SecretKeyFactory.getInstance（“PBKDF2WithHmacSHA512”）抛出NoSuchAlgorithmException

Question

After a little bit of research and some work I finally was able to hash salt the password now there is a question which is on my mind I have used the SHA1 method and I would like to try to use the SHA512 because I was told it's better (more secure) so the following is my code its a little bit all over the place but I think its comprehensible so:

public class Safety
{
   //calling some parameters for possible later changes
   public static final String algorithm = "PBKDF2WithHmacSHA1";
   public static final int saltbytesize = 24;
   public static final int hashbytesize = 24;
   public static final int iterations = 1000;
   public static final int iIndex = 0;
   public static final int sIndex = 1;
   public static final int pbkIndex = 2;

   public static Users passwordHash(Users user) throws NoSuchAlgorithmException,
                                                       InvalidKeySpecException
   {
      SecureRandom sR = new SecureRandom();

      byte[] pws = new byte[saltbytesize];

      sR.nextBytes(pws);
      byte[] pwh = pbkdf2(user.getPassword().toCharArray(), pws, iterations, hashbytesize);

      user.setPassword(toHex(pwh));

      byte[] sas = new byte[saltbytesize];

      sR.nextBytes(sas);

      byte[] sah = pbkdf2(user.getsA().toCharArray(), sas, iterations, hashbytesize);

      user.setsA(toHex(sah));

      user.setUserhash(pws);

      user.setSahash(sas);

      return user;
   }

   public static boolean hashpassword(String username, String password, Users user)
   throws NoSuchAlgorithmException,
          InvalidKeySpecException
   {
      byte[] pws = user.getUserhash();

      byte[] pwh = pbkdf2(password.toCharArray(), pws, iterations, hashbytesize);

      String searcher = toHex(pwh) + username;

      String searched = user.getPassword() + user.getUsername();

      if (searcher.equals(searched))
      {
         return true;
      }
      return false;
   }

   private static byte[] pbkdf2(char[] password, byte[] salt,
                                int iterations, int bytes)
      throws NoSuchAlgorithmException, InvalidKeySpecException
   {
      PBEKeySpec spec = new PBEKeySpec(password, salt, iterations, bytes * 8);
      SecretKeyFactory skf = SecretKeyFactory.getInstance(algorithm);
      return skf.generateSecret(spec).getEncoded();
   }

   private static String toHex(byte[] array)
   {
      BigInteger bi = new BigInteger(1, array);

      String hex = bi.toString(16);

      int paddingLength = (array.length * 2) - hex.length();

      if (paddingLength > 0)
         return String.format("%0" + paddingLength + "d", 0) + hex;
      else
         return hex;
   }
}

So that's my code, however, I have not been able to make that SHA512 and I have already tried public static final String algorithm = "PBKDF2WithHmacSHA512" but that doesn't seem to be the right string for the algorithm since it throws the no such algorithm exception.

I also welcome any changes that would make the code better.

as stated above! relevant few line(s) of code

public static final String algorithm = "PBKDF2WithHmacSHA512"<<<<<

Answer 1

That is not possible out of the box

The OpenJDK implementation does only provide a PBKDF2HmacSHA1Factory.java which has the "HmacSHA1" digest harcoded. As far as I tested, the Oracle JDK is not different in that sense.

What you have to do is derive the PBKDF2HmacSHA1Factory (come on, it is open !) and add a parameter to its constructor. You may avoid the mess of creating your own Provider , and just initialize and use your factory as follows:

PBKDF_SecretKeyFactory kf = new PBKDF_SecretKeyFactory("HmacSHA512");
KeySpec ks = new PBEKeySpec(password,salt,iterations,bitlen);
byte key[] = kf.engineGenerateSecret(ks).getEncoded();