mac80211: handle protection mode, RIFS and ADDBA for HT IBSS

* Follow 802.11n-2009 9.13.3.1 for protection mode and ADDBA
* Send ADDBA only to HT STAs - implement 11.5.1.1 partially

Signed-off-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: Mathias Kretschmer <mathias.kretschmer@fokus.fraunhofer.de>
Reviewed-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 18 insertions, 0 deletions

diff --git a/net/mac80211/ibss.c b/net/mac80211/ibss.c
index 7d84af70132f..a82f6b4adb58 100644
--- a/net/mac80211/ibss.c
+++ b/net/mac80211/ibss.c
@@ -896,6 +896,7 @@ int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
                         struct cfg80211_ibss_params *params)
 {
         struct sk_buff *skb;
+        u32 changed = 0;
 
         skb = dev_alloc_skb(sdata->local->hw.extra_tx_headroom +
                             36 /* bitrates */ +
@@ -951,6 +952,23 @@ int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
         ieee80211_recalc_idle(sdata->local);
         mutex_unlock(&sdata->local->mtx);
 
+        /*
+         * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is
+         * reserved, but an HT STA shall protect HT transmissions as though
+         * the HT Protection field were set to non-HT mixed mode.
+         *
+         * In an IBSS, the RIFS Mode field of the HT Operation element is
+         * also reserved, but an HT STA shall operate as though this field
+         * were set to 1.
+         */
+
+        sdata->vif.bss_conf.ht_operation_mode |=
+                  IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED
+                | IEEE80211_HT_PARAM_RIFS_MODE;
+
+        changed |= BSS_CHANGED_HT;
+        ieee80211_bss_info_change_notify(sdata, changed);
+
         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 
         return 0;