feat: added aes utility class

oxUtil/src/main/java/org/gluu/util/security/AESUtil.java

@@ -0,0 +1,89 @@
+package org.gluu.util.security;
+
+import javax.crypto.*;
+import javax.crypto.spec.GCMParameterSpec;
+import javax.crypto.spec.IvParameterSpec;
+import javax.crypto.spec.PBEKeySpec;
+import javax.crypto.spec.SecretKeySpec;
+import java.security.InvalidAlgorithmParameterException;
+import java.security.InvalidKeyException;
+import java.security.NoSuchAlgorithmException;
+import java.security.SecureRandom;
+import java.security.spec.AlgorithmParameterSpec;
+import java.security.spec.InvalidKeySpecException;
+import java.security.spec.KeySpec;
+import java.util.Base64;
+
+public class AESUtil {
+
+    public static final int IV_LENGTH = 16;
+    public static final int GCM_TAG_LENGTH = 16;
+
+    public static SecretKey generateKey(int n) throws NoSuchAlgorithmException {
+        KeyGenerator keyGenerator = KeyGenerator.getInstance("AES");
+        keyGenerator.init(n);
+        return keyGenerator.generateKey();
+    }
+
+    public static SecretKey getKeyFromPassword(String password, String salt)
+            throws NoSuchAlgorithmException, InvalidKeySpecException {
+        SecretKeyFactory factory = SecretKeyFactory.getInstance("PBKDF2WithHmacSHA256");
+        KeySpec spec = new PBEKeySpec(password.toCharArray(), salt.getBytes(), 65536, 256);
+        return new SecretKeySpec(factory.generateSecret(spec).getEncoded(), "AES");
+    }
+
+    public static IvParameterSpec generateIv() {
+        return generateIv(IV_LENGTH);
+    }
+
+    public static IvParameterSpec generateIv(int size) {
+        byte[] iv = new byte[size];
+        new SecureRandom().nextBytes(iv);
+        return new IvParameterSpec(iv);
+    }
+
+    public static GCMParameterSpec generateGcmSpec() {
+        return new GCMParameterSpec(GCM_TAG_LENGTH * 8, generateIv().getIV());
+    }
+
+
+    public static String encrypt(String algorithm, String input, SecretKey key, AlgorithmParameterSpec spec) throws NoSuchPaddingException, NoSuchAlgorithmException,
+            InvalidAlgorithmParameterException, InvalidKeyException, BadPaddingException, IllegalBlockSizeException {
+
+        Cipher cipher = Cipher.getInstance(algorithm);
+        cipher.init(Cipher.ENCRYPT_MODE, key, spec);
+        byte[] cipherText = cipher.doFinal(input.getBytes());
+        return Base64.getEncoder().encodeToString(cipherText);
+    }
+
+    public static String decrypt(String algorithm, String cipherText, SecretKey key, AlgorithmParameterSpec spec) throws NoSuchPaddingException, NoSuchAlgorithmException,
+            InvalidAlgorithmParameterException, InvalidKeyException, BadPaddingException, IllegalBlockSizeException {
+        Cipher cipher = Cipher.getInstance(algorithm);
+        cipher.init(Cipher.DECRYPT_MODE, key, spec);
+        byte[] plainText = cipher.doFinal(Base64.getDecoder().decode(cipherText));
+        return new String(plainText);
+    }
+
+    /*
+     public static void main(String[] args) throws NoSuchPaddingException, InvalidKeyException, NoSuchAlgorithmException, IllegalBlockSizeException, BadPaddingException, InvalidAlgorithmParameterException {
+     String input = "textToEncrypt";
+     SecretKey key = AESUtil.generateKey(128);
+     IvParameterSpec ivParameterSpec = AESUtil.generateIv();
+
+     // CBC
+     String algorithm = "AES/CBC/PKCS5Padding";
+     String cipherText = AESUtil.encrypt(algorithm, input, key, ivParameterSpec);
+     String plainText = AESUtil.decrypt(algorithm, cipherText, key, ivParameterSpec);
+     boolean equals = input.equals(plainText);
+     System.out.println(equals);
+
+     // GCM
+     algorithm = "AES/GCM/NoPadding";
+     final GCMParameterSpec gcmSpec = generateGcmSpec();
+     cipherText = AESUtil.encrypt(algorithm, input, key, gcmSpec);
+     plainText = AESUtil.decrypt(algorithm, cipherText, key, gcmSpec);
+     equals = input.equals(plainText);
+     System.out.println(equals);
+     }
+     */
+}