diff --git a/um_wasm/src/exports/kuwo.rs b/um_wasm/src/exports/kuwo.rs
index 49f129a..e037a61 100644
--- a/um_wasm/src/exports/kuwo.rs
+++ b/um_wasm/src/exports/kuwo.rs
@@ -23,13 +23,6 @@ impl JsKuwoHeader {
     pub fn quality_id(&self) -> u32 {
         self.0.get_quality_id()
     }
-
-    /// Create an instance of cipher (decipher) for decryption
-    #[wasm_bindgen(js_name=makeDecipher)]
-    pub fn make_decipher(&self, ekey: Option<String>) -> Result<JsCipher, JsError> {
-        let cipher = Decipher::new(&self.0, ekey).map_err(map_js_error)?;
-        Ok(JsCipher(cipher))
-    }
 }
 
 /// Create a decipher instance for "BoDian Music".
@@ -40,11 +33,11 @@ pub fn js_kuwo_bodian_cipher_factory(ekey: &str) -> Result<JsQMC2, JsError> {
 }
 
 /// Kuwo KWM v1
-#[wasm_bindgen(js_name=KWMCipherV1)]
-pub struct JsCipherV1(CipherV1);
+#[wasm_bindgen(js_name=KWMDecipherV1)]
+pub struct JsDecipherV1(CipherV1);
 
-#[wasm_bindgen(js_class=KWMCipherV1)]
-impl JsCipherV1 {
+#[wasm_bindgen(js_class=KWMDecipherV1)]
+impl JsDecipherV1 {
     /// Create a decipher instance for "Kuwo KWM v1".
     pub fn decrypt(&self, buffer: &mut [u8], offset: usize) {
         self.0.decrypt(buffer, offset)
@@ -58,11 +51,21 @@ pub fn js_kuwo_v2_cipher_factory(ekey: &str) -> Result<JsQMC2, JsError> {
 }
 
 /// Common V1/V2 wrapper interface, derived from `KuwoHeader.makeCipher`
-#[wasm_bindgen(js_name=KWMCipher)]
-pub struct JsCipher(Decipher);
+#[wasm_bindgen(js_name=KWMDecipher)]
+pub struct JsDecipher(Decipher);
+
+#[wasm_bindgen(js_class=KWMDecipher)]
+impl JsDecipher {
+    /// Create an instance of cipher (decipher) for decryption
+    #[wasm_bindgen(constructor)]
+    pub fn make_decipher(
+        header: &JsKuwoHeader,
+        ekey: Option<String>,
+    ) -> Result<JsDecipher, JsError> {
+        let cipher = Decipher::new(&header.0, ekey).map_err(map_js_error)?;
+        Ok(JsDecipher(cipher))
+    }
 
-#[wasm_bindgen(js_class=KWMCipher)]
-impl JsCipher {
     /// Decrypt buffer at given offset.
     pub fn decrypt(&self, buffer: &mut [u8], offset: usize) {
         self.0.decrypt(buffer, offset)