cfg80211/mac80211: allow registering for and sending action frames

This implements a new command to register for action frames
that userspace wants to handle instead of the in-kernel
rejection. It is then responsible for rejecting ones that
it decided not to handle. There is no unregistration, but
the socket can be closed for that.

Frames that are not registered for will not be forwarded
to userspace and will be rejected by the kernel, the
cfg80211 API helps implementing that.

Additionally, this patch adds a new command that allows
doing action frame transmission from userspace. It can be
used either to exchange action frames on the current
operational channel (e.g., with the AP with which we are
currently associated) or to exchange off-channel Public
Action frames with the remain-on-channel command.

Signed-off-by: Jouni Malinen <jouni.malinen@atheros.com>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 35 insertions, 0 deletions

diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index bfc4a507001..41812a15eea 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -2084,3 +2084,38 @@ int ieee80211_mgd_disassoc(struct ieee80211_sub_if_data *sdata,
 
 	return 0;
 }
+
+int ieee80211_mgd_action(struct ieee80211_sub_if_data *sdata,
+			 struct ieee80211_channel *chan,
+			 enum nl80211_channel_type channel_type,
+			 const u8 *buf, size_t len, u64 *cookie)
+{
+	struct ieee80211_local *local = sdata->local;
+	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
+	struct sk_buff *skb;
+
+	/* Check that we are on the requested channel for transmission */
+	if ((chan != local->tmp_channel ||
+	     channel_type != local->tmp_channel_type) &&
+	    (chan != local->oper_channel ||
+	     channel_type != local->oper_channel_type))
+		return -EBUSY;
+
+	skb = dev_alloc_skb(local->hw.extra_tx_headroom + len);
+	if (!skb)
+		return -ENOMEM;
+	skb_reserve(skb, local->hw.extra_tx_headroom);
+
+	memcpy(skb_put(skb, len), buf, len);
+
+	if (!(ifmgd->flags & IEEE80211_STA_MFP_ENABLED))
+		IEEE80211_SKB_CB(skb)->flags |=
+			IEEE80211_TX_INTFL_DONT_ENCRYPT;
+	IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_NL80211_FRAME_TX |
+		IEEE80211_TX_CTL_REQ_TX_STATUS;
+	skb->dev = sdata->dev;
+	ieee80211_tx_skb(sdata, skb);
+
+	*cookie = (unsigned long) skb;
+	return 0;
+}