mac80211: Add support for tx_control_port

Signed-off-by: Denis Kenzior <[e-mail]>
Signed-off-by: Johannes Berg <[e-mail]>

net/mac80211/cfg.c

···
 	.add_nan_func = ieee80211_add_nan_func,
 	.del_nan_func = ieee80211_del_nan_func,
 	.set_multicast_to_unicast = ieee80211_set_multicast_to_unicast,
+	.tx_control_port = ieee80211_tx_control_port,
 };

net/mac80211/ieee80211_i.h

···
 void ieee80211_check_fast_xmit_all(struct ieee80211_local *local);
 void ieee80211_check_fast_xmit_iface(struct ieee80211_sub_if_data *sdata);
 void ieee80211_clear_fast_xmit(struct sta_info *sta);
+int ieee80211_tx_control_port(struct wiphy *wiphy, struct net_device *dev,
+			      const u8 *buf, size_t len,
+			      const u8 *dest, __be16 proto, bool unencrypted);
 
 /* HT */
 void ieee80211_apply_htcap_overrides(struct ieee80211_sub_if_data *sdata,

net/mac80211/tx.c

···
 	ieee80211_xmit(sdata, NULL, skb);
 	local_bh_enable();
 }
+
+int ieee80211_tx_control_port(struct wiphy *wiphy, struct net_device *dev,
+			      const u8 *buf, size_t len,
+			      const u8 *dest, __be16 proto, bool unencrypted)
+{
+	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
+	struct ieee80211_local *local = sdata->local;
+	struct sk_buff *skb;
+	struct ethhdr *ehdr;
+	u32 flags;
+
+	/* Only accept CONTROL_PORT_PROTOCOL configured in CONNECT/ASSOCIATE
+	 * or Pre-Authentication
+	 */
+	if (proto != sdata->control_port_protocol &&
+	    proto != cpu_to_be16(ETH_P_PREAUTH))
+		return -EINVAL;
+
+	if (unencrypted)
+		flags = IEEE80211_TX_INTFL_DONT_ENCRYPT;
+	else
+		flags = 0;
+
+	skb = dev_alloc_skb(local->hw.extra_tx_headroom +
+			    sizeof(struct ethhdr) + len);
+	if (!skb)
+		return -ENOMEM;
+
+	skb_reserve(skb, local->hw.extra_tx_headroom + sizeof(struct ethhdr));
+
+	skb_put_data(skb, buf, len);
+
+	ehdr = skb_push(skb, sizeof(struct ethhdr));
+	memcpy(ehdr->h_dest, dest, ETH_ALEN);
+	memcpy(ehdr->h_source, sdata->vif.addr, ETH_ALEN);
+	ehdr->h_proto = proto;
+
+	skb->dev = dev;
+	skb->protocol = htons(ETH_P_802_3);
+	skb_reset_network_header(skb);
+	skb_reset_mac_header(skb);
+
+	__ieee80211_subif_start_xmit(skb, skb->dev, flags);
+
+	return 0;
+}