Fix init of group state machine for static VLANs

This ensures that group key is set as long as the interface exists.

Additionally, ifconfig_up is needed as wpa_group will enter
FATAL_FAILURE if the interface is still down. Also vlan_remove_dynamic()
is moved after wpa_auth_sta_deinit() so vlan_remove_dynamic() can check
it was the last user of the wpa_group.

Signed-off-by: Michael Braun <michael-dev@fami-braun.de>

src/ap/sta_info.c

@@ -172,19 +172,6 @@ void ap_free_sta(struct hostapd_data *hapd, struct sta_info *sta)
 	    !(sta->flags & WLAN_STA_PREAUTH))
 		hostapd_drv_sta_remove(hapd, sta->addr);
 
-#ifndef CONFIG_NO_VLAN
-	if (sta->vlan_id_bound) {
-		/*
-		 * Need to remove the STA entry before potentially removing the
-		 * VLAN.
-		 */
-		if (hapd->iface->driver_ap_teardown &&
-		    !(sta->flags & WLAN_STA_PREAUTH))
-			hostapd_drv_sta_remove(hapd, sta->addr);
-		vlan_remove_dynamic(hapd, sta->vlan_id_bound);
-	}
-#endif /* CONFIG_NO_VLAN */
-
 	ap_sta_hash_del(hapd, sta);
 	ap_sta_list_del(hapd, sta);
 
@@ -274,6 +261,24 @@ void ap_free_sta(struct hostapd_data *hapd, struct sta_info *sta)
 		radius_client_flush_auth(hapd->radius, sta->addr);
 #endif /* CONFIG_NO_RADIUS */
 
+#ifndef CONFIG_NO_VLAN
+	/*
+	 * sta->wpa_sm->group needs to be released before so that
+	 * vlan_remove_dynamic() can check that no stations are left on the
+	 * AP_VLAN netdev.
+	 */
+	if (sta->vlan_id_bound) {
+		/*
+		 * Need to remove the STA entry before potentially removing the
+		 * VLAN.
+		 */
+		if (hapd->iface->driver_ap_teardown &&
+		    !(sta->flags & WLAN_STA_PREAUTH))
+			hostapd_drv_sta_remove(hapd, sta->addr);
+		vlan_remove_dynamic(hapd, sta->vlan_id_bound);
+	}
+#endif /* CONFIG_NO_VLAN */
+
 	os_free(sta->challenge);
 
 #ifdef CONFIG_IEEE80211W

src/ap/vlan_init.c

@@ -9,9 +9,9 @@
  */
 
 #include "utils/includes.h"
-#ifdef CONFIG_FULL_DYNAMIC_VLAN
 #include <net/if.h>
 #include <sys/ioctl.h>
+#ifdef CONFIG_FULL_DYNAMIC_VLAN
 #include <linux/sockios.h>
 #include <linux/if_vlan.h>
 #include <linux/if_bridge.h>
@@ -21,6 +21,7 @@
 #include "hostapd.h"
 #include "ap_config.h"
 #include "ap_drv_ops.h"
+#include "wpa_auth.h"
 #include "vlan_init.h"
 #include "vlan_util.h"
 
@@ -119,6 +120,8 @@ static int dyn_iface_put(struct hostapd_data *hapd, const char *ifname)
 	return clean;
 }
 
+#endif /* CONFIG_FULL_DYNAMIC_VLAN */
+
 
 static int ifconfig_helper(const char *if_name, int up)
 {
@@ -167,6 +170,58 @@ static int ifconfig_up(const char *if_name)
 }
 
 
+static int vlan_if_add(struct hostapd_data *hapd, struct hostapd_vlan *vlan,
+		       int existsok)
+{
+	int ret;
+
+	if (!if_nametoindex(vlan->ifname))
+		ret = hostapd_vlan_if_add(hapd, vlan->ifname);
+	else if (!existsok)
+		return -1;
+	else
+		ret = 0;
+
+	if (ret)
+		return ret;
+
+	ifconfig_up(vlan->ifname); /* else wpa group will fail fatal */
+
+	if (hapd->wpa_auth)
+		ret = wpa_auth_ensure_group(hapd->wpa_auth, vlan->vlan_id);
+
+	if (ret == 0)
+		return ret;
+
+	wpa_printf(MSG_ERROR, "WPA initialization for VLAN %d failed (%d)",
+		   vlan->vlan_id, ret);
+	if (wpa_auth_release_group(hapd->wpa_auth, vlan->vlan_id))
+		wpa_printf(MSG_ERROR, "WPA deinit of %s failed", vlan->ifname);
+
+	/* group state machine setup failed */
+	if (hostapd_vlan_if_remove(hapd, vlan->ifname))
+		wpa_printf(MSG_ERROR, "Removal of %s failed", vlan->ifname);
+
+	return ret;
+}
+
+
+static int vlan_if_remove(struct hostapd_data *hapd, struct hostapd_vlan *vlan)
+{
+	int ret;
+
+	ret = wpa_auth_release_group(hapd->wpa_auth, vlan->vlan_id);
+	if (ret)
+		wpa_printf(MSG_ERROR,
+			   "WPA deinitialization for VLAN %d failed (%d)",
+			   vlan->vlan_id, ret);
+
+	return hostapd_vlan_if_remove(hapd, vlan->ifname);
+}
+
+
+#ifdef CONFIG_FULL_DYNAMIC_VLAN
+
 static int ifconfig_down(const char *if_name)
 {
 	wpa_printf(MSG_DEBUG, "VLAN: Set interface %s down", if_name);
@@ -913,17 +968,14 @@ static int vlan_dynamic_add(struct hostapd_data *hapd,
 {
 	while (vlan) {
 		if (vlan->vlan_id != VLAN_ID_WILDCARD) {
-			if (hostapd_vlan_if_add(hapd, vlan->ifname)) {
-				if (errno != EEXIST) {
-					wpa_printf(MSG_ERROR, "VLAN: Could "
-						   "not add VLAN %s: %s",
-						   vlan->ifname,
-						   strerror(errno));
-					return -1;
-				}
+			if (vlan_if_add(hapd, vlan, 1)) {
+				wpa_printf(MSG_ERROR,
+					   "VLAN: Could not add VLAN %s: %s",
+					   vlan->ifname, strerror(errno));
+				return -1;
 			}
 #ifdef CONFIG_FULL_DYNAMIC_VLAN
-			ifconfig_up(vlan->ifname);
+			vlan_newlink(vlan->ifname, hapd);
 #endif /* CONFIG_FULL_DYNAMIC_VLAN */
 		}
 
@@ -943,7 +995,7 @@ static void vlan_dynamic_remove(struct hostapd_data *hapd,
 		next = vlan->next;
 
 		if (vlan->vlan_id != VLAN_ID_WILDCARD &&
-		    hostapd_vlan_if_remove(hapd, vlan->ifname)) {
+		    vlan_if_remove(hapd, vlan)) {
 			wpa_printf(MSG_ERROR, "VLAN: Could not remove VLAN "
 				   "iface: %s: %s",
 				   vlan->ifname, strerror(errno));
@@ -1031,19 +1083,17 @@ struct hostapd_vlan * vlan_add_dynamic(struct hostapd_data *hapd,
 	os_snprintf(n->ifname, sizeof(n->ifname), "%s%d%s", ifname, vlan_id,
 		    pos);
 
-	if (hostapd_vlan_if_add(hapd, n->ifname)) {
+	n->next = hapd->conf->vlan;
+	hapd->conf->vlan = n;
+
+	/* hapd->conf->vlan needs this new VLAN here for WPA setup */
+	if (vlan_if_add(hapd, n, 0)) {
+		hapd->conf->vlan = n->next;
 		os_free(n);
 		n = NULL;
 		goto free_ifname;
 	}
 
-	n->next = hapd->conf->vlan;
-	hapd->conf->vlan = n;
-
-#ifdef CONFIG_FULL_DYNAMIC_VLAN
-	ifconfig_up(n->ifname);
-#endif /* CONFIG_FULL_DYNAMIC_VLAN */
-
 free_ifname:
 	os_free(ifname);
 	return n;
@@ -1073,7 +1123,7 @@ int vlan_remove_dynamic(struct hostapd_data *hapd, int vlan_id)
 		return 1;
 
 	if (vlan->dynamic_vlan == 0) {
-		hostapd_vlan_if_remove(hapd, vlan->ifname);
+		vlan_if_remove(hapd, vlan);
 #ifdef CONFIG_FULL_DYNAMIC_VLAN
 		vlan_dellink(vlan->ifname, hapd);
 #endif /* CONFIG_FULL_DYNAMIC_VLAN */

src/ap/wpa_auth.c

@@ -3388,6 +3388,98 @@ wpa_auth_add_group(struct wpa_authenticator *wpa_auth, int vlan_id)
 }
 
 
+/*
+ * Enforce that the group state machine for the VLAN is running, increase
+ * reference counter as interface is up. References might have been increased
+ * even if a negative value is returned.
+ * Returns: -1 on error (group missing, group already failed); otherwise, 0
+ */
+int wpa_auth_ensure_group(struct wpa_authenticator *wpa_auth, int vlan_id)
+{
+	struct wpa_group *group;
+
+	if (wpa_auth == NULL)
+		return 0;
+
+	group = wpa_auth->group;
+	while (group) {
+		if (group->vlan_id == vlan_id)
+			break;
+		group = group->next;
+	}
+
+	if (group == NULL) {
+		group = wpa_auth_add_group(wpa_auth, vlan_id);
+		if (group == NULL)
+			return -1;
+	}
+
+	wpa_printf(MSG_DEBUG,
+		   "WPA: Ensure group state machine running for VLAN ID %d",
+		   vlan_id);
+
+	wpa_group_get(wpa_auth, group);
+	group->num_setup_iface++;
+
+	if (group->wpa_group_state == WPA_GROUP_FATAL_FAILURE)
+		return -1;
+
+	return 0;
+}
+
+
+/*
+ * Decrease reference counter, expected to be zero afterwards.
+ * returns: -1 on error (group not found, group in fail state)
+ *          -2 if wpa_group is still referenced
+ *           0 else
+ */
+int wpa_auth_release_group(struct wpa_authenticator *wpa_auth, int vlan_id)
+{
+	struct wpa_group *group;
+	int ret = 0;
+
+	if (wpa_auth == NULL)
+		return 0;
+
+	group = wpa_auth->group;
+	while (group) {
+		if (group->vlan_id == vlan_id)
+			break;
+		group = group->next;
+	}
+
+	if (group == NULL)
+		return -1;
+
+	wpa_printf(MSG_DEBUG,
+		   "WPA: Try stopping group state machine for VLAN ID %d",
+		   vlan_id);
+
+	if (group->num_setup_iface <= 0) {
+		wpa_printf(MSG_ERROR,
+			   "WPA: wpa_auth_release_group called more often than wpa_auth_ensure_group for VLAN ID %d, skipping.",
+			   vlan_id);
+		return -1;
+	}
+	group->num_setup_iface--;
+
+	if (group->wpa_group_state == WPA_GROUP_FATAL_FAILURE)
+		ret = -1;
+
+	if (group->references > 1) {
+		wpa_printf(MSG_DEBUG,
+			   "WPA: Cannot stop group state machine for VLAN ID %d as references are still hold",
+			   vlan_id);
+		ret = -2;
+	}
+
+	wpa_group_put(wpa_auth, group);
+
+	return ret;
+}
+
+
 int wpa_auth_sta_set_vlan(struct wpa_state_machine *sm, int vlan_id)
 {
 	struct wpa_group *group;

src/ap/wpa_auth.h

@@ -325,4 +325,7 @@ int wpa_auth_radius_das_disconnect_pmksa(struct wpa_authenticator *wpa_auth,
 					 struct radius_das_attrs *attr);
 void wpa_auth_reconfig_group_keys(struct wpa_authenticator *wpa_auth);
 
+int wpa_auth_ensure_group(struct wpa_authenticator *wpa_auth, int vlan_id);
+int wpa_auth_release_group(struct wpa_authenticator *wpa_auth, int vlan_id);
+
 #endif /* WPA_AUTH_H */

src/ap/wpa_auth_i.h

@@ -171,6 +171,7 @@ struct wpa_group {
 #endif /* CONFIG_IEEE80211W */
 	/* Number of references except those in struct wpa_group->next */
 	unsigned int references;
+	unsigned int num_setup_iface;
 };