nl80211: Add roaming policy update using QCA vendor command

This allows updating roaming policy for drivers that select the BSS
internally so that wpa_supplicant (based on bssid parameter
configuration) and the driver remain in sync.

Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>

src/common/qca-vendor.h

@@ -32,6 +32,13 @@ enum qca_radiotap_vendor_ids {
  *
  * @QCA_NL80211_VENDOR_SUBCMD_TEST: Test command/event
  *
+ * @QCA_NL80211_VENDOR_SUBCMD_ROAMING: Set roaming policy for drivers that use
+ *	internal BSS-selection. This command uses
+ *	@QCA_WLAN_VENDOR_ATTR_ROAMING_POLICY to specify the new roaming policy
+ *	for the current connection (i.e., changes policy set by the nl80211
+ *	Connect command). @QCA_WLAN_VENDOR_ATTR_MAC_ADDR may optionally be
+ *	included to indicate which BSS to use in case roaming is disabled.
+ *
  * @QCA_NL80211_VENDOR_SUBCMD_AVOID_FREQUENCY: Recommendation of frequency
  *	ranges to avoid to reduce issues due to interference or internal
  *	co-existence information in the driver. The event data structure is
@@ -47,7 +54,8 @@ enum qca_radiotap_vendor_ids {
 enum qca_nl80211_vendor_subcmds {
 	QCA_NL80211_VENDOR_SUBCMD_UNSPEC = 0,
 	QCA_NL80211_VENDOR_SUBCMD_TEST = 1,
-	/* subcmds 2..9 not yet allocated */
+	/* subcmds 2..8 not yet allocated */
+	QCA_NL80211_VENDOR_SUBCMD_ROAMING = 9,
 	QCA_NL80211_VENDOR_SUBCMD_AVOID_FREQUENCY = 10,
 	QCA_NL80211_VENDOR_SUBCMD_DFS_CAPABILITY =  11,
 	QCA_NL80211_VENDOR_SUBCMD_NAN =  12,
@@ -66,9 +74,19 @@ enum qca_wlan_vendor_attr {
 	QCA_WLAN_VENDOR_ATTR_STATS_EXT     = 3,
 	/* used by QCA_NL80211_VENDOR_SUBCMD_STATS_EXT */
 	QCA_WLAN_VENDOR_ATTR_IFINDEX     = 4,
+	/* used by QCA_NL80211_VENDOR_SUBCMD_ROAMING, u32 with values defined
+	 * by enum qca_roaming_policy. */
+	QCA_WLAN_VENDOR_ATTR_ROAMING_POLICY = 5,
+	QCA_WLAN_VENDOR_ATTR_MAC_ADDR = 6,
 	/* keep last */
 	QCA_WLAN_VENDOR_ATTR_AFTER_LAST,
 	QCA_WLAN_VENDOR_ATTR_MAX	= QCA_WLAN_VENDOR_ATTR_AFTER_LAST - 1,
 };
 
+
+enum qca_roaming_policy {
+	QCA_ROAMING_NOT_ALLOWED,
+	QCA_ROAMING_ALLOWED_WITHIN_ESS,
+};
+
 #endif /* QCA_VENDOR_H */

src/drivers/driver_nl80211.c

@@ -307,6 +307,7 @@ struct wpa_driver_nl80211_data {
 	unsigned int start_iface_up:1;
 	unsigned int test_use_roc_tx:1;
 	unsigned int ignore_deauth_event:1;
+	unsigned int roaming_vendor_cmd_avail:1;
 	unsigned int dfs_vendor_cmd_avail:1;
 	unsigned int have_low_prio_scan:1;
 
@@ -3869,9 +3870,14 @@ static int wiphy_info_handler(struct nl_msg *msg, void *arg)
 				continue;
 			}
 			vinfo = nla_data(nl);
-			if (vinfo->subcmd ==
-			    QCA_NL80211_VENDOR_SUBCMD_DFS_CAPABILITY)
+			switch (vinfo->subcmd) {
+			case QCA_NL80211_VENDOR_SUBCMD_ROAMING:
+				drv->roaming_vendor_cmd_avail = 1;
+				break;
+			case QCA_NL80211_VENDOR_SUBCMD_DFS_CAPABILITY:
 				drv->dfs_vendor_cmd_avail = 1;
+				break;
+			}
 
 			wpa_printf(MSG_DEBUG, "nl80211: Supported vendor command: vendor_id=0x%x subcmd=%u",
 				   vinfo->vendor_id, vinfo->subcmd);
@@ -12380,6 +12386,50 @@ nla_put_failure:
 }
 
 
+static int nl80211_roaming(void *priv, int allowed, const u8 *bssid)
+{
+	struct i802_bss *bss = priv;
+	struct wpa_driver_nl80211_data *drv = bss->drv;
+	struct nl_msg *msg;
+	struct nlattr *params;
+
+	wpa_printf(MSG_DEBUG, "nl80211: Roaming policy: allowed=%d", allowed);
+
+	if (!drv->roaming_vendor_cmd_avail) {
+		wpa_printf(MSG_DEBUG,
+			   "nl80211: Ignore roaming policy change since driver does not provide command for setting it");
+		return -1;
+	}
+
+	msg = nlmsg_alloc();
+	if (!msg)
+		return -ENOMEM;
+
+	nl80211_cmd(drv, msg, 0, NL80211_CMD_VENDOR);
+
+	NLA_PUT_U32(msg, NL80211_ATTR_IFINDEX, drv->ifindex);
+	NLA_PUT_U32(msg, NL80211_ATTR_VENDOR_ID, OUI_QCA);
+	NLA_PUT_U32(msg, NL80211_ATTR_VENDOR_SUBCMD,
+		    QCA_NL80211_VENDOR_SUBCMD_ROAMING);
+
+	params = nla_nest_start(msg, NL80211_ATTR_VENDOR_DATA);
+	if (!params)
+		goto nla_put_failure;
+	NLA_PUT_U32(msg, QCA_WLAN_VENDOR_ATTR_ROAMING_POLICY,
+		    allowed ? QCA_ROAMING_ALLOWED_WITHIN_ESS :
+		    QCA_ROAMING_NOT_ALLOWED);
+	if (bssid)
+		NLA_PUT(msg, QCA_WLAN_VENDOR_ATTR_MAC_ADDR, ETH_ALEN, bssid);
+	nla_nest_end(msg, params);
+
+	return send_and_recv_msgs(drv, msg, NULL, NULL);
+
+ nla_put_failure:
+	nlmsg_free(msg);
+	return -1;
+}
+
+
 const struct wpa_driver_ops wpa_driver_nl80211_ops = {
 	.name = "nl80211",
 	.desc = "Linux nl80211/cfg80211",
@@ -12471,4 +12521,5 @@ const struct wpa_driver_ops wpa_driver_nl80211_ops = {
 	.vendor_cmd = nl80211_vendor_cmd,
 	.set_qos_map = nl80211_set_qos_map,
 	.set_wowlan = nl80211_set_wowlan,
+	.roaming = nl80211_roaming,
 };