qtnfmac: enable WPA3 SAE support

In the case of SAE AP, drivers offload authentication to user-space
software, e.g. hostapd. For FullMAC drivers the procedure is as follows.
If auth_type is SAE and user space indicates external authentication
capability, then driver requests authentication offload to user-space
software using cfg80211_external_auth_request call. From that point,
auth frame exchange is performed transparently for driver: user-space
software sends/receives mgmt frames using mgmt_tx/mgmt_frame_register
cfg80211 callbacks. As soon as authenitcation is completed, user-space
software notifies driver about its status using external_auth cfg80211
callback.
Signed-off-by: Sergey Matyukevich <sergey.matyukevich.os@quantenna.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

drivers/net/wireless/quantenna/qtnfmac/cfg80211.c

@@ -53,9 +53,11 @@ static const u32 qtnf_cipher_suites[] = {
 static const struct ieee80211_txrx_stypes
 qtnf_mgmt_stypes[NUM_NL80211_IFTYPES] = {
 	[NL80211_IFTYPE_STATION] = {
-		.tx = BIT(IEEE80211_STYPE_ACTION >> 4),
+		.tx = BIT(IEEE80211_STYPE_ACTION >> 4) |
+		      BIT(IEEE80211_STYPE_AUTH >> 4),
 		.rx = BIT(IEEE80211_STYPE_ACTION >> 4) |
-		      BIT(IEEE80211_STYPE_PROBE_REQ >> 4),
+		      BIT(IEEE80211_STYPE_PROBE_REQ >> 4) |
+		      BIT(IEEE80211_STYPE_AUTH >> 4),
 	},
 	[NL80211_IFTYPE_AP] = {
 		.tx = BIT(IEEE80211_STYPE_ACTION >> 4),
@@ -636,6 +638,12 @@ qtnf_connect(struct wiphy *wiphy, struct net_device *dev,
 	if (vif->wdev.iftype != NL80211_IFTYPE_STATION)
 		return -EOPNOTSUPP;
 
+	if (sme->auth_type == NL80211_AUTHTYPE_SAE &&
+	    !(sme->flags & CONNECT_REQ_EXTERNAL_AUTH_SUPPORT)) {
+		pr_err("can not offload authentication to userspace\n");
+		return -EOPNOTSUPP;
+	}
+
 	if (sme->bssid)
 		ether_addr_copy(vif->bssid, sme->bssid);
 	else
@@ -652,6 +660,30 @@ qtnf_connect(struct wiphy *wiphy, struct net_device *dev,
 	return ret;
 }
 
+static int
+qtnf_external_auth(struct wiphy *wiphy, struct net_device *dev,
+		   struct cfg80211_external_auth_params *auth)
+{
+	struct qtnf_vif *vif = qtnf_netdev_get_priv(dev);
+	int ret;
+
+	if (vif->wdev.iftype != NL80211_IFTYPE_STATION)
+		return -EOPNOTSUPP;
+
+	if (!ether_addr_equal(vif->bssid, auth->bssid))
+		pr_warn("unexpected bssid: %pM", auth->bssid);
+
+	ret = qtnf_cmd_send_external_auth(vif, auth);
+	if (ret) {
+		pr_err("VIF%u.%u: failed to report external auth\n",
+		       vif->mac->macid, vif->vifid);
+		goto out;
+	}
+
+out:
+	return ret;
+}
+
 static int
 qtnf_disconnect(struct wiphy *wiphy, struct net_device *dev,
 		u16 reason_code)
@@ -946,6 +978,7 @@ static struct cfg80211_ops qtn_cfg80211_ops = {
 	.set_default_mgmt_key	= qtnf_set_default_mgmt_key,
 	.scan			= qtnf_scan,
 	.connect		= qtnf_connect,
+	.external_auth		= qtnf_external_auth,
 	.disconnect		= qtnf_disconnect,
 	.dump_survey		= qtnf_dump_survey,
 	.get_channel		= qtnf_get_channel,
@@ -1125,6 +1158,9 @@ int qtnf_wiphy_register(struct qtnf_hw_info *hw_info, struct qtnf_wmac *mac)
 	if (!(hw_info->hw_capab & QLINK_HW_CAPAB_OBSS_SCAN))
 		wiphy->features |= NL80211_FEATURE_NEED_OBSS_SCAN;
 
+	if (hw_info->hw_capab & QLINK_HW_CAPAB_SAE)
+		wiphy->features |= NL80211_FEATURE_SAE;
+
 #ifdef CONFIG_PM
 	if (macinfo->wowlan)
 		wiphy->wowlan = macinfo->wowlan;

drivers/net/wireless/quantenna/qtnfmac/commands.c

@@ -2322,6 +2322,35 @@ int qtnf_cmd_send_connect(struct qtnf_vif *vif,
 	return ret;
 }
 
+int qtnf_cmd_send_external_auth(struct qtnf_vif *vif,
+				struct cfg80211_external_auth_params *auth)
+{
+	struct sk_buff *cmd_skb;
+	struct qlink_cmd_external_auth *cmd;
+	int ret;
+
+	cmd_skb = qtnf_cmd_alloc_new_cmdskb(vif->mac->macid, vif->vifid,
+					    QLINK_CMD_EXTERNAL_AUTH,
+					    sizeof(*cmd));
+	if (!cmd_skb)
+		return -ENOMEM;
+
+	cmd = (struct qlink_cmd_external_auth *)cmd_skb->data;
+
+	ether_addr_copy(cmd->bssid, auth->bssid);
+	cmd->status = cpu_to_le16(auth->status);
+
+	qtnf_bus_lock(vif->mac->bus);
+	ret = qtnf_cmd_send(vif->mac->bus, cmd_skb);
+	if (ret)
+		goto out;
+
+out:
+	qtnf_bus_unlock(vif->mac->bus);
+
+	return ret;
+}
+
 int qtnf_cmd_send_disconnect(struct qtnf_vif *vif, u16 reason_code)
 {
 	struct sk_buff *cmd_skb;

drivers/net/wireless/quantenna/qtnfmac/commands.h

@@ -51,6 +51,8 @@ int qtnf_cmd_send_del_sta(struct qtnf_vif *vif,
 int qtnf_cmd_send_scan(struct qtnf_wmac *mac);
 int qtnf_cmd_send_connect(struct qtnf_vif *vif,
 			  struct cfg80211_connect_params *sme);
+int qtnf_cmd_send_external_auth(struct qtnf_vif *vif,
+				struct cfg80211_external_auth_params *auth);
 int qtnf_cmd_send_disconnect(struct qtnf_vif *vif,
 			     u16 reason_code);
 int qtnf_cmd_send_updown_intf(struct qtnf_vif *vif,

drivers/net/wireless/quantenna/qtnfmac/event.c

@@ -574,6 +574,43 @@ static int qtnf_event_handle_radar(struct qtnf_vif *vif,
 	return 0;
 }
 
+static int
+qtnf_event_handle_external_auth(struct qtnf_vif *vif,
+				const struct qlink_event_external_auth *ev,
+				u16 len)
+{
+	struct cfg80211_external_auth_params auth = {0};
+	struct wiphy *wiphy = priv_to_wiphy(vif->mac);
+	int ret;
+
+	if (len < sizeof(*ev)) {
+		pr_err("MAC%u: payload is too short\n", vif->mac->macid);
+		return -EINVAL;
+	}
+
+	if (!wiphy->registered || !vif->netdev)
+		return 0;
+
+	if (ev->ssid_len) {
+		memcpy(auth.ssid.ssid, ev->ssid, ev->ssid_len);
+		auth.ssid.ssid_len = ev->ssid_len;
+	}
+
+	auth.key_mgmt_suite = le32_to_cpu(ev->akm_suite);
+	ether_addr_copy(auth.bssid, ev->bssid);
+	auth.action = ev->action;
+
+	pr_info("%s: external auth bss=%pM action=%u akm=%u\n",
+		vif->netdev->name, auth.bssid, auth.action,
+		auth.key_mgmt_suite);
+
+	ret = cfg80211_external_auth_request(vif->netdev, &auth, GFP_KERNEL);
+	if (ret)
+		pr_warn("failed to offload external auth request\n");
+
+	return ret;
+}
+
 static int qtnf_event_parse(struct qtnf_wmac *mac,
 			    const struct sk_buff *event_skb)
 {
@@ -632,6 +669,10 @@ static int qtnf_event_parse(struct qtnf_wmac *mac,
 		ret = qtnf_event_handle_radar(vif, (const void *)event,
 					      event_len);
 		break;
+	case QLINK_EVENT_EXTERNAL_AUTH:
+		ret = qtnf_event_handle_external_auth(vif, (const void *)event,
+						      event_len);
+		break;
 	default:
 		pr_warn("unknown event type: %x\n", event_id);
 		break;

drivers/net/wireless/quantenna/qtnfmac/qlink.h

@@ -68,6 +68,7 @@ enum qlink_hw_capab {
 	QLINK_HW_CAPAB_PWR_MGMT			= BIT(4),
 	QLINK_HW_CAPAB_OBSS_SCAN		= BIT(5),
 	QLINK_HW_CAPAB_SCAN_DWELL		= BIT(6),
+	QLINK_HW_CAPAB_SAE			= BIT(8),
 };
 
 enum qlink_iface_type {
@@ -250,6 +251,7 @@ enum qlink_cmd_type {
 	QLINK_CMD_DISCONNECT		= 0x0061,
 	QLINK_CMD_PM_SET		= 0x0062,
 	QLINK_CMD_WOWLAN_SET		= 0x0063,
+	QLINK_CMD_EXTERNAL_AUTH		= 0x0066,
 };
 
 /**
@@ -480,6 +482,20 @@ struct qlink_cmd_connect {
 	u8 payload[0];
 } __packed;
 
+/**
+ * struct qlink_cmd_external_auth - data for QLINK_CMD_EXTERNAL_AUTH command
+ *
+ * @bssid: BSSID of the BSS to connect to
+ * @status: authentication status code
+ * @payload: variable portion of connection request.
+ */
+struct qlink_cmd_external_auth {
+	struct qlink_cmd chdr;
+	u8 bssid[ETH_ALEN];
+	__le16 status;
+	u8 payload[0];
+} __packed;
+
 /**
  * struct qlink_cmd_disconnect - data for QLINK_CMD_DISCONNECT command
  *
@@ -925,6 +941,7 @@ enum qlink_event_type {
 	QLINK_EVENT_BSS_LEAVE		= 0x0027,
 	QLINK_EVENT_FREQ_CHANGE		= 0x0028,
 	QLINK_EVENT_RADAR		= 0x0029,
+	QLINK_EVENT_EXTERNAL_AUTH	= 0x0030,
 };
 
 /**
@@ -1100,6 +1117,24 @@ struct qlink_event_radar {
 	u8 rsvd[3];
 } __packed;
 
+/**
+ * struct qlink_event_external_auth - data for QLINK_EVENT_EXTERNAL_AUTH event
+ *
+ * @ssid: SSID announced by BSS
+ * @ssid_len: SSID length
+ * @bssid: BSSID of the BSS to connect to
+ * @akm_suite: AKM suite for external authentication
+ * @action: action type/trigger for external authentication
+ */
+struct qlink_event_external_auth {
+	struct qlink_event ehdr;
+	u8 ssid[IEEE80211_MAX_SSID_LEN];
+	u8 ssid_len;
+	u8 bssid[ETH_ALEN];
+	__le32 akm_suite;
+	u8 action;
+} __packed;
+
 /* QLINK TLVs (Type-Length Values) definitions
  */