Added constants and key factory for key derivation

Author: DJayalath

src/main/java/CryptoResource.java

@@ -1,32 +1,35 @@
 import javax.crypto.Cipher;
 import javax.crypto.NoSuchPaddingException;
+import javax.crypto.SecretKeyFactory;
 import javax.crypto.spec.IvParameterSpec;
 import java.security.NoSuchAlgorithmException;
 
 /* Class that manages setting up cryptographic resources */
 public abstract class CryptoResource {
 
     protected static final int INIT_VECTOR_SIZE = 16;
+    protected static final int SALT_SIZE = 8;
+    protected static final int ITERATION_COUNT = 65536;
+    protected static final int KEY_LENGTH = 256;
+
     private static final String CIPHER_TRANSFORMATION = "AES/CBC/PKCS5PADDING";
+    private static final String KEY_FACTORY_ALGORITHM = "PBKDF2WithHmacSHA256";
+    protected static final String KEY_SPEC_ALGORITHM = "AES";
+    protected static final String RANDOM_SECURE_ALGORITHM = "SHA1PRNG";
+
     protected final Cipher cipher;
+    protected final SecretKeyFactory secretKeyFactory;
 
     /* Initialises cryptographic resources */
     public CryptoResource() throws CryptoException {
         try {
             cipher = Cipher.getInstance(CIPHER_TRANSFORMATION);
+            secretKeyFactory = SecretKeyFactory.getInstance(KEY_FACTORY_ALGORITHM);
         } catch (NoSuchAlgorithmException e) {
             throw new CryptoException("Algorithm not found for " + CIPHER_TRANSFORMATION);
         } catch (NoSuchPaddingException e) {
             throw new CryptoException("Padding scheme not found for " + CIPHER_TRANSFORMATION);
         }
     }
 
-    /* Pads a password to 16 bytes with spaces */
-    protected String padPasswordTo16Bytes(String password) {
-        StringBuilder keyBuilder = new StringBuilder(password);
-        while (keyBuilder.length() < 16)
-            keyBuilder.append(" ");
-        return keyBuilder.toString();
-    }
-
 }