webui: Automatically check whether IPv6 is supported

plugin/smartdns-ui/src/http_server.rs

@@ -62,7 +62,8 @@ cfg_if::cfg_if! {
 const HTTP_SERVER_DEFAULT_PASSWORD: &str = "password";
 const HTTP_SERVER_DEFAULT_USERNAME: &str = "admin";
 const HTTP_SERVER_DEFAULT_WWW_ROOT: &str = "/usr/share/smartdns/wwwroot";
-const HTTP_SERVER_DEFAULT_IP: &str = "http://[::]:6080";
+const HTTP_SERVER_DEFAULT_IPV6: &str = "http://[::]:6080";
+const HTTP_SERVER_DEFAULT_IP: &str = "http://0.0.0.0:6080";
 
 #[derive(Clone)]
 pub struct HttpServerConfig {
@@ -77,8 +78,15 @@ pub struct HttpServerConfig {
 
 impl HttpServerConfig {
     pub fn new() -> Self {
+
+        let host_ip = if utils::is_ipv6_supported() {
+            HTTP_SERVER_DEFAULT_IPV6.to_string()
+        } else {
+            HTTP_SERVER_DEFAULT_IP.to_string()
+        };
+
         HttpServerConfig {
-            http_ip: HTTP_SERVER_DEFAULT_IP.to_string(),
+            http_ip: host_ip,
             http_root: HTTP_SERVER_DEFAULT_WWW_ROOT.to_string(),
             username: HTTP_SERVER_DEFAULT_USERNAME.to_string(),
             password: utils::hash_password(HTTP_SERVER_DEFAULT_PASSWORD, Some(1000)).unwrap(),

plugin/smartdns-ui/src/utils.rs

@@ -97,3 +97,12 @@ pub fn is_dir_writable(path: &str) -> bool {
     let path = std::ffi::CString::new(path).unwrap();
     unsafe { libc::access(path.as_ptr(), libc::W_OK) == 0 }
 }
+
+pub fn is_ipv6_supported() -> bool {
+    let sock = unsafe { libc::socket(libc::AF_INET6, libc::SOCK_STREAM, 0) };
+    if sock < 0 {
+        return false;
+    }
+    unsafe { libc::close(sock) };
+    true
+}