cfg80211/nl80211: scanning (and mac80211 update to use it)

This patch adds basic scan capability to cfg80211/nl80211 and
changes mac80211 to use it. The BSS list that cfg80211 maintains
is made driver-accessible with a private area in each BSS struct,
but mac80211 doesn't yet use it. That's another large project.

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

3 files changed, 138 insertions, 2 deletions

diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index dd1fd51638f..09a0b268e5c 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -4,6 +4,10 @@
 #include <linux/netlink.h>
 #include <linux/skbuff.h>
 #include <linux/nl80211.h>
+#include <linux/if_ether.h>
+#include <linux/ieee80211.h>
+#include <linux/wireless.h>
+#include <net/iw_handler.h>
 #include <net/genetlink.h>
 /* remove once we remove the wext stuff */
 #include <net/iw_handler.h>
@@ -505,6 +509,83 @@ struct wiphy;
 struct ieee80211_channel;
 
 /**
+ * struct cfg80211_ssid - SSID description
+ * @ssid: the SSID
+ * @ssid_len: length of the ssid
+ */
+struct cfg80211_ssid {
+	u8 ssid[IEEE80211_MAX_SSID_LEN];
+	u8 ssid_len;
+};
+
+/**
+ * struct cfg80211_scan_request - scan request description
+ *
+ * @ssids: SSIDs to scan for (active scan only)
+ * @n_ssids: number of SSIDs
+ * @channels: channels to scan on.
+ * @n_channels: number of channels for each band
+ * @wiphy: the wiphy this was for
+ * @ifidx: the interface index
+ */
+struct cfg80211_scan_request {
+	struct cfg80211_ssid *ssids;
+	int n_ssids;
+	struct ieee80211_channel **channels;
+	u32 n_channels;
+
+	/* internal */
+	struct wiphy *wiphy;
+	int ifidx;
+};
+
+/**
+ * enum cfg80211_signal_type - signal type
+ *
+ * @CFG80211_SIGNAL_TYPE_NONE: no signal strength information available
+ * @CFG80211_SIGNAL_TYPE_MBM: signal strength in mBm (100*dBm)
+ * @CFG80211_SIGNAL_TYPE_UNSPEC: signal strength, increasing from 0 through 100
+ */
+enum cfg80211_signal_type {
+	CFG80211_SIGNAL_TYPE_NONE,
+	CFG80211_SIGNAL_TYPE_MBM,
+	CFG80211_SIGNAL_TYPE_UNSPEC,
+};
+
+/**
+ * struct cfg80211_bss - BSS description
+ *
+ * This structure describes a BSS (which may also be a mesh network)
+ * for use in scan results and similar.
+ *
+ * @bssid: BSSID of the BSS
+ * @tsf: timestamp of last received update
+ * @beacon_interval: the beacon interval as from the frame
+ * @capability: the capability field in host byte order
+ * @information_elements: the information elements (Note that there
+ *	is no guarantee that these are well-formed!)
+ * @len_information_elements: total length of the information elements
+ * @signal: signal strength value
+ * @signal_type: signal type
+ * @priv: private area for driver use, has at least wiphy->bss_priv_size bytes
+ */
+struct cfg80211_bss {
+	struct ieee80211_channel *channel;
+
+	u8 bssid[ETH_ALEN];
+	u64 tsf;
+	u16 beacon_interval;
+	u16 capability;
+	u8 *information_elements;
+	size_t len_information_elements;
+
+	s32 signal;
+	enum cfg80211_signal_type signal_type;
+
+	u8 priv[0] __attribute__((__aligned__(sizeof(void *))));
+};
+
+/**
  * struct cfg80211_ops - backend description for wireless configuration
  *
  * This struct is registered by fullmac card drivers and/or wireless stacks
@@ -571,6 +652,11 @@ struct ieee80211_channel;
  * @set_channel: Set channel
  *
  * @set_mgmt_extra_ie: Set extra IE data for management frames
+ *
+ * @scan: Request to do a scan. If returning zero, the scan request is given
+ *	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.
  */
 struct cfg80211_ops {
 	int	(*suspend)(struct wiphy *wiphy);
@@ -648,6 +734,9 @@ struct cfg80211_ops {
 	int	(*set_mgmt_extra_ie)(struct wiphy *wiphy,
 				     struct net_device *dev,
 				     struct mgmt_extra_ie_params *params);
+
+	int	(*scan)(struct wiphy *wiphy, struct net_device *dev,
+			struct cfg80211_scan_request *request);
 };
 
 /* temporary wext handlers */
@@ -658,5 +747,47 @@ int cfg80211_wext_siwmode(struct net_device *dev, struct iw_request_info *info,
 			  u32 *mode, char *extra);
 int cfg80211_wext_giwmode(struct net_device *dev, struct iw_request_info *info,
 			  u32 *mode, char *extra);
+int cfg80211_wext_siwscan(struct net_device *dev,
+			  struct iw_request_info *info,
+			  union iwreq_data *wrqu, char *extra);
+int cfg80211_wext_giwscan(struct net_device *dev,
+			  struct iw_request_info *info,
+			  struct iw_point *data, char *extra);
+
+/**
+ * cfg80211_scan_done - notify that scan finished
+ *
+ * @request: the corresponding scan request
+ * @aborted: set to true if the scan was aborted for any reason,
+ *	userspace will be notified of that
+ */
+void cfg80211_scan_done(struct cfg80211_scan_request *request, bool aborted);
+
+/**
+ * cfg80211_inform_bss - inform cfg80211 of a new BSS
+ *
+ * @wiphy: the wiphy reporting the BSS
+ * @bss: the found BSS
+ * @gfp: context flags
+ *
+ * This informs cfg80211 that BSS information was found and
+ * the BSS should be updated/added.
+ */
+struct cfg80211_bss*
+cfg80211_inform_bss_frame(struct wiphy *wiphy,
+			  struct ieee80211_channel *channel,
+			  struct ieee80211_mgmt *mgmt, size_t len,
+			  s32 signal, enum cfg80211_signal_type sigtype,
+			  gfp_t gfp);
+
+struct cfg80211_bss *cfg80211_get_bss(struct wiphy *wiphy,
+				      struct ieee80211_channel *channel,
+				      const u8 *bssid,
+				      const u8 *ssid, size_t ssid_len);
+struct cfg80211_bss *cfg80211_get_mesh(struct wiphy *wiphy,
+				       struct ieee80211_channel *channel,
+				       const u8 *meshid, size_t meshidlen,
+				       const u8 *meshcfg);
+void cfg80211_put_bss(struct cfg80211_bss *bss);
 
 #endif /* __NET_CFG80211_H */
diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index 341f3e595eb..88fa3e03e3e 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -1406,7 +1406,8 @@ struct ieee80211_ops {
 	void (*update_tkip_key)(struct ieee80211_hw *hw,
 			struct ieee80211_key_conf *conf, const u8 *address,
 			u32 iv32, u16 *phase1key);
-	int (*hw_scan)(struct ieee80211_hw *hw, u8 *ssid, size_t len);
+	int (*hw_scan)(struct ieee80211_hw *hw,
+		       struct cfg80211_scan_request *req);
 	int (*get_stats)(struct ieee80211_hw *hw,
 			 struct ieee80211_low_level_stats *stats);
 	void (*get_tkip_seq)(struct ieee80211_hw *hw, u8 hw_key_idx,
@@ -1844,8 +1845,9 @@ void ieee80211_wake_queues(struct ieee80211_hw *hw);
  * mac80211 that the scan finished.
  *
  * @hw: the hardware that finished the scan
+ * @aborted: set to true if scan was aborted
  */
-void ieee80211_scan_completed(struct ieee80211_hw *hw);
+void ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted);
 
 /**
  * ieee80211_iterate_active_interfaces - iterate active interfaces
diff --git a/include/net/wireless.h b/include/net/wireless.h
index a42c1562d52..1c6285eb166 100644
--- a/include/net/wireless.h
+++ b/include/net/wireless.h
@@ -213,6 +213,9 @@ struct wiphy {
 	bool custom_regulatory;
 	bool strict_regulatory;
 
+	int bss_priv_size;
+	u8 max_scan_ssids;
+
 	/* If multiple wiphys are registered and you're handed e.g.
 	 * a regular netdev with assigned ieee80211_ptr, you won't
 	 * know whether it points to a wiphy your driver has registered