int (*notify) (DBusMessage *msg, struct vpn_provider *provider);
int (*connect) (struct vpn_provider *provider,
struct connman_task *task, const char *if_name,
int (*notify) (DBusMessage *msg, struct vpn_provider *provider);
int (*connect) (struct vpn_provider *provider,
struct connman_task *task, const char *if_name,