Added a mechanism for quering driver wrappers for available interfaces

The new INTERFACE_LIST global control interface command can be used to
request a list of all available network interfaces that could be used
with the enabled driver wrappers. This could be used to enable
interfaces automatically by external programs (e.g., wpa_gui).

src/drivers/driver.h

@@ -125,6 +125,23 @@ struct wpa_scan_results {
 	size_t num;
 };
 
+/**
+ * struct wpa_interface_info - Network interface information
+ * @next: Pointer to the next interface or NULL if this is the last one
+ * @ifname: Interface name that can be used with init() or init2()
+ * @desc: Human readable adapter description (e.g., vendor/model) or NULL if
+ *	not available
+ * @drv_bame: struct wpa_driver_ops::name (note: unlike other strings, this one
+ *	is not an allocated copy, i.e., get_interfaces() caller will not free
+ *	this)
+ */
+struct wpa_interface_info {
+	struct wpa_interface_info *next;
+	char *ifname;
+	char *desc;
+	const char *drv_name;
+};
+
 /**
  * struct wpa_driver_associate_params - Association parameters
  * Data for struct wpa_driver_ops::associate().
@@ -991,6 +1008,15 @@ struct wpa_driver_ops {
 	 * uses global data.
 	 */
 	void * (*init2)(void *ctx, const char *ifname, void *global_priv);
+
+	/**
+	 * get_interfaces - Get information about available interfaces
+	 * @global_priv: private driver global data from global_init()
+	 * Returns: Allocated buffer of interface information (caller is
+	 * responsible for freeing the data structure) on success, NULL on
+	 * failure
+	 */
+	struct wpa_interface_info * (*get_interfaces)(void *global_priv);
 };
 
 /* Function to check whether a driver is for wired connections */

src/drivers/driver_ndis.c

@@ -2887,5 +2887,6 @@ const struct wpa_driver_ops wpa_driver_ndis_ops = {
 	NULL /* set_country */,
 	NULL /* global_init */,
 	NULL /* global_deinit */,
-	NULL /* init2 */
+	NULL /* init2 */,
+	NULL /* get_interfaces */
 };

src/drivers/driver_privsep.c

@@ -778,7 +778,8 @@ struct wpa_driver_ops wpa_driver_privsep_ops = {
 	NULL /* set_country */,
 	NULL /* global_init */,
 	NULL /* global_deinit */,
-	NULL /* init2 */
+	NULL /* init2 */,
+	NULL /* get_interfaces */
 };
 
 

src/drivers/driver_test.c

@@ -1147,6 +1147,29 @@ static void wpa_driver_test_global_deinit(void *priv)
 }
 
 
+static struct wpa_interface_info *
+wpa_driver_test_get_interfaces(void *global_priv)
+{
+	/* struct wpa_driver_test_global *global = priv; */
+	struct wpa_interface_info *iface;
+
+	iface = os_zalloc(sizeof(*iface));
+	if (iface == NULL)
+		return iface;
+	iface->ifname = os_strdup("sta0");
+	iface->desc = os_strdup("test interface 0");
+	iface->drv_name = "test";
+	iface->next = os_zalloc(sizeof(*iface));
+	if (iface->next) {
+		iface->next->ifname = os_strdup("sta1");
+		iface->next->desc = os_strdup("test interface 1");
+		iface->next->drv_name = "test";
+	}
+
+	return iface;
+}
+
+
 const struct wpa_driver_ops wpa_driver_test_ops = {
 	"test",
 	"wpa_supplicant test driver",
@@ -1200,5 +1223,6 @@ const struct wpa_driver_ops wpa_driver_test_ops = {
 	NULL /* set_country */,
 	wpa_driver_test_global_init,
 	wpa_driver_test_global_deinit,
-	wpa_driver_test_init2
+	wpa_driver_test_init2,
+	wpa_driver_test_get_interfaces
 };

wpa_supplicant/ctrl_iface.c

@@ -30,7 +30,10 @@
 #include "wps_supplicant.h"
 #include "wps/wps.h"
 
+extern struct wpa_driver_ops *wpa_supplicant_drivers[];
 
+static int wpa_supplicant_global_iface_list(struct wpa_global *global,
+					    char *buf, int len);
 static int wpa_supplicant_global_iface_interfaces(struct wpa_global *global,
 						  char *buf, int len);
 
@@ -1624,6 +1627,9 @@ char * wpa_supplicant_ctrl_iface_process(struct wpa_supplicant *wpa_s,
 	} else if (os_strncmp(buf, "AP_SCAN ", 8) == 0) {
 		if (wpa_supplicant_ctrl_iface_ap_scan(wpa_s, buf + 8))
 			reply_len = -1;
+	} else if (os_strcmp(buf, "INTERFACE_LIST") == 0) {
+		reply_len = wpa_supplicant_global_iface_list(
+			wpa_s->global, reply, reply_size);
 	} else if (os_strcmp(buf, "INTERFACES") == 0) {
 		reply_len = wpa_supplicant_global_iface_interfaces(
 			wpa_s->global, reply, reply_size);
@@ -1739,6 +1745,63 @@ static int wpa_supplicant_global_iface_remove(struct wpa_global *global,
 }
 
 
+static void wpa_free_iface_info(struct wpa_interface_info *iface)
+{
+	struct wpa_interface_info *prev;
+
+	while (iface) {
+		prev = iface;
+		iface = iface->next;
+
+		os_free(prev->ifname);
+		os_free(prev->desc);
+		os_free(prev);
+	}
+}
+
+
+static int wpa_supplicant_global_iface_list(struct wpa_global *global,
+					    char *buf, int len)
+{
+	int i, res;
+	struct wpa_interface_info *iface = NULL, *last = NULL, *tmp;
+	char *pos, *end;
+
+	for (i = 0; wpa_supplicant_drivers[i]; i++) {
+		struct wpa_driver_ops *drv = wpa_supplicant_drivers[i];
+		if (drv->get_interfaces == NULL)
+			continue;
+		tmp = drv->get_interfaces(global->drv_priv);
+		if (tmp == NULL)
+			continue;
+
+		if (last == NULL)
+			iface = last = tmp;
+		else
+			last->next = tmp;
+		while (last->next)
+			last = last->next;
+	}
+
+	pos = buf;
+	end = buf + len;
+	for (tmp = iface; tmp; tmp = tmp->next) {
+		res = os_snprintf(pos, end - pos, "%s\t%s\t%s\n",
+				  tmp->drv_name, tmp->ifname,
+				  tmp->desc ? tmp->desc : "");
+		if (res < 0 || res >= end - pos) {
+			*pos = '\0';
+			break;
+		}
+		pos += res;
+	}
+
+	wpa_free_iface_info(iface);
+
+	return pos - buf;
+}
+
+
 static int wpa_supplicant_global_iface_interfaces(struct wpa_global *global,
 						  char *buf, int len)
 {
@@ -1791,6 +1854,9 @@ char * wpa_supplicant_global_ctrl_iface_process(struct wpa_global *global,
 	} else if (os_strncmp(buf, "INTERFACE_REMOVE ", 17) == 0) {
 		if (wpa_supplicant_global_iface_remove(global, buf + 17))
 			reply_len = -1;
+	} else if (os_strcmp(buf, "INTERFACE_LIST") == 0) {
+		reply_len = wpa_supplicant_global_iface_list(
+			global, reply, reply_size);
 	} else if (os_strcmp(buf, "INTERFACES") == 0) {
 		reply_len = wpa_supplicant_global_iface_interfaces(
 			global, reply, reply_size);

wpa_supplicant/wpa_cli.c

@@ -1120,6 +1120,13 @@ static int wpa_cli_cmd_interface_remove(struct wpa_ctrl *ctrl, int argc,
 }
 
 
+static int wpa_cli_cmd_interface_list(struct wpa_ctrl *ctrl, int argc,
+				      char *argv[])
+{
+	return wpa_ctrl_command(ctrl, "INTERFACE_LIST");
+}
+
+
 struct wpa_cli_cmd {
 	const char *cmd;
 	int (*handler)(struct wpa_ctrl *ctrl, int argc, char *argv[]);
@@ -1166,6 +1173,7 @@ static struct wpa_cli_cmd wpa_cli_commands[] = {
 	{ "terminate", wpa_cli_cmd_terminate },
 	{ "interface_add", wpa_cli_cmd_interface_add },
 	{ "interface_remove", wpa_cli_cmd_interface_remove },
+	{ "interface_list", wpa_cli_cmd_interface_list },
 	{ "ap_scan", wpa_cli_cmd_ap_scan },
 	{ "stkstart", wpa_cli_cmd_stkstart },
 	{ "ft_ds", wpa_cli_cmd_ft_ds },