mac80211: Save probe response data for bss

Allow setting a probe response template for an interface operating in
AP mode. Low level drivers are notified about changes in the probe
response template and are able to retrieve a copy of the current probe
response. This data can, for example, be uploaded to hardware as a
template.

Signed-off-by: Guy Eilam <guy@wizery.com>
Signed-off-by: Arik Nemtsov <arik@wizery.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index ab6cb56..2b413d3 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -2415,6 +2415,37 @@
 }
 EXPORT_SYMBOL(ieee80211_beacon_get_tim);
 
+struct sk_buff *ieee80211_proberesp_get(struct ieee80211_hw *hw,
+					struct ieee80211_vif *vif)
+{
+	struct ieee80211_if_ap *ap = NULL;
+	struct sk_buff *presp = NULL, *skb = NULL;
+	struct ieee80211_hdr *hdr;
+	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
+
+	if (sdata->vif.type != NL80211_IFTYPE_AP)
+		return NULL;
+
+	rcu_read_lock();
+
+	ap = &sdata->u.ap;
+	presp = rcu_dereference(ap->probe_resp);
+	if (!presp)
+		goto out;
+
+	skb = skb_copy(presp, GFP_ATOMIC);
+	if (!skb)
+		goto out;
+
+	hdr = (struct ieee80211_hdr *) skb->data;
+	memset(hdr->addr1, 0, sizeof(hdr->addr1));
+
+out:
+	rcu_read_unlock();
+	return skb;
+}
+EXPORT_SYMBOL(ieee80211_proberesp_get);
+
 struct sk_buff *ieee80211_pspoll_get(struct ieee80211_hw *hw,
 				     struct ieee80211_vif *vif)
 {