diff --git a/app/src/main/java/io/legado/app/help/crypto/AsymmetricCrypto.kt b/app/src/main/java/io/legado/app/help/crypto/AsymmetricCrypto.kt
index 1700479b7..2d9377d1e 100644
--- a/app/src/main/java/io/legado/app/help/crypto/AsymmetricCrypto.kt
+++ b/app/src/main/java/io/legado/app/help/crypto/AsymmetricCrypto.kt
@@ -39,7 +39,7 @@ class AsymmetricCrypto(algorithm: String) : HutoolAsymmetricCrypto(algorithm) {
             data is ByteArray -> func.invoke(data as ByteArray)
             data is String -> func.invoke(data as String)
             data is InputStream -> func.invoke(data as InputStream)
-            else -> null
+            else -> throw IllegalArgumentException("Unexpected data input")
         }
     }