問題描述

我們很難在 ColdFusion 中解密之前使用 3DES 和 C# 加密的字符串.這是我們最初用來加密字符串的代碼:

We are having difficulty decrypting a string in ColdFusion that was previously encrypted with 3DES and C#. Here is the code we used to encrypt the string initially:

    public static string EncryptTripleDES(string plaintext, string key)
    {
    TripleDESCryptoServiceProvider DES = new TripleDESCryptoServiceProvider();
    MD5CryptoServiceProvider hashMD5 = new MD5CryptoServiceProvider();
    DES.Key = hashMD5.ComputeHash(ASCIIEncoding.ASCII.GetBytes(key));
    DES.Mode = CipherMode.ECB;
    ICryptoTransform DESEncrypt = DES.CreateEncryptor();
    byte[] Buffer = ASCIIEncoding.ASCII.GetBytes(plaintext);

    string EncString = Convert.ToBase64String(DESEncrypt.TransformFinalBlock(Buffer, 0, Buffer.Length));
    EncString = EncString.Replace("+", "@@12");

    return EncString;
    }

我們已嘗試使用此處的建議:

We have tried using the suggestions here:

TripleDES 加密 - .NET 和 ColdFusion 效果不佳

..沒有運氣.這是我們的 CF 代碼和錯誤:

..with no luck. Here is our CF code and the error:

  <cfset variables.theKey = "blahblah" />
  <cfset variables.theAlgorithm = "DESede/CBC/PKCS5Padding">
  <cfset variables.theEncoding = "Base64">
  <cfset strTest = decrypt(#DB.PASSWORD#, variables.theKey, variables.theAlgorithm, variables.theEncoding)>

錯誤返回:嘗試加密或解密輸入字符串時出錯:''無法解碼字符串blahblah"

Error returned: An error occurred while trying to encrypt or decrypt your input string: '' Can not decode string "blahblah"

所以，看起來它是在嘗試解密密鑰而不是字符串，但這不是 ColdFusion 中解密函數的概述方式.有什么想法嗎?

So, it looks like it's trying to decrypt the key and not the string, but that's not how the decrypt function is outlined in ColdFusion. Any ideas?

更新:嘗試使用以下 CF 代碼，但返回的錯誤仍然是嘗試加密或解密您的輸入字符串時發生錯誤:未正確填充最終塊."

UPDATE: Attempted to use the following CF code, but the error returned is still "An error occurred while trying to encrypt or decrypt your input string: Given final block not properly padded."

<cfset dbPassword  = "Hx41SYUrmnFPa31QCH1ArCHN1YOF8IAL">
<cfset finalText   = replace(dbPassword, "@@12", "+", "all")>
<cfset theKey      = "abcdefgh">
<cfset theKeyInBase64 = toBase64(theKey)>
<cfset hashedKey   = hash( theKeyInBase64, "md5" )>
<cfset padBytes    = left( hashedKey, 16 )>
<cfset keyBytes    = binaryDecode( hashedKey & padBytes , "hex" )>
<cfset finalKey    = binaryEncode( keyBytes, "base64" )>
<cfset decrypted = decrypt( finalText, finalKey, "DESede/ECB/PKCS5Padding", "base64" )>
Decrypted String: <cfdump var="#decrypted#">

更新:

如果您關注評論，解決方案是更改:

The solution if you follow the comments was to change:

<cfset hashedKey   = hash( theKeyInBase64, "md5" )>

收件人:

<cfset hashedKey   = hash( theKey, "md5" )>

最后的代碼是這樣的:

<cfset dbPassword  = "Hx41SYUrmnFPa31QCH1ArCHN1YOF8IAL">
<cfset finalText   = replace(dbPassword, "@@12", "+", "all")>
<cfset theKey      = "abcdefgh">
<cfset hashedKey   = hash( theKey, "md5" )>
<cfset padBytes    = left( hashedKey, 16 )>
<cfset keyBytes    = binaryDecode( hashedKey & padBytes , "hex" )>
<cfset finalKey    = binaryEncode( keyBytes, "base64" )>
<cfset decrypted = decrypt( finalText, finalKey, "DESede/ECB/PKCS5Padding", "base64" )>
Decrypted String: <cfdump var="#decrypted#">

推薦答案

看起來你的 c# 函數中需要處理一些額外的曲折以實現兼容性:

Looks like there a few extra twists in your c# function you need to handle to achieve compatibility:

1. .NET 函數修改加密字符串.你需要反轉這些更改，以便解密將其識別為有效的 base64:

1. The .NET function modifies the encrypted string. You need to reverse those changes so decrypt will recognize it as valid base64:

<!--- reverse replacements in encrypted text ie #DB.Password# --->
<cfset dbPassword = "uAugP@@12aP4GGBOLCLRqxlNPL1PSHfTNEZ">
<cfset finalText = replace(dbPassword, "@@12", "+", "all")>

<!--- hash and pad the key (ie "blahblah"), then convert to base64 for CF --->
<cfset theKeyInBase64 = "rpaSPvIvVLlrcmtzPU9/c67Gkj7yL1S5">
<cfset hashedKey   = hash( theKeyInBase64, "md5" )>
<cfset padBytes    = left( hashedKey, 16 )>
<cfset keyBytes    = binaryDecode( hashedKey & padBytes , "hex" )>
<cfset finalKey    = binaryEncode( keyBytes, "base64" )>

<!--- .net code uses the less secure ECB mode --->
<cfset decrypted = decrypt( finalText, finalKey, "DESede/ECB/PKCS5Padding", "base64" )>
Decrypted String: <cfdump var="#decrypted#">

// .NET Code
String text = "some text to encrypt";
String key = "abcdefgh";
String encrypted = EncryptTripleDES(text, key);
// result: encrypted=Hx41SYUrmnFPa31QCH1ArCHN1YOF8IAL
Console.WriteLine("encrypted={0}", encrypted);

<!--- same code, only the encrypted text and key changed ---> 
<cfset dbPassword  = "Hx41SYUrmnFPa31QCH1ArCHN1YOF8IAL">
<cfset finalText   = replace(dbPassword, "@@12", "+", "all")>
<cfset theKey      = "abcdefgh">
<cfset hashedKey   = hash( theKey, "md5" )>
....