cfg80211/mac80211: extensible frame processing

Allow userspace to register for more than just
action frames by giving the frame subtype, and
make it possible to use this in various modes
as well.

With some tweaks and some added functionality
this will, in the future, also be usable in AP
mode and be able to replace the cooked monitor
interface currently used in that case.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 94 insertions, 50 deletions

diff --git a/net/wireless/mlme.c b/net/wireless/mlme.c
index ee0af32..8515b1e 100644
--- a/net/wireless/mlme.c
+++ b/net/wireless/mlme.c
@@ -748,31 +748,51 @@ void cfg80211_new_sta(struct net_device *dev, const u8 *mac_addr,
 }
 EXPORT_SYMBOL(cfg80211_new_sta);
 
-struct cfg80211_action_registration {
+struct cfg80211_mgmt_registration {
 	struct list_head list;
 
 	u32 nlpid;
 
 	int match_len;
 
+	__le16 frame_type;
+
 	u8 match[];
 };
 
-int cfg80211_mlme_register_action(struct wireless_dev *wdev, u32 snd_pid,
-				  const u8 *match_data, int match_len)
+int cfg80211_mlme_register_mgmt(struct wireless_dev *wdev, u32 snd_pid,
+				u16 frame_type, const u8 *match_data,
+				int match_len)
 {
-	struct cfg80211_action_registration *reg, *nreg;
+	struct cfg80211_mgmt_registration *reg, *nreg;
 	int err = 0;
+	u16 mgmt_type;
+
+	if (!wdev->wiphy->mgmt_stypes)
+		return -EOPNOTSUPP;
+
+	if ((frame_type & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_MGMT)
+		return -EINVAL;
+
+	if (frame_type & ~(IEEE80211_FCTL_FTYPE | IEEE80211_FCTL_STYPE))
+		return -EINVAL;
+
+	mgmt_type = (frame_type & IEEE80211_FCTL_STYPE) >> 4;
+	if (!(wdev->wiphy->mgmt_stypes[wdev->iftype].rx & BIT(mgmt_type)))
+		return -EINVAL;
 
 	nreg = kzalloc(sizeof(*reg) + match_len, GFP_KERNEL);
 	if (!nreg)
 		return -ENOMEM;
 
-	spin_lock_bh(&wdev->action_registrations_lock);
+	spin_lock_bh(&wdev->mgmt_registrations_lock);
 
-	list_for_each_entry(reg, &wdev->action_registrations, list) {
+	list_for_each_entry(reg, &wdev->mgmt_registrations, list) {
 		int mlen = min(match_len, reg->match_len);
 
+		if (frame_type != le16_to_cpu(reg->frame_type))
+			continue;
+
 		if (memcmp(reg->match, match_data, mlen) == 0) {
 			err = -EALREADY;
 			break;
@@ -787,62 +807,75 @@ int cfg80211_mlme_register_action(struct wireless_dev *wdev, u32 snd_pid,
 	memcpy(nreg->match, match_data, match_len);
 	nreg->match_len = match_len;
 	nreg->nlpid = snd_pid;
-	list_add(&nreg->list, &wdev->action_registrations);
+	nreg->frame_type = cpu_to_le16(frame_type);
+	list_add(&nreg->list, &wdev->mgmt_registrations);
 
  out:
-	spin_unlock_bh(&wdev->action_registrations_lock);
+	spin_unlock_bh(&wdev->mgmt_registrations_lock);
 	return err;
 }
 
-void cfg80211_mlme_unregister_actions(struct wireless_dev *wdev, u32 nlpid)
+void cfg80211_mlme_unregister_socket(struct wireless_dev *wdev, u32 nlpid)
 {
-	struct cfg80211_action_registration *reg, *tmp;
+	struct cfg80211_mgmt_registration *reg, *tmp;
 
-	spin_lock_bh(&wdev->action_registrations_lock);
+	spin_lock_bh(&wdev->mgmt_registrations_lock);
 
-	list_for_each_entry_safe(reg, tmp, &wdev->action_registrations, list) {
+	list_for_each_entry_safe(reg, tmp, &wdev->mgmt_registrations, list) {
 		if (reg->nlpid == nlpid) {
 			list_del(&reg->list);
 			kfree(reg);
 		}
 	}
 
-	spin_unlock_bh(&wdev->action_registrations_lock);
+	spin_unlock_bh(&wdev->mgmt_registrations_lock);
 }
 
-void cfg80211_mlme_purge_actions(struct wireless_dev *wdev)
+void cfg80211_mlme_purge_registrations(struct wireless_dev *wdev)
 {
-	struct cfg80211_action_registration *reg, *tmp;
+	struct cfg80211_mgmt_registration *reg, *tmp;
 
-	spin_lock_bh(&wdev->action_registrations_lock);
+	spin_lock_bh(&wdev->mgmt_registrations_lock);
 
-	list_for_each_entry_safe(reg, tmp, &wdev->action_registrations, list) {
+	list_for_each_entry_safe(reg, tmp, &wdev->mgmt_registrations, list) {
 		list_del(&reg->list);
 		kfree(reg);
 	}
 
-	spin_unlock_bh(&wdev->action_registrations_lock);
+	spin_unlock_bh(&wdev->mgmt_registrations_lock);
 }
 
-int cfg80211_mlme_action(struct cfg80211_registered_device *rdev,
-			 struct net_device *dev,
-			 struct ieee80211_channel *chan,
-			 enum nl80211_channel_type channel_type,
-			 bool channel_type_valid,
-			 const u8 *buf, size_t len, u64 *cookie)
+int cfg80211_mlme_mgmt_tx(struct cfg80211_registered_device *rdev,
+			  struct net_device *dev,
+			  struct ieee80211_channel *chan,
+			  enum nl80211_channel_type channel_type,
+			  bool channel_type_valid,
+			  const u8 *buf, size_t len, u64 *cookie)
 {
 	struct wireless_dev *wdev = dev->ieee80211_ptr;
 	const struct ieee80211_mgmt *mgmt;
+	u16 stype;
+
+	if (!wdev->wiphy->mgmt_stypes)
+		return -EOPNOTSUPP;
 
-	if (rdev->ops->action == NULL)
+	if (!rdev->ops->mgmt_tx)
 		return -EOPNOTSUPP;
+
 	if (len < 24 + 1)
 		return -EINVAL;
 
 	mgmt = (const struct ieee80211_mgmt *) buf;
-	if (!ieee80211_is_action(mgmt->frame_control))
+
+	if (!ieee80211_is_mgmt(mgmt->frame_control))
 		return -EINVAL;
-	if (mgmt->u.action.category != WLAN_CATEGORY_PUBLIC) {
+
+	stype = le16_to_cpu(mgmt->frame_control) & IEEE80211_FCTL_STYPE;
+	if (!(wdev->wiphy->mgmt_stypes[wdev->iftype].tx & BIT(stype >> 4)))
+		return -EINVAL;
+
+	if (ieee80211_is_action(mgmt->frame_control) &&
+	    mgmt->u.action.category != WLAN_CATEGORY_PUBLIC) {
 		/* Verify that we are associated with the destination AP */
 		wdev_lock(wdev);
 
@@ -863,64 +896,75 @@ int cfg80211_mlme_action(struct cfg80211_registered_device *rdev,
 		return -EINVAL;
 
 	/* Transmit the Action frame as requested by user space */
-	return rdev->ops->action(&rdev->wiphy, dev, chan, channel_type,
-				 channel_type_valid, buf, len, cookie);
+	return rdev->ops->mgmt_tx(&rdev->wiphy, dev, chan, channel_type,
+				  channel_type_valid, buf, len, cookie);
 }
 
-bool cfg80211_rx_action(struct net_device *dev, int freq, const u8 *buf,
-			size_t len, gfp_t gfp)
+bool cfg80211_rx_mgmt(struct net_device *dev, int freq, const u8 *buf,
+		      size_t len, gfp_t gfp)
 {
 	struct wireless_dev *wdev = dev->ieee80211_ptr;
 	struct wiphy *wiphy = wdev->wiphy;
 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
-	struct cfg80211_action_registration *reg;
-	const u8 *action_data;
-	int action_data_len;
+	struct cfg80211_mgmt_registration *reg;
+	const struct ieee80211_txrx_stypes *stypes =
+		&wiphy->mgmt_stypes[wdev->iftype];
+	struct ieee80211_mgmt *mgmt = (void *)buf;
+	const u8 *data;
+	int data_len;
 	bool result = false;
+	__le16 ftype = mgmt->frame_control &
+		cpu_to_le16(IEEE80211_FCTL_FTYPE | IEEE80211_FCTL_STYPE);
+	u16 stype;
 
-	/* frame length - min size excluding category */
-	action_data_len = len - (IEEE80211_MIN_ACTION_SIZE - 1);
+	stype = (le16_to_cpu(mgmt->frame_control) & IEEE80211_FCTL_STYPE) >> 4;
 
-	/* action data starts with category */
-	action_data = buf + IEEE80211_MIN_ACTION_SIZE - 1;
+	if (!(stypes->rx & BIT(stype)))
+		return false;
 
-	spin_lock_bh(&wdev->action_registrations_lock);
+	data = buf + ieee80211_hdrlen(mgmt->frame_control);
+	data_len = len - ieee80211_hdrlen(mgmt->frame_control);
+
+	spin_lock_bh(&wdev->mgmt_registrations_lock);
+
+	list_for_each_entry(reg, &wdev->mgmt_registrations, list) {
+		if (reg->frame_type != ftype)
+			continue;
 
-	list_for_each_entry(reg, &wdev->action_registrations, list) {
-		if (reg->match_len > action_data_len)
+		if (reg->match_len > data_len)
 			continue;
 
-		if (memcmp(reg->match, action_data, reg->match_len))
+		if (memcmp(reg->match, data, reg->match_len))
 			continue;
 
 		/* found match! */
 
 		/* Indicate the received Action frame to user space */
-		if (nl80211_send_action(rdev, dev, reg->nlpid, freq,
-					buf, len, gfp))
+		if (nl80211_send_mgmt(rdev, dev, reg->nlpid, freq,
+				      buf, len, gfp))
 			continue;
 
 		result = true;
 		break;
 	}
 
-	spin_unlock_bh(&wdev->action_registrations_lock);
+	spin_unlock_bh(&wdev->mgmt_registrations_lock);
 
 	return result;
 }
-EXPORT_SYMBOL(cfg80211_rx_action);
+EXPORT_SYMBOL(cfg80211_rx_mgmt);
 
-void cfg80211_action_tx_status(struct net_device *dev, u64 cookie,
-			       const u8 *buf, size_t len, bool ack, gfp_t gfp)
+void cfg80211_mgmt_tx_status(struct net_device *dev, u64 cookie,
+			     const u8 *buf, size_t len, bool ack, gfp_t gfp)
 {
 	struct wireless_dev *wdev = dev->ieee80211_ptr;
 	struct wiphy *wiphy = wdev->wiphy;
 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
 
 	/* Indicate TX status of the Action frame to user space */
-	nl80211_send_action_tx_status(rdev, dev, cookie, buf, len, ack, gfp);
+	nl80211_send_mgmt_tx_status(rdev, dev, cookie, buf, len, ack, gfp);
 }
-EXPORT_SYMBOL(cfg80211_action_tx_status);
+EXPORT_SYMBOL(cfg80211_mgmt_tx_status);
 
 void cfg80211_cqm_rssi_notify(struct net_device *dev,
 			      enum nl80211_cqm_rssi_threshold_event rssi_event,