diff --git a/vnt-cli/src/config/mod.rs b/vnt-cli/src/config/mod.rs
index 97415f2..62b1318 100644
--- a/vnt-cli/src/config/mod.rs
+++ b/vnt-cli/src/config/mod.rs
@@ -158,7 +158,8 @@ pub fn read_config(file_path: &str) -> io::Result<(Config, bool)> {
         punch_model,
         file_conf.port,
         file_conf.first_latency,
-    );
+    )
+    .unwrap();
     Ok((config, file_conf.cmd))
 }
 
diff --git a/vnt-cli/src/main.rs b/vnt-cli/src/main.rs
index 1f823c9..f460bce 100644
--- a/vnt-cli/src/main.rs
+++ b/vnt-cli/src/main.rs
@@ -288,7 +288,8 @@ fn main() {
             punch_model,
             port,
             first_latency,
-        );
+        )
+        .unwrap();
         (config, cmd)
     };
     println!("version {}", vnt::VNT_VERSION);
diff --git a/vnt-jni/src/vnt_util.rs b/vnt-jni/src/vnt_util.rs
index 9e6b478..7e69881 100644
--- a/vnt-jni/src/vnt_util.rs
+++ b/vnt-jni/src/vnt_util.rs
@@ -130,7 +130,7 @@ fn new_sync(env: &mut JNIEnv, config: JObject) -> Result<VntUtilSync, Error> {
     for addr in stun_server_str.split(",") {
         stun_server.push(addr.trim().to_string());
     }
-    let config = Config::new(
+    let config = match Config::new(
         false,
         token,
         device_id,
@@ -154,7 +154,17 @@ fn new_sync(env: &mut JNIEnv, config: JObject) -> Result<VntUtilSync, Error> {
         PunchModel::All,
         port,
         first_latency,
-    );
+    ) {
+        Ok(config) => config,
+        Err(e) => {
+            env.throw_new(
+                "java/lang/RuntimeException",
+                format!("vnt start error {}", e),
+            )
+            .expect("throw");
+            return Err(Error::JavaException);
+        }
+    };
     match VntUtilSync::new(config) {
         Ok(vnt_util) => Ok(vnt_util),
         Err(e) => {
diff --git a/vnt/src/core/mod.rs b/vnt/src/core/mod.rs
index 78abfe5..0997f35 100644
--- a/vnt/src/core/mod.rs
+++ b/vnt/src/core/mod.rs
@@ -600,13 +600,22 @@ impl Config {
         punch_model: PunchModel,
         port: u16,
         first_latency: bool,
-    ) -> Self {
+    ) -> Result<Self, Error> {
         for x in stun_server.iter_mut() {
             if !x.contains(":") {
                 x.push_str(":3478");
             }
         }
-        Self {
+        if token.is_empty() || token.len() > 128 {
+            return Err(Error::Stop(String::from("token too long")));
+        }
+        if device_id.is_empty() || device_id.len() > 128 {
+            return Err(Error::Stop(String::from("device_id too long")));
+        }
+        if name.is_empty() || name.len() > 128 {
+            return Err(Error::Stop(String::from("name too long")));
+        }
+        Ok(Self {
             tap,
             token,
             device_id,
@@ -631,6 +640,6 @@ impl Config {
             punch_model,
             port,
             first_latency,
-        }
+        })
     }
 }