nl80211: Add MLME primitives to support external SME

This patch adds new nl80211 commands to allow user space to request
authentication and association (and also deauthentication and
disassociation). The commands are structured to allow separate
authentication and association steps, i.e., the interface between
kernel and user space is similar to the MLME SAP interface in IEEE
802.11 standard and an user space application takes the role of the
SME.

The patch introduces MLME-AUTHENTICATE.request,
MLME-{,RE}ASSOCIATE.request, MLME-DEAUTHENTICATE.request, and
MLME-DISASSOCIATE.request primitives. The authentication and
association commands request the actual operations in two steps
(assuming the driver supports this; if not, separate authentication
step is skipped; this could end up being a separate "connect"
command).

The initial implementation for mac80211 uses the current
net/mac80211/mlme.c for actual sending and processing of management
frames and the new nl80211 commands will just stop the current state
machine from moving automatically from authentication to association.
Future cleanup may move more of the MLME operations into cfg80211.

The goal of this design is to provide more control of authentication and
association process to user space without having to move the full MLME
implementation. This should be enough to allow IEEE 802.11r FT protocol
and 802.11s SAE authentication to be implemented. Obviously, this will
also bring the extra benefit of not having to use WEXT for association
requests with mac80211. An example implementation of a user space SME
using the new nl80211 commands is available for wpa_supplicant.

This patch is enough to get IEEE 802.11r FT protocol working with
over-the-air mechanism (over-the-DS will need additional MLME
primitives for handling the FT Action frames).

Signed-off-by: Jouni Malinen <j@w1.fi>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 113 insertions, 0 deletions

diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index ad44016021b..0da9a55881a 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -579,6 +579,105 @@ struct cfg80211_bss {
 };
 
 /**
+ * struct cfg80211_auth_request - Authentication request data
+ *
+ * This structure provides information needed to complete IEEE 802.11
+ * authentication.
+ * NOTE: This structure will likely change when more code from mac80211 is
+ * moved into cfg80211 so that non-mac80211 drivers can benefit from it, too.
+ * Before using this in a driver that does not use mac80211, it would be better
+ * to check the status of that work and better yet, volunteer to work on it.
+ *
+ * @chan: The channel to use or %NULL if not specified (auto-select based on
+ *	scan results)
+ * @peer_addr: The address of the peer STA (AP BSSID in infrastructure case);
+ *	this field is required to be present; if the driver wants to help with
+ *	BSS selection, it should use (yet to be added) MLME event to allow user
+ *	space SME to be notified of roaming candidate, so that the SME can then
+ *	use the authentication request with the recommended BSSID and whatever
+ *	other data may be needed for authentication/association
+ * @ssid: SSID or %NULL if not yet available
+ * @ssid_len: Length of ssid in octets
+ * @auth_type: Authentication type (algorithm)
+ * @ie: Extra IEs to add to Authentication frame or %NULL
+ * @ie_len: Length of ie buffer in octets
+ */
+struct cfg80211_auth_request {
+	struct ieee80211_channel *chan;
+	u8 *peer_addr;
+	const u8 *ssid;
+	size_t ssid_len;
+	enum nl80211_auth_type auth_type;
+	const u8 *ie;
+	size_t ie_len;
+};
+
+/**
+ * struct cfg80211_assoc_request - (Re)Association request data
+ *
+ * This structure provides information needed to complete IEEE 802.11
+ * (re)association.
+ * NOTE: This structure will likely change when more code from mac80211 is
+ * moved into cfg80211 so that non-mac80211 drivers can benefit from it, too.
+ * Before using this in a driver that does not use mac80211, it would be better
+ * to check the status of that work and better yet, volunteer to work on it.
+ *
+ * @chan: The channel to use or %NULL if not specified (auto-select based on
+ *	scan results)
+ * @peer_addr: The address of the peer STA (AP BSSID); this field is required
+ *	to be present and the STA must be in State 2 (authenticated) with the
+ *	peer STA
+ * @ssid: SSID
+ * @ssid_len: Length of ssid in octets
+ * @ie: Extra IEs to add to (Re)Association Request frame or %NULL
+ * @ie_len: Length of ie buffer in octets
+ */
+struct cfg80211_assoc_request {
+	struct ieee80211_channel *chan;
+	u8 *peer_addr;
+	const u8 *ssid;
+	size_t ssid_len;
+	const u8 *ie;
+	size_t ie_len;
+};
+
+/**
+ * struct cfg80211_deauth_request - Deauthentication request data
+ *
+ * This structure provides information needed to complete IEEE 802.11
+ * deauthentication.
+ *
+ * @peer_addr: The address of the peer STA (AP BSSID); this field is required
+ *	to be present and the STA must be authenticated with the peer STA
+ * @ie: Extra IEs to add to Deauthentication frame or %NULL
+ * @ie_len: Length of ie buffer in octets
+ */
+struct cfg80211_deauth_request {
+	u8 *peer_addr;
+	u16 reason_code;
+	const u8 *ie;
+	size_t ie_len;
+};
+
+/**
+ * struct cfg80211_disassoc_request - Disassociation request data
+ *
+ * This structure provides information needed to complete IEEE 802.11
+ * disassocation.
+ *
+ * @peer_addr: The address of the peer STA (AP BSSID); this field is required
+ *	to be present and the STA must be associated with the peer STA
+ * @ie: Extra IEs to add to Disassociation frame or %NULL
+ * @ie_len: Length of ie buffer in octets
+ */
+struct cfg80211_disassoc_request {
+	u8 *peer_addr;
+	u16 reason_code;
+	const u8 *ie;
+	size_t ie_len;
+};
+
+/**
  * struct cfg80211_ops - backend description for wireless configuration
  *
  * This struct is registered by fullmac card drivers and/or wireless stacks
@@ -650,6 +749,11 @@ struct cfg80211_bss {
  *	the driver, and will be valid until passed to cfg80211_scan_done().
  *	For scan results, call cfg80211_inform_bss(); you can call this outside
  *	the scan/scan_done bracket too.
+ *
+ * @auth: Request to authenticate with the specified peer
+ * @assoc: Request to (re)associate with the specified peer
+ * @deauth: Request to deauthenticate from the specified peer
+ * @disassoc: Request to disassociate from the specified peer
  */
 struct cfg80211_ops {
 	int	(*suspend)(struct wiphy *wiphy);
@@ -730,6 +834,15 @@ struct cfg80211_ops {
 
 	int	(*scan)(struct wiphy *wiphy, struct net_device *dev,
 			struct cfg80211_scan_request *request);
+
+	int	(*auth)(struct wiphy *wiphy, struct net_device *dev,
+			struct cfg80211_auth_request *req);
+	int	(*assoc)(struct wiphy *wiphy, struct net_device *dev,
+			 struct cfg80211_assoc_request *req);
+	int	(*deauth)(struct wiphy *wiphy, struct net_device *dev,
+			  struct cfg80211_deauth_request *req);
+	int	(*disassoc)(struct wiphy *wiphy, struct net_device *dev,
+			    struct cfg80211_disassoc_request *req);
 };
 
 /* temporary wext handlers */