Simplify driver_ops for virtual interface add/remove

There is no absolute requirement for separating address allocation
into separate functions, so simplify the driver wrapper interface
to use just if_add and if_remove instead of adding the new
alloc_interface_addr() and release_interface_addr() functions.

if_add() can now indicate if the driver forced a different interface
name or address on the virtual interface.

src/ap/ap_drv_ops.c

@@ -242,7 +242,10 @@ static int hostapd_set_beacon(struct hostapd_data *hapd,
 
 static int hostapd_vlan_if_add(struct hostapd_data *hapd, const char *ifname)
 {
-	return hostapd_if_add(hapd, WPA_IF_AP_VLAN, ifname, NULL, NULL, NULL);
+	char force_ifname[IFNAMSIZ];
+	u8 if_addr[ETH_ALEN];
+	return hostapd_if_add(hapd, WPA_IF_AP_VLAN, ifname, NULL, NULL, NULL,
+			      force_ifname, if_addr);
 }
 
 static int hostapd_vlan_if_remove(struct hostapd_data *hapd,
@@ -404,12 +407,12 @@ int hostapd_set_ssid(struct hostapd_data *hapd, const u8 *buf, size_t len)
 
 int hostapd_if_add(struct hostapd_data *hapd, enum wpa_driver_if_type type,
 		   const char *ifname, const u8 *addr, void *bss_ctx,
-		   void **drv_priv)
+		   void **drv_priv, char *force_ifname, u8 *if_addr)
 {
 	if (hapd->driver == NULL || hapd->driver->if_add == NULL)
 		return -1;
 	return hapd->driver->if_add(hapd->drv_priv, type, ifname, addr,
-				    bss_ctx, drv_priv);
+				    bss_ctx, drv_priv, force_ifname, if_addr);
 }
 
 

src/ap/ap_drv_ops.h

@@ -27,7 +27,7 @@ int hostapd_get_ssid(struct hostapd_data *hapd, u8 *buf, size_t len);
 int hostapd_set_ssid(struct hostapd_data *hapd, const u8 *buf, size_t len);
 int hostapd_if_add(struct hostapd_data *hapd, enum wpa_driver_if_type type,
 		   const char *ifname, const u8 *addr, void *bss_ctx,
-		   void **drv_priv);
+		   void **drv_priv, char *force_ifname, u8 *if_addr);
 int hostapd_if_remove(struct hostapd_data *hapd, enum wpa_driver_if_type type,
 		      const char *ifname);
 int hostapd_set_ieee8021x(struct hostapd_data *hapd,

src/ap/hostapd.c

@@ -468,6 +468,8 @@ static int hostapd_setup_bss(struct hostapd_data *hapd, int first)
 	struct hostapd_bss_config *conf = hapd->conf;
 	u8 ssid[HOSTAPD_MAX_SSID_LEN + 1];
 	int ssid_len, set_ssid;
+	char force_ifname[IFNAMSIZ];
+	u8 if_addr[ETH_ALEN];
 
 	if (!first) {
 		if (hostapd_mac_comp_empty(hapd->conf->bssid) == 0) {
@@ -492,7 +494,7 @@ static int hostapd_setup_bss(struct hostapd_data *hapd, int first)
 		hapd->interface_added = 1;
 		if (hostapd_if_add(hapd->iface->bss[0], WPA_IF_AP_BSS,
 				   hapd->conf->iface, hapd->own_addr, hapd,
-				   &hapd->drv_priv)) {
+				   &hapd->drv_priv, force_ifname, if_addr)) {
 			wpa_printf(MSG_ERROR, "Failed to add BSS (BSSID="
 				   MACSTR ")", MAC2STR(hapd->own_addr));
 			return -1;

src/drivers/driver.h

@@ -1490,11 +1490,16 @@ struct wpa_driver_ops {
 	 * @bss_ctx: BSS context for %WPA_IF_AP_BSS interfaces
 	 * @drv_priv: Pointer for overwriting the driver context or %NULL if
 	 *	not allowed (applies only to %WPA_IF_AP_BSS type)
+	 * @force_ifname: Buffer for returning an interface name that the
+	 *	driver ended up using if it differs from the requested ifname
+	 * @if_addr: Buffer for returning the allocated interface address
+	 *	(this may differ from the requested addr if the driver cannot
+	 *	change interface address)
 	 * Returns: 0 on success, -1 on failure
 	 */
 	int (*if_add)(void *priv, enum wpa_driver_if_type type,
 		      const char *ifname, const u8 *addr, void *bss_ctx,
-		      void **drv_priv);
+		      void **drv_priv, char *force_ifname, u8 *if_addr);
 
 	/**
 	 * if_remove - Remove a virtual interface
@@ -1635,40 +1640,6 @@ struct wpa_driver_ops {
 			   const u8 *dst, const u8 *src, const u8 *bssid,
 			   const u8 *data, size_t data_len);
 
-	/**
-	 * alloc_interface_addr - Allocate a virtual interface address
-	 * @priv: Private driver interface data
-	 * @addr: Buffer for returning the address
-	 * @ifname: Buffer for returning interface name (if needed)
-	 * Returns: 0 on success, -1 on failure
-	 *
-	 * This command pre-allocates an interface address for a new virtual
-	 * interface. This can be used before creating a virtual interface if
-	 * the interface mode (e.g., AP vs. station) is not yet known, but the
-	 * address of the virtual interface is already needed. This helps with
-	 * drivers that cannot change interface mode without destroying and
-	 * re-creating the interface. If the driver requires a specific
-	 * interface name to be used, the ifname buffer (up to IFNAMSIZ
-	 * characters) will be used to indicate which name must be used for
-	 * this virtual interface.
-	 *
-	 * The allocated address can be used in a if_add() call to request a
-	 * specific bssid.
-	 */
-	int (*alloc_interface_addr)(void *priv, u8 *addr, char *ifname);
-
-	/**
-	 * release_interface_addr - Release a virtual interface address
-	 * @priv: Private driver interface data
-	 * @addr: Address to be freed from alloc_interface_addr()
-	 *
-	 * This command is used to release a virtual interface address that was
-	 * allocated with alloc_interface_addr(), but has not yet been used
-	 * with if_add() to actually create the interface. This allows the
-	 * driver to release the pending allocation for a new interface.
-	 */
-	void (*release_interface_addr)(void *priv, const u8 *addr);
-
 	/**
 	 * remain_on_channel - Remain awake on a channel
 	 * @priv: Private driver interface data

src/drivers/driver_ndis.c

@@ -3266,8 +3266,6 @@ const struct wpa_driver_ops wpa_driver_ndis_ops = {
 	NULL /* set_supp_port */,
 	NULL /* set_wds_sta */,
 	NULL /* send_action */,
-	NULL /* alloc_interface_addr */,
-	NULL /* release_interface_addr */,
 	NULL /* remain_on_channel */,
 	NULL /* cancel_remain_on_channel */,
 	NULL /* probe_req_report */,

src/drivers/driver_nl80211.c

@@ -4760,7 +4760,8 @@ static enum nl80211_iftype wpa_driver_nl80211_if_type(
 
 static int wpa_driver_nl80211_if_add(void *priv, enum wpa_driver_if_type type,
 				     const char *ifname, const u8 *addr,
-				     void *bss_ctx, void **drv_priv)
+				     void *bss_ctx, void **drv_priv,
+				     char *force_ifname, u8 *if_addr)
 {
 	struct i802_bss *bss = priv;
 	struct wpa_driver_nl80211_data *drv = bss->drv;
@@ -4775,6 +4776,8 @@ static int wpa_driver_nl80211_if_add(void *priv, enum wpa_driver_if_type type,
 	}
 #endif /* HOSTAPD */
 
+	if (addr)
+		os_memcpy(if_addr, addr, ETH_ALEN);
 	ifidx = nl80211_create_iface(drv, ifname,
 				     wpa_driver_nl80211_if_type(type), addr,
 				     0);
@@ -4785,6 +4788,10 @@ static int wpa_driver_nl80211_if_add(void *priv, enum wpa_driver_if_type type,
 		return -1;
 	}
 
+	if (!addr &&
+	    linux_get_ifhwaddr(drv->ioctl_sock, bss->ifname, if_addr) < 0)
+		return -1;
+
 #ifdef HOSTAPD
 	if (type == WPA_IF_AP_BSS) {
 		if (linux_set_iface_flags(drv->ioctl_sock, ifname, 1)) {
@@ -5054,35 +5061,6 @@ static int wpa_driver_nl80211_probe_req_report(void *priv, int report)
 }
 
 
-static int wpa_driver_nl80211_alloc_interface_addr(void *priv, u8 *addr,
-						   char *ifname)
-{
-	struct i802_bss *bss = priv;
-	struct wpa_driver_nl80211_data *drv = bss->drv;
-
-	if (ifname)
-		ifname[0] = '\0';
-
-	if (linux_get_ifhwaddr(drv->ioctl_sock, bss->ifname, addr) < 0)
-		return -1;
-
-	if (addr[0] & 0x02) {
-		/* TODO: add support for generating multiple addresses */
-		addr[0] ^= 0x80;
-	} else
-		addr[0] = 0x02; /* locally administered */
-
-	return 0;
-}
-
-
-static void wpa_driver_nl80211_release_interface_addr(void *priv,
-						      const u8 *addr)
-{
-	/* TODO: keep list of allocated address and release them here */
-}
-
-
 static int nl80211_disable_11b_rates(struct wpa_driver_nl80211_data *drv,
 				     int ifindex, int disabled)
 {
@@ -5312,8 +5290,6 @@ const struct wpa_driver_ops wpa_driver_nl80211_ops = {
 	.cancel_remain_on_channel =
 	wpa_driver_nl80211_cancel_remain_on_channel,
 	.probe_req_report = wpa_driver_nl80211_probe_req_report,
-	.alloc_interface_addr = wpa_driver_nl80211_alloc_interface_addr,
-	.release_interface_addr = wpa_driver_nl80211_release_interface_addr,
 	.disable_11b_rates = wpa_driver_nl80211_disable_11b_rates,
 	.deinit_ap = wpa_driver_nl80211_deinit_ap,
 	.resume = wpa_driver_nl80211_resume,

src/drivers/driver_test.c

@@ -1014,12 +1014,27 @@ static int test_driver_bss_remove(void *priv, const char *ifname)
 
 static int test_driver_if_add(void *priv, enum wpa_driver_if_type type,
 			      const char *ifname, const u8 *addr,
-			      void *bss_ctx, void **drv_priv)
+			      void *bss_ctx, void **drv_priv,
+			      char *force_ifname, u8 *if_addr)
 {
+	struct test_driver_bss *dbss = priv;
+	struct wpa_driver_test_data *drv = dbss->drv;
+
 	wpa_printf(MSG_DEBUG, "%s(type=%d ifname=%s bss_ctx=%p)",
 		   __func__, type, ifname, bss_ctx);
+	if (addr)
+		os_memcpy(if_addr, addr, ETH_ALEN);
+	else {
+		drv->alloc_iface_idx++;
+		if_addr[0] = 0x02; /* locally administered */
+		sha1_prf(drv->own_addr, ETH_ALEN,
+			 "hostapd test addr generation",
+			 (const u8 *) &drv->alloc_iface_idx,
+			 sizeof(drv->alloc_iface_idx),
+			 if_addr + 1, ETH_ALEN - 1);
+	}
 	if (type == WPA_IF_AP_BSS)
-		return test_driver_bss_add(priv, ifname, addr, bss_ctx,
+		return test_driver_bss_add(priv, ifname, if_addr, bss_ctx,
 					   drv_priv);
 	return 0;
 }
@@ -2616,30 +2631,6 @@ static int wpa_driver_test_send_action(void *priv, unsigned int freq,
 }
 
 
-static int wpa_driver_test_alloc_interface_addr(void *priv, u8 *addr,
-						char *ifname)
-{
-	struct test_driver_bss *dbss = priv;
-	struct wpa_driver_test_data *drv = dbss->drv;
-
-	if (ifname)
-		ifname[0] = '\0';
-
-	drv->alloc_iface_idx++;
-	addr[0] = 0x02; /* locally administered */
-	sha1_prf(drv->own_addr, ETH_ALEN, "hostapd test addr generation",
-		 (const u8 *) &drv->alloc_iface_idx,
-		 sizeof(drv->alloc_iface_idx),
-		 addr + 1, ETH_ALEN - 1);
-	return 0;
-}
-
-
-static void wpa_driver_test_release_interface_addr(void *priv, const u8 *addr)
-{
-}
-
-
 static void test_remain_on_channel_timeout(void *eloop_ctx, void *timeout_ctx)
 {
 	struct wpa_driver_test_data *drv = eloop_ctx;
@@ -2755,8 +2746,6 @@ const struct wpa_driver_ops wpa_driver_test_ops = {
 	.scan2 = wpa_driver_test_scan,
 	.set_freq = wpa_driver_test_set_freq,
 	.send_action = wpa_driver_test_send_action,
-	.alloc_interface_addr = wpa_driver_test_alloc_interface_addr,
-	.release_interface_addr = wpa_driver_test_release_interface_addr,
 	.remain_on_channel = wpa_driver_test_remain_on_channel,
 	.cancel_remain_on_channel = wpa_driver_test_cancel_remain_on_channel,
 	.probe_req_report = wpa_driver_test_probe_req_report,

wpa_supplicant/driver_i.h

@@ -394,20 +394,26 @@ static inline int wpa_drv_send_action(struct wpa_supplicant *wpa_s,
 	return -1;
 }
 
-static inline int wpa_drv_alloc_interface_addr(struct wpa_supplicant *wpa_s,
-					       u8 *addr, char *ifname)
+static inline int wpa_drv_if_add(struct wpa_supplicant *wpa_s,
+				 enum wpa_driver_if_type type,
+				 const char *ifname, const u8 *addr,
+				 void *bss_ctx, char *force_ifname,
+				 u8 *if_addr)
 {
-	if (wpa_s->driver->alloc_interface_addr)
-		return wpa_s->driver->alloc_interface_addr(wpa_s->drv_priv,
-							   addr, ifname);
+	if (wpa_s->driver->if_add)
+		return wpa_s->driver->if_add(wpa_s->drv_priv, type, ifname,
+					     addr, bss_ctx, NULL, force_ifname,
+					     if_addr);
 	return -1;
 }
 
-static inline void wpa_drv_release_interface_addr(struct wpa_supplicant *wpa_s,
-						  const u8 *addr)
+static inline int wpa_drv_if_remove(struct wpa_supplicant *wpa_s,
+				    enum wpa_driver_if_type type,
+				    const char *ifname)
 {
-	if (wpa_s->driver->release_interface_addr)
-		wpa_s->driver->release_interface_addr(wpa_s->drv_priv, addr);
+	if (wpa_s->driver->if_remove)
+		return wpa_s->driver->if_remove(wpa_s->drv_priv, type, ifname);
+	return -1;
 }
 
 static inline int wpa_drv_remain_on_channel(struct wpa_supplicant *wpa_s,