How to perform MAC (Message Authenticate Code) with hashing in .Net CF

Gaurav Sharma

I need to perform MACing using the MD5 algorithm under the .Net Compact framework. I have got code in .Net for desktop version of application but that code is not working in .Net CF.

HMACMD5 myhmacMD5 = new HMACMD5(key);

HMACMD5 API is not working in .Net compact framwork. Is there any alternative way to perform the MACing in the .Net CF.

3 Replies

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Sompal Arya11y ago
Did u get solution,if yes Please tell me I have same problem
Gaurav Sharma15y ago
I need to compute the MAC (Message Authentication Code) using the triple DES for protection of data. The .Net CF does not support the "MACTripleDES" API provided in the .Net Desktop version 3.5. MACTripleDES API is part of System.Security.Cryptography namespace and available in the mscorlib.dll. To solve the problem, i have replaced the mscorlib.dll in .Net CF and used mscorlib.dll from .Net 3.5 version in the project workspace and my code was compiled successfully. But i have got an error during running the application on windows emulator "Could not load type 'System.Security.Cryptography.MACTripleDES' from assembly mscorlib, version =3.5.0.0"
Sahil Jani15y ago
class Class1
  {
    static void Main(string[] args)
    {
      string dataToHash = "this is a test";
      string key = "ABCDEFGHIJKLMNOPQRSTUVWX";

      byte[] dataToHash_Bytes = System.Text.Encoding.Unicode.GetBytes( dataToHash );
      byte[] key_Bytes = System.Text.Encoding.ASCII.GetBytes( key );

      MACTripleDES mac = new MACTripleDES( key_Bytes );

      byte[] result_Bytes = mac.ComputeHash( dataToHash_Bytes );
      Console.WriteLine( System.Text.Encoding.ASCII.GetString( result_Bytes ));

      MD5CryptoServiceProvider md5 = new MD5CryptoServiceProvider();
      byte[] md5_Bytes = md5.ComputeHash( dataToHash_Bytes);
      Console.WriteLine( System.Text.Encoding.ASCII.GetString( md5_Bytes ) );
    }
  }

You can use this one. For this you have to import System.Security.Cryptography.

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