Java/Security/MAC

Generating a Message Authentication Code (MAC)

   <source lang="java">

import javax.crypto.KeyGenerator; import javax.crypto.Mac; import javax.crypto.SecretKey; public class Main {

 public static void main(String[] argv) throws Exception {
   KeyGenerator keyGen = KeyGenerator.getInstance("HmacMD5");
   SecretKey key = keyGen.generateKey();
   Mac mac = Mac.getInstance(key.getAlgorithm());
   mac.init(key);
   String str = "This message will be digested";
   byte[] utf8 = str.getBytes("UTF8");
   byte[] digest = mac.doFinal(utf8);
   String digestB64 = new sun.misc.BASE64Encoder().encode(digest);
   System.out.println(digestB64);
 }

}

 </source>
   
  
 
  

Generating a Message Authentication Code (MAC) Key

   <source lang="java">

import javax.crypto.KeyGenerator; import javax.crypto.SecretKey; public class Main {

 public static void main(String[] argv) throws Exception {
   KeyGenerator keyGen = KeyGenerator.getInstance("HmacMD5");
   SecretKey key = keyGen.generateKey();
   // Generate a key for the HMAC-SHA1 keyed-hashing algorithm
   keyGen = KeyGenerator.getInstance("HmacSHA1");
   key = keyGen.generateKey();
 }

}

 </source>