mac80211: 11h - Handling measurement request

This patch handles the 11h measurement request information element.
This is minimal requested implementation - refuse measurement.

Signed-off-by: Assaf Krauss <assaf.krauss@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

2 files changed, 88 insertions, 0 deletions

diff --git a/include/linux/ieee80211.h b/include/linux/ieee80211.h
index 8546f09e462c..cffd6d0094f9 100644
--- a/include/linux/ieee80211.h
+++ b/include/linux/ieee80211.h
@@ -739,11 +739,21 @@ struct ieee80211_ht_addt_info {
 #define WLAN_CAPABILITY_SHORT_PREAMBLE  (1<<5)
 #define WLAN_CAPABILITY_PBCC            (1<<6)
 #define WLAN_CAPABILITY_CHANNEL_AGILITY (1<<7)
+
 /* 802.11h */
 #define WLAN_CAPABILITY_SPECTRUM_MGMT   (1<<8)
 #define WLAN_CAPABILITY_QOS             (1<<9)
 #define WLAN_CAPABILITY_SHORT_SLOT_TIME (1<<10)
 #define WLAN_CAPABILITY_DSSS_OFDM       (1<<13)
+/* measurement */
+#define IEEE80211_SPCT_MSR_RPRT_MODE_LATE       (1<<0)
+#define IEEE80211_SPCT_MSR_RPRT_MODE_INCAPABLE  (1<<1)
+#define IEEE80211_SPCT_MSR_RPRT_MODE_REFUSED    (1<<2)
+
+#define IEEE80211_SPCT_MSR_RPRT_TYPE_BASIC      0
+#define IEEE80211_SPCT_MSR_RPRT_TYPE_CCA        1
+#define IEEE80211_SPCT_MSR_RPRT_TYPE_RPI        2
+
 
 /* 802.11g ERP information element */
 #define WLAN_ERP_NON_ERP_PRESENT (1<<0)
diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index 32453561fe32..6d9a4facf9dd 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -1720,6 +1720,71 @@ void ieee80211_sta_tear_down_BA_sessions(struct net_device *dev, u8 *addr)
         }
 }
 
+static void ieee80211_send_refuse_measurement_request(struct net_device *dev,
+                                        struct ieee80211_msrment_ie *request_ie,
+                                        const u8 *da, const u8 *bssid,
+                                        u8 dialog_token)
+{
+        struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
+        struct sk_buff *skb;
+        struct ieee80211_mgmt *msr_report;
+
+        skb = dev_alloc_skb(sizeof(*msr_report) + local->hw.extra_tx_headroom +
+                                sizeof(struct ieee80211_msrment_ie));
+
+        if (!skb) {
+                printk(KERN_ERR "%s: failed to allocate buffer for "
+                                "measurement report frame\n", dev->name);
+                return;
+        }
+
+        skb_reserve(skb, local->hw.extra_tx_headroom);
+        msr_report = (struct ieee80211_mgmt *)skb_put(skb, 24);
+        memset(msr_report, 0, 24);
+        memcpy(msr_report->da, da, ETH_ALEN);
+        memcpy(msr_report->sa, dev->dev_addr, ETH_ALEN);
+        memcpy(msr_report->bssid, bssid, ETH_ALEN);
+        msr_report->frame_control = IEEE80211_FC(IEEE80211_FTYPE_MGMT,
+                                                IEEE80211_STYPE_ACTION);
+
+        skb_put(skb, 1 + sizeof(msr_report->u.action.u.measurement));
+        msr_report->u.action.category = WLAN_CATEGORY_SPECTRUM_MGMT;
+        msr_report->u.action.u.measurement.action_code =
+                                WLAN_ACTION_SPCT_MSR_RPRT;
+        msr_report->u.action.u.measurement.dialog_token = dialog_token;
+
+        msr_report->u.action.u.measurement.element_id = WLAN_EID_MEASURE_REPORT;
+        msr_report->u.action.u.measurement.length =
+                        sizeof(struct ieee80211_msrment_ie);
+
+        memset(&msr_report->u.action.u.measurement.msr_elem, 0,
+                sizeof(struct ieee80211_msrment_ie));
+        msr_report->u.action.u.measurement.msr_elem.token = request_ie->token;
+        msr_report->u.action.u.measurement.msr_elem.mode |=
+                        IEEE80211_SPCT_MSR_RPRT_MODE_REFUSED;
+        msr_report->u.action.u.measurement.msr_elem.type = request_ie->type;
+
+        ieee80211_sta_tx(dev, skb, 0);
+}
+
+static void ieee80211_sta_process_measurement_req(struct net_device *dev,
+                                                struct ieee80211_mgmt *mgmt,
+                                                size_t len)
+{
+        /*
+         * Ignoring measurement request is spec violation.
+         * Mandatory measurements must be reported optional
+         * measurements might be refused or reported incapable
+         * For now just refuse
+         * TODO: Answer basic measurement as unmeasured
+         */
+        ieee80211_send_refuse_measurement_request(dev,
+                        &mgmt->u.action.u.measurement.msr_elem,
+                        mgmt->sa, mgmt->bssid,
+                        mgmt->u.action.u.measurement.dialog_token);
+}
+
+
 static void ieee80211_rx_mgmt_auth(struct net_device *dev,
                                    struct ieee80211_if_sta *ifsta,
                                    struct ieee80211_mgmt *mgmt,
@@ -3044,11 +3109,24 @@ static void ieee80211_rx_mgmt_action(struct net_device *dev,
                                      struct ieee80211_rx_status *rx_status)
 {
         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
+        struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
 
         if (len < IEEE80211_MIN_ACTION_SIZE)
                 return;
 
         switch (mgmt->u.action.category) {
+        case WLAN_CATEGORY_SPECTRUM_MGMT:
+                if (local->hw.conf.channel->band != IEEE80211_BAND_5GHZ)
+                        break;
+                switch (mgmt->u.action.u.chan_switch.action_code) {
+                case WLAN_ACTION_SPCT_MSR_REQ:
+                        if (len < (IEEE80211_MIN_ACTION_SIZE +
+                                   sizeof(mgmt->u.action.u.measurement)))
+                                break;
+                        ieee80211_sta_process_measurement_req(dev, mgmt, len);
+                        break;
+                }
+                break;
         case WLAN_CATEGORY_BACK:
                 switch (mgmt->u.action.u.addba_req.action_code) {
                 case WLAN_ACTION_ADDBA_REQ: