package org.jastacry.layer;
   
   import java.nio.charset.StandardCharsets;
   import java.security.MessageDigest;
   import java.security.NoSuchAlgorithmException;
   import java.util.Arrays;
   
   import javax.crypto.spec.SecretKeySpec;
   
  import org.jastacry.JastacryException;
  
  /**
   * MD5 DES Layer class.
   *
   * <p>SPDX-License-Identifier: MIT
   *
   * @author Kai Kretschmann
   */
  public class Md5DesLayer extends AbstractCipherLayer
  {
      /**
       * static name of the layer.
       */
      public static final String LAYERNAME = "MD5DES Layer";
  
      /**
       * Used algorithm name.
       */
      private static final String MYALG = "DESede/CBC/PKCS5Padding";
  
      /**
       * Used algorithm name for the key.
       */
      private static final String MYKEYALG = "DESede";
  
      /**
       * Used algorithm name for the hash.
       */
      private static final String MYHASHALG = "md5";
  
      /**
       * IV length.
       */
      private static final int IVLEN = 8;
  
      /**
       * Salt length.
       */
      private static final int SALTLEN = 8;
  
      /**
       * Iteration count.
       */
      private static final int COUNT = 20;
  
      /**
       * Size of key.
       */
      private static final int KEYSIZE = 24;
  
      /**
       * local key storage implementation.
       */
      private byte[] keyBytes; // NOPMD by kkretsch on 29.03.18 14:53
  
      /**
       * Constructor of Md5DesLayer.
       */
      public Md5DesLayer()
      {
          super(Md5DesLayer.class, LAYERNAME);
      }
  
      /**
       * Generate Keys from plain password.
       *
       * @throws JastacryException on error
       */
      @Override
      protected final void setupPbe() throws JastacryException
      {
          logger.debug("in child setupPBE");
          pbeKey = new SecretKeySpec(keyBytes, MYKEYALG);
          pbeSecretKeySpec = new SecretKeySpec(pbeKey.getEncoded(), strKeyAlg);
      }
  
      /**
       * init function.
       *
       * @param data to initialize the crypt value.
       */
      @Override
      public final void init(final String data)
      {
          super.init();
  
          this.chPasswd = data.toCharArray();
          try
          {
             final MessageDigest msgDigest = MessageDigest.getInstance(MYHASHALG);
             final byte[] digestOfPassword = msgDigest.digest(data.getBytes(StandardCharsets.UTF_8));
             keyBytes = Arrays.copyOf(digestOfPassword, KEYSIZE);
         }
         catch (final NoSuchAlgorithmException e)
         {
             logger.catching(e);
         }
     }
 
     @Override
     protected final String getMyAlg()
     {
         return MYALG;
     }
 
     @Override
     protected final String getMyKeyAlg()
     {
         return MYKEYALG;
     }
 
     @Override
     protected int getMySaltLen()
     {
         return SALTLEN;
     }
 
     @Override
     protected int getMyIvLen()
     {
         return IVLEN;
     }
 
     @Override
     protected int getMyCount()
     {
         return COUNT;
     }
 
     @Override
     protected int getMyKeysize()
     {
         return KEYSIZE;
     }
 
     /**
      * Override equals method from object class.
      * @param o object to compare with
      * @return true or false
      */
     @Override
     public boolean equals(final Object o)
     {
         if (o == this)
         {
             return true;
         }
         if (!(o instanceof Md5DesLayer))
         {
             return false;
         }
 
         final Md5DesLayer./../org/jastacry/layer/Md5DesLayer.html#Md5DesLayer">Md5DesLayer layer = (Md5DesLayer) o;
         return Arrays.equals(layer.keyBytes, this.keyBytes);
     }
 
     /**
      * Override equals method from object class.
      * @return hash of properties
      */
     @Override
     public int hashCode()
     {
         return Arrays.hashCode(keyBytes);
     }
 }