diff --git a/app/src/main/java/io/legado/app/constant/AppPattern.kt b/app/src/main/java/io/legado/app/constant/AppPattern.kt
index 731a7296a..cfecd8bcc 100644
--- a/app/src/main/java/io/legado/app/constant/AppPattern.kt
+++ b/app/src/main/java/io/legado/app/constant/AppPattern.kt
@@ -13,6 +13,8 @@ object AppPattern {
 
     //dataURL图片类型
     val dataUriRegex = Regex("data:.*?;base64,(.*)")
+    //Base64字符串
+    val base64Regex = Regex("^[a-zA-Z0-9\\+\\/=]+$")
 
     val nameRegex = Regex("\\s+作\\s*者.*|\\s+\\S+\\s+著")
     val authorRegex = Regex("^\\s*作\\s*者[:：\\s]+|\\s+著")
diff --git a/app/src/main/java/io/legado/app/help/JsExtensions.kt b/app/src/main/java/io/legado/app/help/JsExtensions.kt
index d2ef307c4..97a00dd3a 100644
--- a/app/src/main/java/io/legado/app/help/JsExtensions.kt
+++ b/app/src/main/java/io/legado/app/help/JsExtensions.kt
@@ -6,6 +6,7 @@ import androidx.annotation.Keep
 import cn.hutool.crypto.digest.DigestUtil
 import cn.hutool.crypto.digest.HMac
 import cn.hutool.core.util.HexUtil
+import cn.hutool.crypto.symmetric.SymmetricCrypto
 import io.legado.app.constant.AppConst
 import io.legado.app.constant.AppConst.dateFormat
 import io.legado.app.constant.AppLog
@@ -648,6 +649,29 @@ interface JsExtensions {
 
 //******************对称加密解密************************//
 
+    /* 自动转换key iv 到ByteArray 支持base64 hex uft8*/
+    fun createSymmetricCrypto(
+        transformation: String,
+        key: String,
+        iv: String? = null
+    ): SymmetricCrypto {
+        return createSymmetricCrypto(
+            transformation,
+            StringUtils.encodeStringToByteArray(key),
+            StringUtils.encodeStringToByteArray(iv)
+        )
+    }
+
+    /* 调用SymmetricCrypto key为null时使用随机密钥*/
+    fun createSymmetricCrypto(
+        transformation: String,
+        key: ByteArray? = null,
+        iv: ByteArray? = null
+    ): SymmetricCrypto {
+        val symmetricCrypto = SymmetricCrypto(transformation, key)
+        return if (iv != null && !iv.isEmpty()) symmetricCrypto.setIv(iv) else symmetricCrypto
+    }
+
 //******************消息摘要/散列消息鉴别码************************//
 
     /**
diff --git a/app/src/main/java/io/legado/app/utils/StringExtensions.kt b/app/src/main/java/io/legado/app/utils/StringExtensions.kt
index 1228907b5..9d62eec3e 100644
--- a/app/src/main/java/io/legado/app/utils/StringExtensions.kt
+++ b/app/src/main/java/io/legado/app/utils/StringExtensions.kt
@@ -6,7 +6,9 @@ import android.icu.text.Collator
 import android.icu.util.ULocale
 import android.net.Uri
 import android.text.Editable
+import cn.hutool.core.lang.Validator
 import io.legado.app.constant.AppPattern.dataUriRegex
+import io.legado.app.constant.AppPattern.base64Regex
 import java.io.File
 import java.util.*
 
@@ -39,6 +41,11 @@ fun String?.isDataUrl() =
         dataUriRegex.matches(it)
     } ?: false
 
+fun String?.isBase64() =
+    this?.let {
+        base64Regex.matches(it)
+    } ?: false
+
 fun String?.isJson(): Boolean =
     this?.run {
         val str = this.trim()
diff --git a/app/src/main/java/io/legado/app/utils/StringUtils.kt b/app/src/main/java/io/legado/app/utils/StringUtils.kt
index 770c48dc0..4c5dda84c 100644
--- a/app/src/main/java/io/legado/app/utils/StringUtils.kt
+++ b/app/src/main/java/io/legado/app/utils/StringUtils.kt
@@ -1,8 +1,12 @@
 package io.legado.app.utils
 
+import android.util.Base64
 import android.annotation.SuppressLint
 import android.text.TextUtils.isEmpty
 
+import cn.hutool.core.util.HexUtil
+import cn.hutool.core.lang.Validator
+
 import java.text.DecimalFormat
 import java.text.SimpleDateFormat
 import java.util.*
@@ -287,4 +291,16 @@ object StringUtils {
         return buf.toString()
     }
 
+    /**
+     * 自动识别Base64 Hex Utf8字符串 并转成ByteArray
+     */
+    fun encodeStringToByteArray(str: String?): ByteArray? {
+        return when {
+            str.isNullOrBlank() -> null
+            Validator.isHex(str) -> HexUtil.decodeHex(str)
+            str.isBase64() -> Base64.decode(str, Base64.DEFAULT)
+            else -> str.encodeToByteArray()
+        }
+    }
+
 }