AP: Add support for setting bridge network parameter

This allows setting a network parameter on the bridge that the BSS
belongs to.

This commit adds the needed functionality in driver_nl80211.c for the
Linux bridge implementation. In theory, this could be shared with
multiple Linux driver interfaces, but for now, only the main nl80211
interface is supported.

Signed-off-by: Kyeyoon Park <kyeyoonp@qca.qualcomm.com>

src/ap/ap_drv_ops.h

@@ -310,6 +310,16 @@ static inline int hostapd_drv_br_port_set_attr(struct hostapd_data *hapd,
 	return hapd->driver->br_port_set_attr(hapd->drv_priv, attr, val);
 }
 
+static inline int hostapd_drv_br_set_net_param(struct hostapd_data *hapd,
+					       enum drv_br_net_param param,
+					       unsigned int val)
+{
+	if (hapd->driver == NULL || hapd->drv_priv == NULL ||
+	    hapd->driver->br_set_net_param == NULL)
+		return -1;
+	return hapd->driver->br_set_net_param(hapd->drv_priv, param, val);
+}
+
 static inline int hostapd_drv_vendor_cmd(struct hostapd_data *hapd,
 					 int vendor_id, int subcmd,
 					 const u8 *data, size_t data_len,

src/drivers/driver.h

@@ -1378,6 +1378,10 @@ enum drv_br_port_attr {
 	DRV_BR_PORT_ATTR_HAIRPIN_MODE,
 };
 
+enum drv_br_net_param {
+	DRV_BR_NET_PARAM_GARP_ACCEPT,
+};
+
 
 /**
  * struct wpa_driver_ops - Driver interface API definition
@@ -2633,6 +2637,15 @@ struct wpa_driver_ops {
 	int (*br_port_set_attr)(void *priv, enum drv_br_port_attr attr,
 				unsigned int val);
 
+	/**
+	 * br_port_set_attr - Set a bridge network parameter
+	 * @param: Bridge parameter to set
+	 * @val: Value to be set
+	 * Returns: 0 on success, negative (<0) on failure
+	 */
+	int (*br_set_net_param)(void *priv, enum drv_br_net_param param,
+				unsigned int val);
+
 	/**
 	 * set_wowlan - Set wake-on-wireless triggers
 	 * @priv: Private driver interface data

src/drivers/driver_nl80211.c

@@ -9035,6 +9035,47 @@ static int wpa_driver_br_port_set_attr(void *priv, enum drv_br_port_attr attr,
 }
 
 
+static const char * drv_br_net_param_str(enum drv_br_net_param param)
+{
+	switch (param) {
+	case DRV_BR_NET_PARAM_GARP_ACCEPT:
+		return "arp_accept";
+	}
+
+	return NULL;
+}
+
+
+static int wpa_driver_br_set_net_param(void *priv, enum drv_br_net_param param,
+				       unsigned int val)
+{
+	struct i802_bss *bss = priv;
+	char path[128];
+	const char *param_txt;
+	int ip_version = 4;
+
+	param_txt = drv_br_net_param_str(param);
+	if (param_txt == NULL)
+		return -EINVAL;
+
+	switch (param) {
+		case DRV_BR_NET_PARAM_GARP_ACCEPT:
+			ip_version = 4;
+			break;
+		default:
+			return -EINVAL;
+	}
+
+	os_snprintf(path, sizeof(path), "/proc/sys/net/ipv%d/conf/%s/%s",
+		    ip_version, bss->brname, param_txt);
+
+	if (linux_write_system_file(path, val))
+		return -1;
+
+	return 0;
+}
+
+
 const struct wpa_driver_ops wpa_driver_nl80211_ops = {
 	.name = "nl80211",
 	.desc = "Linux nl80211/cfg80211",
@@ -9136,4 +9177,5 @@ const struct wpa_driver_ops wpa_driver_nl80211_ops = {
 	.br_add_ip_neigh = wpa_driver_br_add_ip_neigh,
 	.br_delete_ip_neigh = wpa_driver_br_delete_ip_neigh,
 	.br_port_set_attr = wpa_driver_br_port_set_attr,
+	.br_set_net_param = wpa_driver_br_set_net_param,
 };