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>

4 files changed, 184 insertions, 11 deletions

diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index 58693e5..223e536 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -1300,6 +1300,142 @@ static int ieee80211_scan(struct wiphy *wiphy,
 	return ieee80211_request_scan(sdata, req);
 }
 
+static int ieee80211_auth(struct wiphy *wiphy, struct net_device *dev,
+			  struct cfg80211_auth_request *req)
+{
+	struct ieee80211_sub_if_data *sdata;
+
+	if (!netif_running(dev))
+		return -ENETDOWN;
+
+	sdata = IEEE80211_DEV_TO_SUB_IF(dev);
+
+	if (sdata->vif.type != NL80211_IFTYPE_STATION)
+		return -EOPNOTSUPP;
+
+	switch (req->auth_type) {
+	case NL80211_AUTHTYPE_OPEN_SYSTEM:
+		sdata->u.mgd.auth_algs = IEEE80211_AUTH_ALG_OPEN;
+		break;
+	case NL80211_AUTHTYPE_SHARED_KEY:
+		sdata->u.mgd.auth_algs = IEEE80211_AUTH_ALG_SHARED_KEY;
+		break;
+	case NL80211_AUTHTYPE_FT:
+		sdata->u.mgd.auth_algs = IEEE80211_AUTH_ALG_FT;
+		break;
+	case NL80211_AUTHTYPE_NETWORK_EAP:
+		sdata->u.mgd.auth_algs = IEEE80211_AUTH_ALG_LEAP;
+		break;
+	default:
+		return -EOPNOTSUPP;
+	}
+
+	memcpy(sdata->u.mgd.bssid, req->peer_addr, ETH_ALEN);
+	sdata->u.mgd.flags &= ~IEEE80211_STA_AUTO_BSSID_SEL;
+	sdata->u.mgd.flags |= IEEE80211_STA_BSSID_SET;
+
+	/* TODO: req->chan */
+	sdata->u.mgd.flags |= IEEE80211_STA_AUTO_CHANNEL_SEL;
+
+	if (req->ssid) {
+		sdata->u.mgd.flags |= IEEE80211_STA_SSID_SET;
+		memcpy(sdata->u.mgd.ssid, req->ssid, req->ssid_len);
+		sdata->u.mgd.ssid_len = req->ssid_len;
+		sdata->u.mgd.flags &= ~IEEE80211_STA_AUTO_SSID_SEL;
+	}
+
+	kfree(sdata->u.mgd.sme_auth_ie);
+	sdata->u.mgd.sme_auth_ie = NULL;
+	sdata->u.mgd.sme_auth_ie_len = 0;
+	if (req->ie) {
+		sdata->u.mgd.sme_auth_ie = kmalloc(req->ie_len, GFP_KERNEL);
+		if (sdata->u.mgd.sme_auth_ie == NULL)
+			return -ENOMEM;
+		memcpy(sdata->u.mgd.sme_auth_ie, req->ie, req->ie_len);
+		sdata->u.mgd.sme_auth_ie_len = req->ie_len;
+	}
+
+	sdata->u.mgd.flags |= IEEE80211_STA_EXT_SME;
+	sdata->u.mgd.state = IEEE80211_STA_MLME_DIRECT_PROBE;
+	ieee80211_sta_req_auth(sdata);
+	return 0;
+}
+
+static int ieee80211_assoc(struct wiphy *wiphy, struct net_device *dev,
+			   struct cfg80211_assoc_request *req)
+{
+	struct ieee80211_sub_if_data *sdata;
+	int ret;
+
+	if (!netif_running(dev))
+		return -ENETDOWN;
+
+	sdata = IEEE80211_DEV_TO_SUB_IF(dev);
+
+	if (sdata->vif.type != NL80211_IFTYPE_STATION)
+		return -EOPNOTSUPP;
+
+	if (memcmp(sdata->u.mgd.bssid, req->peer_addr, ETH_ALEN) != 0 ||
+	    !(sdata->u.mgd.flags & IEEE80211_STA_AUTHENTICATED))
+		return -ENOLINK; /* not authenticated */
+
+	sdata->u.mgd.flags &= ~IEEE80211_STA_AUTO_BSSID_SEL;
+	sdata->u.mgd.flags |= IEEE80211_STA_BSSID_SET;
+
+	/* TODO: req->chan */
+	sdata->u.mgd.flags |= IEEE80211_STA_AUTO_CHANNEL_SEL;
+
+	if (req->ssid) {
+		sdata->u.mgd.flags |= IEEE80211_STA_SSID_SET;
+		memcpy(sdata->u.mgd.ssid, req->ssid, req->ssid_len);
+		sdata->u.mgd.ssid_len = req->ssid_len;
+		sdata->u.mgd.flags &= ~IEEE80211_STA_AUTO_SSID_SEL;
+	} else
+		sdata->u.mgd.flags |= IEEE80211_STA_AUTO_SSID_SEL;
+
+	ret = ieee80211_sta_set_extra_ie(sdata, req->ie, req->ie_len);
+	if (ret)
+		return ret;
+
+	sdata->u.mgd.flags |= IEEE80211_STA_EXT_SME;
+	sdata->u.mgd.state = IEEE80211_STA_MLME_ASSOCIATE;
+	ieee80211_sta_req_auth(sdata);
+	return 0;
+}
+
+static int ieee80211_deauth(struct wiphy *wiphy, struct net_device *dev,
+			    struct cfg80211_deauth_request *req)
+{
+	struct ieee80211_sub_if_data *sdata;
+
+	if (!netif_running(dev))
+		return -ENETDOWN;
+
+	sdata = IEEE80211_DEV_TO_SUB_IF(dev);
+	if (sdata->vif.type != NL80211_IFTYPE_STATION)
+		return -EOPNOTSUPP;
+
+	/* TODO: req->ie */
+	return ieee80211_sta_deauthenticate(sdata, req->reason_code);
+}
+
+static int ieee80211_disassoc(struct wiphy *wiphy, struct net_device *dev,
+			      struct cfg80211_disassoc_request *req)
+{
+	struct ieee80211_sub_if_data *sdata;
+
+	if (!netif_running(dev))
+		return -ENETDOWN;
+
+	sdata = IEEE80211_DEV_TO_SUB_IF(dev);
+
+	if (sdata->vif.type != NL80211_IFTYPE_STATION)
+		return -EOPNOTSUPP;
+
+	/* TODO: req->ie */
+	return ieee80211_sta_disassociate(sdata, req->reason_code);
+}
+
 struct cfg80211_ops mac80211_config_ops = {
 	.add_virtual_intf = ieee80211_add_iface,
 	.del_virtual_intf = ieee80211_del_iface,
@@ -1333,4 +1469,8 @@ struct cfg80211_ops mac80211_config_ops = {
 	.suspend = ieee80211_suspend,
 	.resume = ieee80211_resume,
 	.scan = ieee80211_scan,
+	.auth = ieee80211_auth,
+	.assoc = ieee80211_assoc,
+	.deauth = ieee80211_deauth,
+	.disassoc = ieee80211_disassoc,
 };
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index ad12c2a..7b96d95 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -256,6 +256,7 @@ struct mesh_preq_queue {
 #define IEEE80211_STA_TKIP_WEP_USED	BIT(14)
 #define IEEE80211_STA_CSA_RECEIVED	BIT(15)
 #define IEEE80211_STA_MFP_ENABLED	BIT(16)
+#define IEEE80211_STA_EXT_SME		BIT(17)
 /* flags for MLME request */
 #define IEEE80211_STA_REQ_SCAN 0
 #define IEEE80211_STA_REQ_DIRECT_PROBE 1
@@ -266,6 +267,7 @@ struct mesh_preq_queue {
 #define IEEE80211_AUTH_ALG_OPEN BIT(0)
 #define IEEE80211_AUTH_ALG_SHARED_KEY BIT(1)
 #define IEEE80211_AUTH_ALG_LEAP BIT(2)
+#define IEEE80211_AUTH_ALG_FT BIT(3)
 
 struct ieee80211_if_managed {
 	struct timer_list timer;
@@ -335,6 +337,9 @@ struct ieee80211_if_managed {
 	size_t ie_deauth_len;
 	u8 *ie_disassoc;
 	size_t ie_disassoc_len;
+
+	u8 *sme_auth_ie;
+	size_t sme_auth_ie_len;
 };
 
 enum ieee80211_ibss_flags {
@@ -970,7 +975,7 @@ ieee80211_scan_rx(struct ieee80211_sub_if_data *sdata,
 		  struct sk_buff *skb,
 		  struct ieee80211_rx_status *rx_status);
 int ieee80211_sta_set_extra_ie(struct ieee80211_sub_if_data *sdata,
-			       char *ie, size_t len);
+			       const char *ie, size_t len);
 
 void ieee80211_mlme_notify_scan_completed(struct ieee80211_local *local);
 void ieee80211_scan_failed(struct ieee80211_local *local);
diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index 6dc7a61..d1bcc84 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -730,6 +730,8 @@ static void ieee80211_authenticate(struct ieee80211_sub_if_data *sdata)
 {
 	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
 	struct ieee80211_local *local = sdata->local;
+	u8 *ies;
+	size_t ies_len;
 
 	ifmgd->auth_tries++;
 	if (ifmgd->auth_tries > IEEE80211_AUTH_MAX_TRIES) {
@@ -755,7 +757,14 @@ static void ieee80211_authenticate(struct ieee80211_sub_if_data *sdata)
 	printk(KERN_DEBUG "%s: authenticate with AP %pM\n",
 	       sdata->dev->name, ifmgd->bssid);
 
-	ieee80211_send_auth(sdata, 1, ifmgd->auth_alg, NULL, 0,
+	if (ifmgd->flags & IEEE80211_STA_EXT_SME) {
+		ies = ifmgd->sme_auth_ie;
+		ies_len = ifmgd->sme_auth_ie_len;
+	} else {
+		ies = NULL;
+		ies_len = 0;
+	}
+	ieee80211_send_auth(sdata, 1, ifmgd->auth_alg, ies, ies_len,
 			    ifmgd->bssid, 0);
 	ifmgd->auth_transaction = 2;
 
@@ -870,7 +879,8 @@ static int ieee80211_privacy_mismatch(struct ieee80211_sub_if_data *sdata)
 	int wep_privacy;
 	int privacy_invoked;
 
-	if (!ifmgd || (ifmgd->flags & IEEE80211_STA_MIXED_CELL))
+	if (!ifmgd || (ifmgd->flags & (IEEE80211_STA_MIXED_CELL |
+				       IEEE80211_STA_EXT_SME)))
 		return 0;
 
 	bss = ieee80211_rx_bss_get(local, ifmgd->bssid,
@@ -998,7 +1008,11 @@ static void ieee80211_auth_completed(struct ieee80211_sub_if_data *sdata)
 
 	printk(KERN_DEBUG "%s: authenticated\n", sdata->dev->name);
 	ifmgd->flags |= IEEE80211_STA_AUTHENTICATED;
-	ieee80211_associate(sdata);
+	if (ifmgd->flags & IEEE80211_STA_EXT_SME) {
+		/* Wait for SME to request association */
+		ifmgd->state = IEEE80211_STA_MLME_DISABLED;
+	} else
+		ieee80211_associate(sdata);
 }
 
 
@@ -1084,6 +1098,7 @@ static void ieee80211_rx_mgmt_auth(struct ieee80211_sub_if_data *sdata,
 	switch (ifmgd->auth_alg) {
 	case WLAN_AUTH_OPEN:
 	case WLAN_AUTH_LEAP:
+	case WLAN_AUTH_FT:
 		ieee80211_auth_completed(sdata);
 		cfg80211_send_rx_auth(sdata->dev, (u8 *) mgmt, len);
 		break;
@@ -1117,9 +1132,10 @@ static void ieee80211_rx_mgmt_deauth(struct ieee80211_sub_if_data *sdata,
 		printk(KERN_DEBUG "%s: deauthenticated (Reason: %u)\n",
 				sdata->dev->name, reason_code);
 
-	if (ifmgd->state == IEEE80211_STA_MLME_AUTHENTICATE ||
-	    ifmgd->state == IEEE80211_STA_MLME_ASSOCIATE ||
-	    ifmgd->state == IEEE80211_STA_MLME_ASSOCIATED) {
+	if (!(ifmgd->flags & IEEE80211_STA_EXT_SME) &&
+	    (ifmgd->state == IEEE80211_STA_MLME_AUTHENTICATE ||
+	     ifmgd->state == IEEE80211_STA_MLME_ASSOCIATE ||
+	     ifmgd->state == IEEE80211_STA_MLME_ASSOCIATED)) {
 		ifmgd->state = IEEE80211_STA_MLME_DIRECT_PROBE;
 		mod_timer(&ifmgd->timer, jiffies +
 				      IEEE80211_RETRY_AUTH_INTERVAL);
@@ -1150,7 +1166,8 @@ static void ieee80211_rx_mgmt_disassoc(struct ieee80211_sub_if_data *sdata,
 		printk(KERN_DEBUG "%s: disassociated (Reason: %u)\n",
 				sdata->dev->name, reason_code);
 
-	if (ifmgd->state == IEEE80211_STA_MLME_ASSOCIATED) {
+	if (!(ifmgd->flags & IEEE80211_STA_EXT_SME) &&
+	    ifmgd->state == IEEE80211_STA_MLME_ASSOCIATED) {
 		ifmgd->state = IEEE80211_STA_MLME_ASSOCIATE;
 		mod_timer(&ifmgd->timer, jiffies +
 				      IEEE80211_RETRY_AUTH_INTERVAL);
@@ -1664,6 +1681,8 @@ static void ieee80211_sta_reset_auth(struct ieee80211_sub_if_data *sdata)
 		ifmgd->auth_alg = WLAN_AUTH_SHARED_KEY;
 	else if (ifmgd->auth_algs & IEEE80211_AUTH_ALG_LEAP)
 		ifmgd->auth_alg = WLAN_AUTH_LEAP;
+	else if (ifmgd->auth_algs & IEEE80211_AUTH_ALG_FT)
+		ifmgd->auth_alg = WLAN_AUTH_FT;
 	else
 		ifmgd->auth_alg = WLAN_AUTH_OPEN;
 	ifmgd->auth_transaction = -1;
@@ -1687,7 +1706,8 @@ static int ieee80211_sta_config_auth(struct ieee80211_sub_if_data *sdata)
 	u16 capa_val = WLAN_CAPABILITY_ESS;
 	struct ieee80211_channel *chan = local->oper_channel;
 
-	if (ifmgd->flags & (IEEE80211_STA_AUTO_SSID_SEL |
+	if (!(ifmgd->flags & IEEE80211_STA_EXT_SME) &&
+	    ifmgd->flags & (IEEE80211_STA_AUTO_SSID_SEL |
 			    IEEE80211_STA_AUTO_BSSID_SEL |
 			    IEEE80211_STA_AUTO_CHANNEL_SEL)) {
 		capa_mask |= WLAN_CAPABILITY_PRIVACY;
@@ -1884,7 +1904,11 @@ void ieee80211_sta_req_auth(struct ieee80211_sub_if_data *sdata)
 			ieee80211_set_disassoc(sdata, true, true,
 					       WLAN_REASON_DEAUTH_LEAVING);
 
-		set_bit(IEEE80211_STA_REQ_AUTH, &ifmgd->request);
+		if (!(ifmgd->flags & IEEE80211_STA_EXT_SME) ||
+		    ifmgd->state != IEEE80211_STA_MLME_ASSOCIATE)
+			set_bit(IEEE80211_STA_REQ_AUTH, &ifmgd->request);
+		else if (ifmgd->flags & IEEE80211_STA_EXT_SME)
+			set_bit(IEEE80211_STA_REQ_RUN, &ifmgd->request);
 		queue_work(local->hw.workqueue, &ifmgd->work);
 	}
 }
@@ -1953,7 +1977,8 @@ int ieee80211_sta_set_bssid(struct ieee80211_sub_if_data *sdata, u8 *bssid)
 	return ieee80211_sta_commit(sdata);
 }
 
-int ieee80211_sta_set_extra_ie(struct ieee80211_sub_if_data *sdata, char *ie, size_t len)
+int ieee80211_sta_set_extra_ie(struct ieee80211_sub_if_data *sdata,
+			       const char *ie, size_t len)
 {
 	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
 
diff --git a/net/mac80211/wext.c b/net/mac80211/wext.c
index e55d283..ce21d66 100644
--- a/net/mac80211/wext.c
+++ b/net/mac80211/wext.c
@@ -137,6 +137,7 @@ static int ieee80211_ioctl_siwgenie(struct net_device *dev,
 		if (ret)
 			return ret;
 		sdata->u.mgd.flags &= ~IEEE80211_STA_AUTO_BSSID_SEL;
+		sdata->u.mgd.flags &= ~IEEE80211_STA_EXT_SME;
 		ieee80211_sta_req_auth(sdata);
 		return 0;
 	}
@@ -224,6 +225,7 @@ static int ieee80211_ioctl_siwessid(struct net_device *dev,
 		if (ret)
 			return ret;
 
+		sdata->u.mgd.flags &= ~IEEE80211_STA_EXT_SME;
 		ieee80211_sta_req_auth(sdata);
 		return 0;
 	} else if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
@@ -287,6 +289,7 @@ static int ieee80211_ioctl_siwap(struct net_device *dev,
 		ret = ieee80211_sta_set_bssid(sdata, (u8 *) &ap_addr->sa_data);
 		if (ret)
 			return ret;
+		sdata->u.mgd.flags &= ~IEEE80211_STA_EXT_SME;
 		ieee80211_sta_req_auth(sdata);
 		return 0;
 	} else if (sdata->vif.type == NL80211_IFTYPE_ADHOC) {