *tid_rx = from_timer(tid_rx, t, session_timer);
struct sta_info *sta = tid_rx->sta;
u8 tid = tid_rx->tid;
unsigned long timeout;
timeout = tid_rx->last_rx + TU_TO_JIFFIES(tid_rx->timeout);
if (time_is_after_jiffies(timeout)) {
mod_timer(&tid_rx->session_timer, timeout);
return;
}
ht_dbg(sta->sdata, "RX session timer expired on %pM tid %d\n",
sta->sta.addr, tid);
set_bit(tid, sta->ampdu_mlme.tid_rx_timer_expired);
ieee80211_queue_work(&sta->local->hw, &sta->ampdu_mlme.work);
}
static void sta_rx_agg_reorder_timer_expired(struct timer_list *t)
{
struct tid_ampdu_rx *tid_rx = from_timer(tid_rx, t, reorder_timer);
rcu_read_lock();
ieee80211_release_reorder_timeout(tid_rx->sta, tid_rx->tid);
rcu_read_unlock();
}
static void ieee80211_send_addba_resp(struct ieee80211_sub_if_data *sdata, u8 *da, u16 tid,
u8 dialog_token, u16 status, u16 policy,
u16 buf_size, u16 timeout)
{
struct ieee80211_local *local = sdata->local;
struct sk_buff *skb;
struct ieee80211_mgmt *mgmt;
bool amsdu = ieee80211_hw_check(&local->hw, SUPPORTS_AMSDU_IN_AMPDU);
u16 capab;
skb = dev_alloc_skb(sizeof(*mgmt) + local->hw.extra_tx_headroom);
if (!skb)
return;
skb_reserve(skb, local->hw.extra_tx_headroom);
mgmt = skb_put_zero(skb, 24);
memcpy(mgmt->da, da, ETH_ALEN);
memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
if (sdata->vif.type == NL80211_IFTYPE_AP ||
sdata->vif.type == NL80211_IFTYPE_AP_VLAN ||
sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
else if (sdata->vif.type == NL80211_IFTYPE_STATION)
memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN);
else if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
memcpy(mgmt->bssid, sdata->u.ibss.bssid, ETH_ALEN);
mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
IEEE80211_STYPE_ACTION);
skb_put(skb, 1 + sizeof(mgmt->u.action.u.addba_resp));
mgmt->u.action.category = WLAN_CATEGORY_BACK;
mgmt->u.action.u.addba_resp.action_code = WLAN_ACTION_ADDBA_RESP;
mgmt->u.action.u.addba_resp.dialog_token = dialog_token;
capab = (u16)(amsdu << 0); /* bit 0 A-MSDU support */
capab |= (u16)(policy << 1); /* bit 1 aggregation policy */
capab |= (u16)(tid << 2); /* bit 5:2 TID number */
capab |= (u16)(buf_size << 6); /* bit 15:6 max size of aggregation */
mgmt->u.action.u.addba_resp.capab = cpu_to_le16(capab);
mgmt->u.action.u.addba_resp.timeout = cpu_to_le16(timeout);
mgmt->u.action.u.addba_resp.status = cpu_to_le16(status);
ieee80211_tx_skb(sdata, skb);
}
void ___ieee80211_start_rx_ba_session(struct sta_info *sta,
u8 dialog_token, u16 timeout,
u16 start_seq_num, u16 ba_policy, u16 tid,
u16 buf_size, bool tx, bool auto_seq)
{
struct ieee80211_local *local = sta->sdata->local;
struct tid_ampdu_rx *tid_agg_rx;
struct ieee80211_ampdu_params params = {
.sta = &sta->sta,
.action = IEEE80211_AMPDU_RX_START,
.tid = tid,
.amsdu = false,
.timeout = timeout,
.ssn = start_seq_num,
};
int i, ret = -EOPNOTSUPP;
u16 status = WLAN_STATUS_REQUEST_DECLINED;
if (tid >= IEEE80211_FIRST_TSPEC_TSID) {
ht_dbg(sta->sdata,
"STA %pM requests BA session on unsupported tid %d\n",
sta->sta.addr, tid);
goto end;
}
if (!sta->sta.ht_cap.ht_supported) {
ht_dbg(sta->sdata,
"STA %pM erroneously requests BA session on tid %d w/o QoS\n",
sta->sta.addr, tid);
/* send a response anyway, it's an error case if we get here */
goto end;
}
if (test_sta_flag(sta, WLAN_STA_BLOCK_BA)) {
ht_dbg(sta->sdata,
"Suspend in progress - Denying ADDBA request (%pM tid %d)\n",
sta->sta.addr, tid);
goto end;
}
/* sanity check for incoming parameters:
* check if configuration can support the BA policy
* and if buffer size does not exceeds max value */
/* XXX: check own ht delayed BA capability?? */
if (((ba_policy != 1) &&
(!(sta->sta.ht_cap.cap & IEEE80211_HT_CAP_DELAY_BA))) ||
(buf_size > IEEE80211_MAX_AMPDU_BUF)) {
status = WLAN_STATUS_INVALID_QOS_PARAM;
ht_dbg_ratelimited(sta->sdata,
"AddBA Req with bad params from %pM on tid %u. policy %d, buffer size %d\n",
sta->sta.addr, tid, ba_policy, buf_size);
goto end;
}
/* determine default buffer size */
if (buf_size == 0)
buf_size = IEEE80211_MAX_AMPDU_BUF;
/* make sure the size doesn't exceed the maximum supported by the hw */
if (buf_size > sta->sta.max_rx_aggregation_subframes)
buf_size = sta->sta.max_rx_aggregation_subframes;
params.buf_size = buf_size;
ht_dbg(sta->sdata, "AddBA Req buf_size=%d for %pM\n",
buf_size, sta->sta.addr);
/* examine state machine */
lockdep_assert_held(&sta->ampdu_mlme.mtx);
if (test_bit(tid, sta->ampdu_mlme.agg_session_valid)) {
if (sta->ampdu_mlme.tid_rx_token[tid] == dialog_token) {
struct tid_ampdu_rx *tid_rx;
ht_dbg_ratelimited(sta->sdata,
"updated AddBA Req from %pM on tid %u\n",
sta->sta.addr, tid);
/* We have no API to update the timeout value in the
* driver so reject the timeout update if the timeout
* changed. If if did not change, i.e., no real update,
* just reply with success.
*/
rcu_read_lock();
tid_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
if (tid_rx && tid_rx->timeout == timeout)
status = WLAN_STATUS_SUCCESS;
else
status = WLAN_STATUS_REQUEST_DECLINED;
rcu_read_unlock();
goto end;
}
ht_dbg_ratelimited(sta->sdata,
"unexpected AddBA Req from %pM on tid %u\n",
sta->sta.addr, tid);
/* delete existing Rx BA session on the same tid */
___ieee80211_stop_rx_ba_session(sta, tid, WLAN_BACK_RECIPIENT,
WLAN_STATUS_UNSPECIFIED_QOS,
false);
}
if (ieee80211_hw_check(&local->hw, SUPPORTS_REORDERING_BUFFER)) {
ret = drv_ampdu_action(local, sta->sdata, &params);
ht_dbg(sta->sdata,
"Rx A-MPDU request on %pM tid %d result %d\n",
sta->sta.addr, tid, ret);
if (!ret)
status = WLAN_STATUS_SUCCESS;
goto end;
}
/* prepare A-MPDU MLME for Rx aggregation */
tid_agg_rx = kzalloc(sizeof(*tid_agg_rx), GFP_KERNEL);
if (!tid_agg_rx)
goto end;
spin_lock_init(&tid_agg_rx->reorder_lock);
/* rx timer */
timer_setup(&tid_agg_rx->session_timer,
sta_rx_agg_session_timer_expired, TIMER_DEFERRABLE);
/* rx reorder timer */
timer_setup(&tid_agg_rx->reorder_timer,
sta_rx_agg_reorder_timer_expired, 0);
/* prepare reordering buffer */
tid_agg_rx->reorder_buf =
kcalloc(buf_size, sizeof(struct sk_buff_head), GFP_KERNEL);
tid_agg_rx->reorder_time =
kcalloc(buf_size, sizeof(unsigned long), GFP_KERNEL);
if (!tid_agg_rx->reorder_buf || !tid_agg_rx->reorder_time) {
kfree(tid_agg_rx->reorder_buf);
kfree(tid_agg_rx->reorder_time);
kfree(tid_agg_rx);
goto end;
}
for (i = 0; i < buf_size; i++)
__skb_queue_head_init(&tid_agg_rx->reorder_buf[i]);
ret = drv_ampdu_action(local, sta->sdata, &params);
ht_dbg(sta->sdata, "Rx A-MPDU request on %pM tid %d result %d\n",
sta->sta.addr, tid, ret);
if (ret) {
kfree(tid_agg_rx->reorder_buf);
kfree(tid_agg_rx->reorder_time);
kfree(tid_agg_rx);
goto end;
}
/* update data */
tid_agg_rx->ssn = start_seq_num;
tid_agg_rx->head_seq_num = start_seq_num;
tid_agg_rx->buf_size = buf_size;
tid_agg_rx->timeout = timeout;
tid_agg_rx->stored_mpdu_num = 0;
tid_agg_rx->auto_seq = auto_seq;
tid_agg_rx->started = false;
tid_agg_rx->reorder_buf_filtered = 0;
tid_agg_rx->tid = tid;
tid_agg_rx->sta = sta;
status = WLAN_STATUS_SUCCESS;
/* activate it for RX */
rcu_assign_pointer(sta->ampdu_mlme.tid_rx[tid], tid_agg_rx);
if (timeout) {
mod_timer(&tid_agg_rx->session_timer, TU_TO_EXP_TIME(timeout));
tid_agg_rx->last_rx = jiffies;
}
end:
if (status == WLAN_STATUS_SUCCESS) {
__set_bit(tid, sta->ampdu_mlme.agg_session_valid);
__clear_bit(tid, sta->ampdu_mlme.unexpected_agg);
sta->ampdu_mlme.tid_rx_token[tid] = dialog_token;
}
if (tx)
ieee80211_send_addba_resp(sta->sdata, sta->sta.addr, tid,
dialog_token, status, 1, buf_size,
timeout);
}
static void __ieee80211_start_rx_ba_session(struct sta_info *sta,
u8 dialog_token, u16 timeout,
u16 start_seq_num, u16 ba_policy,
u16 tid, u16 buf_size, bool tx,
bool auto_seq)
{
mutex_lock(&sta->ampdu_mlme.mtx);
___ieee80211_start_rx_ba_session(sta, dialog_token, timeout,
start_seq_num, ba_policy, tid,
buf_size, tx, auto_seq);
mutex_unlock(&sta->ampdu_mlme.mtx);
}
void ieee80211_process_addba_request(struct ieee80211_local *local,
struct sta_info *sta,
struct ieee80211_mgmt *mgmt,
size_t len)
{
u16 capab, tid, timeout, ba_policy, buf_size, start_seq_num;
u8 dialog_token;
/* extract session parameters from addba request frame */
dialog_token = mgmt->u.action.u.addba_req.dialog_token;
timeout = le16_to_cpu(mgmt->u.action.u.addba_req.timeout);
start_seq_num =
le16_to_cpu(mgmt->u.action.u.addba_req.start_seq_num) >> 4;
capab = le16_to_cpu(mgmt->u.action.u.addba_req.capab);
ba_policy = (capab & IEEE80211_ADDBA_PARAM_POLICY_MASK) >> 1;
tid = (capab & IEEE80211_ADDBA_PARAM_TID_MASK) >> 2;
buf_size = (capab & IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK) >> 6;
__ieee80211_start_rx_ba_session(sta, dialog_token, timeout,
start_seq_num, ba_policy, tid,
buf_size, true, false);
}
void ieee80211_manage_rx_ba_offl(struct ieee80211_vif *vif,
const u8 *addr, unsigned int tid)
{
struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
struct ieee80211_local *local = sdata->local;
struct sta_info *sta;
rcu_read_lock();
sta = sta_info_get_bss(sdata, addr);
if (!sta)
goto unlock;
set_bit(tid, sta->ampdu_mlme.tid_rx_manage_offl);
ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work);
unlock:
rcu_read_unlock();
}
EXPORT_SYMBOL(ieee80211_manage_rx_ba_offl);
void ieee80211_rx_ba_timer_expired(struct ieee80211_vif *vif,
const u8 *addr, unsigned int tid)
{
struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
struct ieee80211_local *local = sdata->local;
struct sta_info *sta;
rcu_read_lock();
sta = sta_info_get_bss(sdata, addr);
if (!sta)
goto unlock;
set_bit(tid, sta->ampdu_mlme.tid_rx_timer_expired);
ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work);
unlock:
rcu_read_unlock();
}
EXPORT_SYMBOL(ieee80211_rx_ba_timer_expired);