mac80211: adding 802.11n essential A-MPDU addBA capability
This patch adds the capability to identify and answer an add block ACK
request.
As this series of patches only adds HT handling with no aggregations,
(A-MPDU aggregations acceptance is not obligatory according to 802.11n
draft) we are currently sending back a refusal upon this request.
Signed-off-by: Ron Rindjunsky <ron.rindjunsky@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/mac80211/ieee80211_sta.c b/net/mac80211/ieee80211_sta.c
index 1f47afe..1d553d7 100644
--- a/net/mac80211/ieee80211_sta.c
+++ b/net/mac80211/ieee80211_sta.c
@@ -57,6 +57,13 @@
#define ERP_INFO_USE_PROTECTION BIT(1)
+/* mgmt header + 1 byte action code */
+#define IEEE80211_MIN_ACTION_SIZE (24 + 1)
+
+#define IEEE80211_ADDBA_PARAM_POLICY_MASK 0x0002
+#define IEEE80211_ADDBA_PARAM_TID_MASK 0x003C
+#define IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK 0xFFA0
+
static void ieee80211_send_probe_req(struct net_device *dev, u8 *dst,
u8 *ssid, size_t ssid_len);
static struct ieee80211_sta_bss *
@@ -987,6 +994,91 @@
elems.challenge_len + 2, 1);
}
+static void ieee80211_send_addba_resp(struct net_device *dev, u8 *da, u16 tid,
+ u8 dialog_token, u16 status, u16 policy,
+ u16 buf_size, u16 timeout)
+{
+ struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
+ struct ieee80211_if_sta *ifsta = &sdata->u.sta;
+ struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
+ struct sk_buff *skb;
+ struct ieee80211_mgmt *mgmt;
+ u16 capab;
+
+ skb = dev_alloc_skb(sizeof(*mgmt) + local->hw.extra_tx_headroom);
+ if (!skb) {
+ printk(KERN_DEBUG "%s: failed to allocate buffer "
+ "for addba resp frame\n", dev->name);
+ return;
+ }
+
+ skb_reserve(skb, local->hw.extra_tx_headroom);
+ mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24);
+ memset(mgmt, 0, 24);
+ memcpy(mgmt->da, da, ETH_ALEN);
+ memcpy(mgmt->sa, dev->dev_addr, ETH_ALEN);
+ if (sdata->type == IEEE80211_IF_TYPE_AP)
+ memcpy(mgmt->bssid, dev->dev_addr, ETH_ALEN);
+ else
+ memcpy(mgmt->bssid, ifsta->bssid, ETH_ALEN);
+ mgmt->frame_control = IEEE80211_FC(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)(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_sta_tx(dev, skb, 0);
+
+ return;
+}
+
+static void ieee80211_sta_process_addba_request(struct net_device *dev,
+ struct ieee80211_mgmt *mgmt,
+ size_t len)
+{
+ struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
+ struct sta_info *sta;
+ u16 capab, tid, timeout, ba_policy, buf_size, status;
+ u8 dialog_token;
+
+ sta = sta_info_get(local, mgmt->sa);
+ if (!sta)
+ return;
+
+ /* 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);
+
+ 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;
+
+ /* TODO - currently aggregation is declined (A-MPDU add BA request
+ * acceptance is not obligatory by 802.11n draft), but here is
+ * the entry point for dealing with it */
+#ifdef MAC80211_HT_DEBUG
+ if (net_ratelimit())
+ printk(KERN_DEBUG "Add Block Ack request arrived,"
+ " currently denying it\n");
+#endif /* MAC80211_HT_DEBUG */
+
+ status = WLAN_STATUS_REQUEST_DECLINED;
+
+ ieee80211_send_addba_resp(sta->dev, sta->addr, tid, dialog_token,
+ status, 1, buf_size, timeout);
+ sta_info_put(sta);
+}
static void ieee80211_rx_mgmt_auth(struct net_device *dev,
struct ieee80211_if_sta *ifsta,
@@ -1870,6 +1962,34 @@
ieee80211_sta_tx(dev, skb, 0);
}
+void ieee80211_rx_mgmt_action(struct net_device *dev,
+ struct ieee80211_if_sta *ifsta,
+ struct ieee80211_mgmt *mgmt,
+ size_t len)
+{
+ if (len < IEEE80211_MIN_ACTION_SIZE)
+ return;
+
+ switch (mgmt->u.action.category) {
+ case WLAN_CATEGORY_BACK:
+ switch (mgmt->u.action.u.addba_req.action_code) {
+ case WLAN_ACTION_ADDBA_REQ:
+ if (len < (IEEE80211_MIN_ACTION_SIZE +
+ sizeof(mgmt->u.action.u.addba_req)))
+ break;
+ ieee80211_sta_process_addba_request(dev, mgmt, len);
+ break;
+ default:
+ if (net_ratelimit())
+ printk(KERN_DEBUG "%s: received unsupported BACK\n",
+ dev->name);
+ break;
+ }
+ break;
+ default:
+ break;
+ }
+}
void ieee80211_sta_rx_mgmt(struct net_device *dev, struct sk_buff *skb,
struct ieee80211_rx_status *rx_status)
@@ -1899,6 +2019,7 @@
case IEEE80211_STYPE_REASSOC_RESP:
case IEEE80211_STYPE_DEAUTH:
case IEEE80211_STYPE_DISASSOC:
+ case IEEE80211_STYPE_ACTION:
skb_queue_tail(&ifsta->skb_queue, skb);
queue_work(local->hw.workqueue, &ifsta->work);
return;
@@ -1956,6 +2077,9 @@
case IEEE80211_STYPE_DISASSOC:
ieee80211_rx_mgmt_disassoc(dev, ifsta, mgmt, skb->len);
break;
+ case IEEE80211_STYPE_ACTION:
+ ieee80211_rx_mgmt_action(dev, ifsta, mgmt, skb->len);
+ break;
}
kfree_skb(skb);