diff --git a/Cargo.lock b/Cargo.lock
index d460bb1a2de3..2801cc798902 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -3221,7 +3221,7 @@ dependencies = [
 
 [[package]]
 name = "shadowsocks"
-version = "1.21.0"
+version = "1.21.1"
 dependencies = [
  "aes",
  "arc-swap",
diff --git a/crates/shadowsocks/Cargo.toml b/crates/shadowsocks/Cargo.toml
index 7d0cedf4de0c..4406f81f2466 100644
--- a/crates/shadowsocks/Cargo.toml
+++ b/crates/shadowsocks/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "shadowsocks"
-version = "1.21.0"
+version = "1.21.1"
 authors = ["Shadowsocks Contributors"]
 description = "shadowsocks is a fast tunnel proxy that helps you bypass firewalls."
 repository = "https://github.com/shadowsocks/shadowsocks-rust"
diff --git a/crates/shadowsocks/src/config.rs b/crates/shadowsocks/src/config.rs
index 4195eab98ff6..f990e84c01ab 100644
--- a/crates/shadowsocks/src/config.rs
+++ b/crates/shadowsocks/src/config.rs
@@ -7,7 +7,7 @@ use std::{
     error,
     fmt::{self, Debug, Display},
     net::SocketAddr,
-    str::FromStr,
+    str::{self, FromStr},
     sync::Arc,
     time::Duration,
 };
@@ -100,15 +100,20 @@ impl Mode {
             _ => unreachable!(),
         }
     }
+
+    /// String representation of Mode
+    pub fn as_str(&self) -> &'static str {
+        match *self {
+            Mode::TcpOnly => "tcp_only",
+            Mode::TcpAndUdp => "tcp_and_udp",
+            Mode::UdpOnly => "udp_only",
+        }
+    }
 }
 
 impl fmt::Display for Mode {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        match *self {
-            Mode::TcpOnly => f.write_str("tcp_only"),
-            Mode::TcpAndUdp => f.write_str("tcp_and_udp"),
-            Mode::UdpOnly => f.write_str("udp_only"),
-        }
+        f.write_str(self.as_str())
     }
 }
 
@@ -125,6 +130,74 @@ impl FromStr for Mode {
     }
 }
 
+struct ModeVisitor;
+
+impl<'de> serde::de::Visitor<'de> for ModeVisitor {
+    type Value = Mode;
+
+    fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
+        formatter.write_str("Mode")
+    }
+
+    fn visit_str<E>(self, v: &str) -> Result<Self::Value, E>
+    where
+        E: serde::de::Error,
+    {
+        match v.parse::<Mode>() {
+            Ok(m) => Ok(m),
+            Err(_) => Err(serde::de::Error::invalid_value(serde::de::Unexpected::Str(v), &self)),
+        }
+    }
+
+    fn visit_string<E>(self, v: String) -> Result<Self::Value, E>
+    where
+        E: serde::de::Error,
+    {
+        self.visit_str::<E>(v.as_str())
+    }
+
+    fn visit_bytes<E>(self, v: &[u8]) -> Result<Self::Value, E>
+    where
+        E: serde::de::Error,
+    {
+        match str::from_utf8(v) {
+            Ok(v) => self.visit_str(v),
+            Err(_) => Err(serde::de::Error::invalid_value(serde::de::Unexpected::Bytes(v), &self)),
+        }
+    }
+
+    fn visit_byte_buf<E>(self, v: Vec<u8>) -> Result<Self::Value, E>
+    where
+        E: serde::de::Error,
+    {
+        match String::from_utf8(v) {
+            Ok(v) => self.visit_string(v),
+            Err(e) => Err(serde::de::Error::invalid_value(
+                serde::de::Unexpected::Bytes(&e.into_bytes()),
+                &self,
+            )),
+        }
+    }
+}
+
+impl<'de> serde::Deserialize<'de> for Mode {
+    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+    where
+        D: serde::Deserializer<'de>,
+    {
+        deserializer.deserialize_string(ModeVisitor)
+    }
+}
+
+impl serde::Serialize for Mode {
+    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+    where
+        S: serde::Serializer,
+    {
+        serializer.serialize_str(self.as_str())
+    }
+}
+
 /// Server's weight
 ///
 /// Commonly for using in balancer
@@ -986,6 +1059,74 @@ impl Display for ServerAddr {
     }
 }
 
+struct ServerAddrVisitor;
+
+impl<'de> serde::de::Visitor<'de> for ServerAddrVisitor {
+    type Value = ServerAddr;
+
+    fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
+        formatter.write_str("ServerAddr")
+    }
+
+    fn visit_str<E>(self, v: &str) -> Result<Self::Value, E>
+    where
+        E: serde::de::Error,
+    {
+        match v.parse::<ServerAddr>() {
+            Ok(m) => Ok(m),
+            Err(_) => Err(serde::de::Error::invalid_value(serde::de::Unexpected::Str(v), &self)),
+        }
+    }
+
+    fn visit_string<E>(self, v: String) -> Result<Self::Value, E>
+    where
+        E: serde::de::Error,
+    {
+        self.visit_str::<E>(v.as_str())
+    }
+
+    fn visit_bytes<E>(self, v: &[u8]) -> Result<Self::Value, E>
+    where
+        E: serde::de::Error,
+    {
+        match str::from_utf8(v) {
+            Ok(v) => self.visit_str(v),
+            Err(_) => Err(serde::de::Error::invalid_value(serde::de::Unexpected::Bytes(v), &self)),
+        }
+    }
+
+    fn visit_byte_buf<E>(self, v: Vec<u8>) -> Result<Self::Value, E>
+    where
+        E: serde::de::Error,
+    {
+        match String::from_utf8(v) {
+            Ok(v) => self.visit_string(v),
+            Err(e) => Err(serde::de::Error::invalid_value(
+                serde::de::Unexpected::Bytes(&e.into_bytes()),
+                &self,
+            )),
+        }
+    }
+}
+
+impl<'de> serde::Deserialize<'de> for ServerAddr {
+    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+    where
+        D: serde::Deserializer<'de>,
+    {
+        deserializer.deserialize_string(ServerAddrVisitor)
+    }
+}
+
+impl serde::Serialize for ServerAddr {
+    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+    where
+        S: serde::Serializer,
+    {
+        serializer.serialize_str(self.to_string().as_str())
+    }
+}
+
 impl From<SocketAddr> for ServerAddr {
     fn from(addr: SocketAddr) -> ServerAddr {
         ServerAddr::SocketAddr(addr)
@@ -1099,6 +1240,74 @@ impl Display for ManagerAddr {
     }
 }
 
+struct ManagerAddrVisitor;
+
+impl<'de> serde::de::Visitor<'de> for ManagerAddrVisitor {
+    type Value = ManagerAddr;
+
+    fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
+        formatter.write_str("ManagerAddr")
+    }
+
+    fn visit_str<E>(self, v: &str) -> Result<Self::Value, E>
+    where
+        E: serde::de::Error,
+    {
+        match v.parse::<ManagerAddr>() {
+            Ok(m) => Ok(m),
+            Err(_) => Err(serde::de::Error::invalid_value(serde::de::Unexpected::Str(v), &self)),
+        }
+    }
+
+    fn visit_string<E>(self, v: String) -> Result<Self::Value, E>
+    where
+        E: serde::de::Error,
+    {
+        self.visit_str::<E>(v.as_str())
+    }
+
+    fn visit_bytes<E>(self, v: &[u8]) -> Result<Self::Value, E>
+    where
+        E: serde::de::Error,
+    {
+        match str::from_utf8(v) {
+            Ok(v) => self.visit_str(v),
+            Err(_) => Err(serde::de::Error::invalid_value(serde::de::Unexpected::Bytes(v), &self)),
+        }
+    }
+
+    fn visit_byte_buf<E>(self, v: Vec<u8>) -> Result<Self::Value, E>
+    where
+        E: serde::de::Error,
+    {
+        match String::from_utf8(v) {
+            Ok(v) => self.visit_string(v),
+            Err(e) => Err(serde::de::Error::invalid_value(
+                serde::de::Unexpected::Bytes(&e.into_bytes()),
+                &self,
+            )),
+        }
+    }
+}
+
+impl<'de> serde::Deserialize<'de> for ManagerAddr {
+    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+    where
+        D: serde::Deserializer<'de>,
+    {
+        deserializer.deserialize_string(ManagerAddrVisitor)
+    }
+}
+
+impl serde::Serialize for ManagerAddr {
+    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+    where
+        S: serde::Serializer,
+    {
+        serializer.serialize_str(self.to_string().as_str())
+    }
+}
+
 impl From<SocketAddr> for ManagerAddr {
     fn from(addr: SocketAddr) -> ManagerAddr {
         ManagerAddr::SocketAddr(addr)