cfg80211: allow sending vendor events unicast

Sometimes, we may want to transport higher bandwidth data
through vendor events, and in that case sending it multicast
is a bad idea. Allow vendor events to be unicast.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 47 insertions, 2 deletions

diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index 7a29b709077f..bb307a11ee63 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -5854,6 +5854,7 @@ struct sk_buff *__cfg80211_alloc_event_skb(struct wiphy *wiphy,
 					   struct wireless_dev *wdev,
 					   enum nl80211_commands cmd,
 					   enum nl80211_attrs attr,
+					   unsigned int portid,
 					   int vendor_event_idx,
 					   int approxlen, gfp_t gfp);
 
@@ -5904,6 +5905,15 @@ cfg80211_vendor_cmd_alloc_reply_skb(struct wiphy *wiphy, int approxlen)
 int cfg80211_vendor_cmd_reply(struct sk_buff *skb);
 
 /**
+ * cfg80211_vendor_cmd_get_sender
+ * @wiphy: the wiphy
+ *
+ * Return the current netlink port ID in a vendor command handler.
+ * Valid to call only there.
+ */
+unsigned int cfg80211_vendor_cmd_get_sender(struct wiphy *wiphy);
+
+/**
  * cfg80211_vendor_event_alloc - allocate vendor-specific event skb
  * @wiphy: the wiphy
  * @wdev: the wireless device
@@ -5930,7 +5940,42 @@ cfg80211_vendor_event_alloc(struct wiphy *wiphy, struct wireless_dev *wdev,
 {
 	return __cfg80211_alloc_event_skb(wiphy, wdev, NL80211_CMD_VENDOR,
 					  NL80211_ATTR_VENDOR_DATA,
-					  event_idx, approxlen, gfp);
+					  0, event_idx, approxlen, gfp);
+}
+
+/**
+ * cfg80211_vendor_event_alloc_ucast - alloc unicast vendor-specific event skb
+ * @wiphy: the wiphy
+ * @wdev: the wireless device
+ * @event_idx: index of the vendor event in the wiphy's vendor_events
+ * @portid: port ID of the receiver
+ * @approxlen: an upper bound of the length of the data that will
+ *	be put into the skb
+ * @gfp: allocation flags
+ *
+ * This function allocates and pre-fills an skb for an event to send to
+ * a specific (userland) socket. This socket would previously have been
+ * obtained by cfg80211_vendor_cmd_get_sender(), and the caller MUST take
+ * care to register a netlink notifier to see when the socket closes.
+ *
+ * If wdev != NULL, both the ifindex and identifier of the specified
+ * wireless device are added to the event message before the vendor data
+ * attribute.
+ *
+ * When done filling the skb, call cfg80211_vendor_event() with the
+ * skb to send the event.
+ *
+ * Return: An allocated and pre-filled skb. %NULL if any errors happen.
+ */
+static inline struct sk_buff *
+cfg80211_vendor_event_alloc_ucast(struct wiphy *wiphy,
+				  struct wireless_dev *wdev,
+				  unsigned int portid, int approxlen,
+				  int event_idx, gfp_t gfp)
+{
+	return __cfg80211_alloc_event_skb(wiphy, wdev, NL80211_CMD_VENDOR,
+					  NL80211_ATTR_VENDOR_DATA,
+					  portid, event_idx, approxlen, gfp);
 }
 
 /**
@@ -6030,7 +6075,7 @@ static inline struct sk_buff *
 cfg80211_testmode_alloc_event_skb(struct wiphy *wiphy, int approxlen, gfp_t gfp)
 {
 	return __cfg80211_alloc_event_skb(wiphy, NULL, NL80211_CMD_TESTMODE,
-					  NL80211_ATTR_TESTDATA, -1,
+					  NL80211_ATTR_TESTDATA, 0, -1,
 					  approxlen, gfp);
 }